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Bavendiek U, Großhennig A, Schwab J, Berliner D, Liu X, Maier L, Gaspar T, Rieth A, Philipp S, Hambrecht R, Westenfeld R, Münzel T, Winkler S, Hülsmann M, Westermann D, Zdravkovic M, Lichtinghagen R, von der Leyen H, Zimmermann S, Veltmann C, Böhm M, Störk S, Koch A, Bauersachs J. Simple and safe digitoxin dosing in heart failure based on data from the DIGIT-HF trial. Clin Res Cardiol 2023:10.1007/s00392-023-02199-z. [PMID: 37087503 PMCID: PMC10359203 DOI: 10.1007/s00392-023-02199-z] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 01/19/2023] [Accepted: 04/03/2023] [Indexed: 04/24/2023]
Abstract
BACKGROUND The present study aimed to develop a simple dosing score when starting the cardiac glycoside digitoxin in heart failure with reduced ejection fraction (HFrEF) employing first data from the randomized, double-blinded DIGIT-HF trial. METHODS AND RESULTS In DIGIT-HF, digitoxin was started with a dose of 0.07 mg once daily (o.d.) in all patients. For score derivation, 317 patients were analyzed who had been randomized to digitoxin. In these patients, after scheduled determination of serum levels at study week 6, the digitoxin dose had remained unchanged or had been reduced to 0.05 mg o.d. (97% of patients) to achieve serum concentrations within a predefined range (10.5-23.6 nmol/l). In logistic regression analyses, sex, age, body mass index (BMI), and estimated glomerular filtration rate (eGFR) were associated with need for dose reduction and, therefore, selected for further developing the dosing score. Optimal cut-points were derived from ROC curve analyses. Finally, female sex, age ≥ 75 years, eGFR < 50 ml/min/1.73 m2, and BMI < 27 kg/m2 each were assigned one point for the digitoxin dosing score. A score of ≥ 1 indicated the need for dose reduction with sensitivity/specificity of 81.6%/49.7%, respectively. Accuracy was confirmed in a validation data set including 64 patients randomized to digitoxin yielding sensitivity/specificity of 87.5%/37.5%, respectively. CONCLUSION In patients with HFrEF, treatment with digitoxin should be started at 0.05 mg o.d. in subjects with either female sex, eGFR < 50 ml/min/1.73m2, BMI < 27 kg/m2, or age ≥ 75 years. In any other patient, digitoxin may be safely started at 0.07 mg o.d.
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Affiliation(s)
- Udo Bavendiek
- Department of Cardiology and Angiology, Hannover Medical School, Carl-Neuberg-Straße 1, 30625, Hannover, Germany.
| | - Anika Großhennig
- Institute of Biostatistics, Hannover Medical School, Hannover, Germany
| | - Johannes Schwab
- Department of Cardiology, Paracelsus Medical University, Nuremberg, Germany
| | - Dominik Berliner
- Department of Cardiology and Angiology, Hannover Medical School, Carl-Neuberg-Straße 1, 30625, Hannover, Germany
| | - Xiaofei Liu
- Institute of Biostatistics, Hannover Medical School, Hannover, Germany
| | - Lars Maier
- Department for Internal Medicine II, University Hospital Regensburg, Regensburg, Germany
| | - Thomas Gaspar
- Department of Internal and Cardiovascular Medicine, Herzzentrum Dresden, University Clinic, Technische Universität Dresden, Dresden, Germany
| | - Andreas Rieth
- Department of Cardiology, Kerckhoff-Klinik, Bad Nauheim, Germany
| | - Sebastian Philipp
- Department of Internal Medicine, Cardiology and Intensive Care Medicine, Elbeklinikum Stade, Stade, Germany
| | - Rainer Hambrecht
- Department of Internal Medicine II, Cardiology, Angiology and Intensive Care Medicine, Klinkum Links Der Weser, Bremen, Germany
| | - Ralf Westenfeld
- Division of Cardiology, Pulmonology and Vascular Medicine, Medical Faculty, University Hospital Duesseldorf, Heinrich-Heine University Duesseldorf, Duesseldorf, Germany
| | - Thomas Münzel
