Changes In Cardiac Geometry Research Articles

Ambulatory Blood Pressure Phenotypes in Children and Adolescents

Ambulatory Blood Pressure Phenotypes in Children and Adolescents

P932Structural changes in left ventricle after transcatheter aortic valve implantation

Abstract Background Transcatheter aortic valve implantation (TAVI) has improved prognosis and quality of life of patients with severe aortic stenosis (AS) who had been considered inoperable or at high risk for surgical aortic valve replacement reflecting their age, frailty, and comorbidities. However, less is known about changes in cardiac geometry after TAVI procedure, and predictors of them. Purpose To clarify changes in cardiac geometry after TAVI, and their predictors. Methods We retrospectively analyzed patients with severe AS who underwent TAVI in our institute between May 2016 and June 2018. Of the 117 consecutive patients enrolled to this study, 12 patients died before six-month follow up, and finally 88 patients received follow up exams including echocardiography at six months after TAVI procedure. Results The analysis of echocardiographic data at the baseline and the six-month follow up of the 88 patients (age 86.2±4.0 years, male 19.3%, STS-PROM 6.76±3.28%, peak aortic jet velocity 4.67±0.75m/s) revealed that left ventricular end-diastolic volume index (LVEDVi) (from 80.1±20.9ml/m2to 74.2±15.9ml/m2, p=0.011), and left ventricular mass index (LVMi) (from 116.0±32.7g/m2to 93.6±25.6g/m2, p<0.001) had improved in six months after TAVI procedure. The difference of LVEDVi (ΔLVEDVi: six-month LVEDVi–baseline LVEDVi) and the difference of LVMi (ΔLVMi: six-month LVMi – baseline LVMi) were significantly higher in the patients with chronic atrial fibrillation compared to the rest (ΔLVEDVi: +7.7±8.7ml/m2 vs −7.2±18.1ml/m2, p=0.024; ΔLVMi: +7.1±11.5g/m2 vs −25.3±33.5g/m2, p=0.008). In echocardiographic data, ΔLVEDVi and ΔLVMi both had positive correlation between baseline E/e' ratio (ΔLVEDVi: r=0.224, p=0.048; ΔLVMi: r=0.240, p=0.034), and negative correlation between baseline LVEDVi (ΔLVEDVi: r=−0.674, p<0.001; ΔLVMi: r=−0.312, p=0.003), LVMi (ΔLVEDVi: r=−0.422, p<0.001; ΔLVMi: r=−0.699, p<0.001), peak aortic jet velocity (ΔLVEDVi: r=−0.257, p=0.016; ΔLVMi: r=−0.376, p<0.001), and mean transaortic pressure gradient (ΔLVEDVi: r=−0.269, p=0.011; ΔLVMi: r=−0.403, p<0.001). Conclusion TAVI resulted in reverse remodeling and regression of hypertrophy in left ventricle. And these improvement were grater in patients with more advanced left ventricular remodeling and hypertrophy, and higher severity of AS at the baseline, however, less in patients with chronic atrial fibrillation and worse diastolic dysfunction.

University athletes and changes in cardiac geometry: insight from the 2015 Gwangju Summer Universiade.

