Right Ventricular Dysfunction Predisposes to Inducible Ventricular Tachycardia at Electrophysiology Studies in Patients with Acute ST Elevation Myocardial Infarction and Reduced Left Ventricle Ejection Fraction
Background—Inducible Ventricular tachycardia (VT) is a strong predictor of spontaneous ventricular tachyarrhythmia following ST elevation myocardial infarction (STEMI). Reduced left ventricular ejection fraction (LVEF) predisposes patients to inducible ventricular tachycardia post STEMI. However the role of right ventricular (RV) dysfunction in predisposing to inducible VT has not been described previously.
Methods and Results—Consecutive patients with STEMI treated with primary percutaneous coronary intervention (PPCI) underwent pre-discharge radionuclide gated heart pool scan (GHPS) to assess ventricular ejection fraction (EF). The study cohort included patients with reduced LVEF (LVEF ≤40%), that underwent electrophysiology study (EPS) (n=220) in an attempt to induce VT. We defined RV dysfunction as right ventricular ejection fraction (RVEF) ≤35%. The end point was sustained monomorphic VT (Cycle length CL ≥200ms). This was considered a positive study. No inducible arrhythmia, ventricular fibrillation or flutter (CL<200ms) was considered a negative study. Infarct region, infarct related artery, male gender and RVEF ≤35%, were univariable predictors of positive test. After multivariable analysis, RVEF ≤35% had the strongest association as an independent predictor of inducible VT at EPS (p<0.001, OR 5.8; 95% CI, 3.005 to 11.262).
Conclusions—RV dysfunction (RVEF ≤35%) predisposed to inducible VT at EPS in patients with impaired LVEF (≤ 40%) after acute STEMI treated with primary PCI.
- Received December 10, 2013.
- Revision received June 19, 2014.
- Accepted June 23, 2014.