CAD: Acute Coronary Syndromes

1356597 - Sonothrombolysis in acute myocardial infarction: CMR findings and mid-term survival analysis

Thursday, January 26, 2023

1:00 PM – 2:00 PM

Location: Pacific Jewel

Presenting Author(s)

Carlos Eduardo E. Rochitte, MD, PhD

Associate professor of Cardiology
Heart Institute, University of São Paulo
Sao Paulo, Sao Paulo, Brazil

Primary Author(s)

AV

Andre Vaz, MD

Fellow in Cardiovascular Imaging
Heart Institute, University of São Paulo, Brazil

Co-Author(s)

MR

Max Reyes Barrenechea, MD

Fellow in Cardiovascular Imaging
Heart Institute, University of São Paulo, Brazil
WM

Wilson Mathias Júnior, PhD

Cardiologist
Heart Institute, University of São Paulo, Brazil
LA

Luciene Ferreira Azevedo, PhD

Coordinator
Heart Institute, University of São Paulo, Brazil
Id

Isabella Scavariello Zicari di Monte

Researcher
Heart Institute, University of São Paulo, Brazil

Background: Prospective randomized controlled trials have demonstrated improved recanalization rates, and reduced infarct and no-reflow sizes in acute ST-segment elevation myocardial infarction (STEMI) treated with sonothrombolysis (STB) added to Percutaneous Coronary Intervention (PCI) [1,2]. However, there is still a paucity of data regarding the behavior of myocardial strain evaluated by cardiovascular magnetic imaging (CMR), and the mid- and long-term outcome of patients who underwent this novel therapy. Therefore, the objectives were to compare feature tracking myocardial strain, and mid-term survival in patients with STEMI who underwent STB and PCI or PCI alone.

Methods: All patients from the MRUSMI (Microvascular Recovery with Ultrasound in Acute Myocardial Infarction) trial were included and randomly assigned to STB and PCI (50%) or PCI alone (50%). CMR was performed between 48 and 72h post-PCI. The primary endpoint was Major Adverse Cardiac Event (MACE included all-cause mortality, re-infarction, hospitalization due to heart failure, stroke and myocardial revascularization), and the secondary endpoint was left ventricular systolic dysfunction, defined as the most recent echocardiogram with a left ventricular ejection fraction (LVEF) < 50%.

Results: One hundred (100) patients were included (50 in the STB group and 50 in the control group), of which 85 were submitted to CMR (47 in the STB group and 38 in the control group). The patients were followed up for an average of 3.8 years (standard deviation of 2.2 years). During follow-up, there were 25 MACE (3 all-cause mortality, 11 re-infarctions, 3 hospitalizations due to heart failure, and 8 myocardial revascularizations) and 57 patients developed systolic dysfunction. No association was observed between MACE and STB (p = 0.188), nor CMR findings (p > 0.05). Figure 1 demonstrates the Kaplan-Meyer curves for MACE and treatment group. No association was observed between systolic dysfunction and STB (p = 0.645), however, a positive association was identified between systolic dysfunction and no reflow size (p = 0.006) and Global Circumferential Strain (p = 0.012). Cox regression results for MACE and systolic dysfunction are shown in Table 1. The best Global Circumferential Strain reference to predict mid-term systolic dysfunction according to Youden’s index was -13% (sensibility of 70% and specificity of 90%). Figure 2 depicts the cumulative incidence of systolic dysfunction in patients with Global Circumferential Strain inferior or superior to -13%.

Conclusion: In this group of patients with STEMI, the use of sonothrombolysis showed no association with MACE or systolic dysfunction at follow-up. Nonetheless, Global Circumferential Strain and no-reflow size predicted independently systolic dysfunction at mid-term follow-up. Further larger studies are warranted to evaluate the benefit of sonothrombolysis in STEMI.