TasELF and VicElf are studies of Early LV Dysfunction and atrial fibrillation running in Tasmanian and Victorian. These are an observational dataset (TasELF) and an RCT (VicELF) that seek to provide early diagnosis and treatment to prevent the progression of asymptomatic to symptomatic heart failure (HF).
Heart failure is a problem that is assuming epidemic proportions, especially among the elderly. Unfortunately, its clinical diagnosis is associated with late-stage disease, which has a poor prognosis and responds poorly to medical therapy. At present, there is no effective strategy for identifying and preventing HF, with the result that patients present late in the course of the disease where hospitalisation is inevitable and treatment responses are poor.
The efforts of our group over recent years have been directed towards the detection of patients with asymptomatic LV dysfunction, so-called Stage B heart failure. We have documented:
- The combination of a clinical score with 6 minute walk can be used to identify the majority of patients with abnormal myocardial function and likely to progress to HF (Yang, Am J Cardiol. 2016 Jun 15;117(12):1959-65).
- A new echo parameter of myocardial deformation (Global Longitudinal Strain, GLS) is robust – GLS is an automated and quantitative technique for the measurement of cardiac function from gray-scale images, implying that the test can be gathered by non-experts in the community (Negishi K, JACC-Imaging 2014; Negishi T, JACC-Imaging 2016 in press). In time, the process of miniaturisation and automation will put the test in the hands of general practitioners or nurses.
- The combination of GLS with echo assessment of diastolic dysfunction and LV hypertrophy represent a triad of features that should define SBHF (J Am Coll Cardiol. 2015 Jan 27;65(3):257-66)
- Asymptomatic patients at high clinical risk and with LV dysfunction progress to symptomatic HF at a rate of about 10% per year (Yang, Eur J HF 2016;18:1331).
The implications of the identification of subclinical HF for preventive treatment are not well defined. In TasELF, our most recent community-based study in Tasmania, patients who adhered to an increase of cardioprotective therapy showed less progression to symptoms than untreated patients. However, because of non-adherence, this study did not complete recruitment. We believe that the limiting feature may be concern about hypotension.
In early HF, we have documented improvement of cardiac function with spironolactone in metabolic syndrome (Kosmala, JACC Cardiovasc Imaging. 2011 Dec;4(12):1239-49), obesity (Heart. 2013 Mar;99(5):320-6) Concurrent with our interests in early HF, our group has also been active in trying to treat HF with preserved HF (HFpEF). We have recently documented spironolactone to improve exercise capacity in these patients, with minimal change in blood pressure (Kosmala, JACC 2016; J Am Coll Cardiol 2016;68:1823-1834).
The planned VicELF study will identify patients with SBHF in the community and use this information to guide an intervention program to try to prevent the progression of these patients to symptomatic HF. We anticipate that the prompt initiation of therapy in these patients that are recognised to have the earliest phase of HF, will result in improvement in their functional capacity, and arrest in the subsequent progression to HF.