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Kalluru R, Gadde S, Chikatimalla R, Dasaradhan T, Koneti J, Cherukuri SP. Cirrhotic Cardiomyopathy: The Interplay Between Liver and Heart. Cureus 2022; 14:e27969. [PMID: 36120195 PMCID: PMC9467492 DOI: 10.7759/cureus.27969] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Accepted: 08/13/2022] [Indexed: 11/05/2022] Open
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Han S, Park J, Hong SH, Park CS, Choi J, Chae MS. Cardiovascular manifestation of end-stage liver disease and perioperative echocardiography for liver transplantation: anesthesiologist’s view. Anesth Pain Med (Seoul) 2022; 17:132-144. [PMID: 35538654 PMCID: PMC9091670 DOI: 10.17085/apm.22132] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/15/2022] [Accepted: 03/30/2022] [Indexed: 11/19/2022] Open
Abstract
Liver transplantation (LT) is the curative therapy for decompensated cirrhosis. However, anesthesiologists can find it challenging to manage patients undergoing LT due to the underlying pathologic conditions of patients with end-stage liver disease and the high invasiveness of the procedure, which is frequently accompanied by massive blood loss. Echocardiography is a non-invasive or semi-invasive imaging tool that provides real-time information about the structural and functional status of the heart and is considered to be able to improve outcomes by enabling accurate and detailed assessments. This article reviews the pathophysiologic changes of the heart accompanied by cirrhosis that mainly affect hemodynamics. We also present a comparative review of the diagnostic criteria for cirrhotic cardiomyopathy published by the World Congress of Gastroenterology in 2005 and the Cirrhotic Cardiomyopathy Consortium in 2019. This article discusses the conditions that could affect hemodynamic stability and postoperative outcomes, such as coronary artery disease, left ventricular outflow tract obstruction, portopulmonary hypertension, hepatopulmonary syndrome, pericardial effusion, cardiac tamponade, patent foramen ovale, and ascites. Finally, we cover a number of intraoperative factors that should be considered, including intraoperative blood loss, rapid reaccumulation of ascites, manipulation of the inferior vena cava, post-reperfusion syndrome, and adverse effects of excessive fluid infusion and transfusion. This article aimed to summarize the cardiovascular manifestations of cirrhosis that can affect hemodynamics and can be evaluated using perioperative echocardiography. We hope that this article will provide information about the hemodynamic characteristics of LT recipients and stimulate more active use of perioperative echocardiography.
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Affiliation(s)
- Sangbin Han
- Department of Emergency Medicine, Cheongyang Health Center County Hospital, Cheongyang, Korea
| | - Jaesik Park
- Department of Anesthesiology and Pain Medicine, Seoul St. Mary’s Hospital, College of Medicine, The Catholic University of Korea, Seoul, Korea
| | - Sang Hyun Hong
- Department of Anesthesiology and Pain Medicine, Seoul St. Mary’s Hospital, College of Medicine, The Catholic University of Korea, Seoul, Korea
| | - Chul Soo Park
- Department of Anesthesiology and Pain Medicine, Seoul St. Mary’s Hospital, College of Medicine, The Catholic University of Korea, Seoul, Korea
| | - Jongho Choi
- Department of Anesthesiology and Pain Medicine, Seoul St. Mary’s Hospital, College of Medicine, The Catholic University of Korea, Seoul, Korea
| | - Min Suk Chae
- Department of Anesthesiology and Pain Medicine, Seoul St. Mary’s Hospital, College of Medicine, The Catholic University of Korea, Seoul, Korea
- Corresponding author Min Suk Chae, M.D., Ph.D. Department of Anesthesiology and Pain Medicine, Seoul St. Mary’s Hospital, College of Medicine, The Catholic University of Korea, 222 Banpo-daero, Seocho-gu, Seoul 06591, Korea Tel: 82-2-2258-6150 Fax: 82-2-537-1951 E-mail:
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Liu H, Nguyen HH, Yoon KT, Lee SS. Pathogenic Mechanisms Underlying Cirrhotic Cardiomyopathy. FRONTIERS IN NETWORK PHYSIOLOGY 2022; 2:849253. [PMID: 36926084 PMCID: PMC10013066 DOI: 10.3389/fnetp.2022.849253] [Citation(s) in RCA: 9] [Impact Index Per Article: 4.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Received: 01/05/2022] [Accepted: 02/18/2022] [Indexed: 12/14/2022]
Abstract
Cardiac dysfunction associated with cirrhosis in the absence of preexisting heart disease is a condition known as cirrhotic cardiomyopathy (CCM). Cardiac abnormalities consist of enlargement of cardiac chambers, attenuated systolic and diastolic contractile responses to stress stimuli, and repolarization changes. CCM may contribute to cardiovascular morbidity and mortality after liver transplantation and other major surgeries, and also to the pathogenesis of hepatorenal syndrome. The underlying mechanisms of CCM are poorly understood and as such medical therapy is an area of unmet medical need. The present review focuses on the pathogenic mechanisms responsible for development of CCM. The two major concurrent mechanistic pathways are the inflammatory phenotype due to portal hypertension, and protein/lipid synthetic/metabolic defects due to cirrhosis and liver insufficiency. The inflammatory phenotype arises from intestinal congestion due to portal hypertension, resulting in bacteria/endotoxin translocation into the systemic circulation. The cytokine storm associated with inflammation, particularly TNFα acting via NFκB depresses cardiac function. They also stimulate two evanescent gases, nitric oxide and carbon monoxide which produce cardiodepression by cGMP. Inflammation also stimulates the endocannabinoid CB-1 pathway. These systems inhibit the stimulatory beta-adrenergic contractile pathway. The liver insufficiency of cirrhosis is associated with defective synthesis or metabolism of several substances including proteins and lipids/lipoproteins. The protein defects including titin and collagen contribute to diastolic dysfunction. Other protein abnormalities such as a switch of myosin heavy chain isoforms result in systolic dysfunction. Lipid biochemical changes at the cardiac sarcolemmal plasma membrane result in increased cholesterol:phospholipid ratio and decreased membrane fluidity. Final common pathway changes involve abnormal cardiomyocyte intracellular ion kinetics, particularly calcium. In conclusion, cirrhotic cardiomyopathy is caused by two pathways of cellular and molecular dysfunction/damage due to hepatic insufficiency and portal hypertension.
