ABSTRACT
BACKGROUND: Clinical features among patients with refractory out-of-hospital cardiac arrest (OHCA) and initial shockable rhythms of ventricular fibrillation/pulseless ventricular tachycardia are not well-characterized. METHODS: We compared clinical characteristics and coronary angiographic findings between patients with refractory OHCA (incessant ventricular fibrillation/pulseless ventricular tachycardia after ≥3 direct-current shocks) and those without refractory OHCA. RESULTS: Between 2014 and 2018, a total of 204 patients with ventricular fibrillation/pulseless ventricular tachycardia OHCA (median age 62; males 78%) were divided into groups with (36%, 74/204) and without refractory arrest (64%, 130/204). Refractory OHCA patients had longer cardiopulmonary resuscitation (23 versus 15 minutes), more frequently required ≥450 mg amiodarone (34% versus 3.8%), and had cardiogenic shock (80% versus 55%) necessitating higher adrenaline dose (4.0 versus 1.0 mg) and higher rates of mechanical ventilation (92% versus 74%; all P<0.01). Of 167 patients (82%) selected for coronary angiography, 33% (n=55) had refractory OHCA (P=0.035). Significant coronary artery disease (≥1 major vessel with >70% stenosis) was present in >70% of patients. Refractory OHCA patients frequently had acute coronary occlusion (64% versus 47%), especially left circumflex (20% versus 6.4%) and graft vessel (7.3% versus 0.9%; all P<0.05) compared with those without refractory OHCA. Refractory OHCA group had higher in-hospital mortality (45% versus 30%, P=0.036) and greater new requirement for dialysis (18% versus 6.3%, P=0.011). After adjustment, refractory OHCA was associated with over 2-fold higher odds of in-hospital mortality (odds ratio, 2.28 [95% CI, 1.06-4.89]; P=0.034). CONCLUSIONS: Refractory ventricular fibrillation/pulseless ventricular tachycardia OHCA was associated with more intensive resuscitation, higher rates of acute coronary occlusion, and poorer in-hospital outcomes, underscoring the need for future studies in this extreme-risk subgroup.
Subject(s)
Cardiopulmonary Resuscitation , Coronary Occlusion , Emergency Medical Services , Out-of-Hospital Cardiac Arrest , Tachycardia, Ventricular , Male , Humans , Middle Aged , Ventricular Fibrillation/diagnosis , Ventricular Fibrillation/therapy , Ventricular Fibrillation/complications , Out-of-Hospital Cardiac Arrest/diagnosis , Out-of-Hospital Cardiac Arrest/therapy , Coronary Occlusion/complications , Treatment Outcome , Tachycardia, Ventricular/diagnosis , Tachycardia, Ventricular/therapyABSTRACT
BACKGROUND: Clinical factors favouring coronary angiography (CA) selection and variables associated with in-hospital mortality among patients presenting with out-of-hospital cardiac arrest (OHCA) without ST-segment elevation (STE) remain unclear. METHODS: We evaluated clinical characteristics associated with CA selection and in-hospital mortality in patients with OHCA, shockable rhythm and no STE. RESULTS: Between 2014 and 2018, 118 patients with OHCA and shockable rhythm without STE (mean age 59; males 75%) were stratified by whether CA was performed. Of 86 (73%) patients undergoing CA, 30 (35%) received percutaneous coronary intervention (PCI). CA patients had shorter return of spontaneous circulation (ROSC) time (17 vs. 25 min) and were more frequently between 50 and 60 years (29% vs. 6.5%), with initial Glasgow Coma Scale (GCS) score >8 (24% vs. 6%) (all p < 0.05). In-hospital mortality was 33% (n = 39) for overall cohort (CA 27% vs. no-CA 50%, p = 0.02). Compared to late CA, early CA ( ≤ 2 h) was not associated with lower in-hospital mortality (32% vs. 34%, p = 0.82). Predictors of in-hospital mortality included longer defibrillation time (odds ratio 3.07, 95% confidence interval 1.44-6.53 per 5-min increase), lower pH (2.02, 1.33-3.09 per 0.1 decrease), hypoalbuminemia (2.02, 1.03-3.95 per 5 g/L decrease), and baseline renal dysfunction (1.33, 1.02-1.72 per 10 ml/min/1.73 m2 decrease), while PCI to lesion (0.11, 0.01-0.79) and bystander defibrillation (0.06, 0.004-0.80) were protective factors (all p < 0.05). CONCLUSIONS: Among patients with OHCA and shockable rhythm without STE, younger age, shorter time to ROSC and GCS >8 were associated with CA selection, while less effective resuscitation, greater burden of comorbidities and absence of treatable coronary lesion were key adverse prognostic predictors.
