Abstract and Introduction
Abstract
The importance of heart rate reduction in chronic stable heart failure (HF) has been highlighted in the recently published Systolic Heart Failure Treatment with If Inhibitor Ivabradine Trial (SHIFT). Patients with an elevated resting heart rate (HR) benefited from additional HR control despite optimal doses of beta blockers. The aim of this study was to define the prescribing patterns of beta blockers and the scope for additional HR control in a 'real life' HF population.
We conducted a retrospective analysis of two HF clinics, where patients were referred for protocol-guided, up-titration of HF medications. At each assessment we documented: HR, blood pressure, and HF medications including potential side effects. The primary objective was to identify the proportion of patients who had suboptimal HR control (HR ≥70 bpm) despite optimal conventional HF therapy.
From 172 patient records, 145 (84.3%)could tolerate long-term beta blockade with 57 (33.1%) prescribed the maximum recommended dose. Overall, 101 patients were in sinus rhythm with 31/101 (30.7% having an ejection fraction ≤35% and a resting HR ≥70 bpm.
In conclusion, suboptimal HR control is evident in approximately one in three HF patients in sinus rhythm despite aggressive optimisation of beta blocker therapy. This cohort may benefit from additional HR control.
Introduction
Beta-adrenoceptor blocking drugs (beta blockers) are an established prognostic therapy for chronic heart failure (HF). Of the many proposed mechanisms mediating these favourable effects, that of heart rate (HR) control is gaining interest.
The Systolic Heart Failure Treatment with If Inhibitor Ivabradine Trial (SHIFT) reported that ivabradine significantly reduced a combined end point of cardiovascular death or HF hospitalisations in a relatively high-risk HF population with an elevated resting HR.
HR control, therefore, appears to be both a modifiable risk factor and a disease modifying variable in patients with impaired left ventricular (LV) function and HF. Current strategies to control the sinus rate in HF patients include beta blockers, however, up-titration of these drugs can be difficult with patients reporting side effects and/or hypotension.
We, therefore, conducted a retrospective analysis of our HF database to define the prescribing patterns of beta blockers and to identify the proportion of HF patients who may be suitable for additional HR control after optimisation of conventional medical therapy.