A STUDY ON THE IMPACT OF RIGHT VENTRICULAR INVOLVEMENT ON MORTALITY AND MORBIDITY IN PATIENTS WITH INFERIOR WALL MYOCARDIAL INFARCTION

*Dr. Akash B. J., Dr. Arun M. and Dr. Mary Priya Varghese

ABSTRACT

Introduction: Inferior wall myocardial infarction (IWMI), caused by coronary artery occlusion, accounts for 40%-50% of myocardial infarctions(MIs), often involving the posterior descending branch of the right coronary artery. While IWMI generally has a better prognosis than anterior MIs, right ventricular myocardial infarction (RVMI) significantly worsens outcomes. RVMI, occurring in 20%-50% of IWMI cases, can lead to complications like hypotension, bradycardia, shock, and AV block, independent of left ventricular function. RV involvement is associated with higher morbidity and mortality. Recognizing RVMI as a distinct clinical entity is crucial for effective management and improved outcomes.
Objective
1) To evaluate the impact of right ventricular (RV) myocardial involvement on mortality and morbidity in patients with inferior myocardial infarction (MI).
Materials and methods: A hospital-based, prospective observational study was conducted on 150 patients diagnosed with acute inferior wall myocardial infarction (MI). Coronary risk factors such as diabetes mellitus, hypertension, smoking, obesity, alcohol use, and dyslipidemia were also assessed. Twelve-lead ECG, cardiac enzyme assay and echocardiography were undertaken in all the participants. Data collection involved a structured proforma and a comprehensive physical examination focusing on hemodynamic parameters, including jugular venous pulse (JVP) and blood pressure. Statistical analysis was done by using SPSS Statistical Analysis software version 23. Results: Among the 150 patients studied, 45 (30%) were diagnosed with right ventricular myocardial infarction (RVMI). Complications were notably less frequent in patients with isolated inferior wall myocardial infarction (IWMI) compared to those with IWMI and associated RVMI, except for pulmonary edema, where the difference was statistically significant (p<0.05). Of the 22 deaths recorded (14.67%), 18 (12%) occurred in patients with RVMI, while only 4 (2.66%) were in those with isolated IWMI, a difference that was also statistically significant. Conclusion: Right ventricular involvement in inferior wall myocardial infarction (IWMI) significantly increases complications and mortality rates. Right ventricular myocardial infarction (RVMI) leads to severe hemodynamic instability, increasing risks of hypotension, shock, arrhythmias, cardiac arrest, and heart failure. Early detection of RVMI is essential for timely management.

Keywords: Inferior wall myocardial infarction; Right ventricular myocardial infarction; Myocardial infarction; Mortality; Right ventricular.