Sinisa Dimkovic

Relationship of reduced cerebral blood flow and heart failure severity in elderly males

Introduction. Brain detrimental effects are under-recognised complication of chronic heart failure (CHF). One of the major causes may be cerebral hypoperfusion. This study was designed to investigate the relationship between cerebral blood flow (CBF) and severity of CHF as well as to evaluate its determinants among different parameters of cardiac dysfunction. Methods. Seventy-one CHF males with NYHA class II and III and 20 control subjects age ≥ 55 years were recruited. CBF was evaluated by colour duplex sonography of extracranial arteries. Echocardiography, 6-min walk test, quality of life and endothelial function were also assessed. Serum NT-pro-BNP and adipokines levels (adiponectin and leptin) were measured. Results. CBF was significantly reduced in elderly patients with CHF compared to healthy controls (677 ± 170 vs 783 ± 128 ml/min, p = 0.011). Reduced CBF was associated with reduced left ventricular ejection fraction (LVEF) (r = 0.271, p = 0.022), lower 6-min walk distance (r = 0.339, p = 0.004), deteriorated quality of life (r = −0.327, p = 0.005), increased serum adiponectin (r = −0.359, p = 0.002), and NT-pro-BNP levels (r = −0.375, p = 0.001). In multivariate regression analysis, LVEF and adiponectin were independently associated with reduced CBF in CHF patients (R2 = 0.289). Conclusion. CBF was reduced in elderly males with mild-to-moderate CHF, and was associated with factors that represent the severity of CHF including high serum adiponectin and NT-pro-BNP levels, decreased LVEF, impaired physical performance, and deteriorated quality of life.

Risk Factors for Cardiovascular Calcifications in Non-Diabetic Caucasian Haemodialysis Patients

Background/Aims: Dialysis patients display an increased mortality which is associated with cardiovascular calcifications. Diabetes mellitus and ethnicity are known factors that affect the extent of cardiovascular calcifications. However, most studies have investigated mixed cohorts with diabetics and/or mixed ethnicity. Methods: Cardiovascular calcifications were assessed in non-diabetic Caucasian haemodialysis patients by the semiquantitative Adragao calcification score (X-ray pelvis and hands) and a novel composite calcification score encompassing the Adragao score as well as calcifications detected by X-ray of the fistula arm, echocardiography of heart valves and carotid ultrasound. Results: Using multivariate analysis, age, male gender, dialysis vintage, lower Kt/V, calcium-phosphate product, smoking and high-sensitivity CRP were independent risk factors for cardiovascular calcifications as assessed by the Adragao or the composite score. Pulse wave velocity was independently related to both calcification scores. Body mass index, cholesterol, triglycerides, iPTH and serum levels of fetuin-A and uncarboxylated matrix Gla protein were not associated with cardiovascular calcifications. Conclusions: In our cohort of non-diabetic Caucasian haemodialysis patients, age, male gender, dialysis vintage, smoking, calcium-phosphate product, high-sensitivity CRP and lower Kt/V were independent risk factors for cardiovascular calcifications. Whether lowering the calcium-phosphate product and increasing dialysis efficiency can reduce cardiovascular calcifications in dialysis patients remains to be determined.

Association of adiponectin with peripheral muscle status in elderly patients with heart failure

BACKGROUND Reduced peripheral muscle mass was demonstrated in patients with chronic heart failure (HF). Adipokines may have potent metabolic effects on skeletal muscle. The associations between adipokines, peripheral muscle mass, and muscle function have been poorly investigated in patients with HF. METHODS We measured markers of fat and bone metabolism (adiponectin, leptin, 25-hydroxy vitamin D, parathyroid hormone, osteoprotegerin, RANKL), N-terminal pro B-type natriuretic peptide (NT-pro-BNP) in 73 non-cachectic, non-diabetic, male patients with chronic HF (age: 68 ± 7 years, New York Heart Association class II/III: 76/26%, left ventricular ejection fraction 29 ± 8%) and 20 healthy controls of similar age. Lean mass as a measure of skeletal muscle mass was measured by dual energy X-ray absorptiometry (DEXA), while muscle strength was assessed by hand grip strength measured by Jamar dynamometer. RESULTS Serum levels of adiponectin, parathyroid hormone, osteoprotegerin, RANKL, and NT-pro-BNP were elevated in patients with chronic HF compared to healthy controls (all p<0.0001), while no difference in serum levels of leptin, testosterone or SHBG was noted. Levels of 25-hydroxy vitamin D were reduced (p=0.002) in HF group. Peripheral lean mass and hand grip strength were reduced in patients with HF compared to healthy subjects (p=0.006 and p<0.0001, respectively). Using backward selection multivariable regression, serum levels of increased adiponectin remained significantly associated with reduced arm lean mass and muscle strength. CONCLUSIONS Our findings may indicate a cross-sectional metabolic association of increased serum adiponectin with reduced peripheral muscle mass and muscle strength in non-cachectic, non-diabetic, elderly HF patients.

