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1.
Am J Physiol Gastrointest Liver Physiol ; 314(2): G275-G286, 2018 02 01.
Artículo en Inglés | MEDLINE | ID: mdl-29074483

RESUMEN

Transjugular intrahepatic portosystemic shunt (TIPS) alleviates portal hypertension and possibly increases central blood volume (CBV). Moreover, renal function often improves; however, its effects on cardiac function are unclear. The aims of our study were to examine the effects of TIPS on hemodynamics and renal and cardiac function in patients with cirrhosis. In 25 cirrhotic patients, we analyzed systemic, cardiac, and splanchnic hemodynamics by catheterization of the liver veins and right heart chambers before and 1 wk after TIPS. Additionally, we measured renal and cardiac markers and performed advanced echocardiography before, 1 wk after, and 4 mo after TIPS. CBV increased significantly after TIPS (+4.6%, P < 0.05). Cardiac output (CO) increased (+15.3%, P < 0.005) due to an increase in stroke volume (SV) (+11.1%, P < 0.005), whereas heart rate (HR) was initially unchanged. Cardiopulmonary pressures increased after TIPS, whereas copeptin, a marker of vasopressin, decreased (-18%, P < 0.005) and proatrial natriuretic peptide increased (+52%, P < 0.0005) 1 wk after TIPS and returned to baseline 4 mo after TIPS. Plasma neutrophil gelatinase-associated lipocalin, renin, aldosterone, and serum creatinine decreased after TIPS (-36%, P < 0.005; -65%, P < 0.05; -90%, P < 0.005; and -13%, P < 0.005, respectively). Echocardiography revealed subtle changes in cardiac function after TIPS, although these were within the normal range. TIPS increases CBV by increasing CO and SV, whereas HR is initially unaltered. These results indicate an inability to increase the heart rate in response to a hemodynamic challenge that only partially increases CBV after TIPS. These changes, however, are sufficient for improving renal function. NEW & NOTEWORTHY For the first time, we have combined advanced techniques to study the integrated effects of transjugular intrahepatic portosystemic shunt (TIPS) in cirrhosis. We showed that TIPS increases central blood volume (CBV) through improved cardiac inotropy. Advanced echocardiography demonstrated that myocardial function was unaffected by the dramatic increase in preload after TIPS. Finally, renal function improved due to the increase in CBV. Recognition of these physiological changes significantly contributes to our clinical understanding of TIPS.


Asunto(s)
Cardiomiopatías/fisiopatología , Corazón/fisiopatología , Hipertensión Portal/cirugía , Riñón/fisiopatología , Cirrosis Hepática/fisiopatología , Presión Portal , Derivación Portosistémica Intrahepática Transyugular , Anciano , Biomarcadores/sangre , Biomarcadores/orina , Volumen Sanguíneo , Gasto Cardíaco , Cardiomiopatías/diagnóstico por imagen , Cardiomiopatías/etiología , Ecocardiografía Doppler , Electrocardiografía , Femenino , Tasa de Filtración Glomerular , Corazón/diagnóstico por imagen , Frecuencia Cardíaca , Humanos , Hipertensión Portal/diagnóstico , Hipertensión Portal/etiología , Hipertensión Portal/fisiopatología , Cirrosis Hepática/complicaciones , Cirrosis Hepática/diagnóstico , Masculino , Persona de Mediana Edad , Natriuresis , Recuperación de la Función , Factores de Tiempo , Resultado del Tratamiento
2.
Am J Physiol Gastrointest Liver Physiol ; 299(3): G784-90, 2010 Sep.
Artículo en Inglés | MEDLINE | ID: mdl-20616307

