Right and Left Ventricular Dysfunction in Inferior Acute Myocardial Infarction

Abstract

We studied by equilibrium radionuclide angiography 100 patients with a first inferior acute myocardial infarction between the 2nd and the 4th day of the onset of symptoms. The aim of our work was to correlate right and left ventricular dysfunction (depressed ejection fraction associated with regional wall motion abnormalities) with the prevalence of each major in-hospital complication and to identify the major complications which most frequently occur in association with the others. Right ventricular dysfunction (RVD) was diagnosed in 47% of our patient population; their mean left ventricular ejection fraction (LVEF) was still in the normal range, but significantly (p < 0.05) lower than that of the group without RVD. Left ventricular dysfunction (LVD) was detected in only 34% of our patients. Patients who developed major complications (68%) had a depressed right ventricular ejection fraction, significantly lower than that of uncomplicated patients (p < 0.02) in the absence of significant abnormalities of LVEF. RVD was diagnosed in all 12 patients who developed cardiogenic and/or hypovolaemic shock: this correlation was highly significant; LVD was identified in only 3 of them. Of the 16 patients who developed congestive heart failure (CHF), 14 showed RVD: this correlation was also highly significant. LVD was detected in 8 of 16 patients who experienced CHF, but this correlation was not statistically significant. Advanced atrioventricular block complicated the course of 21 patients: RVD and LVD were found in 67 and 28% of them, respectively. Bradycardia and hypotension, major ventricular arrhythmias, extension of infarction, postinfarction angina, and death showed no significant correlation with either LVD or RVD. Both patients who had an advanced atrioventricular block and those who experienced CHF showed a significantly (p < 0.002) higher prevalence of multiple complications. We conclude that, in patients with inferior acute myocardial infarction, RVD is significantly correlated with cardiogenic and/or hypovolaemic shock and CHF in spite of a generally preserved LVEF. Both in patients with advanced atrioventricular block and in those with CHF, multiple complications are significantly more frequent.