Follow-up study of factors influencing prognosis of cardiac arrest patients after acute myocardial infarction

Abstract

Objective To assess the factors associated with the restoration of spontaneous circulation (ROSC) and 2-year survival prognosis in patients with cardiac arrest (CA) after acute myocardial infarction (AMI), and after ROSC, the effects of various factors on midian survival time and on 2-year survival. Methods In a registry study from January 2005 to January 2015, all consecutive AMI-induced CA patients treated with cardiopulmonary resuscitation (CPR) admitted to our hospital were enrolled. The survivors were followed-up for 2 years. Univariate analysis was applied to evaluate factors associated with rate of ROSC and 2-year survival. Multivariable logistic regression analysis was applied to evaluate statistically significant factors in the univariate analysis. Medians with inter-quartile ranges were used to describe 2-year survival time affected by various factors after ROSC. Kaplan-Meier survival curve analysis was used to evaluate the effect of factors on 2-year survival. Results A total of 254 cases with CA after AMI were enrolled, including 129 cases of ROSC and 71 cases of 2-year survival. Univariate analysis showed age≥70 years, CA occurred during 22:00-8:00, the duration time of CPR≥15 min and adrenaline dosage > 5 mg were unfavorable predictors of ROSC; while, left ventricular ejection fraction (LVEF)≥40% before CA, shockable rhythm and percutaneous coronary intervention (PCI) therapy were favorable predictors. Besides, age≥70 years, intubation during CPR, adrenaline dosage > 5 mg and cardiogenic shock were unfavorable predictors of 2-year survival; While, male, normal daily activity before CA and PCI treatment were favorable predictors. Multivariable analysis showed age, the duration of CPR, adrenaline dosage, LVEF before CA, the rhythm during CPR and PCI therapy were independent predictors of ROSC. Age and PCI therapy were independent predictors of 2-year survival. Among patients, the survival time was affected by various factors after ROSC, and the factors with minimum 25% and small median value were associated with cardiac rupture, cancer, adrenaline dosage > 5 mg and cardiogenic shock. The factor with maximum 25% value was PCI treatment (216 days). Kaplan-Meier survival analysis suggested that age≥70 years was an unfavorable factor of 2-years survival (Log-rank test, P=0.007); while, PCI treatment was a favorable factor (Log-rank test, P<0.01). PCI-related prognosis analysis showed that the effectiveness of PCI was related to the timing of PCI, the number of infarct-related artery and the difference in culprit lesion. Conclusions The age≥70 years was disadvantageous to both ROSC and 2-year survival. PCI treatment was favorable to both ROSC and 2-year survival. Key words: Acute myocardial infarction; Cardiac arrest; Cardiopulmonary resuscitation; Percutaneous coronary intervention; Return of spontaneous circulation; 2-year survival; Survival analysis