Pararenalfat Tissue: Rate of Pararenal Obesity and Relation with Anthropometric Indices of Obesity

Aim. To study a rate of excessive pararenal fat tissue (PRFT) thickness and its relationship with anthropometric obesity indices.Material and methods. 372 patients (152 men and 220 women) were included in the study, the average age was 63.5±13.3 years. There were measured: height, weight, waist circumference (WC), hip circumference (HC), body mass index (BMI), WC/height ratio, sagittal abdominal diameter (SAD), body fat percentage (BFP), body surface area (BSA), body adiposity index (BAI) and visceral obesity index (VAI). All subjects underwent abdominal multispiral computed tomography. PRFT thickness was detected on a single slice at the level of the left renal vein.Results. 27% of the examined group had BMI<25 kg/m2, 28% – excessive body mass, 45% – obesity. The median PRFT thickness was 1.61 (1.03; 2.46) cm. There were correlations between PRFT thickness and glucose (r=0,64, p<0,05) and uric acid (r=0,46, p<0,05) levels. The threshold of referential PRFT thickness was 1,91cm. The rate of pararenal obesity was 9,9% among those with normal body mass, 29,3% in excessive body mass, 66,1% – in 1 class obesity, 67,7% – in 2 class, and 90,1% – in 3 class. The correlation analysis revealed a significant positive correlation between the PRFT thickness and obesity indices with exception of VAI and BAI: with BMI (r=0.43, p<0.05), WC (r=0.57, p<0.05), SAD (r=0.58, p<0.05), BFP (r=0.48, p<0.05), WC/height ratio (r=0.46, p<0.05), and BSA (r=0.58, p<0.05).Conclusion. Excessive PRFT may be detected isolated without any external anthropometric signs of obesity, wherein it is an active component of metabolic disorders typical for obesity. The most significant indices for the detection of pararenal obesity may be WC, SAD, and BSA.

[Ectopic obesity in patients without manifested cardiovascular disease: regulations, frequency and clinical characteristics]

AIM

To determine the frequency, distribution and characteristics of ectopic obesity in patients without manifested cardiovascular disease.

MATERIALS AND METHODS

We examined 320 patients without manifested cardiovascular disease (average age 63.813.9 years), 38 of them without cardiovascular risk factors (healthy referent group). Anthropometric indicators were measured, body mass index (BMI) was calculated. Degree, type of obesity, lipid profile were evaluated. All patients underwent multi-detector chest computed tomography in spiral mode on Toshiba Aquilion Prime scanner using standardized protocol. Perivascular adipose tissue (PVAT) and pericardial adipose tissue (PAT) were detected using specialized semi-automatic software Tissue Composition Module QCTPro (Mindways Software, Inc., USA) after scanner calibration with special phantom. PAT and PVAT exceeding the 90th percentile in the healthy referent group were considered as ectopic obesity. Statistical analysis was performed using Statistica 10.0 software (StatSoft Inc., USA).

RESULTS

PAT volume 3.2 cm3 and PVAT volume 0.4 cm3 were criteria for high pericardial and high perivascular fat; 81 (25.2%) patients had ectopic obesity, 85 (26.5%) patients abdominal obesity; 146 (42.9%) people had high pericardial fat, 134 (39.4%) high perivascular fat. The frequency of ectopic obesity in patients with arterial hypertension (AH) was statistically significantly higher compared to persons without AH. Significantly more often ectopic forms of obesity were detected in patients with overweight and obesity. The high pericardial fat and high perivascular fat were found in patients with overweight and normal body weight. When comparing the clinical characteristics of patients with abdominal and ectopic obesity, metabolic parameters, as well as the incidence of hypertension and dyslipidemia, did not differ significantly.

CONCLUSION

Ectopic obesity can develop outside of global obesity. In addition, this type of obesity is accompanied by metabolic disorders and AH, regardless of the abdominal distribution of adipose tissue.

