Contribution of central adiposity to left ventricular diastolic function (from the Baltimore Longitudinal Study of Aging)

Association of cardiometabolic and triglyceride-glucose index with left ventricular diastolic function in asymptomatic individuals

BACKGROUND AND AIMS

Obesity and insulin resistance are associated with left ventricular diastolic dysfunction (LVDD) and increased risk of heart failure. Cardiometabolic index (CMI) and triglyceride glucose (TyG) are new indexes to assess visceral obesity and insulin resistance, respectively. The study aimed to investigate the clinical usefulness of these indexes for identifying LVDD individuals.

METHODS AND RESULTS

Overall, 1898 asymptomatic individuals were included in this cross-sectional study. Participants underwent anthropometrics, serum biochemical evaluation, and echocardiography. Multiple linear regression analysis revealed that both indexes were independent determinants of diastolic parameters among females; while for males, CMI and TyG were not associated with A velocity. In the multivariate logistic analysis, the proportion of LVDD in the third and fourth quartiles of CMI remained significantly greater than that in the lowest quartile in females (Q3 vs. Q1: odds ratio (OR) = 2.032, 95% confidence interval (CI): 1.181-3.496; Q4 vs. Q1: OR = 2.393, 95% CI: 1.347-4.249); while in males, the incidence of LVDD was significantly greater only in the fourth quartile. For TyG, the presence of LVDD in the fourth quartile was significantly greater in both genders. The discriminant values between the CMI (AUC: 0.704, 95% CI: 0.668-0.739) and TyG (AUC: 0.717, 95% CI: 0.682-0.752) were similar in females. Both indexes performed better in females than in males to identify LVDD.

CONCLUSION

The CMI and TyG might both serve as effective tools to identify LVDD in routine health check-ups in primary care, mainly in females. With simpler parameters, the CMI could be utilized in medically resource-limited areas.

Prevalence, Associated Factors, and Echocardiographic Estimation of Left Atrial Hypertension in Patients With Atrial Fibrillation

Background Elevated left atrial (LA) pressure predisposes individuals to the initiation and persistence of atrial fibrillation (AF), and LA hypertension is associated with AF recurrence after catheter ablation (CA). However, the exact frequency and factors associated with LA hypertension are unknown, and its noninvasive estimation is challenging. This study aimed to investigate the prevalence and determinants of LA hypertension in patients with AF who underwent first CA. Methods and Results We examined 183 patients with AF who underwent conventional and speckle-tracking echocardiography before CA to assess LA size, reservoir strain, and stiffness. Direct LA pressure was measured at the time of CA, and LA hypertension was defined as mean LA pressure >15 mm Hg. Thirty-three (18.0%) patients exhibited LA hypertension. Patients with LA hypertension had a significantly larger LA volume index (40.2 [28.4-52.1] versus 34.1 [26.9-42.4] mL/m2, P=0.025), reduced LA reservoir strain (15.1 [10.4-21.7] versus 22.7 [14.4-32.3] %, P=0.002) and increased LA stiffness (0.69 [0.34-0.99] versus 0.36 [0.24-0.54], P<0.001). Multivariable analyses showed that waist circumference, C-reactive protein level, LA reservoir strain, and LA stiffness were independently associated with LA hypertension (all P<0.05), while LA volume and E/e' ratio were not. Among echocardiographic parameters, receiver operating characteristic curve analysis identified LA stiffness as the best predictor of LA hypertension. Conclusions Approximately 20% of patients with AF who underwent CA had LA hypertension. Central obesity and inflammation might be involved in the pathophysiological mechanisms of LA hypertension, and echocardiography-derived LA stiffness may have clinical utility for the detection of LA hypertension before CA.

Crossroads between Estrogen Loss, Obesity, and Heart Failure with Preserved Ejection Fraction

The prevalence of obesity and heart failure with preserved ejection fraction (HFpEF) increases significantly in postmenopausal women. Although obesity is a risk factor for left ventricular diastolic dysfunction (LVDD), the mechanisms that link the cessation of ovarian hormone production, and particularly estrogens, to the development of obesity, LVDD, and HFpEF in aging females are unclear. Clinical, and epidemiologic studies show that postmenopausal women with abdominal obesity (defined by waist circumference) are at greater risk for developing HFpEF than men or women without abdominal obesity. The study presents a review of clinical data that support a mechanistic link between estrogen loss plus obesity and left ventricular remodeling with LVDD. It also seeks to discuss potential cell and molecular mechanisms for estrogen-mediated protection against adverse adipocyte cell types, tissue depots, function, and metabolism that may contribute to LVDD and HFpEF.

Impact of the distribution of epicardial and visceral adipose tissue on left ventricular diastolic function

Although epicardial adipose tissue (EAT) and abdominal visceral adipose tissue (VAT) can contribute to left ventricular diastolic dysfunction (LVDD), the impact of these distribution has not been fully understood. A total of 235 patients who underwent cardiac computed tomography angiography and Doppler echocardiography was included in this study. We evaluated the association of indexed EAT volume and VAT area with septal and lateral early diastolic mitral annular velocity (e'). The VAT area index was significantly associated with septal and lateral e' velocity after adjusted for conventional cardiovascular risk factors and obstructive coronary artery disease (β-estimate; - 0.015 and - 0.019, both p = 0.01). The natural logarithmic EAT volume index (ln EAT volume index) also showed a significant association with septal and lateral e' (β-estimate; - 1.72 and - 0.99, both p < 0.01). The significant association of ln EAT volume index with septal and lateral e' was observed even after adjusting for VAT area index (β-estimate; - 0.79 and - 1.52, both p < 0.03). In the subgroup analysis, there were significant association of ln EAT volume index with both septal and lateral e' in the lower VAT group (β-estimate; - 1.40 and - 1.53, both p < 0.03) and with lateral e' in the higher VAT group (β-estimate - 1.64, p = 0.006). In contrast, ln EAT volume index was not associated with septal e' in the higher VAT group (p = 0.98). EAT accumulation was significantly associated with LVDD independently of obstructive coronary artery disease and abdominal VAT. The impact of EAT on LVDD may vary depending on the amount of abdominal VAT.

