Treatment of non-restrictive cor triatriatum sinister during concomitant cardiac surgery

Abstract

Abstract Background Cor triatriatum is a rare congenital heart disease representing the 0.4% of all congenital cardiac anomalies. To date, no specific genetic alteration has been associated to cor triatriatum. The left-sided presentation (cor triatriatum sinister (CTS)) generally consists in a fibromuscular membrane that divides the left atrium into two chambers, therefore generating a varying grade of flow obstruction depending on the shape, location, and membrane fenestration size. Cor triatriatum sinister can be isolated or associated to other congenital heart defects such as ostium secundum atrial septal defect, patent foramen ovale or abnormal pulmonary veins drainage. Case presentation Our case is a 63-year-old woman who was diagnosed with a non-restrictive membrane during a hospitalization for acute heart failure. In the following 6 months, she started to become symptomatic. However, the onset of symptoms was more likely related to mitral valve regurgitation worsening and previously unknown coronary artery disease, rather than to CTS. She underwent bi-atrial surgical ablation (Cox Maze IV procedure) for atrial fibrillation (AF), surgical resection of interatrial membrane with mitral annuloplasty, and myocardial revascularization. Conclusion The onset and severity of symptoms in patients with CTS mostly depend on membrane fenestration size, grade of stenosis generated and pulmonary veins drainage site. However, some cases may remain asymptomatic until adulthood; the degree of pulmonary hypertension and congestive heart failure is determined by the presence of additional cardiac anomalies and the fibromuscular membrane fenestration. In some cases, CTS may remain asymptomatic, thus the diagnosis can be incidental.