This was a prospective cohort study that included 80 patients with their first acute STEMI who presented within 12 h after the onset of chest pain and referred for primary PCI in the period between December 2017 and November 2018.
Patients were excluded from the study if they had a previous history of ischemic heart disease (prior AMI, PCI, or coronary artery bypass graft), active infection, or malignancy. Patients on previous anti-thrombotic or anticoagulant medications and patients who received thrombolytic therapy before coronary angiography were also excluded from the study.
We applied the European Society of Cardiology guidelines for STEMI management in diagnosis [6]. A detailed history was taken, and a full clinical examination was done searching for CAD risk factors including age, sex, positive family history of premature CAD, body mass index, smoking, dyslipidemia, HTN, and DM.
Patients with DM were identified on admission as HbA1c ≥ 6.5% (48 mmol/mol) or fasting plasma glucose ≥ 7.0 mmol/l (126 mg/dl) or 2-h postprandial glucose ≥ 11.1 mmol/l (≥ 200 mg/dl) or those using either oral hypoglycemic agents or insulin treatment [7]. Dyslipidemia was defined as total cholesterol of at least 200 mg/dl or using anti-hyperlipidemic therapy on admission [8]. HTN was defined as office systolic blood pressure values ≥ 140 mmHg and/or diastolic pressure values ≥ 90 mmHg or using antihypertensive therapy on admission [9].
All patients received aspirin 300 mg and clopidogrel 600 mg (available P2Y12 inhibitor at our institute) before their transfer to the catheterization laboratory. Emergency coronary angiography was performed using the percutaneous femoral or radial approach. Heparin (100 U/kg) was administered in all patients during the primary PCI procedure [10].
The crossing of the occluded culprit artery was done using various guide wires, and pre-dilatation was performed via balloon angioplasty if necessary. Routine stenting using a drug-eluting stent was attempted directly or following balloon angioplasty. The usage of thrombus aspiration catheter and administration of tirofiban infusion were chosen according to the decision of the interventional cardiologist [11]. Thrombus grading was done using the TIMI thrombus scale grade [12].
The initial TIMI flow was assessed at the beginning of the procedure before wire crossing and the final TIMI flow immediately after the primary PCI using the TIMI flow grade classification [13]. The MBG was assessed visually on the angiogram and interpreted immediately after the primary coronary angioplasty procedure by the performing cardiologist: grade 0, no myocardial blush; grade 1, minimal myocardial blush; grade 2, moderate myocardial blush; and grade 3, normal myocardial blush [14].
Ejection fraction (EF) was measured within the first 48 h after primary PCI by the modified Simpson’s method using a (Vivid S5, General Electric Healthcare) echocardiography device.
We obtained peripheral venous samples on admission from all patients before the primary PCI then they were centrifuged early after collection, and extracted serum was stored at − 20 °C. We measured 25-hydroxy vitamin D concentrations (vitamin D) using the enzyme-linked immunosorbent assay (Calbiotech, 25(OH) Vitamin D ELISA).
According to serum vitamin D levels, study population was divided into 2 groups: group A, which included patients with abnormal vitamin D levels less than 30 ng/ml, and group B, which included patients with normal vitamin D levels equal to or more than 30 ng/ml.
Statistical analysis
We used version 20.0 of the Statistical Package for Social Sciences (SPSS Inc., Chicago, IL, USA) in the data analysis. Quantitative data was expressed as mean ± standard deviation. Qualitative data was expressed as frequency and percentage. Comparing two means was done using the independent-samples t test, the chi-square (χ2) test was used in comparing proportions between qualitative parameters, and correlation between 2 sets of variables was done using the Spearman correlation coefficient (r) test. The confidence interval was set to 95, and the accepted margin of error was set to 5%. So, the p value was considered significant as follows: probability (p value) < 0.05 was considered significant, and p value > 0.05 was considered non-significant.
