Pulmonary Hypertension in Dialysis Patients

The significance of volume overload in the development of pulmonary arterial hypertension in continuous ambulatory peritoneal dialysis patients

INTRODUCTION

The underlying pathophysiology of pulmonary arterial hypertension (PAH) is multifactorial; however, the significance of chronic volume overload and its subsequent effects on cardiac function must be studied thoroughly. The main objective of this study was to determine the predictive parameters of PAH in patients undergoing continuous ambulatory peritoneal dialysis (CAPD) using transthoracic echocardiography (TTE) and bioimpedance analysis (BIA).

METHODS

In this cross-sectional study, 43 eligible CAPD patients were chosen. The patients were examined by TTE and BIA before the morning dialysis session, and baseline patient characteristics, echocardiography, and BIA parameters were recorded.

RESULTS

Sixteen (37.2%) patients were diagnosed with PAH. Patients with PAH had significantly greater left atrial diameter (LAD), left ventricular mass index (LVMI), and higher grades of diastolic dysfunction (DDF). Systolic pulmonary artery pressure (sPAP) correlated with LAD (p < 0.001, r = 0.566), interventricular septal diameter (IVSD) (p = 0.004, r = 0.425), LVMI (p = 0.030, r = 0.323), and extracellular water/total body water (ECW/TBW) ratio (p = 0.002, r = 0.458).

CONCLUSION

Two volume status-related parameters including ECW/TBW ratio and inferior vena cava (IVC) expiratory diameter, and cardiac-related TTE findings such as LAD and DDF were predictors of sPAP in CAPD patients.

Development and validation of a risk nomogram model for predicting pulmonary hypertension in patients with stage 3-5 chronic kidney disease

OBJECTIVES

The occurrence of pulmonary arterial hypertension (PAH) can greatly affect the prognosis of patients with chronic kidney disease (CKD). We aimed to construct a nomogram to predict the probability of PAH development in patients with stage 3-5 CKD to guide early intervention and to improve prognosis.

METHODS

From August 2018 to December 2021, we collected the data of 1258 patients with stage 3-5 CKD hospitalized at the Affiliated Hospital of Xuzhou Medical University as a training set and 389 patients hospitalized at Zhongda Hospital as a validation set. These patients were divided into PAH and N-PAH groups with pulmonary arterial systolic pressure ≥ 35 mmHg as the cutoff. The results of univariate and multivariate logistic regression analyses were used to establish the nomogram. Then, areas under the receiver operating characteristic curve (AUC-ROCs), a calibration plot, and decision curve analysis (DCA) were used to validate the nomogram.

RESULTS

The nomogram included nine variables: age, diabetes mellitus, hemoglobin, platelet count, serum creatinine, left ventricular end-diastolic diameter, left atrial diameter, main pulmonary artery diameter and left ventricular ejection fraction. The AUC-ROCs of the training set and validation set were 0.801 (95% confidence interval (CI) 0.771-0.830) and 0.760 (95% CI 0.699-0.818), respectively, which showed good discriminative ability of the nomogram. The calibration diagram showed good agreement between the predicted and observed results. DCA also demonstrated that the nomogram could be clinically useful.

CONCLUSION

The evaluation of the nomogram model for predicting PAH in patients with CKD based on risk factors showed its ideal efficacy. Thus, the nomogram can be used to screen for patients at high risk for PAH and has guiding value for the subsequent formulation of prevention strategies and clinical treatment.

Pulmonary Hypertension in Patients Starting Peritoneal Dialysis

BACKGROUND

Cardiovascular complications are the major cause of morbidity and mortality in patients with chronic kidney disease (CKD). One such complication is pulmonary hypertension (PH). Its prevalence in patients in peritoneal dialysis (PD) varies from 12.6-41.7% and its related factors are not well known. The main objective of this multicenter study was to determine the prevalence of PH and its risk factors in patients starting in PD.

METHODS

Patients incident in PD were studied. Clinical, biochemical, and PD parameters were evaluated. A transthoracic echocardiography was performed and the evaluated according to the American Society of Echocardiography. Systolic pulmonary artery pressure (sPAP) was calculated with tricuspid regurgitation gradient and PH considered if pulmonary artery pressure was ≥35 mmHg.