There is a paucity of data regarding the changes of cardiac geometry in highly trained international and multiracial university athletes. We aimed to investigate the incidence of structural cardiac abnormalities and changes of cardiac geometry in highly trained university athletes. Comprehensive echocardiographic studies were performed in 1185 university athletes through the Check-up Your Heart Program during the 2015 Gwangju Summer Universiade. Participants were divided into two groups: normal vs. abnormal left ventricular (LV) geometry (concentric remodelling, concentric hypertrophy, or eccentric hypertrophy). Structural heart diseases associated with sudden cardiac death were not identified, but minor structural cardiac abnormalities were common in university athletes. One hundred and fifty-six athletes (13.2%) had abnormal LV geometry; concentric remodelling (n = 73, 6.2%), concentric hypertrophy (n = 25, 2.1%), and eccentric hypertrophy (n = 58, 4.9%). Abnormal LV geometry was significantly more common in athletes of African descent and in endurance, mixed, or power disciplines. In multivariate logistic regression analysis, athletes of African descent [odds ratio (OR) 2.16, 95% confidence interval (CI) 1.34-3.46; P = 0.001], endurance disciplines (OR 1.79, 95% CI 1.26-2.54; P = 0.001), and training time (OR 1.01, 95% CI 1.00-1.02; P = 0.045) were independent predictors of abnormal LV geometry. A large scale cardiovascular screening programme of the 2015 Summer Universiade demonstrated that abnormal LV geometry is not uncommon (13.2%) and concentric remodelling is the most common pattern of LV geometric change in young trained university athletes. Race, type of sport, and training time are significant predictors of abnormal LV geometry. Structural cardiac abnormalities are common in university athletes even though they are minor abnormalities.

Cardiomyocyte-specific knockout of endothelin receptor a attenuates obesity cardiomyopathy

Endothelin (ET)-1 is implicated in the pathophysiology of cardiovascular diseases although its role in obesity anomalies has not been fully elucidated. This study was designed to examine the impact of ET-1 receptor A (ETA) ablation on obesity-induced changes in cardiac geometry and contractile function, as well as the mechanisms involved with a focus on autophagy. Cardiomyocyte-specific ETA receptor knockout (ETAKO) and WT mice were fed either low-fat (10% calorie from fat) or high-fat (45% calorie from fat) diet for 24 weeks. Glucose tolerance test was examined to confirm insulin resistance. High-fat diet intake compromised myocardial geometry (enlarged left ventricular diameters in systole and diastole), morphology (cardiac hypertrophy, increased wall thickness and interstitial fibrosis), contractile function (reduced fractional shortening, ejection fraction and cardiomyocyte shortening) and intracellular Ca2+ handling, the effect of which was significantly attenuated by ETAKO. TUNEL staining revealed overt apoptosis in high-fat-fed group, the effect was reverted by ETAKO. Western blot analysis noted that high-fat intake downregulated leptin receptor and PPARγ, insulin signaling (elevated basal/dampened insulin-stimulated phosphorylation of Akt and IRS1), phosphorylation of AMPK, ACC, upregulated GATA-4, ANP, NFATc3, PPARα, m-TOR/p70s6k signaling, which were attenuated by ETAKO with the exception of AMPK/ACC. Furthermore, high-fat intake suppressed cardiac autophagy, which was abrogated by ETAKO. In cultured murine cardiomyocytes, palmitic acid challenged mimicked high-fat diet-induced hypertrophic and autophagic responses, the effect of which were abolished by the ETA receptor antagonist BQ123 or mTOR inhibitor rapamycin. These results suggest that inhibition of ETA rescues high-fat intake-induced cardiac anomalies possibly through autophagy regulation.

P 3 Relationship between maternal cardiac remodeling in preeclampsia and pregnancy outcome

Introduction It was well known that changes in cardiac geometry during pregnancy were more pronounced in pregnancy complicated by preeclampsia (PE). We were interested whether pregnancy outcome was more affected by changes in cardiac remodeling. Objectives The purpose of this study was to determine the relationship of changes in geometry of the left ventricle (LV) with the intrauterine growth restriction (IUGR) and preterm delivery in PE women. Methods Sixty hypertensive women with PE and 30 normotensive pregnant women without PE as controls, in the third trimester underwent a complete echocardiography that was used to assess parameters of chamber quantification and wall thickness. Relative wall thickness (RWT) was calculated as RWT = 2 x PWd/LVEDd. LV myocardial mass in grams was calculated by the Devereux formula and then was normalized for BSA as LV mass index – LVmassi (g/m2). The LV remodeling was determined as normal geometry (NG), concentric hypertrophy (CH), eccentric hypertrophy (EH) and concentric remodeling (CR) according to the reference values of RWT and LVmass index due to recommendations of Europian Association of Cardiovascular Imaging and American Society of Echocardiography. Results There werent statistically significant differences between groups in the following parameters: age, heart rate, height, weight. PE women had statistically significant higher values in almost parameters of the LV geometry, that caused most abnormal geometry in women with PE. Most controls had NG, while CH was most presented in PE 31,7% vs 3.3% in controls (p Conclusion Pregnancy outcome in preeclampsia was statistically significant associated with changes in cardiac remodeling, particularly LVmass i .

