Study design and data collection:
The study is a retrospective propensity score matched study that was
conducted at a tertiary Cardiac center It included adult patients above
or equal to 18 years who underwent any cardiac surgery with
cardiopulmonary bypass, had congestive heart failure (either decreased
left ventricular EF or severe left-sided valvular heart disease (based
on transthoracic echocardiography) and had preoperative PFT during the
time period from May 2015 to December 2019. Patients who did not have
preoperative PFT were excluded from the study.
Data were collected on patients’ demographics, preoperative PFT
parameters, operative data and postoperative data and complications from
electronic medical records. Echocardiographic parameters were obtained
from the echocardiographic laboratory databases.
The pulmonary functions test results were classified into obstructive or
restrictive patterns and then classified in severity according to the
American Thoracic Society (ATS) grading system 6,7.
The patients were divided into two groups: Group 1; who had a normal or
mild reduction in PFT and Group 2; who had moderate to severe reduction
in PFT. The postoperative outcomes, including pulmonary complications,
were compared between the two groups.
The Institutional Review Board approved the data collection of this
study, and they waived the need for patients’ consent because of the
retrospective nature of the study.