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Affiliation(s)
- Hongqun Liu
- Liver Unit, University of Calgary Cumming School of Medicine, Calgary, AB, Canada
| | - Henry H Nguyen
- Liver Unit, University of Calgary Cumming School of Medicine, Calgary, AB, Canada
| | - Ki Tae Yoon
- Liver Center, Pusan National University Yangsan Hospital, Yangsan, South Korea
| | - Samuel S Lee
- Liver Unit, University of Calgary Cumming School of Medicine, Calgary, AB, Canada
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Echocardiography in the Liver Transplant Patient. Curr Cardiol Rep 2021; 23:110. [PMID: 34216273 DOI: 10.1007/s11886-021-01531-1] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Accepted: 05/17/2021] [Indexed: 10/20/2022]
Abstract
PURPOSE OF REVIEW The aim of this study is to review current echocardiographic modalities utilized in the assessment of the preoperative liver transplant candidate with an emphasis on newer techniques. We sought to assess if newer methods imparted additional diagnostic or prognostic accuracy compared to prior methods based on existing studies. RECENT FINDINGS Standard dobutamine stress echocardiography offers important information regarding operative risk and post-operative survival in liver transplant candidates; however, technologies such as speckle-tracking echocardiography (STE) and evaluation of diastolic function have emerged as useful tools as well. 2D-STE and diastolic echocardiography offer additional parameters such as global longitudinal strain and measures of diastolic dysfunction that can better predict peri-operative and post-operative complications in liver transplant candidates. If able, practitioners should utilize these methods routinely in their assessment of liver transplant candidates.
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Ivanova AD, Filatova TS, Abramochkin DV, Atkinson A, Dobrzynski H, Kokaeva ZG, Merzlyak EM, Pustovit KB, Kuzmin VS. Attenuation of inward rectifier potassium current contributes to the α1-adrenergic receptor-induced proarrhythmicity in the caval vein myocardium. Acta Physiol (Oxf) 2021; 231:e13597. [PMID: 33306261 DOI: 10.1111/apha.13597] [Citation(s) in RCA: 6] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/21/2020] [Revised: 11/19/2020] [Accepted: 12/07/2020] [Indexed: 12/31/2022]
Abstract
AIM This study is aimed at investigation of electrophysiological effects of α1-adrenoreceptor (α1-AR) stimulation in the rat superior vena cava (SVC) myocardium, which is one of the sources of proarrhythmic activity. METHODS α1-ARs agonists (phenylephrine-PHE or norepinephrine in presence of atenolol-NE + ATL) were applied to SVC and atrial tissue preparations or isolated cardiomyocytes, which were examined using optical mapping, glass microelectrodes or whole-cell patch clamp. α1-ARs distribution was evaluated using immunofluorescence. Kir2.X mRNA and protein level were estimated using RT-PCR and Western blotting. RESULTS PHE or NE + ATL application caused a significant suppression of the conduction velocity (CV) of excitation and inexcitability in SVC, an increase in the duration of electrically evoked action potentials (APs), a decrease in the maximum upstroke velocity (dV/dtmax ) and depolarization of the resting membrane potential (RMP) in SVC to a greater extent than in atria. The effects induced by α1-ARs activation in SVC were attenuated by protein kinase C inhibition (PKC). The whole-cell patch clamp revealed PHE-induced suppression of outward component of IK1 inward rectifier current in isolated SVC, but not atrial myocytes. These effects can be mediated by α1A subtype of α-ARs found in abundance in rat SVC. The basal IK1 level in SVC was much lower than in atria as a result of the weaker expression of Kir2.2 channels. CONCLUSION Therefore, the reduced density of IK1 in rat SVC cardiomyocytes and sensitivity of this current to α1A-AR stimulation via PKC-dependent pathways might lead to proarrhythmic conduction in SVC myocardium by inducing RMP depolarization, AP prolongation, CV and dV/dtmax decrease.
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Affiliation(s)
- Alexandra D. Ivanova
- Department of Human and Animal Physiology Lomonosov Moscow State University Moscow Russia
| | - Tatiana S. Filatova
- Department of Human and Animal Physiology Lomonosov Moscow State University Moscow Russia
- Department of Physiology Pirogov Russian National Research Medical University Moscow Russia
| | - Denis V. Abramochkin
- Department of Human and Animal Physiology Lomonosov Moscow State University Moscow Russia
- Department of Physiology Pirogov Russian National Research Medical University Moscow Russia
- Laboratory of Cardiac Electrophysiology National Medical Research Center for Cardiology Moscow Russia
| | - Andrew Atkinson
- Faculty of Biology, Medicine and Health University of Manchester Manchester UK
| | - Halina Dobrzynski
- Faculty of Biology, Medicine and Health University of Manchester Manchester UK
- Heart Embryology and Anatomy Research Team Department of Anatomy Jagiellonian University Medical College Cracow Poland
| | - Zarema G. Kokaeva
- Department of Human and Animal Physiology Lomonosov Moscow State University Moscow Russia
| | - Ekaterina M. Merzlyak
- Shemiakin‐Ovchinnikov Institute of Bioorganic Chemistry Russian Academy of Science Moscow Russia
| | - Ksenia B. Pustovit
- Department of Human and Animal Physiology Lomonosov Moscow State University Moscow Russia
| | - Vladislav S. Kuzmin
- Department of Human and Animal Physiology Lomonosov Moscow State University Moscow Russia
- Department of Physiology Pirogov Russian National Research Medical University Moscow Russia
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Kim SY, Kim KH, Schilling JM, Leem J, Dhanani M, Head BP, Roth DM, Zemljic-Harpf AE, Patel HH. Protective role of cardiac-specific overexpression of caveolin-3 in cirrhotic cardiomyopathy. Am J Physiol Gastrointest Liver Physiol 2020; 318:G531-G541. [PMID: 31961720 PMCID: PMC7099497 DOI: 10.1152/ajpgi.00346.2019] [Citation(s) in RCA: 7] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 01/31/2023]
Abstract
Cirrhotic cardiomyopathy is a clinical syndrome in patients with liver cirrhosis characterized by blunted cardiac contractile responses to stress and/or heart rate-corrected QT (QTc) interval prolongation. Caveolin-3 (Cav-3) plays a critical role in cardiac protection and is an emerging therapeutic target for heart disease. We investigated the protective role of cardiac-specific overexpression (OE) of Cav-3 in cirrhotic cardiomyopathy. Biliary fibrosis was induced in male Cav-3 OE mice and transgene negative (TGneg) littermates by feeding a diet containing 3,5-diethoxycarbonyl-1,4-dihydrocollidine (DDC; 0.1%) for 3 wk. Liver pathology and blood chemistries were assessed, and stress echocardiography, telemetry, and isolated heart perfusion studies to assess adrenergic responsiveness were performed. Cav-3 OE mice showed a similar degree of hyperdynamic contractility, pulmonary hypertension, and QTc interval prolongation as TGneg mice after 3 wk of DDC diet. Blunted systolic responses were shown in both DDC-fed Cav-3 OE and TGneg hearts after in vivo isoproterenol challenge. However, QTc interval prolongation after in vivo isoproterenol challenge was significantly less in DDC-fed Cav-3 OE hearts compared with DDC-fed TGneg hearts. In ex vivo perfused hearts, where circulatory factors are absent, isoproterenol challenge showed hearts from DDC-fed Cav-3 OE mice had better cardiac contractility and relaxation compared with DDC-fed TGneg hearts. Although Cav-3 OE in the heart did not prevent cardiac alterations in DDC-induced biliary fibrosis, cardiac expression of Cav-3 reduced QTc interval prolongation after adrenergic stimulation in cirrhosis.NEW & NOTEWORTHY Prevalence of cirrhotic cardiomyopathy is up to 50% in cirrhotic patients, and liver transplantation is the only treatment. However, cirrhotic cardiomyopathy is associated with perioperative morbidity and mortality after liver transplantation; therefore, management of cirrhotic cardiomyopathy is crucial for successful liver transplantation. This study shows cardiac myocyte specific overexpression of caveolin-3 (Cav-3) provides better cardiac contractile responses and less corrected QT prolongation during adrenergic stress in a cirrhotic cardiomyopathy model, suggesting beneficial effects of Cav-3 expression in cirrhotic cardiomyopathy.
