3.9: Management of HF beyond medication

Device treatment

Prevention of sudden death is an important goal in HF because approximately half of the deaths occur suddenly, and many of these are related to ventricular arrhythmias. Implantable cardioverter-defibrillator (ICD) therapy is recommended in survivors of cardiac arrest , irrespective of EF, when life expectancy is >1 year. (Class I recommendation, level of evidence A).

In symptomatic HF patients (NYHA class II-III) with an EF ≤35% after more than 3 months of pharmacological treatment and a life expectancy >1 year, prophylactic ICD implantation is recommended in patients with ischemic etiology (Class I recommendation, level of evidence A) and non-ischemic etiology (Class I recommendation, level of evidence B).

Cardiac resynchronization therapy (CRT) is indicated in patients with symptomatic heart failure with one type and severity of ventricular conduction delay (LBBB, QRS ≥120 msec), and preferably in patients with sinus rhythm. The responder rate (improvement of at least 5% EF) is about 70%. Recommendation for use of this therapy differs according to heart rhythm, NYHA class, QRS duration and morphology, and LVEF. This is depicted in the Figure 3.9.1.

Figure 3.9.1: Flowchart for CRT

Timing of ICD implantation

Figure 3.7.2 offers recommendations to which patients should receive ICD treatment. In this flowchart, the timing of the placement has not been defined completely. In most patients, it should be safe to wait for their ICD whilst receiving (pharmacological) treatment as events typically occur after 6-12 months.[11] An exception to this rule is the group of high risk patients (i.e. patients with major myocardial infarction (MI), who have extensive fibrosis on the MRI or NSVT despite optimal pharmacological treatment); an ICD implantation should not be postponed too long in these patients. Early (within 40 days after event) ICD placement after an acute myocardial infarction has not been shown to reduce mortality, because the patients most at risk of sudden death are also the patients most at risk of death due to heart failure.[12][13][14] For this reason, prophylactic ICD treatment is recommended only after 40 days in post-infarct patients who have an EF < 35%. For non-ischemic heart failure patients, three months is considered a safe waiting time for an ICD. There are, however, also higher risk patients among this group, and a decision should be made for each patient on an individual basis.[15]

Heart transplantation and Left Ventricular Assist Devices

When a patient has severe and progressive HF, his or her prognosis is grim. Considering the paucity of donor hearts, the waiting list for heart transplantation may be long and early consideration of heart transplantation is part of the treatment strategy in HF. Average 2-year survival rates after cardiac transplantation are approximately 80%. A patient in NYHA class III should be evaluated with an exercise test for maximal oxygen uptake, in order to consider further steps. Indication for heart transplantation includes a VO_2max < 14 ml/min/kg.[16]

Exclusion criteria are pulmonary hypertension (risk of immediate RV donor failure), severe comorbidity, and diabetes mellitus with organ damage. Left Ventricular Assist Devices are more commonly used as a bridge to transplantation, when the patient in on a waiting list. They have evolved from pulsatile to continuous flow pumps, with less complications and a longer durability. Often Left Ventricular Assist Devices become destination therapy.

Management of HF patients with preserved LVEF (HFPEF)

To date, no evidence exists of any treatment reducing morbidity or mortality in this patient group. With the aim of controlling water and sodium retention and to decrease breathlessness and edema, diuretics are prescribed to HFPEF patients. Furthermore, ACE-I, Angiotensin II blockers and/or beta blockers may be considered. The CHARM trial including 3023 HF patients with preserved EF, showed angiotensin II blockade (candesartan) to have a moderate effect on hospital admission but showed no effect on the risk of cardiovascular death.[17]

Prognosis

The life expectancy of a patient with heart failure is determined by age, NYHA class, LVEF, normal level of sodium, systolic blood pressure, use of medication and use of ICD or CRT-D (Seattle Heart failure score). The mean yearly annual mortality is approximately 10%, varying from <6% per year when a normal LVEF is identified, to > 14% per year with an EF of <15%. Trials with medication illustrate that the (short term) benefit of medication is highest when the NYHA class is higher (Figure 3.9.2).[18]

Figure 3.9.2: Two-year mortality in landmark contemporary clinical heart failure trials (from Cleland et al)