Remote Follow-up of Patients Receiving Implantable Cardioverter Defibrillator for Prophylactic Therapy

The completed MADIT II study has shown that implantation of a cardioverter-defibrillator (ICD) in patients with a reduced left ventricular ejection fraction and a prior myocardial infarction reduces death from any cause. The probability of the 1st therapy due to ventricular tachyarrhythmia was about 34% within 3 years, with an increasing incidence from year 1 to 3. With a 3-month ICD-follow-up scheme, as it is in the standard ICD therapy, the majority of patients is followed more closely than necessary with respect to anti-tachyarrhythmia ICD therapy.

A Home Monitoring (HM) function has been integrated into several ICD models from Biotronik (Berlin , Germany), for close remote monitoring of ICD patients. The HM function automatically transmits predefined parameters on a daily basis from the implanted devices to a web-based platform accessible only by registered patients' physicians. These data may substitute in-clinical follow-up controls.

The objective of our study is to compare a standard 3-month follow-up scheme and a 12-month follow-up scheme using HM in ICD recipients with the "MADIT II indications". The comparison should be made with respect to the difference in follow-up burden and the associated costs, and regarding possible impact of the remote follow-up via HM on all cause mortality, hospitalization, and patients' quality of life.

The patients should receive single- or dual-chamber ICD models with the HM function.

The pre-hospital-discharge protocol comprises standard ICD follow-up + specific ICD programming, and activation of the HM function. The 1st standard follow-up visit is performed 3 months after the pre-discharge control. At this visit the patients are randomized to 3- vs. 12-month follow-up scheme. For the 3-month follow-up group, routine visits are scheduled at 6, 9, 12, 15, 18, 21, 24, and 27 months after patient discharge. For the 12-month (remote) follow-up group, routine visits are scheduled at 15 and 27 months after discharge. In either group, additional visits are scheduled on patient demand, due to device or lead problems, or due to the following Cardio Report (Home Monitoring) findings: Elective ICD replacement point, the 1st shock after discharge, an ineffective shock, ineffective anti-tachycardia pacing, ventricular pacing impedance outside the pre-defined range, shock impedance lower than 25 Ohm or greater than 110 Ohm, frequent arrhythmia episodes (according to pre-specified criteria).

Inclusion criteria

Indication for implantation of an implantable cardioverter-defibrillator (ICD) according to the patient selection criteria used in the MADIT-II trial:

• Myocardial infarction 1 month or more prior to entry
• Ejection fraction of 30% or less within 3 months before entry

Exclusion criteria

• NYHA functional class IV
• Coronary revascularization later than 5 days after ICD implantation
• First myocardial infarction within the past month
• Advanced cerebrovascular disease
• Any condition with a likelihood of death within the next 12 months
• Pacing indication
• Conventional ICD indication (i.e., criteria other than MADIT II)
• Living in an area with insufficient GSM coverage