Evaluation of left ventricular ejection fraction in non-ST-segment elevation acute coronary syndromes and its relationship to treatment.

BACKGROUND

In-hospital assessment of left ventricular ejection fraction (LVEF) in non-ST-segment elevation acute coronary syndrome (NSTE-ACS) is emphasized in current practice guidelines. There are limited data regarding the evaluation of LVEF and clinical characteristics and in-hospital management in the "real world."

METHODS

Registries including the Canadian Acute Coronary Syndrome (ACS) I and II, Global Registry of Acute Coronary Events (main GRACE/expanded GRACE(2)), and Canadian Registry of Acute Coronary Events (CANRACE) enrolled 13,703 NSTE-ACS patients across Canada between 1999 and 2008. Patients were stratified by in-hospital LVEF measurement, and LVEF was categorized as normal, mildly, or moderately to severely impaired. We compared clinical characteristics, cardiac procedures, and clinical outcomes across these groups. Multivariable logistic regression identified factors independently associated with the assessment of LVEF.

RESULTS

Overall, 8,116 patients (59.2%) had LVEF measurement, and of the 7,667 patients with available LVEF data, 4,470 (58.3%) had normal, 1,916 (25%) mildly impaired, and 1,281 (16.7%) moderately to severely impaired LVEF. Patients with LVEF assessment more frequently (all P < .001) underwent cardiac catheterization, percutaneous coronary intervention or coronary bypass surgery, and had higher (both P < .001) rates of myocardial (re) infarction and heart failure. In-hospital reinfarction, higher Killip class, abnormal biomarker, hospital stay >10 days, and on-site cardiac catheterization facility were independently associated with LVEF assessment. Despite increasing LVEF assessment over time (P for trend < .001), 31.2% of patients in the most recent registry (2008) had no in-hospital LVEF assessment.

CONCLUSIONS

In-hospital LVEF assessment is not performed in many NSTE-ACS patients. The LVEF assessment, associated with increased use of evidence-based therapies and invasive cardiac procedures, was obtained more frequently in patients with myocardial (re) infarction, heart failure on presentation, and prolonged hospital stay.