Heart failure is a major clinical problem that is increasing in magnitude and the cost of
management of heart failure is escalating. A significant part of this cost is related to
unplanned acute presentation to emergency departments and hospitalisation with worsening
shortness of breath due to increased fluid content in the lungs.
Many heart failure patients are already fitted with defibrillators to protect them from the
risk of fast heart rhythms and sudden death and are followed up in both the heart failure
clinics and defibrillator clinics. Recently some of the defibrillators fitted have been
equipped with an extra function that can detect and warn of changes in the fluid content of
the lungs very early even before the patient starts to complain of any shortness of breath
and before any signs of fluid overload are seen clinically. However, it is not known how to
deal with these warnings if they occur very early and it is not known whether a medical
intervention at his stage is beneficial to prevent progression and eventual hospital
admission. In the majority of cases, early warnings of this kind are ignored or this function
is disabled at implantation of the device.
The current study will involve patients who have already been fitted with a device with the
above capability. The investigators will use the new function to guide management of these
patients and compare their outcome with similar patients who are fitted with devices without
it. The investigators will attempt to manage early warnings by a predetermined increase in
medications in a group of patients and compare their clinical course to a similar group in
whom no action is taken.