Abstract 11497: Determinants of Changes in Right Ventricular Dimensions and Function Following ST-Segment Elevation Myocardial Infarction

Abstract

Introduction: RV function is an important prognostic marker of morbidity and mortality in STEMI patients. However, little is known of the time course of RV function and dimensions, the inter-ventricular interaction with the LV and the predictors of reduced RV function during follow-up after STEMI.

Hypothesis: The aim of this study was to evaluate the pattern of RV dimensions and function over time and to assess the echocardiographic determinants of changes in RV function and dimensions.

Methods: First STEMI patients treated with primary PCI were included (n=496; mean age 60 ± 11 years; 78% male; 50% LAD, 35% RCA and 15% CX as culprit vessel; mean baseline LVEF 46 ± 8%). RV and LV echocardiographic parameters were assessed at baseline, 6 months and 12 months post-infarction.

Results: RV function, measured by TAPSE, increased significantly over time (baseline: 18.7 ± 0.2, 6 months: 20.2 ± 0.2, 12 months: 20.0 ± 0.2, P <0.001) and was accompanied by a modest but significant increase in RV end-diastolic area (RVEDA) (baseline: 17.6 ± 0.2, 6 months: 18.3 ± 0.2, 12 months: 18.1 ± 0.2, P <0.001, Figure). Change in TAPSE was independently associated with changes in wall motion score index (WMSI), mitral regurgitation grade, RVEDA and right atrial (RA) area (P for all parameters <0.003). In an additional analysis, changes in LV end-diastolic volume, WMSI, TAPSE and RA area were independently related with change in RVEDA (P for all parameters <0.01). Finally, after adjustment for clinical and echocardiographic parameters, independent baseline predictors of 6-month TAPSE ≤15 mm were multivessel disease, LVEF and TAPSE.

Conclusions: Despite progressive RV remodeling, RV function improves during 12 months follow-up after STEMI. This improvement is related to changes in LV function and dimensions. Furthermore, RV dysfunction during follow-up is significantly associated with LV dysfunction. Assessment of both LV and RV may improve the clinical management of STEMI patients during follow-up.