Dr. Risk Stratification and Clinical Eligibility of Invasive vs. Noninvasive Strategy in the Management of Non-ST Elevation Acute Coronary Syndrome Patients Admitted to Hawler Teaching Hospital

Abstract

Background and objectives:The term acute coronary syndrome (ACS) is a range of acute myocardial ischemic states including unstable angina (UA), non-ST segment (NSTE), and ST-segment elevation myocardial infarction (STEMI). It is required to identify the cardiovascular events risk in those patients in order to select the beneficial therapeutic strategy during the first hours of presentation. The aim of the present study is to stratify the cardiac event risk and to determine the clinical eligibility of invasive vs. noninvasive therapeutic strategy in patients presented with UA and NSEMI as defined as NSTE-ACS. Methods:In the current observational cross-sectional study, 100 consecutive patients who visited the emergency department and admitted to coronary care unit diagnosed as NSTE-ACS were recruited. Their medical and clinical information were obtained from the patient and medical records. The cardiac event risk was estimated according to the GRACE risk score (Global Registry of Acute Coronary Events) and the TIMI risk score (Thrombolysis in Myocardial Infarction). The clinical eligibility of invasive vs. noninvasive (Ischemia-guided) therapeutic strategy was determined according to the latest AHA/ACC guideline for the management of patients with NSTE-ACS in 2014. Results:Of patients presented with NSTE-ACS who underwent both therapeutic strategies most of them were males (71.0%). The mean ± S.D. was 60-62 years for age. The mean ± S.D. of body mass index (BMI), chest pain duration, systolic blood pressure and heart rate were comparable in two groups. In terms of clinical characteristics hypertension (72.0%), current smoking (56.0%), dyslipidemia (48.0%), and past history of coronary artery disease (CAD) (44.0%) were the most prevalent. Patients who underwent invasive strategy had significantly more ST-depression (75.6%) as compared to those who underwent non-invasive strategy (55.9%), P=0.044. However, non-invasive group had significantly more T-wave inversion, (59.3% vs. 34.1%; P=0.013). The studied groups showed no statistically significant difference in risk of mortality according to GRACE risk score (P=0.505), TIMI risk score (P=0.057), and Killip class (P=0.252). However, the majority of non-invasive group had low risk (67.8%) while, the invasive group more common to be at intermediate risk (29.3%) for 6-month mortality. There was no statistically significant predictor of two therapeutic strategies according to the patients characteristics and risk stratification (p>0.05).