Ischemia-guided vs routine non-culprit vessel angioplasty for patients with ST segment elevation myocardial infarction and multi-vessel disease: the IAEA SPECT STEMI trial.

BACKGROUND: In patients with multi-vessel disease presenting with ST elevation myocardial infarction (STEMI), the efficacy and safety of ischemia-guided, vs routine non-culprit vessel angioplasty has not been adequately studied. METHODS: We conducted an international, randomized, non-inferiority trial comparing ischemia-guided non-culprit vessel angioplasty to routine non-culprit vessel angioplasty, following primary PCI for STEMI. The primary outcome was the between-group difference in percent ischemic myocardium at follow-up stress MPI. All MPI images were processed and analyzed at a central core lab, blinded to treatment allocation. RESULTS: In all, 109 patients were enrolled from nine countries. In the ischemia-guided arm, 25/48 (47%) patients underwent non-culprit vessel PCI following stress MPI. In the routine non-culprit PCI arm, 43/56 (77%) patients underwent angioplasty (86% within 6 weeks of randomization). The median percentage of ischemic myocardium on follow-up imaging (mean 16.5 months) was low, and identical (2.9%) in both arms (difference 0.13%, 95%CI - 1.3%-1.6%, P < .0001; non-inferiority margin 5%). CONCLUSION: A strategy of ischemia-guided non-culprit PCI resulted in low ischemia burden, and was non-inferior to a strategy of routine non-culprit vessel PCI in reducing ischemia burden. Selective non-culprit PCI following STEMI offers the potential for cost-savings, and may be particularly relevant to low-resource settings. (CTRI/2018/08/015384).

Functional impact of coronary stenosis observed on coronary computed tomography angiography: Comparison with ¹³N-ammonia PET.

BACKGROUND AND AIMS: We undertook this study to evaluate the functional impact of coronary abnormalities in patients with suspected coronary artery disease (CAD) by means of integrated positron emission tomography (PET) and coronary computed tomography angiography (CCTA) scan obtained on a hybrid state-of-the-art PET/CT scanner. METHODS: We studied 29 consecutive, patients with a clinically suspected intermediate risk for CAD, using a hybrid PET/CT 64 slice scanner. During a single scanning session, CCTA was performed for coronary anatomy evaluation, and a rest/adenosine stress (13)N-ammonia PET was performed for myocardial perfusion assessment in 3D mode with CT attenuation correction. RESULTS: Twenty four (82.7%) patients had atherosclerosis detected by CCTA; 15 patients had significant (≥50%) coronary stenoses and all 15 patients showed ischemia by PET; moreover, 10/15 patients had a Summed Stress Score >12.20/24 and 83.3% patients with atherosclerosis detected by CCTA showed ischemia by PET. Two of five patients with normal coronary arteries showed ischemia by PET. CCTA agreement in positive identification of PET ischemia was 91% and agreement in ruling out ischemia was 43%; PET agreement in detecting CCTA atherosclerosis was 83%, and agreement in ruling it out was 60%. CONCLUSIONS: We found a strong relation between significant coronary stenosis identified by CCTA and ischemia by PET. However, in cases with low-grade stenosis, PET scan can assess the functional significance of atherosclerotic abnormalities.

[Endothelial function assessment by positron emission tomography in patients with hypercholesterolemia]. / Estudio de la función endotelial mediante tomografía por emisión de positrones en pacientes con hipercolesterolemia.