Relationship between the volume of perivascular adipose tissue and the vascular wall lesion

Aim. To study the relationship between the volume of perivascular adipose tissue (PVAT) and the vascular wall lesion.

Material and methods. The study included 318 patients without cardiovascular disease (mean age, 63,5±13,7 years). Hypertension was detected in 268 (84,3%) patients. All patients underwent assessment of anthropometric characteristics, lipid profile, arterial wall stiffness with the estimation of cardio-ankle vascular index, intima-media thickness, brachial artery endothelial vasomotor function. Chest computed tomography was performed with the estimation of the volumes of PVAT and pericardial adipose tissue (PAT).

Results. The volume of PVAT, on average, was 0,3 [0,2; 0,4] cm3 . The VAT volume was significantly higher in obese individuals when compared with patients with normal body weight: 0,4 [0,3; 0,5] vs 0,25 [0,2; 0,4] cm3 (p=0,0007). The VAT volume was higher in individuals with an increased CAVI level when compared with patients with normal CAVI values: 0,4 [0,3; 0,5] vs 0,3 [0,25; 0,3] (p=0,02). A significant correlation was found between the VAT volume and body mass index (r=0,27, p<0,005), waist circumference (r=0,41, p<0,005), CAVI (r=0,49, p<0,05), impaired endothelium-dependent brachial artery vasodilation (r=0,38, p<0,05). When performing multiple linear regression, a significant relationship of CAVI was found with age (β±SE, 0,51±0,15; p=0,002) and volume of PVAT (β±SE, 0,41±0,13; p=0,005).

Conclusion. The results indicate the relationship of PVAT with visceral obesity and vascular wall stiffness parameters.

Role of epicardial adipose tissue in the development of atrial fibrillation in hypertensive patients

Obesity is a progressing epidemic, the prevalence of which has doubled over the past 30 years. The distribution of adipose tissue is an important factor in predicting the risk of cardiovascular events. The most significant inflammatory activity is characteristic of epicardial adipose tissue (EAT), the role of which in the development of atrial fibrillation (AF) remains a subject of discussion.

Aim. To study the effect of EAT size on the development of AF in hypertensive (HTN) patients.

Material and methods. The study included 95 patients with HTN aged 38-72 years (mean age, 61,5±1,8 years), including 45 patients with paroxysmal AF (group I) and 50 patients in the comparison group (group II). In order to assess the severity of visceral obesity, all patients underwent a general examination and echocardiography. To determine the EAT volume, cardiac multislice computed tomography was performed.

Results. Echocardiography revealed that the EAT thickness was significantly greater in hypertensive patients with paroxysmal AF than in the comparison group: 11,6±0,8 and 8,6±0,4 mm, respectively (p<0,001). According to cardiac multislice computed tomography, a significant increase in EAT volume was revealed in patients of group I (4,6±0,4 ml) compared with group II (3,5±0,25 ml) (p=0,019). In hypertensive patients with paroxysmal AF, a positive moderate relationship between the EAT volume and left atrial volume was revealed (r=0,7, p=0,022). Multivariate analysis showed that in hypertensive patients, EAT thickness >10 mm and volume >6 ml can serve as integral markers of the onset of paroxysmal AF.

Conclusion. Integral markers of AF in hypertensive patients are an increase in the EAT thickness >10 mm (odds ratio, 4,1; 95% confidence interval, 1,1-5,6) and volume >6 ml (odds ratio 3,7; 95%, confidence interval 1,0-4,2).

Changes in Arterial Wall Stiffness in Patients with Obesity and Paroxysmal Form of Atrial Fibrillation

Aim. To study changes in vascular wall stiffness in patients with obesity and paroxysmal atrial fibrillation (AF) during sinus rhythm retention.

