The metabolic syndrome and cardiovascular disease: Part I.

The metabolic syndrome is a constellation of metabolic risk factors and physical conditions that are accompanied by an enhanced propensity toward the development of type 2 diabetes, atherosclerosis, and cardiovascular disease. It presents a combination of atherosclerosis risk including atherogenic dyslipidemia, hypertension, elevated plasma glucose, hypercoagulability, and a proinflammatory state. The 2 major underlying risk factors for the metabolic syndrome are obesity and insulin resistance. Exacerbating factors are physical inactivity, advancing age, and endocrine and genetic factors. Associated hyperinsulinemia, hyperglycemia, and elevated adipokine levels (adipose cytokines) lead to vascular endothelial dysfunction, an abnormal lipid profile, hypertension, and vascular inflammation, all of which promote the development of atherosclerotic cardiovascular disease. In this 2-part series, the authors present an up-to-date and detailed systematic review of the literature on this important topic.

Effect of echocardiographic contrast on velocity vector imaging myocardial tracking.

BACKGROUND: Two-dimensional speckle tracking is an evolving ultrasound technology that allows objective evaluation of left ventricular function. The effect of echocardiographic contrast with 2-dimensional speckle tracking image processing is poorly defined. METHODS: A total of 11 patients undergoing clinically indicated transthoracic echocardiography who also required echocardiographic contrast for left ventricular endocardial border enhancement were prospectively studied. Offline velocity vector imaging analysis was performed to calculate global and regional longitudinal strain from the apical 4-chamber view while corresponding circumferential strain was obtained from the parasternal short-axis view at the papillary muscle level. Images were isochronally normalized and the systolic phase was studied precontrast and postcontrast opacification. RESULTS: Intraclass correlation coefficients were high for global circumferential strain in the short-axis view (0.77) and global longitudinal strain in the apical 4-chamber view (0.87) precontrast and postcontrast. Significant regional variability was present, more pronounced in the apical 4-chamber view (intraclass correlation coefficient 0.24-0.64) versus short-axis view (intraclass correlation coefficient 0.64-0.68). CONCLUSIONS: Velocity vector imaging is able to quantify global and regional strain with and without contrast. There is, however, wide interindividual variability in regional strain quantification with and without contrast, potentially limiting the clinical applicability.

Three methods for evaluation of left atrial volume.

AIM: To compare and contrast 3 different echocardiographic methods used to measure left atrial (LA) volume: biplane area length (AL), biplane modified Simpson (SIMP), and prolate ellipse (PE) methods. METHODS AND RESULTS: A review of consecutive patients who presented to our outpatient echocardiography laboratory for a resting transthoracic study between April 2006 and May 2006 was performed. Echocardiograms were reexamined and LA volume measured using the AL, SIMP, and PE methods. Of 102 consecutive patients evaluated, 97 had a measure of LA volume using all 3 methods. A significant difference in the measurement of mean +/- SD LA volume was noted among the 3 different methods: 37 +/- 16 mL/m(2) for AL, 34 +/- 14 mL/m(2) for SIMP, and 27 +/- 12 mL/m(2) for PE. The PE method yielded routinely smaller values compared with either the AL or SIMP method (P < 0.001). Differences increased with increased LA volume. The SIMP method derived consistently smaller (<5 mL/m(2)) values than those of the AL method, consistent across the full range of LA volumes. CONCLUSION: Significant differences exist among these 3 commonly used methods for measuring LA volume. Standardization of the measurement of LA volume is recommended.

Ventricular fibrillation in late recovery after dobutamine stress echocardiography.

A 62-year-old man with multiple cardiac risk factors, including diabetes mellitus type II, treated hypertension, and hyperlipidemia, had a dobutamine stress echocardiogram performed as part of a preoperative evaluation. At peak stress the patient developed an apical regional wall motion abnormality. Approximately 12 minutes into the recovery period, the patient developed ventricular tachycardia that degenerated into ventricular fibrillation. He was successfully resuscitated and underwent emergency coronary angiography that showed a 95% distal left anterior descending coronary artery stenosis.