Abstract & Commentary
Synopsis: The substantial differences in opinion concerning the need for revascularization prior to elective vascular surgery are present among cardiologists.
Source: PierpontGL, et al. Disparate Opinions Regarding Indications For Coronary Artery Revascularization Before Elective Vascular Surgery. Am J Cardiol. 2004; 94:1124-1128.
The increasing use of drug eluting stents has created a dilemma regarding the necessity for coronary revascularization prior to vascular surgery, since the intensive, uninterrupted antiplatelet therapy delays surgery 3-6 months. Thus, Pierpont and colleagues selected 12 cases from the Coronary Artery Revascularization Prophylaxis (CARP) VA study of the long-term benefit of preoperative coronary artery revascularization in high-risk patients undergoing elective vascular surgery. Three cases were randomly selected from each of the 4 study groups: percutaneous coronary intervention (PCI); coronary artery bypass surgery (CABG); PCI candidate randomized to medical therapy; and CABG candidates randomized to medical therapy. Summaries of these cases, including nuclear perfusion studies and coronary angiograms, were reviewed by 31 board certified cardiologists evenly recruited from California, New York, and the upper Midwest. Each reviewer gave an opinion as to whether preoperative revascularization was needed, using a 7-point scale ranging from 1 = no revascularization to 7 = revascularization strongly recommended. Also, preference for PCI or CABG was noted. In addition, the opinions of the 21 interventionalists were compared to the 10 noninterventionalists.
Results: Scores of 1 or 2 and 6 or 7 predominated, with few scores in the middle. So, to simplify, revascularization was recommended 40% of the time (6 or 7), no intervention 43% of the time (1 or 2), and equivocal recommendations (3, 4, 5) 15% of the time. To view the data another way, there was only a 46% chance that 2 cardiologists would agree on their recommendation. There was no difference in the recommendations of the interventionalists vs the noninterventionalists. Choice of procedure varied considerably with only 1 case showing 100% agreement. Pierpont et el concluded that substantial differences in opinion concerning the need for revascularization prior to elective vascular surgery are present among cardiologists.
Comment by Michael H. Crawford, MD
This small opinion survey is not the type of paper we usually cover, but I thought it highlighted some important issues in contemporary cardiology practice. First, the decision to recommend revascularization, whether by PCI or CABG, will now delay vascular surgery by 3-6 months. Thus, in urgent or emergent cases, this consideration is almost moot. In elective cases, this decision for revascularization effectively transfers the patient to the cardiologist’s care until vascular surgery can safely be performed.
In this study, 40% of the opinions were for revascularization, even though none of the patients met traditional criteria for revascularization, such as left main disease or severe angina, by study design.
The CARP patients all had high-risk features for coronary artery disease, and underwent coronary angiography by protocol because it was hypothesized that they may benefit from preoperative revascularization. Currently, no other randomized, controlled study has addressed this issue. So, cardiologists had no strong evidence to base their decision upon. Also, they did not follow ACC/AHA Guidelines, which state that revascularization should only be done in patients who would benefit from it independent of their vascular surgery. In the absence of data, some believe in revascularization and others do not, and this often drives their decision rather than guidelines.
The second issue is that outside a protocol, some of these patients may not have had catheterization or stress testing. In the face of these 3-6 month revascularization delays, should we even bother evaluating vascular surgery patients preoperatively, and just clear those who have no compelling clinical reason to undergo catheterization? Given the low incidence of death and myocardial infarction even in these high-risk patients with vascular disease (about 2% now), can any evaluation, revascularization strategy improve on these results? Clearly, the CARP data are anxiously awaited.
Dr. Crawford, Professor of Medicine, Chief of Clinical Cardiology University of California San Francisco, is Editor of Clinical Cardiology Alert.