Natural History of Myocardial Function in an Adult Human Population: Serial Longitudinal Observations From MESA

ObjectivesThe aim of this longitudinal study was to define the determinants of aging-related left ventricular (LV) remodeling and function in a large multiethnic population. BackgroundThe influence of risk factor exposure on myocardial remodeling and function in humans across adult life remains incompletely understood. MESA (Multi-Ethnic Study of Atherosclerosis) is a longitudinal population-based cohort of asymptomatic adults at baseline. MethodsWe examined 757 participants who were free of clinical cardiovascular disease and underwent tagged cardiac magnetic resonance both at baseline and at the 10-year follow-up as part of the MESA study. LV remodeling, circumferential shortening (CS), and torsion were assessed by tagged cardiac magnetic resonance. Multivariable linear regression was used to determine the association of changes in risk factors with changes in cardiac geometry and function. ResultsThe mean age of participants was 63 ± 9 years at baseline; 50% were women. Overall, the LV mass-to-volume ratio increased by 10% over 10 years (p < 0.01). CS was unchanged (17.8% to 17.9%, p = 0.246), whereas torsion increased by 13% (3.8°/cm to 4.3°/cm, p < 0.001). Increased systolic blood pressure was associated with reduced CS (−0.02%/mm Hg, p < 0.01). Participants who remained on antihypertensive therapy during the whole study had a greater decrease in LV mass-to-volume ratio (−0.045 vs. no medication, p < 0.05) with a greater increase in CS (0.78% vs. no medication, p < 0.01). Moreover, greater LV mass at baseline was significantly associated with reduced CS (−0.02%/g, p < 0.01) and torsion (−0.02°/cm/g, p < 0.01) independently of risk factors. ConclusionsLongitudinal observation demonstrates that LV mass and worsening risk factors are fundamental determinants of reduced regional myocardial shortening over 10 years. Increased torsion of the myocardial wall is seen with progressive concentric remodeling and may explain why systolic function is maintained with aging.

Cardiac remodeling and dysfunction in childhood obesity: a cardiovascular magnetic resonance study.

BackgroundObesity affects nearly one in five children and is associated with increased risk of premature death. Obesity-related heart disease contributes to premature death. We aimed to use cardiovascular magnetic resonance (CMR) to comprehensively characterize the changes in cardiac geometry and function in obese children.Methods and resultsForty-one obese/overweight (age 12 ± 3 years, 56 % female) and 29 healthy weight children (age 14 ± 3 years, 41 % female) underwent CMR, including both standard cine imaging and displacement encoded imaging, for a complete assessment of left ventricular (LV) structure and function. After adjusting for age, LV mass index was 23 % greater (27 ± 4 g/m2.7 vs 22 ± 3 g/m2.7, p <0.001) and the LV myocardium was 10 % thicker (5.6 ± 0.8 mm vs 5.1 ± 0.8 mm, p <0.001) in the obese/overweight children. This evidence of cardiac remodeling was present in obese children as young as age 8. Twenty four percent of obese/overweight children had concentric hypertrophy, 59 % had normal geometry and 17 % had either eccentric hypertrophy or concentric remodeling. LV mass index, thickness, ejection fraction and peak longitudinal and circumferential strains all correlated with epicardial adipose tissue after adjusting for height and gender (all p <0.05). Peak longitudinal and circumferential strains showed a significant relationship with the type of LV remodeling, and were most impaired in children with concentric hypertrophy (p <0.001 and p = 0.003, respectively).ConclusionsObese children show evidence of significant cardiac remodeling and dysfunction, which begins as young as age 8. Obese children with concentric hypertrophy and impaired strain may represent a particularly high risk subgroup that demands further investigation.Electronic supplementary materialThe online version of this article (doi:10.1186/s12968-016-0247-0) contains supplementary material, which is available to authorized users.

