Patterns of Coronary Compromise Resulting in Acute Right Ventricular Ischemic Dysfunction

Abstract

Background-Although proximal right coronary artery (RCA) occlusion is the culprit commonly responsible for acute right ventricular (RV) infarction (RVI), the severity of RV dysfunction ranges broadly. This study was designed to delineate the patterns of coronary compromise that determine the magnitude of RV ischemic dysfunction. Methods and Results-In 125 patients with acute inferior myocardial infarction undergoing emergency angiography, the culprit infarct lesion was identified, RV branch flow assessed (TIMI flows and frame counts), and individual patient RV perfusion indices calculated by separately averaging the branch flows and frame counts, which were correlated with RV wall motion by ultrasound. RVI occurred in 53 (42%) patients, with the RCA as the culprit vessel and the lesion sufficiently proximal to compromise flow in at least one RV branch in all cases, thereby resulting in depressed RV perfusion (flow index, 0.7Ϯ0.2). In patients without RVI, the RCA was the culprit in 89%; the circumflex, in 11%. RCA culprits were proximal in 19% of such cases, with lack of RVI explained by preserved RV perfusion (flow index, 2.7Ϯ0.3; Pϭ0.001) attributable to at least 1 patent RV branch, spontaneous reperfusion, or prominent collaterals.Overall, there was a strong correlation between RV perfusion and wall motion (Spearman correlation coefficientϭ0.79). Conclusions-Proximal RCA occlusion compromising RV branch perfusion commonly results in RV ischemic dysfunction. In some cases with proximal RCA culprits, collaterals or spontaneous reperfusion preserve RV performance.

The change in right ventricular systolic function according to the revascularisation method used, following acute ST -segment elevation myocardial infarction

“…The involvement of the RV during inferior acute MI has been defined as a strong predictor of morbidity and in-hospital mortality 7,8. Previous studies described proximal RCA occlusion compromising flow to the major RV branches as the most common anatomical substrate for RV dysfunction 34-36. However our study confirmed that the location of the proximal RCA lesion was similar between the study groups.…”

Acute myocardial infarction with ST segment elevation in inferior and anterior leads: right ventricular infarction

“…In some cases with proximal RCA culprits, collaterals or spontaneous reperfusion preserve right ventricular performance 21. Acute MI with simultaneous ST segment elevation in the precordial and inferior leads can also be caused by a wrapped LAD, defined as an LAD extending around the apex to supply part of the inferior wall of the left ventricle.…”

Right ventricular myocardial infarction: pathophysiology, diagnosis, and management

“…RVMI occurs principally due to occlusion of the RCA proximal to the major RV branches in the context of an inferior MI 26. It may also occur by occlusion of the left circumflex artery in patients with a left-dominant circulation but also, less commonly, in anterior infarcts as the anterior part of the RV free wall is supplied by collaterals from the left anterior descending artery 18.…”