Short-term evolution of cardiac structure and function in patients on maintenance hemodialysis for end-stage renal disease: A quasi-experimental, non-randomized, evaluation echocardiography study in Cameroon, sub-Saharan Africa.

To the Editor,

Adequate hemodialysis has been shown to improve volume overload and uremia in the short term. The short-term modifications to cardiac structure and function with hemodialysis in chronic kidney disease have not been prospectively studied in our setting.

Between December 2016 and May 2017, we carried out a quasi-experimental, non-randomized evaluation study in 2 hemodialysis centers: the university teaching hospital and the general hospital in Yaoundé, Cameroon. We included consenting adults aged ≥18 years, with an indication of maintenance hemodialysis. We collected baseline echocardiographic data before initiating dialysis, and after 60 days of thrice-weekly sessions of maintenance hemodialysis. Measurements were collected with a SonoScape S8 echograph (SonoScape Medical Corp., Shenzhen, China) by the same cardiologist, blinded to the pre-dialysis measurements.

A total of 31 patients with end-stage renal disease were recruited for the study. At day 60, 20 participants completed the study, and 11 were excluded from the analysis.

Of the 20 patients, there were 16 (80%) men. Their mean age was 45±14 years (range: 22-70 years). The most frequent abnormalities were diastolic dysfunction in 19 (95%), with 5 grade 1 (26.3%), 7 grade 2 (36.8%), and 7 grade 3 (36.8%); left atrial (LA) dilation in 14 (70%); and left ventricular hypertrophy (LVH) in 12 (60%), with 10 concentric LVH and 2 eccentric LVH.

All systolic dysfunction (100%) was mild (ejection fraction: 40-50%).

After the 16th hemodialysis session, LV mass index decreased by 15% (p=0.01), and LA volume decreased by 40.1% (p=0.01).

The LV ejection fraction increased by 4.4% units overall (p=0.67). The overall E/Ea ratio decreased by 23.3% (p=0.07). The improvements in LV structure and function were significant in those with initially abnormal values.

The rate of echocardiographic abnormalities in this study was similar to that reported by other authors (1, 2). Ejection fraction is an insensitive marker of LV function compared with myocardial deformation-strain and strain rate (3). Covic et al. (4) also noted a marginal increase in LV ejection fraction after 22 months of follow-up in a cohort of 150 patients. LV diastolic dysfunction with elevated filling pressure (E/Ea ratio) improved significantly. Hampl et al. (5) reported a significant reduction in LV mass in 22% of patients after 18 months of follow-up. We have shown that the reduction in LV mass with twice-weekly hemodialysis occurs in as little as 2 months. LV hypertrophy can be a result of volume and or pressure overload. We noted a marked reduction of almost 50% in LA volume. This suggests that LA volume assessment is a sensitive marker of changes in LA size. Similar reductions were reported by Covic et al. (4). We did not find any determinant of improvement of LV structure and function.

In conclusion, The LV mass and LA size were significantly reduced with hemodialysis after the 16th session. LV diastolic function also significantly improved. We suggest further studies be carried out on a larger sample and include strain rate in assessing LV systolic function.