Flow reduction in high-flow arteriovenous fistulas improve cardiovascular parameters and decreases need for hospitalization.

High output heart failure (HF) and pulmonary hypertension have been demonstrated in patients with prevalent arteriovenous (AV) fistulas. Fistulas with flow >2000 mL/minutes are more likely to induce changes in cardiac geometry and pulmonary artery pressure. The effects of reducing flow in AV access and its implications on HF decompensation and hospitalizations have not been studied. Retrospective analysis of 12 patients who needed hospitalization for acute Congestive Heart Failure (CHF) decompensation with AV access flow of 2 L/minutes (as defined by Kidney Disease Outcomes Quality Initiative (KDOQI)) or more were included in the study. All the patients underwent banding of their inflow at the anastomosis with perioperative access flow measurement. Follow-up period was 6 months. 2D echo was done at 6 months postbanding in addition to access flow and clinical evaluation. Complete data was available for all the 12 patients. Study data was collected on all the 12 patients. Mean age was 64.7 years. The mean access flow pre and postbanding were 3784 mL/minutes and 1178 mL/minutes, respectively (P < 0.001). Eighty percent of the patients had diabetes and 41% had coronary artery disease. There was a statistically significant decrease in cardiac output (pre = 7.06 L/minutes, post = 6.47 L/minutes P = 0.03), pulmonary systolic pressure (pre = 54 mmHg, post = 44 mmHg P = 0.02), left ventricular mass index (LVMI) (pre = 130 g/m(2) , post = 125 g/m(2) P = 0.006) and need for rehospitalization for CHF decompensation. The New York Heart Association (NYHA) staging improved by 1 stage postbanding (P = 0.002). The hospitalization rate was 3.75 ± 1.2 in the 6 months before banding and was decreased to 1.08 ± 1.2 (P = 0.002) postbanding. The hemoglobin level, predialysis systolic blood pressure, calcium phosphorous product and the use of Renin Angiotensin Aldosterone System (RAAS) blockade agents and calcium channel blockers were comparable before and after inflow banding. Flow reduction in high flow fistulas are associated with decreased LVMI and pulmonary artery pressures. There is also a significant reduction in the risk for hospitalization due to acute HF and an improvement in NYHA heart failure stage.

Correlation of Left Ventricular Diastolic Function and Left Ventricular Geometry in Patients with Obstructive Sleep Apnoea Syndrome.

The aim of this study is to evaluate the correlation of the left ventricular diastolic function and the left ventricular geometry in patients with obstructive sleep apnoea syndrome (OSAS) by echocardiography. The 181 patients diagnosed with OSAS were divided into the normal geometry group (NG), the concentric remodelling group (CR), the eccentric hypertrophy group (EH) and the concentric hypertrophy group (CH). Pearson correlation analysis and multiple linear regression analysis were performed toward the correlation of the left ventricular diastolic function and the left ventricular geometry. The E peak in the EH and CH group was significantly reduced, with significant difference; the E/A, Em, Am and Em/Am was reduced in the order of the CR, EH and CH groups, while E/Em was increased, and the difference was significant. Pearson correlation analysis revealed that the Em/Am showed significant negative correlations with the left ventricular mass index (LVMI) [r = -0.419] and relative wall thickness (RWT) [r = -0.289], while the E/Em was significantly positively correlated with the LVMI (r = 0.638) and RWT [r = 0.328] (p < 0.001). Multiple linear regression analysis revealed that LVMI and RWT had influence on the Em/Am and E/Em (r2 = 0.402, r2 = 0.107, p < 0.001). The left ventricular diastolic dysfunction was the worst in the CH group. There was correlation between the left ventricular diastolic dysfunction and the changes in cardiac geometry.

