Heart Failure: LV Remodeling - DOR procedure

The treatment of heart failure has evolved significantly over the past few years because of significant advances in three avenues of treatment. New drug regimens, particularly those focused on ACE inhibitor and beta blocker therapies, have significantly improved patient outcomes. Advanced pacemaker regimens and devices (particularly bi-ventricular pacemakers) have produced dramatic improvements in ventricular function and patient survival. A better understanding of the functional geometry of the failing left ventricle has led to the development of surgical remodeling procedures (such as the Dor Operation) which effectively converts the spherical failing ventricle to an ellipsoid which allows more effective left ventricular contraction and ejection mechanics. Each of these therapies has a unique yet complementary role in the treatment of end-stage ventricular function patients.

The Dor Procedure (JTCVS 1998; 116: 50-9) is of particular interest to us because of its effectiveness in producing very significant improvements in left ventricular function. Large transmural infarctions cause both early and late distortion of the ventricular wall. The abnormal shape raises wall tension producing adverse remodeling, mechanical disadvantages, and heart failure. Scarred segments do not contract to support cardiac output and thereby adversely affect non-infarcted muscle function leading to chronic reduction in the left ventricular ejection fraction with subsequent left ventricular failure.

The Dor procedure involves placing an endoventricular circular purse string suture at the base of the infarcted ventricle. When tied down, this circular suture helps to restore a more normal oval curvature of the ventricle. The remaining ventricular defect is closed with a pericardial patch.

Dramatic improvements in ventricular function have been reported.   In one series of 100 patients, the EF increased by approximately 43% (from 23% to 40%) and early PCWP fell. 57 patients were in NYHA class I-II, 6 in Class III, and one in Class IV. There were 19 deaths, five due to heart failure, 4 non cardiac, 3 unknown, and sudden death in one.

We have been very pleased with our results using this procedure in this very difficult patient population.