Background

Studies investigating the association between central aortic pressures and diastolic function have been limited.

Methods

Consecutive ambulatory patients (n=281, mean age 49±13 yrs, 49% male) with normal LV systolic function were included. LV filling pressure (E/Em) was estimated by Doppler-derived ratio of mitral inflow velocity [E] to septal [Em] by tissue Doppler, LV relaxation by Em, central aortic pressures by radial tonometry. Central aortic systolic (cSBP), diastolic (cDBP), mean (cMAP), and pulse pressure (cPP) were entered individually into stepwise linear regression models to determine their association with E/Em or Em.

Results

In univariate analysis, cPP correlated most strongly with E/Em (Spearman’s rho=0.45, p<0.001), while cSBP correlated most strongly with Em (Spearman’s rho=−0.51, p<0.001). Multivariate analysis demonstrated that the pulsatile component of afterload, cPP, contributed most to E/Em (partial r2=23%); meanwhile the nonpulsatile components (cDBP and cMAP), were significant but small contributors (partial r2 of 6% and 5% respectively) of LV relaxation (Em).

Conclusion

The nonpulsatile components of aortic afterload (central mean aortic pressure (cMAP) and central aortic diastolic blood pressure cDBP), exhibited a weak but significant association with LV relaxation, while the pulsatile component of afterload, central aortic pulse pressure (cPP), exhibited strong association with LV filling pressure.

Background

In the general population, peripheral metabolic complications (MC) increase the risk for left ventricular dysfunction. Human immunodeficiency virus infection (HIV) and combination anti-retroviral therapy (cART) are associated with MC, left ventricular dysfunction, and a higher incidence of cardiovascular events than the general population. We examined whether myocardial nutrient metabolism and left ventricular dysfunction are related to one another and worse in HIV infected men treated with cART vs. HIV-negative men with or without MC.

Methods

Prospective, cross-sectional study of myocardial glucose and fatty acid metabolism and left ventricular function in HIV+ and HIV-negative men with and without MC. Myocardial glucose utilization (GLUT), and fatty acid oxidation and utilization rates were quantified using 11C-glucose and 11C-palmitate and myocardial positron emission tomography (PET) imaging in four groups of men: 23 HIV+ men with MC+ (HIV+/MC+, 42 ± 6 yrs), 15 HIV+ men without MC (HIV+/MC-, 41 ± 6 yrs), 9 HIV-negative men with MC (HIV-/MC+, 33 ± 5 yrs), and 22 HIV-negative men without MC (HIV-/MC-, 25 ± 6 yrs). Left ventricular function parameters were quantified using echocardiography.

Results

Myocardial glucose utilization was similar among groups, however when normalized to fasting plasma insulin concentration (GLUT/INS) was lower (p < 0.01) in men with metabolic complications (HIV+: 9.2 ± 6.2 vs. HIV-: 10.4 ± 8.1 nmol/g/min/μU/mL) than men without metabolic complications (HIV+: 45.0 ± 33.3 vs. HIV-: 60.3 ± 53.0 nmol/g/min/μU/mL). Lower GLUT/INS was associated with lower myocardial relaxation velocity during early diastole (r = 0.39, p < 0.001).

Conclusion

Men with metabolic complications, irrespective of HIV infection, had lower basal myocardial glucose utilization rates per unit insulin that were related to left ventricular diastolic impairments, indicating that well-controlled HIV infection is not an independent risk factor for blunted myocardial glucose utilization per unit of insulin.

Trial Registration

NIH Clinical Trials NCT00656851

Objectives

The objective of this prospective, single-site, two-year dietary intervention study was to evaluate the effects of moderate weight reduction and subsequent partial weight regain on cardiovascular structure and function.

Background

Obesity is associated with adverse cardiac and vascular structural and functional alterations.

Methods

Sixty obese subjects (age: 46±10 years, body mass index: 37±3 kg/m2) were evaluated during their participation in a weight loss study. Cardiac and vascular ultrasound studies were performed at baseline and at 3, 6, 12, and 24 months after start of intervention.

