Case 112

Abstract

A 57-year-old woman with ischemic cardiomyopathy and a dual-chamber St. Jude Atlas II DR V-265 ICD presented with inappropriate shocks for sinus tachycardia detected as VT (Fig. 112.1, upper panel). The ventricular electrogram morphology discriminator (MD™)1,2 was programmed ON. This discriminator diagnoses SVT and withholds VT therapy if five of eight ventricular electrograms in a sliding window have a match score of or higher 60% with the template electrogram. The stored electrogram is shown in Fig. 112.1. The real-time electrogram in sinus rhythm, shown in the lower left panel shows a morphology match score of 100% on sinus beats. The lower right panel shows a real-time electrogram recorded during rapid atrial pacing. © Springer-Verlag London Limited 2011.