Myocardial bridging in the era of a drug epidemic: A case report addressing the need to revisit donor organ assessment

Abstract

Background Myocardial bridging (MB), though typically a benign finding, may occasionally lead to syncope, myocardial infarction, arrhythmia, or sudden death. Surgical denervation of transplanted hearts complicates the management of such incidentally detected post-transplant coronary anomalies due to the lack of classic ischaemic symptoms. Case summary A middle-aged female underwent an uncomplicated cardiac transplantation from a healthy male donor in his early 20s who had suffered a cardiac arrest while using cocaine. Given the young donor age, a pre-transplant coronary angiogram (CAG) was deferred. However, 6-week post-transplant, routine CAG, and intravascular ultrasound revealed an extensive MB spanning a significant portion of the left anterior descending coronary artery with substantial myocardium at risk. A stress test with myocardial perfusion imaging performed to evaluate the functional significance of the bridge did not reveal any perfusion abnormalities in the myocardium at risk. Discussion In current practice, younger donors often do not undergo pre-transplantation CAG routinely performed in older donors given the lower prevalence of significant coronary disease. However, post-operatively this young donor was found to have passed on a potentially life-threatening MB to a denervated recipient, who cannot manifest typical anginal symptoms during ischaemia, thereby challenging providers to choose among strategies of watchful waiting, risk stratification, or pre-emptive intervention. In retrospect, the donor's mode of death may have signalled an underlying structural abnormality that warranted further pre-transplant characterization. In order to ensure optimal quality of transplanted hearts, young donors may warrant pre-transplant CAG despite their age, particularly those with a history of drug use or suspicious mode of death.