UNLABELLED: Hypercholesterolemia prompts to endothelial dysfunction (ED) and ED predisposes to atherogenesis. ED appears early in the course of atherogenesis and it is considered a coronary artery disease (CAD) marker. OBJECTIVES: To assess endothelial function (EF) using Positron Emission Tomography (PET) in asymptomatic patients with recent dyslipidemia diagnosis and without history of ischemic heart disease and previous hypolipemiant treatment. MATERIAL AND METHODS: Fourteen asymptomatic patients with recent dyslipidemia diagnosis (< 6 months) were studied by obtaining a lipid profile, blood glucose, and a three phase 13N-ammonia PET scan: rest, cold pressor test (CPT) and pharmacologic stress with adenosine. EF was assessed by calculating the coronary flow reserve (CFR), endothelial-dependant vasodilatation index (EDVI), and coronary blood flow increase percentage in CPT (% Delta CF). RESULTS: 79% of patients with dyslipidemia had ED and all their values were lower than those previously published as normal: rest coronary flow 0.44 +/- 0.12 vs 0.57 +/- 0.147 (p = 0.002), CPT coronary flow 0.57 +/- 0.17 vs 0.88 +/- 0.26 (p = 0.001), stress coronary flow 1.24 +/- 0.05 vs 1.81 +/- 0.35 (p = 0.005), EDVI 1.28 +/- 0.25 vs 1.53 +/- 0.24 (p 0.017), CRF 2.79 +/- 0.94 vs 3.15 +/- 0.48 (p 0.198) and % Delta CF 29.08 +/- 24.62% vs 53 +/- 24.60% (p 0.022). CONCLUSIONS: Asymptomatic patients in early stages of dyslipidemia showed a greater ED prevalence that was detected by 13N-ammonia PET scan.

[Multidetector computed tomography of coronary arteries: state of the art. Second part: clinical applications]. / Tomografía computada multidetector de arterias coronarias: estado del arte. Parte II: Aplicaciones clínicas.

At the beginning of the evaluation of Coronary Artery Disease (CAD), Coronary Multidetector Computed Tomography (MDCT) was exclusively used to detect calcified plaques in coronary arteries through the Calcium Score, whose value by itself is limited. Nowadays, thanks to the technological advancements, potential clinical applications, with this method, include detection of coronary arterial stenosis, assessment of coronary bridges, and evaluation of anomalous coronaries. The intraluminal coronary stent evaluation is not possible yet, but this might become possible with the new-generation scanners. At the moment, the published results seem to be promising, nonetheless, the enthusiasm generated by this method should be accompanied by adequate training, as well as by its validation and certification.

[A method designed for the assessment of myocardial metabolism in rats with 18F-FDG using small-animal-PET. Initial experience in Mexico]. / Modelo de estudio mediante microPET para la evaluación del metabolismo glucolítico en el miocardio de rata con 18F-FDG. Experiencia inicial en México.

PURPOSE: To standarize an acquisition protocol for the study of myocardial metabolism in adult rats. MATERIAL AND METHODS: Three Wistar adult male rats were studied in three different protocols: no fasting group, fasting group over a period of 12 hr before the study with only water provided ad libitum, and fasting group by the same time receiving an oral 50% glucose solution. Thirty-minute acquisition images were obtained with a micro-PET, thirty and sixty minutes after the administration of 370-555 MBq 18F-FDG. Comparative and visual analysis were performed by two experts in the field. RESULTS: Eigtheen studies were analyzed, six per group. The best images were those of the first group, especially those taken at 60 minutes after the 18F-FDG administration. CONCLUSION: It is possible to establish the non-fasting protocol for the assessment of myocardial metabolism to be used in the future for the myocardial viability evaluation in ischemic cardiopathy.

Tomografía computada multidetector de arterias coronarias: estado del arte. Parte II: Aplicaciones clínicas / Multidetector computed tomography of coronary arteries: state of the art. Second part: clinical applications

At the beginning of the evaluation of Coronary Artery Disease (CAD), Coronary Multidetector Computed Tomography (MDCT) was exclusively used to detect calcified plaques in coronary arteries through the Calcium Score, whose value by itself is limited. Nowadays, thanks to the technological advancements, potential clinical applications, with this method, include detection of coronary arterial stenosis, assessment of coronary bridges, and evaluation of anomalous coronaries. The intraluminal coronary stent evaluation is not possible yet, but this might become possible with the new-generation scanners. At the moment, the published results seem to be promising, nonetheless, the enthusiasm generated by this method should be accompanied by adequate training, as well as by its validation and certification.