RESUMEN

Patients with cirrhosis exhibit impaired regulation of the arterial blood pressure, reduced baroreflex sensitivity (BRS), and prolonged QT interval. In addition, a considerable number of patients have a pulmonary dysfunction with hypoxemia, impaired lung diffusing capacity (Dl(CO)), and presence of hepatopulmonary syndrome (HPS). BRS is reduced at exposure to chronic hypoxia such as during sojourn in high altitudes. In this study, we assessed the relation of BRS to pulmonary dysfunction and cardiovascular characteristics and the effects of hyperoxia. Forty-three patients with cirrhosis and 12 healthy matched controls underwent hemodynamic and pulmonary investigations. BRS was assessed by cross-spectral analysis of variabilities between blood pressure and heart rate time series. A 100% oxygen test was performed with the assessment of arterial oxygen tensions (Pa(O(2))) and alveolar-arterial oxygen gradient. Baseline BRS was significantly reduced in the cirrhotic patients compared with the controls (4.7 +/- 0.8 vs. 10.3 +/- 2.0 ms/mmHg; P < 0.001). The frequency-corrected QT interval was significantly prolonged in the cirrhotic patients (P < 0.05). There was no significant difference in BRS according to presence of HPS, Pa(O(2)), Dl(CO), or Child-Turcotte score, but BRS correlated with metabolic and hemodynamic characteristics. After 100% oxygen inhalation, BRS and the QT interval remained unchanged in the cirrhotic patients. In conclusion, BRS is significantly reduced in patients with cirrhosis compared with controls, but it is unrelated to the degree of pulmonary dysfunction and portal hypertension. Acute hyperoxia does not significantly revert the low BRS or the prolonged QT interval in cirrhosis.


Asunto(s)
Barorreflejo/fisiología , Hiperoxia , Cirrosis Hepática Alcohólica/complicaciones , Enfermedades Pulmonares/terapia , Oxígeno/uso terapéutico , Anciano , Aldosterona/sangre , Angiotensina II/metabolismo , Factor Natriurético Atrial/sangre , Estudios de Casos y Controles , Endotelina-1/sangre , Femenino , Humanos , Enfermedades Pulmonares/etiología , Masculino , Persona de Mediana Edad , Péptido Natriurético Encefálico/sangre , Norepinefrina/sangre , Renina/sangre
3.
Am J Physiol Heart Circ Physiol ; 292(6): H2966-72, 2007 Jun.
Artículo en Inglés | MEDLINE | ID: mdl-17293491

RESUMEN

In cirrhosis, arterial vasodilatation leads to central hypovolemia and activation of the sympathetic nervous and renin-angiotensin-aldosterone systems. As the liver disease and circulatory dysfunction may affect baroreflex sensitivity (BRS), we assessed BRS in a large group of patients with cirrhosis and in controls who were all supine and some after 60 degrees passive head-up and 30 degrees head-down tilting in relation to central hemodynamics and activity of the sympathetic nervous and renin-angiotensin-aldosterone systems. One-hundred and five patients (Child classes A/B/C: 21/55/29) and 25 (n=11 + 14) controls underwent a full hemodynamic investigation. BRS was assessed by cross-spectral analysis of variabilities between blood pressure and heart rate time series. The median BRS was significantly lower in the supine cirrhotic patients, 3.7 (range 0.3-30.7) ms/mmHg than in matched controls (n=11): 14.3 (6.1-23.6) ms/mmHg, P<0.001. A stepwise multiple-regression analysis revealed that serum sodium (P=0.044), heart rate (P=0.027), and central circulation time (P=0.034) independently correlated with BRS. Head-down tilting had no effects on BRS, but, after head-up tilting, BRS was similar in the patients (n=23) and controls (n=14). In conclusion, BRS is reduced in cirrhosis in the supine position and relates to various aspects of cardiovascular dysfunction, but no further reduction was observed in parallel with the amelioration of the hyperdynamic circulation after head-up tilting. The results indicate that liver dysfunction and compensatory mechanisms to vasodilatation may be involved in the low BRS, which may contribute to poor cardiovascular adaptation in cirrhosis.


Asunto(s)
Barorreflejo , Presión Sanguínea , Frecuencia Cardíaca , Cirrosis Hepática Alcohólica/fisiopatología , Sistema Renina-Angiotensina , Sistema Nervioso Simpático/fisiopatología , Vasodilatación , Aldosterona/sangre , Estudios de Casos y Controles , Femenino , Inclinación de Cabeza , Humanos , Cirrosis Hepática Alcohólica/sangre , Masculino , Persona de Mediana Edad , Norepinefrina/sangre , Análisis de Regresión , Renina/sangre , Índice de Severidad de la Enfermedad , Sodio/sangre , Posición Supina , Pruebas de Mesa Inclinada
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