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Recurrent syncope due to carotid sinus hypersensitivity and sick sinus syndrome
Feng-Yu Kuo1, Hsiang-Chiang Hsiao, Chuen-Wang Chiou
1Cardiovascular Medical Center, Kaohsiung Veterans General Hospital, Kaohsiung, Taiwan, ROC.
Abstract:
Syncope is a sudden and brief loss of consciousness with postural tone. Its recovery is usually spontaneous. There are various causes of syncope including cardiac, vascular, neurologic, metabolic and miscellaneous origins. The tracing is usually time-consuming and costly. The diagnosis of carotid sinus syncope may sometimes be difficult since the symptoms are nonspecific, especially in older persons. Here, we report the case of a 72-year-old woman who sought medical attention at our hospital due to repeated syncope episodes over the previous 5 years. Neurologic examinations showed negative results (including brain computed tomography). Twenty-four-hour ambulatory electrocardiogram monitoring showed atrial and ventricular premature contractions only. Electrophysiologic study disclosed prolonged corrected sinus node recovery time (1,737 ms) with poor atrioventricular conduction. Drop of blood pressure together with sinus bradycardia developed after left side carotid sinus massage. Both carotid sinus hypersensitivity with sick sinus syndrome contributed to this patient's syncope, and after pacemaker placement together with selective serotonin reuptake inhibitor treatment, she was free from syncope thereafter.
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