- University Medical Center Mainz, Center of Cardiology, Johannes Gutenberg University, Mainz, Germany
| | - Sebastian Winkler
- Department of Internal Medicine, BG Klinikum Unfallkrankenhaus Berlin, Berlin, Germany
| | - Martin Hülsmann
- Universitätsklinik Für Innere Medizin II, Abteilung Kardiologie, Medizinische Universität Wien, Vienna, Austria
| | - Dirk Westermann
- Department of Cardiology and Angiology, University Heart Center Freiburg-Bad Krozingen, Faculty of Medicine, University of Freiburg, Freiburg, Germany
| | - Marja Zdravkovic
- University Hospital Medical Center Bezanujska Kosa, Belgrade, Serbia
| | - Ralf Lichtinghagen
- Institute for Clinical Chemistry, Hannover Medical School, Hannover, Germany
| | | | - Silke Zimmermann
- Center for Clinical Trials, Hannover Medical School, Hannover, Germany
| | | | - Michael Böhm
- Klinik Für Innere Medizin III, Universitätsklinikum Des Saarlandes, Saarland University, Homburg a. d. Saar, Germany
| | - Stefan Störk
- Department Clincical Reserch & Epidemiology, Comprehensive Heart Failure Center, University Hospital Würzburg, Würzburg, Germany
| | - Armin Koch
- Institute of Biostatistics, Hannover Medical School, Hannover, Germany
| | - Johann Bauersachs
- Department of Cardiology and Angiology, Hannover Medical School, Carl-Neuberg-Straße 1, 30625, Hannover, Germany
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Bavendiek U, Berliner D, Dávila LA, Schwab J, Maier L, Philipp SA, Rieth A, Westenfeld R, Piorkowski C, Weber K, Hänselmann A, Oldhafer M, Schallhorn S, von der Leyen H, Schröder C, Veltmann C, Störk S, Böhm M, Koch A, Bauersachs J. Rationale and design of the DIGIT-HF trial (DIGitoxin to Improve ouTcomes in patients with advanced chronic Heart Failure): a randomized, double-blind, placebo-controlled study. Eur J Heart Fail 2019; 21:676-684. [PMID: 30892806 PMCID: PMC6607489 DOI: 10.1002/ejhf.1452] [Citation(s) in RCA: 49] [Impact Index Per Article: 9.8] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 11/19/2018] [Revised: 01/31/2019] [Accepted: 02/06/2019] [Indexed: 12/11/2022] Open
Abstract
AIMS Despite recent advances in the treatment of chronic heart failure (HF), mortality and hospitalizations still remain high. Additional therapies to improve mortality and morbidity are urgently needed. The efficacy of cardiac glycosides - although regularly used for HF treatment - remains unclear. DIGIT-HF was designed to demonstrate that digitoxin on top of standard of care treatment improves mortality and morbidity in patients with HF and a reduced ejection fraction (HFrEF). METHODS Patients with chronic HF, New York Heart Association (NYHA) functional class III-IV and left ventricular ejection fraction (LVEF) ≤ 40%, or patients in NYHA functional class II and LVEF ≤ 30% are randomized 1:1 in a double-blind fashion to treatment with digitoxin (target serum concentration 8-18 ng/mL) or matching placebo. Randomization is stratified by centre, sex, NYHA functional class (II, III, or IV), atrial fibrillation, and treatment with cardiac glycosides at baseline. A total of 2190 eligible patients will be included in this clinical trial (1095 per group). All patients receive standard of care treatment recommended by expert guidelines upon discretion of the treating physician. The primary outcome is a composite of all-cause mortality or hospital admission for worsening HF (whatever occurs first). Key secondary endpoints are all-cause mortality, hospital admission for worsening HF, and recurrent hospital admission for worsening HF. CONCLUSION The DIGIT-HF trial will provide important evidence, whether the cardiac glycoside digitoxin reduces the risk for all-cause mortality and/or hospital admission for worsening HF in patients with advanced chronic HFrEF on top of standard of care treatment.
