General Neurology
Brain death/death by neurologic criteria
Nov. 09, 2024
Worddefinition
At vero eos et accusamus et iusto odio dignissimos ducimus qui blanditiis praesentium voluptatum deleniti atque corrupti quos dolores et quas.
Micturition syncope and defecation syncope …
- Updated 05.14.2024
- Released 01.27.2004
- Expires For CME 05.14.2027
Micturition syncope and defecation syncope
Introduction
Overview
The author explains the clinical presentation, pathophysiology, diagnostic work-up, and management of micturition and defecation syncopes. Micturition syncope is a fairly common disorder that generally occurs in men. Younger men with micturition syncope typically have a benign self-limited condition, whereas older male patients and female patients of any age typically have significant medical comorbidities and orthostatic hypotension. In contrast, defecation syncope is a relatively rare disorder that typically occurs in middle-aged or older individuals and affects women more often than men. More than one third of patients with defecation syncope die within 2 years of complications of their underlying diseases. Alcohol intake is an important precipitating factor for micturition syncope in younger patients (less than 55 years of age), but it is rarely a factor associated with defecation syncope.
Key points
|
• Micturition syncope is a fairly common disorder that generally occurs in men. | |
|
• Younger men with micturition syncope typically have a benign self-limited condition, whereas older male patients and female patients of any age typically have significant medical comorbidities and orthostatic hypotension. | |
|
• Particularly among older patients (over 55 years of age), micturition syncope typically occurs only when patients void immediately after arising from the supine position after prolonged recumbency. Thus, micturition syncope is most common in the evening or early morning, especially in older patients (over 55 years of age). | |
|
• Micturition syncope in younger patients (less than 55 years of age) tends to occur in the evening or nighttime before midnight, whereas in older patients, it tends to occur after midnight or early in the morning. | |
|
• Micturition syncope most often occurs at the termination of or just after urination. | |
|
• Defecation syncope is a relatively rare disorder that occurs typically in middle-aged or older individuals and affects women more often than men. | |
|
• More than one third of patients with defecation syncope die within 2 years of complications of their underlying diseases. |
Historical note and terminology
Micturition syncope was first described by Rugg-Gunn in 1946 (71) and Proudfit and Forteza in 1959. Micturition syncope is defined as syncope occurring during or immediately after urination.
Defecation syncope was first described by Pathy in 1978 and later studied in detail by Kapoor and colleagues (39). Defecation syncope is defined as syncope occurring during or immediately after defecation.
Defecation and micturition syncopes are forms of the so-called situational syncopes, which occur immediately after precipitating situations, such as urination, defecation, cough, swallowing, or rarely laughing (08; 22). Generally, such situational syncopes are considered forms of neurally mediated syncope with reflex-mediated vasodilation and bradycardia (08; 24), but other mechanisms can also be involved.
Clinical manifestations
Presentation and course
|
• Micturition syncope is a fairly common condition that occurs typically in men over a wide age span but can occur uncommonly in older women and rarely in children, particularly boys. | |
|
• Particularly among older patients (over 55 years of age), micturition syncope typically occurs only when patients void immediately after arising from the supine position after prolonged recumbency. | |
|
• Micturition syncope is most common in the evening or early morning. | |
|
• The circadian pattern of micturition syncope varies by age: in younger patients (less than 55 years of age), it tends to occur in the evening or nighttime before midnight, whereas in older patients, it tends to occur after midnight or early in the morning. | |
|
• Micturition syncope most often occurs at the termination of or just after urination. | |
|
• Defecation syncope is a relatively rare disorder that occurs typically in middle-aged or older individuals and affects women somewhat more often than men. | |
|
• Unlike micturition syncope, there is no strong diurnal variation with defecation syncope. | |
|
• With micturition and defecation syncopes, there may be associated brief jerking or rhythmic movements (ie, convulsive syncope), but there is no associated incontinence, tongue biting, or postictal state. Recovery usually occurs within seconds without vasomotor or other sequelae. Patients are amnestic for the period of lost consciousness. |
Micturition syncope is a fairly common disorder that occurs typically in men over a wide age span but can occur uncommonly in older women and rarely in children, particularly boys (41; 59; 04; 01; 50; 87). Micturition syncope represents perhaps 2% to 8% of cases of syncope, with more common causes being orthostatic hypotension and vasovagal syncope (49; 73; 34; 51).
Attacks in males may begin in the teenage years, and cases have rarely been reported as young as age 7 and 9 (50; 87). Particularly among older patients (over 55 years of age), micturition syncope typically occurs only when patients void immediately after arising from the supine position after prolonged recumbency (66; 83; 41). Thus, micturition syncope is most common in the evening or early morning (47; 73; 41; 81), especially in older patients (over 55 years of age). The circadian pattern of micturition syncope varies by age: in younger patients (less than 55 years of age), it tends to occur in the evening or nighttime before midnight, whereas in older patients, it tends to occur after midnight or early in the morning (83). Micturition syncope most often occurs at the termination of or just after urination (47; 73). A form of micturition syncope can also occur with intermittent catheterization, eg, in tetraplegic subjects (65; 84).
Although rare, paragangliomas of the urinary bladder warrant special mention, as they need to be considered when evaluating hypertensive patients with headache, palpitations, or syncope related to micturition (84; 33; 86; 02; 90; 32; 93) (see Clinical vignette case 2). These are tumors of chromaffin tissue originating from the sympathetic innervations of the urinary bladder, and as such they may secrete catecholamines and give rise to a clinical presentation like that of a hyperfunctioning adrenal pheochromocytoma. They are typically recognized by their characteristic presentation of hypertensive crisis and postmicturition syncope (69; 68; 84; 33; 86; 02; 90; 32; 93). Patients may present with episodes of headache, palpitations, hot flushes, sweating, and poorly controlled hypertension; such manifestations of hypertensive crises are at times associated with micturition or micturition syncope (occurring, though, typically at the end or shortly after micturition, accompanied by postmicturition hypotension) (68; 84). An additional symptom may be painless hematuria, which may be the presenting complaint (68).
Defecation syncope is a relatively rare disorder that occurs typically in middle-aged or older individuals and affects women somewhat more often than men (61; 39; 41; 59; 04). In general, the age distribution is older for patients with defecation syncope than those with micturition syncope (41; 04). About half of the patients with defecation syncope experience multiple episodes (39). Most patients are recumbent (either asleep or at bed rest) before getting up to have a bowel movement. Gastrointestinal symptoms before syncope can include a strong urge to defecate, abdominal cramps and bloating, nausea and vomiting, diarrhea, and constipation (39; 83). Unlike micturition syncope, there is no strong diurnal variation with defecation syncope (41).
With micturition and defecation syncopes, there may be associated brief jerking or rhythmic movements (ie, convulsive syncope), but there is no associated incontinence, tongue biting, or postictal state. Recovery usually occurs within seconds without vasomotor or other sequelae. Patients are amnestic for the period of lost consciousness. The clinical manifestations of syncope per se are described in the general chapter on Syncope.
