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 (METpeak), percentages of predicting value of METpeak (METpeak%pred), MET at anaerobic threshold (AT), peak oxygen uptake (VO2peak), percentages of predicting value of VO2peak (VO2peak%pred), VO2 at AT--were collected and compared.Among rSS = 0, 0 < rSS ≤ 8 and rSS > 8 groups, patients with higher rSS had progressively lower METpeak, METpeak%pred, VO2peak%pred, VO2 at AT, and MET at AT, which indicate reduced exercise tolerance. And further multiple comparisons showed that there were no statistically significant differences between rSS = 0 and 0 < rSS ≤ 8 groups, while the aforementioned CPET variables were significantly lower in rSS > 8 group compared with rSS = 0 group. Logistic regression analysis showed that rSS was an independent risk factor for reduced exercise tolerance.