Patients enrolled in coronary intervention trials are not representative of patients in clinical practice: results from the Euro Heart Survey on Coronary Revascularization

AIMS: Revascularization in patients with coronary artery disease changed over the last two decades, favouring the number of patients treated by means of percutaneous coronary interventions (PCI) when compared with coronary artery bypass grafting (CABG). Many randomized controlled trials (RCTs) have been performed to compare these two competing revascularization techniques. Because of the strict enrolment criteria of RCTs in which highly selected patients are recruited, the applicability of the results may be limited in clinical practice. The current study evaluates to what extent patients in clinical practice were similar to those who participated in RCTs comparing PCI with CABG. METHODS AND RESULTS: Clinical characteristics and 1-year outcome of 4713 patients enrolled in the Euro Heart Survey on Coronary Revascularization were compared with 8647 patients who participated in 14 major RCTs, comparing PCI with CABG. In addition, we analysed which proportion of survey patients would have disqualified for trial participation (n=3033, 64%), aiming at identifying differences between trial-eligible and trial-ineligible survey patients. In general, important differences were observed between trial participants and survey patients. Patients in clinical practice were older, more often had comorbid conditions, single-vessel disease, and left main stem stenosis when compared with trial participants. Almost identical differences were observed between trial-eligible and trial-ineligible survey patients. In clinical practice, PCI was the treatment of choice, even in patients who were trial-ineligible (46% PCI, 26% CABG, 28% medical). PCI remained the preferred treatment option in patients with multi-vessel disease (57% in trial-eligible and 40% in trial-ineligible patients, respectively, P<0.001); yet, the risk profile of patients treated by PCI was better than that for patients treated either by CABG or by medical therapy. In the RCTs, there was no mortality difference between PCI and CABG. In clinical practice, however, we observed 1-year unadjusted survival benefit for PCI vs. CABG (2.9 vs. 5.4%, P<0.001). Survival benefit was only observed in trial-ineligible patients (3.3 vs. 6.2%, P<0.001). CONCLUSION: Many patients in clinical practice were not represented in RCTs. Moreover, only 36% of these patients were considered eligible for participating in a trial comparing PCI with CABG. We demonstrated that RCTs included younger patients with a better cardiovascular risk profile when compared with patients in everyday clinical practice. This study highlights the disparity between patients in clinical practice and patients in whom the studies that provide the evidence for treatment guidelines are performed.