Prognostic significance of shockable and non-shockable cardiac arrest in ST-segment elevation myocardial infarction patients undergoing primary angioplasty

Abstract

ObjectiveTo determine, in patients with ST-segment Elevation Myocardial Infarction (STEMI) undergoing primary percutaneous coronary intervention (PPCI), the prognostic weight of cardiac arrest (CA) according to the type of rhythm (shockable vs. non-shockable). MethodsWe prospectively enrolled 3278 consecutive STEMI patients undergoing PPCI. Multivariable Cox regression was used to establish the relation to 1-year cardiac mortality of both type of CA. In patients suffering from CA we identified predictors of both poor neurological outcome (cerebral performance categories 3–5) and cardiac mortality at 1year. ResultsThe incidence of CA was 7.26% (n=238). Of these, 196 (5.98%) had an initial shockable rhythm and 42 (1.28%) a non shockable rhythm. During 1-year follow up 311(9.48%) patients died from cardiac causes. Shockable rhythm (adjusted-HR=1.61; 95%CI 1.08–2.43, p=0.02) and non-shockable rhythm (adjusted-HR=3.83; 95%CI 2.36–6.22, p<0.001) were independently associated with 1-year cardiac mortality. Among patients with CA those with shockable rhythm had a lower risk of poor neurological outcome at 1year follow up (adjusted OR=0.22: 95%CI; 0.08–0.55, p=0.001). Independent predictors of 1-y cardiac mortality were: non shockable rhythm (adjusted HR=2.6; 95%CI; 1.48–4.5, p=0.001), crew-witnessed CA, diabetes mellitus, left ventricle ejection fraction and creatinine on admission. There was a significant interaction between type of rhythm and crew-witnessed CA (p=0.026). ConclusionsIn patients with STEMI undergoing PPCI patients with both shockable and non shockable CA are at increased risk of 1-year cardiac mortality. Among patients with CA those with non shockable rhythm have an higher risk of both poor neurological outcome and cardiac mortality at 1year.