Presentation
Pre AF ablation
Patient Data
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A linear filling defect is present in the left atrium, running between the left lateral wall anterior to the left inferior pulmonary vein ostium and the right anterior wall. This is consistent with cor triatriatum with a large inferior fenestration. All 4 pulmonary veins drain into the posterior chamber of the partially septated LA. The left atrial appendage is in the anterior chamber of the partially septated LA.
Case Discussion
Cor triatriatum is thought to result from failure of the common pulmonary vein to become fully incorporated into the left atrium during foetal development. Presentation depends on the fenestration size. In this case, it was an incidental finding in the work up for AF ablation. This is however an important finding for the cardiologists to be aware of when planning and performing catheter ablation for AF.