Objectifying the level of incomplete revascularization by residual SYNTAX score and evaluating the impact of incomplete revascularization on exercise tolerance in patients with coronary atherosclerotic heart disease treated by percutaneous coronary intervention

The prognostic impact of incomplete revascularization (ICR) on patients underwent percutaneous coronary intervention (PCI) was vague. Our research aimed to objectify the level of ICR by residual SYNTAX score (rSS) and evaluate the impact of ICR on exercise tolerance. We enrolled 87 patients who completed cardiopulmonary exercise testing (CPET) within 12 months after PCI, retrospectively. According to rSS, patients were divided into rSS = 0 group, 0 < rSS ≤ 8 group, and rSS > 8 group. The CPET variables--including peak metabolic equivalent (MET(peak)), percentages of predicting value of MET(peak) (MET(peak)%pred), MET at anaerobic threshold (AT), peak oxygen uptake (VO(2peak)), percentages of predicting value of VO(2peak) (VO(2peak)%pred), VO(2) at AT--were collected and compared. Among rSS = 0, 0 < rSS ≤ 8 and rSS > 8 groups, patients with higher rSS had progressively lower MET(peak), MET(peak)%pred, VO(2peak)%pred, VO(2) 1. There was no significant difference in exercise tolerance between rSS = 0 and 0 < rSS ≤ 8 groups. However, the exercise tolerance of patients in rSS = 0 and 0 < rSS ≤ 8 groups was better than that of patients in rSS > 8 group; 2. rSS was an independent risk factors for reduced exercise tolerance.