Insulin resistance and coronary flow velocity reserve in patients with autosomal dominant polycystic kidney disease.

BACKGROUND: Cardiovascular problems are a major cause of morbidity and mortality in patients with autosomal dominant polycystic kidney disease (ADPKD). AIM: The aim of this study was to investigate coronary flow velocity reserve (CFVR) as a marker of endothelial dysfunction, carotid intima media thickness (CIMT) as a marker of subclinical organ damage and insulin resistance (IR) as a cardiovascular risk factor in patients with ADPKD. METHODS: Twenty-two normotensive ADPKD patients with well-preserved renal function and 19 healthy subjects were included in the study. Creatinine clearances were calculated by the Cockcroft-Gault formula. The homeostasis model of IR (HOMA-IR) was used to measure IR. CIMT was measured by high-resolution vascular ultrasound. CFVR was calculated as the ratio of hyperaemic to baseline diastolic peak velocities by echocardiography. RESULTS: There was no significant difference between the two groups regarding age, gender, body mass index, systolic and diastolic blood pressures, cholesterol and triglyceride levels. However, CIMT and HOMA-IR were significantly increased and CFVR was significantly decreased in patients with ADPKD compared with healthy subjects. CONCLUSIONS: The findings of decreased CFVR, increased CIMT and increased IR suggest that cardiovascular risk is elevated even in the early stages of ADPKD.

Isokinetic evaluation of ankle muscle strength and fatigue in patients with ankylosing spondylitis.

AIM: The aim of the study was to compare the strength and fatigue of ankle plantarflexor/dorsiflexor muscles using isokinetic dynamometer in patients with ankylosing spondylitis (AS) versus healthy control subjects. DESIGN: A controlled study. SETTING: Outpatients clinic of our Department of Physical Medicine and Rehabilitation. POPULATION: Twenty-six AS patients and 26 control subjects participated in this study. METHODS: In both groups the isokinetic tests are conducted by isokinetic dynamometer.The evaluations were made in plantarflexion/dorsiflexion patterns;peak torque, agonist/antagonist ratio and work fatigue isokinetic parameters were evaluated for the ankle 30 º/s, 60º/s, 120º/s angular velocities. Pain severity, clinical findings, and functional status were also evaluated in the study group. RESULTS: In the patient group, ankle plantarflexion muscle strength was significantly lower compared to the control group in all angular velocities (P<0.05). Agonist/antagonist ratio was significantly lower in the patient group compared to the control group in all angular velocities (P<0.01). The work fatigue was decreased for bilateral ankle plantarflexors at 120º/s angular velocities (P<0.05). There was no significant difference between the measurements of ankle dorsiflexors (P>0.05). There was no relation between the decreased muscle strength and pain severity, clinical findings, and functional status of AS patients. CONCLUSION: We found ankle muscles fatigue and decreased ankle plantarflexor muscle strength in patients with AS compared to control subjects.

Left atrial geometric and functional remodeling in athletes.

The aim of this study was to evaluate left atrial (LA) volume and its changes with the phases of atrial filling, and to examine the effect of exercise capacity on these parameters. Using two-dimensional echocardiography, LA volumes were measured in 30 male endurance runners and 30 age-matched sedentary men (controls). Maximal oxygen consumption (VO2max) was measured using a metabolic chart during exercise. LA reservoir, pump, and conduit functions, kinetic energy and force were calculated. We found that athletes had higher LA volume and volume index (except the conduit volume), LA passive emptying fraction, and LA total emptying fraction compared to control subjects. We observed positive correlations between: VO2max and LA passive emptying fraction (r=0.49, p<0.05); VO2max and LA active emptying fraction (r=0.54, p<0.05); VO2max and LA kinetic energy (r=0.61, p<0.05); and VO2max and LA force (r=0.57, p<0.05). These findings suggest that atrial function reflects exercise capacity in athletes.

