Reclassification of Heart Failure with Preserved Ejection Fraction Following Cardiac Sympathetic Nervous System Activation: A New Cutoff Value of 58%

Figures

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  Figure 1. (a) The delayed heart/mediastinum (H/M) ratio was significantly higher in patients with a left ventricular ejection fraction (LVEF) of ≥58% than in those with an LVEF of <58% (2.1 ± 0.3 vs. 1.7 ± 0.4, p = 0.004). (b) When divided into two groups using an LVEF of 50%, no significant differences were found in the delayed H/M ratio between the two groups (1.9 ± 0.4 vs. 1.8 ± 0.3, p = 0.17). These data were compared using an unpaired Student’s t-test.

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  Figure 2. (a) The washout rate (WR) was significantly lower in patients with a left ventricular ejection fraction (LVEF) of <58% compared to that of those with an LVEF of ≥58% (32.9 ± 12.6% vs. 45.1 ± 15.4%, p = 0.007). (b) No significant differences were found in the WR between patients with an LVEF of ≥50% and those with an LVEF of <50% (37.8 ± 15.7% vs. 44.6 ± 15.2%, p = 0.10). These data were compared using an unpaired Student’s t-test.

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  Figure 3. The ability of the delayed heart/mediastinum (H/M) ratio to identify LVEF of 58% or 50% was evaluated using a receiver operating characteristic (ROC) curve analysis, in which the area under the curve (AUC) and 95% confidence interval (CI) were calculated. (a) The ROC curve for the delayed H/M ratio for predicting a left ventricular ejection fraction (LVEF) of 58% was 0.75 (95% CI 0.61–0.89, p = 0.004). From this analysis, a delayed H/M ratio of 1.9 had a sensitivity and specificity of 80.0% and 72.9%, respectively, for predicting an LVEF of 58%. (b) The area under the ROC curve for delayed H/M ratio for predicting an LVEF of 50% was not significant (0.60; 95% CI 0.44–0.75, p = 0.21).

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  Figure 4. Comparison of the delayed heart/mediastinum ratio (H/M) and the washout rate (WR) among the three groups; LVEF ≥ 50% (n = 22), LVEF 40–50% (n = 9), and LVEF < 40% (n = 32). No significant differences were observed in the delayed H/M ratio (1.9 ± 0.4 vs. 1.8 ± 0.4 vs. 1.8 ± 0.3, respectively, p = 0.48 (a) or WR (37.8 ± 15.7% vs. 39.7 ± 19.2%, vs. 45.5 ± 14.3%, respectively, p = 0.22 (b) among the three groups. These data were compared using an analysis of variance (ANOVA) with Bonferroni adjustment.

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  Figure 5. For endpoint-free survival analysis, Kaplan–Meier curves were generated and compared using the log-rank test. Kaplan–Meier curves for all-cause mortality in patients with a left ventricular ejection fraction (LVEF) of ≥58% (a) and ≥50% (b). The survival rate was significantly higher in patients with an LVEF of ≥58% than in those with an LVEF of < 58%. No significant differences were found between patients with an LVEF of ≥50% and those with <50%. Kaplan–Meier curves for the combined endpoint of subsequent heart failure and all-cause mortality in patients with an LVEF of ≥58% (c) and ≥50% (d). No significant differences were found between patients with an LVEF of ≥58% and <58%, as well as between patients with an LVEF of ≥50% and <50%.