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Affiliation(s)
- Udo Bavendiek
- Department of Cardiology and AngiologyHannover Medical SchoolHannoverGermany
| | - Dominik Berliner
- Department of Cardiology and AngiologyHannover Medical SchoolHannoverGermany
| | | | - Johannes Schwab
- Department of Cardiology, Cardiovascular Center, Clinical Center NuernbergParacelsus Medical UniversityNuernbergGermany
| | - Lars Maier
- Department of Internal Medicine IIUniversity Medical Center RegensburgRegensburgGermany
| | - Sebastian A. Philipp
- Department of Cardiology and Intensive Care MedicineElbe Clinic StadeStadeGermany
| | - Andreas Rieth
- Department of Cardiology, Kerckhoff HeartRheuma and Thoracic CenterBad NauheimGermany
| | - Ralf Westenfeld
- Department of Cardiology, Pulmonology, and Vascular Medicine, Medical FacultyUniversity DuesseldorfDuesseldorfGermany
| | - Christopher Piorkowski
- Department of Electrophysiology, Heart CenterUniversity of Technology DresdenDresdenGermany
| | - Kristina Weber
- Department of BiostatisticsHannover Medical SchoolHannoverGermany
| | - Anja Hänselmann
- Department of Cardiology and AngiologyHannover Medical SchoolHannoverGermany
| | | | - Sven Schallhorn
- Department of Cardiology and AngiologyHannover Medical SchoolHannoverGermany
| | | | - Christoph Schröder
- Institute of Clinical PharmacologyHannover Medical SchoolHannoverGermany
| | - Christian Veltmann
- Department of Cardiology and AngiologyHannover Medical SchoolHannoverGermany
| | - Stefan Störk
- Department of Internal Medicine IUniversity Hospital WuerzburgWuerzburgGermany
| | - Michael Böhm
- Department of Internal Medicine IIIUniversity Hospital of the SaarlandHomburgGermany
| | - Armin Koch
- Department of BiostatisticsHannover Medical SchoolHannoverGermany
| | - Johann Bauersachs
- Department of Cardiology and AngiologyHannover Medical SchoolHannoverGermany
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Sessa M, Mascolo A, Andersen MP, Rosano G, Rossi F, Capuano A, Torp-Pedersen C. Effect of Chronic Kidney Diseases on Mortality among Digoxin Users Treated for Non-Valvular Atrial Fibrillation: A Nationwide Register-Based Retrospective Cohort Study. PLoS One 2016; 11:e0160337. [PMID: 27467520 PMCID: PMC4965154 DOI: 10.1371/journal.pone.0160337] [Citation(s) in RCA: 15] [Impact Index Per Article: 1.9] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/17/2016] [Accepted: 07/18/2016] [Indexed: 12/20/2022] Open
Abstract
PURPOSE This study investigated the impact of chronic kidney disease on all-causes and cardiovascular mortality in patients with atrial fibrillation treated with digoxin. METHODS All patients with non-valvular atrial fibrillation and/or atrial flutter as hospitalization diagnosis from January 1, 1997 to December 31, 2012 were identified in Danish nationwide administrative registries. Cox proportional hazard model was used to compare the adjusted risk of all-causes and cardiovascular mortality among patients with and without chronic kidney disease and among patients with different chronic kidney disease stages within 180 days and 2 years from the first digoxin prescription. RESULTS We identified 37,981 patients receiving digoxin; 1884 patients had the diagnosis of chronic kidney disease. Cox regression analysis showed no statistically significant differences in all-causes (Hazard Ratio, HR 0.89; 95% confident interval, CI 0.78-1.03) and cardiovascular mortality (HR 0.88; 95%CI 0.74-1.05) among patients with and without chronic kidney disease within 180 days of follow-up period. No statistically significant differences was found using a 2 years follow-up period neither for all causes mortality (HR 0.90; 95%CI 0.79-1.03), nor for cardiovascular mortality (HR 0.87; 95%CI 0.74-1.02). No statistically significant differences was found comparing patients with and without estimated Glomerular Filtration Rate <30ml/min/1.73m2 and patients with different stages of chronic kidney disease, for all-causes and cardiovascular mortality within 180 days and 2 years from the first digoxin prescription. CONCLUSIONS This study suggest no direct effect of chronic kidney disease and chronic kidney disease stages on all-causes and cardiovascular mortality within both 180 days and 2 years from the first digoxin prescription in patients treatment-naïve with digoxin for non-valvular atrial fibrillation.
