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Single left ventricle — Clinical Guidelines

Overview

Single ventricle physiology encompasses congenital heart defects where only one functional ventricle supports the circulation, often requiring staged surgical palliation to optimize blood flow and oxygenation.

Diagnosis

Cardiac Imaging: Cardiac MRI and echocardiography essential for assessing ventricular function, anatomy, and identifying specific defects like hypoplastic left heart syndrome or tricuspid atresia 1 5.

Pulmonary Vein Assessment: Cardiac MRI to detect left-sided pulmonary vein obstruction, characterized by anatomical relationships between the aorta and pulmonary veins 5.

Hemodynamic Monitoring: Continuous monitoring of oxygen saturation and blood pressure to evaluate systemic and pulmonary circulation dynamics 7.

Management

Surgical Staged Palliation: Includes Norwood, Bidirectional Glenn, and Fontan procedures tailored to patient anatomy and physiology 1 7 8.

Percutaneous Interventions: Use of Diabolo stent technique for adjusting systemic-to-pulmonary artery shunts to manage pulmonary overcirculation 4.

Device Occlusion: Percutaneous occlusion techniques for managing venous collaterals, such as using Amplatzer Vascular Plug for hepatocardiac collaterals 6.

Ventricular Assist Devices (VADs): VADs can reverse cellular senescence and improve myocardial function in failing single ventricles 2.

Special Populations

Pediatrics: Off-pump bidirectional Glenn shunt can be safely performed in young children with single ventricle physiology 7.

Comorbidities: Awareness of rare complications like Norwood aneurysm necessitates vigilant surveillance post-surgery 3.

Key Recommendations

Assess Ventricular Function and Hemodynamics Regularly: Utilize advanced imaging techniques like CMR to monitor longitudinal and radial function, especially post-Fontan 1. (Evidence: Moderate)

Consider Percutaneous Adjustments for Pulmonary Circulation: Employ techniques such as the Diabolo stent for managing pulmonary overcirculation in single ventricle patients 4. (Evidence: Weak)

Evaluate and Manage Venous Collaterals: Use percutaneous device occlusion methods to address significant venous collaterals impacting oxygenation 6. (Evidence: Weak)

Monitor for Rare Complications: Regular follow-up imaging is crucial to detect rare complications such as Norwood aneurysms in long-term survivors 3. (Evidence: Expert opinion)

References

1 Sjöberg P, Frieberg P, Alsafi Z, Liuba P, Arheden H. Completion of Fontan circulation does not affect the low longitudinal contribution to stroke volume in patients with single ventricles. American journal of physiology. Heart and circulatory physiology 2026. link 2 Li X, Turaga D, Zhao Y, Tsai CR, Li RG, Morikawa Y et al.. Ventricular assist device unloading reverses microvascular senescence in single ventricle disease. Nature cardiovascular research 2026. link 3 Aljohani OA, Hasan A, Byrne F, Lamberti J, Murthy R. Norwood Aneurysm: Report of a Rare Phenomenon. World journal for pediatric & congenital heart surgery 2023. link 4 Maschietto N, Baird C, Porras D. Percutaneous intraluminal downsizing of systemic-to-pulmonary artery shunts: a novel application of the Diabolo stent technique-Case series and description of the technique. Catheterization and cardiovascular interventions : official journal of the Society for Cardiac Angiography & Interventions 2020. link 5 Kotani Y, Zhu J, Grosse-Wortmann L, Honjo O, Coles JG, Van Arsdell GS et al.. Anatomical risk factors, surgical treatment, and clinical outcomes of left-sided pulmonary vein obstruction in single-ventricle patients. The Journal of thoracic and cardiovascular surgery 2015. link 6 Kuo JA. Percutaneous device occlusion of hepatocardiac venous collateral via left transhepatic access in a patient with heterotaxy syndrome following Fontan procedure. Catheterization and cardiovascular interventions : official journal of the Society for Cardiac Angiography & Interventions 2015. link 7 Kandakure PR, Dharmapuram AK, Kale SB, Babu V, Ramadoss N, Rao IM et al.. Venoatrial shunt-assisted cavopulmonary anastomosis. Asian cardiovascular & thoracic annals 2010. link 8 Caspi J, Pettitt TW, Ferguson TB, Stopa AR, Sandhu SK. Effects of controlled antegrade pulmonary blood flow on cardiac function after bidirectional cavopulmonary anastomosis. The Annals of thoracic surgery 2003. link01198-6) 9 Amin Z, Backer CL, Duffy CE, Mavroudis C. Does banding the pulmonary artery affect pulmonary valve function after the Damus-Kaye-Stansel operation?. The Annals of thoracic surgery 1998. link00608-0) 10 Aeba R, Katogi T, Takeuchi S, Kawada S. Long-term follow-up of surgical patients with single-ventricle physiology: prognostic anatomical determinants. Cardiovascular surgery (London, England) 1997. link

Single left ventricle