Left ventricular fibrosis and hypertrophy are associated with mortality in heart failure with preserved ejection fraction

Abstract

Cardiac magnetic resonance (CMR) is emerging as an important tool in the assessment of heart failure with preserved ejection fraction (HFpEF). This study sought to investigate the prognostic value of multiparametric CMR, including left and right heart volumetric assessment, native T1-mapping and LGE in HFpEF. In this retrospective study, we identified patients with HFpEF who have undergone CMR. CMR protocol included: cines, native T1-mapping and late gadolinium enhancement (LGE). The mean follow-up period was 3.2 ± 2.4 years. We identified 86 patients with HFpEF who had CMR. Of the 86 patients (85% hypertensive; 61% males; 14% cardiac amyloidosis), 27 (31%) patients died during the follow up period. From all the CMR metrics, LV mass (area under curve [AUC] 0.66, SE 0.07, 95% CI 0.54-0.76, p = 0.02), LGE fibrosis (AUC 0.59, SE 0.15, 95% CI 0.41-0.75, p = 0.03) and native T1-values (AUC 0.76, SE 0.09, 95% CI 0.58-0.88, p < 0.01) were the strongest predictors of all-cause mortality. The optimum thresholds for these were: LV mass > 133.24 g (hazard ratio [HR] 1.58, 95% CI 1.1-2.2, p < 0.01); LGE-fibrosis > 34.86% (HR 1.77, 95% CI 1.1-2.8, p = 0.01) and native T1 > 1056.42 ms (HR 2.36, 95% CI 0.9-6.4, p = 0.07). In multivariate cox regression, CMR score model comprising these three variables independently predicted mortality in HFpEF when compared to NTproBNP (HR 4 vs HR 1.65). In non-amyloid HFpEF cases, only native T1 > 1056.42 ms demonstrated higher mortality (AUC 0.833, p < 0.01). In patients with HFpEF, multiparametric CMR aids prognostication. Our results show that left ventricular fibrosis and hypertrophy quantified by CMR are associated with all-cause mortality in patients with HFpEF.

Figure 1

Central illustration to demonstrate the value of multiparametric cardiovascular magnetic resonance imaging for informing prognosis. In this case example, there is evidence of concentric LV hypertrophy on cine imaging, the native T1 is significantly raised throughout, and there are focal areas of scar and fibrosis on LGE imaging.

Figure 2

Receiver operator characteristics (ROC) results for CMR functional parameters.

Figure 3

Kaplan–Meier survival analysis for variables associated with all-cause mortality. All cohort data is on the left-sided panel and the propensity matched cohort on the right-sided panel. In non-amyloid cohort, it was only native T1, which demonstrated prognostic significance.

Figure 4

Multiparametric CMR score in HFpEF. (A) Kaplan–Meier survival curves. (B) The relative difference of area under the curve (AUC) between the CMR model and the clinical characteristics. The CMR model demonstrated significant increase in area under the curve.