Reduced adipose tissue and increased myocardial uptake of dietary fatty acid is associated with reduced left ventricular ejection fraction in subjects with impaired glucose tolerance

Abstract Background Epicardial adipose tissue (EAT) locates anatomically and functionally contiguous to the myocardium and coronary arteries. It has been suggested that EAT accumulation is associated with cardiac remodeling and impaired cardiac performance. However, its role in left ventricular (LV) wall strain remains unclear. Purpose In this study, we aimed to clarify: whether EAT accumulation is related to global longitudinal (GLS), circumferential (CS) and radial strain (RS); and if so, in which extent or by which amount of EAT are required to deteriorate these strain. Methods Total 180 patients who had no obstructive coronary artery disease (CAD) on multi-detector computed tomography (MDCT) coronary angiography and normal left ventricular ejection fraction (LVEF) on conventional echocardiography were recruited. Cardiac CT was used to quantify EAT volume (EATV) and echocardiographic speckle tracking was used to measure the GLS, CS and RS. EATV index (EATV/Body surface area) was determined as: EAT volume, the sum of the EAT area from the base to the apex of the heart (cm3)/body surface area (m2). Adipose tissue was determined as the density range between −190 and −30 Hounsfield unit. According to the median value (68 cm3/m2), patients were divided into lower and higher EATV index two groups. Results In higher EATV index group (95±19 cm3/m2), mean age, body mass index (BMI), prevalence of hyperlipidemia and prevalence of CAD were larger than in lower EATV index group (48±14 cm3/m2). Male gender, hypertension, diabetes, smoking and LV mass index were comparable between two groups. Patients in higher EATV index had lower GLS than those in lower EATV index (−19.4±1.2% vs. −18.8±1.3%, p=0.002). However, there were no significant difference between two groups regarding to the CS and RS. Linear regression analysis showed that there was strong correlation between EATV index and GLS (R=0.216, p=0.004); whereas, both RS and CS were strongly associated with the interventricular septum thickness (RS: R=0.248, p=0.003; CS: R= −0.192, p=0.023) and relative wall thickness (RS: R=0.178, p=0.036; CS: R= −0.184, p=0.030) but not with EATV; on multiple regression analysis, EATV was a predictor of GLS independent of age, male gender, BMI, diabetes, hyperlipidemia, hypertension and CAD (Adjusted R2=0.238, p<0.001). Conclusion EATV is independently associated with GLS despite the preserved LVEF and lacking of obstructive CAD, and may play a significant role in estimating impaired longitudinal LV performance.

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P2725Transthyretin cardiac amyloidosis in heart failure with preserved ejection fraction: Imaging by Tc-99m bone scan

European Heart Journal ◽

10.1093/eurheartj/ehz748.1042 ◽

2019 ◽

Vol 40 (Supplement_1) ◽

Author(s):

S Fukuzawa ◽

S Okino ◽

H Ishiwaki ◽

Y Iwata ◽

T Uchiyama ◽

...

Keyword(s):

Heart Failure ◽

Left Ventricular Ejection Fraction ◽

Ejection Fraction ◽

Bone Scan ◽

Left Ventricular ◽

Ventricular Ejection ◽

Left Ventricular Ejection ◽

Myocardial Uptake ◽

Preserved Ejection Fraction ◽

Ventricular Ejection Fraction

Abstract Background Heart failure with preserved ejection fraction (HFpEF) is a heterogeneous clinical syndrome with multiple underlying causes. Transthyretin amyloidosis (ATTR) is an underdiagnosed cause of HFpEF. Extraosseous uptake, in particular, myocardial uptake, was observed in a number of ATTR patients examined with the bone scan tracers. Objectives We sought to determine the prevalence of ATTR as detected by the bone scan among the patients admitted due to HFpEF. Methods We screened all consecutive patients ≥60 years old admitted due to HFpEF (left ventricular ejection fraction ≥50%). All eligible patients were offered an echocardiogram and a bone scan (a 99mTc-DPD/MDP/HMDP scintigraphy). Echocardiographic and clinical variables were gathered in all the subjects. The intensity of the myocardial uptake was graded according to a visual scale ranging from 0 to 3 points, in which the absence of uptake was assigned a score of 0 points; uptake less than that of bone (referred to as the adjacent rib), 1 point; uptake similar to that of bone, 2 points; and uptake greater than that of bone, 3 points. The distribution of the uptake in myocardium was defined as focal uptake, diffuse uptake, uptake in a ventricular wall segment, diffuse ventricular uptake, or diffuse biventricular uptake. Results The study included 62 HFpEF patients (52% women, 73±9 years). The bone scintigraphic analysis revealed relatively intense myocardial uptake in 7 of 62 patients (11.2%). 7 patients had intense Tc-99m uptake (score of 2–3) in the cardiac region, showing deposition in both right and left ventricles in every case. Patients with amyloid deposition were older (78±6 vs. 70±12 years, p<0.05), had a lower systolic blood pressure (118±23 vs. 148±28 mmHg, p<0.05), and left ventricular ejection fraction (52±11 vs. 58±6%, p<0.05). Both groups had at least moderate left ventricular hypertrophy and abnormal global longitudinal strain with no significant difference between groups. In 6 all the cases, the final diagnosis of amyloidosis was based on the results of abdominal fat aspiration biopsy. Conclusion ATTR is an underdiagnosed disease that accounts for a significant number (11.2%) of HFpEF cases. These findings create an opportunity for further investigation in the targeted therapy of patients with HFpEF.

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