RESULTS

There were 105 men and 72 women included in the study (aged 53.7 ± 12.8 vs. 52.9 ± 15.5 years). PH was found in 69 patients (38.98%), they had sPAP of 49.05 ± 13.80 vs. 18.81 ± 11.15 mmg, in patients without PH (p <0.001). Patients with PH tend to be more frequently men than women (42 vs. 35%, p = 0.33), and were younger (51.0 ± 14.9 vs. 55,1 ± 12.8 years; p = 0.05). Risk factor for PH were diastolic dysfunction of the left ventricle (LV) (OR = 1.46, 95% CI 1.094-1.973), left ventricular hypertrophy (LVF) (OR = 2.56, 95% CI 1.29-5.09); and residual renal function (RRF) was a protector factor (OR = 0.78, 95% CI 0.068-0.915).

CONCLUSIONS

Prevalence of PH in patient's incident in PD was 38%. The factors associated with PH were diastolic dysfunction of the LV and LV hypertrophy. RRF was a protector factor.

Prevalence of pulmonary hypertension in peritoneal dialysis patients: a meta-analysis

PURPOSE

Recent epidemiological evidence indicates an association between peritoneal dialysis (PD) patients and pulmonary hypertension (PH). However, the true prevalence of PH associated with PD has not been well described. So we conducted a meta-analysis to summarize the point prevalence of PH in adults with PD.

METHODS

PubMed, EMBASE, the Cochrane Collaboration, and the reference lists of relevant articles were searched to identify eligible studies. We used a random-effect meta-analysis model to estimate the prevalence of PH. We also performed sensitivity analyses and assessments of publishing bias.

RESULTS

Fourteen observational studies (n = 1483 participants) were included in this meta-analysis. The result of analysis in random-effect model showed that the pooled prevalence was 21% (95% CI 16-28), with significant heterogeneity between these studies (I² = 84%, p < 0.01). Sensitivity analysis further demonstrated the results to be robust. Besides, the Egger's test (p = 0.287) showed no significant publication bias.

CONCLUSIONS

PH is highly prevalent in patients with PD. Further studies are encouraged to definitively clarify the relationship between PH and PD.

Prevalence and risk factors for pulmonary arterial hypertension in end-stage renal disease patients undergoing continuous ambulatory peritoneal dialysis

BACKGROUND

Pulmonary arterial hypertension (PAH) is a major complication in renal failure patients, but very little information is available on the cardiovascular parameters in these patients. The prevalence and risk factors for PAH were systematically evaluated in patients with end-stage renal diseases (ESRD) undergoing continuous ambulatory peritoneal dialysis (CAPD).

METHODS

Between January 2010 and January 2014, 177 ESRD patients (85 males and 92 females) undergoing CAPD therapy were recruited. General data, biochemical parameters and echocardiographic findings were collected and PAH risk factors studied.

RESULTS

Study participants consisted of 65 patients (36.52%) with PAH (PAH group) and 112 patients without PAH (non-PAH group). The interdialytic weight gain, systolic blood pressure and diastolic blood pressure (DBP), mean arterial pressure and hypertensive nephropathy incidence in the PAH group were significantly higher than the non-PAH group (all p < 0.05). There were significant differences between PAH group and non-PAH group in C-reactive protein-positive rate, N-terminal pro-brain natriuretic peptide (NT-proBNP), hemoglobin, prealbumin and serum albumin levels (all p < 0.05). Compared with non-PAH group, PAH group showed significant increases in right ventricular internal diameter (RVID), right ventricular outflow tract diameter (RVOTD), main pulmonary artery diameter, left atrial diameter (LAD), left ventricular end-diastolic diameter, interventricular septal thickness, left ventricular mass index, early diastolic mitral annulus velocity and valve calcification incidence (all p < 0.05), and decreased left ventricular ejection fraction (LVEF), tricuspid annulus plane systolic excursion (TAPSE) and early diastolic blood flow peak and mitral annulus velocity (E/E') (all p < 0.05). Logistic regression analysis revealed that DBP, NT-proBNP, LAD, RVID, RVOTD, LVEF, TAPSE and E/E' are major risk factors for PAH.