Prognosis and complications
The long-term prognosis of syncope depends largely on the prognosis of the underlying condition, but syncope itself can result in severe bodily injury. In general, patients with micturition or defecation syndrome, like other situational syncopes, are typically older, more often male, have a higher prevalence of hypertension, seldom have prodromes, and experience more injuries at the time of syncope (91).
Younger men with micturition syncope typically have a benign self-limited condition, caused by a transient disturbance of normal physiologic functions (eg, from overindulgence in food and alcohol with inadequate sleep), but do not typically have significant underlying morbidity (66; 58; 80; 74; 23). In contrast, older male patients and female patients of any age with micturition syncope typically have significant medical comorbidities and a majority have orthostatic hypotension (38). Many patients have recurrent episodes (73).
Defecation syncope is not a “benign” isolated physiologic event (39), although it is sometimes dismissed as a benign neurally mediated syncope (22). Half of the patients with defecation syncope have recurrent syncope within 2 years, but most recurrences are not associated with defecation (39). Bilateral subcortical border-zone infarction has been reported following episodes of prolonged defecation syncope (82). More than one third of patients with defecation syncope die within 2 years of complications of their underlying diseases (39).
Clinical vignette
Case 1. Catheterization-associated micturition syncope in a tetraplegic patient (65). A 47-year-old man with C7 tetraplegia developed occasional syncope several minutes after intermittent catheterizations in the sitting position associated with hypotension and bradycardia. Catheterization-associated syncope resolved on withdrawal of fluoxetine, which had been used for situational depression. However, some degree of catheterization-associated hypotension without syncope persisted. Subsequently, catheterization-associated hypotension resolved with management of bladder hyperreflexia with botulinum-A toxin injections into the detrusor. Important clinical lessons emphasized by this case include the following: (1) overdistention of the bladder should be avoided; (2) bladder volume should be gradually decreased, particularly if the bladder is overdistended; (3) bladder hyperreflexia should be carefully controlled in patients with cervical or thoracic myelopathy; and (4) medications with hypotensive side effects may contribute additively or synergistically with episodic hypotensive factors (eg, micturition) to collectively cause syncope.
Case 2. Micturition syncope and hypertensive crises due to a bladder paraganglioma (90). A 43-year-old man was admitted with a several-week history of frequent micturition syncope concomitant with hypertensive crises. Physical examination was normal.
Urine red blood cells were marginally elevated at 5.5/HPF (normal range ≤3/ HPF). Serum biomarkers included the following: normetanephrine 18,064 pmol/L (normal range ≤710 pmol/L), metanephrine 195 pmol/L (normal range ≤421 pmol/L), norepinephrine 8,591 pmol/L (normal range 414–4,434 pmol/L), epinephrine 152 pmol/L (normal range ≤606 pmol/L). Urine biomarkers included the following: normetanephrine in 24-hour urine 5,630 nmol/24 hours (normal range < 312 nmol/24 hours) and metanephrine in 24-hour urine 79 nmol/24 hours (normal range < 216 nmol/24 hours).
A computed tomography urography scan identified a bladder tumor (4.8 cm × 3.7 cm) in the right anterior wall of the bladder with heterogeneous enhancement in the arterial phase and decreased enhancement of venous phase and excretory phase. MRI also identified a bladder tumor with high signal intensity on T2-weighted imaging (4.9 cm × 3.8 cm) in the right anterior wall of the bladder.
Cystoscopy revealed a cauliflower-shaped mass with the right anterior wall of the bladder bulging inward and a tip in the right wall, approximately 0.8 cm in diameter.
-
Pedunculated, cauliflower-like mass in right lateral wall of the bladder
Cystoscopy shows a pedunculated, cauliflower-like mass in the right lateral wall of the bladder with a diameter of about 0.8cm. (Source: Wang Z, Liu F, Li C, et al. Case report: octreotide plus CVD chemotherapy for the treatmen...
The preoperative diagnosis was suspected bladder paraganglioma concomitant with bladder tumor.
The patient received preoperative phenoxybenzamine with aggressive volume repletion. He then underwent laparoscopic partial cystectomy combined with transurethral resection of the bladder tumor.
Postoperative pathology confirmed a bladder paraganglioma (T2N0M0, Stage II) concomitant with urothelial papilloma, a rare benign neoplasm composed of a delicate fibrovascular core covered by normal urothelium.
Immunohistochemistry of the bladder paraganglioma was positive for Ki-67 (15%), chromogranin A (CgA), succinate dehydrogenase B (SDHB), somatostatin receptor 2 (SSTR2), and synapsin (Syn) and negative for S-100 (a tumor marker that can be found in paraganglioma stromal cells).
Immunohistochemistry of the urothelial papilloma was positive for CK20 (umbrella cells) and Ki-67 (1%).
-
Staining of the urothelial papilloma with H&E and immunohistochemical staining for CK20 (umbrella cells)
(Source: Wang Z, Liu F, Li C, et al. Case report: octreotide plus CVD chemotherapy for the treatment of multiple metastatic paragangliomas after double resection for functional bladder paraganglioma and urothelial papilloma. Fr...
-
Immunohistochemical staining of the urothelial papilloma with Ki-67 (1%)
(Source: Wang Z, Liu F, Li C, et al. Case report: octreotide plus CVD chemotherapy for the treatment of multiple metastatic paragangliomas after double resection for functional bladder paraganglioma and urothelial papilloma. Fr...
The final diagnosis was intermediate-risk functional bladder paraganglioma concomitant with urothelial papilloma. After recovery, he had normal urination without syncope.
Eight months after his surgery, he was examined because of a skull mass. 18F-FDG positron emission tomography (PET)/CT identified widespread metastases with multiple high-uptake lesions in the liver (2.8 cm × 2.4 cm), bilateral pulmonary nodules (maximum diameter 5 mm), and high-uptake masses and osteolytic bone destruction in the right parietal skull bone, vertebral body, and ilium.
-
Metastatic paraganglioma PET/CT results show high-uptake lesions in liver (1)
18F-FDG PET/CT for metastatic paraganglioma, showing multiple high-uptake lesions in the liver. Transverse image. (Source: Wang Z, Liu F, Li C, et al. Case report: octreotide plus CVD chemotherapy for the treatment of multiple ...
-
Metastatic paraganglioma PET/CT results show high-uptake lesions in liver (2)
18F-FDG PET/CT for metastatic paraganglioma, showing multiple high-uptake lesions in the liver. Frontal image. (Source: Wang Z, Liu F, Li C, et al. Case report: octreotide plus CVD chemotherapy for the treatment of multiple met...
-
Metastatic paraganglioma PET/CT results show high-uptake lesions with osteolytic bone destruction of right parietal skull bone
18F-FDG PET/CT for metastatic paraganglioma, showing high-uptake lesions with osteolytic bone destruction of the right parietal skull bone (arrows). Transverse image. (Source: Wang Z, Liu F, Li C, et al. Case report: octreotide...
-
Metastatic paraganglioma PET/CT results show high-uptake lesions with osteolytic bone destruction of vertebral body and ilium
18F-FDG PET/CT for metastatic paraganglioma, showing high-uptake lesions with osteolytic bone destruction of a vertebral body and the ilium (arrows). Transverse image. (Source: Wang Z, Liu F, Li C, et al. Case report: octreotid...