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Affiliation(s)
- So Yeon Kim
- 1Department of Anesthesiology and Pain Medicine, Anesthesia and Pain Research Institute, Yonsei University College of Medicine, Seoul, Republic of Korea
| | - Kang Ho Kim
- 2Department of Molecular and Cellular Biology, Baylor College of Medicine, Houston, Texas
| | - Jan M. Schilling
- 3Veterans Administration San Diego Healthcare System and the Department of Anesthesiology, University of California, San Diego, School of Medicine, San Diego, California
| | - Joseph Leem
- 3Veterans Administration San Diego Healthcare System and the Department of Anesthesiology, University of California, San Diego, School of Medicine, San Diego, California
| | - Mehul Dhanani
- 3Veterans Administration San Diego Healthcare System and the Department of Anesthesiology, University of California, San Diego, School of Medicine, San Diego, California
| | - Brian P. Head
- 3Veterans Administration San Diego Healthcare System and the Department of Anesthesiology, University of California, San Diego, School of Medicine, San Diego, California
| | - David M. Roth
- 3Veterans Administration San Diego Healthcare System and the Department of Anesthesiology, University of California, San Diego, School of Medicine, San Diego, California
| | - Alice E. Zemljic-Harpf
- 3Veterans Administration San Diego Healthcare System and the Department of Anesthesiology, University of California, San Diego, School of Medicine, San Diego, California
| | - Hemal H. Patel
- 3Veterans Administration San Diego Healthcare System and the Department of Anesthesiology, University of California, San Diego, School of Medicine, San Diego, California
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Arya S, Kumar P, Tiwari B, Belwal S, Saxena S, Abbas H. What Every Intensivist should Know about Impairment of Cardiac Function and Arrhythmias in Liver Disease Patients: A Review. Indian J Crit Care Med 2020; 24:1251-1255. [PMID: 33446981 PMCID: PMC7775933 DOI: 10.5005/jp-journals-10071-23695] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/26/2022] Open
Abstract
Objectives Impairment of cardiac function and arrhythmias often coexist in patients with liver diseases. Many studies have proved this coexistence and put forward various theories toward its pathophysiology. This narrative review tries to find the answers with supporting evidence on five main questions: Materials and methods Clinical evidence was obtained by using search engines, namely, Cochrane Library, PubMed, and Google Scholar. Studies published in journals in the English language, between January 1969 and December 2019, which mentioned the relationship between cardiac arrhythmia and liver disease, were included. We used the keywords: jaundice, bilirubin, arrhythmia, ECG, QTc interval, QT dispersion, liver, and cirrhosis. Relevant animal or human studies answering the five main questions were extracted and reviewed. Conclusion The evidence included in our review sheds light on the fact that approximately 50% of liver cirrhosis cases develop cirrhotic cardiomyopathy (CC) and there has been an association between liver abnormalities and cardiac pathology. The present review also supports that there exists a strong association between high levels of serum bilirubin levels and cardiac arrhythmias, QTc value can be relied upon as a risk factor for predicting imminent arrhythmias, and that it is associated with mortality. Its basic pathophysiology can be explained by the potential action of bile acids in prolonging the QT interval. It also causes cardiac hypertrophy and apoptosis of cardiomyocytes leading to cardiac dysfunction. How to cite this article Arya S, Kumar P, Tiwari B, Belwal S, Saxena S, Abbas H. What Every Intensivist should Know about Impairment of Cardiac Function and Arrhythmias in Liver Disease Patients: A Review. Indian J Crit Care Med 2020;24(12):1251–1255.
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Affiliation(s)
- Sanjeev Arya
- Department of Critical Care, Max Super Specialty Hospital (Previously), Dehradun, India
| | - Prashant Kumar
- Department of Critical Care, Kailash Hospital, Noida, Uttar Pradesh, India
| | - Bhuwan Tiwari
- Department of Cardiology, Ram Manohar Lohia Institute of Medical Sciences, Vibhuti Khand, Gomti Nagar, Lucknow, Uttar Pradesh, India
| | - Shantanu Belwal
- Department of Critical Care, Max Super Specialty Hospital, Dehradun, India
| | - Sanjay Saxena
- Department of Critical Care, Max Super Specialty Hospital, Dehradun, India
| | - Haider Abbas
- Department of ER and Critical Care, King Georges Medical University, Lucknow, Uttar Pradesh, India
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Abstract
In the cirrhotic liver, distortion of the normal liver architecture is caused by structural and vascular changes. Portal hypertension is often associated with a hyperdynamic circulatory syndrome in which cardiac output and heart rate are increased and systemic vascular resistance is decreased. The release of several vasoactive substances is the primary factor involved in the reduction of mesenteric arterial resistance, resulting in sodium and water retention with eventual formation of ascites. Management of these patients with acute cardiac dysfunction often requires invasive hemodynamic monitoring in an intensive care unit setting to tailor decisions regarding use of fluids and vasopressors.
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Affiliation(s)
- Steven M Hollenberg
- Department of Cardiovascular Disease, Cooper University Hospital, 1 Cooper Plaza, Camden, 08103, NJ, USA.
| | - Brett Waldman
- Department of Cardiovascular Disease, Cooper University Hospital, 1 Cooper Plaza, Camden, 08103, NJ, USA
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Saeedi Saravi SS, Ghazi-Khansari M, Ejtemaei Mehr S, Nobakht M, Mousavi SE, Dehpour AR. Contribution of mammalian target of rapamycin in the pathophysiology of cirrhotic cardiomyopathy. World J Gastroenterol 2016; 22:4685-94. [PMID: 27217700 PMCID: PMC4870075 DOI: 10.3748/wjg.v22.i19.4685] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 01/17/2016] [Revised: 02/27/2016] [Accepted: 03/13/2016] [Indexed: 02/06/2023] Open
Abstract
AIM: To explore the role of mammalian target of rapamycin (mTOR) in the pathogenesis of cirrhotic cardiomyopathy and the potential of rapamycin to improve this pathologic condition.
METHODS: Male albino Wistar rats weighing 100-120 g were treated with tetrachloride carbon (CCl4) for 8 wk to induce cirrhosis. Subsequently, animals were administered rapamycin (2 mg/kg per day). The QTc intervals were calculated in a 5-min electrocardiogram. Then, the left ventricular papillary muscles were isolated to examine inotropic responsiveness to β-adrenergic stimulation using a standard organ bath equipped by Powerlab system. Phosphorylated-mTOR localization in left ventricles was immunohistochemically assessed, and ventricular tumor necrosis factor (TNF)-α was measured. Western blot was used to measure levels of ventricular phosphorylated-mTOR protein.