The patterns of left ventricular alteration by adipose tissue distribution: implication for heart failure prevention

AIMS

The current study aimed to evaluate the associations between general and abdominal obesity with left ventricular (LV) structure and function and whether these associations differed by sex.

METHODS AND RESULTS

This is a community-based cross-sectional study, and 971 hypertensive individuals without overt cardiovascular disease were included. General obesity was defined as body mass index (BMI) ≥ 28 kg/m² , and abdominal obesity was defined as waist circumference (WC) ≥ 90 cm for men and ≥85 cm for women. The associations between general and abdominal obesity with LV structure and function were examined using linear regression analysis, and the interaction by sex was performed. The mean age was 66.5 ± 11.4 years, and women accounted for 62%. General obese individuals (n = 205) were more likely to have concentric remodelling, LV hypertrophy, and worse diastolic function. Similar differences were observed in abdominal obese individuals (n = 593). General obesity was associated with LV end-diastolic volume, LV mass, left atrial volume, and septal E/e' ratio after adjusting for WC and clinical covariates; and abdominal obesity was associated with septal e' velocity after adjusting for BMI and clinical covariates. The associations between general obesity with LV structure and function did not differ by sex, while the magnitudes of the associations between abdominal obesity with LV mass and septal e' velocity were greater in men.

CONCLUSIONS

General and abdominal obesity were associated with different patterns of LV structural and functional alterations, stressing the importance of incorporating BMI and WC measurements into assessing obesity-related LV alterations.

Prevalence of obesity and an interrogation of the correlation between anthropometric indices and blood pressures in urban Lagos, Nigeria

Adverse cardiovascular outcomes are linked to higher burden of obesity and hypertension. We conducted a secondary analysis of data for 5135 participants aged ≥ 16 years from our community-based hypertension prevalence study to determine the prevalence of obesity and association between multiple anthropometric indices and blood pressure (BP). The indices were waist circumference (WC), body mass index (BMI), waist-to-height ratio (WHtR), waist-to-hip ratio (WHR), a body shape index(ABSI), abdominal volume index (AVI), body adiposity index (BAI), body roundness index (BRI), visceral adiposity index (VAI) and conicity index (CI). We performed statistical analyses to determine the association, predictive ability, cutoff values and independent determinants of hypertension. Crude prevalence of obesity was 136 per 1000 (95% confidence interval 126-146). BMI had the strongest correlation with systolic and diastolic BP (r_s = 0.260 and 0.264, respectively). Indices of central adiposity (AVI, WC, WHtR, BRI) were the strongest predictors of hypertension (≥ 140/90 mmHg), and their cut-off values were generally higher in females than males. WHR, age, BMI and CI were independent determinants of hypertension ≥ 140 mmHg (p < 0.05). We conclude that, based on this novel study, measures of central adiposity are the strongest predictors and independent determinants of hypertension in our population, and cut-off values vary from previously recommended standards.

Impact of Pulse Wave Velocity and Parameters Reflecting Android Type Fat Distribution on Left Ventricular Diastolic Dysfunction in Patients with Chronic Coronary Syndromes

Background: Left ventricular diastolic dysfunction (LVDD) is caused by a decreased left ventricle relaxation and is associated with an increased risk of symptomatic heart failure (HF) and excessive mortality. Aim: To evaluate the frequency and factors related to LVDD in the population with chronic coronary syndromes (CCS). Methods: 200 patients (mean age 63.18 ± 8.12 years, 75.5% male) with CCS were included. LVDD was diagnosed based on the recent echocardiography guidelines. Results: LVDD was diagnosed in 38.5% of CCS population. From the studied factors, after adjustment for age, sex, and N-terminal pro-brain natriuretic peptide (NT-proBNP), LVDD associated positively with android/gynoid (A/G) fat mass ratio, left ventricular mass index (LVMI), and negatively with Z-score and left ventricular ejection fraction (LVEF). In stepwise backward logistic regression analysis, the strongest factors associated with LVDD were pulse wave velocity value, handgrip strength and waist to hip ratio (WHR). Conclusions: LVDD is common among CCS patients and it is associated with parameters reflecting android type fat distribution regardless of NT-proBNP and high-sensitivity troponin T concentrations. Deterioration in diastolic dysfunction is linked with increased aortic stiffness independently of age and sex. Further studies evaluating the effects of increasing physical fitness and lowering abdominal fat accumulations on LVDD in CCS patients should be considered.

Associations of region-specific visceral adiposity with subclinical atrial dysfunction and outcomes of heart failure

AIMS

Excessive visceral adiposity (VAT) plays an essential role in metabolic derangements with those close to heart further mediates myocardial homeostasis. The disparate biological links between region-specific VAT and cardiometabolic profiles as mediators influencing atrial kinetics remain unexplored.

METHODS AND RESULTS

Among 1326 asymptomatic individuals, region-specific VAT including peri-aortic root fat (PARF) and total pericardial fat (PCF) of cardiac region, together with thoracic peri-aortic adipose tissue (TAT), was assessed using multiple-detector computed tomography. VAT measures were related to functional left atrial (LA) metrics assessed by speckle-tracking algorithm and clinical outcomes of atrial fibrillation (AF) and heart failure (HF). Multivariate linear regression models incorporating body fat, metabolic syndrome, and E/TDI-e' consistently demonstrated independent associations of larger PARF/PCF with peak atrial longitudinal systolic strain (PALS) reduction, higher LA stiffness, and worsened strain rate components; instead, TAT was independently associated with cardiometabolic profiles. PARF rather than PCF or TAT conferred independent prognostic values for incident AF/HF by multivariate Cox regression (adjusted hazard ratio: 1.56, 95% confidence interval: 1.17-2.08, P = 0.002) during a median of 1790 days (interquartile range: 25th to 75th: 1440-1927 days) of follow-up, with subjects categorized into worst PALS and largest VAT tertiles demonstrating highest events (all log-rank P < 0.001). Mediation analysis showed that higher triglyceride and lower high-density lipoproteins may serve as intermediary factors for effects between VAT and LA functional metrics, with lesser role by glucose level.

