How does personalising the heart-rate programming of cardiac implantable electronic devices in patients with heart failure due to reduced ejection fraction improve exercise time and promote better left ventricular function? (Dr Samuel Straw)

Background: The cardinal symptom of heart failure with reduced ejection fraction (HFrEF), exercise intolerance, is thought to be exacerbated by limited heart-rate (HR) rise.

However, increasing HR-rise in HFrEF patients with cardiac electronic implantable devices (CEID) using standard age-related algorithms does not improve exercise capacity.

In contrast, personalised HR-programming, guided by individuals’ non-invasive force-frequency-relationship (FFR) data does, whilst also promoting better left ventricular function.

Research Question: How does personalised HR-rise improve exercise capacity and preserve left ventricular function in HFrEF?

Objectives: Does 6mths of FFR-guided CEID-programming in HFrEF improve autonomic function, benefit left ventricular remodelling, and reduce neurohormonal activity?

Methods: Participants with HFrEF and a CEID will be randomly allocated to have the rate-adaptive algorithm programmed to: ‘personalised’; ‘standard’; or ‘rate-adaptive-off’ for 6mths.

In the ‘personalised’ group, the CEID will maintain HR within the patient’s optimal range guided by their FFR data. ‘Standard’ care will be age-guided HR-rise programming. In the ‘rate-response-off’ arm, rate-adaptive-mode will be deactivated.

Programming, testing, analysis of mechanistic outcomes (autonomic function, remodelling and circulating humoral factors) will be double-blind at baseline and 6mths.

Outcomes: This proposal will provide mechanistic information to explain the benefits of FFR-guided HR-management and guide the routine application of this approach.