Coronary Spasm in Neurosurgical Patients and Role of Trigeminocardiac Reflex

Abstract

Background. Coronary artery spasm (CAS) is a rarely reported complication in neurosurgical patients and its main causative mechanism was attributed to vagal mediated responses. However, these may be the unusual manifestations of trigeminal cardiac reflex (TCR) which is a well established brain stem reflex observed in various neurosurgical patients. Methods and Results. In this review, we have searched for the case reports/papers related to intraoperative coronary spasm in neurosurgical patients and described the role of TCR in this regard. TCR is a possible mechanism in producing CAS in most of the cases in which stimulation occurred at or near the vicinity of trigeminal nerve. It is likely that TCR mediated coronary spasm may be a physiological mechanism and not related to actual myocardial insult apparent by cardiac enzymes or echocardiography studies in most of the cases. Some common risk factors may also exist related to occurrence of CAS as well as TCR. Conclusions. In conclusion, neurosurgical procedures occurring at the vicinity of trigeminal nerve may produce CAS even in previously healthy patients and may produce catastrophic consequences. There is a need for future reports and experimental studies on the interaction of TCR and pathophysiological mechanisms related to CAS.

The negative chronotropic effect during lumbar spine surgery

“…The most common postulation is the activation of parasympathetic nerves that causes these adverse changes in HR similar to vasovagal reflex. The mechanical stretch of the spinal dura with its intrinsic and extrinsic innervation [19] is the most potent provoking factor in inciting this reflex. As in every reflex, also this spinal reflex has a certain threshold from which the reflex will be triggered, explaining that not every dural manipulation will lead to a reflex response.…”

Republished: Trigeminocardiac reflex caused by selective angiography of the middle meningeal artery

“…Fortunately, in our case the symptoms were temporary but, in some cases, a TCR may develop into severe bradycardia or even asystole and arterial hypotension which require intervention. Coronary artery spasms provoked by TCR have been reviewed 11. Care should be taken with ST changes, ventricular fibrillation, ventricular tachycardia, atrioventricular block and myocardial infarction as accompanying manifestations of TCR.…”

The Trigeminocardiac Reflex in Neurological Disorders

“…The central and peripheral TCRs are well-established brain stem reflexes that can cause these perturbations. 22 A wide array of cardiovascular changes pertaining to coronary artery spasm (such as bradycardia, ST changes, atrioventricular block, tachycardia, ventricular fibrillation, hypertension, and hypotension) in patients undergoing neurosurgical procedures has been most commonly attributed to vagal stimulation. [23][24][25][26][27][28] However, the vagal reflex is a part of the TCR, which is initiated by stimulation of branches of the trigeminal nerve or ganglion along its course and is relayed via the vagus nerve.…”