The Influence of Patient Strength, Aerobic Capacity and Body Composition Upon Outcomes After Coronary Artery Bypass Grafting

Background: Physical activity, physical fitness and body habitus of patients may be important predictors of outcomes after cardiac surgery. This study sought to quantify physical fitness and determine whether components of fitness enhance the prediction of outcomes in a group of patients undergoing coronary artery bypass grafting. Methods: A group of 200 patients were evaluated prior to coronary artery bypass surgery. A Veterans Specific Activity Questionnaire (VSAQ) measured aerobic capacity. A grip dynamometer assessed strength. Skin-fold thickness was used to calculate percent body fat and lean body mass index. Patients were divided into low risk (0 - 2.5 %) and high risk (> 2.5 %) groups based on the STS National Cardiac Surgery Database prediction of operative mortality. Results: Patients with both a high percent body fat and a low VSAQ were at higher risk for at least one serious complication (p < 0.05) and a longer postoperative length of stay (p < 0.05). Conclusion: This study suggests: 1) An index of physical fitness can be obtained preoperatively in cardiac surgical patients; 2) This information aids in the prediction of operative risk.

Key words:

CABG outcomes - Stongth, Fitness - Body composition

References

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1 The material of this manuscript was presented at the International Congress on “Risk Stratification in Cardiac and Thoracic Surgery”, October 15/16, 1999, Cologne, Germany