SYNCOPE Sanjay P. Singh, MD Chairman & Professor, Department of Neurology. Syncope Syncope is a clinical syndrome characterized by transient loss of consciousness (TLOC) and postural tone that is most often due to temporary and selfterminating global cerebral hypoperfusion. SYNCOPE is a sudden and brief loss of consciousness associated with a loss of postural tone, from which recovery is spontaneous. 1
Syncope This definition differentiates syncope from other nonsyncopal TLOC attacks, eg, seizures are due to a primary electrical disturbance of cerebral function and not cerebral hypoperfusion. Equally important is the need to distinguish syncope from apparent loss of consciousness events (socalled syncope mimics or pseudosyncope); the latter includes cataplexy, drop attacks. Nonsyncopal Attacks 2
Causes of Syncope Decreased blood flow to the Brain. Primarily neurological problem seizure. Syncope Numbers The Framingham study reported an incidence of 6.2 per 1000 person years; cumulative incidence during 10 years was 6%. The cumulative incidence of syncope is 3 to 6 percent over 10 years, and 80 percent of patients have their first episode before 30 years of age. 3
Syncope Causes of Syncope 4
Neurally Mediated Syncope Most common and is seen primarily in young adults. Vasovagal. A reflex response causes vasodilation, bradycardia, and systemic hypotension leading to decreased cerebral blood flow. Neurally mediated syncope includes vasovagal syncope, situational syncope, and carotid sinus syndrome/hypersensitivity. Neurally Mediated Syncope Autonomic sympathetic nerves that constrict blood vessels and maintain blood pressure, in reflex syncope withdraw their input, and blood pressure falls. The vagus nerve which directly controls heart rate, can increase activity and cause the heart rate to fall (bradycardia). 5
Neurally Mediated Syncope Vasovagal Syncope 6
COUNTER PRESSURE MANEUVERS The leg crossing maneuver consists of crossing the legs in standing position with tensing of leg, abdominal, and buttock muscles. The legs are firmly squeezed together. Arm tensing consists of isometric contraction of the 2 arms accomplished by gripping one hand with the other and concurrently abducting the arms. Midodrine 2.5mg bid (or go upto 5mg bid) 7
Cardiac Causes of Syncope Cardiac Causes of Syncope 8
Orthostatic Hypotension Orthostatic Hypotension Tx. The principal treatment strategy in drug induced ANF is elimination of the offending agent. Expansion of extracellular volume is an important goal. In the absence of hypertension, patients should be instructed to take sufficient salt and water intake, targeting 2 3 L of fluids per day and 10 g of NaCl.178 Rapid cool water ingestion is reported to be effective in combating orthostatic intolerance and post prandial hypotension. 9
Orthostatic Hypotension Tx. Gravitational venous pooling in older patients can be treated with abdominal binders or compression stockings. α agonist, midodrine, is a useful addition to the first line treatment in patients with chronic ANF. Midodrine (5 20 mg, three times daily) has been shown to be effective in three randomized placebo controlled trials. Orthostatic Hypotension Tx. Fludrocortisone (0.1 0.3 mg once daily) is a mineralocorticoid that stimulates renal sodium retention and expands fluid volume. The evidence in favour of fludrocortisone is from two small observational studies. Sleeping with the head of the bed elevated (108) prevents nocturnal polyuria, maintains a more favourable distribution of body fluids, and ameliorates nocturnal hypertension. 10
Syncope Investigations 11
Tilt testing enables the reproduction of reflex syncope in a laboratory setting. Positive responses in patients with neurally mediated syncope are 61 69% and specificity is high (92 94%). the patient is tilted upright for 20 to 45 minutes, usually at an angle of 60 to 80. TILT Table Test 12
13
Neurological SEIZURE Brain Cells [Neurons] : talk to one another via electrical discharges. 14
SEIZURE * Abnormal electrical discharges result in a seizure. * 2 Seizures Epilepsy. EPILEPSY Seizures Abnormal electrical discharge in the brain leading to a change in behavior. Epilepsy chronic disorder with spontaneous seizures. 15
16
MRI Brain. Seizure Investigations EEG Video EEG monitoring Seizure Treatment Antiepileptic medications Epilepsy Surgery Vagal Nerve Stimulator 17
Stroke TIA Anterior, Middle & Posterior Cerebral Artery 18
Homunculus 19
Vertebro-Basilar Insufficiency - Brainstem & Cerebellar signs Diplopia Dysphagia Dysarthria Dizziness Cranial nerve palsies Cerebellar cerebellar signs. Stroke Work up MRI Brain DWI is the most senstive MRA Head & Neck Echo. TEE vs TTE EKG Carotid Doppler 20