Serial cardiopulmonary exercise testing in an asymptomatic young female receiving percutaneous balloon dilatation for cor triatriatum sinistrum at an early age

A young female was diagnosed as classic cor triatriatum sinistrum (CTS) at 38 months old incidentally and she received percutaneous catheter-based balloon dilatation twice at 41 and 48 months old. She took regular follow-up by echocardiography biannually with no re-stenosis of the orifice in the membrane between two chambers in the left atrium and she denied any cardiac-related symptoms. Serial cardiopulmonary exercise testing (CPET) by treadmill under Ramped-Bruce protocol was done at her 13, 19, and 23-year old. She could reach maximal effort and complete the three CPETs. No significant change of metabolic equivalent at anaerobic (MET) threshold, peak MET, and pulmonary function were noted in the serial CPETs and all of them were within normal limits comparing to the reference values of Chinese specific to her age. Our case report demonstrated that the concept of percutaneous catheter-based balloon dilatation of obstructive membrane for classic CTS without other associated congenital heart diseases is sound and feasible. The prognosis is well without re-obstruction and the cardiopulmonary fitness after that could be maintain as healthy peers for up to 18 years.