Continuous Ambulatory Peritoneal Dialysis and the Heart

Objective

To review clinical research pertaining to continuous ambulatory peritoneal dialysis (CAPD) and the heart.

Data Sources

A Medline computer search was employed to identify appropriate references from 1970 1994. Indexing terms were: continuous ambulatory peritoneal dialysis, hemodialysis, heart or cardiac, left ventricle, coronary artery disease, and survival. English and non-English language abstracts were scrutinized.

Study Selection

Forty-six studies were reviewed and utilized. Numerical data extracted are reported in this review as they were reported in the original article.

Results

This review provides a broad-based survey of studies pertaining to CAPD and the heart. Most of the studies relate to CAPD and left ventricular structure or function. Little information exists concerning CAPD and coronary artery disease, valvular disease, pericardial disease, and cardiac arrhythmias. Studies pertaining to patient survival on CAPD identify coronary artery disease and congestive heart failure as major risk factors, but in-depth quantification of these cardiovascular disorders is lacking in the literature.

Conclusions

CAPD is capable of decreasing left ventricular (LV) volume and improving LV systolic function in patients with L V enlargement and those with L V systolic dysfunction. The effect of CAPD on left ventricular hypertrophy (LVH) and LV diastolic function is variable. CAPD produces symptomatic improvement in patients with refractory congestive heart failure, but its effect on survival in such patients is uncertain. Atherogenic lipid abnormalities occur in CAPD patients. The clinical significance of these abnormalities is uncertain. Coronary artery bypass surgery can be performed safely and effectively on CAPD patients. CAPD is not arrhythmogenic. Survival of CAPD patients is similar to that of hemodialysis patients except in elderly diabetics for whom it is slightly lower.

Coronary artery bypass grafting in patients on maintenance dialysis: is peritoneal dialysis a risk factor of operative mortality?

BACKGROUND

Increasing numbers of patients on dialysis are undergoing coronary artery bypass grafting (CABG). We undertook this retrospective study to identify risk factors of operative mortality in dialysis patients who underwent CABG.

PATIENTS AND METHODS

We performed retrospective analysis of 105 patients who were on dialysis for at least two months before surgery and who underwent CABG in Toronto General Hospital from 1997 to 2006. Using prospectively collected data from the Division of Cardiovascular Surgery Database of Toronto General Hospital, we collected data on comorbidities, procedures, modality change during hospitalization, and operative outcomes. Logistic regression was used to assess risk factors of operative mortality.

RESULTS

One hundred and five maintenance dialysis patients (40 PD and 65 HD) who met the inclusion criteria were studied. Overall in-hospital mortality was 7.6%. Atrial fibrillation and pneumonia occurred in 16.2 and 9.5%, respectively, of all dialysis patients. Among PD patients, rates of post-operative dialysate leak and peritonitis were 10 and 12.5%, respectively. Among HD patients, 4.6% experienced post-operative AV access thrombosis. Logistic regression showed older age (>or=70 years) and peritoneal dialysis are independent risk factors of operative mortality.

CONCLUSION

In this retrospective study, older patients on PD had higher operative mortality than HD patients. These findings suggest extra care should be taken when CABG is considered for PD patients over 70 years old. In this study we could not identify the reason(s) for the high mortality of elderly peritoneal dialysis patients undergoing CABG.

Early and long term results of coronary artery bypass grafts in patients with dialysis dependent renal failure

OBJECTIVE

Coronary artery disease is the main cause of mortality and morbidity in patients on renal therapy replacement. The aim of this study was to define peri-operative risk and long term results of coronary artery bypass grafts (CABG) in dialysis patients.

METHODS

this retrospective study included 82 patients in chronic dialysis who underwent CABG between 1978 and 1997. The mean age was 61+/-10 years (range 28-81 years), 84% of the patients were male and the average duration of dialysis was 57 months (range 1-148 months). Combined procedures were carotid endarterectomy in one case, left ventricular aneurysm resection in one and valvular replacement in 10 (nine aortic and one mitral replacements). The operation was elective in 42 patients (51 %) and urgent in the others. Previous myocardial infarction was found in 37 patients (45%) and left ventricular ejection fraction (LVEF) at less than 45% in 15 patients (18%); 23 patients (28%) were in NYHA class III or IV and regarding angina functional status, 77% in CCS class 3 or 4. Follow-up was complete. Statistical analysis included 30 and pre and peri-operative data. Statistical analysis used Chi-square analysis or Fisher's exact test, and the Mann-Whitney test when appropriate. The estimated probability of survival, including postoperative mortality, was calculated by the method of Kaplan-Meyer, and the Log-Rank test used to compare the results.

RESULTS

the hospital mortality was 14.6 % (n = 12). Ischemic time and ECC time were significantly lengthened in dead patients (P = 0.01). Moreover, use of internal mammary artery was directly related to lower hospital mortality (P = 0.02). For previous myocardial infarction, LVEF at less than 45%, diabetes and combined procedure, a P-value of < or = 0.1 was calculated. The follow-up ranged from 1 to 140 months (mean 36 months). There were 39 late deaths. The survival rates (included hospital mortality) were 71+/-5%, 56+/-6% and 39+/-6% at 1, 3 and 5 years, respectively. All surviving patients improved their functional status and had symptomatic relief. Statistical analysis showed significant difference in favor of long term survival for patients younger than 60 years, LVEF > 45% and NYHA class I or II.

