Summary
HHH study is a randomized controlled trial conducted in Italy, Poland and UK enrolling patients with chronic heart failure (CHF; LVEF <35%, NYHA class II-IV) in 2 arms (usual clinical practice and home-care strategy).
‘Home care strategy’ patients have been randomized into:
1) normal clinical practice supplemented by monitoring using conventional telephone contacts,
2) as strategy 1 plus periodic telemonitoring of vital signs
3) as 2° strategy plus periodic 24h ECG, respiration and physical activity (NICRAM) recording which is used in care plan.
Enrolment in the 11 Centers (5 in Italy, 3 in UK and 3 in Poland) has been over 12 months with a further 12 months follow-up. Objectives are:
1) To determine if different strategies of home-care telemonitoring:
(i) simple voice contact by telephone plus routine hospital care:
(ii) as (i) plus intermittent monitoring of vital signs:
(iii) as (ii) plus periodic continuous monitoring of ECG, respiration and activity, affect hospital admissions, improve patient sense of well-being, and reduce overall costs of medical care.
2) To define the prevalence and the clinical impact of breathing disorders, arrhythmias and abnormalities of HRV in the occurrence of acute periods of instability when on optimal therapy.
3) To evaluate in the home setting a new system for continuous monitoring of cardio-respiratory signals plus physical activity with tele-transmission of recorded data embedded in an interactive voice response based telehealth system.
The primary end-point will be total bed-days occupancy for heart failure in acute medical / surgical beds. Secondary end-points will be bed-days occupancy for all cause and for cardiovascular events (death, HF, arrhythmias, unstable angina, myocardial infarction, stroke and cardiovascular procedures), measures of patient well-being (death, hospital bed days, symptom score and QoL), change in therapy, costs of care and cost-effectiveness.
Exploratory end-points will include: frequency of Cheyne-Stokes respiration (apnoea/ hypopnoea index and total time during night and day) and predicting role of heart rate variability parameters. A separate analysis on the value of pre-discharge NICRAM in predicting early (<1 month) unplanned readmission and cardiac events will also be performed in patients of both groups.
From July 2002 to July 2004, 461 HF patients were enrolled in 11 centers (age 60±11 yrs, NYHA class 2.4±0.6, LVEF 29±7%) and follow-up was completed in July 2005. In Italy, Poland and UK 82%, 75% and 93% respectively, of practicable vital signs transmissions have successfully been carried out by the patients, for a total of 50217 parameters and 686 voice messages received. In the three countries, 96%, 85% and 99% of NICRAM recordings, have been correctly transmitted, and 77% were eligible for the study (i.e. >2.5 hours of good quality data during the night), for a total of 1296 home recordings.
We hypothesise that long-term telemonitoring of NICRAM will allow early identification of clinical deterioration, earlier optimisation of treatment, better survival, improve QoL and encourage self care in HF patients. Such a tele-monitoring system, if proven to be effective and practical will then be applicable to several other clinical situations (e.g. rehabilitation post-MI and stroke, obstructive sleep apnoea, chronic lung disease.