Costanzo.qxp 23/7/08 04:27 Page 68
Heart Failure
off as refilling occurs. After ultrafiltration, the decreased venous pressure further space between these fibers, and exits through a port near the top of the filter
enhances the net transcapillary pressure gradient change, favoring interstitial case. Ultrafiltrate then passes through a blood-leak detector. Ultrafiltrate
fluid reabsorption. sequentially passes through the ultrafiltrate pressure sensor, ultrafiltrate pump,
and collecting bag that is suspended from the weight scale. Treatment can be
If the ultrafiltration rate is limited to 500–1,000ml/hour for only a few hours, performed by any nurse trained in the use of the device.
heart rate, blood pressure, and systemic vascular resistance remain
unchanged.
10
Cardiac output either rises or remains stable. Pulmonary Three pilot trials of intermittent peripheral veno–venous ultrafiltration have
capillary wedge pressure is unchanged or decreased. Right atrial pressure and been published. In the first study, in 21 fluid-overloaded patients, removal of
pulmonary vascular resistance fall. An improved ejection fraction and a an average of 2,611±1,002ml over 6.4±1.5 hours reduced weight from
decreased radiographic cardiothoracic ratio have also been described.
10
92±17kg to 89±17kg (p<0.0001), and also reduced congestion without
Advantages of intermittent isolated ultrafiltration include the avoidance of an changes in heart rate, blood pressure, electrolytes, or hematocrit.
21
arterial puncture and the short exposure to systemic anticoagulation.
Disadvantages include the need for dialysis equipment and personnel, and the The aim of the second study was to determine whether ultrafiltration with the
removal of large amounts of fluid in a short time period. Hemorrhage from Aquadex System 100 before intravenous diuretics in patients with
anticoagulation and extracorporeal blood pump complications, such as air decompensated HF and diuretic resistance resulted in euvolemia and hospital
embolism, can occur. discharge in three days without hypotension or worsening renal function.
Ultrafiltration was initiated within 4.7±3.5 hours of hospitalization and before
Intermittent isolated ultrafiltration has been described in more than 100 intravenous diuretics in 20 HF patients with volume overload and diuretic
patients with NYHA class IV refractory HF.
20
Of 52 patients treated with slow resistance (age 74.5±8.2 years; 75% ischemic disease; ejection fraction
isolated ultrafiltration, 13 died in less than one month during treatment 3±15%), and continued until euvolemia. An average of 8,654±4,205ml was
(non-responders), 24 experienced both cardiac and renal improvement removed with 2.6±1.2 eight-hour ultrafiltration courses (eight hours each).
(responders) for either less than three (n=6) or more than three months Twelve patients (60%) were discharged within three days. One patient was
(n=18), and 15 (partial responders) had hemodynamic improvement but re-admitted within 30 days and two patients within 90 days for reasons
worsening renal function requiring either long-term weekly ultrafiltration unrelated to recurrent volume overload. Weight (p=0.006), Minnesota Living
(n=8), continuous ambulatory peritoneal dialysis (n=1), or intermittent renal with Heart Failure scores (p=0.003), and global assessment (p=0.00003) were
replacement therapy (n=6). Adequate diuresis was restored within one month improved after ultrafiltration at 30 and 90 days. B-type natriuretic peptide
in 24 of the 39 responders and partial responders. Four of the 15 partial levels were decreased after ultrafiltration (from 1,236±747 to 988±847pg/ml)
responders had sufficient recovery of renal function to undergo heart and at 30 days (816±494pg/ml; p=0.03). Blood pressure, renal function, and
transplantation within three to nine months. Thus, intermittent ultrafiltration medications were unchanged. Thus, in HF patients with volume overload
can be used to treat HF refractory to maximally tolerated medical therapy. and diuretic resistance, early ultrafiltration before intravenous diuretics
Restoration of diuresis and natriuresis after intermittent ultrafiltration effectively and safely decreases length of stay and re-admissions. Benefits
identified patients with recoverable cardiac functional reserve. Intermittent persisted at three months after treatment.
