Significant deterioration of cardiopulmonary exercise tolerance after minimally invasive aortic valve replacement

Abstract

This master thesis investigated the impact of minimally invasive aortic valve replacement (mAVR) on cardiopulmonary and muscular oxidative function during exercise early after surgery and explored the pre- and perioperative factors related to anomalous recovery of these functions during exercise testing.

After submaximal cardiopulmonary exercise testing of 16 participants with severe aortic stenosis at three time points (pre-operative, 5 days and 3 weeks postoperative), using 30 matched healthy controls as a reference standard, the following results were obtained:

Cardiopulmonary exercise tolerance was significantly lowerd in patients with severe aortic stenosis and further deteriorated early after mAVR. Therefore, rehabiliation should emphasis on cardiopulmonary exercise programs. Gender, body mass index, perioperative mechanical ventilation time and preoperative respiratory exchange ratio (RER), minute ventilation and tidal volume were positively correlated with postoperative deterioration of cardiopulmonary function during exercise, whereas a negative correlation was observed for preoperative EqCO2 and oxygen pulse.