Bilateral sympathectomy improves postinfarction left ventricular remodeling and function

Autor(es)

Zanoni, Fernando Luiz ; Simas, Rafael ; da Silva, Raphael Grillo ; Breithaupt-Faloppa, Ana Cristina ; Coutinho e Silva, Raphael dos Santos ; Jatene, Fabio Biscegli ; Moreira, Luiz Felipe P.

• Tipo de documento: Artigo Científico
• Fonte: JOURNAL OF THORACIC AND CARDIOVASCULAR SURGERY; v. 153, n. 4, p. 855+, APR 2017.
• Citações Web of Science: 2

Resumo

Objectives: To evaluate the influence of bilateral or left sympathectomy on left ventricular remodeling and function after myocardial infarction in rats. Methods: Myocardial infarction was induced in rats by ligation of the left anterior descending coronary. Seven days later, rats were divided into 4 groups: the myocardial infarction, myocardial infarction with left sympathectomy, myocardial infarction with bilateral sympathectomy, and sham groups. After 8 weeks, left ventricular function was evaluated with the use of a pressure-volume conductance catheter under steady-state conditions and pharmacological stress. Infarct size and extracellular matrix fibrosis were evaluated, and cardiac matrix metalloproteinases and myocardial inflammatory markers were analyzed. Results: The myocardial infarction and left sympathectomy group had an increased end diastolic volume, whereas the bilateral sympathectomy group had a mean end-diastolic volume similar to that of the sham group (P <. 002). Significant reduction in ejection fraction was observed in the myocardial infarction and left sympathectomy group, whereas it was preserved after bilateral sympathectomy (P < .001). In response to dobutamine, left ventricular contractility increased in sham rats, rising stroke work, cardiac output, systolic volume, end-diastolic volume, ejection fraction, and dP/dt max. Only bilateral sympathectomy rats had significant increases in ejection fraction (P <. 001) with dobutamine. Fibrotic tissue and matrix metalloproteinase expression decreased in the bilateral sympathectomy group compared to that in the myocardial infarction group (P <. 001) and was associated with left ventricular wall thickness maintenance and better apoptotic markers in noninfarcted myocardium. Conclusions: Bilateral sympathectomy effectively attenuated left ventricular remodeling and preserved systolic function after myocardial infarction induction in rats. (AU)

• Processo FAPESP: 13/06130-3 - Efeitos da Denervação Simpática Sobre a Função e o Remodelamento Ventricular Pós-Infarto Agudo do Miocárdio em Ratos
• Beneficiário: Fernando Luiz Zanoni
• Modalidade de apoio: Bolsas no Brasil - Pós-Doutorado