Filtered QRS Duration on Signal-Averaged Electrocardiography Predicts Inducibility of Ventricular Tachycardia in Arrhythmogenic Right Ventricle Dysplasia
ABSTRACT Treatment of arrhythmogenic right ventricular dysplasia (ARVD) is mostly based on the prevention of sudden cardiac death that results from arrhythmias. A clinical history suggestive of ARVD requires careful evaluation including electrophysiological study. The potential ability to identify those patients who will have inducible VT with electrophysiological study will enable better risk stratification and selection of vulnerable patients for electrophysiologically guided therapy. The purpose of the study was to evaluate the predictive ability of signal-averaged electrocardiography (SAECG) to predict inducibility of VT in patients with ARVD. The patient population consisted of 31 ARVD patients diagnosed with McKenna's criteria who underwent electrophysiological study. Electrophysiological study was considered positive if sustained monomorphic VT was induced. The sensitivity, specificity, and predictive accuracy of various SAECG criteria for inducibility of sustained monomorphic VT were also calculated. Twenty-one patients had inducible VT. The filtered QRS duration (fQRS), duration of signal <40 uV (LAS40), and root mean square voltage in the last 40 ms of QRS duration (RMS40) in ARVD patients induced versus noninduced were 122 +/- 21 and 103 +/- 8 ms (P=0.007), 45 +/- 20 and 28 +/- 14 ms (P=0.02), 19 +/- 19 and 32 +/- 22 uV (0.03), respectively. The ejection fractions were comparable in both groups. fQRS duration > or =110 ms had sensitivity of 91%, specificity of 90%, and a total predictive accuracy of 90% in predicting inducibility of VT in these patients. Filtered QRS duration on SAECG is predictive of electrophysiological study outcome in ARVD. Further studies will be needed to determine if SAECG results can predict the development of ventricular arrhythmias during follow-up.
- [Show abstract] [Hide abstract]
ABSTRACT: Arrhythmogenic right ventricular dysplasia/cardiomyopathy (ARVD/C) is a genetic cardiomyopathy characterized by ventricular arrhythmias and structural abnormalities of the right ventricle (RV). In ARVD/C there is progressive replacement of right ventricular myocardium with fatty and fibrous tissue. The precise prevalence of ARVD/C has been estimated to vary between 1 in 1000 and 1 in 5000 of the general population. The purpose of this chapter is to review the current understanding of ARVD/C and its management. Particular attention will be focused on some of the recent advances in the understanding of the genetic basis of ARVD/C and how this information provides insight into the mechanism of ventricular arrhythmias that can cause sudden death.
- Der Pathologe 06/1992; 13(3):141-5. · 0.64 Impact Factor
Conference Paper: High power battery tester development[Show abstract] [Hide abstract]
ABSTRACT: This paper describes the development of novel test equipment for evaluating high-power batteries under multi-kW load requirements. Two testers were designed, fabricated, and placed in service during this effort. One was an air-cooled system (16 kW power capacity) and the other a water-cooled system (36 kW power capacity). Both testers used National Instruments LabView real-time software and hardware running on a Windows PC using the Windows 98 operating system to control tests and acquire data. The test capability was established to support battery development and evaluation work proceeding in parallel with these activities. This paper will review the challenges encountered and the solutions developed during the project.Power Modulator Symposium, 2002 and 2002 High-Voltage Workshop. Conference Record of the Twenty-Fifth International; 01/2002