부산대학교 도서관

Introduction: Preclinical studies in ST elevation myocardial infarction (STEMI) indicate that high mechanical index impulses guided with transthoracic diagnostic ultrasound associated with intravenously administered microbubbles results in the dissolution of the thrombus (sonothrombolysis), improving coronary microcirculation and epicardial coronary recanalization rate.Hypothesis: Left atrial (LA) echocardiographic parameters are compromised in STEMI and can be accurately measured by two-dimensional echocardiography. To study the effect of sonotrombolysis on the LA pressure and volume we propose our study.Methods: A total of 100 patients were randomized, 50 for the control group and 50 for the therapy group. Echocardiographic analysis of LA pressure and volume were performed immediately before and after percutaneous coronary intervention (PCI), 72 hours, 1 month and 6 months of follow-up. LA pressure was classified in normal or elevated, depending on the grade of left ventricular diastolic disfunction (DD): normal diastolic function and DD grade 1 have normal LA pressure, and DD grades 2 and 3 have elevated LA pressure, according to the American and European guideline. LA volume was evaluated by Simpson method and indexed to the body surface area.Results: The LA pressure and volume had lower values in the therapy group after 6 months of PCI. The comparison of LA pressure between the therapy and control groups respectively was: before PCI (72% vs. 70% normal; 28% vs. 30% elevated; p=0.826), after PCI (68% vs. 65% normal; 32% vs. 35% elevated; p=0.777), 72 hours (75% vs. 62% normal; 25% vs. 38% elevated; p=0.147), 1 month (68% vs. 52% normal; 32% vs. 48% elevated; p=0.123) and 6 months (84% vs. 64% normal; 16% vs. 36% elevated; p=0.035). The comparison of LA volumes between the therapy and control groups respectively was: before PCI (19.0±6.2 vs. 22.4±9.8 ml/m; p=0.061), after PCI (22.8±7.9 vs. 24.4±12.1 ml/m; p=0.469), 72 hours (25.9±8.5 vs. 26.4±12.7 ml/m; p=0.815), 1 month (27.2±8.3 vs. 29.1±13.1 ml/m; p=0.410) and 6 months (26.7±7.5 vs. 33.1±14.9 ml/m; p=0.013).Conclusions: The use of sonothrombolysis as adjuvant therapy in STEMI patients results in better values of LA pressure and volume, demonstrating the benefit of using this new therapy.