Perspective:

This study demonstrates that CCTA and SPECT can be useful in evaluating patients prior to renal transplant, but highlights the limitations of such study designs. CCTA has excellent sensitivity and SPECT has poor sensitivity if our question is: ‘Does this patient have a coronary stenosis ≥50%?’ The problem here is that many lesions with a stenosis ≥50% will not result in ischemia. Further, many lesions with anatomic stenosis and ischemia may not merit revascularization. These results don’t really answer our clinical question. The real question is: ‘Does this patient need revascularization prior to renal transplant?’ This study does not provide data on the accuracy of these tests to identify a stenosis ≥70% (or left main stenosis ≥50%), and more importantly, does not provide data on which of these tests was most likely to identify patients who merited consideration of revascularization. It is also notable that the majority of patients (57%) had stage 5 chronic renal insufficiency, but were not yet on dialysis. While the authors stated that acetylcysteine was administered to ‘prevent contrast-induced nephropathy,’ there are conflicting data on its effectiveness. Although the 11 patients started on dialysis after the CCTA or invasive angiography did not have this attributed to contrast-induced nephropathy, I cannot understand why we would ever use a nephrotoxic test in this population when tests that present no risk of accelerating a need for dialysis are available. While there appears to be a role for both CCTA and SPECT in this population, these results raise more questions than answers.