Things have been very busy recently, and it's now more difficult for me to make time to craft lengthy, in-depth weekly posts, or get the OR time to put them together at all. This is a departure from eight or so months of (what I'd call, at least) consistent content, and I hate to be abandoning that. I'll be moving to a bi-monthly schedule proceeding into the winter--save for special announcements and things of that nature. However, there's no shortage of posts on this blog, so if you're new here, feel free to browse around!
Today's case was a redo mitral valve replacement. I'm not sure about the context, or why Dr. Nguyen decided to repeat the procedure, but the patient's condition must have been concerning enough to merit it. Having never seen a redo before, this case was interesting-- the fallout from the previous surgery was very visible. Still-recovering myocardial tissue showed blackened marks from the last case's cautery burns. I arrived before bypass, and progress was still being made to expose the aorta for the start of that procedure. I did a general overview of mitral replacements last post, so I thought it'd be fun to get into the true details of the surgery-- for example, bypass prep (e.g., cardioplegia use). To start on that, Dr. Nguyen usually uses retrograde cardioplegia instead of antegrade-- the difference being cannulation through the right-atrium-feeding coronary sinus, instead of the aortic root's coronary artery. Today was no outlier, and he went retrograde; this was done in hopes of maintaining certain heart conditions proceeding into the replacement. Retrograde delivery arrests the heart more slowly, and generally, antegrade is only safe for all patients (especially those suffering from aortic regurgitation) if administrated in tandem with retrograde. Myocardial damage can occur if it is used alone.
After bypass is wrapped up, the tissue surrounding the heart is held open with lengths of suture thread, pressed against the chest cavity, to make room to maneuver about the myocardium and secure an opening for the pump(s). Saline sprays and a vacuum are used to facilitate the removal of blood, and ensure a clear attachment from the pump to the opening.The draw pump tube, situated at the inferior vena cava's opening into the right atrium, is noticeably wider in diameter than the push pump at the aortic arch; I'm not sure why this is. I found a lot of good information about the more detail-heavy aspects of bypass on this website, so definitely take a look at that. It probably does a better overview of it than I have over the course of my many posts, and is all in one place to boot:
Today's case was a redo mitral valve replacement. I'm not sure about the context, or why Dr. Nguyen decided to repeat the procedure, but the patient's condition must have been concerning enough to merit it. Having never seen a redo before, this case was interesting-- the fallout from the previous surgery was very visible. Still-recovering myocardial tissue showed blackened marks from the last case's cautery burns. I arrived before bypass, and progress was still being made to expose the aorta for the start of that procedure. I did a general overview of mitral replacements last post, so I thought it'd be fun to get into the true details of the surgery-- for example, bypass prep (e.g., cardioplegia use). To start on that, Dr. Nguyen usually uses retrograde cardioplegia instead of antegrade-- the difference being cannulation through the right-atrium-feeding coronary sinus, instead of the aortic root's coronary artery. Today was no outlier, and he went retrograde; this was done in hopes of maintaining certain heart conditions proceeding into the replacement. Retrograde delivery arrests the heart more slowly, and generally, antegrade is only safe for all patients (especially those suffering from aortic regurgitation) if administrated in tandem with retrograde. Myocardial damage can occur if it is used alone.
After bypass is wrapped up, the tissue surrounding the heart is held open with lengths of suture thread, pressed against the chest cavity, to make room to maneuver about the myocardium and secure an opening for the pump(s). Saline sprays and a vacuum are used to facilitate the removal of blood, and ensure a clear attachment from the pump to the opening.The draw pump tube, situated at the inferior vena cava's opening into the right atrium, is noticeably wider in diameter than the push pump at the aortic arch; I'm not sure why this is. I found a lot of good information about the more detail-heavy aspects of bypass on this website, so definitely take a look at that. It probably does a better overview of it than I have over the course of my many posts, and is all in one place to boot:
Jumping further into the case, the mitral entrance Dr. Nguyen picked was...interesting. Three scoop-like metal supports, ringing the chest retractor and extending into the sternal incision, were used to hold the heart up and rotate it to the left in its cavity. This provides a very narrow pathway from under the right side of the heart to the mitral valve, and it's probably the most difficult-looking task I've seen in the OR (yet). Standard tools can't be used to remove the valve, simply because of how deep down it is-- the task calls for specialized elongated cutting instruments.
The next phase of the Heartwell Project is set up and ready to go, though I'm a bit tired of giving "soon, guys!" updates about it. Early November is our target launch window, and has been for a few weeks now. I might not talk about it until then.
The next phase of the Heartwell Project is set up and ready to go, though I'm a bit tired of giving "soon, guys!" updates about it. Early November is our target launch window, and has been for a few weeks now. I might not talk about it until then.
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