Effects of levosimendan on left ventricular functional remodelling and exercise intolerance: a tissue Doppler study.

Levosimendan is a calcium sensitizer that demonstrates enhanced myocardial contractility. There is little information concerning the effect of levosimendan on left ventricular tissue parameters and exercise capacity. We evaluated the effects of a 24-h course of levosimendan therapy on cardiac tissue parameters in 30 patients, aged 48 - 70 years, admitted to our hospital for the management of decompensated heart failure. All patients underwent echocardiographic examination using tissue Doppler imaging (TDI) and a 6-min walk test. Systolic myocardial velocity of the mitral annulus (Sm) was significantly increased in levosimendan-treated patients compared with placebo-treated patients. There was a positive correlation between Sm and exercise capacity. Levosimendan might be expected to increase cardiac contractile force, especially Sm velocity, in parallel with exercise tolerance. The study has also shown that the progress of ventricular function after levosimendan treatment in patients with exercise intolerance could be monitored effectively by Sm velocity measurements using TDI.

Aortic distensibility and left ventricular diastolic functions in endurance athletes.

Aortic elastic properties are important determinants of left ventricular function. The aim of this study was to determine left ventricular diastolic function and aortic distensibility in endurance athletes. Thirty male runners and thirty age-matched healthy male controls took part in the study. All subjects underwent echocardiographic examination and cardiopulmonary exercise testing. Measurements included LV cavity dimension, standard and tissue Doppler parameters, and aortic diameter, 3 cm above aortic valve, at systole and diastole. Maximal oxygen uptake in athletes was higher than in controls. The aortic distensibility index was found to be higher in athletes compared with controls (5.37 +/- 1.50 vs. 3.37 +/- 1.48 cm (2) . dynes (-1) . 10 (-6), p < 0.001). While the aortic stiffness index in athletes was significantly lower than in controls (2.77 +/- 0.28 vs. 3.43 +/- 0.41, p < 0.001). Furthermore, transmitral early peak velocity (E) and late peak velocity (A), peak velocity of myocardial systolic wave (S (m)), early (E (m)) and atrial (A (m)) diastolic waves in athletes were higher than in controls. It seemed that the association of E (m) velocity with aortic distensibility was stronger than that of other LV parameters (coefficient = 0.74, p < 0.001) by using multiple linear regression. Increased aortic distensibility in endurance-trained athletes may cause better diastolic function as a physiological cardiovascular adaptation factor.

Does the endothelial function change in renal transplant patients with longer duration of exposure and with higher cumulative doses of cyclosporine?

OBJECTIVE: Administration of cyclosporine (CsA) is one potential cause of endothelial dysfunction in renal transplant patients. We sought to investigate endothelial functional changes with respect to the cumulative dose and duration of exposure to CsA. METHODS: Sixty-six renal recipients and 25 healthy controls were included in the study. The recipients were classified according to their time of CsA exposure: group 1 (0 to 36 months); group 2 (36 to 72 months); and group 3 (over 72 months). Endothelial function of the brachial artery was evaluated using high-resolution vascular ultrasound. Endothelium-dependent and -independent vasodilatation (EDD and EID, respectively) were assessed by assessing the responses to reactive hyperemia and using sublingual isosorbide dinitrate (ISDN), respectively. RESULTS: There were no statistically significant differences between the groups with regard to their demographic, clinical, and most biochemical characteristics. Baseline measurements of the diameter of the brachial artery were similar in all groups. The values of mean brachial artery EDD and EID responses in groups 1, 2, and 3 were less than those in the control group (P < .05, P < .05, and P < .05, respectively). Mean brachial artery EDD and EID in group 1 were significantly impaired compared to groups 2 and 3 (for EDD: P < .05 and P < .05, respectively; for EID: P < .05 and P < .05, respectively). In contrast there was no difference between groups 2 and 3 with respect to these parameters. There were mild to moderate positive correlations between the cumulative doses of CsA and EDD and EID (r = .26 and r = .52, P < .05, respectively). CONCLUSION: Endothelial dysfunction was more prominent in the first 36-month period than later despite the longer exposure to and higher cumulative doses of CsA. This finding may reflect an extended effect of the uremic state on endothelial function or more intense doses of CsA in early posttransplant period.

