Carotid body denervation prevents pulmonary edema, attenuates left ventricular remodeling and restores normal autonomic balance in chronic heart failure after myocardial infarction (709.5)

Abstract

Background: The hypersensitive peripheral chemoreflex induces sympathoexcitation and vagolysis and is known to associate with the poor prognosis of chronic heart failure (CHF). We hypothesized that denervation of carotid body (CBD) improves CHF and restore the normal autonomic balance in a rat model of myocardial infarction (MI)‐induced CHF. Methods: We created MI‐induced CHF in rats. Surviving rats at 4 weeks after MI were randomized into CBD (n=10) and sham‐operated (Sham; n=10) group. To establish CBD, we removed the tissues around the carotid bifurcation. Two months after CBD, we evaluated physiological and histological findings. Results: CBD significantly reduced biventricular weight (2.9±0.1 vs. 3.3±0.1 g/kg, p<0.05), lung weight (5.6±0.4 vs. 8.1±0.3 g/kg, p<0.05), LV end‐diastolic pressure (13.7±3.2 vs. 28.3±3.1 mmHg, p<0.05) and heart rate (HR) (336±6 vs. 364±5 bpm, p<0.05). Power spectral analysis of HR demonstrated the increased power in the high frequency range (29.0±8.2 vs. 81.0±9.5 n.u., p<0.05) indicating the restoration of vagal tone. Histologocal analysis showed CBD decrease fibrosis and the invasion of macrophages in myocardium. Conclusion: CBD prevents pulmonary edema, attenuates LV remodeling and restores normal autonomic balance in CHF rats. CBD can be a novel neuro‐modulating therapy for CHF patients.