Impact of Cardio-Selective Beta-Blockers on Infarct Size After Acute Myocardial Infarction

Aristotle University Of Thessaloniki100 enrolled

Overview

Introduction: The effect of intravenous beta-blockers on the extent of the necrotic area, after primary percutaneous transluminal coronary angioplasty (PTCA), for acute myocardial infarction is not well established. Purpose: The present study aims to investigate, whether the early intravenous administration of landiolol, a highly cardioselective b-blocker, reduces the extent of the necrotic area after ST-elevation myocardial infarction (STEMI). Methods: This prospective observational cohort study will enroll patients presenting with STEMI, who undergo primary PCI and receive either intravenous landiolol or standard oral β-blocker therapy, in accordance with current European Society of Cardiology (ESC) guidelines. Eligibility will be determined by predefined inclusion and exclusion criteria. Treatment selection will be based solely on the clinical judgment of the attending cardiologist, without randomization. Results: Final infarct size will be quantified by cardiac magnetic resonance imaging (CMR) performed at least three months after the STEMI to minimize edema-related overestimation. Myocardial function will be assessed during hospitalization using transthoracic echocardiography, including measurement of global longitudinal strain (GLS). Additional data will include serial high-sensitivity troponin and creatine phosphokinase (CPK) measurements, 24-hour continuous electrocardiographic monitoring for arrhythmia burden, and predefined safety outcomes collected throughout hospitalization.

Study Type

OBSERVATIONAL

Enrollment

100

Conditions

STEMI

Eligibility

Sex: ALLMin age: 18 YearsMax age: 80 Years

Medical Language ↔ Plain English

Inclusion Criteria: * Age between 18 and 80 years * Patients with electrocardiogram showing ST-segment elevation ≥2 mm in 2 or more contiguous leads for more than 30 minutes * Estimated time from symptom onset to reperfusion ≤12 hours * Patients scheduled to undergo primary angioplasty * Patients who have signed a consent form Exclusion Criteria: * Patients receiving chronic medication with beta-adrenergic blockers * Patients with a previous myocardial infarction * Persistent systolic blood pressure \<90 mmHg * Persistent heart rate \<55 beats per minute * Patients with Killip class III (acute pulmonary edema) or IV (cardiogenic shock) on initial examination * 12-lead electrocardiogram with PR interval \>200 milliseconds * 12-lead electrocardiogram showing second- or third-degree atrioventricular block * Bronchospasm requiring bronchodilator treatment * Possible pregnancy or postpartum period * Inability or refusal to sign the consent form

Outcomes

Primary Outcomes

Infarct Size (CMR)

This measurement represents one of the two co-primary outcomes of the study. Infarct size will be quantified by cardiac magnetic resonance imaging (CMR) and expressed in grams. CMR will be performed at least 3 months after the myocardial infarction to minimize the influence of myocardial edema.

Time frame: CMR will be done at least 3months after the myocardial infarction.

Global Longitudinal Strain (GLS)

This measurement represents one of the two co-primary outcomes of the study. Left ventricular global longitudinal strain will be assessed by transthoracic echocardiography during hospitalization to evaluate myocardial systolic function.

Time frame: Within the first 5 days after acute myocardial infarction.

Secondary Outcomes

Arrhythmia burden

Arrhythmia burden will be quantified from continuous telemetry monitoring during the first 24 hours after PCI. The arrhythmia burden will be expressed as a composite index integrating the following components obtained from the same monitoring period: * frequency of non-sustained ventricular tachycardia (NSVT) episodes (≥3 consecutive ventricular beats lasting \<30 seconds), * frequency of ventricular tachycardia (VT) episodes (≥3 consecutive ventricular beats lasting ≥30 seconds), * cumulative duration (in seconds) of all NSVT/VT episodes, and * total number of ventricular ectopic beats recorded during NSVT/VT events. All components will be analyzed collectively as quantitative descriptors of the overall arrhythmia burden.

Time frame: First 24 hours after percutaneous coronary intervention

Biomarkers of myocardial injury - Peak hs-Troponin I (ng/mL)

Serial measurements of hs-troponin concentrations will be performed. Hs-troponin will be measured in ng/ml. Reported summary measure will include the peak value from the scheduled samples. Samples are obtained as part of routine clinical care and analyzed by the site laboratory.

Time frame: At the diagnosis of STEMI, and subsequently at 1 hour, 24 hours, 48 hours, and 72 hours.

Safety Outcome - Number of participants with Cardiogenic shock

Number of participants who develop cardiogenic shock during hospitalization, defined as sustained hypotension accompanied by clinical or laboratory evidence of end-organ hypoperfusion and requiring initiation of inotropic support.