Because of positive expression of SSTR2 with the original pathology, the patient underwent 18F-DOTATATE PET/CT targeted imaging. This showed multiple high-uptake nodules in the liver and lungs, and high-uptake masses with osteolytic bone destruction of the right parietal skull and iliac bones.
-
Metastatic paraganglioma PET/CT results show high-uptake localizations in the liver (1)
Results of 18F-DOTATATE PET/CT for metastatic paraganglioma, showing multiple high-uptake localizations in the liver. (Source: Wang Z, Liu F, Li C, et al. Case report: octreotide plus CVD chemotherapy for the treatment of multi...
-
Metastatic paraganglioma PET/CT results show high-uptake localizations in the liver (2)
Results of 18F-DOTATATE PET/CT for metastatic paragangliomas, showing multiple high-uptake localizations in the liver. (Source: Wang Z, Liu F, Li C, et al. Case report: octreotide plus CVD chemotherapy for the treatment of mult...
-
Metastatic paraganglioma PET/CT results show high-uptake localizations in the lung
Results of 18F-DOTATATE PET/CT for metastatic paraganglioma, showing multiple high-uptake localizations in the lung. (Source: Wang Z, Liu F, Li C, et al. Case report: octreotide plus CVD chemotherapy for the treatment of multip...
-
Metastatic paraganglioma PET/CT results show high-uptake localizations with osteolytic bone destruction of right parietal skull bone
Results of 18F-DOTATATE PET/CT for metastatic paraganglioma, showing high-uptake localizations with osteolytic bone destruction of right parietal skull bone. (Source: Wang Z, Liu F, Li C, et al. Case report: octreotide plus CVD...
-
Metastatic paraganglioma PET/CT results show high-uptake localizations with osteolytic bone destruction of the ilium
Results of 18F-DOTATATE PET/CT for metastatic paraganglioma, showing high-uptake localizations with osteolytic bone destruction of the ilium. (Source: Wang Z, Liu F, Li C, et al. Case report: octreotide plus CVD chemotherapy fo...
The patient received six courses of CVD chemotherapy [cyclophosphamide (1.4 g day 1), vincristine (2 mg day 1), and dacarbazine (0.4 g days 1 through 5)] every 16 to 26 days, plus octreotide LAR (30 mg intramuscularly every 4 weeks).
Micturition syncope and hypertensive crises: diagnosis and treatment flowchart
(Source: Wang Z, Liu F, Li C, et al. Case report: octreotide plus CVD chemotherapy for the treatment of multiple metastatic paragangliomas after double resection for functional bladder paraganglioma and urothelial papilloma. Fr...
After finishing the sixth course of CVD chemotherapy, he continued octreotide therapy (30 mg intramuscularly every 3 months) to control his hormonally functional paraganglioma.
CT scans showed no significant progression in the size of the lung, liver, skull, and ilium metastases. Nevertheless, the levels of vanillylmandelic acid in 24-hour urine samples slowly declined, from 24.80 mg/24 hours (normal range ≤12.00 mg/24 hours), ultimately achieving a level of 17.10 mg/24 hours after 6 months.
-
No significant progression of lung metastases size after chemotherapy
The size of metastases in the lung did not significantly change with two courses (far left), four courses (left center), and six courses of chemotherapy (right center), and 6-month follow-up (far right). (Source: Wang Z, Liu F,...
-
No significant progression of liver metastases size after chemotherapy
The size of metastases in the liver did not significantly change with two courses (far left), four courses (left center), and six courses of chemotherapy (right center), and 6-month follow-up (far right). (Source: Wang Z, Liu F...
-
No significant progression of skull metastases size after chemotherapy
The size of metastases in the skull did not significantly change with two courses (far left), four courses (left center), and six courses of chemotherapy (right center), and 6-month follow-up (far right). (Source: Wang Z, Liu F...
-
No significant progression of ilium metastases size after chemotherapy
The size of metastases in the ilium did not significantly change with two courses (far left), four courses (left center), and six courses of chemotherapy (right center), and 6-month follow-up (far right). (Source: Wang Z, Liu F...
Biological basis
Pathophysiology
Several pathophysiologic processes may cause or contribute to micturition- or defecation-related syncopes:
|
• Valsalva-induced decreased cardiac output |
Several factors have been proposed to increase the likelihood that micturition will produce syncope:
|
• upright and motionless (26) | |
|
• orthostatic hypotension (47; 46; 23; 73; 26; 97) | |
|
• excess alcohol ingestion (47; 74; 36) | |
|
• inadequate sleep or marked fatigue (47; 74) | |
|
• rising from bed (66; 47; 46; 11; 26; 77) because of altered vasomotor reflexes during sleep and vasodilation in a warm bed, followed by standing in place with distention of dependent capacitance vessels and lack of operation of the muscle pump mechanism to encourage venous return. This is thought to partly explain the relative excess of micturition syncope among men (11). | |
|
• bladder outlet obstruction (eg, as from prostatic hypertrophy), requiring strain and Valsalva to accomplish voiding (11) | |
|
• recent meal or overeating (58; 73; 26) | |
|
• fasting (47; 74) | |
|
• anxiety or stress (58; 73; 26) | |
|
• high ambient heat or fever (58; 73; 26) | |
|
• recent upper respiratory infection (74), including with SARS-CoV-2 (07) | |
|
• cardiac arrhythmias, including sick sinus syndrome and atrial fibrillation (42; 45) | |
|
• severe carotid artery or intracranial artery stenosis or occlusion | |
|
• pregnancy (77) | |
|
• rare functional paragangliomas of the urinary bladder (15; 05; 95; 84) |
Similarly, several factors have been suggested to increase the likelihood that defecation will produce syncope:
|
• orthostatic hypotension (39; 26; 97) | |
|
• rising from bed (39; 26) because of altered vasomotor reflexes and vasodilation and other factors (see above) | |
|
• cardiac arrhythmias, including sick sinus syndrome (39) | |
|
• end-stage liver disease (60) | |
|
• severe carotid artery or intracranial artery stenosis or occlusion | |
|
• viral syndrome (39) | |
|
• fatigue (39) | |
|
• recent meal or overeating (26) | |
|
• anxiety or stress (26) | |
|
• high ambient heat or fever (26) | |
|
• structural intestinal lesions (eg, Meckel diverticulum, Morgagni hernia, appendicitis, huge uterine fibroids), especially those requiring a severe strain for defecation (39; 92; 85) | |
|
• other pelvic masses (eg, huge uterine fibroids) (85) | |
|
• deep venous thromboses (40; 60) |
Several pathophysiologic processes may cause or contribute to micturition- or defecation-related syncopes:
Valsalva-induced decreased cardiac output. Micturition and defecation result from coordination of both voluntary and reflex activity. The Valsalva maneuver occurs during voluntary straining with the glottis closed, and can be repetitive and intense, causing large swings in arterial blood pressure and heart rate (52; 66; 67; 79). Valsalva during micturition is likely most common in patients with bladder outlet obstruction (18; 46; 34). Valsalva during defecation typically achieves intrathoracic pressures above 40 mm Hg (78; 79). The Valsalva maneuver causes increased intrathoracic pressures, which in turn cause decreased venous return to the atria with resultant decreased stroke volume, decreased blood pressure, and decreased cerebral blood flow. However, in contrast to the situation with cough syncope, it seems unlikely that a person could strain sufficiently during micturition or defecation to produce syncope by Valsalva alone (27). Other factors, such as an exaggerated lordotic posture during voiding, may also interfere with venous return and contribute to micturition syncope (27; 23).
