Pilot study for left ventricular imaging phenotype of patients over 65 years old with heart failure and preserved ejection fraction: the high prevalence of amyloid cardiomyopathy

This study sought to phenotype patients over 65 years old with heart failure and preserved ejection fraction (HFpEF) using clinical available comprehensive cardiovascular imaging modalities. Forty-nine patients with HFpEF and without coronary artery disease underwent clinical evaluation, electrocardiography, echocardiography, cardiac magnetic resonance (CMR) and Tc-99m-3,3-diphosphono-1,2-propanodicarboxylic acid scintigraphy (Tc-99m-DPD). The mean population age was 76 +/- 8 years. Most of the patients (53 %) were NYHA class II. Mean NT-Pro-NBNP level was 1961 +/- 2372 pg/ml. CMR exhibited a hypertrophic cardiomyopathy or infiltrative pattern in 3 (6 %) and 15 (31 %) patients, respectively. In the latter subgroup, Tc-99m-DPD was suggestive of transthyretin-related cardiac amyloidosis for nine (18 %) patients, while AL amyloidosis was proven in five patients (10 %) by extracardiac (n = 3, 6 %) or endomyocardial (n = 2, 4 %) biopsies-one patient declined tissue biopsy. Compared to patients with unspecified cardiomyopathy (n = 31), patients with amyloid cardiomyopathy (n = 15 or n = 14/proven) had less hypertension, lower systolic blood pressure and higher NT-pro BNP level. Their electrocardiogram showed lowest QRS voltage and longer QRS duration. Left ventricular (LV) pattern was characterized by a more pronounced LV hypertrophy, a smaller ejection fraction and a decrease of global longitudinal strain associated with an increase of longitudinal strain apical-to-basal ratio. In patients over 65 years, HFpEF is a heterogeneous syndrome with at least a 29 % prevalence of amyloid cardiomyopathy. Combined CMR and Tc-99m-DPD are helpful imaging tools for accurate phenotyping of patients amenable to histopathological diagnosis or genetic testing, and should be considered for proper management of this population. Further longitudinal investigations are needed to better clarify these preliminary results.