The results of cardiac surgery during the COVID-19 pandemic compared with previous years: a propensity weighted study of outcomes at six months

Objectives In addition to excess mortality due to COVID-19, the pandemic has been characterised by excess mortality due to non-COVID diagnoses and consistent reports of patients delaying seeking medical treatment. This study seeks to compare the outcomes of cardiac surgery during and before the COVID-19 pandemic. Design Our institutional database was interrogated retrospectively to identify all patients undergoing one of three index procedures during the first six months of the pandemic and the corresponding epochs of the previous five years. Setting A regional cardiothoracic centre. Participants All patients undergoing surgery during weeks #13-37, 2015-2020. Main outcome measures Propensity score weighted analysis was employed to compare the incidence of major complications (stroke, renal failure, re-ventilation), 30-day mortality, six month survival and length of hospital stay between the two groups. Results There was no difference in 30-day mortality (HR = 0.76 [95% CI 0.27-2.20], p = 0.6211), 6-month survival (HR = 0.94 [95% CI 0.44-2.01], p = 0.8809) and duration of stay (SHR = 1.00 (95% CI 0.90-1.12), p = 0.959) between the two eras. There were no differences in the incidence of major complications (weighted chi-square test: renal failure: p = 0.923, stroke: p = 0.991, new respiratory failure: p = 0.856). Conclusions Cardiac surgery is as safe now as in the previous five years. Concerns over the transmission of COVID-19 in hospital are understandable but patients should be encouraged not to delay seeking medical attention. All involved in healthcare and the wider public should be reassured by these findings.