Outcomes With Early Cardiac Catheterization in Out of Hospital Cardiac Arrest Survivors and Utility of a Prognostic Scoring System

Abstract

Objectives A retrospective study in patients presenting out of hospital cardiac arrest (OHCA) to assess the impact of early cardiac catheterization on survival and cerebral performance category (CPC) on discharge. Background The role of early coronary angiography in OHCA patients remains controversial. The cardiac arrest hospital prognosis (CAHP) scoring system has not been validated in the US population. Methods Inclusion criteria were OHCA patients with a sustained return of spontaneous circulation (ROSC), presumed cardiac cause of arrest, and elements to calculate CAHP score. We compared in-hospital mortality rates and final inpatient CPC in patients who underwent early cardiac catheterization to those with delayed or no cardiac catheterization. We assessed the performance of the CAHP score in the entire OHCA population using receiver-operator curve (ROC) analysis. Results A hundred and fifty-eight patients were included, of which 39 underwent early cardiac catheterization. The mortality rate of the early catheterization group was lower than the delayed or no catheterization group (41% vs 61.3%, p=0.02); the Early cardiac catheterization group had more favorable final hospital CPC scores overall (53.8% vs 24.3%, p<0.001). However, when risk-adjusted, there was no benefit in early catheterization for mortality or CPC level in any of the CAHP score subgroups. CAHP scores showed good discrimination with c-statistics of 0.85 for mortality and 0.90 for the CPC category. Conclusion Early use of cardiac catheterization in OHCA patients with sustained ROSC was not associated with lower mortality rates or higher rates of favorable neurologic recovery when adjusted for baseline risk factors in each of the different CAHP score-based sub-groups. This was despite a higher proportion of patients with STEMI in the early catheterization group. We demonstrated a good fit between observed outcomes and outcomes predicted by the CAHP scoring system.

Keywords: 30 day mortality; cardiac arrest hospital prognosis score; coronary angiography; neurologic prognosis; out of hospital cardiac arrest.

Figure 1. Odds Ratio Estimate of Mortality (left) and Unfavorable Cerebral Outcome (right) for Early vs Delayed Catheterization Conditioned on Low, Medium and High CAHP Scores

Figure 2. CAHP Score Validation for Mortality

The CAHP score (in continuous scale) predicts mortality with an accuracy of 84.5% (C-statistic 0.845) and the CAHP score range (grouped in to high, medium and low level) predict the mortality with an accuracy of 78.20% (C-statistic 0.782).