Right ventricular end-diastolic stiffness heralds right ventricular failure in monocrotaline-induced pulmonary hypertension

• Tipo: Artigo em Revista Científica Internacional
• Data: 2016

Autores

Alaa, M (Autor) Outra; Abdellatif, M (Autor) Outra; Tavares Silva, M (Autor) FMUP; Oliveira Pinto, J (Autor) FMUP; Lopes, L (Autor) Outra; Leite, S (Autor) FMUP; Leite-Moreira AF (Autor) FMUP; Andre P Lourenco (Autor) FMUP

Revista

Título: American Journal of Physiology - Heart and Circulatory Physiology

Vol. 311

ISSN: 0363-6135

Editora: American Physiological Society

Indexação

ISI Web of Knowledge - 16 Citações

Scopus - 16 Citações

Outras Informações

ID Authenticus: P-00M-B8D

DOI: 10.1152/ajpheart.00202.2016

Abstract (EN): Recent studies suggest right ventricular (RV) stiffness is important in pulmonary hypertension (PH) prognosis. Smaller stroke volume (SV) variation after a certain RV end-diastolic pressure (EDP) respiratory variation as assessed by spectral transfer function (STF) may identify RV stiffness. Our aim was to evaluate RV stiffness in monocrotaline (MCT)-induced PH progression and to validate STF gain between EDP and SV as marker of stiffness. Seven-week-old male Wistar rats randomly injected with 60 mg/kg MCT or vehicle were divided into three groups (n 12 each) according to cardiac index (CI): controls (Ctrl), preserved CI (MCT pCI), and reduced CI (MCT rCI). All underwent RV pressure-volume (PV) evaluation 24-34 days after MCT, under halogenate anesthesia and constant positive-pressure ventilation. End-diastolic stiffness (beta(i)), end-systolic elastance (Ees(i)), arterial elastance for indexed volumes (Ea(i)), and preload recruitable stroke work (PRSW) were obtained and beat-to-beat fluctuations during ventilation assessed by STF. Eai was the strongest determinant of CI, alongside beta(i) but not PRSW. MCT rCI showed impaired ventricular-vascular coupling (VVC) and higher beta(i), along with low end-diastolic pressure (EDP) and stroke volume index (SVi) STF gain, denoting impaired preload reserve. On multivariate analysis beta(i) and not Eesi correlated with EDP-SVi STF gain (P < 0.001). Receiver-operating characteristics (ROC) curve analysis of EDP-SVi STF gain showed an area under curve of 0.84 for beta(i) prediction (P = 0.002). Afterload, impaired VVC and RV stiffness are major players in RV failure. RV stiffness can be assessed by STF gain analysis of respiratory fluctuations between EDP and SVi, which may constitute a prognostic tool in PH.

Idioma: Inglês

Tipo (Avaliação Docente): Científica

Nº de páginas: 10