History
A 61-year-old man with a history of Ebstein’s anomaly, which initially went to had repaired in 1997; he then underwent tricuspid valve replacement with a 35-mm bioprosthesis in 2001. The initial surgery also involved an intraoperative ablation of an accessory pathway and right atrial maze procedure. For recurrent paroxysmal atrial fibrillation, he underwent a successful pulmonary vein isolation procedure in 2004. The electrophysiologic study performed at that time revealed severe sinus node dysfunction, but he remained asymptomatic. It was also noted that the tricuspid valve prosthesis was implanted proximal (atrial) to the coronary sinus.
Comments
It is not uncommon for the bioprosthetic valve to be sewn on the atrial aspect of the coronary sinus in repair of Ebstein’s anomaly. This is performed to avoid injury to the compact atrioventricular node.
Current Medications
The patient takes aldactone, furosemide (Lasix), warfarin, losartan (Cozaar), atorvastin (Lipitor), and aspirin.
Current Symptoms
More frequent spells of presyncope continued, but no frank syncope occurred. The patient also described infrequent tingling of the face and arm.
Physical Examination
Comments
No clinical evidence of overt right heart failure or systemic desaturation was found.
Laboratory Data
Electrocardiogram
Findings
Electrocardiography revealed marked sinus bradycardia with right bundle branch block and a ventricular rate of 45 bpm (Figure 9-1). A sinus arrhythmia is present, in addition to a premature atrial complex.
FIGURE 9-1
Chest Radiograph
Findings
A chest radiograph revealed a normal-sized heart with a prominent right ventricular contour (Figure 9-2) and clear lung fields. A bioprosthetic valve ring was evident.
Exercise Testing
The exercise test was a maximal test and was negative for ischemia. His exercise capacity was poor (5.5 metabolic equivalents), with a hypotensive response to exercise. In addition, a limited heart rate response of 81 bpm (peak), with frequent premature atrial and ventricular contractions (PACs and PVCs), was noted.