Material and methods. The study included 86 obese patients aged 38 to 72 years. Patients were divided into 2 groups: 42 patients with paroxysmal AF and obesity (Group I) and 44 patients with obesity and without rhythm disturbance (Group II). All patients were evaluated for the main parameters of arterial wall stiffness: the heart-ankle vascular index (CAVI) and the ankle-brachial index (ABI) in the right and left main arteries.

Results. Body mass index (BMI) did not differ significantly between groups. The prevalence of visceral obesity in patients with paroxysmal AF was significantly higher than in patients without heart rhythm disorders. The study of vascular wall rigidity revealed a significant increase in the CAVI index in patients with paroxysmal AF compared with this in patients without cardiac arrhythmia. The average value of the CAVI index was 9.61±1.51 and 7.92±0.18, respectively (p=0.0003). In patients with obesity and paroxysmal AF, correlations were found between waist circumference to hip circumference (WC/HC) ratio and CAVI index (r=0.455, p=0.004); WC/height ratio and CAVI index (r=0.443, p=0.003); between WC and CAVI index (r=0.493, p=0.002). A positive direct relationship was found between CAVI index and the frequency of AF attacks during the year: r=0.782 (p=0.001).

Conclusion. A significant increase in the CAVI index, indicating a change in vascular wall stiffness, was found in patients with obesity and paroxysmal AF when compared with overweight patients without heart rhythm disorders. The increase in the CAVI index was correlated with the increase in WC, the WC/HC ratio, and WC/height ratio. There was a significant direct relationship between the CAVI index and the frequency of arrhythmia attacks in patients with obesity and paroxysmal AF.

Resistant Hypertension: Questions and Contemporary Answers

The review presents the important problem of resistant hypertension. Its real prevalence is unknown. According to population studies and metaanalyzes of clinical studies, the prevalence of this most severe form of hypertension reaches 12-15% in the general population and 15-18% in clinical cohorts. Over the past decades, an increase in its frequency among patients with hypertension has been noted. Based on the results of large-scale studies, risk factors are detected that allow to assess the risk for the resistance to antihypertensive drugs. Adherence to ongoing antihypertensive therapy is crucial to addressing the issue of hypertension resistance; there are acceptable ways to evaluate it in clinical practice. The review discusses the most common mistakes in the choice of therapy, which can cause resistance to antihypertensive treatment, namely irrational drug combinations, insufficient dosage of the drug, and the use of non-prolonged forms of drugs. The latest recommendations for the diagnosis and treatment of hypertension, including its resistant form, are analyzed. The review contains a rationale based on the results of randomized clinical trials, the choice antihypertensive strategy in this variant of arterial hypertension. The importance of fixed combination antihypertensive drugs, as well as thiazine-like diuretics and amlodipine is stressed. The results of studies demonstrate the rational for the use of antimineralcorticoid drugs, namely spironolactone, for this category of patients. The authors offer an updated algorithm for the diagnosis and treatment of resistant hypertension, based on the sections of the latest clinical recommendations on this problem.

[A fixed-dose lisinopril+amlodipine+rosuvastatin combination: prospects for its use in patients with hypertension and concomitant dyslipidemia]

In Russia, target blood pressure (BP) levels are achieved in only 14.4% of men and in 30.9% of women. The need for combination therapy of hypertension is as high as 70.7%. There are well-known benefits of combined antihypertensive therapy allowing for higher efficiency and better tolerability. One of the current combinations is a combination of an angiotensin-converting enzyme inhibitor and a calcium antagonist, which have pronounced protective activity and metabolic neutrality. Fixed-dose combinations have substantial advantages over free ones, contributing to improving patient compliance with the used treatment regimen. Dyslipidemia is present in 60.7% of the hypertensive patients. Nonetheless, only 9.7% of Russian patients with coronary heart disease take statins and control of lipid levels remains very poor. The review discusses whether the use of the triple combination lisinopril + amlodipine + rosuvastatin is reasonable from the standpoint of evidence-based medicine. There are literature data suggesting the high value of this fixed-dose combination in the context of organ protection and the reduced risk of cardiovascular events.