Changes in skeletal muscle and organ size after a weight-loss intervention in overweight and obese type 2 diabetic patients.

BACKGROUND: The effect of a weight-loss intervention on the masses of lean tissues and organs in humans is not well known. OBJECTIVE: We studied the effects of a diet and exercise weight-loss intervention on skeletal muscle (SM) mass and selected organs over 2 y using MRI in overweight adults with type 2 diabetes. DESIGN: Participants were 53 women and 39 men [mean ± SD: age 58 ± 7 y; body mass index (BMI; in kg/m2) 32 ± 3] enrolled in the Look AHEAD (Action for Health in Diabetes) trial and randomly assigned to an intensive lifestyle intervention (ILI) or diabetes support and education (DSE) on whom 2 y of data were collected. MRI-derived measurements of SM, heart, liver, kidney, spleen, and pancreas were acquired. RESULTS: Adjusted for baseline weight, height, age, sex, and ethnicity, the ILI group weighed (mean ± SE) 6.6 ± 0.7 kg less after 1 y and 5.2 ± 0.7 kg less after 2 y, whereas the DSE group did not change significantly (-0.4 ± 0.6 and -1.0 ± 0.7 kg after 1 and 2 y, respectively; P-interaction < 0.001). Total SM decreased in both groups during year 1 (-1.4 ± 0.2 kg; P < 0.001) with appendicular SM regained during year 2. Liver and spleen masses decreased in the ILI group (-0.12 ± 0.02 and -0.006 ± 0.003 kg, respectively) but were unchanged in the DSE group (0.00 ± 0.02 and 0.004 ± 0.003 kg, respectively). Kidney mass decreased by 0.013 ± 0.003 kg (P < 0.001) over 2 y in both groups. CONCLUSIONS: Decreases in liver (in Caucasians but not African Americans) and spleen were detected after a 6.2-kg weight reduction compared with a control group. SM and kidney mass decreased in both groups. Appendicular SM was regained during the second year whereas trunk SM was not. No evidence of a disproportionate loss of high-metabolic rate organs (heart, liver, kidney, spleen) compared with SM was found.

Left Ventricular Metastasis from a Primary Pancreatobiliary Tumor.

Metastatic disease to the heart is not uncommon. We describe a case of a man in his 60s with an unusual metastasis to the heart and detail its intracardiac location by means of cardiac computerized tomography (CCT) and transthoracic echocardiography. To our knowledge, this is the first report of a pancreatobiliary tumor metastasizing exclusively to the left ventricle (LV) of the heart.

Changes in adipose tissue depots and metabolic markers following a 1-year diet and exercise intervention in overweight and obese patients with type 2 diabetes.

OBJECTIVE: We aim to characterize the effects on total body fat and distribution of a 1-year intensive lifestyle intervention (ILI) for weight loss in overweight and obese adults with type 2 diabetes and to examine whether changes in adipose tissue (AT) depots were associated with changes in metabolic biomarkers. RESEARCH DESIGN AND METHODS: Participants were 54 females and 38 males (age 57.8 ± 6.7 years [mean ± SD]; BMI 31.7 ± 3.5 kg/m(2)) enrolled in the Look AHEAD (Action for Health in Diabetes) trial randomized to ILI or diabetes support and education (DSE) from whom baseline and 1-year MRI measures of total AT (TAT) and regional (arm, trunk, leg) AT, including subcutaneous AT (SAT), visceral AT (VAT), and intermuscular AT (IMAT), were acquired. We tested whether mean changes in ILI and DSE were equal and, within groups, whether changes were different from zero. Regression models tested whether changes in AT compartments were associated with metabolic variable changes. RESULTS: Body weight changed -0.52 ± 3.62 kg (P = 0.31) in DSE and -7.24 ± 5.40 kg (P < 0.0001) in ILI. Mean ILI changes were different from DSE (P < 0.001 for TAT, SAT, and IMAT and P < 0.01 for VAT in females). Within ILI, SAT and VAT decreased in males and females (P < 0.0001), but IMAT was unchanged (0.00 ± 0.54 kg; P = 0.99). In DSE, SAT and VAT did not change, but IMAT increased by 0.46 ± 0.55 kg (P < 0.001). Controlling for weight loss, reduction of specific AT depots was associated with improvement in metabolic biomarkers. CONCLUSIONS: Weight loss of 7-10% from an ILI over 1 year reduced SAT and VAT and prevented an increase in IMAT. Reductions in AT depots were associated with improvements in biomarkers.

