Cardioprotective effect of intradialytic exercise on left atrial mechanics.

Left atrial (LA) function plays a pivotal role in cardiac performance by modulating left ventricular (LV) function. Impairments in LV function are commonly reported during hemodialysis (HD), but available data describing changes in LA function are limited. There is growing evidence of the cardioprotective effect of intradialytic exercise (IDE) on LV function, but studies analyzing its effect on LA function are scarce. Our aim was to evaluate whether IDE can limit the severity of HD-induced impairment in LA myocardial function. In this prospective, open-label, two-center randomized crossover trial, 56 stable individuals receiving HD participated in 2 HD sessions in random order: standard HD and a session incorporating 30 min of aerobic exercise. LA and LV global longitudinal strains (GLSs) were obtained before and at peak stress of HD (i.e., 30 min before the HD ending). IDE totally eradicated the decline in LA reservoir strain observed during HD (estimated difference: 3.1%, 95% confidence interval: 0.4/5.8, P = 0.02), whereas it did not affect the other components of LA mechanics. A similar result favoring IDE intervention was also demonstrated on GLS changes over the HD procedure (P < 0.001). Between-session differences of changes in GLS and LA reservoir strain were correlated (r = -0.32, P = 0.03). The cardioprotective effect of IDE disappeared in patients with LA enlargement (i.e., LA volume index >34 mL/m2). In conclusion, even a short duration of IDE at moderate intensity is effective in preventing HD-associated decline in LA reservoir function. Further research is needed to explore the long-term benefits of IDE on LA function.NEW & NOTEWORTHY A single bout of intradialytic exercise (IDE) at moderate intensity can prevent the hemodialysis-associated decline in left atrial (LA) function. This was partially explained by the relative preservation of left ventricular systolic function with IDE. Benefits of IDE on LA function were lost in patients with LA dilation. Further studies are needed to explore the mechanisms behind IDE-induced cardioprotection and evaluate the clinical impacts of the repetitive cardioprotective effects of IDE on LA function.

Cardioprotective Effect of Acute Intradialytic Exercise: A Comprehensive Speckle-Tracking Echocardiography Analysis.

SIGNIFICANCE STATEMENT: Hemodialysis (HD) can lead to acute left ventricular (LV) myocardial wall motion abnormalities (myocardial stunning) due to segmental hypoperfusion. Exercise during dialysis is associated with favorable effects on central hemodynamics and BP stability, factors considered in the etiology of HD-induced myocardial stunning. In a speckle-tracking echocardiography analysis, the authors explored effects of acute intradialytic exercise (IDE) on LV regional myocardial function in 60 patients undergoing HD. They found beneficial effects of IDE on LV longitudinal and circumferential function and on torsional mechanics, not accounted for by cardiac loading conditions or central hemodynamics. These findings support the implementation of IDE in people with ESKD, given that LV transient dysfunction imposed by repetitive HD may contribute to heart failure and increased risk of cardiac events in such patients. BACKGROUND: Hemodialysis (HD) induces left ventricular (LV) transient myocardial dysfunction. A complex interplay between linear deformations and torsional mechanics underlies LV myocardial performance. Although intradialytic exercise (IDE) induces favorable effects on central hemodynamics, its effect on myocardial mechanics has never been comprehensively documented. METHODS: To evaluate the effects of IDE on LV myocardial mechanics, assessed by speckle-tracking echocardiography, we conducted a prospective, open-label, two-center randomized crossover trial. We enrolled 60 individuals with ESKD receiving HD, who were assigned to participate in two sessions performed in a randomized order: standard HD and HD incorporating 30 minutes of aerobic exercise (HDEX). We measured global longitudinal strain (GLS) at baseline (T0), 90 minutes after HD onset (T1), and 30 minutes before ending HD (T2). At T0 and T2, we also measured circumferential strain and twist, calculated as the net difference between apical and basal rotations. Central hemodynamic data (BP, cardiac output) also were collected. RESULTS: The decline in GLS observed during the HD procedure was attenuated in the HDEX sessions (estimated difference, -1.16%; 95% confidence interval [95% CI], -0.31 to -2.02; P = 0.008). Compared with HD, HDEX also demonstrated greater improvements from T0 to T2 in twist, an important component of LV myocardial function (estimated difference, 2.48°; 95% CI, 0.30 to 4.65; P = 0.02). Differences in changes from T0 to T2 for cardiac loading and intradialytic hemodynamics did not account for the beneficial effects of IDE on LV myocardial mechanics kinetics. CONCLUSIONS: IDE applied acutely during HD improves regional myocardial mechanics and might warrant consideration in the therapeutic approach for patients on HD.

