BACKGROUND: Monitoring arrhythmic risk may improve management of @entity1 with @entity737 ( @entity737 ) and prevent @entity1457 . Changes in repolarization duration between subsequent beats quantified as short-term variability (STV) is associated with @entity943 in several animal models. OBJECTIVE: We evaluated STV of QT from right ventricular intracardiac @entity737 electrograms in @entity1 with structural @entity299 and compared its predictive value with the QT variability index (QTVI). METHODS: In 233 @entity1 , STV over 60 beats for QT and RR intervals and their ratio was calculated (STV(QT), @entity23888 (RR), STV(Ratio), respectively). QTVI was derived from mean and SD of QT and heart rate. Follow-up duration was 26    15 months. Predictive value was determined for @entity944 ( @entity944 ) defined as @entity1164 or fast @entity1165 /fibrillation [CL < 240 ms]. RESULTS: In univariate analysis, STV(Ratio), but not STV(QT) or STV(RR), was predictive of @entity944 . Hazard ratios for highest quartile STV(Ratio) and QTVI were comparable (STV(Ratio): 1.9, 95% confidence interval [CI] 1.1 to 3.3, P = .038, QTVI: 2.2, 95% CI 1.2 to 3.8, P = .010). In a multivariate model, highest quartile STV(Ratio) was predictive of @entity944 after adjustment for New York Heart Association class, history of @entity63 , @entity737 indication, and use of class I antiarrhythmics (hazard ratio 1.8, 95% CI 1.0 to 3.4, P < .050). A combined criterion of highest quartile for both STV(Ratio) and QTVI identified @entity1 at highest risk (hazard ratio 2.4, 95% CI 1.3 to 4.3, P = .005, positive predictive value 38%, negative predictive value 82%). CONCLUSION: STV(Ratio) from @entity737 electrograms is predictive of @entity944 . Predictive value is similar for order-based STV(Ratio) and distribution-based QTVI, but the combination of both parameters can further improve results.

Short-term variability of repolarization predicts XXXX and @entity1164 in @entity1 with structural @entity299 : a comparison with QT variability index.

@entity1 :: ('9606', 'Species') :: ['patients'] @entity1164 :: ('MESH:D016757', 'Disease') :: ['sudden cardiac death'] @entity1165 :: ('MESH:D017180', 'Disease') :: ['ventricular tachycardia'] @entity944 :: ('MESH:D003645', 'Disease') :: ['SAD', 'sudden arrhythmic death'] @entity63 :: ('MESH:D007511', 'Disease') :: ['ischemia'] @entity1457 :: ('MESH:D012769', 'Disease') :: ['ICD shocks'] @entity737 :: ('MESH:D057873', 'Disease') :: ['implantable cardioverter-defibrillators', 'ICD'] @entity299 :: ('MESH:D006331', 'Disease') :: ['heart disease'] @entity23888 :: ('CHEBI:63581', 'Chemical') :: ['STV'] @entity943 :: ('MESH:D001145', 'Disease') :: ['ventricular arrhythmias']
@entity1165 :: (MESH:D017180,Disease) :: ['ventricular tachycardia']
