A RANDOMIZED COMPARISON OF THE EFFECTS OF GRADUAL PROLONGED VERSUS STANDARD PRIMARY BALLOON INFLATION ON EARLY AND LATE OUTCOME - RESULTS OF A MULTICENTER CLINICAL-TRIAL

Background Observational studies have suggested that prolonged balloon inflation during coronary angioplasty is associated with a high clini cal success rate. This randomized clinical trial sought to evaluate th e impact of primary gradual and prolonged inflations versus standard s hort dilatations in patients undergoing elective angioplasty. Methods and Results In phase 1 of the study, patients were randomized to recei ve two to four standard (1 minute) dilatations or one or two prolonged (15 minutes) dilatations after a perfusion balloon had been placed ac ross a single target lesion. Patients with unsuccessful angiographic a ppearance after phase 1 dilatations had further dilatations in phase 2 . Patients were followed for 6 to 12 months after the procedure. Of 47 8 patients, 242 received a median of one prolonged dilatation of 15 mi nutes' duration, and 236 received three dilatations for a median of 1 minute. Patients assigned to prolonged dilatations had a higher succes s rate (less than or equal to 50% residual visual stenosis) (95% versu s 89%; P=.016), less severe residual stenosis by quantitative angiogra phy (median [25th and 75th percentiles], 35% [26%, 42%] versus 38% [30 %, 46%]; P=.001), and a lower rate of major dissections (3% versus 9%; P=.003) at the end of phase 1. A total of 114 patients had further di latations in phase 2 - 43 in the prolonged arm and 71 in the standard arm. The final procedural success rate was 98% with both primary dilat ation strategies, which included additional maneuvers such as prolonge d dilatations in the patients randomized to the primary standard dilat ation. Overall, 320 of 416 patients (77%) who were discharged after a successful procedure without any in-hospital event (death, myocardial infarction, coronary artery bypass graft surgery, abrupt closure, or r epeat angioplasty in target vessel) returned for follow-up angiography . The restenosis rate (>50% residual visual stenosis) was 44% (95% con fidence interval, 37% to 52%) in the prolonged dilatation group and 44 % (36% to 52%) in the standard dilatation group. The primary angiograp hic end point of failure at the end of phase 1, abrupt closure, or res tenosis throughout the study period was similar in both groups (prolon ged, 51%; standard, 49%; P=.62). The secondary end point of absence of clinical events (death, nonfatal myocardial infarction, coronary arte ry bypass graft surgery, or repeat angioplasty in target vessel) also was similar (prolonged, 66%; standard, 74%; P=.15). Conclusions Primar y gradual and prolonged dilatations caused less arterial trauma with a modestly larger arterial lumen compared with standard dilatations. Th is initial improvement in angiographic appearance did not lead to a si gnificant reduction in restenosis or clinical adverse events during fo llow-up.