Feasibility and early effects of bed-cycling eccentric training: Potential clinical applications.

PURPOSE: This study aimed to evaluate feasibility and early effects of moderate intensity bed-cycling eccentric training on healthy individuals, and establish whether this training modality could be implemented into bedridden patients' routine care. METHODS: Longitudinal study with prepost exercise intervention measurements. The development of a bed-adapted eccentric ergometer allowed to conduct five training sessions during 3 weeks at increasing intensity on 11 healthy individuals. Force-speed relationship, maximal voluntary knee extension force and neural activation of subjects were evaluated before and after the programme. RESULTS: Five training sessions were sufficient to decrease the rate of perceived exertion whereas eccentric power output increased (+40%). After training, maximal voluntary isometric contraction force measured during knee extension had significantly improved in all subjects, with a mean increase of 17%. Maximal cycling power was also significantly higher (+7%) after the training programme. CONCLUSION: Taken together, these results show that moderate load eccentric bed cycling (i) was feasible and efficient, (ii) did not generate excessive individual perception of effort during exercise nor develop major muscular or joint pain after training and (iii) allowed early force and power gains in healthy subjects.

Does the interference phenomenon affect strength development during same-session combined rehabilitation program in hemodialysis patients?

INTRODUCTION: This study aimed to assess if an interference effect could blunt the neuromuscular gains induced by a same-session combined rehabilitation in hemodialysis (HD) patients. METHODS: Patients exercised twice a week, for 16 weeks, over their HD sessions. They were either always trained with resistance and endurance exercises (continuous training, "CONT") or alternatively with 1 week of resistance alternated with 1 week of endurance (discontinuous training, "DISC"). Adherence and workload were continuously recorded. Short Physical Performance Battery (SPPB) score, one-leg balance test, and handgrip and quadriceps strength were evaluated before and after training intervention. RESULTS: Adherence to both programs was high (>90%). SPPB score had significantly improved (CONT: +1.5 point, DISC: +1.2 pt, p < 0.001), like one-leg balance test (CONT: +3.7 s, DISC: +5.5 s, p < 0.05), handgrip strength of exercised (CONT: +5.5 kg, DISC: +5.6 kg, p < 0.001) and of nonexercised arm (CONT: +4.4 kg, DISC: +2.8 kg, p < 0.01) as well as maximal quadriceps strength (+22 N·m for dominant and +29 N·m for nondominant leg in both groups, p < 0.001) bearing no difference between the trainings. CONCLUSION: Same-session combined training does not induce an interference effect in HD patients and temporal separation of exercises does not optimize strength gains. These practical data may be relevant for clinicians and practitioners to alternate endurance and resistance exercises.

[Kidney diseases in dystrophic epidermolysis bullosa: case report]. / Atteintes rénales au cours de l'épidermolyse bulleuse dystrophique héréditaire: à propos d'un cas.

Dystrophic epidermolysis bullosa is a genetic skin disease of which the recessive subtype also named Hallopeau-Siemens is the most severe. It is due to lack of expression of type VII collagen which is essential for dermal anchoring. Severe obstructive uropathies of the urethral and bladder area may occur during the first years of life, in relation to local bullous activity. As in acquired bullous diseases, glomerular complications may occur in the dystrophic form during the second and third decade. They consist mostly in AA amylosis or mesangial immunoglobuline A glomerulonephritis, in relation to chronic inflammation and repeated cutaneous infections. End stage renal failure occurs in most cases. Only haemodialysis was used as suppletive treatment in four patients for a short period.

[Renin-secreting tumour: about a new diagnosed case during pregnancy]. / Tumeur à rénine. A propos d'un nouveau cas diagnostiqué au cours d'une grossesse.

A 29 year-old female patient developed severe arterial hypertension in the beginning of her second pregnancy. Investigations performed at 16 weeks of amenorrhea showed hypokaliemia in relation to severe hyperreninism: plasma active renin was 25 fold normal value, 94% as prorenin (prorenin representing 94% of total renin). Radiological investigations including ultrasonography and MRI disclosed an homogenous and avascular tumor in the right kidney. Its ablation confirmed renin tumor, and allowed recovery from HTA and continuation of pregnancy. This is the 75th reported case in the literature, enabling to make a new statement about diagnostic and therapeutic procedures, which are modified during pregnancy by contra-indication to X-rays and renin-angiotensin-aldosteron axis inhibitors.