Cardiac arrhythmias. Micturition and defecation can precipitate vagally mediated cardiac arrhythmias, including bradycardia, sinus arrest, and atrioventricular conduction block (52; 74; 39; 79). Similarly digital rectal examination, enemas, and colonoscopy can induce cardiac arrhythmias and syncope (21; 06; 62; 14; 39; 65). Vagal stimulation can also induce ventricular asystole in some patients, particularly if vagal tone has been accentuated by cholinergic agents (eg, acetylcholinesterase inhibitors), hypoxia, hypercapnia, or tracheal suctioning in the setting of respiratory infection (75; 44). In addition, patients with acute coronary syndrome are particularly vulnerable to syncope related to excessive straining during defecation (79); this may partly relate to decreased coronary artery blood flow and arrhythmias during Valsalva (79).
Orthostatic hypotension. Blood pressure falls during sleep without associated changes in heart rate, suggesting altered baroreceptor mechanisms during sleep and on rising (70; 27). Standing to void aggravates this impairment in postural blood pressure control. Preexisting medication-related or other orthostatic hypotension is a significant risk factor for both micturition and defecation syncopes (47; 46; 23; 94; 39; 73; 11; 26; 77).
Loss of pressor effect of distended bladder. Bladder distention is associated with increased muscle nerve sympathetic activity and elevated blood pressure (25; 20; 72). Blocking the afferent innervation of the bladder with instillation of procaine before bladder distention prevents the changes in sympathetic activity and blood pressure associated with bladder filling (20). Sudden decompression of a chronically distended bladder can produce hypotension (55; 76; 48; 27; 65). Loss of the pressor effect of a distended bladder may be more severe in the presence of a urinary tract infection (17) or pregnancy (77) or in tetraplegic patients with autonomic hyperreflexia (65).
Pulmonary embolism. This is one of the most commonly identified causes in patients with defecation-related syncope (40; 60). The act of defecation may facilitate embolization of a venous clot. Syncope has been identified as a common presentation of pulmonary embolism, but it is unclear how often this is precipitated by defecation (03; 64).
Functional inferior vena cava obstruction. Functional inferior vena cava obstruction at the diaphragmatic hiatus during Valsalva has been reported to cause defecation-related syncope, as a result of decreased venous return and secondary decreased cardiac output (10). The functional obstruction and the defecation-related syncope can be relieved with mobilization of the inferior vena cava and crural myotomy (10).
Functional obliteration of the right atrium. Excessive paradoxical elevation of the left hemidiaphragm during Valsalva, following surgical trauma to the left phrenic nerve, has been reported to cause defecation-related syncope, as a result of obliteration of the right atrial cavity and a secondary precipitous drop in cardiac output (89). Although the authors considered this a case of cardiac syncope mimicking defecation syncope, it meets the definition of defecation syncope and should instead be considered a rare cardiac mechanism for defecation syncope.
Cardioinhibitory situational vasovagal syncope. Vasovagal syncope has been postulated as a cause of syncope in some patients with micturition syncope, particularly when micturition syncope occurs in the absence of bladder outlet obstruction or significant straining (13; 46; 16; 37). Several cases of defecation syncope have been reported in which vasovagal syncope was the presumed mechanism of defecation syncope, including a patient diagnosed with splanchnic sympathetic dysfunction (54) and a patient found to have a Morgagni hernia (ie, an uncommon type of diaphragmatic hernia) (92).
Decreased cerebral blood flow. Valsalva during defecation or micturition may further impair cerebral circulation in patients with already compromised cerebral blood flow because of extracranial or intracranial arterial stenosis or occlusion (39). Several factors may act synergistically in such cases, including decreased cardiac output as a result of Valsalva-induced decreased venous return, increased cerebrospinal fluid pressure transmitted from increased intra-abdominal and intrathoracic pressures (28; 29), and secondary hypocapnia causing cerebral arterial vasoconstriction. However, empiric support for this mechanism is weak in patients with micturition or defecation syncopes.
Seizure. Rarely, micturition or defecation, and their associated changes in cerebral blood flow or other pathophysiologic processes, may actually trigger a reflex seizure with resultant loss of consciousness followed by a postictal state (98; 30).
Generalized autonomic dysfunction. Patients with multisystem atrophy may be prone to micturition syncope (88). Such patients have lower baseline blood pressure, small blood pressure and heart rate increases during bladder filling, and an abnormally increased fall in blood pressure for a longer duration after voiding. They may also have increased abdominal straining because of difficulty in voiding, which acts to decrease venous return to the heart.
Alcohol intake. Alcohol intake is an important precipitating factor for micturition syncope in younger patients (less than 55 years of age) (83; 04) but is rarely a factor associated with defecation syncope (41; 04) or with common vasovagal syncope (04).
Catecholamine release. Functional paragangliomas of the urinary bladder are rare tumors that can release catecholamines and precipitate syncope during micturition (15; 05; 95; 33; 86; 90). The term paraganglioma includes all the tumors deriving from the body's paraganglion system, which are categorized as intra-adrenal (pheochromocytoma) and extra-adrenal or paraganglion (56). About 10% of all extra-adrenal paragangliomas involve the bladder and can be functional and nonfunctional (56). Early preoperative diagnosis of functional paragangliomas of the urinary bladder is difficult, but these tumors should be suspected in patients with the typical symptom profile, which can include micturition-induced syncope, often associated with headache, diaphoresis, palpitations, and hematuria (95; 86; 90). A similar situation of catecholamine release and syncope can occur in tetraplegic patients with autonomic dysreflexia during intermittent catheterization (65).
Epidemiology
In a retrospective study of 3140 patients who underwent head-up tilt testing, 354 (11%) were diagnosed with situational syncope (99). Micturition syncope (50.85%) represented only about 51% of situational syncope, whereas defecation syncope represented only about 16% of situational syncope. Patients with syncope triggered by micturition were more likely to be men.
Differential diagnosis
Confusing conditions
Micturition and defecation syncopes may be confused with epilepsy, particularly as the syncopal attacks may be associated with secondary arrhythmic convulsive jerks of the extremities (ie, convulsive syncope) (31; 19). However, there is no associated aura, postictal confusion, tongue biting, or incontinence. Furthermore, the syncope improves or resolves without recourse to anticonvulsants. Rare patients with micturition- or cough-associated syncope may have interictal epileptiform activity on electroencephalograms, postictal symptoms, and apparent control of syncope with anticonvulsants, and in such rare cases, micturition- or defecation-triggered changes in cerebral blood flow or other factors may actually trigger a seizure (30).