Estudio de la función endotelial mediante tomografía por emisión de positrones en pacientes con hipercolesterolemia / Endothelial function assessment by positron emission tomography in patients with hypercholesterolemia

Hypercholesterolemia prompts to endothelial dysfunction (ED) and ED predisposes to atherogenesis. ED appears early in the course of atherogenesis and it is considered a coronary artery disease (CAD) marker. OBJECTIVES: To assess endothelial function (EF) using Positron Emission Tomography (PET) in asymptomatic patients with recent dyslipidemia diagnosis and without history of ischemic heart disease and previous hypolipemiant treatment. MATERIAL AND METHODS: Fourteen asymptomatic patients with recent dyslipidemia diagnosis (< 6 months) were studied by obtaining a lipid profile, blood glucose, and a three phase 13N-ammonia PET scan: rest, cold pressor test (CPT) and pharmacologic stress with adenosine. EF was assessed by calculating the coronary flow reserve (CFR), endothelial-dependant vasodilatation index (EDVI), and coronary blood flow increase percentage in CPT (% Delta CF). RESULTS: 79% of patients with dyslipidemia had ED and all their values were lower than those previously published as normal: rest coronary flow 0.44 +/- 0.12 vs 0.57 +/- 0.147 (p = 0.002), CPT coronary flow 0.57 +/- 0.17 vs 0.88 +/- 0.26 (p = 0.001), stress coronary flow 1.24 +/- 0.05 vs 1.81 +/- 0.35 (p = 0.005), EDVI 1.28 +/- 0.25 vs 1.53 +/- 0.24 (p 0.017), CRF 2.79 +/- 0.94 vs 3.15 +/- 0.48 (p 0.198) and % Delta CF 29.08 +/- 24.62% vs 53 +/- 24.60% (p 0.022). Conclusions: Asymptomatic patients in early stages of dyslipidemia showed a greater ED prevalence that was detected by 13N-ammonia PET scan.

Modelo de estudio mediante microPET para la evaluación del metabolismo glucolítico en el miocardio de rata con 18F-FDG. Experiencia inicial en México / A method designed for the assessment of myocardial metabolism in rats with 18F-FDG using small-animal-PET. Initial experience in Mexico

PURPOSE: To standarize an acquisition protocol for the study of myocardial metabolism in adult rats. MATERIAL AND METHODS: Three Wistar adult male rats were studied in three different protocols: no fasting group, fasting group over a period of 12 hr before the study with only water provided ad libitum, and fasting group by the same time receiving an oral 50% glucose solution. Thirty-minute acquisition images were obtained with a micro-PET, thirty and sixty minutes after the administration of 370-555 MBq 18F-FDG. Comparative and visual analysis were performed by two experts in the field. RESULTS: Eigtheen studies were analyzed, six per group. The best images were those of the first group, especially those taken at 60 minutes after the 18F-FDG administration. CONCLUSION: It is possible to establish the non-fasting protocol for the assessment of myocardial metabolism to be used in the future for the myocardial viability evaluation in ischemic cardiopathy.

Principios y aplicaciones de la tomografía por emisión de positrones (PET) en la cardiologÝa. PET en MÚxico: una realidad / Principles and applications of positron emission tomography (PET) in cardiology. PET in Mexico: a reality

Positron emission tomography (PET) offers the unique capability of measuring non-invasive by the regional myocardial substrate flow and the biochemical reaction index in millimol per minute per gram of myocardial tissue. PET also allows for the assessment or quantification of regional myocardial blood flow, cardiac metabolism, ventricular function, myocardial viability, as well as autonomous nervous system, research and evaluating of dilated myocardiopathy and of ventricular hypertrophy. PET's success is based on the radioisotopes properties, their very short half-life allows for the administration of large doses.