Patient referral is influenced by dialysis centre structure in the Diamant Alpin Dialysis cohort study.

BACKGROUND: Late referral (LR) to the nephrologist of patients with progressing chronic kidney disease (CKD) has numerous deleterious effects and is observed in many countries. The contributing factors associated with LR are controversial and poorly defined. We hypothesized that these factors might be better identified by analysing patients starting dialysis in three distinct European countries within the same area. METHOD: The referral and progression of kidney failure patterns were analysed with demographic, clinical and biological data in 279 non-selected consecutive patients starting dialysis in eight centres of three adjacent regions in France, Italy and Switzerland. RESULTS: Early referral (>6 months before the start of dialysis) was seen in 200 patients (71.6%), intermediate referral (1-6 months) in 42 (15.1%) and LR (<1 month) in 37 (13.3%). However inter-centre variations were between 2 and 19% for LR and 6-50% for combined late and intermediate referral. There were no differences at the national levels, but LR was more frequent in the large city centres than in the private or regional structures, with 31 out of 169 (18.3%), two out of 55 (5.4%) and four out of 55 (7.3%), respectively, of their patients (P<0.01). By multivariate analysis, it appears that, besides the presence of an active cancer and the CKD progression rate, the centre structure and the referring physician (primary care physicians and nephrologists are less responsible for LR than other medical specialists) play a significant role in the practice of LR. CONCLUSIONS: Within a dialysis cohort spread over adjacent regions of three countries, LR has the same global distribution pattern, indicating that different health and social security systems do not play a major role in inducing or preventing this practice. The contributing factors for LR that were identified are the type of the referring physician and the structure of the dialysis unit. Both factors are potential targets for an educational and collaborative approach.

The Diamant Alpin Dialysis cohort study: clinico-biological characteristics and cardiovascular genetic risk profile of incident patients.

BACKGROUND: Clinical and therapeutic characteristics of chronic dialysis patients vary widely at national and/or regional levels. Their increased cardiovascular (CV) mortality is not explained by traditional cardiovascular disease (CVD) risk factors only. Therefore, this study aimed to investigate and compare the characteristics of patients starting dialysis in a homogeneous Alpin region and possibly to identify new biological parameters (phenotypes or genotypes), which eould be responsible for the increased CVD seen in end-stage renal disease (ESRD) patients. METHODS: A cohort of 279 non-selected consecutive patients entering a dialysis program was prospectively investigated in eight centers of three adjacent regions in France, Italy and Switzerland. In addition to the usual demographic, clinical and biological data, we analyzed at study entry the blood levels of homocysteine, lipoprotein(a) (Lp(a)) and antioxidized low density lipoprotein (LDL) antibodies, vitamin B12 status, Lp(a) and haptoglobin phenotypes, methylenetetrahydrofolate reductase (MTHFR), angiotensin-converting enzyme (ACE), allele epsilon E4 of apolipoprotein (ApoE4) and plasminogen activator inhibitor-1 (PAI-1) genetic polymorphism. RESULTS: At entry, 90.3% of patients were hypertensive, 30% had type 2 diabetes mellitus and 17.6% were current smokers; 42% of patients had already experienced at least one CV event: peripheral artery disease (26% of the cohort), coronary artery disease (22%) or ischemic cerebro-vascular disease (16%). Forty-two patients had had > or =2 CV events or documented atherosclerotic localizations. Anemia was not optimally treated: mean hemoglobin (Hb) was at 97.7 g/L and, while overall 62% of patients received erythropoietin (EPO) prior to dialysis, large national differences were observed. Compared to the reference population, ESRD patients exhibited increased homocysteinemia, Lp(a) levels and ApoE4 allele prevalence. Conversely, the distribution of Lp(a) phenotype, MTHFR TT, ACE DD and PAI-1 4G/4G was equivalent to that of the reference population. In addition, none of the analyzed phenotypical or genotypical parameters, except for the haptoglobin 2.2 phenotype, could be associated with the existence of a previous adverse CV event. CONCLUSIONS: (1) The clinical characteristics of the ESRD patients entering dialysis in our region were comparable to the currently observed dialysis populations in most European countries with the deleterious role of advancing age, diabetes, previous CVD, smoking and hypertension evident (2). Except for anemia therapy, there were no regional or national differences observed at dialysis start. (3) An analysis of the phenotypic and genotypic CV risk factors demonstrated differences with the reference population only for hyperhomocysteinemia, Lp(a) and ApoE4 allele prevalence, with no notable differences among the participating centers.