Respiratory System Function in Patients after Minimally Invasive Aortic Valve Replacement Surgery

OBJECTIVE: The aim of the study was to comparatively analyze respiratory system function after minimally invasive, through right minithoracotomy aortic valve replacement (RT-AVR) to conventional AVR. METHODS: Analysis of 201 patients scheduled for RT-AVR and 316 for AVR between January 2010 and November 2013. Complications of the respiratory system and pulmonary functional status are presented. RESULTS: Complications of the respiratory system occurred in 16.8% of AVR and 11.0% of RT-AVR patients (P = 0.067). The rate of pleural effusions, thoracenteses, pneumonias, or phrenic nerve dysfunctions was not significantly different between groups. Perioperative mortality was 1.9% in AVR and 1.0% in RT-AVR (P = 0.417). Mechanical ventilation time after surgery was 9.7 ± 5.9 hours for AVR and 7.2 ± 3.2 hours for RT-AVR patients (P < 0.001). Stroke (odds ratio [OR] = 13.4, P = 0.008), increased postoperative blood loss (OR = 9.6, P < 0.001), and chronic obstructive pulmonary disease (OR = 7.7, P < 0.001) were risk factors of prolonged mechanical lung ventilation. A week after surgery, the results of most pulmonary function tests were lower in the AVR than in the RT-AVR group (P < 0.001 was seen for forced expiratory volume in the first second, vital capacity, total lung capacity, maximum inspiratory pressure and maximum expiratory pressure, P = 0.377 was seen for residual volume). CONCLUSIONS: Right anterior aortic valve replacement minithoracotomy surgery with single-lung ventilation did not result in increased rate of respiratory system complications. Spirometry examinations revealed that pulmonary functional status was more impaired after AVR in comparison with RT-AVR surgery.