Fast assessment of left ventricular systolic function in obstructive sleep apnea patients with automated function imaging: Comparison with mitral annular plane systolic excursion.

BACKGROUND: Early detection of left ventricular (LV) subclinical dysfunction is clinically relevant before developing irreversible impairment in obstructive sleep apnea (OSA) patients. Mitral annulus plane systolic excursion (MAPSE) is a fast tool for OSA due to high prevalent obesity; another quick but more comprehensive tool is LV global longitudinal stain (GLS) based on automated function imaging (AFI). We therefore aimed to compare the feasibility and reproducibility of AFI to MAPSE in OSA patients, as a good model in whom obesity is common. METHODS: A comprehensive echocardiographic examination was done in 186 consecutive patients having polysomnography for suspected OSA. MAPSE was measured by using M-mode to calculate excursion of mitral annulus. GLS was derived by offline analysis of three long-axis views that semi-automatically detects LV endocardial boundary, which is adjusted manually as necessary with AFI measurement. Variability of AFI and MAPSE were compared among the different subgroups. RESULTS: Despite a relatively high obesity rate (42.9%), the feasibility of AFI was 94% (175/186) and that of 100% in MAPSE. AFI showed excellent correlation (r = .882) superior to MAPSE (r = .819) between the Expert and Beginner. Intra- and inter- observer variability of AFI and MAPSE in Bland-Altman analysis were 5.5% and 6.5%; 6.2% and 8.8%, respectively. In repeated measurements, AFI showed higher intra-class correlation (ICC = .95) than MAPSE (ICC = .87) (p < 0.05). Furthermore, analysis showed that AFI was feasible even in more obese patients (BMI≥28 kg/m2 ). CONCLUSIONS: Even in obese patients with OSA, AFI-GLS is feasible and more reliable for less expert operators than MAPSE in detecting LV longitudinal dysfunction.

Prognostic value of acoustic cardiography in patients with chronic heart failure.

BACKGROUND: Rapid risk stratification in patients with heart failure is critically important but challenging. The aim of our study is to ascertain whether acoustic cardiography can identify heart failure (HF) patients at high risk for mortality. METHODS: A total of 474 HF patients were enrolled into our study (76±11years old). Acoustic cardiographic parameters included S3 score (ie, third heart sound exists) and systolic dysfunction index (SDI) (correlated closely with left ventricular systolic dysfunction). The event-free survival curves were plotted by Kaplan-Meier method. Cox regression analysis was used to identify independent predictors for all-cause mortality. RESULTS: During a mean follow-up of 484days, 169 (35.7%) patients died and 126 (26.6%) were due to cardiac causes. After controlling for age, systolic blood pressure, hemoglobin, blood urea nitrogen, albumin, as well as ACEI and beta-blocker treatment in multivariate Cox regression analysis, SDI ≥5 and S3 score ≥4 were both independent predictors for all-cause mortality. Kaplan-Meier analysis showed that HF patients with SDI ≥5 or S3 score ≥4 had a significantly lower survival (52.2% vs. 69.2%, Log-rank χ(2)=18.07, P<0.001; 56.8% vs. 68.6%, Log-rank χ(2)=10.58, P=0.001, respectively) than those with lower SDI or S3 score. CONCLUSIONS: Acoustic cardiography could serve as a cost-effective and time-efficient tool to identify HF patients at high risk for mortality who might benefit from aggressive monitoring and intervention. It may improve assessment and initial disposition decisions in HF management.

Echocardiography, dyssynchrony, and the response to cardiac resynchronization therapy.

Biventricular pacing or cardiac resynchronization therapy (CRT) has been a considerable advance in the therapy of chronic heart failure. However, it is clear that not all patients benefit either in terms of symptoms or cardiac function, and some may be worsened by CRT. In this review, we consider the arguments, both clinical and economical, in favour of improved selection of patients for CRT other than those in current guidelines. It also seems clear that the fundamental mechanism of CRT is correction of dyssynchrony, and we review the various methodologies available to detect dyssynchrony. Other factors are probably also important in determining outcomes such as lead position, the extent and form of myocardial damage, optimizing pacemaker performance, and clinical expertise. The potential costs of inappropriate CRT implantation are high to our patients and to the health economy, and it behooves the cardiology community to develop better selection criteria. The current guidelines can and should be improved.

Energy intake and expenditure profile in chronic peritoneal dialysis patients complicated with circulatory congestion.

BACKGROUND: Circulatory congestion is an adverse predictor of mortality in peritoneal dialysis (PD) patients. OBJECTIVE: This study evaluated the nutritional status, energy intake, and expenditure profile of PD patients with and without previous circulatory congestion. DESIGN: We conducted a cross-sectional study in 244 PD patients, of whom 92 had previous circulatory congestion. We estimated dietary energy intake by using a locally validated 7-d food-frequency questionnaire and by assessing resting energy expenditure (REE) and total energy expenditure (TEE) with indirect calorimetry and a locally validated physical activity questionnaire, respectively. RESULTS: In comparison with those without circulatory congestion, patients with previous circulatory congestion were more malnourished by subjective global assessment (59% compared with 36%; P < 0.001), had lower handgrip strength, had lower midarm muscle circumference, had lower dietary protein (0.98 +/- 0.45 compared with 1.19 +/- 0.44 g x kg(-1) x d(-1); P < 0.001), and had lower energy intake (92.5 +/- 37.0 compared with 110.9 +/- 35.7 kJ x kg(-1) x d(-1); P < 0.001) but had higher C-reactive protein (P = 0.025) and higher REE (P < 0.001). However, no difference in TEE was noted between the 2 groups, which indicated lower activity energy expenditure among patients with previous circulatory congestion. The resulting energy balance was significantly more negative for patients with previous circulatory congestion than for those without previous circulatory congestion (P = 0.050). Furthermore, the prevalence of malnutrition increased with increasing episodes of circulatory congestion (P = 0.017). CONCLUSIONS: Patients with previous circulatory congestion had significantly more inflammation, more muscle wasting, and higher REE but lower activity energy expenditure and energy and protein intakes in keeping with an anorexia-cachexia syndrome. The mechanisms of increased REE and reduced energy intake among patients with previous circulatory congestion warrant further investigation.