RESULTS: Cirrhosis was confirmed by hematoxylin and eosin staining of liver tissues, visual observation of lethargy, weight loss, jaundice, brown urine, ascites, liver stiffness, and a significant increase of spleen weight (P < 0.001). A significant prolongation in QTc intervals occurred in cirrhotic rats exposed to CCl4 (P < 0.001), while this prolongation was decreased with rapamycin treatment (P < 0.01). CCl4-induced cirrhosis caused a significant decrease of contractile responsiveness to isoproterenol stimulation and a significant increase in cardiac TNF-α. These findings were correlated with data from western blot and immunohistochemical studies on phosphorylated-mTOR expression in left ventricles. Phosphorylated-mTOR was significantly enhanced in cirrhotic rats, especially in the endothelium, compared to controls. Rapamycin treatment significantly increased contractile force and myocardial localization of phosphorylated-mTOR and decreased cardiac TNF-α concentration compared to cirrhotic rats with no treatment.
CONCLUSION: In this study, we demonstrated a potential role for cardiac mTOR in the pathophysiology of cirrhotic cardiomyopathy. Rapamycin normalized the inotropic effect and altered phosphorylated-mTOR expression and myocardial localization in cirrhotic rats.
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Affiliation(s)
- Seyed Soheil Saeedi Saravi
- Seyed Soheil Saeedi Saravi, Mahmoud Ghazi-Khansari, Shahram Ejtemaei Mehr, Seyyedeh Elaheh Mousavi, Ahmad Reza Dehpour, Department of Pharmacology, School of Medicine, Tehran University of Medical Sciences, Tehran 13145, Iran
| | - Mahmoud Ghazi-Khansari
- Seyed Soheil Saeedi Saravi, Mahmoud Ghazi-Khansari, Shahram Ejtemaei Mehr, Seyyedeh Elaheh Mousavi, Ahmad Reza Dehpour, Department of Pharmacology, School of Medicine, Tehran University of Medical Sciences, Tehran 13145, Iran
| | - Shahram Ejtemaei Mehr
- Seyed Soheil Saeedi Saravi, Mahmoud Ghazi-Khansari, Shahram Ejtemaei Mehr, Seyyedeh Elaheh Mousavi, Ahmad Reza Dehpour, Department of Pharmacology, School of Medicine, Tehran University of Medical Sciences, Tehran 13145, Iran
| | - Maliheh Nobakht
- Seyed Soheil Saeedi Saravi, Mahmoud Ghazi-Khansari, Shahram Ejtemaei Mehr, Seyyedeh Elaheh Mousavi, Ahmad Reza Dehpour, Department of Pharmacology, School of Medicine, Tehran University of Medical Sciences, Tehran 13145, Iran
| | - Seyyedeh Elaheh Mousavi
- Seyed Soheil Saeedi Saravi, Mahmoud Ghazi-Khansari, Shahram Ejtemaei Mehr, Seyyedeh Elaheh Mousavi, Ahmad Reza Dehpour, Department of Pharmacology, School of Medicine, Tehran University of Medical Sciences, Tehran 13145, Iran
| | - Ahmad Reza Dehpour
- Seyed Soheil Saeedi Saravi, Mahmoud Ghazi-Khansari, Shahram Ejtemaei Mehr, Seyyedeh Elaheh Mousavi, Ahmad Reza Dehpour, Department of Pharmacology, School of Medicine, Tehran University of Medical Sciences, Tehran 13145, Iran
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Akboga MK, Yuksel M, Balci KG, Kaplan M, Cay S, Gokbulut V, Yayla C, Ertem AG, Ayhan MA, Topaloglu S, Aras D. Tp-e Interval, Tp-e/QTc Ratio, and Fragmented QRS Are Correlated with the Severity of Liver Cirrhosis. Ann Noninvasive Electrocardiol 2016; 22. [PMID: 27061341 DOI: 10.1111/anec.12359] [Citation(s) in RCA: 7] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 12/12/2022] Open
Abstract
BACKGROUND Arrhythmias and electrocardiographic changes are reported in several noncardiac diseases, including liver cirrhosis (LC). We intended to evaluate the interval from the peak to the end of the electrocardiographic T wave (Tp-e), Tp-e/QTc ratio, and fQRS as presumed markers of arrhythmias in LC. METHODS In this cross-sectional study, a total of 88 consecutive patients with LC according to clinical, biological, ultrasonographic, or histological criteria and 73 control subjects were enrolled. The severity of cirrhosis was classified according to Pugh-Child's classification and Model for End-Stage Liver Disease (MELD) score. Tp-e interval, Tp-e/QTc ratio, and fQRS rates were measured from the 12-lead electrocardiogram. RESULTS Tp-e interval, Tp-e/QTc ratio and fQRS rates were significantly increased in parallel to the severity of LC (P < 0.001, P < 0.001, and P = 0.003, respectively). In correlation analysis, Pugh-Child stage showed a significantly positive correlation with Tp-e interval (r = 0.462, P < 0.001), QTc interval (r = 0.373, P < 0.001), Tp-e/QTc ratio (r = 0.352, P < 0.001), and fQRS (r = 0.407, P < 0.001). Furthermore, Tp-e interval (r = 0.414, P < 0.001) and Tp-e/QTc ratio (r = 0.426, P< 0.001) had significant positive correlation with MELD score. CONCLUSIONS Our study demonstrated that Tp-e interval, Tp-e/QTc ratios, and fQRS rates were significantly increased in parallel to the severity of LC. Thus, these findings may implicate that Tp-e interval, Tp-e/QTc ratio, and fQRS may be novel and useful indicators for prediction of arrhythmias in LC.
