I. | Accessory atrial chamber receives all pulmonary veins and communicates with left atrium |
A. No other connections (classic cor triatriatum) | |
B. Other anomalous connections | |
1. To right atrium directly | |
2. With totally anomalous pulmonary venous connection | |
II. | Accessory atrial chamber receives all pulmonary veins and does not communicate with the left atrium |
A. Anomalous connection to right atrium directly (cardiac TAPVC with all pulmonary veins first draining to a venous confluence) | |
B. With totally anomalous pulmonary venous connection (supracardiac or infracardiac TAPVC) | |
III. | Subtotal cor triatriatum |
A. Accessory atrial chamber receives part of the pulmonary veins and connects to the left atrium | |
1. Remaining pulmonary veins connect normally | |
2. Remaining pulmonary veins connect anomalously (partial cor triatriatum with PAPVC) | |
B. Accessory atrial chamber receives part of the pulmonary veins and connects to the right atrium | |
1. Remaining pulmonary veins connect normally (PAPVC with anomalously connected pulmonary veins first draining to a venous confluence) | |
2. Remaining pulmonary veins connect anomalously (mixed TAPVC) |