# Resection of hypertrophic papillary muscles and mitral valve replacement in a patient with midventricular hypertrophic obstructive cardiomyopathy – a new approach

## TL;DR

A new surgical approach is described for treating a rare heart condition by removing hypertrophic muscles and replacing the mitral valve, improving patient outcomes.

## Contribution

A novel surgical technique combining resection of hypertrophic papillary muscles and mitral valve replacement is introduced for midventricular HOCM.

## Key findings

- The surgical approach led to significant improvement in clinical symptoms from NYHA III-IV to NYHA 0-I.
- The technique avoided septal myectomy and its associated complications.
- Stable outcomes were maintained over a 24-month follow-up period.

## Abstract

Midventricular hypertrophic obstructive cardiomyopathy (HOCM) is characterized by hypertrophy of the interventricular septum (IVS) and - in rare cases - of the papillary muscles (PM), which subsequently can cause dynamic left ventricular outflow tract obstruction (LVOTO) and severe heart failure symptoms. We report on a rare case of a 44-year-old patient suffering from midventricular HOCM with hypertrophic anterolateral PM and an additional chorda between the PM and the IVS.

We describe a new surgical approach via right anterolateral thoracotomy in 3-dimensional (3D) video-assisted minimal-invasive technique with resection of hypertrophic PMs as well as the entire mitral valve-apparatus and valve replacement avoiding septal myectomy and potentially associated complications. After an uneventful procedure clinical symptoms improved from NYHA III-IV at baseline to NYHA 0-I postoperatively and remained stable over a follow-up period of 24 months. Therefore, the presented technique may be considered as a new and alternative approach in patients with hypertrophic PMs and hypertrophic IVS as subtype of midventricular HOCM.