Name
CAROTID SINUS SYNDROME
DESCRIPTION
DETAIL
CAUSES : β’ Idiopathic β’ Stimulation of the hypersensitive Baroreceptors in the carotid sinus affects vagus and sympathetic nerve outflow β’ Carotid body tumors β’ Inflammatory and malignant lymph nodes in the neck β’ Metastatic cancer β’ Coronary artery disease -------------------------------------------------------------------------- DIFFERENTIAL DIAGNOSIS β’ Vasovagal syncope β’ Postural hypotension β’ Primary autonomic insuffi ciency β’ Hypovolemia β’ Arrhythmias β’ Sick sinus syndrome β’ Syncope secondary to reduced cardiac output β’ Cerebrovascular insuffi ciency β’ Emotional disturbances β’ Other causes of syncopeSPECIAL TESTS: With the patient in the supine position and while the ECG is monitored, manual massage of the carotid sinus causes asystole of more than 3 seconds (cardioinhibitory) and/or a drop in systolic BP DIAGNOSTIC PROCEDURES : β’ Carotid sinus massage (check for potential contraindications before performing massage including carotid bruits, known carotid hypersensitivity, demonstrated carotid artery disease) β’ Electrophysiologic studies β’ Electrocardiogram β’ Carotid duplex scan
TYPENOTES
RISK FACTORS : Diffuse atherosclerosis, Wearing tight collars, Shaving over region of carotid sinus, Emotional upheaval, Head movementGENERAL MEASURES : Cardiac pacing (dual chamber) is the treatment of choice SURGICAL MEASURES : β’ Carotid sinus denervation (CSD) by surgery or radiation therapy for selected patients β’ Dual chamber pacemaker helps in preventing recurrent symptoms in patients with cardioinhibitory component β’ Surgery for selected patients with atheromata PATIENT EDUCATION : Avoidance of exacerbating factors that might stimulate the carotid sinus - tight neck collar, shaving, turning of the head to one side, straining at stool DRUG(S) OF CHOICE : β’ Anticholinergics - atropine for the cardioinhibitory type β’ Sympathomimetics - ephedrine β’ Theophylline β’ In one recent study, SSRIs were successful in controlling symptoms PRECAUTIONS: Concomitant usage of digitalis, beta-blockers, clonidine and alpha-methyldopa may accentuate response to carotid sinus massage PREVENTION/AVOIDANCE: β’ Avoidance of pressure on the neck β’ Support hose may be helpful for some patients with vasodepressor type POSSIBLE COMPLICATIONS : β’ Prolonged confusion β’ Frequent falls leading to injuries and fractures EXPECTED COURSE/PROGNOSIS: Serious if syncope associated with atheromatous narrowing of sinus artery or basilar artery
RELATED DISEASE
Not Available Disease
DISEASE
INVESTIGATION
COMPLETE BLOOD COUNT, ECG, ELECTROPHYSIOLOGIC STUDY