Cardiovascular adaptation to the Fontan circulation

Abstract

Although medium-term survival following Fontan operations in the modern era has improved dramatically, late cardiovascular and extracardiac morbidity are common and are associated with impaired quality of life and premature late mortality. This serves as a reminder of the extraordinary adaptations required of the cardiovascular system when the systemic arterial, systemic venous and pulmonary circulations are placed in series coupled to a single ventricular pump. This article reviews the key features and principles that govern interactions between the ventricle, systemic arterial circulation, the systemic venous and pulmonary circulatory compartments, the microcirculation, and lymphatic circulations. The overarching aim is to provide insight into the integrative pathophysiology that governs the Fontan circulation and stimulate thoughtful approaches to advance research.

Serial cardiovascular magnetic resonance feature tracking indicates early worsening of cardiac function in Fontan patients

“…The architecture of functionally univentricular hearts differs from that of morphologically normal hearts [27]. Their myocardium seems to be inherently more fibrotic than that of normal hearts [28].…”

Impaired lung function in children and adolescents with Fontan circulation may improve after endurance training

“…Many factors affect the development, including reduced blood flow, desaturation, collateral flow, lack of pulsatile flow, and absence of high blood flow and pressure during exercise. Also, the pulmonary circulation may have a progressive worsening over time leading to increased pulmonary vasculature resistance and, thus, a failing Fontan circulation (10,13,17,18).…”

Model-Based Indices of Early-Stage Cardiovascular Failure and Its Therapeutic Management in Fontan Patients

“…SVR and PVR), we could see that SVR was the main contributor to the effect, while there was only a relatively small change in PVR. This could reflect a vascular maladaptation of the systemic circulation to the chronic high systemic venous pressures [11] -the result of the circulations coupled in series.…”

“…While PVR is only a relatively small component of TVR, clinical and experimental studies have shown that it might have a large impact on cardiac output in the Fontan circulation [11]. This has formed the rationale behind PVD treatment.…”