Diagnostic workup
|
• The diagnostic work-up varies by the clinical circumstances and the clinically suspected etiologies of micturition or defecation syncope. | |
|
• Lung function, cardiac function, orthostatic pulse and blood pressure, and blood volume should be assessed clinically. | |
|
• An electrocardiogram should be obtained. | |
|
• If the history and examination do not suggest an underlying significant comorbidity in a man with micturition syncope, particularly a man younger than 50 years of age, further diagnostic studies are usually unrevealing. | |
|
• In an emergency setting, a boy with a classical micturition syncope presentation (ie, first void after waking, while standing, with spontaneous recovery within a few minutes) with both normal clinical examination and electrocardiogram results and without any “red flags” can reasonably be discharged without any further examinations. | |
|
• “Red flags” for micturition syncope in childhood include (1) event history of exertional syncope or syncope precipitated by noise or emotion; (2) medical history of congenital heart disease, cardiac surgery, or Kawasaki disease; (3) known familial ventricular arrhythmias, sudden cardiac death, or unexplained death in a first- or second-degree relative before 50 years of age, or cardiomyopathy or heart failure in a first- or second-degree relative; and (4) cardiovascular examination findings of tachycardia or tachypnea, irregular cardiac rhythm, a pathological murmur (including a dynamic murmur), gallop, or click, or a loud or single second heart sound (S2). |
The diagnostic work-up varies by the clinical circumstances and the clinically suspected etiologies of micturition or defecation syncopes. Lung function, cardiac function, orthostatic pulse and blood pressure, and blood volume should be assessed clinically. An electrocardiogram should be obtained.
If the history and examination do not suggest an underlying significant comorbidity in a man with micturition syncope, particularly a man younger than 50 years of age, further diagnostic studies are usually unrevealing (47; 23; 38).
In an emergency setting, a boy with a classical micturition syncope presentation (ie, first void after waking, while standing, with spontaneous recovery within a few minutes) with both normal clinical examination and electrocardiogram results and without any “red flags” can reasonably be discharged without any further examinations (50). Proposed “red flags” for micturition syncope in childhood include (1) event history of exertional syncope or syncope precipitated by noise or emotion; (2) medical history of congenital heart disease, cardiac surgery, or Kawasaki disease; (3) known familial ventricular arrhythmias, sudden cardiac death, or unexplained death in a first- or second-degree relative before 50 years of age, or cardiomyopathy or heart failure in a first- or second-degree relative; and (4) cardiovascular examination findings of tachycardia or tachypnea, irregular cardiac rhythm, a pathological murmur (including a dynamic murmur), gallop, or click, or a loud or single second heart sound (S2) (50).
Additional studies should be considered selectively. Electroencephalography and echocardiography are usually normal in patients with micturition or defecation syncope. In selected cases, Holter monitoring can be helpful in identifying associated cardiac arrhythmias. In some patients with suspected vagally mediated arrhythmias, vagal maneuvers can be considered to determine if increased vagal tone can precipitate related clinical outcomes (eg, sinus arrest, atrioventricular block, hypotension, or syncope); such maneuvers can include carotid sinus massage and eyeball compression, but the vast majority of reported cases of micturition or defecation syncope did not have abnormal findings on such maneuvers. More sophisticated cardiac electrophysiologic studies are rarely needed. Tilt table testing may have some utility, possibly utilizing a series of Valsalva maneuvers, although available data are insufficient to recommend this as a routine study (63). The frequency of abnormal tilt table studies was more common in older patients (over 55 years of age) than in younger patients with micturition syncope (83), but it does not differ between patients with micturition and defecation syncope (41). To assess for possible bladder paraganglioma, plasma, and 24-hour urinary catecholamine levels should be obtained in patients with micturition syncope in association with hypertensive crises.
In an anecdotal report, a patient with defecation syncope associated with splanchnic sympathetic dysfunction had resolution of this problem after permanent pacemaker insertion (54).
Some cases of micturition or defecation syncope may require consultation by a gastroenterologist, cardiologist, general surgeon, or urologist, depending on the clinically suspected underlying etiologies identified.
Newer technology to noninvasively and simultaneously monitor cerebral hemodynamics, blood pressure, and other important parameters at high temporal resolution (250 Hz sampling rate) have been shown to be useful in preliminary studies (96).
Management
|
• Management of micturition and defecation syncope focuses on treatment of the underlying conditions. | |
|
• Men with recurrent micturition syncope should be encouraged to sit while urinating. | |
|
• Patients with micturition or defecation syncope may require management of orthostatic hypotension, cardiac arrhythmias, and other comorbid and contributing conditions. Those with micturition syncope may also require management of urologic disorders (including bladder outlet obstruction and urinary tract infections), whereas those with defecation syncope may require management of intestinal disorders, deep venous thromboses, and pulmonary emboli. | |
|
• For patients with micturition or defecation syncope, avoidance of excess alcohol should be strongly encouraged. | |
|
• No randomized controlled trials of pacing have been conducted in patients with micturition syncope, defecation syncope, or other situational syncopes, but results of randomized trials for vasovagal syncope are at best inconsistent, and there has been an increasing shift away from using pacing for such clinical situations. | |
|
• Surgery and adjuvant therapies are effective treatments for paraganglioma of the urinary bladder. |
Management of micturition and defecation syncope focuses on treatment of the underlying conditions.
Men with recurrent micturition syncope should be encouraged to sit while urinating (11). This not only lessens the likelihood of injury in the event of syncope but also helps to maintain blood pressure while voiding (11). Patients with micturition syncope, particularly older patients, may require management of orthostatic hypotension, cardiac arrhythmias, urologic disorders (including bladder outlet obstruction and urinary tract infections), and other comorbid and contributing conditions (57). Avoidance of excess alcohol should be strongly encouraged.
Patients with defecation syncope may require management of orthostatic hypotension, cardiac arrhythmias, intestinal disorders, deep venous thromboses and pulmonary emboli, and other comorbid and contributing conditions (39; 40). As in patients with micturition syncope, avoidance of excess alcohol should be strongly encouraged. A patient diagnosed with defecation syncope and splanchnic sympathetic dysfunction, with persistent bradycardia during symptom reproduction with colonoscopy, had resolution of symptoms with pacemaker implantation (54). Defecation syncope resulting from functional inferior vena cava obstruction can be relieved with mobilization of the inferior vena cava and crural myotomy (10). Defecation syncope related to structural gastrointestinal lesions (eg, Morgagni hernia, Meckel diverticulum, ruptured appendix, etc.) may require surgery (39; 92). Defecation syncope related to autonomic dysfunction in patients with end-stage liver disease may benefit from orthotopic liver transplantation (60).
