In-Hospital Mortality in Patients With Acute ST-Elevation Myocardial Infarction With or Without Mitral Regurgitation

Abstract

Background Mitral regurgitation (MR) is a common complication in hospitalized cardiac patients with ST-segment elevation myocardial infarction (STEMI); however, the patient outcomes depend on various factors that vary across facilities and regions. There is an acute need to stratify STEMI patients by risk of in-hospital mortality. We conducted this study to compare the mortality of patients with acute STEMI with or without MR admitted to different units of the Cardiology Department at Lady Reading Hospital (LRH) in Peshawar. Methods In this prospective study, we compared the mortality rates of STEMI patients with and without MR from June 5 to October 30, 2021. All patients with different types of STEMI treated at LRH were enrolled in the study regardless of age and gender. ST-elevation was confirmed via electrocardiogram, and MR was confirmed via echocardiography. We excluded any patients with primary organic valve disease or congenital heart disease. We also collected patient demographic and clinical characteristics. We used IBM SPSS Statistics for Windows, Version 24.0 (IBM Corp., Armonk, NY) for statistical analyses. Results Our study population included 228 patients with a mean age of 62.4 ± 12.3 years. Most of the patients were men (n=140; 61.4%), and only 78 (38.6%) were women. The prevalence of MR was 29.4%. Hypertension was the most common comorbidity (63.6%), and inferior wall myocardial infarction (MI) was the most common type of MI (49.1%). Hypertension, prehospital cardiopulmonary resuscitation (CPR), and Killip class ≥ 2 were significantly associated with MR (p<.001). In-hospital mortality was 29.8%, significantly associated with MR (p=.0001). Patients who needed CPR prior to hospitalization and those with Killip class ≥ 2 were less likely to survive (p=.0001). Conclusions MR is common following MI, especially in cases of inferior wall MI. Patients with MR have a poorer prognosis than those without MR following MI, more so when combined with other comorbidities. Regarding its relation to MI complications, an assessment of the MR is necessary to make an appropriate decision for treatment.

Keywords: comorbidities; in-hospital mortality; mitral regurgitation; risk factors; st-elevation myocardial infarction.

Figure 1. Prevalence of mitral regurgitation and in-hospital mortality

MR, mitral regurgitation

Figure 2. Comparison of in-hospital mortality among patients with MR and without MR (p=.0001)

MR, mitral regurgitation