title: Right ventricular dysfunction predisposes to inducible ventricular tachycardia at electrophysiology studies in patients with acute ST-segment-elevation myocardial infarction and reduced left ventricular ejection fraction.
abstract: BACKGROUND
  Inducible ventricular tachycardia (VT) is a strong predictor of spontaneous ventricular tachyarrhythmia following ST-segment-elevation myocardial infarction. Reduced left ventricular ejection fraction (EF) predisposes patients to inducible VT after ST-segment-elevation myocardial infarction. However, the role of right ventricular (RV) dysfunction in predisposing to inducible VT has not been described previously.
  
  
  RESULTS
  Consecutive patients with ST-segment-elevation myocardial infarction treated with primary percutaneous coronary intervention underwent predischarge radionuclide gated heart pool scan to assess ventricular EF. The study cohort included patients with reduced left ventricular EF (left ventricular EF ≤40%) who underwent electrophysiology study (n=220) in an attempt to induce VT. We defined RV dysfunction as RVEF ≤35%. The end point was sustained monomorphic VT (cycle length ≥200 ms). This was considered a positive study. No inducible arrhythmia, ventricular fibrillation, or flutter (cycle length <200 ms) was considered a negative study. Infarct region, infarct-related artery, male sex, 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 electrophysiology study (P<0.001; odds ratio, 5.8; 95% confidence interval, 3.005-11.262).
  
  
  CONCLUSIONS
  RV dysfunction (RVEF ≤35%) predisposed to inducible VT at electrophysiology study in patients with impaired left ventricular EF (≤40%) after acute ST-segment-elevation myocardial infarction treated with primary percutaneous coronary intervention.
authors.affiliation: From the Westmead Hospital, Westmead, Australia (J.B.T., S.Z., K.B., A.N., A.T., C.C., S.P.T., G.S., D.F., R.B., P.K.) and Sydney Medical School, University of Sydney, Sydney, Australia (J.B.T., A.T., C.C., S.P.T., G.S., P.K.).
authors.forename: Jay B
authors.initials: JB
authors.lastname: Thakkar
authors.affiliation: From the Westmead Hospital, Westmead, Australia (J.B.T., S.Z., K.B., A.N., A.T., C.C., S.P.T., G.S., D.F., R.B., P.K.) and Sydney Medical School, University of Sydney, Sydney, Australia (J.B.T., A.T., C.C., S.P.T., G.S., P.K.).
authors.forename: Sarah
authors.initials: S
authors.lastname: Zaman
authors.affiliation: From the Westmead Hospital, Westmead, Australia (J.B.T., S.Z., K.B., A.N., A.T., C.C., S.P.T., G.S., D.F., R.B., P.K.) and Sydney Medical School, University of Sydney, Sydney, Australia (J.B.T., A.T., C.C., S.P.T., G.S., P.K.).
authors.forename: Karen
authors.initials: K
authors.lastname: Byth
authors.affiliation: From the Westmead Hospital, Westmead, Australia (J.B.T., S.Z., K.B., A.N., A.T., C.C., S.P.T., G.S., D.F., R.B., P.K.) and Sydney Medical School, University of Sydney, Sydney, Australia (J.B.T., A.T., C.C., S.P.T., G.S., P.K.).
authors.forename: Arun
authors.initials: A
authors.lastname: Narayan
authors.affiliation: From the Westmead Hospital, Westmead, Australia (J.B.T., S.Z., K.B., A.N., A.T., C.C., S.P.T., G.S., D.F., R.B., P.K.) and Sydney Medical School, University of Sydney, Sydney, Australia (J.B.T., A.T., C.C., S.P.T., G.S., P.K.).
authors.forename: Aravinda
authors.initials: A
authors.lastname: Thiagalingam
authors.affiliation: From the Westmead Hospital, Westmead, Australia (J.B.T., S.Z., K.B., A.N., A.T., C.C., S.P.T., G.S., D.F., R.B., P.K.) and Sydney Medical School, University of Sydney, Sydney, Australia (J.B.T., A.T., C.C., S.P.T., G.S., P.K.).
authors.forename: Clara
authors.initials: C
authors.lastname: Chow
authors.affiliation: From the Westmead Hospital, Westmead, Australia (J.B.T., S.Z., K.B., A.N., A.T., C.C., S.P.T., G.S., D.F., R.B., P.K.) and Sydney Medical School, University of Sydney, Sydney, Australia (J.B.T., A.T., C.C., S.P.T., G.S., P.K.).
authors.forename: Stuart P
authors.initials: SP
authors.lastname: Thomas
authors.affiliation: From the Westmead Hospital, Westmead, Australia (J.B.T., S.Z., K.B., A.N., A.T., C.C., S.P.T., G.S., D.F., R.B., P.K.) and Sydney Medical School, University of Sydney, Sydney, Australia (J.B.T., A.T., C.C., S.P.T., G.S., P.K.).
authors.forename: Gopal
authors.initials: G
authors.lastname: Sivagangabalan
authors.affiliation: From the Westmead Hospital, Westmead, Australia (J.B.T., S.Z., K.B., A.N., A.T., C.C., S.P.T., G.S., D.F., R.B., P.K.) and Sydney Medical School, University of Sydney, Sydney, Australia (J.B.T., A.T., C.C., S.P.T., G.S., P.K.).
authors.forename: David
authors.initials: D
authors.lastname: Farlow
authors.affiliation: From the Westmead Hospital, Westmead, Australia (J.B.T., S.Z., K.B., A.N., A.T., C.C., S.P.T., G.S., D.F., R.B., P.K.) and Sydney Medical School, University of Sydney, Sydney, Australia (J.B.T., A.T., C.C., S.P.T., G.S., P.K.).
authors.forename: Robert
authors.initials: R
authors.lastname: Barnett
authors.affiliation: From the Westmead Hospital, Westmead, Australia (J.B.T., S.Z., K.B., A.N., A.T., C.C., S.P.T., G.S., D.F., R.B., P.K.) and Sydney Medical School, University of Sydney, Sydney, Australia (J.B.T., A.T., C.C., S.P.T., G.S., P.K.). pramesh.kovoor@sydney.edu.au.
authors.forename: Pramesh
authors.initials: P
authors.lastname: Kovoor
mesh_terms: D000368:Aged; D002304:Cardiac Pacing, Artificial; D016009:Chi-Square Distribution; D022062:Electrophysiologic Techniques, Cardiac; D005260:Female; D006801:Humans; D016015:Logistic Models; D008297:Male; D008875:Middle Aged; D015999:Multivariate Analysis; D009203:Myocardial Infarction / Q000150:complications* / Q000175:diagnosis / Q000503:physiopathology / Q000628:therapy; D062645:Percutaneous Coronary Intervention; D011237:Predictive Value of Tests; D011446:Prospective Studies; D015635:Radionuclide Ventriculography; D012307:Risk Factors; D013318:Stroke Volume; D017180:Tachycardia, Ventricular / Q000175:diagnosis / Q000209:etiology* / Q000503:physiopathology; D018487:Ventricular Dysfunction, Left / Q000175:diagnosis / Q000209:etiology* / Q000503:physiopathology; D018497:Ventricular Dysfunction, Right / Q000175:diagnosis / Q000209:etiology* / Q000503:physiopathology; D016277:Ventricular Function, Left; D016278:Ventricular Function, Right
keywords: electrophysiology; heart ventricles; myocardial infarction; stroke volume; tachycardia, ventricular