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.