Bezold-Jarisch reflex – Cardiology Basics

Bezold-Jarisch reflex – Cardiology Basics Bezold-Jarisch reflex was described as a cardiovascular response to injection of veratrum alkaloids in experimental animals. It consisted of apnea, bradycardia and hypotension. It was first described by von Bezold in 1867 [1] and later confirmed by Jarisch [2]. The reflex depends on intact vagal nerves and is mediated through medullary centres controlling respiration, heart rate and vasomotor tone [3]. The afferent limb of the Bezold-Jarisch reflex is from the cardiac sensory receptors through the non-myelinated vagal afferent pathways. The left ventricle, particularly the inferoposterior wall is the main region where these sensory receptors are located. Stimulation of these inhibitory receptors by stretch, chemical substances or drugs increases parasympathetic activity and inhibits sympathetic activity [4]. Bezold-Jarisch reflex is thought to have a role in the genesis of bradycardia and hypotension inferior wall myocardial ischemia and infarction, bradycardia and hypotension during coronary angiography, exertional syncope in aortic stenosis and in the effect of digitalis [4]. It has also been invoked for the explanation of transient fall in heart rate during exercise in a patient who was thought to have coronary vasospasm with reversible perfusion defect in the inferior wall with Thallium 201 scintigraphy [5]. References von Bezold AV, Hirt L. Uber die physiologischen wirkungen des essigsauren veratrins. Untersuchungen aus de...
Source: Cardiophile MD - Category: Cardiology Authors: Tags: General Cardiology Source Type: blogs