# Biventricular Surgical Approach in Noonan Syndrome With Hypertrophic Obstructive Cardiomyopathy

**Authors:** Ryo Fujimoto, Shingo Hirao, Tatsuhiko Komiya

PMC · DOI: 10.1016/j.jaccas.2025.106047 · JACC Case Reports · 2025-11-25

## TL;DR

A 19-year-old with Noonan syndrome underwent a biventricular surgical approach to treat complex heart muscle thickening.

## Contribution

The paper introduces a biventricular surgical approach for challenging hypertrophic obstructive cardiomyopathy in Noonan syndrome.

## Key findings

- Biventricular outflow tract obstruction was successfully addressed using combined left and right ventriculotomy.
- The approach enabled removal of abnormal muscle not visible through the aortic valve.
- This method is recommended for complex hypertrophic obstructive cardiomyopathy cases.

## Abstract

Noonan syndrome is commonly associated with cardiac abnormalities such as pulmonary valve stenosis, hypertrophic cardiomyopathy, and atrial septal defect.

A 19-year-old woman who was diagnosed with Noonan syndrome at birth had been receiving medical treatment for hypertrophic cardiomyopathy. The patient developed symptomatic hypertrophic obstructive cardiomyopathy, characterized by biventricular outflow tract obstruction. Surgical intervention was performed, including atrial septal defect closure and myectomy through left and right ventriculotomy approaches.

A right ventriculotomy was performed to resect the parietal band, septal myocardium, and anterior wall muscle. This was followed by a left ventriculotomy, enabling an extended septal myectomy from the resection margin near the aortic valve down toward the apex. This approach allowed for the removal of abnormal muscle bundles that were not visible through the aortic valve.

When myectomy for hypertrophic obstructive cardiomyopathy is challenging, surgical access via both left and right ventriculotomy should be strongly considered.

## Linked entities

- **Diseases:** Noonan syndrome (MONDO:0018997), hypertrophic cardiomyopathy (MONDO:0005045), pulmonary valve stenosis (MONDO:0006936), atrial septal defect (MONDO:0006664)

## Full-text entities

- **Diseases:** Noonan Syndrome (MESH:D009634), pulmonary valve stenosis (MESH:D011666), biventricular outflow tract obstruction (MESH:D000092243), cardiac abnormalities (MESH:D018376), atrial septal defect (MESH:D006344), Hypertrophic Obstructive Cardiomyopathy (MESH:D002312)
- **Species:** Homo sapiens (human, species) [taxon 9606]

## Full text

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## Figures

5 figures with captions in the complete paper: https://tomesphere.com/paper/PMC12926071/full.md

## References

9 references — full list in the complete paper: https://tomesphere.com/paper/PMC12926071/full.md

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Source: https://tomesphere.com/paper/PMC12926071