CONCLUSIONS

Visceral adiposity surrounding atrial region was tightly associated with subclinical atrial dysfunction and incident AF or HF beyond metabolic factors. Instead, peri-aortic adiposity may mediate their toxic effects mainly through circulating cardiometabolic profiles.

Metabolic Risk Factors and Left Ventricular Diastolic Function in Middle-Aged Chinese Living in the Tibetan Plateau

Background

Data regarding the metabolic risk factors clustering on the risk of left ventricular diastolic dysfunction (LVDD) are lacking among people living at high altitude and under hypoxic conditions. In this study, we explored the association between metabolic risk factor clustering and LVDD among the Tibetan population of China.

Methods and Results

We conducted a cross‐sectional survey in a representative sample of 1963 Tibetans in 2014 to 2016. Grading LVDD was based on recommendations for the evaluation of LV diastolic function by echocardiography (2009). The prevalence of LVDD among 1963 participants (mean age: 51.51 years, 41.11% male) was 34.39%. Odds ratios (95% CI) of LVDD for the 1, 2, and 3 to 5 risk factors clustering were 1.45 (0.96–2.17), 2.68 (1.8–3.98), and 2.9 (1.9–4.43), respectively (P for trend <0.001). The association between metabolic risk factors clustering and LVDD was much more pronounced in the middle‐aged group than in the elderly (P for interaction=0.0170). High altitude was one of the major independent risk factors for LVDD; however, habitation altitude had no significant effect on the association between metabolic risk factors and LVDD (P for interaction=0.1022). The multivariable dominance analysis indicated that abdominal obesity, hypertension, and elevated blood glucose were the significant contributors to LVDD.

Conclusions

There was a significant positive association between the metabolic risk factor clustering number and LVDD among a population living at high altitude, especially in middle‐aged adults. However, habitation altitude itself has no significant effect on the association between metabolic risk factors and LVDD.

Prevalence and determinants of left ventricular diastolic dysfunction in obese subjects and the role of left ventricular global longitudinal strain and mass normalized to height

BACKGROUND

Left ventricular (LV) diastolic dysfunction (DD) is a frequent finding in obesity and may predispose to the development of heart failure (HF). However, no data are available on the prevalence of DD after the introduction of the 2016 Recommendations of the American Society of Echocardiography and the European Association of Cardiovascular Imaging.

METHODS AND RESULTS

To assess the impact of the new Recommendations on the prevalence of DD and on their clinical and echocardiographic correlates in obesity, a prospective study was performed in 588 subjects with an ejection fraction (EF) ≥50% and no history of HF either obese (n = 402; mean age: 47 ± 12 years; women 71%; body mass index [BMI]: 44 ± 8 kg/m² ), overweight (n = 86; BMI: 28 ± 1 kg/m² ), or with a normal weight (n = 100; BMI: 22 ± 2 kg/m² ). All subjects underwent an echocardiographic and Doppler study, including the assessment of global longitudinal strain (GLS). DD occurred in 19% of obese patients, 12% of overweight subjects, and 2% of normal weight subjects. We used multivariable logistic analysis to assess the risk of DD. In patients with BMI ≥30 kg/m² , LV mass normalized to height (2.7) (OR: 1.04, P = .0028), and GLS (OR: 0.85, P = .0032) were associated with an increased risk of DD followed by EF (OR: 0.91, P = .045), diabetes (OR: 1.91, P = .065), and systolic blood pressure (OR: 1.02, P = .076).

CONCLUSION

These results show that DD is highly prevalent among obese subjects and impairment of longitudinal systolic mechanics, as reflected by GLS reduction, and LV mass normalized to height are major independent predictors of DD in this patients' population.

Adiposity, body composition and ventricular-arterial stiffness in the elderly: the Atherosclerosis Risk in Communities Study

AIM

Weight gain appears to accelerate age-related ventricular-arterial stiffening, which has been implicated in the development of heart failure (HF), but it is unclear whether body fat accumulation underpins this association. We evaluated the relationship of adiposity, using measures of body composition, with ventricular-arterial stiffness among the elderly in the community.

METHODS AND RESULTS

Adiposity was accessed through body mass index (BMI), waist circumference, and body fat percentage. We studied the association of these measures with carotid-femoral pulse wave velocity (cfPWV), arterial elastance index (EaI), left ventricular (LV) end-systolic elastance index (EesI) and LV end-diastolic elastance index (EedI) in 5520 community-based, elderly Atherosclerosis Risk in Communities (ARIC) Study participants, who underwent echocardiography between 2011 and 2013. BMI and waist circumference were directly associated with EaI, EedI and EesI even after adjusting for age, sex, race, hypertension, diabetes mellitus, heart rate, prevalent coronary heart disease and HF. After further adjustment for BMI, body fat percentage demonstrated significant independent linear relationships with EaI [standardized beta coefficient (β)=0.17, P<0.001], EesI (β=0.08, P=0.003) and EedI (β=0.20, P<0.001), and significant non-linear relationships with cfPWV (P=0.033).

CONCLUSION

In this biracial community-based cohort, increased adiposity was associated with increased ventricular-arterial stiffness among the elderly and suggests a potential mechanism by which obesity might contribute to the development of HF.

