Enhanced Detection of Arrhythmia Vulnerability Using T Wave Alternans, Left Ventricular Ejection Fraction, and Programmed Ventricular Stimulation:

Abstract

The combined use of TWA, LVEF, and PVS is a promising new approach to arrhythmia risk stratification that permits identification of high-risk and very-low-risk patients.

Is T-wave alternans as good or better than programmed ventricular stimulation?

“…Although surprising, this near-equivalence of PVS and TWA was recently presented in the Alternans Before Cardioverter Defibrillator (ABCD) study (18), of 566 MUSTT-type patients with LVEF 28±7 % (table). In both studies, the NPV of TWA was similar to those of PVS in MUSTT (table), and in ABCD the 1-year NPV improved to 98 % if TWA and PVS were combined (18,19). This range of NPV is actually similar to earlier studies.…”

Is Microvolt T-Wave Alternans the Answer to Risk Stratification in Heart Failure?

“…The first study performed MTWA testing in 144 nonconsecutive patients referred for EPS. 23 The cohort was divided into primary (nϭ88) and secondary (nϭ56) prevention subgroups, and 111 patients received an ICD. A positive MTWA test did not predict the primary end point (death/ VTE) in the primary prevention subgroup.…”

The Photodiode Array: A Critical Cornerstone in Cardiac Optical Mapping

“…For example, a one-to-one APD alternans occurs when a normal AP is followed by a short-duration AP, which is then followed by normal AP, short-duration AP, and so on. Electrical alternans are considered to be a strong marker of electrical instability, and often precede malignant arrhythmias such as ventricular tachycardia (VT) and VF (Hohnsloser et al, 1998;Gold et al, 2000;Ikeda et al, 2006;Pastore et al, 1999;Pham et al, 2003;Rashba et al, 2004;Rosenbaum et al, 1994). In this s tudy by Lak ireddy et al , i schemia-induced changes in APD and intracellular calcium transient duration (Ca i T-D) were determined, and their relationship with electrical alternans was investigated.…”