CONCLUSION

We observed a high incidence of PAH in ESRD patients undergoing CAPD. Logistic regression analysis revealed that DBP, NT-proBNP, LAD, RVID, RVOTD, LVEF, TAPSE and E/E' are high-risk factors for PAH in ESRD patients undergoing CAPD.

The Relationship of Fluid Overload as Assessed by Bioelectrical Impedance Analysis with Pulmonary Arterial Hypertension in Hemodialysis Patients

Background

Pulmonary arterial hypertension (PAH) is common disease among hemodialysis (HD) patients and is associated with increased morbidity and mortality. However, its pathogenesis has not been completely elucidated. We aimed to evaluate the frequency of PAH in HD patients, as well as the relationship between fluid status and PAH.

Material/Methods

We enrolled 77 HD patients in this study. Multifrequency bioimpedance analysis (BIA) was used to assess fluid status. BIA was performed before and 30 min after the midweek of HD. Overhydration (OH)/extracellular water (ECW)% ratio was used as an indicator of fluid status. Fluid overload was defined as OH/ECW ≥7%. Echocardiographic examinations were performed before and after the HD. Pulmonary arterial hypertension was defined as systolic pulmonary artery pressure at rest (sPAP) higher than 35 mmHg.

Results

PAH was found in 33.7% of the HD patients. OH/ECW and the frequency of fluid overload were significantly higher in HD patients with PAH than those without PAH, whereas serum albumin and hemoglobin levels were significantly lower. sPAP level was significantly higher in HD patients with fluid overload than in those without fluid overload after hemodialysis session. Furthermore, sPAP, OH/ECW levels, and the frequency of PAH were significantly reduced after HD. We also found a significant positive correlation between sPAP and OH/ECW. Multivariate logistic regression analysis demonstrated fluid overload to be an independent predictor of PAH after HD.

Conclusions

PAH is prevalent among HD patients. This study demonstrated a strong relationship between fluid overload and PAH in HD patients.

Pulmonary hypertension associated with diffuse deposition of pentosidine in pulmonary arterioles

Diabetes induces advanced glycation end products (AGEs) that per se are not only a major cause of oxidative stress but also reduce the plasticity of connective tissue by pathological collagen cross-linking. We describe a case of severe pulmonary hypertension manifesting as a major diabetic complication. Impaired pulmonary arteriolar plasticity attributed to pentosidine, together with increased circulation volume by hyperosmotic pressure and reduction in myocardial compliance by multiple patchy fibrosis, may contribute to the clinical manifestation of severe pulmonary hypertension.

Pulmonary hypertension among patients on dialysis and kidney transplant recipients

Pulmonary arterial hypertension (PAH) is a serious cardiac complication among patients with end-stage renal disease (ESRD). We investigated pulmonary hypertension and its associated factors among patients who were on chronic dialysis and kidney transplant recipients. One hundred-eighty patients in three groups of hemodialysis (HD), peritoneal dialysis (PD), and kidney transplant were studied. Demographic and clinical characteristics and echocardiographic findings were evaluated. A multivariable linear regression model was used to find factors associated with pulmonary artery pressure. The mean age of participants was 50.3 ± 15.5 years and 63.9% were male. We found pulmonary hypertension (mean pulmonary artery pressure >25 mmHg) in 31.6%, 8.3%, and 5% of the patients on HD, PD, and transplant recipients, respectively (p < 0.001). In multivariate analyses, being on HD (B = 5.276, confidence interval [CI] 95%: 1.211-9.341), age (B = -0.319, CI 95%: -0.501 to -0.138), smoking (B = 11.631, CI 95%: 1.847-21.416), systolic cardiac dysfunction (B = 6.313, CI 95%: 3.073-9.554), and diastolic cardiac dysfunction (B = 5.227, CI 95%: 1.176-9.277) were associated with systolic pulmonary artery pressure. These results showed that pulmonary hypertension is a frequent cardiac complication among patients with ESRD, and the type of renal replacement therapy (HD), systolic and diastolic cardiac dysfunction, and smoking are associated with increased pulmonary artery pressure. Further studies with larger sample sizes and also prospective studies are recommended in this regard.