quantitative assessment of myocardial blood flow and extracellular volume fraction using 68 ga-dota-pet: a feasibility and validation study in large animals

Here we evaluated the feasibility of pet with gallium-68 (68ga)-labeled dota for non-invasive assessment of myocardial blood flow (mbf) and extracellular volume fraction (ecv) in a pig model of myocardial infarction. we also aimed to validate mbf measurements using microspheres as a gold standard in healthy pigs. 8 healthy pigs underwent three sequential 68ga-dota-pet/ct scans at rest and during pharmacological stress with simultaneous injection of fluorescent microspheres to validate mbf measurements. myocardial infarction was induced in 5 additional pigs, which underwent 68ga-dota-pet/ct examinations 7-days after reperfusion. dynamic pet images were reconstructed and fitted to obtain mbf and ecv parametric maps. mbf assessed with 68ga-dota-pet showed good correlation (y = 0.96x + 0.11, r = 0.91) with that measured with microspheres. mbf values obtained with 68ga-dota-pet in the infarcted area (lad, left anterior descendant) were significantly reduced in comparison to remote ones lcx (left circumflex artery, p < 0.0001) and rca (right coronary artery, p < 0.0001). ecv increased in the infarcted area (p < 0.0001). 68ga-dota-pet allowed non-invasive assessment of mbf and ecv in pigs with myocardial infarction and under rest-stress conditions. this technique could provide wide access to quantitative measurement of both mbf and ecv with pet imaging.