Relationship Between High Circulating Adiponectin With Bone Mineral Density and Bone Metabolism in Elderly Males With Chronic Heart Failure

BACKGROUND The aim of the study was to investigate the associations of adiponectin and leptin to bone mass and bone specific surrogates in elderly males with chronic heart failure (CHF). METHODS AND RESULTS Seventy-three males (mean age 68 +/- 7 years) with stable mild to moderate CHF and 20 healthy individuals age- and body mass index-matching underwent dual energy x-ray absorptiometry measurements (bone mineral density (BMD) at hip and lumbar spine, total bone mineral content, and body composition); echocardiography; 6-minute walk test; grip strength; and biochemical assessment including adiponectin, leptin, bone specific surrogates (osteocalcin, beta-CrossLaps, osteoprotegerin [OPG], receptor activator of nuclear factor kappaB ligand [RANKL]), parathyroid hormone, 25-hydroxy vitamin D, testosterone, sex hormone-binding globulin, and NT-pro-BNP. Serum adiponectin, osteocalcin, beta-CrossLaps, OPG, RANKL, and parathyroid hormone were significantly increased in CHF patients, whereas 25-hydroxy vitamin D was significantly lower compared to healthy controls. The significant positive association was found between adiponectin level with osteocalcin, beta-CrossLaps, OPG, and RANKL among CHF patients. In multivariate regression analysis, adiponectin was a significant determinant of total hip BMD, although the variance was small (r(2) = 0.239), whereas leptin was determinant for total bone mineral content (r(2) = 0.469) in patients with CHF. CONCLUSIONS Serum adiponectin is an independent predictor of BMD in elderly males with mild to moderate CHF, and showed a positive correlation to bone specific surrogates. Adiponectin, as cardioprotective hormone, seems to be able to exert a negative effect on bone mass in chronic heart failure. Further research is needed to confirm the potential for adipokines in the crosstalk between bone and energy metabolism in CHF patients.

Effect of beta blockade on natriuretic peptides and copeptin in elderly patients with heart failure and preserved or reduced ejection fraction: Results from the CIBIS-ELD trial☆ , ☆☆

BACKGROUND We sought to investigate the effect of beta-blocker (BB) up-titration on serum levels of NT-proBNP and copeptin in patients with heart failure (HF) with reduced (HFREF) or preserved ejection fraction (HFPEF). METHODS Serial measurements of NT-proBNP and copeptin were obtained after initiation of BB up-titration in 219 elderly patients with HFREF or HFPEF. RESULTS After initial increasing trend of NT-proBNP at 6 weeks in HFREF patients, there was a subsequent decrease at 12 weeks of BB treatment up-titration (p=0.003), while no difference was found compared to baseline levels. In contrast to NT-proBNP, there was a continuous decreasing trend of copeptin in HFREF patients (at 12 weeks: p=0.026). In HFPEF patients, NT-proBNP significantly decreased (p=0.043) compared to copeptin after 12 weeks of BB up-titration. CONCLUSIONS After 12 weeks of BB optimization copeptin might reflect successful up-titration faster than NT-proBNP in HFREF, while the opposite was found in patients with HFPEF.

Polymorphism of angiotensin converting enzyme in hemodialysis patients--association with cardiovascular morbidity.

INTRODUCTION Cardiovascular morbidity and mortality are the major concern in dialysis patients and many risk factors are thought to be involved in its pathogenesis. Apart from traditional and non-traditional risk factors, the genetic susceptibility may be of importance, including renin-angiotensin system gene polymorphism. The aim of this study was to analyse renin-angiotensin system polymorphism in our group of hemodialysis patients and to correlate the findings with cardiovascular morbidity. MATERIAL AND METHODS The study included 196 patients on regular hemodialysis on polysulphone membrane three times per week for more than six months. Genetic analysis was performed by using polymerase chain reaction-restriction fragment length polymorphism method. RESULTS Out of 196 patients, 55% had I/D genotype, 35% had D/D and 10% had I/I, including angiotensin-converting enzyme polymorphism. It was shown that the patients with D allele genotype developed a significantly higher incidence of left ventricular hypertrophy and peripheral vascular disease. The angiotensin-converting enzyme polymorphism showed a significant association with the incidence of cerebrovascular accident and hyperlipoproteinemia in our group of hemodialysis patients. CONCLUSION The angiotensin-converting enzyme gene polymorphism is associated with the development of cerebrovascular accidents and hyperlipoproteinemia. Allele D of this gene increases the risk for the development of left ventricular hypertrophy and peripheral vascular disease significantly in hemodialysis patients. A longer follow-up is needed to make the definitive conclusion about the influence of angiotensin-converting enzyme polymorphism on cardiovascular morbidity and its importance in everyday clinical practice.

Renoprotective effect of calcium channel blockers

The advancing chronic renal failure is at most the consequence of secondary haemodynamic and metabolic factors as intraglomerular hypertension and glomerular hypertrophy. Although tight blood pressure control is the major preventive mechanism for progressive renal failure, ACE inhibitors and angiotensin receptor blockers have some other renoprotective mechanisms beyond the blood pressure control. That is why these two groups of antihypertensive drugs traditionally have advantages in treating renal patients especially those with proteinuria over 400-1000 mg/day. Even if earlier experimental studies have shown renoprotective effect of calcium channel blockers, later clinical studies did not prove that calcium channel blockers have any advantages in renal protection over ACE inhibitors given as monotherapy or in combination with ACE inhibitors. It was explained by action of calcium channel blockers on afferent but not on efferent glomerular arterioles; a well known mechanism that leads to intraglomerular hypertension. New generations of dihydropiridine calcium channel blockers can dilate even efferent arterioles not causing unfavorable haemodynamic disturbances. This finding was confirmed in clinical studies which showed that renoprotection established by calcium channel blockers was not inferior to that of ACE inhibitors and that calcium channel blockers and ACE inhibitors have additive effect on renoprotection. Newer generation of dihydropiridine calcium channel blockers seem to offer more therapeutic possibilities in renoprotection by their dual action on afferent and efferent glomerular arterioles and, possibly by other effects beyond the blood pressure control.