Skeletal muscle and organ masses differ in overweight adults with type 2 diabetes.

Whether lean body mass (LBM) composition, especially skeletal muscle and abdominal organs, differs in adults with type 2 diabetes (T2DM) compared with nondiabetic healthy controls has not been investigated. A subset of African-American and Caucasian participants with T2DM from the Look AHEAD (Action for Health in Diabetes) trial had body composition assessed and compared with a sample of healthy controls. Skeletal muscle mass (SMM), liver, kidneys, and spleen mass were quantified using a contiguous slice magnetic resonance imaging (MRI) protocol. Cardiac mass was quantified by either a cardiac gated MRI protocol or by echocardiography. MRI volumes were converted to mass using assumed densities. Dual-energy X-ray absorptiometry assessed LBM. Using general linear models adjusted for height, weight, sex, age, race, and interactions of diabetes status with race or sex, persons with T2DM (n = 95) had less LBM (49.7 vs. 51.6 kg) and SMM (24.1 vs. 25.4 kg) and larger kidneys (0.40 vs. 0.36 kg) than controls (n = 76) (all P < 0.01). Caucasians with T2DM had larger livers (1.90 vs. 1.60 kg, P < 0.0001) and spleens (0.29 vs. 0.22 kg, P < 0.01), and T2DM men had less cardiac mass than controls (0.25 vs. 0.30 kg, P < 0.001). In this sample, T2DM is characterized by less relative skeletal muscle and cardiac mass in conjunction with larger kidneys, liver, and spleen. Further investigation is needed to establish the causes and metabolic consequences of these race- and sex-specific organ mass differences in T2DM.

Multi-Detector Coronary CT Imaging for the Identification of Coronary Artery Stenoses in a "Real-World" Population.

BACKGROUND: Multi-detector computed tomography (CT) has emerged as a modality for the non-invasive assessment of coronary artery disease (CAD). Prior studies have selected patients for evaluation and have excluded many of the "real-world" patients commonly encountered in daily practice. We compared 64-detector-CT (64-CT) to conventional coronary angiography (CA) to investigate the accuracy of 64-CT in determining significant coronary stenoses in a "real-world" clinical population. METHODS: A total of 1,818 consecutive patients referred for 64-CT were evaluated. CT angiography was performed using the GE LightSpeed VCT (GE(®) Healthcare). Forty-one patients in whom 64-CT results prompted CA investigation were further evaluated, and results of the two diagnostic modalities were compared. RESULTS: A total of 164 coronary arteries and 410 coronary segments were evaluated in 41 patients (30 men, 11 women, age 39-85 years) who were identified by 64-CT to have significant coronary stenoses and who thereafter underwent CA. The overall per-vessel sensitivity, specificity, positive predictive value, negative predictive value, and accuracy at the 50% stenosis level were 86%, 84%, 65%, 95%, and 85%, respectively, and 77%, 93%, 61%, 97%, and 91%, respectively, in the per-segment analysis at the 50% stenosis level. CONCLUSION: 64-CT is an accurate imaging tool that allows a non-invasive assessment of significant CAD with a high diagnostic accuracy in a "real-world" population of patients. The sensitivity and specificity that we noted are not as high as those in prior reports, but we evaluated a population of patients that is typically encountered in clinical practice and therefore see more "real-world" results.

Novel computed tomography indexes of left atrial appendage stasis.

