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A nonarteriosclerotic cardiomyopathy is increasingly seen in obese patients. Seeking a rodent model, we studied cardiac histology, function, cardiomyocyte fatty acid uptake, and transporter gene expression in male C57BL/6J control mice and three obesity groups: similar mice fed a high-fat diet (HFD) and db/db and ob/ob mice. At sacrifice, all obesity groups had increased body and heart weights and fatty livers. By echocardiography, ejection fraction (EF) and fractional shortening (FS) of left ventricular diameter during systole were significantly reduced. The Vmax for saturable fatty acid uptake was increased and significantly correlated with cardiac triglycerides and insulin concentrations. Vmax also correlated with expression of genes for the cardiac fatty acid transporters Cd36 and Slc27a1. Genes for de novo fatty acid synthesis (Fasn, Scd1) were also upregulated. Ten oxidative phosphorylation pathway genes were downregulated, suggesting that a decrease in cardiomyocyte ATP synthesis might explain the decreased contractile function in obese hearts.

Alcohol, a major cause of human cardiomyopathy, decreases cardiac contractility in both animals and man. However, key features of alcohol-related human heart disease are not consistently reproduced in animal models. Accordingly, we studied cardiac histology, contractile function, cardiomyocyte long chain fatty acid (LCFA) uptake, and gene expression in male C57BL/6J mice consuming 0, 10, 14, or 18% ethanol in drinking water for 3 months. At sacrifice, all EtOH groups had mildly decreased body and increased heart weights, dose-dependent increases in cardiac triglycerides and a marked increase in cardiac fatty acid ethyl esters. [3H]-oleic acid uptake kinetics demonstrated increased facilitated cardiomyocyte LCFA uptake, associated with increased expression of genes encoding the LCFA transporters CD36 and Slc27a1 (FATP1) in EtOH-fed animals. Although SCD-1 expression was increased, lipidomic analysis did not indicate significantly increased de novo LCFA synthesis. By echocardiography, ejection fraction (EF) and the related fractional shortening (FS) of left ventricular diameter during systole were reduced and negatively correlated with cardiac triglycerides. Expression of myocardial PGC-1α and multiple downstream target genes in the oxidative phosphorylation pathway, including several in the electron transport and ATP synthase complexes of the inner mitochondrial membrane, were down-regulated. Cardiac ATP was correspondingly reduced. The data suggest that decreased expression of PGC-1α and its target genes result in decreased cardiac ATP levels, which may explain the decrease in myocardial contractile function caused by chronic EtOH intake. This model recapitulates important features of human alcoholic cardiomyopathy and illustrates a potentially important pathophysiologic link between cardiac lipid metabolism and function.

Direct measurement of multiple VC areas using 3D transesophageal echocardiography allows for assessing MR severity in patients with multiple jets, particularly for MR degrees greater than mild and in cases of more than 2 jets, for which geometric assumptions may be challenging.

Mild PHPT is associated with subclinical aortic valve calcification. PTH, but not serum calcium concentration, predicted aortic valve calcification. PTH was a more important predictor of aortic valve calcification than well-accepted cardiovascular risk factors.

Objectives: To clarify the value of cycle dependent variation of myocardial integrated backscatter (CV-IB) analysis, which non-invasively measures acoustic properties of the myocardium, for early detection of cardiac involvement in patients with sarcoidosis. Methods: The study population consisted of 22 consecutive patients with biopsy proven sarcoidosis who did not have any abnormal findings on conventional two dimensional echocardiogram. Cardiac sarcoidosis was diagnosed by radionuclide testing including thallium-201 scintigraphy, gallium-67 scintigraphy, and cardiac fluorine-18-deoxyglucose positron emission tomography. The magnitude and delay of the CV-IB were analysed in the basal mid septum and the basal mid posterior wall of the left ventricle of all patients. Results: The patients were divided into two groups: 8 patients with cardiac involvement and 14 patients without cardiac involvement. In the basal septum, a major reduction in the magnitude (mean (SD) 1.8 (4.4) v 6.6 (1.3) , p = 0.012) and an increase in the time delay (1.3 (0.5) v 1.0 (0.1), p = 0.038) of CV-IB were observed in patients with cardiac sarcoidosis even in the absence of two dimensional echocardiographic abnormalities. The sensitivity for detecting cardiac involvement was such that the magnitude of CV-IB in the basal septum discriminated 75% of patients with cardiac sarcoidosis from those with non-cardiac sarcoidosis, whereas two dimensional echocardiographic parameters did not discriminate between these two groups. Conclusions: The CV-IB is decreased in the basal septum in patients with cardiac sarcoidosis even in the absence of two dimensional echocardiographic abnormalities. Analysis of CV-IB may be a useful method to detect early myocardial involvement in patients with sarcoidosis.

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