Relationship of Body Mass Index with Changes in Cardiac Geometry and Function in 5,898 Patients Evaluated by Transthoracic Echocardiography

Introduction: This study describes the relationship between Body Mass Index (BMI) and the cardiac geometry and heart function assessed by transthoracic echocardiography. Materials and methods: We analyzed 5,898 echocardiographic studies in an age range between 18.0 and 98.6 years. Results: The BMI ranged from 15.23 to 49.61 kg/m2. The increased BMI had a statistically significant direct association with left ventricular mass initially observing a light concentric hypertrophy, which becomes eccentric as it increases, especially when allometric ratio is normalized (Height2.7). An increase in ejection volume and cardiac output was observed, as well as an inverse association between body mass index and the E/A ratio of mitral filling, with a significant reduction of e’ velocity of tissue Doppler, showing a relaxation-type diastolic dysfunction in overweight or obese individuals. We observed a slight yet significant increase in the left atrial area and volume indexed to body mass. There were no differences in the right ventricular geometry and function. Conclusions: The present study demonstrated a significant direct association between the increase in BMI and LV myocardial mass. Indexing LV mass to height 2.7 avoids artifacts related to body mass index, especially in subjects with grade II and III obesity. (Arq Bras Cardiol: Imagem cardiovasc. 2015; 28(1):3-16)

Abstract 178: Exercise Augments Cardiac Akt Activity And Reverses Aging-related Systolic Dysfunction.

Purpose: Aging is one of the primary factors causing left-ventricular (LV) remodeling and susceptibility to heart failure (HF). Clinical evidences demonstrate a sustained exercise (EX) ameliorates HF; however, the molecular mechanism underlying the aging-related LV remodeling remains uncertain and few data have demonstrated whether EX may be beneficial for the aging-related LV remodeling and contractility. Because preclinical studies indicate the pivotal role of protein kinase Akt in aging, we thus hypothesized whether EX may exert benefits on HF induced by aging in which Akt may play an essential role. Methods: Male aged (40 w/o) and young (14 w/o) C57BL6 mice were subjected to the EX (45-min running (10~20m/s, 5-degree) on treadmill every second day for 15 weeks; agedC57EX and agedC57CON). To elucidate the role of Akt in aging heart, age- and gender-matched Akt knockout mice were also enrolled. Results: Aging impairs both systolic and diastolic function without any changes in cardiac geometry. The systolic dysfunction of agedC57 reversed by EX with concomitant Akt activation; however, its diastolic dysfunction remained unaffected. EX enhanced cardiac Akt activity independently of aging. Aged AktKO exhibited systolic dysfunction to the more severe extent, which was reversed by EX. Conclusions: Our study demonstrates that #1 Akt is essential for adaptive cardiac contractility both to EX and aging. #2 Aging promotes diastolic dysfunction independently of Akt axis.

Antioxidant catalase rescues against high fat diet-induced cardiac dysfunction via an IKKβ-AMPK-dependent regulation of autophagy