CONCLUSION

these data confirm that CABG in patients with renal replacement therapy is associated with an high operative and long term mortality. However it allows an improvement of functional status, and so, let possible duration of dialysis. It may be expected that more active prevention and detection of coronary disease might improve these results.

Open heart operations after renal transplantation

BACKGROUND

Because of the increasing number of renal transplantations performed, secondary cardiac operations in these patients are discussed concerning their impact on patient and graft survival.

METHODS

We reviewed our experience in 45 patients (33 male and 12 female) who underwent open heart operations after previous renal transplantation. Thirty-one patients (group I) received coronary artery bypass grafting and 14 (group II) underwent valve replacement. Mean age at the time of operation was 55 +/- 9 years. The interval between renal transplantation and cardiac operation was 57 +/- 39 months (range, 5 days to 174 months). All patients had functioning renal allografts with preoperative serum creatinine levels ranging from 100 to 338 mol/mL (mean +/- standard deviation, 195 +/- 86).

RESULTS

Overall early operative mortality (30 days) was 8.8% (group I, 1 patient; group II, 3 patients). Underlying causes of death were septic endocarditis (n = 2, group II), necrotizing enterocolitis (n = 1, group I), and myocardial infarction (n = 1, group II). One further patient in group II also died of septic endocarditis after 69 days (in-hospital death). The mean follow-up of the 40 surviving patients was 44 +/- 31 months. There was another late death (24 months postoperatively) caused by coagulopathy. Four patients had returned to hemodialysis at intervals of 27 to 83 months (mean, 51 months) because of renal transplant failure. In all patients, the function of the renal allograft was not impaired by open heart operation.

CONCLUSIONS

Open heart operations in renal transplant recipients have acceptable mortality and morbidity rates. In almost all patients, function of the transplanted organ can be maintained at the preoperative level.

Comparison of clinical outcomes of coronary artery bypass grafting and percutaneous transluminal coronary angioplasty in renal dialysis patients

BACKGROUND

The leading cause of death in chronic renal dialysis patients is cardiovascular disease. As the number of dialysis patients increases, we are encountering more patients with severe ischemic heart disease requiring coronary intervention.

METHODS

A retrospective analysis was performed of the short- and long-term clinical results in 23 coronary artery bypass grafting patients and 20 coronary angioplasty patients undergoing chronic renal dialysis.

RESULTS

Among coronary bypass grafting patients, there were no hospital deaths. The graft patency rate was 100% for arterial grafts. There were four late deaths and four cardiac events. In coronary angioplasty patients, the lesion success rate was 76%. There were no hospital deaths and three major complications. The restenosis rate was 70%. There were two late deaths and 14 cardiac events. The 5-year cardiac event-free rate was 70% in coronary bypass grafting patients, significantly better than 18% in coronary angioplasty patients (p < 0.001).

CONCLUSIONS

Coronary artery bypass grafting in chronic renal dialysis patients can be accomplished with a better short- and long-term outcome than coronary angioplasty, through an intensive perioperative dialysis program and extensive use of arterial grafts.

Coronary artery bypass surgery in patients on maintenance dialysis: long-term survival

Coronary artery bypass grafting (CABG) can be performed with acceptable risk and results in symptomatic improvement in patients with end-stage renal disease (ESRD). However, the effect of CABG on long-term survival in these patients is unknown. We retrospectively identified 39 patients (group 1) with ESRD who underwent CABG for intractable angina between January 1975 and February 1987 while on maintenance dialysis. Thirty-nine dialysis patients (group 2) were also retrospectively selected for comparison and matched for age, sex, year of initiation, length of time on dialysis, and presence of diabetes mellitus and atherosclerotic heart disease at initiation of dialysis. Using life-table analysis, survival probability (with 95% confidence limits) was determined from the time of CABG for group 1 or after an equivalent period of time on dialysis for group 2. Two life-table analyses were performed; one with study end-points of death, withdrawal (renal transplantation, transfer to other dialysis facilities, and reoperation), and alive on dialysis; and a second with identical end points except that noncardiac deaths were treated as withdrawals. Coronary arteriography revealed severe three vessel disease, left ventricular dysfunction, and segmental wall motion abnormalities in most patients. A mean (+/- SD) of 2.56 +/- 0.75 vessels were bypassed with an operative mortality (30 days) of 2.6%. Mean follow-up after CABG in group 1 was 34.9 +/- 30.1 months, and in most patients functional classification improved. Mean follow-up for group 2 was 17.2 +/- 15.2 months. Two-year survival was 91.7% in group 1 and 51.4% in group 2 (P less than 0.05).(ABSTRACT TRUNCATED AT 250 WORDS)