1University Medical Centre Maribor - Maribor - Slovenia
2University of Maribor, Medical faculty - Maribor - Slovenia
Background. After cardiac arrest (CA) complex post-resuscitation syndromes develope such as brain injury, global cardiac dysfunction, systemic ischemia/reperfusion injury, etc. Brain injury accounts for the majority of deaths, but severe acute post-CA heart failure – in particularly shock - affects more than two-thirds of OHCA patients. Mortality from post-CA shock and brain injury share similar risk factors, which are related to the quality of the rescue process. Shock after CA, requiring vasopressor support is consistently associated with an adverse outcome after CA and is the result of pre-existing cardiac pathology, ischemia/reperfusion injury with activated inflammatory cytokine and catecholamines, etc. Hemodynamic stabilization after CA aims to reverse the effects of myocardial dysfunction and to improve systemic perfusion.
Purpose. To evaluate the less clear association between acute heart failure and 30-day mortality of admitted OHCA patients.
Methods. We retrospectively included 110 OHCA patients, admitted in 2013 to 2016 (72.7% men, mean age 65.6±13,8 years, age = 65 years 72.7%) to the medical ICU. We registered their clinical and laboratory data, treatments, 30-day mortality and predictors of 30-day mortality.
Results. In admitted OHCA patients witnessed CA was observed in 71.8%, ventricular fibrillation or pulseless ventricular tachycardia (VF/VT) as the cause of OHCA in 63.6%, asystole in 35.5%, resuscitation =20 minutes in 21.8%, admission lactate = 6 mmol/L in 30%, acute coronary syndromes (ACS) in 55.5%, PCI in 40%, admission mechanical ventilation (MV) in 87.3%, in-hospital peak NT-proBNP = 400pmol/l in 23.6%, in-hospital acute heart failure 82.7% and shock in 75.5%, ischemic brain injury in 62.7% and acute kidney injury (AKI) in 32.7%. 30-day mortality of admitted OHCA patients was 48.2%. 30-day mortality in comparison to survival was associated significantly with age = 65 years (54.6% vs 29.8%, p=0.02), with asystole as the cause of CA (56.6% vs 15.8%, p<0.001), resuscitation = 20 minutes (32.1% vs 12.3%, p=0.017), admission MV (98.1% vs 77.1%, p=0.001) and lactate = 6 mmol/l (45.3% vs 15.8%, p=0.005), in-hospital acute heart failure (98.1% vs 68.4%, p<0.001), shock (84.9% vs 66.7%, p=0.029), AKI (47.2% vs 19.3%, p=0.002), brain injury (96.2% vs 31.6%, p<0.001), peak NT-proBNP = 400pmol/L (30.2% vs 17.5%, p=0.003), but significantly less likely with ACS (43.4% vs 66.7%, p=0.042), VF/VT as the cause of CA (43.4% vs 82.5%, p<0.001) and admission EF = 35% (24.5% vs 43.9%, p=0.031). Logistic regression (forward Wald) demonstrated that peak hospital NT-proBNP = 400pmol/l was most significant independent predictor of 30-day mortality (OR 29.8, 95% CI 2.377-372.762, p=0.009).
Conclusions. Acute heart failure was present in more than 80% of admitted OHCA patients – in particular in early non-survivors. Increased levels of NT-proBNP, reflecting acute heart failure, most significantly predicted 30-day mortality in admitted OHCA patients.