An atrioventricular septal defect (AVSD) can be successfully repaired by a skilled surgeon—but what happens if things go wrong afterwards? In this video, from our Echo Masterclass: Adult Congenital Heart Disease course, we'll take you through the reasoning behind the surgical strategies used to repair an AVSD and show you what to look for on a post-operative echo, if you suspect a complication.
[00:00:00] Repair of atrial ventricular septal defect or AVSD is largely guided by the extent of the septal defect, the morphology of the atrioventricular valve, and the size of the ventricles. Surgery for partial AVSD will involve patching the atrial septal defect. Percutaneous septal occluders are not suitable for this type of atrial septal defect as there is no inferior rim for anchoring the device. The close proximity of the defect to the valves of the AV node
[00:00:30] is also not favorable to house a device. Repair of the left AV valve is also undertaken usually by stitching together the two most anterior leaflets to bicuspidize the left AV valve. In the image on the left, the echo bright area on the valve is a suture. This valve has already been repaired. The image on the right shows that the regurgitation remains in the same location as the repair. The extent of the regurgitation is better seen in a long-axis view in this patient. As well as leaking, sometimes these repaired
[00:01:00] valves might become stenotic due to scarring of the leaflets so this needs to be carefully checked. Repairing a complete AVSD requires a lot of handy work from the surgeon. There are a number of strategies used to repair this lesion. The approach is based on the anatomy and sometimes requires a complicated Fontan-type of repair. However, I will describe one popular method called the 2-patch repair technique. AVSD patch is cut to the right shape and size and is then saw onto the ventricular septum, taking care to avoid sutures too close to the AV
[00:01:30] node, then a pericardial ASD patch is cut to size and suited to the top of the VSD patch. At this point, the surgeon ensures there are no leaks anywhere, no residual atrial or ventricular septal defect nor leaking from either ventricle to either atrium. The left valve is then repaired suturing together the commissure and then finally the right AV valve is repaired if required. With that many sutures, there's quite a few things to look for on the postoperative echos. Just like in partial AVSD, there can be
[00:02:00] a residual atrial septal defect or left atrioventricular valve dysfunction. The arrow pointing to the echo bright area on the valve is denoting a suture. This valve has already been repaired but the color flow shows that the regurgitation remains in the same location as the repair. The extent of regurgitation is better seen in the long axis view on this patient. As well as leaking, sometimes these repaired valves might become stenotic due to the scarring of the leaflets so the forward flow needs to be carefully checked, but sometimes the jets can get very, very
[00:02:30] tricky. Here is a patient post-repair with a jet entering the right atrium. If this is tricuspid regurgitation then it suggests significant pulmonary hypotension. If this is not tricuspid regurgitation, then what is it? Where does it come from? And is it bad? Well, if there's pulmonary hypotension, there should be other signs, right? Yes, septal flattening and we could cross-check the pulmonary artery pressure by using the PR Doppler signal. These images don't really support a diagnosis of
[00:03:00] pulmonary hypotension. The septum looks to be in its normal position and it doesn't look like the right ventricle is very dilated. So if that signal isn't tricuspid regurgitation, what is it? If we look at the origin of the jet, it's actually coming from the left ventricle into the right atrium. It is the left AV valve regurgitation which crosses the residual atrial septal defect that explains the high velocity and the systolic timing. It's very important to look carefully at the origin of the jets in these patients because the high velocity
[00:03:30] could easily be misdiagnosed as pulmonary hypotension. Heart block is common in these patients, so keep an eye out for that too. All that surgical origami involved in a complete atrioventricular septal defect repair means the potential for unusual residual jets is high, but with echo superpowers, we can establish if these are concerning or not. It is important to check the area of patch repairs at the atrial septum and ventricular septum. Check the function of the atrioventricular valves and finally, assess the elongated left ventricular outflow jet. It should remain
[00:04:00] widely patent.