Noninvasive Arrhythmia Risk Stratification in Idiopathic Dilated Cardiomyopathy: Design and First Results of the Marburg Cardiomyopathy Study

• Published in: Pacing and clinical electrophysiology 1998-11, Vol.21 (11), p.2551-2556
• Main Authors: GRIMM, WOLFRAM, GLAVERIS, CHRISTINA, HOFFMANN, JÜRGEN, MENZ, VOLKER, MET, NADJA, BORN, STEPHAN, MAISCH, BERNHARD
• Format: Article
• Language: English
• Subjects: arrhythmia risk prediction; Arrhythmias, Cardiac - epidemiology; Cardiomyopathy, Dilated - complications; Cardiomyopathy, Dilated - epidemiology; Death, Sudden, Cardiac - prevention & control; Defibrillators, Implantable; dilated Cardiomyopathy; Electrocardiography - methods; Electrocardiography, Ambulatory - methods; Female; Follow-Up Studies; Humans; Male; Middle Aged; Prognosis; Prospective Studies; Research Design; Risk Assessment; Signal Processing, Computer-Assisted; sudden death; Time Factors
• ISSN: 0147-8389; 1540-8159
• DOI: 10.1111/j.1540-8159.1998.tb01217.x

The Marburg Cardiomyopathy Study (MACAS) is a prospective, observational study designed to determine the value of the following potential noninvasive arrhythmia risk predictors in at least 200 patients with idiopathic dilated Cardiomyopathy (IDC) over a 5‐year follow‐up period: NYHA‐class, left ventricular ejection fraction (LVEF), left ventricular end‐diastolic diameter, left bundle branch block and atrial fibrillation on ECG, QT/JT dispersion on 12‐lead ECG, signal‐averaged ECG, ventricular arrhythmias and heart rate variability (HRV) on 24‐hour Hotter ECG, baroreflex sensitivity, and microvolt T wave alternans during exercise. This article describes the findings among the first 159 patients with IDCs enrolled in MACAS until May 1998 (40 women, 119 men;age:49 ± 12 years; LVEF: 32 ± 10%). Twenty‐nine patients (18%) had atrial fibrillation and 130 patients (82%) were in sinus rhythm. Patients with sinus rhythm were further stratified according to LVEF < 30% (n = 54) versus LVEF ≥ 50% (n = 76). Compared to patients with LVEF ≥ 30%, patients with LVEF < 30% more often had left bundle branch block (43% vs 25%, P < 0.05), nonsustained VT (44% vs 22%, P < 0.05), decreased HRV (SDNN: 95 ± 39 vs 128 ± 42 ms, P < 0.01), decreased baroreflex sensitivity (5.6 ± 4 vs 8.3 ± 6 ms/mmHg, P < 0.01), and T wave alternans (59% vs 37%, P < 0.05). The prognostic significance of these findings will be determined by multivariate Cox analysis at the end of a 5‐year follow‐up. Primary endpoints in MACAS are overall mortality and arrhythmic events (i.e., sustained VT or VF, or sudden cardiac death).