Changes in right ventricular dimensions, function, and pulmonary circulation loading according to the degree of interdialytic weight gain in maintenance hemodialysis patients

INTRODUCTION

The aim of this study was to investigate changes in echocardiographic right ventricular (RV) indices in relation to the degree of fluid accumulation between hemodialysis sessions, evaluated according to the recommended threshold of interdialytic-weight-gain corrected for dry weight (IDWG%).

METHODS

A post-hoc analysis was performed using data from 41 maintenance hemodialysis patients. Patients were divided into a higher (>4.5%) and a lower (<4.5%) IDWG% group and underwent an echocardiographic assessment at the start and the end of the 3-day and the 2-day interdialytic interval.

RESULTS

RV systolic pressure (RVSP) increments were more pronounced in the higher compared to the lower IDWG% group (16.43 ± 5.37 vs. 14.11 ± 13.38 mm Hg respectively, p = 0.015) over the 3-day interval, while changes in RV filling pressures, did not differ significantly between the groups (p = 0.84).

CONCLUSIONS

During the 3-day interdialytic interval, pulmonary circulation is particularly overloaded in patients with fluid accumulation higher than the recommended thresholds, as evidenced by higher RVSP elevations.

Haemodialysis acutely deteriorates left and right diastolic function and myocardial performance: an effect related to high ultrafiltration volumes?

Background

The effect of acute preload reduction during haemodialysis on left ventricle (LV) and right ventricle (RV) function is not well understood. This study aimed to evaluate acute changes in novel echocardiographic and tissue Doppler-derived indices of LV and RV function during the first and a standard weekly dialysis session and to examine the possible effect of acute intradialytic volume changes in LV and RV diastolic function and pulmonary circulation loading.

Methods

Forty-one adult patients receiving standard thrice-weekly haemodialysis participated in this study. Two-dimensional echocardiographic and tissue Doppler imaging (TDI) studies were performed with a standard cardiac ultrasound device (Vivid 7 or Vivid e, GE, Horton, Norway) shortly before and after the first weekly and a standard dialysis session. Multiple linear regression analysis was applied to assess the effect of volume changes on peak early mitral (E) and tricuspid (E RV) velocities changes.

Results

Significant reductions from pre- to post-haemodialysis were noted in body weight and systolic blood pressure. Post-haemodialysis left and right atrial, LV and RV sizing echocardiographic parameters were lower. LV systolic function, represented by LV ejection fraction, cardiac output and mean peak systolic LV and RV velocities at the annulus level, was unchanged. Diastolic function indices such as E (first session: 0.96 ± 0.28 versus 0.75 ± 0.27 m/s, P < 0.001; standard session: 0.89 ± 0.24 versus 0.78 ± 0.29, P < 0.001) and E RV (first session: 0.89 ± 0.26 versus 0.67 ± 0.25 m/s, P < 0.001; standard session: 0.86 ± 0.24 versus 0.77 ± 0.31, P < 0.001), E/A LV ratio, TDI peak early mitral (E') velocity and E'/A' RV ratio were reduced after haemodialysis. Pulmonary circulation loading, represented by RV systolic pressure, was significantly improved. In multiple regression model analysis, intradialytic weight loss was independently associated with changes in E [β = 0.042 (95% CI 0.018-0.066)] and E RV [β = 0.084 (95% CI 0.057-0.110)].

Conclusions

This study shows that haemodialysis deteriorates cardiac diastolic function indices and improves pulmonary circulation loading, while systolic function remains unchanged. High intradialytic volume removal may affect cardiac diastolic function.

Echocardiographic Parameters During Long and Short Interdialytic Intervals in Hemodialysis Patients

BACKGROUND

The long interdialytic interval in thrice-weekly hemodialysis is associated with excess cardiovascular risk. However, the mechanisms behind these adverse consequences are not fully understood. This study investigated the interdialytic changes in right and left ventricular function during the 2- and 3-day intervals.

STUDY DESIGN

Observational study with 2 random crossover sequences of recordings: 3-day followed by 2-day interval or vice versa.

SETTINGS & PARTICIPANTS

41 stable patients with end-stage renal disease on standard thrice-weekly hemodialysis therapy.

PREDICTOR

3-day (long) versus 2-day (short) interdialytic interval.

OUTCOME

Interdialytic change in echocardiographic indexes of left and right ventricular function.

MEASUREMENTS

2-dimensional echocardiographic and tissue Doppler imaging studies were performed with a Vivid 7 cardiac ultrasound system at the start and end of the 3- and 2-day interdialytic intervals.

RESULTS

During both intervals studied, elevations in cardiac output, stroke volume, left ventricular mass index, and peak early diastolic velocities of the left ventricle were evident. Interdialytic weight gain (3.0±1.7 vs 2.4±1.3 [SD] kg) and inferior vena cava diameter increase (0.54±0.3 vs 0.25±0.3) were higher during the 3-day versus the 2-day interval (P<0.001). Left ventricular systolic and diastolic function indexes were generally no different between interdialytic intervals. In contrast, interdialytic increases in left and right atrial volume, right ventricular systolic pressure (RVSP; 15.3±10.2 vs 4.7±5.2mmHg; P<0.001), and tricuspid regurgitation maximum velocity (0.46±0.45 vs 0.14±0.33m/s; P=0.001) were significantly greater during the 3- versus the 2-day interval. Multivariable analysis suggested that changes in interdialytic weight gain, right ventricle diastolic function, and pulmonary vascular resistance were determinants of the change in RVSP.

LIMITATIONS

Observational study design.

CONCLUSIONS

Excess volume accumulation over the long interdialytic interval in hemodialysis patients results in higher left and right atrial enlargement and RVSP elevation, which clinically corresponds to pulmonary circulation overload, providing one plausible pathway for the excess mortality risk during this period.

Quinidine: an "endangered species" drug appropriate for management of electrical storm in brugada syndrome

Brugada syndrome is an inherited channelopathy associated with an increased risk of syncope and sudden cardiac death. In rare cases it can be manifested with electrical storm. We report two cases of Brugada syndrome that presented with electrical storm and were treated successfully with oral quinidine, an "endangered species" drug.