Assessment of right ventricular function in patients presenting with inferior ST segment elevation myocardial infarction and right ventricular infarction undergoing primary percutaneous intervention by different echocardiographic modalities in correlation with angiographic findings

Background Patients with inferior wall myocardial infarction who have right ventricular (RV) involvement appear to have a worse prognosis than those without RV involvement; infarcted RV tissue fails to offer a sufficient preload which is essential for adequate LV performance. Thus, assessment of RV function is an important step in dealing with patients presenting with inferior wall myocardial infarction that will help in adopting a proper management plan. Objective To assess the correlation between RV function and angiographic findings in patients presenting with inferior wall myocardial infarction associated with RV infarction undergoing primary percutaneous coronary intervention. Patients and Methods Study included 60 patients who presented to Ain shams university hospitals by inferior wall ST segment elevation myocardial infarction associated with RV infarction during the period from February 2019 to August 2019.All patients were subjected to history taking, clinical examination, ECG recording then primary percutaneous coronary intervention. Echocardiographic assessment was done to all patients within 48 hours of admission. Results Study included 60 patients, 43 males (71.7%) and 17 females (28.3%), with mean age of 56.73 ± 9.94 years. Commonest Infarction related Artery (IRA) associated with impaired RV function was proximal RCA (p-value: 0.003). In 23 patients (38.3%) heavy thrombus burden was found while in the other 37 patients (61.7%) there was no evidence of heavy thrombus burden. Regarding post procedural TIMI flow grade: 1 patient (1.7%) had final TIMI I flow, 9 patients (15.0%) had final TIMI II flow and 50 patients (83.3%) had final TIMI III flow. There was statistically significant relationship between RV function assessed through measuring RV free wall strain and both of thrombus burden and final TIMI flow grade. Abnormal RV function was more commonly associated with heavy thrombus burden (p-value:0.023) and less than TIMI III flow after angioplasty (p-value:0.011).RV free wall systolic strain assessment had highest accuracy (75%) in detection of proximal RCA occlusion compared to other parameters including TAPSE, S’ and FAC. Conclusion Impaired RV function in patients presenting with RV infarction can be predicted by different angiographic findings. Proximal RCA total occlusion being commonest IRA associated with impaired RV function. Also, presence of heavy thrombus burden and less than TIMI III flow after angioplasty are associated with increased risk of impaired RV function. RV free wall strain measured by 2D-speckle tracking echocardiography has highest accuracy in detection of proximal RCA occlusion compared to other echocardiographic indices including TAPSE, S’ and FAC.