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Predictive risk factors in double-valve replacement (AVR and MVR) compared to isolated aortic valve replacement.

BACKGROUND
The operative risk of combined aortic and mitral surgery is still between 5 and 13 %, whereas isolated AVR normally causes complications in less than 4 % of all patients. Thus, it was the aim of the study to compare both procedures and to evaluate risk stratification in our patient cohort.


PATIENTS AND METHODS
The inhospital mortality and complication rates were analyzed in both groups over a period of 4 years. There were 396 patients with isolated AVR, and 98 patients with AVR and MVR. For both groups, we investigated 16 possible risk factors for perioperative death or severe complications, such as low cardiac output syndrome (LCOS). The risk factors were analyzed by univariate analysis, and factors with P < 0.01 were entered into a multivariate analysis.


RESULTS
There were 11/396 perioperative deaths in patients with AVR (2.8 %) compared to 5/98 (5.1 %) in DVR. The incidence of major complications was 5.3 % in AVR vs. 11.2 % in DVR. As risk factors ( P < 0.05) for death, we found in AVR: former cardiac surgery, aortic stenosis, and pulmonary arterial pressure > 55 mmHg. In patients with DVR, we additionally found: left atrial pressure (LAP) > 20 mmHg and creatinine > 2 mg/dl. Risk factors for severe complications in AVR were: former cardiac surgery and creatinine > 2 mg/dl, in cases of DVR, additionally: tricuspid valve disease (TVD) and LAP > 20 mmHg.


CONCLUSIONS
Our analysis of risk factors shows that in patients with DVR preoperative parameters, which sometimes are estimated to be unimportant, may cause an adverse outcome. The operation should be carried out before reaching advanced or even end-stage heart failure, and more attention should be paid to an individual perioperative concept and optimized myocardial protection in such patients.