If home telemonitoring reduces mortality in heart failure, is this just due to better guideline-based treatment?

To investigate, in a 'real-world' setting, the impact of home telemonitoring (HTM) compared to usual care on achieved dose of guideline-recommended medication, hospitalisation rate and mortality in patients with heart failure (HF).

We retrospectively analyzed data on 333 patients with HF referred to a HTM service supported by a nurse-specialist (mean age 71±12 years, mean left ventricular ejection fraction (LVEF) 36 ± 11% and median N-Terminal pro B-type Natriuretic Peptide (NT-proBNP) 2,972 ng/L (interquartile range (IQR): 1,447-7,801 ng/L)). Most patients (n = 278) accepted HTM (HTM-group) but 55 refused and received usual care (UC-group). In the HTM-group, weight, heart rate, blood pressure and symptom severity were measured daily.

At referral, respectively 90%, 90%, 67% and 94% of patients with LVEF ≤40% (n = 229) were treated with β-blockers (BB), angiotensin converting enzyme-inhibitors (ACE-I) or angiotensin receptor blockers (ARB), mineralocorticoid receptor antagonists (MRA) and diuretics, with rates similar between groups. After 6 months, prescription of BB (92% vs 83%), ACE-I/ARB (92% vs 90%) and MRA (68% vs 67%) did not differ significantly between groups. The proportions of patients who achieved ≥50% and ≥100% of target doses of BB, ACE-I/ARB and MRA were also similar in each group. However, during a median follow-up of 1094 days (IQR 767-1419) fewer patients who chose HTM died (33% vs 49%; P = 0.002).

Patients who choose HTM have a better prognosis than those who do not but this does not appear to be mediated through greater prescription of key HF medications.