Prophylactic Beta-Blocker Therapy in Patients Who Underwent Primary Percutaneous Coronary Intervention for ST-Elevation Myocardial Infarction With Preserved Left Ventricular Ejection Fraction: A Systematic Review and Meta-Analysis

Figures

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  Figure 1. PRISMA 2020 flow diagram for study selection The diagram illustrates the flow of information through the different phases of the systematic review. It outlines the number of records identified, included, and excluded, as well as the reasons for exclusion at each stage—from the initial database search yielding 187 articles to the final six studies included in the meta-analysis. HFpEF: Heart failure with preserved ejection fraction.

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  Figure 2. Risk of bias summary for randomized controlled trials This figure provides a study-by-study summary of the risk of bias assessment for the two included RCTs (Watanabe et al., 2018 [14], and Yndigegn et al., 2024 [5]), based on the Cochrane Risk of Bias-2 (RoB-2) tool. Each row represents an individual study, and each column corresponds to a specific bias domain. The color and symbol in each cell indicate the judgment for that study and domain: green (+) for low risk of bias, yellow for some concerns, and red (–) for high risk of bias.

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  Figure 3. Risk of bias graph for randomized controlled trials This graph visualizes the aggregated risk of bias judgments across the two included RCTs for each domain of the Cochrane RoB-2 tool. Each bar represents a bias domain, and the colored segments indicate the proportion of studies judged to be at low risk of bias (green), some concerns (yellow), or high risk of bias (red). The figure highlights that the primary sources of potential bias were related to performance bias and detection bias, stemming from the open-label design of the trials. RCT: Randomized controlled trial; RoB-2: Risk of Bias-2.

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  Figure 4. Forest plot of all-cause mortality This forest plot visualizes the meta-analysis of the primary outcome, all-cause mortality. Each square represents the relative risk (RR) from an individual study, with the horizontal line indicating the 95% confidence interval (CI). The size of the square is proportional to the study's weight in the analysis. The diamond represents the pooled RR estimate, which shows a statistically significant reduction in all-cause mortality with beta-blocker therapy (RR, 0.60; 95% CI, 0.43-0.85). The I² statistic indicates substantial heterogeneity between studies. BBL: Beta-blockers.

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  Figure 5. Forest plot of cardiovascular mortality (all studies) This forest plot shows the pooled analysis for the secondary outcome of cardiovascular mortality across all included study types. The diamond represents the overall relative risk (RR), which did not show a statistically significant difference between the beta-blocker and no-beta-blocker groups (RR, 0.62; 95% CI, 0.28-1.34). The I² statistic indicates high heterogeneity. BBL: Beta-blockers.

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  Figure 6. Forest plot of cardiovascular mortality (subgroup analysis by study design) This plot presents a subgroup analysis for cardiovascular mortality, separating randomized controlled trials (RCTs) and observational studies. The results show a trend toward benefit in observational studies (RR, 0.29; 95% CI, 0.08-1.01) but no effect in RCTs (RR, 1.16; 95% CI, 0.76-1.79). The test for subgroup differences indicates a significant discrepancy between the study types. BBL: Beta-blockers.

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  Figure 7. Forest plot of reinfarction This forest plot visualizes the meta-analysis for the secondary outcome of reinfarction. The pooled relative risk (RR), represented by the diamond, shows no significant difference between the beta-blocker and no beta-blocker groups (RR, 0.87; 95% CI, 0.71-1.07). BBL: Beta-blockers.

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  Figure 8. Forest plot of hospitalization for heart failure This plot shows the meta-analysis for hospitalization for heart failure from the two included randomized controlled trials (RCTs). The pooled relative risk (RR, 1.32; 95% CI, 0.60-2.89) indicates no significant difference between the groups. BBL: Beta-blockers.

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  Figure 9. Forest plot of hospitalization for stroke This plot shows the meta-analysis for hospitalization for stroke from the two included randomized controlled trials (RCTs). The pooled relative risk (RR, 1.03; 95% CI, 0.53-2.02) indicates no significant difference between the groups. BBL: Beta-blockers.