It’s about time we did a PD topic. The next journal club will discuss two recent Italian papers concerning the use of peritoneal dialysis to achieve ultrafiltration in refractory heart failure but without ESRD. Diuretic resistance is common in patients with CKD and chronic heart failure and using PD in this setting is attractive given its hemodynamic tolerability. The idea of using peritoneal UF for maintenance therapy is not new but the evidence base is weak, consisting primarily of case reports.

The Bertoli study is a retrospective observational study in 10 centers including patients with severe HF resistant to maximal medical therapy. The aim was to evaluate the clinical indications, protocols employed and long-term outcomes.

Patients:

48 consecutive patients in the 10 centers between 1 January 2006 and 31 December 2010 who were followed for at least 6 months.
PD used exclusively for fluid overload (i.e. not ESRD)

Notable points:

In 30 patients, a single overnight exchange with Icodextrin was used, 13 used APD/CCPD.
1 patient had an eGFR <10 ml/min, who arguably should have been excluded, although native eGFR improved to 24 ml/min after initiation of PD.
At 12 months, NYHA CHF class fell by at least 1 in 41 patients (85%).
Significant improvements were seen in both LVEF and pulmonary artery pressures during follow up.
Hospitalization rate improved compared to pre-PD.
Peritonitis rate of 1 per 45 patient months.
8 drop outs in first year (7 deaths, 1 switched to hemodialysis).

In the discussion, the authors mention an interesting fact which I must admit I was not aware of, and which may explain some of the benefit of PD in this setting. Peritoneal UF contains a [Na] of 130-150 mmol/L compared to average diuretic-induced urine of 50-100 mmol/L.

The second study was a systematic review, also from Italian authors, included 14 studies, 6 of which were prospective with 471 patients. Mean age was 71 and a range of eGFRs (and methods to calculate eGFR) was included.

Single-exchange icodextrin was used in 51% of cases
UF volumes were given which varied between 390-1,180 ml/day (higher end of the range with Icodextrin).
Improvements in NYHA class were reported as well as decreased hospitalizations
Overall peritonitis rate 1 episode per 40 patient months (equivalent of)
Survival was reported ranging from 47-95% at one year.
The patients, protocols and outcomes were widely variable, leading to difficulty drawing hard conclusions based on the results.

My own experience with peritoneal UF in refractory heart failure is minimal (n=2) but I like the idea, particularly using one Icodextrin exchange (these patients appeared to do as well as more aggressive regimes in the Bertoli et al study). In practice, most patients have added co-morbidities and frailty leading to unsuitability for PD, which obviously requires a fair degree of independence and self managed care. The evidence presented remains weak, being a retrospective observational study and a systematic review of similar studies. However, for select patients, where other treatments have failed, it appears to be a well tolerated, efficacious treatment option.