Biology at the University of Virginia, where I'm Medical Director of Nuclear Cardiology, Echocardiography, and the Stress Laboratory. And I am going to show you a case applying pet myocardial viability imaging. Here are my disclosures. So Ms. G is a 53-year-old female. She has a history of hypertension, dyslipidemia, and type 2 diabetes mellitins. She has a past history of coronary artery disease and had a non-ST elevation MI in 2017, at which time she had a chronic total occlusion for her right coronary artery that was treated medically, as well as a drug-eluting stent to her left circumflex. She had another non-ST elevation MI in 2020 and had a drug-eluting stent placed to her proximal left anterior descending artery. She did well after that stent placement, but she was known to have a reduced left ventricular ejection fraction with segmental anterior involvement, noted on prior echocardiographic examinations. And she presented with shortness of breath with a prominent exertional component and noted that she had been participating in local 5K races and she was no longer able to do that. So she had pet myocardial perfusion imaging to assess her perfusion and ischemia, but also had FTG imaging added for viability assessment, given that she'd had the prior wall motion abnormality. So her relative perfusion can be seen on the left and the polar plots on the right. You can see that there is extensive perfusion defect here involving the anterior, interoceptal, infraoceptal, inferior walls. As we get out towards the base, even the infralateral wall. And these perfusion defects are severe. There's 20% plus left ventricular ischemia. Multiple coronary territories are involved. And you can tell that the myocardium appears dilated at stress compared to rest, consistent with transient ischemic dilation or TID. If you look at the polar plots on the right, you can see that the computer flagged the areas as I had described. And again, 20 plus left ventricular ischemia. So on gated functional assessment, you can see that there is actually a decrease in left ventricular ejection fraction from rest to stress. There was some involvement of the anterior, inceptal walls at rest. And then this becomes more prominent and also has more prominent inferior involvement at stress. And then you can, if you look on the right, you can see the FDG viability imaging. And so if you look at the bottom, you can see the perfusion. And this is N13 ammonia perfusion. And then if you look up top, you can see fairly prominent FDG uptake in the areas with reduced perfusion, particularly in the anterior and septal areas. And this is consistent with a mismatch defect, which is suggestive of viable myocardium in an area that otherwise has a significant perfusion defect. And so ultimately, Ms. G underwent invasive coronary angiography. You look at the invasive angiogram on the left, you can see that she has an occluded right coronary artery. And then to the left, you could see that there is a proximal LAD lesion as well as a long circumflex lesion. And this lesion had an FFR that was significant at 0.72. So she had a multivessel significant ischemic disease. So ultimately, she underwent coronary artery bypass grafting with placement of a lemma to her LAD and a vein graft to an obtuse marginal with an uncomplicated clinical course. She started aggressive optimal medical therapy and cardiac rehabilitation was initiated. And ultimately, she got back to running 5Ks. In conclusion, this case showcases the added value of FDG, particularly in the 40% to 60% tracer uptake range to help characterize presence of viability. If somebody had more significant perfusion defects, then it's less likely that there would be viability. And if they have good tracer uptake, then they tend to have intact viability. That relative microcoronary perfusion imaging is more accurate for non-primary lesion assessment than for SPECT. We were able to assess multiple coronary territories with the one test. There are multiple additional measures available on this study, including LVEF reserve, the decrease in function from rest to stress, the presence of transient ischemic dilation, and quantitating the percent LV ischemia to both predict prognosis and estimate or predict the response to therapy. And then it's also important to note that that is an excellent modality for patients with known or likely complex coronary artery disease. Thank you.

myocardial viability

coronary artery disease

FDG imaging

coronary bypass surgery

cardiac rehabilitation