Long-Term Outcomes in Acute Inferior Myocardial Infarction Patients with Right Ventricular Myocardial Infarction

Abstract

Objective: To evaluate the prognostic influence of the presence of right ventricular myocardial infarction (RVMI) on patients with acute inferior myocardial infarction (MI) in the contemporary reperfusion era.

Methods: A total of 9,308 patients with acute inferior MI were included from the prospective, nationwide, multicenter China Acute Myocardial Infarction Registry, including 1,745 (18.75%) patients with RVMI and 7,563 (81.25%) patients without RVMI. The primary outcome was all-cause mortality. The secondary outcome was major adverse cardiac and cerebrovascular event (MACCE) defined as a composite of all-cause mortality, recurrent MI, revascularization, stroke, and major bleeding.

Results: There were no significant differences between acute inferior MI patients with or without RVMI in all-cause mortality and MACCE. Acute inferior MI patients with RVMI was associated with higher risks of in-hospital atrial-ventricular block (5.8% vs 3.1%; adjusted OR: 1.39; 95% CI: 1.06 to 1.84; P=0.0187) and two-year revascularization (10.3% vs 8.1%; adjusted HR: 1.21; 95% CI: 1.01 to 1.45; P=0.0418) relative to patients without RVMI. Primary percutaneous coronary intervention (PCI) and thrombolysis were all independent predictors to decrease both in-hospital and two-year all-cause mortality. For patients who received timely reperfusion, RVMI involvement did not increase all-cause mortality, whereas for those who did not undergo reperfusion treatment, RVMI involvement significantly increased all-cause mortality (20.3% vs 15.7%; HR: 1.34; 95% CI: 1.10 to 1.63).

Conclusion: RVMI involvement did not increase all-cause mortality for acute inferior MI patients in contemporary reperfusion era, whereas the risk of all-cause mortality was increased for patients with no reperfusion treatment.

Note: Funding: This work was supported by the CAMS Innovation Fund for Medical Sciences（CIFMS） (2016-I2M-1-009) and the Twelfth Five-Year Planning Project of the Scientific and Technological Department of China (2011BAI11B02).

Declaration of Interests: All authors declared no conflicts of interest.

Ethics Approval Statement: This study was approved by the institutional review board of all participating hospitals. Written informed consent was obtained from eligible patients before registration, and the study protocol conforms to the ethical guidelines of the 1975 Declaration of Helsinki.

Trial Registration: This study was registered on ClinicalTrials.gov (NCT01874691).

Keywords: right ventricular myocardial infarction, acute inferior myocardial infarction, percutaneous coronary intervention, thrombolysis, all-cause mortality