【內科部 GrandRound】

日期: 113年 03月 19日   地點:B1 第一演講廳

主題: 

Uncommon forms of reflex syncope

講者: 心臟內科外賓Prof. David Benditt

大綱:

Syncope is a clinical syndrome in which transient loss of consciousness (TLOC) is caused by a period of inadequate cerebral blood flow, caused most often by an abrupt drop of systemic blood pressure. Reflex syncope (previously termed neurally mediated syncope) is a condition in which a reflex response causes vasodilatation and/or bradycardia. The heart rate slowing may or may not be profound but results in a heart rate that is slower than appropriate for the falling blood pressure, leading to systemic hypotension and cerebral hypoperfusion with TLOC. Types of reflex syncope include vasovagal syncope (eg, cough syncope, deglutition syncope, and others), situational syncope, carotid sinus syncope, and some cases without apparent triggers. Vasovagal syncope is by far the most common type of syncope across all age groups.

Uncommon forms of reflex syncope pose diagnostic dilemmas due to their heterogeneous presentations and variable triggers. Differential diagnosis often necessitates meticulous history-taking, detailed autonomic function testing, and occasionally, specialized tilt-table testing or carotid sinus massage. Management strategies encompass a multifaceted approach, including patient education, lifestyle modifications, pharmacotherapy, and in select cases, invasive interventions such as pacemaker implantation or carotid sinus denervation.

In conclusion, while vasovagal syncope represents the archetypal form of reflex syncope, several uncommon variants exist, each characterized by distinct triggers and clinical features. Enhanced recognition and understanding of these less prevalent forms are imperative for accurate diagnosis and tailored management, thereby optimizing patient outcomes and minimizing the burden of syncope-related morbidity and mortality. Further research endeavors are warranted to elucidate the underlying pathophysiological mechanisms and refine therapeutic strategies for these intricate syndromes.