Single-Ventricle Physiology

Abstract

Single-ventricle physiology occurs in patients with hypoplastic ventricular heart defects, either on the right or left, who have undergone stepwise palliation surgeries ending with the Fontan procedure. After Fontan completion, these patients are dependent on passive venous return to the pulmonary circulation. The implications of passive flow are potentially devastating to the patient. We discuss some of the basic changes to the patient’s experience after a Fontan procedure, as well as the common complications. We also touch on some of the emerging management strategies for the common complications.

Ablation of intra-atrial reentrant tachycardias in adults with congenital heart disease: islands, isthmuses, channels, and walls

“…This approach streamlined the returning blood flow and improved hemodynamics while decreasing adverse effects on the RA, however it still generated high pressures on the lateral wall, facilitating the creation of an arrhythmogenic substrate. The extracardiac approach was developed following the lateral tunnel, and in this procedure the routing conduit was moved from inside the atria to outside the heart itself, routing the IVC to the right pulmonary artery, which resolved the issues of increased pressure on the RA (and adverse sequelae), but by definition excludes catheter access to living atrial tissue [2,21,22] (Fig. 8, Supplemental Fig.…”

“…Although there are life-saving advantages to this approach, such as normal blood saturations, there are long-term physiologic adaptations that lead to adverse chronic conditions, such as systemic venous hypertension. In addition, these patients are almost completely dependent on heart rate and atrioventricular conduction to increase cardiac output, and they have very little hemodynamic reserve [2].…”

“…We have seen remarkable advances regarding the treatment of congenital heart disease (CHD) in the modern era. Advances in reparative surgeries and procedures have led the survival of 85% of patients, which has contributed to a growing cohort of adult CHD (ACHD) patients [1,2]. It is estimated that adults now comprise two-thirds of the CHD patient population [3], and nearly one in 150 young adults will have some form of CHD [1].…”

“…As the population of ACHD patients grows, clinicians encounter pathologies secondary to both the congenital defects and to the corrective procedures [2]. Among the most common causes of hospital presentations for these patients are cardiac arrhythmias [4].…”