Incomplete Atrioventricular Septal Defect in a Patient with New Onset Atrial Fibrillation

Abstract

A 60-year-old female presented with palpitations associated presyncope and increased shortness of breath on exertion (NYHA II) following a recent viral illness. Physical examination revealed heart rate 122 bpm with blood pressure 97/65 mmHg. ECG confirmed atrial fibrillation with rapid ventricular response and intermittent ventricular ectopics. Her past medical history included spontaneous pneumothorax 30 years prior, recurrent migraines and pernicious anaemia. She had two uncompleted pregnancies. Transthoracic and transoesophageal echocardiography (Fig. 1) showed incomplete atrioventricular (AV) septal defect with ostium primum atrial septal defect (ASD). There was a cleft anterior mitral valve leaflet with grade 2/4 mitral regurgitation. Coronary angiogram confirmed normal coronary arteries and significant left to right shunt. Brain MRI did not demonstrate evidence of previous cerebral emboli. The patient underwent elective repair of the AV canal defect and mitral valve repair. The cleft mitral valve leaflet was opposed to create a single leaflet and 34 mm Cosgrove annuloplasty band was placed. The ASD was closed with a bovine pericardial patch sutured along the anterior mitral valve annulus and secured to the interatrial septum. Atrial fibrillation cryoablation was performed together with left atrial appendectomy. Postoperatively, she remained pacemaker dependent and subsequently underwent dual chamber pacemaker implantation 4 days later. Late presentation congenital heart disease often occurs following the development of arrhythmia and heart failure symptoms. This case demonstrates the importance of evaluation for structural heart disease in patients with new onset atrial fibrillation.