Association of Central Adiposity With Adverse Cardiac Mechanics: Findings From the Hypertension Genetic Epidemiology Network Study

BACKGROUND

Central obesity, defined by increased waist circumference or waist:hip ratio (WHR), is associated with increased cardiovascular events, including heart failure. However, the pathophysiological link between central obesity and adverse cardiovascular outcomes remains poorly understood. We hypothesized that central obesity and larger WHR are independently associated with worse cardiac mechanics (reduced left ventricular strain and systolic [s'] and early diastolic [e'] tissue velocities).

METHODS AND RESULTS

We performed speckle-tracking analysis of echocardiograms from participants in the Hypertension Genetic Epidemiology Network (HyperGEN) study, a population- and family-based epidemiological study (n=2181). Multiple indices of systolic and diastolic cardiac mechanics were measured. We evaluated the association between central obesity and cardiac mechanics using multivariable-adjusted linear mixed-effects models to account for relatedness among participants. The mean age of the cohort was 51±14 years, 58% were women, and 47% were black. Mean body mass index was 30.8±7.1 kg/m(2), waist circumference was 102±17 cm, WHR was 0.91±0.08, and 80% had central obesity based on waist circumference and WHR criteria. After adjusting for multiple potential confounders (including age, sex, race, physical activity, body mass index, heart rate, smoking status, systolic blood pressure, fasting glucose, total cholesterol, antihypertensive medication use, glomerular filtration rate, left ventricular mass index, wall motion abnormalities, and ejection fraction), central obesity and WHR remained associated with worse global longitudinal strain, early diastolic strain rate, s' velocity, and e' velocity (P<0.05 for all comparisons). There were no significant statistical interactions between WHR and obesity status.

CONCLUSIONS

In this cross-sectional study of participants with multiple comorbidities, central obesity was found to be associated with adverse cardiac mechanics.

Investigating the differences of body mass index and waist circumference in the follow-up assessment of patients to cardiac rehabilitation with acute coronary syndrome

Obesity management is a key point during cardiac rehabilitation. The effect of new index, waist circumference (WC), in the obesity management of cardiac rehabilitation is not clear yet. Therefore, our study compared the WC index to the body mass index (BMI) in the evaluation of obesity management for the patients with acute coronary syndrome (ACS) in a well-designed cardiac rehabilitation program (CRP). Totally 61 patients were enrolled into our study between October 2013 and January 2014 in our hospital. All these patients were requested to participate in the CRP actively for 6 months. We collected the BMI, WC, vital signs, fasting blood levels, the results from a sub-maximal exercise treadmill test (ETT) and ultrasonic cardiogram (UCG) through a follow-up visit conducted every 1, 3, and 6 months. We used two-tailed Pearson's test and linear regression to analyze the data from our experiment. Our results show that the grouping of obese individuals based on the WC results in the WC being significantly associated with high-density lipoprotein cholesterol (HDL_C), inter-ventricular septal thickness at diastole (IVSd) and left ventricular posterior wall at diastole (LVPwd) after 1 and 3 months of the CRP (HDL_C after1 month of CRP: r = -0.292, P = 0.022; HDL_C after 3 months of CRP: r = -0.289, P = 0.024; IVSd after1 month of CRP: r = 0.451, P = 0.004; IVSd after 3 months of CRP: r = 0.304, P = 0.035; LVPwd after1 month of CRP: r = 0.468, P = 0.002; LVPwd after 3 months of CRP: r = 0.290, P = 0.045). However, no similar regular associations were found when obesity was stratified using the BMI. In other words, WC could be better than the BMI for reflecting the cardiac status. In conclusion, obesity management using WC can benefit the clinical evaluation, diagnosis, treatment, prevention, and prognosis of obese individuals of ACS when participating in the CRP.

Early menopause does not influence left ventricular diastolic dysfunction: A clinical observational study in healthy subjects

BACKGROUND

The prevalence of left ventricular diastolic dysfunction (LVDD) sharply increases in women after their 50s and may contribute to the high prevalence of diastolic heart failure in elderly women. A decrease in estrogen levels after menopause is postulated to be one of the mechanisms responsible for this phenomenon. However, there is a paucity of data on the relationship between the timing of menopause and the progression of LVDD in the clinical setting; thus, we investigated this relationship in healthy postmenopausal women.

METHODS

We enrolled 115 women and divided them into two groups according to median menopause age: 61 who experienced menopause at ≤50 years (early menopause group), and 54 who experienced menopause at >50 years (late menopause group). We compared the echocardiographic and clinical characteristics between the two groups.

RESULTS

There were no significant differences in LV diastolic parameters (mitral E/A, p=0.561; e', p=0.052; E/e', p=0.081; DCT, p=0.082; prevalence of LVDD class, p=0.801), as well as other echocardiographic parameters and clinical characteristics between the two groups. Multivariate linear regression analysis showed that the independent determinants of LVDD were age and body mass index, but not the timing of menopause.

CONCLUSIONS

Early menopause did not influence the progression of LVDD in postmenopausal women. The sharp progression of LVDD in elderly women is complex and probably influenced by multiple factors.

Coronary microvascular function is independently associated with left ventricular filling pressure in patients with type 2 diabetes mellitus

BACKGROUND

Left ventricular (LV) diastolic dysfunction is known as an early marker of myocardial alterations in patients with diabetes. Because microvascular disease has been regarded as an important cause of heart failure or diastolic dysfunction in diabetic patients, we tested the hypothesis that coronary flow reserve (CFR), which reflects coronary microvascular function, is associated with LV diastolic dysfunction in patients with type 2 diabetes.

