Abstract 1935: Simplified Criteria for Determining Stroke Potential by TEE; Could it Portend an Earlier Septal Closure Strategy?
Introduction Multiple observations regarding the causality of PFO and stroke have been made, focusing on defining stroke likelihood based on age, risk factors, septal redundancy, PFO size and transmitted bubble counts.
Hypothesis We hypothesized that the anatomic relationship between the primum and secundum septum and morphologic features of the atrial septum are directly related to PFO presence.
Methods 100 consecutive patients referred for either TIA/CVA evaluation (Group 1) or all others (Group 2) underwent TEE. The septal morphology in those with and without PFO was defined by the septal ‘track’ formation. A track was defined as a clear passageway between the septum primum and secundum and classified as either Absent (obliterated or obscured fossa ovale by the adjacent septal tissue; Type A), Intermediate (<1cm long and 0.25 cm wide; Type B) or Present (>1cm long and 0.25cm wide; Type C).
Results In Group 1 (19 pts) 0 were Type A, 2 (11%) were Type B and 17 (89%) were Type C. Of these 9pts (47%) had a PFO: 0/9 Type A, 1/9 (11%) Type B, and 8/9 (89%) Type C. In Group 2 (81 pts) 53 (65%) were Type A, 24 (30%) were Type B, and 4 (5%) were Type C. Of these, only 5 pts (6%) had PFO’s: 0 Type A, 2/5 (40%) Type B, and 3/5 (60%) Type C. When excluding Group A (0 PFOs), the odds ratio of having a PFO in Group C vs. B was 5.7 (1.3–25). The presence of the septal track formation (Type C) was a stronger predictor of PFO formation and initial referral for TIA/CVA evaluation than was an atrial septal aneurysm(p<0.05). Larger, bidirectional shunts were predominantly, 7/8pts (88%), present in Type C pts in whom 6/8 (75%) were in Group 1 pts; odds ratio for bidirectional shunt in Group C vs. Group B was 12.5 (1.4–112).
Conclusions Atrial septum morphology defined by the presence of a long inner atrial track (>1cm long and 0.25cm wide; Type C septum) showed high predilection for:
highly associated with TIA/CVA pts
not typically present in those referred for other reasons and
predicted larger, bidirectional shunts.
The presence of a septal track between the septum primum and secundum appears to be a strong predictor of favorable morphology for PFO presence helping to prognosticate those in whom future stroke potential is high, potentially leading to earlier referral for prophylactic closure.