Contrast enhanced multi-detector computed tomography (MDCT) may detect left atrial appendage (LAA) thrombus; however, its ability to qualify LAA stasis has not been studied. We sought to identify MDCT derived LAA radiographic parameters which could qualify LAA stasis as defined by established transesophageal echocardiography (TEE) parameters. Pre-procedural MDCT followed by TEE (median procedural time difference of 11 days) from 45 patients who underwent ablation for atrial fibrillation were analyzed retrospectively. Contrast enhanced, non-gated, helical MDCT (64 detector row) was performed according to the institutional protocol. Using a combination of parametric and nonparametric tests, the mean attenuation and heterogeneity parameters of LAA attenuation were correlated with the presence of spontaneous echocardiographic contrast and Doppler derived LAA emptying velocity on TEE. If significant correlation is observed, a receiver operating curve analysis will be performed. The baseline characteristics of the studied population were; age, 62 ± 11; CHADS2 score, 2.0 ± 1.2; heart rate, 79 ± 10 bpm; left ventricular ejection fraction, 49 ± 14%. SEC was seen on TEE in 19 patients; ten with mild, eight with moderate, and one had severe SEC. No patients had LAA thrombus. Compared with the group without SEC, those with SEC had significantly increased coefficient of variation (0.19 vs. 0.14, p = 0.014) and range to mean ratio (1.04 vs. 0.73, p = 0.011). There was no significant correlation between mean LAA attenuation and LAA emptying velocity. However, the range, range to mean ratio, standard deviation and coefficient of variation of LAA attenuation had a significantly negative correlation with LAA emptying velocity (r = -0.486, r = -0.497, r = -0.434, r = -0.466, respectively, all p < 0.05). On receiver operating curve analysis, each of the heterogeneity parameters significantly discriminated LAA emptying velocities ≤30 cm/s, with areas under the curve of 0.88, 0.83, 0.81 and 0.76 respectively. In patients with atrial fibrillation, increased contrast heterogeneity within the LAA on MDCT correlated with decreased LAA emptying velocity on TEE. Contrast enhanced MDCT provides an adjunctive, noninvasive technique for Qualification of LAA stasis.

Not all obstructive cardiac lesions are created equal: double-chamber right ventricle in pregnancy.

Double-chambered right ventricle (DCRV) is a rare form of right ventricular outflow tract (RVOT) obstruction accounting for approximately 1% of patients with congenital heart disease. It consists of an anomalous muscle bundle that divides the right ventricle usually between the sinus (inlet) and the infundibulum (outlet). This division creates a proximal chamber with high pressure and a distal chamber with low pressure. The hemodynamic obstruction of the RVOT is usually an acquired phenomenon, however the substrate for the anomalous muscle bundle is likely congenital. The diagnosis of DCRV should be considered in the young patient with an elevated right ventricular systolic pressure and intracavitary gradient. Echocardiography and cardiac MRI are the principal diagnostic tools for the assessment of DCRV. This entity is often misdiagnosed as pulmonary hypertension in the young patient, and can often go overlooked and untreated for many years. Definitive therapy involves surgical resection of the muscle bundle. This can often be curative and if done in a timely fashion, may prevent right ventricular remodeling. We describe the unique diagnostic dilemma, the course and management of a young adult with DCRV during pregnancy.

Brain and high metabolic rate organ mass: contributions to resting energy expenditure beyond fat-free mass.