METHODS

We studied asymptomatic patients with type 2 diabetes but without overt heart failure. Transthoracic Doppler echocardiography was performed that included pulsed tissue Doppler of the mitral annulus and CFR of the left anterior descending artery (induced by adenosine 0.14 mg/kg/min). The ratio of mitral velocity to early diastolic velocity of the mitral annulus (E/e') was used as a surrogate marker of diastolic function. We also evaluated renal function, lipid profile, parameters of glycemic control and other clinical characteristics to determine their association with E/e'. Patients with LV ejection fraction <50%, atrial fibrillation, valvular disease, regional wall motion abnormality, renal failure (serum creatinine >2.0 mg/dl) or type 1 diabetes were excluded. Patients with a CFR <2.0 were also excluded based on the suspicion of significant coronary artery stenosis.

RESULTS

We included 67 asymptomatic patients with type 2 diabetes and 14 non-diabetic controls in the final study population. In univariate analysis, age, presence of hypertension, LV mass index, estimated glomerular filtration rate and CFR were significantly associated with E/e'. Multivariate analysis indicated that both LV mass index and CFR were independently associated with E/e'. In contrast, there were no significant associations between parameters of glycemic control and E/e'.

CONCLUSIONS

CFR was associated with LV filling pressure in patients with type 2 diabetes. This result suggests a possible link between coronary microvascular disease and LV diastolic function in these subjects.

The Different Effects of BMI and WC on Organ Damage in Patients from a Cardiac Rehabilitation Program after Acute Coronary Syndrome

One of the purposes of cardiac rehabilitation (CR) after acute coronary syndrome (ACS) is to monitor and control weight of the patient. Our study is to compare the different obesity indexes, body mass index (BMI), and waist circumference (WC), through one well-designed CR program (CRP) with ACS in Guangzhou city of Guangdong Province, China, in order to identify different effects of BMI and WC on organ damage. In our work, sixty-one patients between October 2013 and January 2014 fulfilled our study. We collected the vital signs by medical records, the clinical variables of body-metabolic status by fasting blood test, and the organ damage variables by submaximal exercise treadmill test (ETT) and ultrasonic cardiogram (UCG) both on our inpatient and four-to-five weeks of outpatient part of CRP after ACS. We mainly used two-tailed Pearson's test and liner regression to evaluate the relationship of BMI/WC and organ damage. Our results confirmed that WC could be more accurate than BMI to evaluate the cardiac function through the changes of left ventricular structure on the CRP after ACS cases. It makes sense of early diagnosis, valid evaluation, and proper adjustment to ACS in CRP of the obesity individuals in the future.

Gender differences in predictors of left ventricular myocardial relaxation in non-obese, healthy individuals

Background

Previous studies indicate that individuals with metabolic syndrome (MetS) might be at risk for left ventricular (LV) diastolic dysfunction. However, little is known about which metabolic factors contribute to the development of LV dysfunction in individuals who are not obese or overweight and who do not have diabetes mellitus and/or cardiovascular disease.

Methods

Participants without diabetes mellitus, systolic dysfunction, or other heart diseases underwent a thorough physical examination, including tissue Doppler echocardiography. A peak early mitral annular velocity (e′) of <5.0 was designated as indicating abnormal LV myocardial relaxation (LVMR). We performed single and multiple logistic regression analyses of e′ and cardiovascular risk factors, including MetS factors and indicators of major organ dysfunction. Normal-weight subjects (body mass index <25 kg/m²) were also analyzed.

Results

A total of 1055 individuals (mean age, 63 ± 13 years) participated, of which 307 (29.1%) had MetS and 199 (18.9%) had abnormal LVMR. Multiple logistic regression analysis revealed waist circumference (WC) (odds ratio [OR] 1.04, P < 0.05) and age (OR 1.10, P < 0.05) to be predictors of abnormal LVMR. In normal-weight subjects (n = 806), aging (OR 1.08, P < 0.01), abnormal WC (OR 3.80, P < 0.01), and renal dysfunction (OR 2.14, P < 0.01) were predictors of abnormal LVMR. Among MetS factors, abnormal WC in men (OR 3.70, P < 0.01) and high diastolic blood pressure (DBP) in women (OR 4.00, P = 0.01) were related to abnormal LVMR.

Heart failure and atrial fibrillation: from basic science to clinical practice

Heart failure (HF) and atrial fibrillation (AF) are two growing epidemics associated with significant morbidity and mortality. They often coexist due to common risk factors and shared pathophysiological mechanisms. Patients presenting with both HF and AF have a worse prognosis and present a particular therapeutic challenge to clinicians. This review aims to appraise the common pathophysiological background, as well as the prognostic and therapeutic implications of coexistent HF and AF.

Diastolic dysfunction in the diabetic continuum: association with insulin resistance, metabolic syndrome and type 2 diabetes

Background

Diabetes increases the risk of heart failure but the underlying mechanisms leading to diabetic cardiomyopathy are poorly understood. Left ventricle diastolic dysfunction (LVDD) is one of the earliest cardiac changes in these patients. We aimed to evaluate the association between LVDD with insulin resistance, metabolic syndrome (MS) and diabetes, across the diabetic continuum.

Methods

Within a population-based study (EPIPorto), a total of 1063 individuals aged ≥45 years (38% male, 61.2 ± 9.6 years) were evaluated. Diastolic function was assessed by echocardiography, using tissue Doppler analysis (E’ velocity and E/E’ ratio) according to the latest consensus guidelines. Insulin resistance was assessed using the Homeostasis Model Assessment of Insulin Resistance (HOMA-IR) score.

