Opportunistic screening for asymptomatic left ventricular dysfunction in type 2 diabetes mellitus

Correspondence to Dr Chun Ka Wong, Cardiology Division, Department of Medicine, The University of Hong Kong, Hong Kong, Hong Kong; [email protected]

Introduction

Heart failure (HF) is a cardiovascular disease epidemic affecting 26 million people worldwide.¹ The incidence and prevalence of HF appear to be on a rising trend, particularly in developing countries due to the rapidly ageing population and the high prevalence of cardiovascular risk factors. In Asian countries, the prevalence of HF reportedly ranges between 1.3% and 6.7%.² In China, there are 4.2 million people living with HF.^{3 4} Over the past few decades, advances in pharmacological therapy, including ACE inhibitors,^{5 6} angiotensin II receptor blockers, beta-adrenergic blockers,^7–9 mineralocorticoid receptor antagonists,^{10 11} ivabradine¹² and more recently sacubitril/valsartan,¹³ as well as various device therapies, have been shown in randomised controlled trials to significantly improve patient outcomes particularly in those with reduced left ventricular ejection fraction (LVEF). Nonetheless, due to the progressive nature of the condition, the prognosis of HF in the real-world practice remains poor. In a recent European study, the 1-year mortality rate in patients with newly diagnosed HF was as high as 16.4%¹⁴; likewise, the reported 1-year mortality in Asia ranged between 8.9% and 19.5%.^15–17 Therefore, prevention of HF has turned into the priority of HF management at the public health level.

Diabetes mellitus (DM) is a well-recognised risk factor of cardiovascular diseases and HF.¹⁸ Patients with DM have a twofold–fourfold higher risk of HF compared with those without,¹⁹ and up to 27.7% of patients with DM had concomitant HF.^20–24 In 2001, the American College of Cardiology (ACC) and the American Heart Association (AHA) introduced a new HF classification system, including individuals who have not had clinical HF but are at high risk of developing HF due to either concomitant comorbidities such as DM (stage A), or underlying cardiac structural abnormalities (stage B).²⁵ The initial intention to include these so-called patients with ‘pre-HF’ into the classification is merely to help healthcare providers with the early identification of patients who are at risk of developing HF. Recently, sodium–glucose cotransporter-2 (SGLT2) inhibitors have been shown in pivotal studies to substantially reduce hospitalisation of HF and/or cardiovascular mortality in patients...