Clinical judgment an important predictor of successful outcomes in multivessel coronary disease

Sao Paulo, Brazil - Results from a new study have confirmed what some cardiologists have long suspected: the doctor really does know best ^[1]. Data from the Medicine, Angioplasty, or Surgery Study II (MASS II) suggest that physician judgment remains an important predictor of clinical outcomes.

"The fact that the clinical decision was collected before randomization in the MASS II trial allows a unique overview of the selection process and outcome in patients with stable multivessel CAD without left ventricular dysfunction. . . . Our data suggest that the best treatment option for individuals with multivessel CAD and preserved left ventricular function defined by the physician is a predictor of the incidence of cardiovascular events, mainly because of the need for additional revascularization procedures," writes lead investigator Dr Alexandre Pereira (Sao Paulo Medical School, Brazil) in the August 28, 2006 issue of the Journal of the American College of Cardiology.

In their paper, the authors write that no clear consensus exists about the best treatment for patients with stable multivessel CAD and preserved heart function. One-year follow-up data from MASS II showed that medical treatment for CAD was associated with a lower incidence of short-term events and a reduced need for additional revascularization. Surgery, on the other hand, was superior to medical therapy for alleviating anginal symptoms. All three therapies—medical therapy, surgery, and PCI—yielded low rates of cardiac-related deaths.

In this new analysis, investigators evaluated the outcomes of physician-guided treatment vs random assignment to therapy in the MASS II study. In total, the preferred treatment approach was obtained for each of the 611 randomized patients prior to randomization in the study. Those randomized to the same therapy the physician preferred were categorized as concordant, whereas those randomized to a therapy different from the preferred clinical approach of two cardiologists were classified as discordant. Overall, 48.2% of subjects received the therapy preferred by the two attending physicians.

Results showed that there was significantly more cardiac death, MI, or recurrent angina among the discordant patients (p=0.02) when compared with patients who were randomized to the same therapy preferred by the doctor. The end point explaining the difference was a significant shift toward more recurring refractory angina requiring revascularization (p=0.007). When investigators stratified their analysis into different treatment options, there were no observed differences in events between the concordant and discordant patients in the surgical or medical-therapy treatment arms, but there was a significant difference among patients who underwent PCI.

"It seemed that physicians could identify those patients who would do well with PCI," write the authors. Although the study did not include the use of drug-eluting stents, Pereira and colleagues note that even without these newer stents, the data are reassuring that PCI is a good treatment alternative for multivessel CAD patients whenever it is deemed to be clinically appropriate.

Angiographic variables, identified by the physicians but not captured by the inclusion criteria, were identified as the variables more often used in making clinical decisions regarding PCI. Notably, the presence of three-vessel disease was a significant predictor of discordance. Nearly half of concordant PCI patients had three-vessel disease, suggesting a more complex assessment of PCI feasibility, write investigators.

In an editorial accompanying the published study, Dr Ori Ben-Yehuda (University of California, San Diego) points out that no other field of medicine has embraced clinical trials as has cardiovascular medicine, leading to the advent of emphasis on evidence-based medicine ^[2]. With these trials, particularly comparisons between PCI and surgery, there is, assuming similar baseline clinical characteristics, an assumption that both treatments would be appropriate. However, the physician and patient preference might include factors that go beyond those included in the clinical-trial criteria and might have biologic significance.

"Some of these may simply reflect the overly simplistic assessment of coronary anatomy inherent in clinical-trial criteria compared with the individualized reading of angiograms, more fully reflective of each patient's unique anatomy," writes Ben-Yehuda. "Moreover, our decisions are often guided by our overall experience and the 'gestalt' of the patient's suitability for the procedure. Is there room, therefore, in this evidence-based era for individual physician and patient judgment?"

While Ben-Yehuda does not answer this question, he writes that registries of the Emory Angioplasty versus Surgery (EAST) and Bypass Angioplasty Revascularization Investigation (BARI) studies both suggest that physician judgment can affect successful outcomes, at least in these studies comparing surgery and PCI. He adds that these data are reassuring in that there remains a role for the "art of medicine." He notes that MASS II is limited by the relatively small sample size and lack of drug-eluting stents. Moreover, the possible role of patient judgment was not evaluated, another factor that might influence outcomes.