This Article Figures Only Full Text Full Text (PDF) All Versions of this Article: j.jacc.2007.02.071v1 50/3/225    most recent Alert me when this article is cited Alert me if a correction is posted Services Email this article to a friend Similar articles in this journal Similar articles in Web of Science Alert me to new issues of the journal Download to citation manager Citing Articles Citing Articles via HighWire Citing Articles via Web of Science (5) Citing Articles via Google Scholar Google Scholar Articles by Iacoviello, M. Articles by Pitzalis, M. Search for Related Content PubMed Articles by Iacoviello, M. Articles by Pitzalis, M. Related Collections Related Article

CLINICAL RESEARCH: HEART RHYTHM DISORDER

Ventricular Repolarization Dynamicity Provides Independent Prognostic Information Toward Major Arrhythmic Events in Patients With Idiopathic Dilated Cardiomyopathy

Massimo Iacoviello, MD, PhD^_*,_*, Cinzia Forleo, MD, PhD^_*, Pietro Guida, PhD^_*, Roberta Romito, MD, Antonio Sorgente, MD^_*, Sandro Sorrentino, PhD^_*, Silvana Catucci, MD^_*, Filippo Mastropasqua, MD and Mariavittoria Pitzalis, MD, PhD

^_* Institute of Cardiology, University of Bari, Bari, Italy
Emergency Cardiology Department, University-Hospital of Bari, Bari, Italy
Division of Cardiology, "S. Maugeri" Foundation, Cassano delle Murge, Italy
Division of Cardiology, Department of Internal Medicine, The Brody School of Medicine at East Carolina University, Greenville, North Carolina.

Manuscript received December 1, 2006; revised manuscript received February 6, 2007, accepted February 12, 2007.

^_* Reprint requests and correspondence: Dr. Massimo Iacoviello, Institute of Cardiology, University of Bari, Piazza Giulio Cesare 11, 70124 Bari, Italy. (Email: massimo.iacoviello{at}cardio.uniba.it).

Objectives: The purpose of this work was to evaluate whether ventricular repolarization dynamicity predicts major arrhythmic events in patients with idiopathic dilated cardiomyopathy (DCM).

Background: Arrhythmic risk stratification in patients with DCM is still an open issue. Ventricular repolarization analysis should provide relevant information, but QT interval and QT dispersion failed in predicting arrhythmic risk.

Methods: The following parameters were evaluated in 179 consecutive DCM patients without history of sustained ventricular tachycardia (VT) and/or ventricular fibrillation (VF) at enrollment: QRS duration, QT interval corrected for heart rate, and QT dispersion at electrocardiogram (ECG); left ventricular ejection fraction (LVEF) and left ventricular end-diastolic diameter at echocardiogram; and nonsustained ventricular tachycardia (NSVT), heart rate variability (standard deviation of RR intervals), and ventricular repolarization dynamicity as measured by means of 24-h ECG monitoring, by calculating the slope of linear regression analysis of QT end and RR intervals (QTe-slope) and the value of mean QT end corrected for heart rate.

Results: During a mean follow-up of 39 months, 9 patients died suddenly and 15 experienced VT and/or VF. At multivariate analysis, LVEF (p = 0.047), NSVT (p = 0.022), and QTe-slope (p = 0.034) were significantly associated with arrhythmic events. Among the patients with a low LVEF, NSVT and/or steeper QTe-slope identified a subgroup at highest arrhythmic risk.

Conclusions: In patients with DCM, QT dynamicity is independently associated with the occurrence of major arrhythmic events and improves the predictive accuracy of stratifying arrhythmic risk of these patients.

Abbreviations and Acronyms   DCM = dilated cardiomyopathy   ICD = implantable cardioverter-defibrillator   LVEDD = left ventricular end-diastolic diameter   LVEF = left ventricular ejection fraction   NSVT = nonsustained ventricular tachycardia   QTa = QT apex   QTd = QT dispersion   QTe = QT end   QTe-slope = slope of linear regression analysis of QT end and RR intervals   SDNN = standard deviation of normal RR intervals   VF = ventricular fibrillation   VT = ventricular tachycardia

Related Article

Holter Electrocardiogram Parameters in Risk Stratification of Arrhythmic Events in Idiopathic Dilated Cardiomyopathy: More Studies Are Needed

Wojciech Zareba
J. Am. Coll. Cardiol. 2007 50: 232-233. [Full Text] [PDF]

This article has been cited by other articles:

				M. R. de Sousa, C. A. Morillo, F. T. Rabelo, A. M. N. Filho, and A. L.P. Ribeiro Non-sustained ventricular tachycardia as a predictor of sudden cardiac death in patients with left ventricular dysfunction: A meta-analysis Eur J Heart Fail, October 1, 2008; 10(10): 1007 - 1014. [Abstract] [Full Text] [PDF]

				L. Ding, W. Hua, H. Niu, K. Chen, and S. Zhang Primary prevention of sudden cardiac death using implantable cardioverter defibrillators Europace, September 1, 2008; 10(9): 1034 - 1041. [Abstract] [Full Text] [PDF]

				A. N. DeMaria, J. J. Bax, O. Ben-Yehuda, P. Clopton, G. K. Feld, G. S. Ginsburg, B. H. Greenberg, J. D. Knoke, W. Y.W. Lew, J. A.C. Lima, et al. Highlights of the year in JACC 2007. J. Am. Coll. Cardiol., January 29, 2008; 51(4): 490 - 512. [Full Text] [PDF]

				W. Zareba Holter Electrocardiogram Parameters in Risk Stratification of Arrhythmic Events in Idiopathic Dilated Cardiomyopathy: More Studies Are Needed J. Am. Coll. Cardiol., July 17, 2007; 50(3): 232 - 233. [Full Text] [PDF]