Defining heart failure in adult congenital heart disease

As the adult congenital heart disease (ACHD) population expands and ages, the incidence and prevalence of heart failure will rise. This poses several challenges, all complicated by our nascent understanding of heart failure epidemiology, pathophysiology and management in adults with congenital heart disease. Current definitions extrapolated from acquired heart failure often disregard the unique pathophysiology of heart failure in adults with congenital heart disease. Others have suggested that congenital heart disease is the 'original heart failure syndrome' implying that all ACHD patients are destined to manifest heart failure. Neither the adoption of acquired heart failure definitions nor the belief that heart failure is the common ultimate manifestation of ACHD has advanced the care of ACHD patients. The absence of a comprehensive definition that focuses on common themes while recognizing the unique manifestations of heart failure in ACHD stifles research progress and has translated to a paucity of ACHD specific recommendations in existing heart failure guidelines. Since many ACHD heart failure patients do not meet standard definitions of heart failure their access to potentially beneficial interventions such as cardiac rehabilitation is restricted by payers and regulators taking a narrow view of acquired heart failure guidelines. ACHD heart failure definitions that can be applied in the clinical and research setting are needed to guide treatment, facilitate communication between specialists, determine the prevalence and incidence of heart failure in AHCD, and improve ACHD patients' access to heart failure treatments. The purpose of this review is to understand how heart failure has been considered and defined in the existing ACHD literature and to highlight the need for a definition of heart failure applicable to ACHD.