Acquired Fontan Physiology Secondary to Acute Mechanical Tricuspid Valve Failure in a Patient With Massive Right Heart Enlargement and Ebstein’s Anomaly

Abstract

A 25-year-old man with Ebstein’s anomaly and a secundum atrial septal defect had a mechanical tricuspid valve replacement (St. Jude 31-mm valve) and atrial septal defect closure when he was 15 years old. He was under long-term specialist follow-up and had recently been admitted with symptoms and signs of right heart failure secondary to new onset atrial flutter. He was direct-current cardioverted and commenced on ramipril and metoprolol. He then went to have an electrophysiological study and successful atrial flutter ablation. At review 6 months later he reported good exercise tolerance and was now able to play 18 holes of golf, whereas previously he could only manage 9 holes. However, he commented that since the electrophysiological procedure he had been unable to hear his prosthetic valve clicks. On clinical examination he was not cyanosed, the jugular venous pressure was elevated at 4 cm without prominent V waves, there was a soft first heart sound, no audible mechanical valve clicks, and a pansystolic murmur. There were no signs of heart failure or peripheral edema. An electrocardiogram demonstrated sinus rhythm, right axis deviation, first-degree heart block, and right bundle-branch block with QRS duration of 200 ms. Echocardiography and fluoroscopy (Figure 1) showed that the leaflets of the …