AMA Category 1 Credit for Physicians Only.
ASRT CME is not available.
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The patient had a LIMA -> LAD
SVG -> Ramus
SVG -> PDA
The TEE showed a PFO defect that was 0.626 cm in diameter in one view and about 0.5 cm diameter in a perpendicular view. The VTI of the PFO was 28.8 cm with flow from left-to-right of about 9 mls per cardiac cycle. The PFO was oval. A small Pericardial Effusion was present. Stomach Ridges, RVE, Calcified AMVL/Chordae Tendinae at P3 and Distal Anterior HK with Mild MR, Trace TR and an interatrial septal aneursym (IASA) with LAP and RAP about the same.
There are three questions on this case. What factors indicate that a PFO should be closed? What are the factors determining if a PFO can be closed with a device? Should the surgeon close the PFO? Does 3D echocardiography help in this decision compared to 2D echocardiography alone?
PFO can remain asymptomatic throughout the life of a patient. However, PFOs have been associated/implicated in paradoxical embolism of thrombus, fat, air, or even desaturated blood which can lead to cerebral ischemia, TIAs, stroke, infections, migraine headaches, and the platpnoea-orthodexia syndrome (rare syndrome of postural hypoxaemia accompanied by breathlessness). With respect to migraines, a right-to-left shunt is associated with the aura and migraine headaches.
zA PFO occurs in about 27% of patients and while the prevalence decreases with each decade of life, the size increases with each decade of life from 0.34 cm to 0.58 cm from the first to the 10th decade of life.
A PFO is associated with Chiari networks and interatrial septal aneurysms (IASA).
A PFO is the one factor associated with cryptogenic (idiopathic) ischemic stroke. A PFO with an IASA raises the risk of cryptogenic stroke. IASA alone has a lower risk than PFO alone. Warfarin therapy does not seem to decrease the risk of stroke over aspirin therapy. Percutaneous closure with a device may decrease the incidence of CVAs/TIAs but the devices may have incomplete closure and/or thrombus formation which increases the risk to about the risk of aspirin therapy alone. Of all of the devices the Amplatzer device had not thrombus formation in two studies but other devices had a higher incidence of thrombus formation. Surgical closure, while definitive, did not decrease the incidence of recurrent stroke better than the percutaneous closure devices. Recurrence of stroke after surgical closure was more common in older (> 45 yrs old) patients. Another study of surgical closure of a PFO showed excellent results with a double continuous closure technique for residual shunt and recurrent strokes (there were none).
For a device to work properly, mismatch of the device and the PFO must be minimized. 3D TEE has be instrumental in defining the anatomy, compared to 2D TEE, to prevent PFO-Device mismatch. Residual shunts are more likely with an IASA - but this may be because of the anatomy of the PFO. A typical PFO is located at the anterior and superior portion of the interatrial septum and is crescent shaped. A large eustachian valve, particularly if a Chiari network is present may increase the difficulty of the device deployment. Factors that increase the complexity of a percutaneous closure are:
This case was simply a judgement call because of the IASA with the PFO. Since the PFO was a single orifice that was small and oval and the Chiari Network was not extensive in that it did not extend to the interatiral septum, and that surgical closure results in older patients were not shown to be better than percutaneous closure of the PFO, we elected to not perform a surgical closure.
|Please answer the following questions correctly to obtain your CME.|
Three-dimensional imaging of the atrial septum and patent foramen ovale anatomy: defining the morphological phenotypes of patent foramen ovale
Patent Foramen Ovale: Anatomy, Outcomes, and Closure: Anatomy of a PFO
How should we assess patent foramen ovale?
Patent Foramen Ovale: Current Pathology, Pathophysiology, and Clinical Status