No randomized controlled trials of pacing have been conducted in patients with micturition syncope, defecation syncope, or other situational syncopes, but results of randomized trials for vasovagal syncope are at best inconsistent, and there has been an increasing shift away from using pacing for such clinical situations (24; 12; 43). Permanent cardiac pacing should generally be reserved for patients with little or no prodrome and significant bradycardia or asystole at the time of syncope who have failed other interventions (53; 24). Other indications can include frequent cardioinhibitory syncope (more than five attacks per year), severe physical injury or accident, and age greater than 40 years (09; 08).
Surgery and adjuvant therapies are effective treatments for paraganglioma of the urinary bladder (an extra-adrenal catecholamine-producing tumor). These tumors can generally be completely resected via transurethral resection of bladder tumor, en bloc transurethral resection with thulium-YAG laser, or partial cystectomy (68; 95; 35; 84; 33; 86; 90). Compared with open surgery, laparoscopic partial cystectomy, and robot-assisted laparoscopic partial cystectomy are advantageous in the treatment of paraganglioma of the urinary bladder (95; 84; 33; 86; 90). Because bladder paragangliomas are likely to recur and metastasize, lifelong clinical follow-up, annual measurement of plasma and urinary catecholamine levels, and cystoscopy are essential (68).
Media
References
- 01
- Abe H, Kohno R, Oginosawa Y. Characteristics of syncope in Japan and the pacific rim. Prog Cardiovasc Dis 2013;55(4):364-9. PMID 23472772
- 02
- Alaklabi AM, Arabi TZ, Bin Saeedan MN, Alotaibi GS. A young patient with undiagnosed polycythemia-paraganglioma syndrome: a case report. Am J Case Rep 2023;24:e938676. PMID 37160900
- 03
- Altinsoy B, Erboy F, Tanriverdi H, et al. Syncope as a presentation of acute pulmonary embolism. Ther Clin Risk Manag 2016;12:1023-8. PMID 27390523
- 04
- Bae MH, Kang JK, Kim NY, et al. Clinical characteristics of defecation and micturition syncope compared with common vasovagal syncope. Pacing Clin Electrophysiol 2012;35(3):341-7. PMID 22188510
- 05
- Bagchi A, Dushaj K, Shrestha A, et al. Urinary bladder paraganglioma presenting as micturition-induced palpitations, dyspnea, and angina. Am J Case Rep 2015;16:283-6. PMID 25965060
- 06
- Bilbro RH. Syncope after prostatic massage. N Engl J Med 1970;282:167-8. PMID 5409547
- 07
- Birlutiu V, Birlutiu RM, Feiereisz AI. SARS-CoV-2 infection associated with micturition syncope: our experience with 4 case reports. Medicine (Baltimore) 2020;99(31):e21512. PMID 32756188
- 08
- Brignole M. Neurally-mediated syncope. Ital Heart J 2005;6(3):249-55. PMID 15875516
- 09
- Brignole M, Alboni P, Benditt D, et al. Guidelines on management (diagnosis and treatment) of syncope. Eur Heart J 2001;22(15):1256-306. PMID 11465961
- 10
- Brophy CM, Evans L, Sumpio BE. Defecation syncope secondary to functional vena caval obstruction during a Valsalva maneuver. Ann Vasc Surg 1993;7:374-7. PMID 8268080
- 11
- Chakravarty A. Why women do not get micturition syncope. A hypothesis. Med Hypotheses 2003;61:463-4. PMID 13679013
- 12
- Chen LY, Benditt DG, Shen WK. Management of syncope in adults: an update. Mayo Clin Proc 2008;83:1280-93. PMID 18990328
- 13
- Coggins CH, Lillington GA, Gray CP. Micturition syncope. Arch Intern Med 1964;113:14-8. PMID 14067586
- 14
- Collins RE, Fell RH, Lord PD. Electrocardiography during manual dilation of the anus. Br Med J 1973;2:457-9. PMID 4712484
- 15
- Deng JH, Li HZ, Zhang YS, Liu GH. Functional paragangliomas of the urinary bladder: a report of 9 cases. Chin J Cancer 2010;2:729-34. PMID 20663319
- 16
- Donker DN, Dobles de Medina EO, Kieft J. Micturition syncope. Electroencephalogr Clin Neurophysiol 1972;33:328-31. PMID 4114918
- 17
- Eason AA. Micturition syncope: an atypical case. Urology 1986;27:354-5. PMID 3962059
- 18
- Eberhart C, Morgan JW. Micturition syncope: report of a case. JAMA 1960;174:2076-7. PMID 13725545
- 19
- Etgen T, Neuberger HR. Reflexsynkope – oder mehr?: Iktale Asystolie! [Reflex syncope-or more?: Ictal asystole!]. Inn Med (Heidelb) 2022;63(10):1085-91. PMID 35925121
- 20
- Fagius J, Karhuvaara S. Sympathetic activity and blood pressure increases with bladder distention in humans. Hypertension 1989;14:511-7. PMID 2807512
- 21
- Fletcher GF, Earnest DL, Shuford WF, Wenger NK. Electrocardiographic changes during routine sigmoidoscopy. Arch Intern Med 1968;122:483-6. PMID 5721873
- 22
- Gaitatzis A, Petzold A. Recurrent laughter-induced syncope. Neurologist 2012;18(4):214-5. PMID 22735250
- 23
- Godec CJ, Cass AS. Micturition syncope. J Urol 1981;126:551-2. PMID 7288951
- 24
- Grubb BP. Clinical practice. Neurocardiogenic syncope. N Engl J Med 2005;352(10):1004-10. PMID 15758011
- 25
- Guttman L, Whitteridge D. Effects of bladder distention on autonomic mechanisms after spinal cord injuries. Brain 1947;70:361-404. PMID 18903252
- 26
- Hainsworth R. Pathophysiology of syncope. Clin Auton Res 2004;14 Suppl 1:18-24. PMID 15480926
- 27
- Haldane JH. Micturition syncope: two case reports and review of the literature. Can Med Assoc J 1969;101:53-4. PMID 5362301
- 28
- Hamilton WF, Woodbury RA, Harper HT Jr. Physiologic relationships between intrathoracic, intraspinal, and arterial pressures. JAMA 1936;107:853-6.
- 29
- Hamilton WF, Woodbury RA, Harper HT Jr. Arterial, cerebrospinal and venous pressures in man during cough and strain. Am J Physiol 1944;141:42-50.
