Passive epicardial containment prevents ventricular remodeling in heart failure

Background. We examined the effects of passive containment of the cardiac ventricles with a surgically placed epicardial prosthetic wrap on indexes of left ventricular (LV) remodeling in dogs with heart failure. Methods. Heart failure (LV ejection fraction 30% to 40%) was produced in 12 dogs by intracoronary microembolization. Six dogs underwent mid-sternotomy and pericardiotomy with placement of a preformed-knitted polyester device ( Acorn Cardiac Support Device [CSD], Acorn Cardiovascular, Inc, St. Paul, MN) snugly around the ventricles and anchored to the atrioventricular groove. Six dogs did not undergo surgery and served as controls. Dogs were followed for 3 months prior to sacrifice. Results. In controls, LV end-diastolic volume increased after 3 months (67 ± 12 versus 83 ± 8 ml; p = 0.04), while in CSD-treated dogs, it decreased (68 ± 10 versus 61 ± 10 ml; p = 0.002). CSD-containment of LV size was associated with increased LV systolic fractional area of shortening, while in controls, fractional area of shortening decreased. CSD-treated dogs also showed amelioration of myocyte hypertrophy and attenuation of interstitial fibrosis compared to controls. Conclusions. In dogs with heart failure, passive epicardial containment of the ventricles with the Acorn CSD ameliorates LV remodeling and improves LV systolic function.