Clinical Predictors of Transvenous Defibrillation Energy Requirements

• Published in: The American journal of cardiology 1997-01, Vol.79 (2), p.150-153
• Main Authors: Khalighi, Koroush, Daly, Barry, Leino, E.Victor, Shorofsky, Stephen R, Kavesh, Neal G, Peters, Robert W, Gold, Michael R
• Format: Article
• Language: English
• Subjects: Amiodarone - therapeutic use; Anti-Arrhythmia Agents - therapeutic use; Biological and medical sciences; Body Constitution; Cardiovascular disease; Cohort Studies; Coronary vessels; Defibrillators, Implantable; Diseases of the cardiovascular system; Echocardiography; Electric Countershock - methods; Electrodes, Implanted; Equipment Design; Evaluation Studies as Topic; Female; Forecasting; Heart - diagnostic imaging; Humans; Hypertrophy, Left Ventricular - diagnostic imaging; Logistic Models; Male; Medical sciences; Middle Aged; Multivariate Analysis; Odds Ratio; Prospective Studies; Radiography; Radiotherapy. Instrumental treatment. Physiotherapy. Reeducation. Rehabilitation, orthophony, crenotherapy. Diet therapy and various other treatments (general aspects); Risk Factors; Transplants & implants
• ISSN: 0002-9149; 1879-1913
• DOI: 10.1016/S0002-9149(96)00702-3

Nonthoracotomy and, more recently, transvenous lead systems have become routine for initial implantable cardioverter-defibrillator (ICD) placement. Previous studies of clinical predictors of nonthoracotomy defibrillation energy requirements evaluated multiple complex lead systems that included subcutaneous patches. However, the predictors of an adequate transvenous defibrillation threshold (DFT) have not been assessed previously. Accordingly, the present study is a prospective evaluation of DFT using a uniform testing protocol in 119 consecutive patients undergoing ICD implantation with a single transvenous lead. For each patient, 38 parameters were assessed including standard clinical, echocardiographic, and radiographic measures. An adequate monophasic DFT (≤20 J) was achieved in 76% of patients. Multivariable analysis revealed 3 independent factors predictive of a high threshold: preoperative amiodarone use (odds ratio = 5.8, p ≤0.002), echocardiographic measures of left ventricular dilation (odds ratio = 0.47, p ≤0.005) and body size (odds ratio = 0.51, p ≤0.006). Patients receiving amiodarone who also had left ventricular dilation constitute a group at considerable (69%) risk for having a high DFT. In contrast, patients with neither of these risk factors have only an 11% chance of having a high threshold. We conclude that an adequate transvenous DFT can be predicted from simple clinical parameters.