Respiratory dysfunction prediction in patients after the left ventricle geometric reconstruction

Abstract

Relevance. One of the most common complications after cardiac surgery is respiratory dysfunction (RD). The high-risk group includes patients after the left ventricle geometric reconstruction (LVGR) due to the presence of chronic heart failure, as well as the complexity and extent of the surgical intervention. At the moment, in clinical practice there is no uniform approach to predicting RD in patients in this group. The aim: to identify predictors of the development of RD in the early postoperative period in patients after LVGR. Materials and methods. The study included 54 patients who underwent LVGR surgery. Two groups of patients were identified: group I — patients without respiratory complications in the early postoperative period (n = 34); group II — patients with RD in the early period (n = 20). Cardiac function, respiratory system and gas exchange parameters were assessed in the pre- and early postoperative period. Results and Discussion. Echocardiography and spirometry indices in the group with RD were reduced before surgery relative to group I (FVC by 10.9 %, p = 0.009; EDV by 27 %, p = 0.004). Patients with RD on the first day after surgery were characterized by a pronounced disturbance in gas exchange compared to patients in group I (PaO2/FiO2 decreased by 45.1 %, p 0.001; Qs/Qt increased by 71.4 %, p 0.001). A multifactorial model was developed, which included three basic predictors of RD development: FVC, FEF50 and EDV. With a decrease in model indicators by 1 %, the risk of developing RD increased by 33.5 %, 24.8 % and decreased by 6.5 %, respectively. According to ROC-analysis, the most significant indicators were FEV3 (AUC 0.829 ± 0.079) and EDV (0.838 ± 0.087). To assess the risk of developing RD, a classification tree was constructed. Node 7 is characterized by the highest risk with the following parameters: FVC ≤ 89.5 %, EDV 173.2 ml, FEF50 ≤ 78.9 %. Conclusion. Impaired gas exchange on the first day after surgery was detected in all studied patients, however, pronounced RD was observed precisely in patients with the most reduced parameters of the cardiorespiratory system before surgery. The developed model for predicting RD in patients after LVGR makes it possible to assess the risk of respiratory complications at the surgical planning stage and prepare the patient’s cardiorespiratory system for the upcoming surgical intervention.

Keywords

• the left ventricle geometric reconstruction
• respiratory dysfunction
• prognosis
• predictors
• spirometry