Results

The HOMA-IR score correlated to E’ velocity (ρ = −0.20;p < 0.0001) and E/E’ ratio (ρ = 0.20; p < 0.0001). There was a progressive worsening in E’ velocity (p for trend < 0.001) and in E/E’ ratio across HOMA-IR quartiles (p for trend <0.001). Individuals in the highest HOMA-IR quartile were more likely to have LVDD, even after adjustment for age, sex, blood pressure and body mass index (adjusted OR: 1.82; 95% CI: 1.09-3.03). From individuals with no MS, to patients with MS and no diabetes, to patients with diabetes, there was a progressive decrease in E’ velocity (11.2 ± 3.3 vs 9.7 ± 3.1 vs 9.2 ± 2.8 cm/s; p < 0.0001), higher E/E’ (6.9 ± 2.3 vs 7.8 ± 2.7 vs 9.0 ± 3.6; p < 0.0001) and more diastolic dysfunction (adjusted OR: 1.62; 95% CI: 1.12-2.36 and 1.78; 95% CI: 1.09-2.91, respectively).

Conclusions

HOMA-IR score and metabolic syndrome were independently associated with LVDD. Changes in diastolic function are already present before the onset of diabetes, being mainly associated with the state of insulin resistance.

Electronic supplementary material

The online version of this article (doi:10.1186/s12933-014-0168-x) contains supplementary material, which is available to authorized users.

Influence of epicardial and visceral fat on left ventricular diastolic and systolic functions in patients after myocardial infarction

Obesity has been associated with subclinical left ventricular (LV) diastolic dysfunction and increased risk of heart failure. Few data are available on the relative contribution of adiposity distribution and changes in myocardial structure and function. We evaluated the influence of visceral versus subcutaneous abdominal adipose tissue and epicardial fat on LV diastolic function after acute myocardial infarction. One month after acute myocardial infarction, 225 consecutive patients were prospectively enrolled and underwent anthropometric evaluation, bioimpedance analysis, detailed echocardiography, and multidetector 64-slice computed tomography scan for quantification of epicardial fat volume (EFV) and of total, subcutaneous and visceral abdominal fat areas. We found a significant association between LV diastolic dysfunction parameters and body mass index, fat-mass percentage, and waist-to-height ratio. E' velocity and E/E' ratio were correlated with total and visceral abdominal fat (r = -0.27, p <0.001 and r = 0.21, p <0.01, respectively), but not with subcutaneous fat. After multivariate analysis, increasing EFV was associated with decreased E' velocity (adjusted β -0.11, 95% confidence interval -0.19 to -0.03; p <0.01) and increased E/E' ratio (adjusted β 0.19, 95% confidence interval 0.07 to 0.31, p <0.01). Patients with diastolic dysfunction showed higher EFV (116.7 ± 67.9 ml vs 93.0 ± 52.3 ml, p = 0.01), and there was a progressive increase in EFV according to diastolic dysfunction grades (p = 0.001). None of the adiposity parameters correlated with ejection fraction or S' velocities. In conclusion, in patients after myocardial infarction, impaired LV diastolic function was associated with increased adiposity, especially with visceral and central fat parameters. Increasing EFV was independently associated with worse LV diastolic function.

Impact of general and central adiposity on ventricular-arterial aging in women and men

OBJECTIVES

The aim of this study was to assess the effects of central and general obesity measures on long-term longitudinal changes in ventricular-arterial mechanics.

BACKGROUND

Obesity, female sex, and ventricular-arterial stiffening are associated with the development of heart failure with preserved ejection fraction. Fat distribution and chronic changes in body composition may affect longitudinal changes in LV properties, independent of arterial load.

METHODS

In 1,402 subjects from a randomly selected, community-based population, comprehensive echo-Doppler echocardiography was performed at two examinations separated by 4 years. From this population, 788 subjects had paired data adequate for determining left ventricular end-systolic elastance (Ees), end-diastolic elastance (Eed), and effective arterial elastance (Ea).

RESULTS

Over 4 years, Ea was decreased by 3% in tandem with improved blood pressure control, whereas Ees and Eed were increased by 14% and 8% (all, p < 0.001). Greater weight loss over 4 years was associated with progressively greater decreases in Ea in men and women. After adjustment for Ea change, weight gain was correlated with increases in Eed in both women and men. Central obesity was associated with greater age-related increases in Ees in women but not in men, independent of arterial load, but central obesity did not predict changes in Eed or Ea.

CONCLUSIONS

In these subjects, weight gain was associated with increases in LV diastolic stiffness, even after adjustment for changes in arterial afterload, whereas weight loss was associated with reductions in arterial stiffness. Age-related LV systolic stiffening was increased in women, but not in men, with central obesity. Strategies for promoting weight loss and reducing central adiposity may be effective in preventing heart failure with preserved ejection fraction, particularly in women.

Prevalence, clinical correlates, and functional impact of subaortic ventricular septal bulge (from the Baltimore Longitudinal Study of Aging)

A localized hypertrophy of the subaortic segment of the ventricular septum-ventricular septal bulge (VSB)-has been frequently described in series of elderly population, but its prevalence with age, clinical correlates, and impact on cardiac function and exercise capacity remain uncertain. We explored these associations in a cross-sectional sample without known cardiac disease from the Baltimore Longitudinal Study of Aging. We randomly selected 700 participants (50% men, mean age 64 ± 15, range 26 to 95 years) and reviewed their echocardiograms. We identified 28 men and 21 women with VSB (7% overall prevalence). The prevalence of VSB significantly increased with age in both genders (p <0.0001). In multivariate logistic regression including hypertension and other cardiovascular risk factors, only age displayed a significant independent association with VSB (OR 1.06 per year, 95% confidence interval 1.03 to 1.10, p = 0.0001). After multiple adjustments, participants with VSB compared with those without had enhanced global left ventricular contractility (fractional shortening 41 ± 1.3 vs 38 ± 0.3%, p = 0.04; ejection fraction 71 ± 1.6 vs 67 ± 0.4%, p = 0.06; systolic velocity of the mitral annulus 8.4 ± 0.1 vs 8.9 ± 0.3, p = 0.06), and larger aortic root diameters (3.3 ± 0.06 vs 3.1 ± 0.02 cm, p = 0.02). In subgroup of participants who completed a maximal treadmill test (177 women and 196 men), those with VSB (19, 5.1%) had significantly lower peak oxygen consumption than their counterparts (19.6 ± 3.8 vs 22.9 ± 6.6 ml/kg/min, p = 0.03). However, this association was no longer significant after multiple adjustments. In conclusion, the presence of VSB is independently associated with older age and determines enhanced left ventricular contractility, without any evident impact on exercise capacity.