Autophagy, a conservative degradation process for long-lived and damaged proteins, participates in a variety of biological processes including obesity. However, the precise mechanism of action behind obesity-induced changes in autophagy still remains elusive. This study was designed to examine the role of the antioxidant catalase in high fat diet-induced changes in cardiac geometry and function as well as the underlying mechanism of action involved with a focus on autophagy. Wild-type (WT) and transgenic mice with cardiac overexpression of catalase were fed low or high fat diet for 20weeks prior to assessment of myocardial geometry and function. High fat diet intake triggered obesity, hyperinsulinemia, and hypertriglyceridemia, the effects of which were unaffected by catalase transgene. Myocardial geometry and function were compromised with fat diet intake as manifested by cardiac hypertrophy, enlarged left ventricular end systolic and diastolic diameters, fractional shortening, cardiomyocyte contractile capacity and intracellular Ca2+ mishandling, the effects of which were ameliorated by catalase. High fat diet intake promoted reactive oxygen species production and suppressed autophagy in the heart, the effects of which were attenuated by catalase. High fat diet intake dampened phosphorylation of inhibitor kappa B kinase β(IKKβ), AMP-activated protein kinase (AMPK) and tuberous sclerosis 2 (TSC2) while promoting phosphorylation of mTOR, the effects of which were ablated by catalase. In vitro study revealed that palmitic acid compromised cardiomyocyte autophagy and contractile function in a manner reminiscent of fat diet intake, the effect of which was significantly alleviated by inhibition of IKKβ, activation of AMPK and induction of autophagy. Taken together, our data revealed that the antioxidant catalase counteracts against high fat diet-induced cardiac geometric and functional anomalies possibly via an IKKβ-AMPK-dependent restoration of myocardial autophagy. This article is part of a Special Issue entitled: Autophagy and protein quality control in cardiometabolic diseases.

English

BACKGROUND AND OBJECTIVES: In the last decade, anemia is recognized as an important cause of morbidity, a factor limiting physical activity, responsible for a poor quality of life, and a predictor of unfavorable outcomes. Anemia is emerging as a potential contributor to the development and progression of cardiovascular disease. Hence the present study was undertaken to correlate echocardiographic changes with anemic status. METHODOLOGY: Present study was conducted in Al-Ameen Medical College and Government district Hospital, Bijapur. 31 anemic patients (aged 18-40 yrs.) with Hb ≤7 gm. % were selected. All anemic patients were subjected for hemoglobin estimation and M mode 2D Echocardiography. Echocardiographic parametersIVSTd, LVIDd, LVPWd, IVSTs, LVIDs, LVPWS, EDV, ESV, SV, SI, CI, EF, FS were studied and correlated with hemoglobin levels. Statistical analysis was done by correlation analysis. RESULTS: LVPWd, IVSTs, IVStd, LVPWs did not correlate with hemoglobin levels. LVIDd, LVIDs, EDV, ESV, SV, SI, CI were negatively correlated with hemoglobin levels in anemic patients. No correlation observed for EF, FS. INTERPRETATION AND CONCLUSION: The findings of negative correlation of echo parameters with anemic status may be as a consequence of hyperdynamic circulatory state leading to vascular and cardiac changes. These changes are mainly due to increased preload, decreased afterload, changes in cardiac geometry. These factors increase systolic wall stress and over time lead to LV systolic dysfunction.

Association of serum adiponectin and insulin-like growth factor I levels with parameters of cardiac remodeling in severely obese patients.

Obesity is associated with various changes in cardiac geometry and this process involves both hemodynamic and non-hemodynamic factors, among which adipocitokines and growth factors may play an important role. The aim of this study was to identify the extent and pattern of cardiac remodeling in a group of severely obese patients and analyze the relationship between adiponectin, IGFI and cardiac parameters reflecting obesity-associated structural changes. Our study included 344 patients (104 men) with severe obesity [mean body mass index (BMI)= 45.7 ± 8.5 kg/m(2)], extensively evaluated clinically and biologically (complete metabolic tests, serum adiponectin, and IGF-I measurements). Left ventricular (LV) mass index (LVMI), left atrium (LA) size, and LV geometry were determined by means of cardiac ultrasound. The most prevalent pattern of LV geometry was eccentric hypertrophy (28.7% of patients). In a gender-, age-, BMI-, diabetes- and hypertension-adjusted general linear model, patients with concentric or eccentric hypertrophy had significantly lower values of adiponectin than those with normal geometry (6.75 ± 0.41, 6.96 ± 0.53, vs 9.04 ± 0.42 mg/l, p<0.05). In multivariate analysis, independent determinants for LVMI were BMI (β=0.364, p<0.001), systolic blood pressure (BP) (β=0.187, p=0.004), age (β=0.246, p<0.001), adiponectin (β=-0.151, p=0.012), and IGF-I z-score (β=0.134, p=0.025) while factors independently related to LA size were systolic BP (β=0.218, p<0.001), BMI (β=0.194, p<0.001), age (β=0.273, p<0.001), gender (β=-0.195, p<0.001), and adiponectin (β=-0.180, p=0.005). In patients with severe obesity, IGF-I z score and adiponectin correlate with parameters of cardiac remodeling independently of anthropometric, hemodynamic or metabolic factors.

