Mild hypothermia delays the development of stone heart from untreated sustained ventricular fibrillation--a cardiovascular magnetic resonance study

• Published in: Journal of cardiovascular magnetic resonance 2011-03, Vol.13 (1), p.17-17, Article 17
• Main Authors: Sorrell, Vincent L, Paleru, Vijayasree, Altbach, Maria I, Hilwig, Ronald W, Kern, Karl B, Gaballa, Mohamed, Ewy, Gordon A, Berg, Robert A
• Format: Article
• Language: English
• Subjects: Animals; Cardiac arrhythmia; Care and treatment; Colleges & universities; Data collection; Diagnosis; Disease Models, Animal; Female; Health aspects; Heart Arrest - diagnosis; Heart Arrest - etiology; Heart Arrest - physiopathology; Heart Arrest - prevention & control; Hypertrophy, Left Ventricular - diagnosis; Hypertrophy, Left Ventricular - etiology; Hypertrophy, Left Ventricular - physiopathology; Hypertrophy, Left Ventricular - prevention & control; Hypothermia; Hypothermia, Induced; Ischemia; Magnetic Resonance Imaging; Medicine; Random Allocation; Risk factors; Swine; Time Factors; Ventricular fibrillation; Ventricular Fibrillation - complications; Ventricular Fibrillation - diagnosis; Ventricular Fibrillation - physiopathology; Ventricular Fibrillation - therapy; Ventricular Function, Left; Ventricular Function, Right
• ISSN: 1097-6647; 1532-429X; 1532-429X
• DOI: 10.1186/1532-429X-13-17

'Stone heart' resulting from ischemic contracture of the myocardium, precludes successful resuscitation from ventricular fibrillation (VF). We hypothesized that mild hypothermia might slow the progression to stone heart. Fourteen swine (27 ± 1 kg) were randomized to normothermia (group I; n=6) or hypothermia groups (group II; n=8). Mild hypothermia (34 ± 2 °C) was induced with ice packs prior to VF induction. The LV and right ventricular (RV) cross-sectional areas were followed by cardiovascular magnetic resonance until the development of stone heart. A commercial 1.5T GE Signa NV-CV/i scanner was used. Complete anatomic coverage of the heart was acquired using a steady-state free precession (SSFP) pulse sequence gated at baseline prior to VF onset. Un-gated SSFP images were obtained serially after VF induction. The ventricular endocardium was manually traced and LV and RV volumes were calculated at each time point. In group I, the LV was dilated compared to baseline at 5 minutes after VF and this remained for 20 minutes. Stone heart, arbitrarily defined as LV volume