BACKGROUND: The degree to which interindividual variation in the mass of select high metabolic rate organs (HMROs) mediates variability in resting energy expenditure (REE) is unknown. OBJECTIVE: The objective was to investigate how much REE variability is explained by differences in HMRO mass in adults and whether age, sex, and race independently predict REE after adjustment for HMRO. DESIGN: A cross-sectional evaluation of 55 women [30 African Americans aged 48.7 +/- 22.2 y (mean +/- SD) and 25 whites aged 46.4 +/- 17.7 y] and 32 men (8 African Americans aged 34.3 +/- 18.2 y and 24 whites aged 51.3 +/- 20.6 y) was conducted. Liver, kidney, spleen, heart, and brain masses were measured by magnetic resonance imaging, and fat and fat-free mass (FFM) were measured by dual-energy X-ray absorptiometry. REE was measured by indirect calorimetry. RESULTS: REE estimated from age (P = 0.001), race (P = 0.006), sex (P = 0.31), fat (P = 0.001), and FFM (P < 0.001) accounted for 70% (adjusted (2)) of the variability in REE. The addition of trunk HMRO (P = 0.001) and brain (P = 0.006) to the model increased the explained variance to 75% and rendered the contributions of age, sex, and race statistically nonsignificant, whereas fat and FFM continued to make significant contributions (both P < 0.05). The addition of brain to the model rendered the intercept (69 kcal . kg(-1) . d(-1)) consistent with zero, which indicated zero REE for zero body mass. CONCLUSIONS: Relatively small interindividual variation in HMRO mass significantly affects REE and reduces the role of age, race, and sex in explaining REE. Decreases in REE with increasing age may be partly related to age-associated changes in the relative size of FFM components.

Can computed tomography improve outcomes in acute coronary syndrome?

Each year, six million patients in the USA visit the emergency department for acute chest pain. Many patients are hospitalized because immediate discharge of those suspected of acute coronary syndrome could be disastrous. This review looks at whether patient outcomes could be improved by coronary computed tomography angiography.

Isolated subacute effusive and nonconstrictive epicarditis masquerading as a right atrial mass.

Epicarditis (visceral pericardial inflammation) is a very unique and rare diagnosis. It is almost always associated with parietal pericardial involvement and may occur in medical conditions such as viral, bacterial (mycobacterial) infections and uremia or postoperatively in the setting of cardiac surgery. Frequently, no etiology is found. Most cases are associated with constrictive physiology, and patients present with symptoms and signs of right-sided heart failure. Effusive epicarditis is often present, and the clinical features may easily be confused with those of pericardial effusion with tamponade. We report a unique case of isolated subacute effusive and nonconstrictive epicarditis mimicking a right atrial mass in a 72-year-old patient who was diagnosed with nonmetastatic gastric adenocarcinoma. Our case is unique for several reasons: inflammation was limited to the epicardium (very few cases have been described to date); the patient was asymptomatic, with no clinical or echocardiographic evidence of constriction (this represents a novel finding, explained in part by the more limited extent of inflammation, with no significant fibrotic component and no parietal pericardial involvement); and this is the first report of epicarditis occurring in association with a malignancy, which we hypothesize may represent an inflammatory paraneoplastic process.

Smaller organ mass with greater age, except for heart.

Autopsy/cadaver data indicate that many organs and tissues are smaller in the elderly compared with young adults; however, in vivo data are lacking. The aim of this study was to determine whether the mass of specific high-metabolic-rate organs is different with increasing age, using MRI. Seventy-five healthy women (41 African-Americans and 34 Caucasians, age range 19-88 yr) and 36 men (8 African-Americans and 28 Caucasians, age range 19-84 yr) were studied. MRI-derived in vivo measures of brain, heart, kidneys, liver, and spleen were acquired. Left ventricular mass (LVM) was measured by either echocardiography or cardiac gated MRI. Total body fat mass and fat-free mass (FFM) were measured with a whole body dual-energy X-ray absorptiometry (DXA) scanner. Multiple regression analysis was used to investigate the association between the organ mass and age after adjustment for weight and height (or DXA measures of FFM), race, sex, and interactions among these variable. No statistically significant interaction was found among age, sex, and race in any regression model. Significant negative relationships between organ mass and age were found for brain (P < 0.0001), kidneys (P = 0.01), liver (P = 0.001), and spleen (P < 0.0001). A positive relationship between LVM and age was found after adjustment for FFM (P = 0.037). These findings demonstrate that age has a significant effect on brain, kidneys, liver, spleen, and heart mass. The age effect was independent of race and sex.

