Resuscitated cardiac arrest and prognosis following myocardial infarction

OBJECTIVES: To determine whether resuscitated cardiac arrest (CA) complicating ST elevation myocardial infarction (STEMI) impacts outcome, particularly in patients surviving to discharge.

BACKGROUND: Resuscitated CA complicating STEMI is associated with increased inpatient mortality. The impact on later prognosis is unclear.

METHODS: We analysed data from the UK Myocardial Ischaemia National Audit Project for STEMI patients admitted during January 2008-March 2010. We used survival analyses to assess the independent impact of resuscitated CA during the index episode on inhospital, 30 days, 1 year and medium term all-cause mortality.

RESULTS: Of 48 749 STEMI patients, 5308 (10.9%) were recorded as having a CA. Of these, 1557 (29.3%) died on the day of CA. In survivors, after covariate adjustment, resuscitated CA was associated with increased risk of death during the index admission (HR 4.05 (3.69 to 4.45) p<0.001). In patients surviving to discharge, a history of resuscitated CA was associated with increased risk of death to 30 days (HR 1.53 (1.18 to 2.00), p<0.001). However, beyond 30 days, resuscitated CA was not associated with increased mortality risk (1-year HR 0.95 (0.79 to 1.14, p=0.596); 3.5 years HR 0.90 (0.78 to 1.04), p=0.144). The influence of resuscitated CA on inhospital or 30-day mortality was similar whether CA occurred before or after hospital admission. Where the resuscitated CA rhythm was asystole, inhospital mortality was higher compared with ventricular arrhythmia (p<0.001) or pulseless electrical activity (p=0.011). Late resuscitated CA (occurring after the day of index STEMI) was associated with higher 30-day postdischarge mortality compared with early resuscitated CA (p=0.023).

CONCLUSIONS: STEMI complicated by resuscitated CA merits careful monitoring in the early period postevent. In contemporary practice, there is no impact of resuscitated CA on longer-term prognosis.