Systemic Atrioventricular Valve Replacement in Patients With Functional Single Ventricle

Area of Science:

• Cardiology
• Pediatric Cardiac Surgery
• Congenital Heart Disease

Background:

• Single ventricle physiology presents complex challenges in pediatric cardiac surgery.
• Atrioventricular valve (AVV) dysfunction is a common complication requiring intervention.
• Outcomes of AVV replacement in this high-risk population require further investigation.

Purpose of the Study:

• To review the outcomes of atrioventricular valve replacement in patients with single ventricle physiology.
• To identify risk factors associated with mortality and re-intervention after AVV replacement.
• To assess the impact of AVV replacement timing relative to other palliative surgical stages.

Main Methods:

• Retrospective review of 37 consecutive patients undergoing initial AVV replacement between 2001 and 2016.
• Actuarial survival and cumulative incidence of re-replacement were calculated.
• Multivariate analysis was performed to identify risk factors for mortality and re-replacement.

Main Results:

• Actuarial survival rates were 73%, 65%, and 59% at 1, 5, and 10 years, respectively.
• Significant risk factors for mortality included small body surface area, preoperative inotropic support, primary valve replacement, oversized prosthesis, and extracorporeal membrane oxygenation support.
• Cumulative incidences of re-replacement were 11%, 17%, and 17% at 1, 5, and 10 years, with no identified risk factors for re-intervention.

Conclusions:

• Atrioventricular valve replacement is a viable treatment option for select single ventricle patients.
• Outcomes are significantly poorer in smaller patients with impaired ventricular function, often necessitating oversized prostheses.
• Timing of AVV replacement in relation to bidirectional cavopulmonary shunt and Fontan completion impacts survival and further palliation success.