| Full text | |
| Author(s): |
Jorge Lucas Teixeira-Fonseca
[1]
;
Julliane Vasconcelos Joviano-Santos
[2]
;
Fabiana da Silva Alcântara
[3]
;
Polyana Leal da Silva
[4]
;
Michael Ramon Lima Conceição
[5]
;
Danilo Roman-Campos
[6]
Total Authors: 6
|
| Affiliation: | [1] Universidade Federal de São Paulo - Brasil
[2] Faculdade de Ciências Médicas de Minas Gerais - Brasil
[3] Universidade Federal de São Paulo - Brasil
[4] Universidade Federal de São Paulo - Brasil
[5] Universidade Federal de São Paulo - Brasil
[6] Universidade Federal de São Paulo - Brasil
Total Affiliations: 6
|
| Document type: | Journal article |
| Source: | Arquivos Brasileiros de Cardiologia; v. 120, n. 10 2023-10-20. |
| Abstract | |
Abstract Background The high incidence of atrial arrhythmias in pulmonary hypertension (PH) might be associated with poor prognosis, and the left atrium (LA) may play a role in this. An important finding in PH studies is that LA remodeling is underestimated. Objective This study investigated LA morphology and mechanical function, as well as the susceptibility to develop arrhythmias in a monocrotaline-induced PH (MCT-PH) model. Methods Wistar rats aged 4 weeks received 50 mg/kg of MCT. Electrocardiography and histology analysis were performed to evaluate the establishment of the MCT-PH model. The tissue was mounted in an isolated organ bath to characterize the LA mechanical function Results Compared with the control group (CTRL), the MCT-PH model presented LA hypertrophy and changes in cardiac electrical activity, as evidenced by increased P wave duration, PR and QT interval in MCT-PH rats. In LA isolated from MCT-PH rats, no alteration in inotropism was observed; however, the time to peak contraction was delayed in the experimental MCT-PH group. Finally, there was no difference in arrhythmia susceptibility of LA from MCT-PH animals after the burst pacing protocol. Conclusion The morphofunctional remodeling of the LA did not lead to increased susceptibility to ex vivo arrhythmia after application of the burst pacing protocol. (AU) | |
| FAPESP's process: | 21/05584-7 - Assessment of acute and chronic toxicity of the heart and brain exposed to pesticides found in potable water in Brazil |
| Grantee: | Danilo Roman Campos |
| Support Opportunities: | Research Grants - Young Investigators Grants - Phase 2 |
| FAPESP's process: | 19/21304-4 - Arrhythmogenic mechanisms in right heart diseases |
| Grantee: | Danilo Roman Campos |
| Support Opportunities: | Regular Research Grants |