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Affiliation(s)
- Mehmet Kadri Akboga
- Department of Cardiology, Turkiye Yuksek Ihtisas Training and Research Hospital, Ankara, Turkey
| | - Mahmut Yuksel
- Department of Gastroenterology, Turkiye Yuksek Ihtisas Training and Research Hospital, Ankara, Turkey
| | - Kevser Gulcihan Balci
- Department of Cardiology, Turkiye Yuksek Ihtisas Training and Research Hospital, Ankara, Turkey
| | - Mustafa Kaplan
- Department of Gastroenterology, Turkiye Yuksek Ihtisas Training and Research Hospital, Ankara, Turkey
| | - Serkan Cay
- Department of Cardiology, Turkiye Yuksek Ihtisas Training and Research Hospital, Ankara, Turkey
| | - Volkan Gokbulut
- Department of Gastroenterology, Turkiye Yuksek Ihtisas Training and Research Hospital, Ankara, Turkey
| | - Cagri Yayla
- Department of Cardiology, Turkiye Yuksek Ihtisas Training and Research Hospital, Ankara, Turkey
| | - Ahmet Goktug Ertem
- Department of Cardiology, Turkiye Yuksek Ihtisas Training and Research Hospital, Ankara, Turkey
| | - Meral Akdogan Ayhan
- Department of Gastroenterology, Turkiye Yuksek Ihtisas Training and Research Hospital, Ankara, Turkey
| | - Serkan Topaloglu
- Department of Cardiology, Turkiye Yuksek Ihtisas Training and Research Hospital, Ankara, Turkey
| | - Dursun Aras
- Department of Cardiology, Turkiye Yuksek Ihtisas Training and Research Hospital, Ankara, Turkey
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The heart matters when the liver shatters! Cirrhotic cardiomyopathy: frequency, comparison, and correlation with severity of disease. GASTROENTEROLOGY REVIEW 2016; 11:247-256. [PMID: 28053679 PMCID: PMC5209462 DOI: 10.5114/pg.2016.57962] [Citation(s) in RCA: 9] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Subscribe] [Scholar Register] [Received: 03/13/2015] [Accepted: 11/08/2015] [Indexed: 01/01/2023]
Abstract
Introduction Cirrhotic cardiomyopathy is a visor complication among patients with cirrhosis of the liver, manifesting during stress, exertion, transjuglar intrahepatic portosystemic shunt (TIPS), or liver transplantation. Cirrhotic cardiomyopathy is reported to be most common cause of post transplant mortality after rejection of 7% to 21%. Aim To determine the frequency of cirrhotic cardiomyopathy and was further designed to compare parameters of cardiac dysfunction in patients with or without cirrhotic cardiomyopathy. Material and methods All confirmed cases of cirrhosis with various aetiologies were enrolled. Resting ejection fraction (EF) was determined in all patients. Patients were grouped with resting EF < 55% (suspected cardiomyopathy) or > 55% (without cardiomyopathy). Stress echocardiography with dobutamine infusion in both groups yielded an increase of less than 10% in left ventricular (LV) EF at peak dobutamine infusion confirming systolic dysfunction. The diastolic dysfunction (E/A ratio), electrocardiographic parameter (prolong QT interval), and cardiac biomarker (NT-proBNP) were also determined in both the groups to confirm cirrhotic cardiomyopathy. Results Among 89 patients with cirrhosis, 35 (39.32%) had cirrhotic cardiomyopathy. All components of cirrhotic cardiomyopathy, like systolic dysfunction, diastolic dysfunction, prolong QT interval, and cardiac biomarkers, were found to be statistically significant (p = 0.001) when compared with patients without cardiomyopathy. Cirrhotic cardiomyopathy parameters were positively correlated with advancing liver disease. Conclusions Cirrhotic cardiomyopathy is a frequent but unmasked complication in cirrhosis of the liver. All components of cardiac dysfunction, such as systolic, diastolic, and electrocardiographic changes, are present in patients with cirrhotic cardiomyopathy. Cirrhotic cardiomyopathy is positively correlated to severity of liver disease.
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Abstract
Cirrhotic cardiomyopathy is a cardiac condition observed in patients with cirrhotic regardless of the etiologies. It is characterized by the impaired systolic response to physical stress, diastolic dysfunction, and electrophysiological abnormalities, especially QT interval prolongation. Its pathophysiology and clinical significance has been a focus of various researchers for the past decades. The impairment of β-adrenergic receptor, the increase in endogenous cannabinoids, the presence of cardiosuppressants such as nitric oxide and inflammatory cytokines are the proposed mechanisms of systolic dysfunction. The activation of cardiac renin-angiotensin system and salt retention play the role in the development of cardiac hypertrophy and impaired diastolic function. QT interval prolongation, which is observed in 40-50 % of cirrhotic patients, occurs as a result of the derangement in membrane fluidity and ion channel defect. The increased recognition of this disease will prevent the complications of overt heart failure after procedures such as transjugular intrahepatic portosystemic shunt (TIPS) and liver transplantation. Better understandings of the pathogenesis and pathology of cirrhotic cardiomyopathy is crucial in developing more accurate diagnostic tools and specific treatments of this condition.
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Affiliation(s)
| | - Suthat Liangpunsakul
- Division of Gastroenterology/Hepatology, Department of Medicine, Indiana University Hospital, 550 University Boulevard, UH 4100, Indianapolis, IN 46202-5149, USA; Roudebush Veterans Administration Medical Center, Indiana University, Indianapolis, IN, USA
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13
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Abstract
Cirrhotic cardiomyopathy is a cardiac condition observed in patients with cirrhotic regardless of the etiologies. It is characterized by the impaired systolic response to physical stress, diastolic dysfunction, and electrophysiological abnormalities, especially QT interval prolongation. Its pathophysiology and clinical significance has been a focus of various researchers for the past decades. The impairment of β-adrenergic receptor, the increase in endogenous cannabinoids, the presence of cardiosuppressants such as nitric oxide and inflammatory cytokines are the proposed mechanisms of systolic dysfunction. The activation of cardiac renin-angiotensin system and salt retention play the role in the development of cardiac hypertrophy and impaired diastolic function. QT interval prolongation, which is observed in 40-50 % of cirrhotic patients, occurs as a result of the derangement in membrane fluidity and ion channel defect. The increased recognition of this disease will prevent the complications of overt heart failure after procedures such as transjugular intrahepatic portosystemic shunt (TIPS) and liver transplantation. Better understandings of the pathogenesis and pathology of cirrhotic cardiomyopathy is crucial in developing more accurate diagnostic tools and specific treatments of this condition.
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Affiliation(s)
| | - Suthat Liangpunsakul
- Division of Gastroenterology/Hepatology, Department of Medicine, Indiana University Hospital, 550 University Boulevard, UH 4100, Indianapolis, IN 46202-5149, USA; Roudebush Veterans Administration Medical Center, Indiana University, Indianapolis, IN, USA
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14
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Patel D, Singh P, Katz W, Hughes C, Chopra K, Němec J. QT interval prolongation in end-stage liver disease cannot be explained by nonhepatic factors. Ann Noninvasive Electrocardiol 2014; 19:574-81. [PMID: 24762117 DOI: 10.1111/anec.12161] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 01/10/2023] Open
Abstract
INTRODUCTION QT interval prolongation in patients with end-stage liver disease (ESLD) is common. However, electrolyte abnormalities, renal insufficiency, treatment with QT-prolonging drugs, and other factors known to prolong QT interval independently of liver disease occur frequently in ESLD. Moreover, elevated heart rate may be present in ESLD and result in spurious QTc prolongation if the Bazett formula is used for rate correction. It thus remains unclear whether QT prolongation in ESLD is directly caused by liver failure, or indirectly by these confounding factors. METHODS Medical records of all patients (n = 437) who received orthotopic liver transplantation (OLTx) at our institution between 2008 and 2011 were reviewed. Data from 51 patients with available pre-OLTx dobutamine stress echo (DSE), post-OLTx ECG and without nonhepatic factors affecting QT interval duration were analyzed. For each patient, QT versus RR regression line was calculated from ECG tracings obtained during DSE. The QT interval on post-OLTx ECG was compared with the pre-OLTx QT predicted by the regression line for the same RR interval. RESULTS QT interval shortened significantly post-OLTx (from 394 ± 47 to 364 ± 45 ms at RR interval 750 ± 144 ms; P < 0.002) when compared using the regression method. Corrected QT intervals calculated by Bazett and Fridericia formulas also shortened. Patients with prolonged QT pre-OLTx had significantly higher INR and lower serum albumin. CONCLUSION ESLD impairs ventricular repolarization even in the absence of other known factors affecting repolarization. QT prolongation in ESLD is associated with impaired synthetic liver function.