Favorable Changes in Cardiac Geometry and Function Following Gastric Bypass Surgery: 2-Year Follow-Up in the Utah Obesity Study

The objective of this study was to test the hypothesis that gastric bypass surgery (GBS) would favorably impact cardiac remodeling and function. GBS is increasingly used to treat severe obesity, but there are limited outcome data. We prospectively studied 423 severely obese patients undergoing GBS and a reference group of severely obese subjects that did not have surgery (n = 733). At a 2-year follow up, GBS subjects had a large reduction in body mass index compared with the reference group (−15.4 ± 7.2 kg/m2 vs. −0.03 ± 4.0 kg/m2; p < 0.0001), as well as significant reductions in waist circumference, systolic blood pressure, heart rate, triglycerides, low-density lipoprotein cholesterol, and insulin resistance. High-density lipoprotein cholesterol increased. The GBS group had reductions in left ventricular (LV) mass index and right ventricular (RV) cavity area. Left atrial volume did not change in GBS but increased in reference subjects. In conjunction with reduced chamber sizes, GBS subjects also had increased LV midwall fractional shortening and RV fractional area change. In multivariable analysis, age, change in body mass index, severity of nocturnal hypoxemia, E/E′, and sex were independently associated with LV mass index, whereas surgical status, change in waist circumference, and change in insulin resistance were not. Marked weight loss in patients undergoing GBS was associated with reverse cardiac remodeling and improved LV and RV function. These data support the use of bariatric surgery to prevent cardiovascular complications in severe obesity.

The impact of short daily and nocturnal hemodialysis on quality of life, cardiovascular risk and survival

End-stage renal disease (ESRD) is a significant global health problem that places a considerable burden on health care resources. The leading cause of death in ESRD patients is cardiovascular disease, which is often preceded by changes in cardiac geometry, including left ventricular hypertrophy (LVH). Treatments that result in regression of LVH have been shown to lead to better clinical outcomes. Globally, most ESRD patients receive conventional hemodialysis (CHD) 3 times per week, but mortality rates remain high and quality of life (QoL) is poor. Increasing the frequency of HD to 5 or 6 times per week, either as short daily HD (SDHD) or nocturnal HD (NHD), can improve QoL, reduce cardiovascular risk and prolong survival, compared with CHD. Improvements in these end points are likely driven by enhancements in fluid management, blood pressure control, mineral metabolism and left ventricular mass regression. From a practical standpoint, SDHD and NHD are best delivered at home. Barriers to adoption of home HD are chiefly modifiable, and may include lack of a care partner or family support, fear of cannulation and access disconnection, and uncertainty in one's ability to learn the procedures required to perform self-HD. On a positive note, substantial progress has been made to overcome these and other perceived barriers.

