Bruce D. Nearing

EFFECTS OF CONTROLLED EXERCISE REHABILITATION ON QRS/T ANGLE IN CAD PATIENTS WITH AND WITHOUT DIABETES

methods: Diabetic (n=20) and non-diabetic patients (n=22) with angiographically proven CAD were selected from ARTEMIS exercise study, a twoyear randomized and controlled exercise trial. Patients were matched on age, sex, prior myocardial infarction and revascularization. Holter recordings (24h) were performed before and after 12-month training. Linear regression was used to calculate a predicted QRSTA at 60bpm.

Ambulatory monitoring of T-wave alternans for detection of cardiac electrical instability: scientific rationale and technical considerations

There is mounting evidence that T-wave alternans, defined as a beat-to-beat-fluctuation in T-wave area, may provide a noninvasive marker of susceptibility to ventricular tachycardia and fibrillation. Thus, we will provide a synoptic review of the scientific rationale for employing T-wave alternans as a predictor of vulnerability and we will discuss the potential suitability of this end point for use in ambulatory Holter monitoring. The following specific questions will be addressed: (1) What are the relative merits of Fast Fourier Transform and complex demodulation for alternans analysis? (2) What is the clinical and experimental evidence linking T-wave alternans to arrhythmogenesis? (3) What technical and conceptual limitations have hindered clinical use of alternans as a measure of vulnerability? (4) Are AM Holter monitors suitable for alternans detection? What are the advantages of digital Holter monitoring for T-wave alternans? and (5) What is the rationale for combined monitoring of heart rate variability and T-wave alternans?