RESUMO
BACKGROUND: Peripheral vasodilation is the key factor in the development of hyperdynamic circulation, sodium retention and functional renal failure in patients with cirrhosis. Brachial artery flow-mediated dilation (FMD) after transient vascular occlusion is a non-invasive method to assess the shear stress-induced arterial vasodilation. AIMS: To evaluate FMD in cirrhotic patients with and without ascites and to assess the relationship between FMD and intrarenal resistances. METHODS: Flow-mediated dilation was determined in 32 cirrhotic patients (22 with ascites) and 12 healthy controls and correlated with the intrarenal resistive index (RI) assessed by Doppler exploration. RESULTS: Basal diameter of the brachial artery was similar in healthy controls and in cirrhotic patients, whereas FMD was significantly higher in patients with cirrhosis and ascites [29.5% (range 10.3-50%)] than in pre-ascitic patients [17.3% (range 2.4-48.5%)] and healthy control subjects [11.6% (range 5.1-17.8%)] (P<0.001). Intrarenal RI was significantly higher in patients with cirrhosis than in healthy subjects, and a direct relationship existed between FMD and intrarenal RI (r=0.66; P<0.00001). CONCLUSIONS: These findings in vivo demonstrate that cirrhotic patients with ascites have an enhanced shear stress-induced peripheral vasodilation, which is closely related to intrarenal vasoconstriction.
Assuntos
Artéria Braquial/fisiologia , Cirrose Hepática/fisiopatologia , Fluxo Sanguíneo Regional/fisiologia , Circulação Renal/fisiologia , Vasodilatação/fisiologia , Ascite/fisiopatologia , Pressão Sanguínea , Artéria Braquial/diagnóstico por imagem , Frequência Cardíaca , Humanos , Fluxometria por Laser-Doppler , Estatísticas não Paramétricas , UltrassonografiaRESUMO
BACKGROUND: Transjugular intrahepatic portosystemic shunt (TIPS) is a treatment for portal hypertension-related complications. Accurate prediction of the outcome of patients treated with TIPS is important, because some patients have very short survival. Diastolic dysfunction is frequently observed in patients with cirrhosis. AIM: To investigate whether or not diastolic dysfunction can predict the outcome after TIPS. METHODS: Echocardiography with Doppler exploration was performed before and 28 days after TIPS insertion in 32 patients with cirrhosis. Several echocardiographic measures, including the early maximal ventricular filling velocity/late filling velocity (E/A) ratio as indicative of diastolic function, as well as laboratory, clinical and demographic variables were evaluated as predictors of survival. RESULTS: Univariate analysis revealed that the presence of diastolic dysfunction observed 28 days after TIPS (E/A ratio =1) and baseline model of end-stage liver disease score were related to survival. Multivariate analysis identified diastolic dysfunction as an independent predictor of death (RR 8.9, 95% CI 1.9 to 41.5, p = 0.005). During the first year of follow-up, six out of 10 patients with an E/A ratio =1 died, whereas all 22 patients with E/A ratio >1 survived. CONCLUSIONS: Diastolic dysfunction estimated using E/A ratio is a promising predictor of death in patients with cirrhosis who are treated with TIPS.
Assuntos
Diástole , Cirrose Hepática/cirurgia , Derivação Portossistêmica Transjugular Intra-Hepática , Adulto , Idoso , Ecocardiografia Doppler , Métodos Epidemiológicos , Feminino , Humanos , Cirrose Hepática/complicações , Cirrose Hepática/fisiopatologia , Masculino , Pessoa de Meia-Idade , Período Pós-Operatório , Prognóstico , Resultado do Tratamento , Disfunção Ventricular Esquerda/diagnóstico por imagem , Disfunção Ventricular Esquerda/etiologiaRESUMO
The aim of this study was to evaluate the cardiac effects of transjugular intrahepatic portosystemic shunts (TIPS) in cirrhotic patients with different effective blood volume. Two-dimensional echocardiography was performed before and 7 and 28 days after TIPS insertion in 7 cirrhotic patients with PRA <4 ng/mL/h (group A, normal effective blood volume) and 15 with PRA >4 ng/mL/h (group B, reduced effective blood volume). Before TIPS, most cirrhotic patients showed diastolic dysfunction as indicated by reduced early maximal ventricular filling velocity (E)/late filling velocity (A) ratio. Patients of group B differed from patients of group A because of smaller left ventricular volumes and stroke volume, indicating central underfilling. After TIPS insertion, portal decompression was associated with a significant increase of cardiac output (CO) and a decrease of peripheral resistances. The most important changes were recorded in patients of group B, who showed a significant increase of both the end-diastolic left ventricular volumes and the E/A ratio and a significant decrease of PRA. In conclusion, these results show that the hemodynamic effects of TIPS differ according to the pre-TIPS effective blood volume. Furthermore, TIPS improves the diastolic cardiac function of cirrhotic patients with effective hypovolemia. This result is likely due to a TIPS-related improvement of the fullness of central blood volume.