Background: Cardiac patients whose non-emergency cardiovascular intervention has been postponed during the COVID-19 pandemic showed poor clinical outcome up to 1 year later. Data on long-term effects of deferred treatment are currently lacking.

Objectives: This study sought to assess clinical outcomes through 3 years following deferral of non-emergency cardiac interventions.

Methods: This observational case-control study included consecutive patients whose non-emergency cardiac intervention has been postponed during COVID-19-related lockdown between March 19th and April 30th 2020 (n=178). Primary endpoint events including a composite of emergency cardiovascular hospitalization and death were analyzed through 3 years and compared to a seasonal control group undergoing non-emergency interventions in the corresponding time period 2019 (n=214).

Results: The mean time to follow-up was 530 days in the deferred patients and 744 days in the control group, respectively. During the 3-year follow-up the combined endpoint of death and emergency cardiovascular hospitalization occurred in 33.7 % of patients with a postponed cardiac intervention (N=60) and was similar to the rate of the seasonal control group in 2019 (32.2 %; HR 1.35, CI 0.96 - 1.91; P=0.088) (Figure 1). However, within the first 24 months primary endpoint events occurred significantly more often in deferred patients compared to patients receiving their intervention as scheduled (HR 1.77, CI 1.20-2.60; P=0.003) (Figure 2). In deferred patients affected by a primary endpoint event within the first 24 months, NTproBNP levels were significantly higher at the time of the performed intervention (P=0.003, AUC 0.768, optimum cut-off 808.5 pg/ml, sensitivity 84.2 %, specifity 65.8 %).

Conclusion: Deferral of non-emergency cardiovascular interventions is associated with worse clinical outcome up to 24 months later. Thereafter, outcomes were comparable to patients receiving their procedures as scheduled. In the future, these findings can help to improve resource allocation in times of limited hospital capacity.