Immediate changes of left ventricular function after total occlusion opening of artery rich in collaterals versus in artery without collaterals

Abstract

Background: For ischemic patients, left ventricular function is essential to their quality of life, and the major goal of coronary interventions is to keep the myocardium's blood supply productive. Thus, the complete cessation of blood flow to the myocardium for a prolonged duration is the obstacle to chronic total occlusion (CTO). Effective CTO coronary interventions improve the quality of life for the patient by improving LV systolic function, reducing angina, and increasing exercise capacity. Aim: This study aimed to compare the immediate changes that occur in the left ventricular systolic function in patients with CTO after successful revascularization in presence or absence of collateral circulation.
Subjects and methods: This was an analytical cross-sectional study that was conducted at the Military Hospitals (Air Force, Maadi and Kobri El Koba Hospitals). Patients were recruited from the Cardiology Department from January 2023 to December 2023. Two groups were included: Group 1 included forty patients with CTO in any coronary artery more than 2.5 mm in its diameter with presence of ipsilateral or contralateral collateral circulation based on coronary angiography. Group 2 included other forty patients with CTO in any coronary artery more than 2.5 mm in its diameter with no collateral circulation based on the coronary angiography. Trans- thoracic echocardiography was done for all patients including both conventional (M-mode and 2D) and tissue Doppler strain rate studies 24 hours before PCI and two weeks after successful CTO PCI with final TIMI III flow. Results: Strain rate statistically significantly improved in group 1 compared to group 2 in terms of the septal and inferior wall segments 2 weeks after CTO opening.
Conclusion: In CTO interventions, the presence of collateral circulation predicts immediate improvement in left ventricular systolic function as assessed by tissue Doppler intervention (TDI) using strain rate technique despite the lack of significant effect on conventional left ventricular systolic parameters as wall motion score index measurements.