Cabrelle G, Castaldi B, Vedovelli L, Gregori D, Vida VL, Padalino MA.
Eur J Cardiothorac Surg. 2021 Jan 4;59(1):244-252. doi: 10.1093/ejcts/ezaa289.
Take Home Points:
- Long-term (median 13 years) results in patients with a single RV and a 1 ½ ventricle repair are good in this relatively small group.
- There was no significant difference in survival or freedom from adverse events between simple and complex patients.
- When planned, a 1.5V repair may be beneficial in a very specific subset of patients and possibly lead to better outcomes than single ventricle (Fontan) palliation?
Commentary from Dr. Jared Hershenson (Greater Washington DC), section editor of Pediatric Cardiology Journal Watch: One and a half ventricle (1 ½ V) repair has been proposed for those with borderline/small right ventricles with hypothetical advantages over single ventricle palliation/Fontan such as ability to increase cardiac output and adapt to exercise, maintain pulsatile pulmonary blood flow, and low venous pressure in the IVC. This single center study retrospectively evaluated 29 patients who underwent 1 ½ V staged or primary repair between 1994-2018. Inclusion criteria were hypoplastic tricuspid valve (z-score < -3) and hypoplastic RV (< 2/3 predicted normal volume). Patients were divided into simple (CHD confined to right heart lesions) and complex anatomy (including other than right heart lesions and more challenging surgical repair). Echo data, cath data (PVR), and metabolic stress test data were followed. See table 2.
Median follow up was 12.5 years. Specific surgical details were discussed in the results section. Most common post-operative complications included pericardial and pleural effusions and arrhythmias. There were 3 late deaths with 2 considered non-cardiac related. 6 required a cardiac cath after a median time of 2.8 years, most commonly to address branch pulmonary artery stenosis. 3 patients required subsequent re-operation; 1 underwent transplant and the other 2 underwent biventricular conversion due to interval RV growth. Survival at 25 years was 89%; all had normal kidney and liver function (based on lab tests). Median O2 sat was 98%. Freedom from any late adverse event was 57% (16/28) and freedom from reoperation or re-intervention was 82.1% (23/28) and 78.6% (22/28) respectively. The complex patients had a much more significant initial post-operative course as would be expected. None of the “late” deaths occurred in the first year of follow up. 5 patients had neurological AEs which possibly contributed the most to the late AE rate, but the paper does not define this well. See tables 3 and 4. Comparison between the complex and simple group found no significant differences in survival, freedom from AE, or freedom from reintervention. See figure 1. Only 10 patients had MRIs and only 12 patients had metabolic stress testing. Mean VO2 was higher than compared to a control group of Fontan patients (33 +/- 5 vs. 24 +/- 1.6 ml/kg/min).
This surgical center planned for 1.5V repair after birth and show overall good results, with a few patients even being able to undergo biventricular conversion. No patients had PLE or chronic liver congestion, known complications of the Fontan. Important limitations include low total number of patients, lack of MRI data, and limited stress test data. When planned, a 1.5V repair may be beneficial in a very specific subset of patients and possibly lead to better outcomes than single ventricle (Fontan) palliation.