JOSE CLAUDIO MENEGHETTI
Projetos de Pesquisa
Unidades Organizacionais
Instituto do Coração, Hospital das Clínicas, Faculdade de Medicina
3 resultados
Resultados de Busca
Agora exibindo 1 - 3 de 3
- Myocardial blood flow assessment with (82)rubidium-PET imaging in patients with left bundle branch block(2015) FALCAO, Andrea; CHALELA, William; GIORGI, Maria Clementina; IMADA, Rodrigo; SOARES JR., Jose; VAL, Renata Do; OLIVEIRA, Marco Antonio; IZAKI, Marisa; KALIL FILHO, Roberto; MENEGHETTI, Jose C.OBJECTIVES: Perfusion abnormalities are frequently seen in Single Photon Emission Computed Tomography (SPECT) when a left bundle branch block is present. A few studies have shown decreased coronary flow reserve in the left anterior descending territory, regardless of the presence of coronary artery disease. OBJECTIVE: We sought to investigate rubidium-82 (Rb-82) positron emission tomography imaging in the assessment of myocardial blood flow and coronary flow reserve in patients with left bundle branch block. METHODS: Thirty-eight patients with left bundle branch block (GI), median age 63.5 years, 22 (58%) female, 12 with coronary artery disease (>= 70%; GI-A) and 26 with no evidence of significant coronary artery disease (GI-B), underwent rest-dipyridamole stress Rb-82-positron emission tomography with absolute quantitative flow measurements using Cedars-Sinai software (mL/min/g). The relative myocardial perfusion and left ventricular ejection fraction were assessed in 17 segments. These parameters were compared with those obtained from 30 patients with normal (82) Rb-positron emission tomography studies and without left bundle branch block (GII). RESULTS: Stress myocardial blood flow and coronary flow reserve were significantly lower in GI than in GII (p<0.05). The comparison of coronary flow reserve between GI-A and GI-B showed that it was different from the global coronary flow reserve (p<0.05) and the stress flow was significantly lower in the anterior than in the septal wall for both groups. Perfusion abnormalities were more prevalent in GI-A (p=0.06) and the left ventricular ejection fraction was not different between GI-A and GI-B, whereas it was lower in GI than in GII (p<0.001). CONCLUSION: The data confirm that patients with left bundle branch block had decreased myocardial blood flow and coronary flow reserve and coronary flow reserve assessed by Rb-82-positron emission tomography imaging may be useful in identifying coronary artery disease in patients with left bundle branch block.
- Calculation of Cardiac Kinetic Energy Index from PET images(2015) SIMS, John; OLIVEIRA, Marco Antonio; MENEGHETTI, Jose Claudio; GUTIERREZ, Marco AntonioCardiac function can be assessed from displacement measurements in imaging modalities from nuclear medicine Using positron emission tomography (PET) image sequences with Rubidium-82, we propose and estimate the total Kinetic Energy Index (KO) obtained from the velocity field, which was calculated using 3D optical flow(OF) methods applied over the temporal image sequence. However, it was found that the brightness of the image varied unexpectedly between frames, violating the constant brightness assumption of the OF method and causing large errors in estimating the velocity field. Therefore total brightness was equalized across image frames and the adjusted configuration tested with rest perfusion images acquired from individuals with normal (n=30) and low (n=33) cardiac function. For these images KEf was calculated as 0.5731 +/- 0.0899 and 0.3812 +/- 0.1146 for individuals with normal and low cardiac function respectively. The ability of KEf to properly classes patients into the two groups was tested with a ROC analysis, with area under the curve estimated as 0.906. To our knowledge this is the first time that KEf has been applied to PET images.
conferenceObject INFLUENCE OF LEFT BUNDLE BRANCH BLOCK IN ASSESSMENT OF MYOCARDIAL BLOOD FLOW FROM RUBIDIUM 82 POSITRON EMISSION TOMOGRAPHY IMAGING(2015) FALCAO, Andrea; CHALELA, William; GIORGI, Maria; IMADA, Rodrigo; SOARES JR., Jose; IZAKI, Marisa; KALIL-FILHO, Roberto; MENEGHETTI, Jose C.