Diastolic Heart Failure in Patients With the Fontan Circulation: A Review

Area of Science:

• Cardiology
• Congenital Heart Disease
• Pediatric Cardiac Surgery

Background:

• The Fontan circulation surgically connects vena cavae to pulmonary arteries for single-ventricle palliation.
• Fontan circulation failure can stem from mechanical issues, arrhythmias, pulmonary resistance, or ventricular decline.
• Systolic dysfunction is recognized, but diastolic dysfunction is an underappreciated cause of Fontan failure.

Purpose of the Study:

• To highlight the significance of diastolic ventricular dysfunction in Fontan circulation failure.
• To discuss the challenges and evolving methods for diagnosing diastolic dysfunction in single ventricles.
• To explore current and future therapeutic strategies for managing diastolic dysfunction in Fontan patients.

Main Methods:

• Review of existing literature on Fontan circulation physiology and failure modes.
• Discussion of diagnostic challenges for diastolic dysfunction in single-ventricle physiology.
• Exploration of potential diagnostic advancements combining biomarkers, imaging, and invasive data.

Main Results:

• Diastolic ventricular dysfunction is likely underdiagnosed in Fontan circulation.
• Current diagnostic techniques for biventricular hearts lack validation in single ventricles.
• Biomarkers, cardiac MRI, and echocardiography combined with pressure-volume data show promise for diagnosis.

Conclusions:

• Accurate, noninvasive diagnosis of diastolic dysfunction is critical for Fontan circulation management.
• Therapies for severe diastolic dysfunction are often limited, potentially necessitating advanced interventions like ventricular assist devices or transplantation.
• Improving Fontan palliation outcomes requires innovation in prevention and pharmacotherapy.