Ventricular function and cardiac reserve in contemporary Fontan patients

Area of Science:

• Cardiology
• Pediatric Cardiology
• Cardiac Surgery

Background:

• Total cavopulmonary connection (TCPC) is a standard surgical procedure for single ventricle hearts.
• Intra-atrial lateral tunnel (ILT) and extracardiac conduit (ECC) are current TCPC techniques.
• Assessing ventricular function post-TCPC is crucial for long-term outcomes.

Purpose of the Study:

• To evaluate ventricular function at rest and during stress in patients after TCPC.
• To compare ILT versus ECC techniques regarding ventricular performance.
• To analyze the impact of left ventricular (LV) versus right ventricular (RV) dominance on function.

Main Methods:

• Echocardiography and magnetic resonance imaging (MRI) were performed on 99 patients (mean age 12.5 years).
• Stress MRI with dobutamine was conducted in 69 patients.
• Ventricular volumes, ejection fraction (EF), cardiac index (CI), and Tei-index were assessed.

Main Results:

• Both ILT and ECC showed comparable resting MRI parameters.
• Dobutamine stress decreased end-diastolic volume (EDVi) in all patients.
• ECC patients exhibited higher CI and EF during stress compared to ILT.
• Patients with dominant RV showed impaired diastolic function and lower systolic function, including contractility.

Conclusions:

• Ventricular function is generally well-preserved in contemporary Fontan patients.
• ECC technique is associated with better hemodynamic response during dobutamine stress.
• Dominant RV physiology is linked to reduced systolic and diastolic ventricular function.