Is obesity predictive of cardiovascular dysfunction independent of cardiovascular risk factors?

INTRODUCTION

Obesity is thought to exert detrimental effects on the cardiovascular (CV) system. However, this relationship is impacted by the co-occurrence of CV risk factors, type 2 diabetes (T2DM) and overt disease. We examined the relationships between obesity, assessed by body mass index (BMI) and waist circumference (WC), and CV function in 102 subjects without overt CV disease. We hypothesized that obesity would be independently predictive of CV remodeling and functional differences, especially at peak exercise.

METHODS

Brachial (bSBP) and central (cSBP) systolic pressure, carotid-to-femoral pulse wave velocity (PWVcf) augmentation index (AGI; by SphygmoCor), and carotid remodeling (B-mode ultrasound) were examined at rest. Further, peak exercise cardiac imaging (Doppler ultrasound) was performed to measure the coupling between the heart and arterial system.

RESULTS

In backward elimination regression models, accounting for CV risk factors, neither BMI nor WC were predictors of carotid thickness or PWVcf; rather age, triglycerides and hypertension were the main determinants. However, BMI and WC predicted carotid cross-sectional area and lumen diameter. When examining the relationship between body size and SBP, BMI (β=0.32) and WC (β=0.25) were predictors of bSBP (P<0.05), whereas, BMI was the only predictor of cSBP (β=0.22, P<0.05) indicating a differential relationship between cSBP, bSBP and body size. Further, BMI (β=-0.26) and WC (β=-0.27) were independent predictors of AGI (P<0.05). As for resting cardiac diastolic function, WC seemed to be a better predictor than BMI. However, both BMI and WC were inversely and independently related to arterial-elastance (net arterial load) and end-systolic elastance (cardiac contractility) at rest and peak exercise.

CONCLUSION

These findings illustrate that obesity, without T2DM and overt CV disease, and after accounting for CV risk factors, is susceptible to pathophysiological adaptations that may predispose individuals to an increased risk of CV events.

The association between leptin and depressive symptoms is modulated by abdominal adiposity

BACKGROUND

Evidence for a role of leptin in depression is limited and conflicting. Inconclusive findings may be explained by the complex effect of obesity on leptin signaling. In particular, both hyperleptinemia due to leptin resistance in obese persons as well as low leptin in lean persons can imply that low leptin biological signaling is associated with an increased risk of significant depressive symptoms. We tested whether the relationship between leptin and depressive symptoms is modulated by abdominal adiposity in two population-based studies.

METHODS

Data were from 851 participants (65-94 years) of the InCHIANTI Study and 1064 (26-93 years) of the Baltimore Longitudinal Study of Aging (BLSA). Plasma concentrations of leptin, waist circumference and depressive symptoms via the Center for Epidemiological Studies-Depression scale (CES-D) were assessed. In longitudinal InCHIANTI analyses onset of depressed mood (CES-D≥20) was evaluated over a 9-year follow-up.

RESULTS

In pooled cross-sectional analyses the interaction between leptin and waist circumference was significantly associated with CES-D scores ((log)leptin-by-waist interaction p=0.01). Also in longitudinal analyses, the (log)leptin-by-waist interaction term significantly (p=0.04) predicted depressed mood onset over time; depressed mood risk was especially increased for high levels of both leptin and waist circumference.

CONCLUSIONS

The present findings suggest that low leptin signaling rather than low leptin concentration is a risk factor for depression. Future studies should develop proxy measures of leptin signaling by combining information on abdominal adiposity and leptin level to be used for clinical and research applications.

The relationship between visceral adiposity and left ventricular diastolic function: results from the Baltimore Longitudinal Study of Aging

BACKGROUND AND AIMS

It is unclear whether subcutaneous and visceral fat are differentially correlated to the decline in left ventricular (LV) diastolic function with aging. This study sought to examine the hypothesis that age-related changes in the regional fat distribution account for changes in LV diastolic function and to explore potential mediators of this association.

METHODS AND RESULTS

In this cross-sectional study, we evaluated 843 participants of the Baltimore Longitudinal Study of Aging with echocardiogram, dual-energy X-ray absorptiometry (DEXA), abdominal computed tomography (CT) and blood tests performed at the same visit. LV diastolic function was assessed by parameters of LV relaxation (E/A ratio, Em and Em/Am ratio) and LV filling pressures (E/Em ratio). Total body fat was computed by DEXA, while visceral and subcutaneous fat were determined from abdominal CT. In multivariate models adjusted for demographics, cardiovascular risk factors, antihypertensive medications, physical activity and LV mass, both visceral and subcutaneous fat were associated with LV diastolic dysfunction. When both measures of adiposity were simultaneously included in the same model, only visceral fat was significantly associated with LV diastolic dysfunction. Triglycerides and sex-hormone binding globulin, but not adiponectin and leptin, were found to be significant mediators of the relationship between visceral fat and LV diastolic function, explaining 28-47% of the association. Bootstrapping analyses confirmed the significance of these findings.

CONCLUSIONS

Increased visceral adiposity is associated with LV diastolic dysfunction, possibly through a metabolic pathway involving blood lipids and ectopic fat accumulation rather than adipokines.

New echocardiographic techniques in the evaluation of left ventricular function in obesity

OBJECTIVE

Obesity has reached global epidemic proportions and is associated with numerous comorbidities, including major cardiovascular (CV) diseases.