- 30
- Harbord MG, Mitchell C. Reflex seizures induced by defecation, with an ictal EEG focus in the left frontotemporal region. Epilepsia 2002;43:946-7. PMID 12181018
- 31
- Haslam RH, Freigang B. Cough syncope mimicking epilepsy in asthmatic children. Can J Neurol Sci 1985;12(1):45-7. PMID 3978474
- 32
- Hassan M, Quereshi AH. Paraganglioma of the urinary bladder: A case report. J Pak Med Assoc 2024;74(3):570-2. PMID 38591300
- 33
- Hu LL, Guo ZQ, Dai P, Chen G, Tian T. Case report: partial cystectomy for pheochromocytoma of the urinary bladder: a case report and review of literature. Front Cardiovasc Med 2022;9:1092260. PMID 36601067
- 34
- John H, Jaeger P, Greminger P, Yalla SV. Micturition syncope as the presenting symptom in a patient with prostatic enlargement and obstruction. J Urol 1998;160:2156-7. PMID 9817351
- 35
- Johnson JT, Cherian KE, Kapoor N, Paul TV. Micturition syncope secondary to urinary bladder paraganglioma. BMJ Case Rep 2020;13(3):e233556. PMID 32169989
- 36
- Johnson RH, Eisenhofer G, Lambie DG. The effects of acute and chronic ingestion of ethanol on the autonomic nervous system. Drug Alcohol Depend 1986;18:319-28. PMID 3816527
- 37
- Kaplan C, Kocaman SA, Durakoglugil ME, Kaya E, Senol MG. Cardiac syncope due to pain: report of a case responsive to duloxetine treatment. Herz 2013;38(6):683-4. PMID 23588599
- 38
- Kapoor WN, Peterson JR, Karpf M. Micturition syncope: a reappraisal. JAMA 1985;253:796-8. PMID 3968817
- 39
- Kapoor WN, Peterson J, Karpf M. Defecation syncope: a symptom with multiple etiologies. Arch Intern Med 1986;146:2377-9. PMID 3778072
- 40
- Kollef MH, Schachter DT. Defecation syncope caused by pulmonary embolism. Ann Intern Med 1990;113:86. PMID 2350119
- 41
- Komatsu K, Sumiyoshi M, Abe H, et al. Clinical characteristics of defecation syncope compared with micturition syncope. Circ J 2010;74(2):307-11. PMID 20032564
- 42
- Kounis NG, Kenmure AC. Micturition syncope, hypokalemia, and atrial fibrillation. JAMA 1976;236:954. PMID 988898
- 43
- Kuriachan V, Sheldon RS. Current concepts in the evaluation and management of syncope. Curr Cardiol Rep 2008;10:384-90. PMID 18715535
- 44
- Lanska DJ. Ventricular asystole during vagus nerve stimulation for epilepsy in humans. Neurology 2000;54:775. PMID 10680832
- 45
- Lenci TD. Appearance of sick sinus syndrome after years of micturition syncope. Conn Med 1982;46:375-6. PMID 7116838
- 46
- Lukash WM, Sawyer GT, Davis JE. Micturition syncope produced by orthostasis and bladder distention. N Engl J Med 1964;270:341-4. PMID 14082263
- 47
- Lyle CB Jr, Monroe JT Jr, Flinn DE, Lamb LE. Micturition syncope: report of 24 cases. N Engl J Med 1961;265:982-6. PMID 14467564
- 48
- Maclean AE, Allen EV, Magrath TB. Orthostatic tachycardia and orthostatic hypotension: defects in return of venous blood to the heart. Am Heart J 1944;27:145-63.
- 49
- Martin GJ, Adams SL, Martin HG, Mathews J, Zull D, Scanlon PJ. Prospective evaluation of syncope. Ann Emerg Med 1984;13(7):499-504. PMID 6742551
- 50
- Marzuillo P, Guarino S, Tipo V, et al. Micturition syncope in childhood: how to recognize and manage it. Pediatr Emerg Care 2019;35(5):e86-9. PMID 29135903
- 51
- Mathias CJ, Deguchi K, Schatz I. Observations on recurrent syncope and presyncope in 641 patients. Lancet 2001;357:348-53. PMID 11210997
- 52
- McGuire J, Green RS, Haunstein V, et al. Bed pan deaths. Am Pract Dig Treat 1950;1:23-8. PMID 15403169
- 53
- Melby DP, Cytron JA, Benditt DG. New approaches to the treatment and prevention of neurally mediated reflex (neurocardiogenic) syncope. Curr Cardiol Rep 2004;6(5):385-90. PMID 15306096
- 54
- Newton JL, Allan L, Baptist M, Kenny R. Defecation syncope associated with splanchnic sympathetic dysfunction and cured by permanent pacemaker insertion. Am J Gastroenterol 2001;96:2276-8. PMID 11467679
- 55
- O’Connor VJ. Observations on the blood pressure in cases of prostatic obstruction. Arch Surg 1920;1:359-67.
- 56
- Ojea Calvo A, Rodriguez Iglesias B, Alonso Rodrigo A, et al. [Bladder paraganglioma]. Actas Urol Esp 1993;17:513-5. PMID 8237531
- 57
- Onishi T, Sakata Y, Yonemura S, Sugimura Y. Pheochromocytoma of the urinary bladder without typical symptoms. Int J Urol 2003;10(7):398-400. PMID 12823696
- 58
- Overton R. Micturition syncope: reports of two cases. J Iowa State Med Soc 1962;52:369-71. PMID 14482873
- 59
- Park J, Jang SY, Yim HR, et al. Gender difference in patients with recurrent neurally mediated syncope. Yonsei Med J 2010;51:499-503. PMID 20499413
- 60
- Parker BM, Bhatia S, Younossi Z, Henderson JM, Tetzlaff JE. Autonomic dysfunction in end-stage liver disease manifested as defecation syncope: impact of orthotopic liver transplantation. Liver Transpl Surg 1999;5(6):497-501. PMID 10545537
- 61
- Pathy MS. Defaecation syncope. Age Ageing 1978;7(4):233-6. PMID 83099
- 62
- Poleshuck VA. Prostatic prostration. N Engl J Med 1970;282:632. PMID 5413880
- 63
- Prakash ES, Pavithran P. A novel tilt table testing protocol for investigating patients suspected to have neurally mediated syncope. In J Cardiol 2007;121:315-6. PMID 17182134
- 64
- Prandoni P, Lensing AW, Prins MH, et al. Prevalence of pulmonary embolism among patients hospitalized for syncope. N Engl J Med 2016;375(16):1524-31. PMID 27797317
- 65
- Previnaire JG, Soler JM. Micturition syncope following intermittent catheterisation in a tetraplegic patient. Spinal Cord 2006;44(11):695-6. PMID 16462821
- 66
- Proudfit WL, Forteza ME. Micturition syncope. N Engl J Med 1959;260:328-31. PMID 13632886
- 67
- Prozan GB, Litman A. Post micturition syncope. Ann Intern Med 1961;54:82-9. PMID 13738271
- 68
- Priyadarshi V, Pal DK. Paraganglioma of urinary bladder. Urol Ann 2015;7(3):402-4. PMID 26229338
- 69
- Ranaweera M, Chung E. Bladder paraganglioma: A report of case series and critical review of current literature. World J Clin Cases 2014;2(10):591-5. PMID 25325073
- 70
- Richardson DW, Honour AJ, Fenton GW, et al. Variation in arterial pressure throughout the day and night. Clin Sci 1964;26:445-60. PMID 14191273
- 71
- Rugg-Gunn MA. Fits, faints and blackouts: review of causes of syncope and allied states in Naval personnel. J R Nav Med Serv 1946;32:232-56. PMID 20285629
- 72
- Sakakibara R, Hattori T, Kita K, Yamanishi T, Tasuda K. Urodynamic and cardiovascular measurements in patients with micturition syncope. Clin Auton Res 1997;7:219-21. PMID 9370067
- 73
- Schiavone A, Biasi MT, Buonomo C, et al. Micturition syncopes. Funct Neurol 1991;6(3):305-8. PMID 1743547
- 74
- Schoenberg BS, Kuglitsch JF, Karnes WE. Micturition syncope--not a single entity. JAMA 1974;229:1631-3. PMID 4408311
- 75
- Schartum S. Ventricular arrest caused by the Valsalva maneuver in a patient with Adams-Stokes attacks accompanying defecation. Acta Med Scand 1968;184:65-8. PMID 5703965
- 76
- Shaw EC, Young HH. Gradual decompression in chronic vesical distention. J Urol 1923;11:373-94.
