Other devices—an implantable cardioverter defibrillator (ICD) or a biventricular pacer—should also be considered for patients at stage D, as well as stage C patients who are at increased risk of sudden death despite maximal drug therapy.6 Patients who have had a previous MI or ventricular arrhythmia are at risk for a repeat episode.6
Use of an ICD can reduce mortality by 23% in selected patients.26 Potential candidates for the device are patients who have an ejection fraction of <30%, mild to moderate symptoms, and a life expectancy of at least 1 year.6
Biventricular pacing, also known as cardiac resynchronization therapy (CRT), has been found to improve the quality of life, functional status, and exercise capacity in some patients with advanced disease. CRT, which reduces symptoms of HF and improves cardiac function by reestablishing the mechanical sequence of ventricular activation and ventricular contraction, has also been associated with reductions in hospitalization and death from progressive HF.27,28
The Comparison of Medical Therapy, Pacing, and Defibrillation in Heart Failure (COMPANION) trial demonstrated a 20% reduction in the 12-month risk of death or hospitalization from any cause with CRT, and the Cardiac Resynchronization-Heart Failure (CARE-HF) trial established that patients receiving CRT had a significantly lower risk of death than those receiving medical therapy alone (40% reduction).29,30
However, not all patients with HF have problems with conduction delay that result in a dyssynchronous heart beat. CRT is indicated only for patients who are in sinus rhythm and have:
- NYHA class III or IV HF
- an ejection fraction of <35%
- a prolonged QRS complex (>120 m/sec), and
- continued symptoms despite maximal medical therapy.6
Under these criteria, approximately 10% of patients with HF would qualify for CRT.31 The restrictive criteria are due, in part, to the fact that this modality is relatively new and has been studied only in a small subset of patients.
Options for patients who are running out of them
For acutely decompensated hospitalized patients with volume overload, ultrafiltration (UF) is a useful alternative to diuretics. UF uses high pressure to “force” volume through the kidneys;32,33 the technique maximizes diuresis, and is best suited for patients who have significant renal dysfunction or are not responding to standard diuretic therapy. UF makes it easier to remove the desired amount of fluid, and has a positive impact on pulmonary wedge pressure and cardiac output.34 Its use in diuretic-resistant patients can decrease the length of stay and produce positive clinical benefits that may last up to 3 months.34
There are also a number of experimental strategies, surgical and otherwise. Among them are:
Cardiac wrap surgery, in which the heart is encased in a mesh bag attached with stitches, in an attempt to stop the progression of end-stage HF by preventing further dilation;25
Ventricular restoration surgery, a procedure in which scar tissue caused by MI is removed from the ventricular muscle and the left ventricle is reshaped and its size reduced in an attempt to restore some of the heart’s pumping ability;25 and
Enhanced external counterpulsation, or EECP, a noninvasive technique in which pressure cuffs are placed on the calves, thighs, and buttocks and inflated and deflated in an attempt to increase blood flow back to the heart.25
Correspondence
Randy Wexler, MD, MPH, FAAFP, The Ohio State University, B0902B Cramblett Hall, 456 W. 10th Avenue, Columbus, OH 43210; randy.wexler@osumc.edu