Adipose tissue distribution is different in type 2 diabetes.

BACKGROUND: The extent to which adipose tissue (AT) distribution is different between persons with type 2 diabetes (T2DM) and nondiabetic control subjects remains unclear. OBJECTIVE: The aim of this study was to establish whether total body adiposity and its distribution, quantified by using state-of-the-art whole-body magnetic resonance imaging, differs between these 2 groups. DESIGN: This cross-sectional evaluation included 93 participants (n = 56 women and 37 men) in the Look AHEAD (Action for HEAlth in Diabetes) Trial with T2DM who had a mean (+/-SD) age of 58.3 +/- 6.6 y and body mass index (in kg/m(2)) of 31.6 +/- 3.1 and 93 healthy non-T2DM control subjects (n = 64 women and 29 men) who had a mean (+/-SD) age of 60.6 +/- 17.1 y and body mass index of 29.6 +/- 3.0. All participants self-reported being of African American or white ancestry. Magnetic resonance imaging-derived in vivo measures of total-body AT (TAT) and its distribution, subcutaneous AT (SAT), visceral AT (VAT), and intermuscular AT (IMAT) were acquired. Linear regression models were developed for each AT compartment to adjust for important covariates of race, sex, age, height, and weight and to examine potential interactions of covariates. RESULTS: These models showed significantly less SAT (African American: -1.2 kg; white: -2.4 kg; both P = 0.001), including less femoral-gluteal SAT, more VAT (African American: 0.7 kg, P < 0.001; white: 1.8 kg, P = 0.007), and more IMAT (0.5 kg, P = 0.001) in the T2DM group. CONCLUSION: We concluded that AT distribution is significantly altered in T2DM, ie, more VAT and IMAT--2 depots known to exacerbate insulin resistance--and less SAT in persons with T2DM than in healthy control subjects, a novel finding that we posit may compound the risk of insulin resistance.

Demonstration of left ventricular outflow tract eccentricity by 64-slice multi-detector CT.

BACKGROUND: Newer three-dimensional imaging technologies provide insight into cardiac shape and geometry from views previously unobtainable. Standard formulae like the continuity equation (CE) that rely on inherent assumptions about left ventricular outflow tract (LVOT) shape may need to be revisited. In the CE, small changes in LVOT diameter may significantly change calculated aortic valve area (AVA). Using 64-slice Multi-detector CT (MDCT), we performed LVOT planimetry to obviate the need for any geometric assumptions. METHODS: 64-slice MDCT was performed in 30 consecutive patients. The diameter-derived LVOT area (ALVOTdiam) was calculated from a view analogous to the 2D echo parasternal long axis. Direct planimetry of the LVOT (ALVOTplan) was performed just beneath the aortic valve in a plane perpendicular to the LVOT long axis. Further, assuming an ellipsoid outflow tract shape, LVOT area (ALVOTellip) was calculated using piab from the long and short diameters of the planimetered LVOT view. Eccentricity index (EI) was estimated by subtracting the ratio of shortest and longest LVOT diameters from one. RESULTS: ALVOTdiam always measured smaller than ALVOTplan (mean 3.7 +/- 1.2 cm2 vs. 4.1 +/- 1.3 cm2, respectively). The median EI was 0.18 (95% CI = 0.16-0.2; P = 0.0001). ALVOTellip more closely agreed with ALVOTplan (correlation = 0.96; P < 0.0001) than did ALVOTdiam (correlation = 0.87; P < 0.0001). CONCLUSION: Using MDCT, the LVOT was shown to be elliptical in most patients. Applying the CE which assumes roundness of the LVOT consistently underestimated the LVOT area which may affect estimated AVA. Planimetry of the LVOT utilizing three-dimensional imaging modalities such as 3-D echocardiography, MRI, or MDCT may render a more precise AVA.