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Objectives The purpose of this study was to determine whether patients with idiopathic dilated cardiomyopathy (IDCM) exhibit alterations in myocardial fatty acid and glucose metabolism. Background Alterations in myocardial metabolism have been implicated in the pathogenesis of heart failure (HF); however, studies of myocardial metabolic function in human HF have yielded conflicting results. Animal models of HF have shown a downregulation of the expression of enzymes of fatty acid beta-oxidation that recapitulates the fetal energy metabolic program, in which fatty acid metabolism is decreased and glucose metabolism is increased. Methods Seven patients with IDCM (mean left ventricular ejection fraction 27 ± 8%) and 12 normal controls underwent positron emission tomography for measurements of myocardial blood flow (MBF), myocardial oxygen consumption (MVO2), myocardial glucose utilization (MGU), myocardial fatty acid utilization (MFAU) and myocardial fatty acid oxidation (MFAO). Results The systolic and diastolic blood pressures, plasma substrates and insulin levels, MBF and MVO2, were similar between groups. The rates of MFAU and MFAO were significantly lower in IDCM than in the normal control group (MFAU: 134 ± 44 vs. 213 ± 49 nmol/g/min, p = 0.003; and MFAO: 113 ± 50 vs. 205 ± 49 nmol/g/min, p = 0.001) and the rates of MGU were significantly higher in IDCM than the normal control group (MGU: 247 ± 63 vs. 125 ± 64 nmol/g/min, p Conclusions Patients with IDCM exhibit alterations in myocardial metabolism characterized by decreased fatty acid metabolism and increased myocardial glucose metabolism, a pattern similar to that shown in animal models of HF. Whether alterations in myocardial metabolism constitute an adaptive response or mediate the development of HF remains to be determined.

Acute myocardial infarction during pregnancy or the postpartum period is rare. We report a case of a 40-year-old postpartum woman who developed ST-elevation myocardial infarction due to severe diffuse coronary vasospasm. To our knowledge, this is the first case of angiographically evidenced coronary vasospasm in a postpartum woman, in the absence of vasoconstrictive medications.

Our objective was to determine the frequency and predictive factors for cardiac-related emergency department (ED) encounters within 30 days after percutaneous coronary intervention (PCI). The data source was an electronic database of 2,731 patients who had PCI from 2002 to 2004. Almost all underwent stent placement. Risk factors for returning to the ED were identified from clinical, anatomic, and demographic candidate variables using multivariate logistic regression. Approximately 9% of the cohort (255 of 2,731 patients) returned to the ED for cardiac reasons within 30 days, peaking around 3 days. ED visits were more likely in those whose index PCI was emergent or urgent (odds ratio [OR] 2.0, 95% confidence interval [CI] 1.3 to 3.0), in women (OR 1.9, 95% CI 1.5 to 2.5), and in those who had previous encounters with the ED or hospital (OR 1.7, 95% CI 1.5 to 2.0). Patients receiving stents were somewhat less likely to return (OR 0.7, 95% CI 0.5 to 1.0). In conclusion, the clinical courses of the 255 returning patients were generally benign, but 12% had a subsequent myocardial infarction or repeat PCI within 30 days of the ED encounter.

Because severe aortic insufficiency in the setting of preserved left ventricular function is often associated with a long asymptomatic period and unpredictable course on medical therapy, sensitive indices of left ventricular systolic performance are necessary for the optimal direction of therapeutic intervention. Because myocardial wall stress is closely related to both pathologic cardiac remodeling and ultimately to left ventricular decompensation, an accurate description of regional wall stress distribution may improve our ability to clinically manage these patients appropriately. The objectives of this study were (1) to define sensitive, noninvasive indices of left ventricular systolic performance to assist the clinician in the serial evaluation and early detection of increased left ventricular wall stress and, therefore, inadequate left ventricular remodeling and subsequent myocardial decompensation of patients with aortic insufficiency, and (2) to quantify differences in instantaneous global and regional end-systolic wall stress between normal subjects and patients.Magnetic resonance imaging was performed on 23 normal volunteers and 19 patients with aortic insufficiency and normal systolic function (ejection fraction, 57% +/- 6%). Finite-element analysis was used to estimate global and regional end-systolic stress.End-systolic stress was significantly higher in the patient group globally (154,700 +/- 31,711 versus 96,781 +/- 23,185 dyne/cm(2); p0.001) and regionally (p0.001 in all segments) despite normal systolic function and similar end-systolic pressures.End-systolic stress as determined by magnetic resonance imaging and finite-element analysis may have considerable potential as a noninvasive, clinically applicable index of regional left ventricular function that may help in the serial evaluation, optimal management, and early identification of left ventricular decompensation in patients with aortic insufficiency.