Effect of Complete Revascularization in STEMI: Ischemia-Driven Rehospitalization and Cardiovascular Mortality

Abstract

Background: Patients with ST-elevation myocardial infarction (STEMI) and multivessel coronary artery disease (MVD) who undergo complete revascularization (CR) have a more favorable prognosis than those who receive incomplete revascularization (IR), as evidenced by recent randomized controlled trials. Despite the absence of a survival benefit associated with CR in these trials, positive outcomes were ascribed to combined endpoints, such as repeat revascularization, myocardial infarction, or ischemia-driven rehospitalization. In light of the significant burden that rehospitalization from STEMI imposes on healthcare systems, we examined the long-term effects of CR on ischemia-driven rehospitalization and cardiovascular (CV) mortality in STEMI patients with MVD. Methods: In our retrospective study, we included patients with STEMI and MVD who underwent successful primary percutaneous coronary intervention (PCI) at the University Medical Centre Ljubljana between 1 January 2009, and 11 April 2011. The combined endpoint was ischemia-driven rehospitalization and CV mortality, with a minimum follow-up period of six years. Results: We included 235 participants who underwent CR (N = 70) or IR (N = 165) at index hospitalization, with a median follow-up time of 7 years (interquartile range 6.0-8.2). The primary endpoint was significantly higher in the IR group than in the CR group (47.3% vs. 32.9%, log-rank p = 0.025), driven by CV mortality (23.6% vs. 12.9%, log-rank p = 0.047), as there was no difference in ischemia-driven rehospitalization rate (log-rank p = 0.206). Ischemia-driven rehospitalization did not influence CV mortality in the CR group (p = 0.49), while it significantly impacted CV mortality in the IR group (p = 0.03). After adjusting for confounders, there were no differences in CV mortality between CR and IR groups (p = 0.622). Predictors of the combined endpoint included age (p = 0.014), diabetes (p = 0.006), chronic kidney disease (CKD) (p = 0.001), cardiogenic shock at presentation (p = 0.003), chronic total occlusion (CTO) (p = 0.046), and ischemia-driven rehospitalization (p = 0.0001). Significant risk factors for the combined endpoint were cardiogenic shock at presentation (p < 0.001), stage 4 kidney failure (p = 0.001), age over 70 years (p = 0.004), female gender (p = 0.008), and residual SYNTAX I score > 5.5 (p = 0.017). Conclusions: Patients with STEMI and MVD who underwent CR had a lower combined endpoint of ischemia-driven rehospitalizations and CV mortality than IR patients, but after adjustments for confounders, the true determinants of the combined endpoint and risk factors for the combined endpoint were independent of the revascularization method.

Keywords: ST-elevation myocardial infarction; cardiovascular mortality; complete percutaneous revascularization; ischemia-driven rehospitalization; multivessel coronary artery disease.

Scheme 1

Patient flow chart [19].

Figure 1

Rehospitalization rate and primary combined endpoint occurrence of ischemia-driven rehospitalization and CV mortality. (A) Ischemia-driven rehospitalization in the CR and IR groups; (B) ischemia-driven rehospitalization and CV mortality in the CR and IR groups. Legend: CR: complete revascularization; IR: incomplete revascularization.

Figure 2

Effect of ischemia-driven rehospitalizations on CV mortality. (A) CV mortality of the CR group: comparison between subjects without ischemia-driven rehospitalization and subjects with ischemia-driven rehospitalization; (B) CV mortality of the IR group: comparison between subjects without ischemia-driven rehospitalization and subjects with ischemia-driven rehospitalization; (C) CV mortality of the IR group: comparison between subjects who had only one and subjects who needed two or more ischemia-driven rehospitalizations. Legend: CR: complete revascularization; IR: incomplete revascularization.

Figure 3

Risk factors for ischemia-driven rehospitalization and CV mortality. LDL—low-density lipoprotein, MI before—myocardial infarction before index hospitalization, PCI before—percutaneous coronary intervention before index hospitalization, CABG before—coronary artery bypass graft surgery before index hospitalization, CTO—chronic total occlusion, R. SYNTAX—residual SYNTAX I score, IR—incomplete revascularization, St. 4 kidney f.—stage 4 or 5 kidney failure, HR—hazard ratio, CI—confidence interval.