Older patients with myocardial infarction (MI) who present to the hospital with out-of-hospital cardiac arrest (OHCA) did not have a higher 1-year mortality rate or increased health care use rates compared with patients without OHCA.
OHCA in patients with MI can lead to high rates of in-hospital mortality, but little is known about the post-discharge mortality rates among the patients who survive. Therefore, the researchers set out to compare the 1-year mortality rates after hospital discharge and the composite 1-year morality and all-cause readmission rates among MI survivors with and without OHCA.
They selected 54 860 patients over 65 years of age with MI using linked Acute Coronary Treatment and Intervention Outcomes Network Registry-Get With the Guidelines and Medicare data. All patients had been discharged from 545 hospitals in the United States between April 2011 and December 2012.
“We found that older patients with MI with OHCA had an unexpectedly good prognosis once they were discharged from hospital to home or a skilled nursing facility, even though they had greater rates of in-hospital cardiogenic shock, HF [heart failure], cardiac arrest, major bleeding, and red blood cell transfusion compared with patients without OHCA, a finding consistent with previous reports,” the authors wrote.
After discharge, patients with OHCA (n=641) were more likely to be younger, male, and current smokers, but less likely to have diabetes, HF, or prior revascularization compared with patients without OHCA (n= 54 219). Patients with OHCA also more often presented with ST-segment elevation MI (63.2% vs 29.6%) and cardiogenic shock (29.0% vs 2.2%).
Among in-hospital MI survivors, OHCA was not linked to 1-year mortality after discharge (unadjusted 13.8% vs 15.8%; P=.17; adjusted hazard ratio [HR]: 0.89; 95% confidence interval [CI]: 0.68-1.15).
Interestingly, MI survivors with OHCA had lower unadjusted and adjusted risk of composite outcome of 1-year mortality or all-cause remission than the patients without OHCA (44.0% vs 50.0%; P=.03; adjusted HR: 0.84; 95% CI: 0.72-0.97).
“…because our data show that older MI survivors with OHCA have a good prognosis once they are discharged, ongoing efforts to organize pre-hospital and intra-hospital processes of care should continue with the goal of improving acute survival rates,” the authors wrote.
They also noted the recently implemented strategies that have effectively improved pre-hospital interventions and outcomes for patients with OHCA: public resuscitation training, automated external defibrillator networks, mobile telephone positioning systems to dispatch volunteers, and adherence to hospital care guidelines for resuscitation, including routine early cardiac catheterization consideration.
Fordyce CB, Wang TY, Chen AY, et al. Long-term post-discharge risks in older survivors of myocardial infarction with and without out-of-hospital-cardiac arrest. J Am Coll Cardiol. 2016;67(17):1981-1990. doi: 10.1016/j.jacc.2016.02.044.