Percutaneous mitral commisurotomy during pregnancy - A report of two cases performed in a United Kingdom tertiary centre and a review of the literature.

We report two cases of severe mitral stenosis where percutaneous mitral commisurotomy was performed within pregnancy. The first case involves an emergency procedure for a new diagnosis of severe mitral stenosis in a woman presenting with pulmonary oedema at 27 weeks' gestation. The second case is of a woman known to have mitral stenosis who underwent a semi-elective procedure for deterioration in symptoms. This procedure is not commonly performed in the United Kingdom because of low incidence of rheumatic heart disease. In addition, percutaneous mitral commisurotomy during pregnancy is rarely performed in the United Kingdom because of the improved healthcare system where majority of the women with moderate to severe mitral stenosis (even asymptomatic) will undergo planned interventions (percutaneous mitral commisurotomy or mitral valve surgery) before contemplating pregnancy. These cases highlight both the acute and chronic presentations of mitral stenosis and the impact pregnancy has on this condition. In addition, these cases show the importance of retaining skills in performing percutaneous mitral commisurotomy within our United Kingdom cardiologists.