Acute impact of right ventricular infarction on early hemodynamic course after inferior myocardial infarction.

Background: Right ventricular myocardial infarction (RVMI) is the major cause of hypotension and/or shock (HpS) after acute inferior myocardial infarction (inferior AMI). It is, however, unclear how RVMI affects the acute hemodynamic course.

Methods And Results: In the present study, 153 patients with inferior AMI caused by right coronary artery occlusion were examined. Associations between in-hospital outcome and HpS before admission (preER-HpS) or HpS after admission (postER-HpS) were assessed using multivariate logistic regression analysis. Multivariate analysis was also conducted to determine a predictor for postER-HpS, including clinical findings in the emergency room as independent variables. HpS developed in 48.4% of patients with inferior AMI. Patients with RVMI more frequently had HpS than their counterparts in the first 6 h after infarction onset. RVMI was, however, not associated with preER-HpS, but was independently with postER-HpS (odds ratio (OR): 10.1; 4.0-27.7), whereas left ventricular failure was associated with preER-HpS, but not with postER-HpS. Furthermore, RVMI (OR: 9.4; 3.6-27.1) identified at presentation predicted postER-HpS.

Conclusions: Independent of concomitant left ventricular involvement, RVMI was significantly associated with postER-HpS, but not with preER-HpS. These findings highlight the importance of identifying RVMI immediately after admission in the setting of inferior AMI. (Circ J 2010; 74: 148 - 155).