The cardiac MRI substudy to ongoing telmisartan alone and in combination with ramipril global endpoint trial/telmisartan randomized assessment study in ACE-intolerant subjects with cardiovascular disease: analysis protocol and baseline characteristics.

BACKGROUND: The ONTARGET and TRANSCEND clinical trials were designed to investigate the cardioprotective effects of telmisartan 80 mg and ramipril 10 mg, alone and in combination, in patients at high risk of cardiovascular disease. Cardiac MRI enables investigation of mechanistic effects of these agents on cardiac structural and functional variables. Here, we report the design, analysis protocol, reproducibility and relevant quality control procedures, and baseline patient characteristics of the ONTARGET/TRANSCEND cardiac MRI substudy. MRI was undertaken in 330 subjects enrolled in ONTARGET, and 38 subjects in TRANSCEND, across eight centers in six countries. Analyses were performed by two independent analysts using guide-point modeling. Cases with discrepancies in LV mass (LVM) of >5% were independently reanalyzed. Cases with discrepancies in end-diastolic volume (EDV) of >5%, or end-systolic volume (ESV) of >12%, were then reconciled by consensus. RESULTS: Baseline characteristics were broadly similar to the main ONTARGET/TRANSCEND trials, except for a higher frequency of coronary artery disease and Asian ethnicity in the substudy. Reproducibility of MRI analyses (mean +/- SD) were 2.8 +/- 3.7 ml in EDV, -0.3 +/- 3.6 ml in ESV, 3.1 +/- 3.3 ml in SV, 1.1 +/- 1.8% in EF, and 0.4 +/- 4.5 g in LVM. Subgroup analyses revealed increased ESV and LVM, and reduced EF, in subjects with a history of either coronary artery disease or myocardial infarction. CONCLUSIONS: The ONTARGET/TRANSCEND cardiac MRI substudy protocol provides for a reliable assessment of the effects of telmisartan and ramipril, alone and in combination, on cardiac structural and functional parameters over a 2-year follow-up period.

Assessment of the effect of cardiac resynchronization therapy on intraventricular mechanical synchronicity by regional volumetric changes.

A new echocardiographic technology, the timing of regional volumetric changes by 3-dimensional echocardiography, was applied to assess intraventricular mechanical synchronicity in 13 patients who had received cardiac resynchronization therapy (CRT). When biventricular pacing was withheld, left ventricular (LV) asynchrony occurred as reflected by these echocardiographic parameters, whereas LV volume increased and the ejection fraction decreased. Further studies are needed to explore whether this novel method can be used to select suitable candidates for CRT and to predict a favorable response.

Resting energy expenditure and subsequent mortality risk in peritoneal dialysis patients.

Cardiovascular disease is the leading cause of death in ESRD patients and is strongly associated with malnutrition. The mechanism of malnutrition is not clear, but hypermetabolism is suggested to contribute to cardiac cachexia. This study examined resting energy expenditure (REE) in relation to the clinical outcomes of ESRD patients who receive continuous ambulatory peritoneal dialysis (CAPD) treatment. A prospective observational cohort study was performed in 251 CAPD patients. REE was measured at study baseline using indirect calorimetry together with other clinical, nutritional, and dialysis parameters. Patients were followed up for a mean +/- SD duration of 28.7 +/- 14.3 mo. REE was 39.1 +/- 9.6 and 40.1 +/- 9.0 kcal/kg fat-free edema-free body mass per day for men and women, respectively (P = 0.391). Using multiple regression analysis, fat-free edema-free body mass-adjusted REE was negatively associated with residual GFR (P < 0.001) and serum albumin (P = 0.046) and positively associated with diabetes (P = 0.002), cardiovascular disease (P = 0.009), and C-reactive protein (P = 0.009). At 2 yr, the overall survival was 63.3, 73.6, and 95.9% (P < 0.0001), and cardiovascular event-free survival was 72.3, 84.6, and 97.2% (P = 0.0003), respectively, for patients in the upper, middle, and lower tertiles of REE. Adjusting for age, gender, diabetes, and cardiovascular disease, patients in the upper and middle tertiles showed a 4.19-fold (95% confidence interval, 2.15 to 8.16; P < 0.001) and a 2.90-fold (95% confidence interval, 1.49, 5.63; P = 0.002) respective increase in the risk of all-cause mortality compared with those in the lower tertile. However, the significance of REE in predicting mortality was gradually reduced when additional adjustment was made for C-reactive protein, serum albumin, and residual GFR in a stepwise manner. In conclusion, a higher REE is associated with increased mortality and cardiovascular death in CAPD patients and is partly related to its close correlations with residual kidney function, cardiovascular disease, inflammation, and malnutrition in these patients.