22
isolated ultrafiltration is valuable in partial responders because it improves
quality of life and may be used as a bridge to heart transplantation. The high The aim of the third study was to compare the safety and efficacy of
short-term mortality is consistent with the poor prognosis of advanced HF. ultrafiltration using the Aquadex System 100 device with the efficacy and
safety of intravenous diuretics in decompensated HF patients. Compared with
A new device, the Aquadex™ System 100 (CHF Solutions, Minneapolis), the 20 diuretic-treated patients, the 20 patients randomized to a single
permits both the withdrawal of fluid and blood return through peripheral veins eight-hour ultrafiltration session had greater median fluid removal (2,838
(see Figure 1). However, central venous access remains an option. Fluid removal versus 4,650ml; p=0.001) and weight loss (1.86 versus 2.5kg; p=0.24).
can range from 10 to 500ml/hour; blood flow can be set at 10–40ml/minute, Ultrafiltration was well tolerated and not associated with adverse
and total extracorporeal blood volume is only 33ml. The device consists of a hemodynamic or renal effects. Thus, early ultrafiltration in decompensated HF
console, an extracorporeal blood pump, and venous catheters. The console patients results in greater fluid removal and improvement of congestion than
controls blood removal rates and extracts ultrafiltrate at a user-set maximum those achieved with intravenous diuretics.
23
The findings of these studies
rate. The device is designed to monitor the extracorporeal blood circuit and to stimulated the design and implementation of the Ultrafiltration Versus
alert the user to abnormal conditions. Ultrafiltrate drains into a bag. Blood is Intravenous Diuretics for Patients Hospitalized for Acute Decompensated
withdrawn from a vein through the withdrawal catheter. Tubing connects Heart Failure (UNLOAD) trial.
24
This study was designed to compare the safety
the withdrawal catheter to the blood pump. Blood passes through the and efficacy of veno–venous ultrafiltration with standard intravenous diuretic
withdrawal pressure sensor just before it enters the blood pump tubing loop. therapy for hospitalized HF patients with ≥2 signs of hypervolemia. Two
During operation, the pump loop is compressed by rotating rollers that propel hundred patients (mean age 63±15 years; 69% men; 71% ejection fraction
the blood through the tubing. After exiting the blood pump, blood passes ≤40%) were randomized to ultrafiltration or intravenous diuretics. At 48
through the air detector and enters the hemofilter. The hemofilter is bonded to hours, weight (5±3.1 versus 3.1±3.5kg; p=0.001) and net fluid loss
a clip-on cartridge that mounts onto the ultrafiltrate pump raceway on the side (4.6 versus 3.3 liters; p=0.001) were greater in the ultrafiltration group.
of the console. Blood enters the filter through a port on the bottom, exits Dyspnea scores were similar. At 90 days, the ultrafiltration group had fewer
through the port at the top of the filter, and passes through the infusion patients rehospitalized for HF (16 of 89 [18%] versus 28 of 87 [32%];
pressure sensor before returning to the patient. Inside the hemofilter there is a p=0.037), HF rehospitalizations (0.22±0.54 versus 0.46±0.76; p=0.022),
bundle of hollow fibers. The ultrafiltrate passes through the fiber walls, fills the rehospitalization days (1.4±4.2 versus 3.8±8.5; p=0.022) per patient, and
68 US CARDIOLOGY
Page 1  |  Page 2  |  Page 3  |  Page 4  |  Page 5  |  Page 6  |  Page 7  |  Page 8  |  Page 9  |  Page 10  |  Page 11  |  Page 12  |  Page 13  |  Page 14  |  Page 15  |  Page 16  |  Page 17  |  Page 18  |  Page 19  |  Page 20  |  Page 21  |  Page 22  |  Page 23  |  Page 24  |  Page 25  |  Page 26  |  Page 27  |  Page 28  |  Page 29  |  Page 30  |  Page 31  |  Page 32  |  Page 33  |  Page 34  |  Page 35  |  Page 36  |  Page 37  |  Page 38  |  Page 39  |  Page 40  |  Page 41  |  Page 42  |  Page 43  |  Page 44  |  Page 45  |  Page 46  |  Page 47  |  Page 48  |  Page 49  |  Page 50  |  Page 51  |  Page 52  |  Page 53  |  Page 54  |  Page 55  |  Page 56  |  Page 57  |  Page 58  |  Page 59  |  Page 60  |  Page 61  |  Page 62  |  Page 63  |  Page 64  |  Page 65  |  Page 66  |  Page 67  |  Page 68  |  Page 69  |  Page 70  |  Page 71  |  Page 72  |  Page 73  |  Page 74  |  Page 75  |  Page 76  |  Page 77  |  Page 78  |  Page 79  |  Page 80  |  Page 81  |  Page 82  |  Page 83  |  Page 84