In May 2021, patient underwent a CABG x 4: saphenous vein to LAD, saphenous vein sequential graft to ramus and obtuse marginal, and saphenous vein to left ventricular branch of the right coronary artery. There were no noted complications and she was discharged home about 2 weeks later.
The patient continued to complain of intermittent chest pain, with 2 overnight admissions to a different hospital. Later that year, she presented to the ED at yet another hospital, and was found to have elevated troponins. She was diagnosed with an NSTEMI, and a cardiac cath showed:
“The sequential venous bypass graft to the intermediate artery and obtuse marginal artery was selectively engaged. It is ectatic and very large. The distal anastomotic site to the intermediate artery is patent. However, the sequential portion, it appears to be attached either to a coronary vein or to the coronary sinus. The whole markedly dilated coronary artery sinus was filled with contrast; draining into the right atrium…”
Subsequent CT angiography showed: “Her Ramus graft has a side to side anastomosis to the anterior cardiac vein, visible on CT. Graft dimensions are 5 mm at the site. It is anastomosed in an end to side fashion to a distal artery likely ramus. SVG limb to the LAD is also occluded."
Is this likely to be due to negligence during the CABG?
Files:
No questions yet!
Do you believe there might have been medical error?
Unless there are mitigating circumstances, prima facie there has been medical error here. There are techniques available to confirm that your bypass is going to an artery, including observing the thin wall of a vein compared to an artery; and, passing a probe proximally in the target vessel after opening it, which should confirm obstruction in an artery but find no obstruction in a vein.
Do you believe there might have been causation (i.e. the medical error resulted in an injury)?
On the admission where she presented with an STEMI, the clinical picture along with the CTA and angiogram show the surgical error. Although the complete report of these studies has not been included here, causation would be supported if there were no other findings on these studies suggesting a problem with one of the other grafts or coronaries.
What makes you a good expert for this case?
I am a seasoned cardiac surgeon with over 20 years experience in the field. I have performed over a 1,000 CABGs.
How often do you encounter cases similar to this one in your practice?
Rarely. I have seen it about 5 times in my entire career.
Do you believe there might have been medical error?
Multiple mistakes in this case. First: by standard of care, the left internal mammary artery (LIMA) is anastomosed to the left anterior descending artery (LAD). That gives the best long term prognosis since it remains patent for longer. It is the most important graft of all. In this case the surgeon used a vein for this bypass, erroneously. In fact, the vein graft to the LAD was already occluded (leading to another MI). Second: a coronary vein in the ramus distribution was confused with an artery. There are several ways to assess the nature of an epicardial vessel during bypass surgery. Most likely none of these have been considered. Not revascularizing the correct vessel (and even worse plugging a bypass graft to a vein instead!) not only doesn't provide benefit to the heart, but can also be harmful.
Do you believe there might have been causation (i.e. the medical error resulted in an injury)?
The bypass graft to the wrong coronary doesn't supply blood to the area of the heart that is underperfused. If the bypass goes to a vein, the situation is even worse because creates a V-A shunt with right sided overflow (leading to pulmonary hypertension). Also, this graft was sequential, so the jump graft to the obtuse marginal can also be compromised.
What makes you a good expert for this case?
I perform CABG on a daily basis. This is one of the most common procedures a heart surgeon performs. I work in a high volume coronary center in which I participate as primary or secondary operator to hundreds of cases\year.
How often do you encounter cases similar to this one in your practice?
I saw cases in which a bypass was performed on wrong ARTERIAL coronary vessel. I heard cases like the one reported above in other centers, but never happened in my Institution. This is a bad and silly mistake probably done by a non-experience surgeon.
Do you believe there might have been medical error?
This was a technical error on the part of the surgeon.
Do you believe there might have been causation (i.e. the medical error resulted in an injury)?
This created an A-V fistula in the heart, which can cause ischemia & heart failure.
What makes you a good expert for this case?
Knowledge & experience in cardiothoracic surgery
How often do you encounter cases similar to this one in your practice?
I have not seen this type of case previously
Do you believe there might have been medical error?
Without reviewing the file, it is not a definite yes, but it is extremely likely that the sequential saphenous vein graft was accidentally sewn/attached to a coronary vein instead of an artery. This seems to be well supported by both the coronary angiogram and the CTA. Coronary bypass grafts, when performed correctly, should be attached to coronary arteries and not veins.
Do you believe there might have been causation (i.e. the medical error resulted in an injury)?
This is more difficult to prove. Attaching the bypass graft to a vein should not lead to a NSTEMI/myocardial ischemia. However, not bypassing the intended target (coronary artery) will leave that artery with significant disease and narrowing and is thus prone to ischemia and heart attack/myocardial infarction.
What makes you a good expert for this case?
I have been in practice for 11 years at academic medical centers and am chief of my academic division currently. I have performed over 1300 heart surgeries in my career, the majority of which are CABG. I have reviewed legal cases in the past with excellent feedback from retaining attorneys.
How often do you encounter cases similar to this one in your practice?
This is a very rare complication that I have only heard about but have never seen.
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