RÉSUMÉ
AIMS: To define a benchmark target for an invasive strategy (IS) rate appropriate for performance assessment in intermediate-to-high risk non-ST-segment elevation acute coronary syndromes (NSTE-ACS). METHODS AND RESULTS: During the BLITZ-4 campaign, which aimed at improving the quality of care in 163 Italian coronary care units, 4923/5786 (85.1%) of consecutive patients admitted with NSTE-ACS with troponin elevation and/or dynamic ST-T changes on the electrocardiogram were managed with IS. The reasons driving the choice (RDC) for a conservative strategy (CS) in the remaining 863 patients were prospectively recorded. In 33.8%, CS was mandatory because of patients refusal, known coronary anatomy or death before coronary angiography; in 52.8% it was clinically justified because of active stroke, bleeding, advanced frailty, severe comorbidities, contraindication to antiplatelet therapy or because they were considered to be at low risk; only in 13.4% the reasons, such as renal failure, advanced age or other, were less stringent. As compared to patients undergoing IS, those in the CS were 12years older and had significantly more severe comorbidities. The in-hospital and 6-month all-cause mortality were 9.0% vs 0.9% and 22.0% vs 3.9% in CS and IS groups respectively (p<0.0001 for both). CONCLUSION: As the RDC for CS were clinically correct in vast majority of cases the observed 85% invasive strategy rate may be considered as the desirable benchmark target in patients with NSTE-ACS. For the same reason, it remains questionable if the higher rate of IS could have improved the prognosis in CS patients, despite their highly unfavorable prognosis.