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 in 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

  1. von Bezold AV, Hirt L. Uber die physiologischen wirkungen des essigsauren veratrins. Untersuchungen aus dem Physiologischen Laboratorium Wurzburg 1867; 1: 75-156.
  2. Jarisch A, Richter H. Die afferenten bahnen des veratrine effektes in den herznervenArchiv Für Experimentelle Pathologie Und Pharmakologie, 1939; 193, 355-371.
  3. Aviado DM, Guevara Aviado D. The Bezold-Jarisch reflex. A historical perspective of cardiopulmonary reflexes. Ann N Y Acad Sci. 2001 Jun;940:48-58. PMID: 11458703.
  4. Mark AL. The Bezold-Jarisch reflex revisited: clinical implications of inhibitory reflexes originating in the heart. J Am Coll Cardiol. 1983 Jan;1(1):90-102. doi: 10.1016/s0735-1097(83)80014-x. PMID: 6826948.
  5. Sakai C, Kawasaki T, Sugihara H, Matoba S. The Bezold-Jarisch reflex in a patient with coronary spastic angina. Ann Noninvasive Electrocardiol. 2020 Nov;25(6):e12759. doi: 10.1111/anec.12759. Epub 2020 Apr 26. PMID: 32335982; PMCID: PMC7679827.