Value of Cardiac Magnetic Resonance Imaging in Assessment of the Myocardial Reperfusion after Primary Percutaneous Coronary Intervention with or without Thrombus Aspiration in Patients with ST-Elevation Myocardial Infarction with High Thrombus Burden

Abstract

Abstract Background Primary percutaneous coronary intervention (PCI) is effective in opening the infarct related artery in patients with myocardial infarction with ST-segment elevation. However, the embolization of atherothrombotic debris induces microvascular obstruction and diminishes myocardial reperfusion. Objective The study aims to evaluate the efficacy and safety of the manual thrombus aspiration during primary PCI for the acute ST-elevation myocardial infarction (STEMI) patients with high thrombus burden. Patients and Methods The current study was prospective cohort study which was conducted on 100 patients presenting to cardiology department in Ain Shams University hospitals with STEMI in the first 12 hours of presentation, comparing two group (50 patients in each group): the thrombus aspiration group(group A) who underwent manual thrombus aspiration before the provisional stenting and the conventional PCI group (group B) who underwent provisional stenting using standard technique without thrombus aspiration.). every patient is assigned to a particular group based on the operator’s preference. The blood flow of the culprit coronary artery in the thrombolysis in myocardial infarction (TIMI) and the myocardial blush grade(MBG) was recorded immediately after the emergency PCI operation in each group, then an echocardiogram was performed to determine the left ventricular dimensions and ejection fraction within in 1 week after the operation, cardiac MRI was performed 3 months after the operation to determine the left ventricular dimensions, ejection fraction, stroke volume and size of infarction and finally the data on major adverse cardiovascular events (MACE) during the 6 months of postoperative follow-up were collected. Results There were no statistically significant differences between the two groups in terms of the demographic data, the cardiovascular risk factors, the vital data at the time of the hospital admission, the Killip class and the pain to door. The postoperative final TIMI flow was TIMI III flow in 46 patients (92%) of the thrombus aspiration group vs 34 patients (68%) in the conventional PCI group with P- value = 0.003 (statically highly significant). The final MBG was grade III in 40 patients (80%) of the thrombus aspiration group vs 30 patients (60 %) in the conventional PCI group, grade II in 10 patients (20 %) vs 16 patients (32%) and grade 0 only in 4 patients (4 %) in the conventional PCI group with P- value = 0.033 (statically significant). The post operative ECHO showed smaller Left ventricular dimensions with higher Left ventricular systolic and diastolic function in the thrombus aspiration group than the conventional PCI group with p value = 0.000 (statically highly significant). The postoperative cardiac MRI showed smaller Left ventricular end -systolic and end -diastolic volumes index with higher Left ventricular systolic function and Left ventricular Stroke volume index in the thrombus aspiration group than the conventional PCI group with p value = 0.000 (statically highly significant). Moreover, the postoperative cardiac MRI showed smaller LV Size of infarction (LV myocardia scar) in the thrombus aspiration group than the conventional PCI group with p value = 0.000 (statically highly significant).finally, there was a significant reduced rate of cardiovascular death and major adverse cardiovascular events (MACE) with no difference regarding the rate of the cerebrovascular stroke within 6 months post procedure in the thrombus aspiration group compared to the conventional PCI group with p value = 0.027 (statically significant).