Cor Triatriatum Sinister: A Patient, a Review, and Some Unique Findings

Cor triatriatum sinistrum: presentation of syncope and atrial tachycardia

“…In 1949, Loeffler classed CT into three subgroups depending on the size and number of openings within the fibrous membrane: group 1 (no opening), group 2 (one or more small openings) and group 3 (wide opening). Those patients falling in group 3 are more likely to develop no or few symptoms of the disease where the condition is diagnosed incidentally and are likely to survive beyond infancy into late adulthood 3 6 7. In this case, our patient falls into group 3 category.…”

“…It is not fully understood why patients with large fenestrations within the fibrous membrane become symptomatic as adults. Electronic and mechanical remodelling of the myocardial tissue occur and it is thought that calcification or fibrosis of the membrane's opening can contribute to narrowing, flow obstruction and atrial fibrillation, which can increase the risk of thromboembolic events 3 7 10…”

A 14-Year-Old Boy with Unusual Presentation of Respiratory Distress

“…Patients with a severely restrictive membrane can present as early as in the neonatal period with respiratory distress [8]. Common presenting symptoms include recurrent respiratory infections, tachypnea, and failure to thrive [9]. More rarely, as was the case in the 14-year-old boy described above, patients present with isolated wheezing as the sole symptom for cor triatriatum [10].…”

“…Clinical exam findings are variable, but auscultation may include a diastolic murmur or a prominent P2 component of the second heart sound if pulmonary hypertension is present [9]. In cases when the membrane is not restrictive, the physical exam is often normal [8].…”

“…It is a sensitive and specific test to identify the presence of the thin fibromuscular membrane bisecting the left atria (Figure 2) [7]. Doppler flow through the membrane is used to determine the degree of restriction (Figure 3) [9]. …”