# Posterior aortoventricular enlargement of root and outflow tract: Early and mid-term results

## TL;DR

A new surgical technique for enlarging the left ventricular outflow tract and aortic annulus shows promising early and mid-term results in patients with congenital hypoplasia.

## Contribution

A novel posterior enlargement technique that avoids incisions in the septum and right ventricle is introduced and evaluated.

## Key findings

- The technique achieved 100% freedom from cardiac death and aortic valve or root reoperation at 10 years.
- LVOT gradient was significantly reduced from 50 mm Hg preoperatively to 9 mm Hg at discharge.
- LVOT and annular diameters increased significantly post-surgery and were maintained at follow-up.

## Abstract

Congenital hypoplasia of the left ventricular outflow tract (LVOT) and aortic annulus is a challenging problem. We have developed a novel posterior enlargement technique that avoids a septal and right ventricular incision while effectively enlarging the LVOT and aortic annulus. Here we report mid-term results with the use of this technique.

Between 2011 and 2023, 5 patients (3 males [60%]; mean age, 28 ± 23 years) underwent posterior aortoventricular enlargement. The aortic valve and root were replaced by an autograft (n = 4) or a stentless porcine prosthesis (n = 1).

There were cases of no early death, myocardial infarction, neurologic complications, or permanent pacemaker implantation. One patient died 3 years postoperatively in a traffic accident, and 1 patient required pulmonary conduit reoperation for infective endocarditis 6.5 years postoperatively. Freedom from cardiac death and aortic valve or root reoperation was 100% at 10 years. Two patients had AR 1 at discharge, and 3 patients had AR 1 at last follow-up, between 12.1 and 13.4 years postoperatively, including the 2 with AR 1 at discharge. Median LVOT diameter was 12 mm preoperatively (interquartile range [IQR], 9.5-12.6 mm), 20 mm (IQR, 20-21 mm) at discharge, and 20 mm (IQR, 20-21 mm) at last follow-up. Median annular diameter was 17 mm (IQR, 15-18 mm) preoperatively, 21 mm (IQR, 20-22 mm) at discharge, and 25 mm (IQR, 24-26 mm) at last follow-up. Median LVOT gradient was reduced from 50 mm Hg (IQR 41-57 mm Hg) preoperatively to 9 mm Hg (IQR, 7-16 mm Hg) at discharge. All patients remained in sinus rhythm with normal PR intervals and QRS complexes.

Posterior aortoventricular enlargement combined with root replacement yields effective relief of LVOT and annular hypoplasia. It appears to be a durable option for younger and older patients alike.