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Affiliation(s)
- Divyang Patel
- University of Pittsburgh School of Medicine, Pittsburgh, PA
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15
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Abstract
Liver cirrhosis is associated with a wide range of cardiovascular abnormalities including hyperdynamic circulation, cirrhotic cardiomyopathy, and pulmonary vascular abnormalities. The pathogenic mechanisms of these cardiovascular changes are multifactorial and include neurohumoral and vascular dysregulations. Accumulating evidence suggests that cirrhosis-related cardiovascular abnormalities play a major role in the pathogenesis of multiple life-threatening complications including hepatorenal syndrome, ascites, spontaneous bacterial peritonitis, gastroesophageal varices, and hepatopulmonary syndrome. Treatment targeting the circulatory dysfunction in these patients may improve the short-term prognosis while awaiting liver transplantation. Careful fluid management in the immediate post-transplant period is extremely important to avoid cardiac-related complications. Liver transplantation results in correction of portal hypertension and reversal of all the pathophysiological mechanisms that lead to the cardiovascular abnormalities, resulting in restoration of a normal circulation. The following is a review of the pathogenesis and clinical implications of the cardiovascular changes in cirrhosis.
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Affiliation(s)
- Waleed K. Al-Hamoudi
- Gastroenterology and Hepatology Unit, Department of Medicine, King Saud University, Riyadh, Saudi Arabia,Address for correspondence: Dr. Waleed Al-Hamoudi, Gastroenterology and Hepatology Unit (59), Department of Medicine, King Saud University, P.O. Box 2925, Riyadh 11461, Saudi Arabia. E-mail:
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16
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Abstract
Cirrhotic cardiomyopathy is a recently recognized condition in cirrhosis consisting of systolic incompetence under condition of stress, diastolic dysfunction related to altered diastolic relaxation, and electrophysiological abnormalities in the absence of any known cardiac disease. It can be diagnosed by using a combination of electrocardiograph, 2-dimensional echocardiography, and various serum markers such as brain natriuretic factor. The underlying pathogenetic mechanisms include abnormalities in the beta-adrenergic signaling pathway, altered cardiomyocyte membrane fluidity, increased myocardial fibrosis, cardiomyocyte hypertrophy, and ion channel defects. Various compounds for which levels are elevated in cirrhosis such as nitric oxide and carbon monoxide can also exert a negative inotropic effect on the myocardium, whereas excess sodium and volume retention can lead to myocardial hypertrophy. Various toxins can also aggravate the ion channel defects, thereby widening the QRS complex causing prolonged QT intervals. Clinically, systolic incompetence is most evident when cirrhotic patients are placed under stress, whether physical or pharmacological, or when the extent of peripheral arterial vasodilatation demands an increased cardiac output as in the case of bacterial infections. Acute volume overload such as immediately after insertion of a transjugular intrahepatic portosystemic shunt or after liver transplantation can also tip these cirrhotic patients into cardiac failure. Treatment of cirrhotic cardiomyopathy is unsatisfactory. There is some evidence that beta-blockade may help some cirrhotic patients with baseline prolonged QT interval. Long-term aldosterone antagonism may help reduce myocardial hypertrophy. Future studies should include further elucidation of pathogenetic mechanisms so as to develop effective treatment strategies.
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Affiliation(s)
- Florence Wong
- Department of Medicine, Toronto General Hospital, University of Toronto, 9th floor, North Wing, Room 983, 200 Elizabeth Street, Toronto, ON, Canada, M5G 2C4,
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17
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Abstract
Cirrhotic cardiomyopathy is the term used to describe a constellation of features indicative of abnormal heart structure and function in patients with cirrhosis. These include systolic and diastolic dysfunction, electrophysiological changes, and macroscopic and microscopic structural changes. The prevalence of cirrhotic cardiomyopathy remains unknown at present, mostly because the disease is generally latent and shows itself when the patient is subjected to stress such as exercise, drugs, hemorrhage and surgery. The main clinical features of cirrhotic cardiomyopathy include baseline increased cardiac output, attenuated systolic contraction or diastolic relaxation in response to physiologic, pharmacologic and surgical stress, and electrical conductance abnormalities (prolonged QT interval). In the majority of cases, diastolic dysfunction precedes systolic dysfunction, which tends to manifest only under conditions of stress. Generally, cirrhotic cardiomyopathy with overt severe heart failure is rare. Major stresses on the cardiovascular system such as liver transplantation, infections and insertion of transjugular intrahepatic portosystemic stent-shunts (TIPS) can unmask the presence of cirrhotic cardiomyopathy and thereby convert latent to overt heart failure. Cirrhotic cardiomyopathy may also contribute to the pathogenesis of hepatorenal syndrome. Pathogenic mechanisms of cirrhotic cardiomyopathy are multiple and include abnormal membrane biophysical characteristics, impaired β-adrenergic receptor signal transduction and increased activity of negative-inotropic pathways mediated by cGMP. Diagnosis and differential diagnosis require a careful assessment of patient history probing for excessive alcohol, physical examination for signs of hypertension such as retinal vascular changes, and appropriate diagnostic tests such as exercise stress electrocardiography, nuclear heart scans and coronary angiography. Current management recommendations include empirical, nonspecific and mainly supportive measures. The exact prognosis remains unclear. The extent of cirrhotic cardiomyopathy generally correlates to the degree of liver insufficiency. Reversibility is possible (either pharmacological or after liver transplantation), but further studies are needed.
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Affiliation(s)
- Soon Koo Baik
- Dept of Medicine, Yonsei University Wonju College of Medicine, Wonju, South Korea
| | | | - Samuel S Lee
- Liver Unit, University of Calgary, Calgary, Canada
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18
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Abstract
Cardiovascular abnormalities accompany both portal hypertension and cirrhosis. These consist of hyperdynamic circulation, defined as reduced mean arterial pressure and systemic vascular resistance, and increased cardiac output. Despite the baseline increased cardiac output, ventricular inotropic and chronotropic responses to stimuli are blunted, a condition known as cirrhotic cardiomyopathy. Both conditions may play an initiating or aggravating pathogenic role in many of the complications of liver failure or portal hypertension including ascites, variceal bleeding, hepatorenal syndrome and increased postoperative mortality after major surgery or liver transplantation. This review briefly examines the major mechanisms that may underlie these cardiovascular abnormalities, concentrating on nitric oxide, endogenous cannabinoids, central neural activation and adrenergic receptor changes. Future work should address the complex interrelationships between these systems.
