Procedure duration is an important predictor of patient outcomes in surgery. However, the relationship between procedure duration and adverse events in congenital cardiac catheterization is largely unexplored.

All cases entered into the Congenital Cardiac Catheterization Project on Outcomes from 2014 to 2017 were included. Cases were ordered from shortest to longest case length, minus time spent managing adverse events, for each case type. The outcomes, Level 3bc/4/5 and 4/5 adverse event rates, were calculated for cases above and below the 75th percentile for case length. To identify an independent relationship between case length and outcomes, the case length percentile was added to the CHARM II risk model.

Among 14,704 catheterizations, longer cases (>75th percentile for case length) had Level 4/5 rates that were 2.2% and 2.7% compared to cases ≤75th percentile with adverse event rates of 0.9% and 1.4% for diagnostic and interventional cases, respectively. Level 3bc/4/5 rates were 5.0% and 8.4% in longer cases compared to 2.4% and 5.4% for diagnostic and interventional cases, respectively. After adding case length to the CHARM II risk model, case length 50th–75th percentile had an odds ratio (OR) of 1.4, 75th–90th percentile an OR of 1.56, and >90th percentile an OR of 2.24 as compared to cases with case length <50th percentile (p ≤ 0.001 for all).

Longer case lengths are associated with clinically important and life-threatening adverse events in congenital cardiac catheterization, even after accounting for known risk factors. Case length may be an important target for future quality improvement work.