Early predictors of cardiac decompensation in experimental volume overload

In humans, volume overload (VOL) increases the risk of sudden cardiac death, but there is also important inter-individual variability, presumably because of differences in genetic backgrounds. Although VOL has rapid effects on myocardial properties, it is not known to which extent the severity of these early responses correlate with the effect of sustained VOL on mortality. In order to test this question, we induced VOL in male rats from two genetically distinct strains [i.e., Sprague-Dawley (SD) and Wistar Kyoto-derived Hyperactive (WKHA) rats] by creating a surgical aorto-caval fistula (ACF). Only 36% of SD rats remained alive after 39 weeks of ACF, in contrast to 82% of the operated WKHA rats. We also monitored myocardial hemodynamic function, mitochondrial properties, left ventricular (LV) morphology and LV wall diastolic properties at different times ranging from 2 to 12 weeks after either ACF or sham surgery. ACF had a rapid impact on the LV walls of both rat strains, but the only variables that were affected to a greater extent in the mortality-prone SD strain were normalized LV weight, LV cavity area, and myocardial wall stiffness. In contrast, there were only marginal strain-related differences in the way ACF affected hemodynamic and mitochondrial functions. Thus, while early morphologic responses of LV walls to ACF (along with their downstream consequences on myocardial diastolic wall stress) correlated well with strain-dependent differences in late mortality, other functional changes showed no predictive effects. Close monitoring of early changes in cardiac geometry (as well as new methods to analyze myocardial diastolic strain) might, therefore, be helpful to further improve risk stratification in humans with volume overload cardiopathies.

Clinical Summaries

Clinical Summaries

Reversibility of Cardiac Abnormalities in Morbidly Obese Adolescents

The purpose of this study was to evaluate changes in cardiac geometry, systolic and diastolic function before and after weight loss in morbidly obese adolescents. Cardiac abnormalities are present in morbidly obese adolescents; however, it is unclear if they are reversible with weight loss. Data from 38 adolescents (13 to 19 years; 29 females, 9 males, 33 Caucasians, 5 African Americans) were evaluated before and after bariatric surgery. Left ventricular mass (LVM), left ventricular (LV) geometry, systolic and diastolic function were assessed by echocardiography. Mean follow up was 10 +/- 3 months. Weight and body mass index decreased post-operatively (mean weight loss 59 +/- 15 kg, pre-operative body mass index 60 +/- 9 kg/m(2) vs. follow-up 40 +/- 8 kg/m(2), p < 0.0001). Change in LVM index (54 +/- 13 g/m(2.7) to 42 +/- 10 g/m(2.7), p < 0.0001) correlated with weight loss (r = 0.41, p = 0.01). Prevalence of concentric left ventricular hypertrophy (LVH) improved from 28% at pre-operative to only 3% at follow up (p = 0.007), and normal LV geometry improved from 36% to 79% at follow up (p = 0.009). Diastolic function also improved (mitral E/Ea lateral 7.7 +/- 2.3 at pre-operative vs. 6.3 +/- 1.6 at post-operative, p = 0.003). In addition, rate-pressure product improved suggesting decreased cardiac workload (p < 0.001). Elevated LVM index, concentric LVH, altered diastolic function, and cardiac workload significantly improve following surgically induced weight loss in morbidly obese adolescents. Large weight loss due to bariatric surgery improves predictors of future cardiovascular morbidity in these young people.

Cardiovascular Pathophysiology of Obesity

The INTERHEART study has recently led to the consideration of visceral obesity as an independent risk factor for cardiovascular diseases. The high rate of morbidity and mortality in obese patients recognises metabolic, haemodynamic, endothelial and endocrine mechanisms as influencing factors. Insulin resistance and the resulting hyperinsulinaemia represents one of the most relevant elements for developing visceral obesity, which is involved in volume overload, sympathetic hyperactivity, increased vascular sensitivity and tone, stable hypertension, left ventricular hypertrophy and atherogenic dyslipidaemia. On the other hand, hypertension, hyperinsulinaemia, and sympathetic and renin-angiotensin hyperactivity may promote the structural changes in cardiac geometry, defined as remodelling, concentric and eccentric hypertrophy, and diastolic and systolic dysfunction and failure. In this view, the adipose tissue has to be considered not only as a deposit tissue, but also as an endocrine organ. Several molecules produced by adipocytes act by an endocrine, paracrine and autocrine function on different tissues. Leptin, adiponectin, tumour necrosis factor-α and interleukin-6 are some of these molecules, which are involved in glucose and lipid metabolism in the atherosclerosis process and in thrombosis and haemodynamic homeostasis.