Cardiovascular presentations during the COVID-19 pandemic: an interrupted time series analysis

Background: The broader implications of the Coronavirus disease 2019 pandemic on cardiovascular hospitalizations remain unclear. We aimed to assess trends in cardiovascular presentations during the Coronavirus disease 2019 pandemic.

Methods: This multicentre study examined cardiovascular presentations from March 2018 to February 2023. Patients with cardiovascular presentations were identified through administrative health records using ICD-10-AM diagnosis codes. Four key study periods were analysed: T0-pre-pandemic, T1-first lockdown, T2-easing of restrictions and T3-release of restrictions and widespread vaccination. Interrupted time series analysis was used to predict weekly cardiovascular presentations, with the mean difference between actual and predicted numbers assessed for significance.

Results: Overall, 116 518 patients were included across three major public hospitals in Australia. Cardiovascular presentations were significantly lower in T1 than predicted, with a mean decline of 13.1% (SD 16.2%; P = 0.004). There was a significant difference between the expected and actual number of most cardiovascular presentations in T2 and T3, apart from a significant reduction in cardiomyopathy and heart failure presentations during T3 (4.5% [SD 23.7%]; P = 0.007).

Conclusions: Cardiovascular presentations were significantly lower during the initial lockdown phase of the COVID-19 pandemic; this attenuated with easing of social restrictions and widespread vaccination, except for persistent reduction in cardiomyopathy and heart failure presentations.