Referral and access to heart function clinics: A realist review

Heart failure (HF) clinics are highly effective, yet not optimally utilized. A realist review was performed to identify contexts (eg, health system characteristics, clinic capacity, and siting) and underlying mechanisms (eg, referring provider knowledge of clinics and referral criteria, barriers in disadvantaged patients) that influence utilization (provider referral [ie, of all appropriate and no inappropriate patients] and access [ie, patient attends ≥1 visit]) of HF clinics.

Following an initial scoping search and field observation in a HF clinic, we developed an initial program theory in conjunction with our expert panel, which included patient partners. Then, a literature search of seven databases was searched from inception to December 2019, including Medline; Grey literature was also searched. Studies of any design or editorials were included; studies regarding access to cardiac rehabilitation, or a single specialist for example, were excluded. Two independent reviewers screened the abstracts, and then full-texts. Relevant data from included articles were used to refine the program theory.

A total of 29 papers from five countries (three regions) were included. There was limited information to support or refute many elements of our initial program theory (eg, referring provider knowledge/beliefs, clinic inclusion/exclusion criteria), but refinements were made (eg, specialized care provided in each clinic, lack of patient encouragement). Lack of capacity, geography, and funding arrangements were identified as contextual factors, explaining a range of mechanistic processes, including patient clinical characteristics and social determinants of health as well as clinic characteristics that help to explain inappropriate and low use of HF clinics (outcome).

Given the burden of HF and benefit of HF clinics, more research is needed to understand, and hence overcome sub-optimal use of HF clinics. In particular, an understanding from the perspective of referring providers is needed.