Body composition in patients with Fontan physiology: a systematic review

Abstract

Fontan circulation is a highly abnormal circulatory state that may affect various organ systems. The effect on body composition is an important factor to assess the condition of the patient. This systematic review assesses body composition and possibly related adverse outcomes in patients with a Fontan circulation, to provide an overview of current insights. Studies evaluating body composition by compartment (either fat mass or lean/muscle mass) in Fontan patients published up to April 2023 were included in this systematic review. Of 1392 potential studies, 18 studies met the inclusion criteria. In total, body composition measurements of 774 Fontan patients were included. Body composition was measured using dual-energy X-ray absorptiometry (DXA) (n = 12), bioelectrical impedance analysis (BIA) (n = 5), computer tomography (CT) (n = 1), or magnetic resonance imaging (MRI) (n = 1). All studies reported a normal body mass index (BMI) in Fontan patients, compared to controls. Five out of nine studies reported significantly higher body fat values, and twelve out of fifteen studies reported significantly lower muscle or lean mass values in the Fontan population compared to the healthy population. Unfavorable body composition in Fontan patients was associated with decreased exercise capacity, worse cardiac function, and adverse outcomes including hospital admissions and death. Conclusions: Despite having a normal BMI, Fontan patients have an increased fat mass and decreased muscle mass or lean mass compared to the healthy population. This unfavorable body composition was associated with various adverse outcomes, including a decreased exercise capacity and worse cardiac function. What is Known:• Patients with a Fontan circulation have a decreased exercise capacity compared to healthy peers, an unfavorable body composition might be a contributor to their impaired exercise capacity. What is New:• Fontan patients are predisposed to an unfavorable body composition, characterized by increased fat mass and decreased muscle mass accompanied by a normal BMI compared to the healthy population.• Among others, unfavorable body composition was associated with decreased exercise capacity, cardiac function, and increased morbidity in patients with a Fontan circulation.

Noninvasive Advanced Cardiovascular Magnetic Resonance–Derived Fontan Hemodynamics Are Associated With Reduced Kidney Function But Not Albuminuria

“…Furthermore, it has been suggested that creatinine‐based eGFR methods would overestimate mGFR in patients with a Fontan circulation because of its reliance on skeletal muscle mass, 28 , 29 which is known to be reduced in these patients. 32 Cystatin C–based methods have been proposed to circumvent this issue; however, the applicable equations designed for the pediatric and adolescent demographic only became available after our study's enrollment phase. 33 Consequently, these measurements were not available in our data sets.…”

Cardiovascular Imaging-Derived Skeletal Muscle Mass Correlates With Fitness and Survival in Patients With Univentricular Circulation

“…Low exercise tolerance and sarcopenia are major factors contributing to morbidity and quality of life in patients with total cavopulmonary connection (TCPC) [1][2][3]. Many macroscopic and metabolic changes in skeletal muscle are observed in patients with univentricular circulation.…”