BACKGROUND The PRKAG2 cardiac syndrome is an inherited metabolic disease of the heart characterized by excessive myocardial glycogen deposition. The biochemical alterations associated with this condition remain controversial and have not previously been studied in affected humans. METHODS AND RESULTS Positron emission tomography (PET) imaging was used to quantitatively assess myocardial gluco...

BACKGROUND Around birth, myocardial substrate supply changes from carbohydrates before birth to primarily fatty acids after birth. Parallel to these changes, the myocardium is expected to switch from the use of primarily lactate before birth to fatty acids thereafter. However, myocardial lactate uptake and oxidation around birth has not been measured in vivo. METHODS AND RESULTS We measured m...

The effects in vivo of physiologic increases in insulin and amino acids on myocardial amino acid balance were evaluated in conscious dogs. Arterial and coronary sinus concentrations of amino acids and coronary blood flow were measured during a 30-min basal and a 100-min experimental period employing three protocols: euglycemic insulin clamp (plasma insulin equaled 70 +/- 11 microU/ml, n = 6); e...

• Since the report of Evans and Matsuoka ' a half century ago, it has been known that myocardial oxygen uptake increases in approximately a linear fashion with mean arterial pressure, but is affected only slightly by increases in cardiac output.' This paradox, that "pressure work" is much more costly than "volume work," complicated the analysis of the energetics of myocardial contraction. A con...

Technetium-99m-pyrophosphate (99mTc-PYP) has been used, in combination with thallium-201, to estimate the site and extent of myocardial infarcts. We report a case of acute myocardial infarction with severe coronary disease in which the distribution of 99mTc-PYP was extensive. A 78-year-old man presented with dyspnea, and a diagnosis of non-ST-segment elevation acute myocar...

Objective(s): Iodine-123 metaiodobenzylguanidine (123I-MIBG) myocardial scintigraphy has been used to evaluate cardiac sympathetic denervation in Lewy body disease (LBD), including Parkinson’s disease (PD) and dementia with Lewy bodies (DLB). The heart-tomediastinum ratio (H/M) in PD and DLB is significantly lower than that in Parkinson’s plus syndromes and Alzheimer’s disease. Although this ra...

Amyloidosis is characterized by an abnormal extracellular deposition of amyloid in different organs, where it usually causes some type of dysfunction. Its cause is unknown. Five different types of amyloidosis have been described according to the underlying disease; immunoglobulin amyloidosis, familial amyloidosis, senile systemic amyloidosis, secondary amyloidosis and hemodialysis-associa...

Article type: Original Article Introduction: Left ventricular ejection fraction (LVEF) is considered to be the single most important prognostic factor in patients with previous myocardial infarction. LVEF is not improved in all patients after coronary artery bypass grafting (CABG). This study aimed to assess the possibility of prediction of LVEF changes after CABG using myocardial perfusion gat...

UNLABELLED We investigated myocardial fatty acid metabolism in taxan-induced myocardial damage in patients with advanced lung cancer. PATIENTS AND METHODS Twenty-five patients with non-small-cell lung cancer were treated with taxan combined with carboplatin intravenously for three cycles. Myocardial SPECT imaging using 99mTc-methoxyisobutyl isonitrile (MIBI) and 123I-15-(p-iodophenyl)-3-(R,S)...

The myocardial potassium uptake during intracoronary isoproterenol stimulation was characterized in 12 anesthetized pigs. The beta-receptor subtype specificity and the effect of adenylate cyclase activation were determined. Potassium concentrations were continuously recorded by PVC-valinomycin minielectrodes in the left atrial cavity and in coronary sinus blood diverted through a shunt to the r...