Ten-year experience of an invasive cardiology centre with out-of-hospital cardiac arrest patients admitted for urgent coronary angiography.

BACKGROUND AND AIM The aim of the study was to evaluate survival and neurological function of out-of-hospital cardiac arrest (OHCA) patients admitted for urgent coronary angiography (UCA) with a view to percutaneous coronary intervention (PCI). METHODS Hospital records of OHCA patients admitted to an invasive cardiology centre (providing 24 h a day/7 days a week service) in 2000-2010 were reviewed retrospectively, and similar data collected in 2011 were reviewed prospectively. Reports from the pre-hospital phase from emergency medical services (EMS) in Krakow were also analysed. Long-term follow-up data were collected by retrieving records from other hospitals (for patients transferred after UCA/PCI) and by phone calls to patients or their relatives. RESULTS In 2000-2011, 405 OHCA patients were admitted for UCA/PCI. Most (78%) had ventricular fibrillation (VF) or ventricular tachycardia (VT) as the primary mechanism of cardiac arrest (asystole: 13%, pulseless electrical activity: 3%, unknown: 6%). The mean patient age was 61 (range 20-85) years, and 81% were males. On admission, about 70% of patients were unconscious and 11% were in cardiogenic shock. The mean resuscitation time (time to return of spontaneous circulation [ROSC]) was 26.7 (range 1-126) min. ST-T changes seen in an electrocardiogram recorded after ROSC included ST elevation and depression in 52% of cases, only ST depression in 21% of cases, only ST elevation in 17% of cases, unspecific changes (due to intraventricular conduction disturbances) in 7% of cases, negative T waves in 3% of cases, and no changes in 0.5% of cases. Coronary angiography revealed acute coronary occlusion in 48% of cases, critical coronary stenosis (> 90%) in 26% of cases, other significant coronary lesions (> 50% stenosis) in 15% of cases, and non-significant lesions in 11% of cases. An acute coronary syndrome (ACS) was diagnosed in 82% of patients (75% STEMI, 25% NSTEMI), and other cardiac cause (mostly ischaemic cardiomyopathy) was identified in 13% of patients. Among OHCA patients diagnosed with ACS, PCI was performed in 90% and additional 4% underwent coronary artery bypass grafting. Overall success rate of PCI, defined as TIMI 3 flow plus residual stenosis < 50% and resolution of ST elevation after PCI by > 30%, was 70%. Survival to hospital discharge in the entire group of OHCA patients was 63% and 30-day survival with good neurological outcomes (defined as Cerebral Performance Category 1 or 2) was 49%. Among patients who were initially unconscious, those figures were 52% and 33%, respectively. During long-term follow-up (up to 12 years), 49% of patients were alive and 42% had good neurological function (87% of those who survived). In multivariate analysis, independent predictors of survival with good neurological outcomes were preserved consciousness on admission, absence of shock, cardiac arrest witnessed by medical personnel, VF/VT as a primary mechanism of cardiac arrest, and preserved renal function. Successful PCI predicted survival until hospital discharge only when the neurological status of the patients was not taken into account. CONCLUSIONS The most important cause of OHCA is coronary artery disease, in particular ACS. UCA and PCI seem to be important elements of appropriate post-resuscitation care because such treatment could improve survival but it is still unclear whether PCI might influence neurological outcomes as well.