# Dilated Coronary Sinus Causing Left Ventricular Inflow Obstruction: Decision on surgical intervention

## TL;DR

A 5-month-old infant with a dilated coronary sinus and heart defects was treated with careful surgical planning using non-invasive imaging, avoiding direct intervention.

## Contribution

Demonstrates the use of virtual dissection for surgical decision-making in complex congenital heart anomalies.

## Key findings

- Virtual dissection of CT data provided detailed anatomy comparable to conventional dissection.
- Avoiding direct coronary sinus intervention led to improved left ventricular filling and cardiac output.
- Non-invasive imaging supported successful surgical planning and positive post-operative outcomes.

## Abstract

Objectives: A significantly dilated coronary sinus causing left ventricular inflow obstruction presents a challenging dilemma during surgical repair of associated anomalies. We report a 5-month-old male infant was referred to a national heart centre in Muscat, Oman, in 2023 with a persistent left superior caval vein, dilated coronary sinus, partially anomalous pulmonary venous drainage and a large atrial septal defect, resulting in left ventricular inflow obstruction and low cardiac output. The dilated coronary sinus intensified a left-to-right shunt, leading to left ventricular underfilling and early heart failure symptoms. Although surgical correction was planned, direct intervention on the coronary sinus was deferred after intraoperative assessment, supported by virtual dissection of 2-dimensional computed tomography datasets. This non-invasive imaging provided detailed anatomical understanding, comparable to conventional dissection and guided the decision to leave the dilated coronary sinus untouched. Post-operative outcomes showed improved left ventricular filling and resolution of low cardiac output, supporting the chosen strategy. This case highlights the role of virtual dissection in complex surgical planning and decision-making.