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Affiliation(s)
- HongQun Liu
- Liver Unit, Department of Medicine, University of Calgary. 3330 Hospital Drive NW, Calgary, AB, T2N 4N1, Canada
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19
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Abstract
Patients with cirrhosis and portal hypertension exhibit characteristic cardiovascular and pulmonary hemodynamic changes. A vasodilatatory state and a hyperdynamic circulation affecting the cardiac and pulmonary functions dominate the circulation. The recently defined cirrhotic cardiomyopathy may affect systolic and diastolic functions, and imply electromechanical abnormalities. In addition, the baroreceptor function and regulation of the circulatory homoeostasis is impaired. Pulmonary dysfunction involves diffusing abnormalities with the development of the hepatopulmonary syndrome and portopulmonary hypertension in some patients. Recent research has focused on the assertion that the hemodynamic and neurohumoral dysregulation are of major importance for the development of the cardiovascular and pulmonary complications in cirrhosis. This aspect is important to take into account in the management of these patients.
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20
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Shimoni Y, Hunt D, Chen K, Emmett T, Kargacin G. Differential autocrine modulation of atrial and ventricular potassium currents and of oxidative stress in diabetic rats. Am J Physiol Heart Circ Physiol 2005; 290:H1879-88. [PMID: 16339825 DOI: 10.1152/ajpheart.01045.2005] [Citation(s) in RCA: 11] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 11/22/2022]
Abstract
The autocrine modulation of cardiac K(+) currents was compared in ventricular and atrial cells (V and A cells, respectively) from Type 1 diabetic rats. K(+) currents were measured by using whole cell voltage clamp. ANG II was measured by ELISA and immunofluorescent labeling. Oxidative stress was assessed by immunofluorescent labeling with dihydroethidium, a measure of superoxide ions. In V cells, K(+) currents are attenuated after activation of the renin-angiotensin system (RAS) and the resulting ANG II-mediated oxidative stress. In striking contrast, these currents are not attenuated in A cells. Inhibition of the angiotensin-converting enzyme (ACE) also has no effect, in contrast to current augmentation in V cells. ANG II levels are enhanced in V, but not in A, cells. However, the high basal ANG II levels in A cells suggest that in these cells, ANG II-mediated pathways are suppressed, rather than ANG II formation. Concordantly, superoxide ion levels are lower in diabetic A than in V cells. Several findings indicate that high atrial natriuretic peptide (ANP) levels in A cells inhibit RAS activation. In male diabetic V cells, in vitro ANP (300 nM-1 muM, >5 h) decreases oxidative stress and augments K(+) currents, but not when excess ANG II is present. ANP has no effect on ventricular K(+) currents when the RAS is not activated, as in control males, in diabetic males treated with ACE inhibitor and in diabetic females. In conclusion, the modulation of K(+) currents and oxidative stress is significantly different in A and V cells in diabetic rat hearts. The evidence suggests that this is largely due to inhibition of RAS activation and/or action by ANP in A cells. These results may underlie chamber-specific arrhythmogenic mechanisms.
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Affiliation(s)
- Yakhin Shimoni
- Department of Physiology and Biophysics, Health Sciences Centre, University of Calgary, Alberta, Canada T2N 4N1.
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21
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Henriksen JH, Bendtsen F, Hansen EF, Møller S. Acute non-selective beta-adrenergic blockade reduces prolonged frequency-adjusted Q-T interval (QTc) in patients with cirrhosis. J Hepatol 2004; 40:239-46. [PMID: 14739094 DOI: 10.1016/j.jhep.2003.10.026] [Citation(s) in RCA: 90] [Impact Index Per Article: 4.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 12/30/2022]
Abstract
BACKGROUND/AIMS Earlier studies have shown a prolonged frequency-adjusted Q-T interval (QTc>0.440 s(1/2)) in a substantial fraction of patients with cirrhosis. The effect of beta-blockade on QTc is unknown, and its determination was the aim of the study. METHODS Seventeen patients with cirrhosis received 80 mg propranolol orally during a haemodynamic investigation with measurements at baseline and 90 min after propranolol ingestion. RESULTS Beta-blockade reduced cardiac output (-21%, P<0.001), heart rate (-20%, P<0.001), and the hepatic venous pressure gradient (HVPG, -17%, P<0.02). The mean QTc=0.460 s(1/2) was prolonged compared to 0.410 s(1/2) in age-matched controls (P<0.01). Whereas QTc decreased during beta-blockade in the cirrhotic patients (from 0.460 to 0.440 s(1/2), P<0.01), no effect was found in the subgroup with normal QTc (0.429 vs. 0.422 s(1/2), ns), and a reduction was seen in the patients with prolonged QTc (from 0.488 to 0.456 s(1/2), P<0.01). The percentage decrease in QTc was related to the reduction in HVPG (r=0.48, P=0.03) and cardiac output (r=0.56, P=0.02). CONCLUSIONS Acute non-selective beta-blockade reduces prolonged QTc towards normal values in patients with cirrhosis. The clinical significance of QTc reduction in arrhythmia is a topic for future research.
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Affiliation(s)
- Jens H Henriksen
- Department of Clinical Physiology, University of Copenhagen, 239, Hvidovre Hospital, DK-2650 Hvidovre, Denmark.
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22
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Pandit SV, Giles WR, Demir SS. A mathematical model of the electrophysiological alterations in rat ventricular myocytes in type-I diabetes. Biophys J 2003; 84:832-41. [PMID: 12547767 PMCID: PMC1302663 DOI: 10.1016/s0006-3495(03)74902-9] [Citation(s) in RCA: 50] [Impact Index Per Article: 2.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/16/2022] Open
Abstract
Our mathematical model of the rat ventricular myocyte (Pandit et al., 2001) was utilized to explore the ionic mechanism(s) that underlie the altered electrophysiological characteristics associated with the short-term model of streptozotocin-induced, type-I diabetes. The simulations show that the observed reductions in the Ca(2+)-independent transient outward K(+) current (I(t)) and the steady-state outward K(+) current (I(ss)), along with slowed inactivation of the L-type Ca(2+) current (I(CaL)), can result in the prolongation of the action potential duration, a well-known experimental finding. In addition, the model demonstrates that the slowed reactivation kinetics of I(t) in diabetic myocytes can account for the more pronounced rate-dependent action potential duration prolongation in diabetes, and that a decrease in the electrogenic Na(+)-K(+) pump current (I(NaK)) results in a small depolarization in the resting membrane potential (V(rest)). This depolarization reduces the availability of the Na(+) channels (I(Na)), thereby resulting in a slower upstroke (dV/dt(max)) of the diabetic action potential. Additional simulations suggest that a reduction in the magnitude of I(CaL), in combination with impaired sarcoplasmic reticulum uptake can lead to a decreased sarcoplasmic reticulum Ca(2+) load. These factors contribute to characteristic abnormal [Ca(2+)](i) homeostasis (reduced peak systolic value and rate of decay) in myocytes from diabetic animals. In combination, these simulation results provide novel information and integrative insights concerning plausible ionic mechanisms for the observed changes in cardiac repolarization and excitation-contraction coupling in rat ventricular myocytes in the setting of streptozotocin-induced, type-I diabetes.
