To the Editor:
Drs Reese and Beckman correctly point out that there is a lack of clinical trial evidence for evaluating renal transplant recipients. They are concerned, however, that pre-operative testing may result in harmful side effects. In particular, their concern is that routine stress tests will result in angiography and revascularization with associated complications. The review (1), however, states clearly that revascularization should not be offered automatically to patients in whom there is no clear survival benefit and advocates diagnosing coronary artery disease (CAD) and conservative treatment known to benefit those with CAD, rather than revascularization in the absence of a known clinical benefit.
Although the definition of high risk in the review differs from that listed by the American College of Cardiology (ACC) Guideline (2), the factors in Table 1 are consistent with recently published guidelines for high-risk patients in the setting of renal transplantation (3). While the risk of perioperative mortality is low after renal transplantation, this may well be due to the exclusion of high-risk patients. Interestingly, although the definitions of high- and intermediate-risk patients recommended by the American College of Cardiology differ from those in the renal transplant literature, the ACC guidelines advocated by Drs Reece and Beckman suggest exercise or pharmacological testing in patients with an intermediate pre-test probability of CAD (patients with renal dysfunction and diabetes) indicating that there is Class I evidence for this decision. Thus the approaches in the ACC guidelines and my review do not differ significantly.
The suggestions in the review in no way intend to reduce access to renal transplantation. Currently, the revascularization of asymptomatic patients with coronary stenoses prior to transplantation is mandatory in some transplant units. This is based on limited evidence (4). There are data suggesting that successful renal transplantation confers a cardiovascular benefit and therefore, mandating revascularization of stenoses that are not life-threatening and potentially delaying transplantation does not appear warranted.
The correspondence highlights the need for trials in the areas of screening and treatment of coronary artery disease in this high-risk group of patients. Until these are available, cardiac screening of high-risk patients is appropriate, while revascularization of stenoses in the absence of a survival benefit is not warranted in patients approaching renal transplantation.