Results

Forty-seven subjects (78%) completed the entire two-year follow-up. Average weight loss was 7.3±4.0, 9.2±5.6, 7.8±6.6 and 3.8±7.9% at 3, 6, 12, and 24 months, respectively. Age- and sex- adjusted mixed linear models revealed that the follow-up time was significantly associated with decreases in weight (p<0.0001), left ventricular (LV) mass (p=0.001), and carotid intima-media thickness (p<0.0001); there was also significant improvement in LV diastolic (E’, p≤0.0001) and systolic (S’, p=.001) function. Partial weight regain diminished the maximal observed beneficial effects of weight loss, however cardiovascular parameters measured at two years still showed a net benefit compared with baseline.

Conclusions

Diet-induced moderate weight loss in obese subjects is associated with beneficial changes in cardiovascular structure and function. Subsequent weight regain is associated with partial loss of these beneficial effects.

Vascular calcium deposition in end-stage renal disease occurs commonly, however its relationship to cardiovascular risk factors and fetuin-A levels in African-Americans is not known. Compliant African-American HD patients (n=17) agreed to undergo a 64-slice multidetector computed tomography for the assessment of coronary artery calcium score (CACS). The relationship between traditional cardiovascular risk factors (i.e., age, gender, dialysis vintage, history of diabetes, means of the previous 3 years of the weekly pre-dialysis blood pressure and hemoglobin, means of monthly values of calcium, phosphorus, alkaline phosphatase, uric acid and albumin, and means of quarterly measures of parathyroid hormone and lipids), and fetuin-A levels and CACS was explored by univariate analyses. Serum phosphorus levels over the previous 3 years were well controlled. The CACS range was 0-3,877 Agatston units (mean: 996; median :196). Among the tested variables, only fetuin-A was significantly and inversely associated with CACS (standardized β = -0.64 [95% confidence limits [CL]: -18.09, -3.62], p=0.006). There was no association between age and fetuin-A level (standardized β = -0.02 [95%CL: -0.10, 0.23]). In conclusion, African-American patients on long-term HD and with good phosphorus control exhibit a strong inverse correlation between fetuin-A levels and CACS which is independent of age.

Cardiac resynchronization therapy (CRT) is beneficial for a majority of patients with medically-refractory heart failure due to severe left ventricular (LV) systolic dysfunction and prolonged interventricular conduction to improve symptoms and LV performance. An optimally programmed atrioventricular delay (AVD) during CRT can be also important to maximize the response in left ventricular function. Several Doppler-echocardiographic methods have been reported to be useful for determination of the optimal AVD. This review will discuss the various Doppler-based approaches to program the AVD in patients that receive CRT.

Background and Objectives

Vascular calcification is a major contributor to morbidity and mortality in hemodialysis. The objective of this pilot study was to determine the feasibility, safety and efficacy of sodium thiosulfate (STS) in the progression of vascular calcification in hemodialysis patients.

Methods

Chronic hemodialysis patients underwent a battery of cardiovascular tests. Those with coronary artery calcium (Agatston scores >50) received intravenous STS after each dialysis for 5 months (n = 22) and the tests were repeated. Changes in MDCT-determined calcification were assessed as the mean annualized rate of change in 3 vascular beds (coronary, thoracic and carotid arteries) and in L1-L2 vertebral bone density.

Results

Although individual analyses showed coronary artery calcification progression in 14/22 subjects, there was no progression in the mean annualized rate of change of vascular calcification in the entire group. The L1-L2 vertebral bone density showed no changes. There were no correlations between rates of progression of vascular calcification and phosphorus, fetuin or C-reactive protein levels. Changes in coronary artery calcification scores correlated with those of the thoracic aorta.

Conclusion

STS treatment is feasible, appears safe and may decrease the rate of progression of vascular calcification in hemodialysis patients. A large, randomized, controlled trial is warranted.