Blunted peripheral blood supply and underdeveloped skeletal muscle in Fontan patients: The impact on functional capacity. (15th November 2018)

• Record Type: Journal Article
• Authors: Turquetto, Aida Luiza Ribeiro; dos Santos, Marcelo Rodrigues; Sayegh, Ana Luiza Carrari; de Souza, Francis Ribeiro; Agostinho, Daniela Regina; de Oliveira, Patrícia Alves; dos Santos, Yarla Alves; Liberato, Gabriela; Binotto, Maria Angélica; Otaduy, Maria Concepcion Garcia; Negrão, Carlos Eduardo; Canêo, Luiz Fernando; Jatene, Fabio Biscegli; Jatene, Marcelo Biscegli
• Is Part Of: International journal of cardiology. Volume 271(2018)
• Page Start: 54
• Page End: 59
• Publication Date: 2018-11-15
• Subjects: Fontan procedure -- Skeletal muscle -- Muscle sympathetic nerve activity -- Forearm blood flow -- Functional capacity; Cardiology -- Periodicals; Electronic journals; 616.12
• DOI: 10.1016/j.ijcard.2018.05.096
• Languages: English
• ISSNs: 0167-5273

Abstract

Abstract: Background: Changes in circulatory physiology are common in Fontan patients due to suboptimal cardiac output, which may reduce the peripheral blood flow and impair the skeletal muscle. The objective of this study was to investigate the forearm blood flow (FBF), cross-sectional area (CSA) of the thigh and functional capacity in asymptomatic clinically stable patients undergoing Fontan surgery. Methods: Thirty Fontan patients and 27 healthy subjects underwent venous occlusion plethysmography, magnetic resonance imaging of the thigh musculature and maximal cardiopulmonary exercise testing. Muscle sympathetic nerve activity (MSNA), norepinephrine measures, cardiovascular magnetic resonance, handgrip strength and 6-minute walk test were also performed. Results: Fontan patients have blunted FBF (1.59 ± 0.33 vs 2.17 ± 0.52 mL/min/100 mL p < 0.001) and forearm vascular conductance (FVC) (1.69 ± 0.04 vs 2.34 ± 0.62 units p < 0.001), reduced CSA of the thigh (81.2 ± 18.6 vs 116.3 ± 26.4 cm 2 p < 0.001), lower peak VO2 (29.3 ± 6 vs 41.5 ± 9 mL/kg/min p < 0.001), walked distance (607 ± 60 vs 701 ± 58 m p < 0.001) and handgrip strength (21 ± 9 vs 30 ± 8 kgf p < 0.001). The MSNA (30 ± 4 vs 22 ± 3 bursts/min p < 0.001) and norepinephrine concentration [265 (236–344) vs 222 (147–262) pg/mL p = 0.006] were also higher in Fontan patients. Multivariate linear regression showed FVC (β = 0.653; CI = 0.102–1.205; p = 0.022) and stroke volume (β = 0.018; CI = 0.007–0.029; p = 0.002) to be independently associated with reduced CSA of the thigh adjusted for body mass index. The CSA of the thigh adjusted for body mass index (β = 5.283; CI = 2.254–8.312; p = 0.001) was independently associated with reduced peak VO2 . Conclusion: Patients with Fontan operation have underdeveloped skeletal muscle with reduced strength that is associated with suboptimal peripheral blood supply and diminished exercise capacity. Highlights: Adaptive mechanisms occur in Fontan circulation due to suboptimal cardiac output. Higher sympathetic nerve activity and plasmatic norepinephrine levels happen. The increased systemic vascular resistance reduces peripheral blood flow. Underdeveloped skeletal muscle is a negative consequence of these changes. Low muscular volume of the thigh influences their functional capacity.