Discussion
Anomalous origins of coronary arteries are infrequent phenomena within the general population, and seldomly encountered at time of heart transplantation. Because left heart catherization is not routinely performed as part of the standard evaluation of donor grafts, unless the donor is male and older than 45 (or >50 years for female donors) or other concerns for possible coronary artery disease exist, these findings are typically unknown prior to procurement. Several reports2–4 have documented the use of donor heart grafts with anomalous coronary anatomy. However, in most cases, these findings are often not recognized until the time of in-person donor evaluation, or even after donor cardioectomy. In this case, left heart catheterization was performed prior to evaluation by the surgical team, and thus, the diagnosis of single coronary artery was known beforehand.
Various variations of aberrant coronary anatomy exist, all with separate risk profiles. The most lethal variant described is the LCA originating from the right coronary sinus with an inter-arterial course, which carries the highest risk of sudden or exercise-induced death, particularly in younger patients.5 As in our case, a retro-aortic course of an aberrant coronary is generally thought to have no hemodynamic consequence.6 Given these facts, we felt this anatomy to be a benign variation and a suitable graft for this recipient – a gentleman of increased age and with prolonged hospital course. Given the fact the patient remained hospital-dependent for more than 4 months awaiting a heart offer, the benefits of transplantation of this donor graft appeared to outweigh the risks of continued hospitalization and waiting. Given the coronary anatomy, implantation of the cardiac graft did not require modification from usual practice, unlike that of Vasseur and colleagues, who applied a slight modification using a shorter pulmonary artery trunk and longer aortic trunk to create a wide aorto-pulmonary window for implantation of a graft with an inter-arterial LCA.3
Though a relatively uncomplicated immediate posttransplant course, it is unclear how this graft may perform in the long-term. A previous retrospective analysis1 has suggested that perhaps anomalous coronary artery patters may demonstrate a higher prevalence of significant atherosclerosis, however, little is known about the development of chronic allograft vasculopathy within a transplanted graft.