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Affiliation(s)
- Sandeep V Pandit
- Joint Graduate Program in Biomedical Engineering, The University of Memphis, Memphis, Tennessee 38152-3210, USA
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23
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Henriksen JH, Fuglsang S, Bendtsen F, Christensen E, Møller S. Dyssynchronous electrical and mechanical systole in patients with cirrhosis. J Hepatol 2002; 36:513-20. [PMID: 11943423 DOI: 10.1016/s0168-8278(02)00010-7] [Citation(s) in RCA: 76] [Impact Index Per Article: 3.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 12/11/2022]
Abstract
BACKGROUND/AIMS Previous investigations have shown a prolonged QT interval in some patients with cirrhosis. The aim of this study was to investigate the relation between electrical and mechanical systole in patients with different degrees of severity of cirrhosis. METHODS Forty-eight patients with cirrhosis and portal hypertension, studied during a haemodynamic investigation, were compared to 17 controls. RESULTS A prolonged QTc (above 0.440 s(1/2)) was found in 37% of the cirrhotic patients vs. 5.9% in the controls (P=0.03), and there was a correlation to liver dysfunction (P<0.02). A direct relation between QT and time of mechanical systole (tS) was observed in controls (r=0.58, P<0.01), and cirrhotic patients (r=0.44, P<0.002). In patients with a prolonged QTc interval, the difference between electrical and mechanical systole time was substantially longer than in patients with a normal QTc interval (0.078 vs. 0.031 s, P<0.005). The QT values were related to markers of hyperdynamic circulation (r=-0.48 to 0.56, P<0.05-0.001). CONCLUSIONS; Prolonged repolarization, as evidenced by prolonged QTc, is related to both impaired liver function and systemic circulatory dysfunction. In addition these patients have alterations in the cardiac excitation-contraction relation with compromised association between electrical and mechanical function.
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Affiliation(s)
- Jens H Henriksen
- Department of Clinical Physiology and Nuclear Medicine, 239, Hvidovre Hospital, University of Copenhagen, DK-2650 Hvidovre, Denmark.
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24
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Møller S, Henriksen JH. Cirrhotic cardiomyopathy: a pathophysiological review of circulatory dysfunction in liver disease. Heart 2002; 87:9-15. [PMID: 11751653 PMCID: PMC1766971 DOI: 10.1136/heart.87.1.9] [Citation(s) in RCA: 232] [Impact Index Per Article: 10.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Accepted: 09/12/2001] [Indexed: 12/13/2022] Open
Abstract
The systemic circulation in patients with cirrhosis is hyperdynamic with an increased cardiac output and heart rate and a reduced systemic vascular resistance as the most pronounced alterations. The concomitant cardiac dysfunction has recently been termed "cirrhotic cardiomyopathy", which is an entity different from that seen in alcoholic heart muscle disease. Clinically, these patients present with sodium fluid retention and strain often unmasks the presence of latent heart failure. No specific treatment can yet be recommended but caution should be used with respect to procedures that may stress the heart such as shunt implantation and liver transplantation.
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Affiliation(s)
- S Møller
- Department of Clinical Physiology, 239, Hvidovre Hospital, University of Copenhagen, DK-2650 Hvidovre, Denmark.
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25
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Clark RB, Tremblay A, Melnyk P, Allen BG, Giles WR, Fiset C. T-tubule localization of the inward-rectifier K(+) channel in mouse ventricular myocytes: a role in K(+) accumulation. J Physiol 2001; 537:979-92. [PMID: 11744770 PMCID: PMC2278989 DOI: 10.1111/j.1469-7793.2001.00979.x] [Citation(s) in RCA: 35] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/27/2022] Open
Abstract
1. The properties of the slow inward 'tail currents' (I(tail)) that followed depolarizing steps in voltage-clamped, isolated mouse ventricular myocytes were examined. Depolarizing steps that produced large outward K(+) currents in these myocytes were followed by a slowly decaying inward I(tail) on repolarization to the holding potential. These currents were produced only by depolarizations: inwardly rectifying K(+) currents, I(K1), produced by steps to potentials negative to the holding potential, were not followed by I(tail). 2. For depolarizations of equal duration, the magnitude of I(tail) increased as the magnitude of outward current at the end of the depolarizing step increased. The apparent reversal potential of I(tail) was dependent upon the duration of the depolarizing step, and the reversal potential shifted to more depolarized potentials as the duration of the depolarization was increased. 3. Removal of external Na(+) and Ca(2+) had no significant effect on the magnitude or time course of I(tail). BaCl(2) (0.25 mM), which had no effect on the magnitude of outward currents, abolished I(tail) and I(K1) simultaneously. 4. Accordingly, I(tail) in mouse ventricular myocytes probably results from K(+) accumulation in a restricted extracellular space such as the transverse tubule system (t-tubules). The efflux of K(+) into the t-tubules during outward currents produced by depolarization shifts the K(+) Nernst potential (E(K)) from its 'resting' value (close to -80 mV) to more depolarized potentials. This suggests that I(tail) is produced by I(K1) in the t-tubules and is inward because of the transiently elevated K(+) concentration and depolarized value of E(K) in the t-tubules. 5. Additional evidence for the localization of I(K1) channels in the t-tubules was provided by confocal microscopy using a specific antibody against Kir2.1 in mouse ventricular myocytes.
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Affiliation(s)
- R B Clark
- Department of Physiology, University of Calgary, Faculty of Medicine, Calgary, Alberta, T2N 4N1, Canada
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26
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Pandit SV, Clark RB, Giles WR, Demir SS. A mathematical model of action potential heterogeneity in adult rat left ventricular myocytes. Biophys J 2001; 81:3029-51. [PMID: 11720973 PMCID: PMC1301767 DOI: 10.1016/s0006-3495(01)75943-7] [Citation(s) in RCA: 236] [Impact Index Per Article: 10.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/21/2022] Open
Abstract
Mathematical models were developed to reconstruct the action potentials (AP) recorded in epicardial and endocardial myocytes isolated from the adult rat left ventricle. The main goal was to obtain additional insight into the ionic mechanisms responsible for the transmural AP heterogeneity. The simulation results support the hypothesis that the smaller density and the slower reactivation kinetics of the Ca(2+)-independent transient outward K(+) current (I(t)) in the endocardial myocytes can account for the longer action potential duration (APD), and more prominent rate dependence in that cell type. The larger density of the Na(+) current (I(Na)) in the endocardial myocytes results in a faster upstroke (dV/dt(max)). This, in addition to the smaller magnitude of I(t), is responsible for the larger peak overshoot of the simulated endocardial AP. The prolonged APD in the endocardial cell also leads to an enhanced amplitude of the sustained K(+) current (I(ss)), and a larger influx of Ca(2+) ions via the L-type Ca(2+) current (I(CaL)). The latter results in an increased sarcoplasmic reticulum (SR) load, which is mainly responsible for the higher peak systolic value of the Ca(2+) transient [Ca(2+)](i), and the resultant increase in the Na(+)-Ca(2+) exchanger (I(NaCa)) activity, associated with the simulated endocardial AP. In combination, these calculations provide novel, quantitative insights into the repolarization process and its naturally occurring transmural variations in the rat left ventricle.
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Affiliation(s)
- S V Pandit
- Joint Graduate Program in Biomedical Engineering, The University of Memphis, Tennessee 38152-3210, USA
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