Aortic stiffness, left ventricle hypertrophy, and homogeneity of ventricle repolarization in adult dialyzed patients

The reverse remodeling of the aorta in patients after renal transplantation - the value of aortic stiffness index: prospective echocardiographic study

BACKGROUND

Atherosclerosis is regarded as a combination of two major separate diseases: atherosis and sclerosis. Sclerotic component depends on deterioration of elastic properties of the aortic wall and is called aortic stiffness. The most valuable, non-invasive method of aortic stiffness assessment is echocardiography, which allows to calculate the aortic stiffness index (ASI). ASI is an independent predictor of all-cause and cardiovascular mortality in different groups of patients. The main aim of study was the assessment of the aortic reverse remodeling in patients with end-stage renal disease (ESRD) after renal transplantation (RT).

METHODS

Study group involved 42 patients aged 43.3 ± 12.6 years, including 19 women aged 49.9 ± 10.9 years and 23 men aged 41.5 ± 12.91 years, who have undergone RT from non-related renal transplant donors, The study protocol has been consisted of 5 stages: 1 week after RT, 3 months after RT, 6 months after RT, 1 year after RT and 3 years after RT. The echocardiographic examination was performed and measurements of Ao_max, Ao_min were done. On the base of obtained parameters ASI, aortic distensibility (AD) and aortic strain (AS) were calculated according to adequate formulas.

RESULTS

The improvement of indices characterizing the elastic properties of aorta were noted. These changes attained the statistically significant level only at the end of the observation. ASI just after RT was equal - 4.65 ± 1.58, three months after RT - 4.54 ± 1.49, six months after RT - 4.59 ± 1.61, one year after RT - 4.35 ± 1.21 and three years after RT - 3.35 ± 1.29, while AD reached respectively - 6.55 ± 3.76 cm²/dyn^-110^-6 just after RT, - 6.38 ± 3.42 cm²/dyn^-110^-6 three months after RT, - 6.53 ± 3.60 cm²/dyn^-110^-6 six months after RT, - 6.48 ± 2.79 cm²/dyn^-110^-6 one year after RT and - 8.03 ± 3.95 cm²/dyn^-110^-6 three years after RT. Noted AS values were equal - 6.61 ± 4.05%, just after RT, - 6.40 ± 3.58% three months after RT, - 6.56 ± 3.76%, six months after RT, - 6.45 ± 2.80% one year after RT, - 8.01 ± 3.97%. and three years after RT. The exact analysis of parameters concerning aortic function showed that to achieve ASI, AD and AS improvement, long time was needed, because the most significant changes of these indices were observed only between 1 year and 3 years after RT.

CONCLUSIONS

There is a relationship between renal transplantation and improvement of the aortic elastic properties. The recovery of the renal function allows to initiate the reparative processes leading to at least partial restitution of the structure and features of the aorta, which is called reverse remodelling. Improvement of aortic wall elastic properties after renal transplantation is a continuous and prolonged process.

A prospective observational study comparing a non-operator dependent automatic PWV analyser to pulse pressure, in assessing arterial stiffness in hemodialysis

Background

Chronic kidney disease (CKD) accelerates vascular stiffening related to age. Arterial stiffness may be evaluated measuring the carotid-femoral pulse wave velocity (PWV) or more simply, as recommended by KDOQI, monitoring pulse pressure (PP). Both correlate to survival and incidence of cardiovascular disease. PWV can also be estimated on the brachial artery using a Mobil-O-Graph; a non-operator dependent automatic device. The aim was to analyse whether, in a dialysis population, PWV obtained by Mobil-O-Graph (MogPWV) is more sensitive for vascular aging than PP.

Methods

A cohort of 143 patients from 4 dialysis units has been followed measuring MogPWV and PP every 3 to 6 months and compared to a control group with the same risk factors but an eGFR > 30 ml/min.

Results

MogPWV contrarily to PP did discriminate the dialysis population from the control group. The mean difference translated in age between the two populations was 8.4 years. The increase in MogPWV, as a function of age, was more rapid in the dialysis group. 13.3% of the dialysis patients but only 3.0% of the control group were outliers for MogPWV. The mortality rate (16 out of 143) was similar in outliers and inliers (7.4 and 8.0%/year). Stratifying patients according to MogPWV, a significant difference in survival was seen. A high parathormone (PTH) and to be dialysed for a hypertensive nephropathy were associated to a higher baseline MogPWV.

Conclusions

Assessing PWV on the brachial artery using a Mobil-O-Graph is a valid and simple alternative, which, in the dialysis population, is more sensitive for vascular aging than PP. As demonstrated in previous studies PWV correlates to mortality. Among specific CKD risk factors only PTH is associated with a higher baseline PWV.

Trial registration

ClinicalTrials.gov Identifier: NCT02327962.

Risk of sudden cardiac death in chronic kidney disease

The review discusses the epidemiology and the possible underlying mechanisms of sudden cardiac death (SCD) in chronic kidney disease (CKD), and highlights the unmet clinical need for noninvasive risk stratification strategies in these patients. Although renal dysfunction shares common risk factors and often coexists with atherosclerotic cardiovascular disease, the presence of renal impairment increases the risk of arrhythmic complications to an extent that cannot be explained by the severity of the atherosclerotic process. Renal impairment is an independent risk factor for SCD from the early stages of CKD; the risk increases as renal function declines and reaches very high levels in patients with end-stage renal disease on dialysis. Autonomic imbalance, uremic cardiomyopathy, and electrolyte disturbances likely play a role in increasing the arrhythmic risk and can be potential targets for treatment. Cardioverter defibrillator treatment could be offered as lifesaving treatment in selected patients, although selection strategies for this treatment mode are presently problematic in dialyzed patients. The review also examines the current experience with risk stratification tools in renal patients and suggests that noninvasive electrophysiological testing during dialysis may be of clinical value as it provides the necessary standardized environment for reproducible measurements for risk stratification purposes.