Left heart growth and biventricular repair after hybrid palliation.
Sojak V, Bokenkamp R, Kuipers I, Schneider A, Hazekamp M.
Interact Cardiovasc Thorac Surg. 2021 Feb 6:ivab004. doi: 10.1093/icvts/ivab004. Online ahead of print.
PMID: 33547474
Take Home Points:
- Hybrid procedure facilitates both Aortic valve/LVOT and LV growth regardless of the level of hypoplasia.
- Long-term follow up is required to see the benefit of pursuing the biventricular physiology in oppose to single ventricle physiology.
Commentary from Dr. Yasu Kotani (Okayama, Japan), section editor of Congenital Heart Surgery Journal Watch:
Summary:
A total of 33 infants with borderline LV (Borderline LV: N=19, Severe AS/LVOTO: N=14) underwent hybrid procedure at median age of 11days at 3.5kg. During the interstage period of 62 days, 7 catheter-based and 7 surgical-based reintervention were performed. Patients with borderline LV had a significant increase in both LVEDVi and AoV/LVOT. Similarly, patients with small AoV/LVOT achieved adequate growth of both LVEDVi and AoV/LVOT. Twenty-seven patients had a biventricular repair with 16 patients had aortic arch repair, ventricular septal defect closure, and relief of subaortic stenosis, 5 patients had Ross-Konno procedure, 5 patients had Yasui procedure, and 1 patient had AVSD and aortic arch repair. Twenty-three (85%) patients are alive at median follow up of 3.3 years. There were 22 reinterventions and 15 reoperations.
Significance:
Hybrid procedure has been developed as the first palliation of hypoplastic left heart syndrome but it is well known that this procedure can be fit to the patients with borderline LV in the aim for LV growth. This paper showed that 90% of patients with borderline LV achieved biventricular repair. More interestingly, it demonstrated that hybrid procedure can facilitate multi-level hypoplasia (AoV, LVOT, and LV) regardless of initial anatomy (either small AoV/LVOT or small LV volume).
Commentary:
Previous papers reported that hybrid procedure facilitated the LV growth and subsequently achieved biventricular repair which is no doubt. This paper from the one of the leading centers in Netherland also showed a high rate (90%) of the achievement of biventricular repair. They are quite aggressive that 5 out of 27 patients had Ross-Konno procedure to achieve biventricular repair. It is important to emphasize that 15 % died and 25% required reintervention after biventricular repair within relatively short-term period of 3 years.
This result makes us consider that the data should be carefully interpreted. Firstly, the paper did not describe the detail of the atrial communication which is very important. An exact size and how restrictive (pressure gradient between LA and RA) to adjust ASD are crucial to let the blood go into the LV, hence LV are under the circumstance to grow and this may alter the degree of the growth. Secondly, they showed a significant increase in AoV, LVOT, and LV volume, however, it seems some patients still fell from the criteria of biventricular size by looking at the figure. Although they describe the criteria, the final decision to go for the biventricular repair might be taken intraoperatively by surgeon, hence the selection bias may be existing. Finally, this study did not have the control group that single ventricle repair being performed. Taken together, long-term follow up is necessary to see the advantage of biventricular repair, including survival, freedom from reoperation, and functional status compared to single ventricle repair.