DESIGN AND METHODS

It has many adverse effects on hemodynamics and CV structure and function: it increases total blood volume and cardiac output, and the cardiac workload is greater. Typically, obese patients have a higher cardiac output but a lower level of total peripheral resistance at any given level of arterial pressure. Most of the increase in cardiac output in obesity is caused by stroke volume, although heart rate typically mildly increases also due to enhanced sympathetic activation.

RESULTS

Over the last few years, experimental investigations have unraveled some important pathogenetic mechanisms that may underlie a specific form of "obesity cardiomyopathy." Bariatric surgery represents an effective alternative to treat obesity when nonsurgical weight loss programs (diet + behavior modifications + regular exercise) have failed. A great numbers of questions are still open in the global comprehension of the pathophysiological interactions between obesity and heart.

CONCLUSION

Conventional two-dimensional Doppler echocardiography, integrated by relative new technological ultrasonic approaches, represents the reference technique to study and possibly clarify both the very complex hemodynamic changes induced by obesity and those relative to obesity treatment.

Influencing factors on cardiac structure and function beyond glycemic control in patients with type 2 diabetes mellitus

BACKGROUND

We hypothesized that clinical factors other than glycemic control may influence abnormal cardiac function in patients with type 2 diabetes mellitus (T2DM). We aimed to investigate the independent factors for abnormal cardiac function among clinical factors in T2DM.

METHODS

We studied 148 asymptomatic patients with T2DM without overt heart disease. Echocardiographic findings were compared between diabetic patients and 68 age-matched healthy subjects. Early (E) and late (A) diastolic mitral flow velocity and early diastolic mitral annular velocity (e') were measured for assessing left ventricular (LV) diastolic function. We evaluated insulin resistance, non-esterified fatty acid, high-sensitive CRP, estimated glomerular filtration rate, waist/hip ratio, abdominal visceral adipose tissue (VAT), subcutaneous adipose tissue (SAT) and other clinical characteristics in addition to glycemic control. VAT and SAT were quantified by computed tomography.

RESULTS

In T2DM, E/A and e' were significantly lower, and E/e', left atrial volume and LV mass were significantly greater than in control subjects. In multivariate liner regression analysis, VAT was an independent determinant of left atrial volume (β =0.203, p=0.011), E/A (β =-0.208, p=0.002), e' (β =-0.354, p<0.001) and E/e' (β=0.220, p=0.003). Age was also an independent determinant, whereas fasting plasma glucose and hemoglobin A1c levels were not. In addition to systolic blood pressure, waist-hip ratio (β=0.173, p=0.024) and VAT/SAT ratio (β=0.162, p=0.049) were independent determinants of LV mass.

CONCLUSION

Excessive visceral fat accompanied by adipocyte dysfunction may play a greater role than glycemic control in the development of diastolic dysfunction and LV hypertrophy in T2DM.

Impact of overweight and obesity on left ventricular diastolic function and value of tissue Doppler echocardiography

Background

Diastolic dysfunction is a common cause of heart failure with preserved systolic function in obese patients.

Objective

To assess diastolic function in a series of overweight and obese patients using conventional and tissue Doppler echocardiography.

Setting and method

University hospital; left ventricular diastolic function was evaluated in 99 patients (mean age 61.59 ± 13.9 years); body mass index and waist circumference were assessed, and patients were subdivided into three groups according to their body mass index (kg/m²): [normal, (18.5–24.9); overweight, (25–29.9); obese, (>29.9)]. Peak early (E) and late (A) transmitral flow and peak early (E′) diastolic mitral annulus velocities were measured.

Results

Diastolic dysfunction was significantly higher in the overweight/obese groups compared to the normal body mass index group. The analysis was made with regard to waist circumference and other clinical characteristics, and multivariate regression analysis showed a direct and independent effect of body mass index on diastolic function [OR: 2.75; CI: 1.34–5.67; P = 0.006]. Discussion was made in view of the latest clinical data. Also, an insight into normal weight obesity is presented and discussed.

Conclusion

Overweight and obesity are found to have an independent negative impact on diastolic function as assessed by tissue Doppler imaging.

Predictors of new-onset heart failure: differences in preserved versus reduced ejection fraction

BACKGROUND

About one half of patients with heart failure (HF) have preserved ejection fraction (HFPEF) rather than reduced ejection fraction (HFREF). The differences in risk factors predisposing to the 2 subtypes of HF are poorly understood. We sought to identify clinical predictors of new-onset HF and to explore differences in HFPEF versus HFREF.

METHODS AND RESULTS

We studied new-onset HF cases between 1981 and 2008 in Framingham Heart Study participants, classified into HFPEF and HFREF (ejection fraction >45% versus ≤45%). We used Cox multivariable regression to examine predictors of 8-year risk of incident HF and competing-risks analysis to identify predictors that differed between HFPEF and HFREF. Among 6340 participants (60±12 years) with 97 808 person-years of follow-up, 512 developed incident HF. Of 457 participants with left ventricular ejection fraction evaluation at the time of HF diagnosis, 196 (43%) were classified as HFPEF and 261 (56%) as HFREF. Fourteen predictors of overall HF were identified. Older age, diabetes mellitus, and a history of valvular disease predicted both types of HF (P≤0.0025 for all). Higher body mass index, smoking, and atrial fibrillation predicted HFPEF only, whereas male sex, higher total cholesterol, higher heart rate, hypertension, cardiovascular disease, left ventricular hypertrophy, and left bundle-branch block predicted risk of HFREF.

CONCLUSIONS

Although multiple risk factors preceded overall HF, distinct clusters of risk factors determine risk for new-onset HFPEF versus HFREF. This knowledge may enable the design of clinical trials of targeted prevention and the introduction of therapeutic strategies for prevention of HF and its 2 major subtypes.