Predictors of mortality after aortic valve replacement

Complex Aortic Valve Surgery for Endocarditis Using the Beating-Heart Technique

Objective

Surgical outcomes of aortic valve surgery for endocarditis are poor. Postoperative deterioration of left ventricular (LV) function may contribute to this process. To enhance preservation of myocardial function during aortic valve surgery, we have used a beating-heart technique of myocardial protection without cardioplegic arrest. The aim of this article is to report our initial clinical experience with this technique.

Methods

We identified 30 consecutive patients with endocarditis who underwent aortic valve repair (one patient) or replacement using either a mechanical prosthesis (four patients) or a biologic prosthesis (25 patients) with beating-heart technique. There were 22 men and eight women (mean age 52.8 ± 16.1 years). There were one elective, 22 urgent/emergent, and seven “salvage” operations. Two patients had preoperative stroke, five respiratory failure, three renal failure, 12 congestive heart failure, eight septic shock, and one previous coronary artery bypass grafting. The etiology of the infection was identified in 15 patients (50%). Ten patients had severe, seven moderate, and four mild aortic insufficiency. All patients had vegetations, four had annular abscesses, and two had intracardiac fistulas.

Results

Eight patients (26.6%) had redo procedures. Concomitant procedures included aortic and mitral valve procedure (14 patients), tricuspid valve procedure (two patients), and coronary artery bypass grafting (one patient). Aortic annular reconstruction was required in four patients (13.2%). Total CPB time was 125 ± 67 minutes. Intra-aortic balloon pump was needed in one patient. Two patients (6.6%) had a stroke unrelated to air embolism. Mean follow-up was 7.9 ± 12 months. Early mortality (30 days) was 13.3% (four patients), and late mortality was 10% (three patients). Total mortality was 18% in urgent/emergent cases, and 42% in salvage operations. There was no statistical difference between preoperative and postoperative echocardiographic values of LV function (ejection fraction and fractional shortening). LV end-diastolic dimension decreased postoperatively (P = 0.03), whereas LV end-systolic dimension and left atrial size were unchanged.

Conclusions

Our study did not show improved survival benefits of beating-heart aortic valve surgery compared with historical series in which conventional myocardial protection was used. However, our findings suggest that beating-heart technique is an alternative strategy of myocardial protection that may contribute to preservation of LV function in patients undergoing complex operations for aortic valve endocarditis.