Recovery in cardiopulmonary and oxidative muscular function during exercise after minimally invasive aortic valve replacement

Abstract

Background: Aortic valve stenosis (AS) is one of the greatest burdens in elderly people. The only effective treatment is aortic valve replacement by surgery. However, it remains unidentified how the recovery in cardiopulmonary and muscular function after minimally invasive aortic valve replacement (mini-AVR) is manifested.

Methods: This was a combination of a cross-sectional and prospective observational study. 14 AS patients were followed for up to 3 weeks after mini-AVR surgery and examined were submaximal cardiopulmonary exercise test at 25% of maximum workload, echocardiography and cardiovascular disease risk were assessed.

Results: During exercise, significantly elevated EqO2 and EqCO2 were observed (p = 0,002 vs. p = 0,008) compared to healthy controls before mini-AVR surgery. At 5 days, both EqO2 and EqCO2 during exercise were significantly elevated (p = 0,007 vs. p =0,008). Exercise MRT was significantly slower at five days (p = 0,036) versus exercise MRT measured prior to surgery. At 3 weeks, EqCO2 during exercise was significantly lower (p = 0,021) and normalized. Accelerated exercise MRT was observed at 3 weeks. Furthermore, cross-clamp time was independently related to exercise MRT at three weeks after mini-AVR surgery (p = 0,001).

Conclusion Systematic significant deterioration in exercise performance was observed after mini-AVR, which is probably related to ventilation perfusion mismatch. Need for improved early post-operative treatment is of great importance.