- 77
- Sherer DM, Santoso P, Russel BA, Abulafia O. Micturition syncope during pregnancy. Obstet Gynecol 2005;105:485-6. PMID 15738012
- 78
- Sikirov B. Straining forces at bowel elimination. Isr J Med Sci 1989;25:55-6. PMID 2925364
- 79
- Sikirov BA. Cardio-vascular events at defecation: are they unavoidable. Med Hypotheses 1990;32:231-3. PMID 2398836
- 80
- Silk AD. Benign micturition syncope. Calif Med 1969;111:355-6. PMID 5348034
- 81
- Smolensky MH, Portaluppi F, Manfredini R, et al. Diurnal and twenty-four hour patterning of human diseases: cardiac, vascular, and respiratory diseases, conditions, and syndromes. Sleep Med Rev 2015;21:3-11. PMID 25129838
- 82
- Song IU, Kim JS, Kim YI, Lee KS. Bilateral subcortical border-zone infarction following episodes of prolonged defecation syncope. J Clin Neurosci 2009;16(2):346-7. PMID 19091574
- 83
- Sumiyoshi M, Abe H, Kohno R, et al. Age-dependent clinical characteristics of micturition syncope. Circ J 2009;73(9):1651-4. PMID 19597300
- 84
- Sunil VN, John K, Nawahirsha S, Iyyadurai R. Micturition syncope: a rare presentation of bladder paraganglioma. BMJ Case Rep 2020;13(9):e235353. PMID 32878856
- 85
- Tigga MP. An unusual case of defecation syncope. J Midlife Health 2019;10(2):99-100. PMID 31391761
- 86
- Tomkins M, McCabe M, Crowther S, et al. Bladder paraganglioma presenting as post-micturition syncope. Eur J Case Rep Intern Med 2022;9(9):003537. PMID 36299853
- 87
- Trivedi MK, Arora G. Micturition syncope with asystole in a paediatric patient. Cardiol Young 2021;31(4):661-2. PMID 33308342
- 88
- Uchiyama T, Sakakibara R, Asahina M, Yamanishi T, Hattori T. Post-micturitional hypotension in patients with multisystem atrophy. J Neurol Neursurg Psychiatry 2005;76:186-90. PMID 15654029
- 89
- Velibey Y, Guvenc TS, Ugur M, Guzelburc O, Eren M. Diaphragmatic cardiac compression mimicking defecation syncope: a case report. Ann Intern Med 2016;165(6):454-6. PMID 27018536
- 90
- Wang Z, Liu F, Li C, et al. Case report: octreotide plus CVD chemotherapy for the treatment of multiple metastatic paragangliomas after double resection for functional bladder paraganglioma and urothelial papilloma. Front Oncol 2023;12:1072361. PMID 36741690
- 91
- Wenzke KE, Walsh KE, Kalscheur M, et al. Clinical characteristics and outcome of patients with situational syncope compared to patients with vasovagal syncope. Pacing Clin Electrophysiol 2017;40(5):591-5. PMID 28244210
- 92
- White DC, McMahon R, Wright T, Eubanks WS. Laparoscopic repair of a Morgagni hernia presenting with syncope in an 85-year-old woman: case report and update on the literature. J Laparoendosc Adv Surg Tech A 2002;12(3):161-5. PMID 12184900
- 93
- Youssef M, Sewell J, Grills R. Unrecognised paraganglioma of the urinary bladder precipitating hypertensive crisis. BMJ Case Rep 2024;17(4):e259283. PMID 38684348
- 94
- Zangerle KF, Wolford R. Syncope and conduction disturbances following sublingual nifedipine for hypertension. Ann Emerg Med 1985;14:1005-6. PMID 4037465
- 95
- Zhai H, Ma X, Nie W, et al. Paraganglioma of the urinary bladder: a series of 22 cases in a single center. Clin Genitourin Cancer 2017;15(5):e765-71. PMID 28688872
- 96
- Zhang Q, Zhang N, Kang L, et al. Technology development for simultaneous wearable monitoring of cerebral hemodynamics and blood pressure. IEEE J Biomed Health Inform 2019;23(5):1952-63. PMID 30334773
- 97
- Ziemssen T, Reichmann H. Cardiovascular autonomic dysfunction in Parkinson's disease. J Neurol Sci 2010;289:74-80. PMID 19740484
- 98
- Zivin I, Rowley W. Psychomotor epilepsy with micturition. Arch Intern Med 1964;113:3-13. PMID 14067599
- 99
- Zou R, Wang S, Lin P, et al. The clinical characteristics of situational syncope in children and adults undergoing head-up tilt testing. Am J Emerg Med 2020;38(7):1419-23. PMID 31843331
Contributors
All contributors' financial relationships have been reviewed and mitigated to ensure that this and every other article is free from commercial bias.
Author
-
Douglas J Lanska MD MS MSPH
Dr. Lanska of the University of Wisconsin School of Medicine and Public Health and the Medical College of Wisconsin has no relevant financial relationships to disclose.
See Profile
Patient Profile
- Age range of presentation
-
- 6 to 65+ years
This is an article preview.
Start a Free Account
to access the full version.
-
Nearly 3,000 illustrations, including video clips of neurologic disorders.
-
Every article is reviewed by our esteemed Editorial Board for accuracy and currency.
-
Full spectrum of neurology in 1,200 comprehensive articles.
-
Listen to MedLink on the go with Audio versions of each article.
Questions or Comment?
MedLink®, LLC
3525 Del Mar Heights Rd, Ste 304
San Diego, CA 92130-2122
Toll Free (U.S. + Canada): 800-452-2400
US Number: +1-619-640-4660
Support: service@medlink.com
Editor: editor@medlink.com
ISSN: 2831-9125
Also in This Category
-
-
General Neurology
Hepatic encephalopathy
Oct. 23, 2024
-
General Neurology
Bowel dysfunction in neurologic disorders
Oct. 10, 2024
-
General Neurology
Coma due to primary brainstem and diencephalic lesions
Oct. 05, 2024
-
Neuro-Ophthalmology & Neuro-Otology
Giant cell arteritis
Sep. 25, 2024
-
Neuro-Ophthalmology & Neuro-Otology
Ischemic optic neuropathy
Sep. 25, 2024
-
Neuro-Ophthalmology & Neuro-Otology
Transient visual loss
Sep. 25, 2024
-
Neuro-Oncology
Vestibular schwannoma
Sep. 19, 2024