Regional Myocardial Perfusion Disturbance in Experimental Chronic Chagas Cardiomyopathy

Autor(es):Mostrar menos -

Lemos de Oliveira, Luciano Fonseca ^[1] ; Thackeray, James T. ^[2] ; Marin Neto, Jose Antonio ^[1] ; Dias Romano, Minna Moreira ^[1] ; Vieira de Carvalho, Eduardo Elias ^[1] ; Mejia, Jorge ^[3] ; Tanaka, Denise Mayumi ^[1] ; da Silva, Grace Kelly ^[1] ; Abdalla, Douglas Reis ^[4] ; Malamut, Carlos ^[5] ; Bengel, Frank M. ^[2] ; Higuchi, Maria de Lourdes ^[6] ; Schmidt, Andre ^[1] ; Cunha-Neto, Edecio ^[6] ; Simoes, Marcus Vinicius ^[1]

Afiliação do(s) autor(es)

^[1] Univ Sao Paulo, Med Sch Ribeirao Preto, 3900 Bandeirantes Ave, BR-14048900 Ribeirao Preto, SP - Brazil

^[2] Hannover Med Sch, Dept Nucl Med, Hannover - Germany

^[3] Hosp Israelita Albert Einstein, Sao Paulo - Brazil

^[4] Fac Human Talent, Hlth Dept, Uberaba - Brazil

^[5] Natl Commiss Nucl Energy CNEN, Nucl Technol Dev Ctr CDTN, Belo Horizonte, MG - Brazil

^[6] Univ Sao Paulo, Med Sch Sao Paulo, Heart Inst InCor, Sao Paulo - Brazil

• Tipo de documento: Artigo Científico
• Fonte: JOURNAL OF NUCLEAR MEDICINE; v. 59, n. 9, p. 1430-1436, SEP 1 2018.
• Citações Web of Science: 2

Resumo

Altered myocardial perfusion is a common finding in chronic Chagas cardiomyopathy (CCC), but its underlying histologic changes have not been elucidated. We investigated the occurrence of myocardial perfusion defects (MPDs) and the correlated regional changes to histology in an experimental model of CCC in hamsters. Methods: Female Syrian hamsters (n = 34) were infected with 3.5 x 10(4) to 10(5) trypomastigote forms of Trypanosoma cruzi, Y strain, and 6-10 mo afterward underwent in vivo imaging including resting Tc-99m-sestamibi SPECT, segmental and global left ventricular function assessment using 2-dimensional echocardiography, and F-18-FDG PET for evaluation of myocardial viability. Histologic analysis included quantification of fibrosis, inflammatory infiltration, and the diameter and density of myocardial microcirculation. Results: MPDs were present in 17 (50%) of the infected animals. Histologic analysis revealed no transmural scar in segments with an MPD, and normal or mildly reduced F-18-FDG uptake, indicating viable myocardium. Infected animals with an MPD, in comparison to infected animals without an MPD and control animals, showed a lower left ventricular ejection fraction (P = 0.012), a higher wall motion score index (P = 0.004), and a higher extent of inflammatory infiltration (P = 0.018) but a similar extent of fibrosis (P = 0.15) and similar microvascular diameter and density (P > 0.05). Segments with an MPD (n = 65), as compared with normally perfused regions in the same animal (n = 156), showed a higher wall motion score index (P = 0.005) but a similar extent of inflammatory infiltration, a similar extent of fibrosis, and a similar microvascular diameter and density. Conclusion: Resting MPDs are frequent in experimental CCC and are associated with myocardial inflammation but do not designate scar tissue, corresponding to regions with metabolically viable myocardium. (AU)

• Processo FAPESP: 11/03261-4 - Estudo das alterações da inervação simpática cardíaca e da perfusão miocárdica e sua correlação com a progressão da disfunção ventricular esquerda em modelo experimental de cardiomiopatia chagásica crônica no hamster
• Beneficiário: Marcus Vinicius Simões
• Modalidade de apoio: Auxílio à Pesquisa - Regular
• Processo FAPESP: 15/25209-5 - Emprego de métodos de imagem de alta-resolução in vivo para estudo das alterações perfusionais e inflamatórias miocárdicas em modelo experimental de cardiomiopatia chagásica crônica no hamster
• Beneficiário: Luciano Fonseca Lemos de Oliveira
• Modalidade de apoio: Bolsas no Brasil - Doutorado