Abstract 183: In Patients Evaluated for Chest Pain or Dyspnea, Right Bundle Branch Block and/or Right Ventricular Dysfunction Are Associated With Inferior Long Term Outcomes Independent of Stress Test Results

Abstract

Background: Association between right bundle branch block (RBBB) and/or right ventricular (RV) dysfunction or dilation and outcomes in patients evaluated with stress testing are not well investigated. Methods: Records of 404 consecutive patients referred for chest pain or dyspnea evaluation with stress echocardiogram at a single tertiary care center were reviewed. In 140 patients, baseline echocardiogram included assessment of RV dimensions and function. Demographic, clinical data, and outcomes were collected. ANOVA, chi-square, and logistic regression analyses were used. Mean follow up length was 76+/-18 months. Study was approved by the IRB. Results: Demographic data and co-morbidities, including DM, CAD, HTN and PVD, were similar in patients with RBBB and/or RV dilation or dysfunction. Baseline, pre-stress RV dysfunction or dilatation were associated with an approximate fourfold increase in mortality during follow up, regardless of stress test outcome (44% vs. 11%, p=0.0052). Ischemia during stress test was also more likely in patients with RV dysfunction or dilatation (44% vs. 15%, p=0.019). In patients with RV dilatation and/or dysfunction, RBBB on baseline ECG was noted in 33% vs. 8% in patients with normal RV size and function (p = 0.0159). However, baseline RBBB was not associated with increased mortality, ability to reach THR, or ischemia during stress test. Conclusions: RV dilation and/or dysfunction pre-stress testing was associated with increased mortality and ischemia on stress testing. Observed in 1/3 of our study patients RV dilatation and/or dysfunction, RBBB was not associated with worst outcomes. Additional studies investigating utility of pre-stress echocardiogram in assessment of RV dimensions and function are warranted.