Is there a relation between duration of cyclosporine usage and right and left ventricular function in renal transplant patients? Tissue Doppler Echocardiography study.

BACKGROUND: Our aim was to investigate the effect of cyclosporine (CsA), which is commonly used in renal transplant patients and causes myocardial fibrosis and elevated arterial tension, on cardiac function. METHODS: Sixty-six renal transplant patients (RTPs) and 25 healthy controls were included in the study. Renal transplantation patients were divided according to time of CsA exposure: group 1 (0 to 36 months); group 2 (36 to 72 months) and group 3 (> 72 months). Systolic peak velocity (Sm, mitral; St, tricuspid) and mitral early (e)/late (a) (Me/a) and tricuspid e/a (Te/a) waves of the right and the left ventricles were measured by pulse-wave (PW) Doppler used for tissue Doppler imaging of both ventricles as well as the ventricle free wall near to the lateral tricuspid and the posterior mitral leaflets. The measurements included conventional diastolic early (E) and late (A) waves and deceleration time (DT) of the E wave, isovolumetric relaxation time (IVRT) of both ventricles, as well as left ventricular systolic ejection fraction (EF). RESULTS: There were no statistically significant differences between the groups with regard to demographic, clinical, and most biochemical characteristics. Left ventricular EF was normal in all groups; there were no statistically significant differences. IVRT and DT of left ventricle and right ventricle DT values were similar among RTPs. On the other hand, values were found to be increased in RTP groups compared with the control group. E/A ratio, Me/a Te/a of both ventricles were similar among RTPs. However, these values were found to be decreased in RTP groups compared with the control group. CONCLUSIONS: Although left ventricular systolic functions were normal in all groups, there were statistically significant impairments of biventricular diastolic function parameters among renal transplant recipients compared with the control group.

Qt dispersion in soccer players during exercise testing.

Screening for cardiac health should involve relevant parameters or indices that are easy and inexpensive to obtain. Various cardiac adaptation mechanisms develop during regular exercise that are affected by many factors, and these are reflected on a surface electrocardiogram. QT dispersion has been considered a surrogate for heterogeneity of repolarization, leading to ventricular arrhythmias. We compared QT parameters between athletes and sedentary subjects. A total of 225 men were assessed, comprising a group of professional soccer players and sedentaries. Each subject underwent supine 12-lead electrocardiographic examinations and exercise testing by ergospirometry. QT parameters were taken at rest and at peak exercise. Peak oxygen consumption was considerably higher in the athletes than in the controls (59.3 +/- 5.6 vs. 44.3 +/- 2.4 ml/kg/min, mean +/- SD, p < 0.001). QT parameters at rest: There were significant differences in heart-rate-corrected rest maximal QT duration (413.9 +/- 50.5 vs. 445.3 +/- 45.7 ms, p < 0.001) and in heart-rate-corrected rest minimum QT duration (380.5 +/- 51.2 vs. 409.5 +/- 46.7 ms, p < 0.001). QT parameters at peak exercise: maximal QT duration at peak exercise (253.9 +/- 20.8 vs. 261.7 +/- 26.2, p = 0.02), QT dispersion at peak exercise (25.2 +/- 9.1 vs. 29.5 +/- 15.8 ms, p = 0.04), heart-rate-corrected QT dispersion at peak exercise (44.6 +/- 16.4 vs. 52.6 +/- 28.3 ms, p = 0.03) differed significantly between professional soccer players and controls. QT dispersion and corrected QT dispersion at peak exercise are lower in athletes than in controls. Athletes and other subjects identified with a long QT interval should be examined at regular intervals.