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Affiliation(s)
- Maurizio Sessa
- Department of Experimental Medicine, Section of Pharmacology L. Donatelli, Second University of Naples, Naples, Italy
- * E-mail:
| | - Annamaria Mascolo
- Department of Experimental Medicine, Section of Pharmacology L. Donatelli, Second University of Naples, Naples, Italy
| | | | - Giuseppe Rosano
- IRCCS San Raffaele Pisana, Rome, Italy
- Cardiovascular and Cell Sciences Research Institute, St. George's University of London, London, United Kingdom
| | - Francesco Rossi
- Department of Experimental Medicine, Section of Pharmacology L. Donatelli, Second University of Naples, Naples, Italy
| | - Annalisa Capuano
- Department of Experimental Medicine, Section of Pharmacology L. Donatelli, Second University of Naples, Naples, Italy
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Adams KF, Ghali JK, Herbert Patterson J, Stough WG, Butler J, Bauman JL, Ventura HO, Sabbah H, Mackowiak JI, van Veldhuisen DJ. A perspective on re-evaluating digoxin's role in the current management of patients with chronic systolic heart failure: targeting serum concentration to reduce hospitalization and improve safety profile. Eur J Heart Fail 2014; 16:483-93. [DOI: 10.1002/ejhf.64] [Citation(s) in RCA: 23] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 09/26/2013] [Revised: 11/07/2013] [Accepted: 01/20/2014] [Indexed: 01/11/2023] Open
Affiliation(s)
- Kirkwood F. Adams
- Departments of Medicine and Radiology, School of Medicine, Division of Cardiology; University of North Carolina at Chapel Hill; Chapel Hill NC USA
| | - Jalal K. Ghali
- Division of Cardiology; Mercer University School of Medicine; Macon GA USA
| | - J. Herbert Patterson
- Division of Pharmacotherapy and Experimental Therapeutics; University of North Carolina at Chapel Hill Eshelman School of Pharmacy; Chapel Hill NC USA
| | - Wendy Gattis Stough
- Department of Clinical Research; Campbell University College of Pharmacy and Health Sciences; Buies Creek NC USA
| | - Javed Butler
- Department of Medicine, Division of Cardiology; Emory University; Atlanta GA USA
| | - Jerry L. Bauman
- Departments of Pharmacy Practice and Medicine, Section of Cardiology, Colleges of Pharmacy and Medicine; University of Illinois at Chicago; Chicago IL USA
| | - Hector O. Ventura
- John Ochsner Heart and Vascular Institute, Ochsner Clinical School; The University of Queensland School of Medicine; New Orleans LA USA
| | - Hani Sabbah
- Division of Cardiology; Wayne State University, Henry Ford Health System; Detroit MI USA
| | | | - Dirk J. van Veldhuisen
- Department of Cardiology; University of Groningen, University Medical Center Groningen; Groningen the Netherlands
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Abstract
Most antiarrhythmic drugs fulfil the formal requirements for rational use of therapeutic drug monitoring, as they show highly variable plasma concentration profiles at a given dose and a direct concentration-effect relationship. Therapeutic ranges for antiarrhythmic drugs are, however, often very poorly defined. Effective drug concentrations are based on small studies or studies not designed to establish a therapeutic range, with varying dosage regimens and unstandardised sampling procedures. There are large numbers of nonresponders and considerable overlap between therapeutic and toxic concentrations. Furthermore, no study has ever shown that therapeutic drug monitoring makes a significant difference in clinical outcome. Therapeutic concentration ranges for antiarrhythmic drugs as they exist today can give an overall impression about the drug concentrations required in the majority of patients. They may also be helpful for dosage adjustment in patients with renal or hepatic failure or in patients with possible toxicological or compliance problems. Their use in optimising individual antiarrhythmic therapy, however, is very limited.
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Affiliation(s)
- Gesche Jürgens
- Department of Clinical Pharmacology, Copenhagen University Hospital, Copenhagen, Denmark.
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6
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Adams KF, Gheorghiade M, Uretsky BF, Patterson JH, Schwartz TA, Young JB. Clinical benefits of low serum digoxin concentrations in heart failure. J Am Coll Cardiol 2002; 39:946-53. [PMID: 11897434 DOI: 10.1016/s0735-1097(02)01708-4] [Citation(s) in RCA: 110] [Impact Index Per Article: 5.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 11/30/2022]
Abstract
OBJECTIVES We sought to determine whether there was a relationship between serum digoxin concentration (SDC), including SDCs typically regarded as low, and clinical efficacy related to digoxin in patients with symptomatic left ventricular dysfunction. BACKGROUND Digitalis glycosides have been used for 200 years in the treatment of heart failure (HF), but the SDC required for optimal clinical efficacy and acceptable toxicity remains controversial. METHODS This relationship was investigated by utilizing data from two randomized, double-blinded, placebo-controlled, digoxin-withdrawal trials: the Prospective Randomized study Of Ventricular failure and Efficacy of Digoxin (PROVED) and the Randomized Assessment of Digoxin on Inhibitors of Angiotensin-Converting Enzyme (RADIANCE). Major end points were worsening HF, change in left ventricular ejection fraction and treadmill time after randomization. The primary analysis investigated the relationship between SDC at randomization and these end points. A secondary categorical analysis compared these end points in patients who discontinued digoxin versus patients who continued digoxin and had low (0.5 to 0.9 ng/ml), moderate (0.9 to 1.2 ng/ml) or high (>1.2 ng/ml) SDCs at randomization. RESULTS Multiple regression analysis failed to find a relationship between randomization SDC, considered as a continuous variable, and any study end point (all p > 0.236). Multivariable Cox analysis found that the risk of worsening HF was significantly less (all p < 0.02) for patients in any category of SDC who continued digoxin, as compared with patients withdrawn from digoxin. Specifically, patients in the low SDC category were significantly less likely than placebo patients to experience worsening HF during follow-up (p = 0.018). CONCLUSIONS The beneficial effects of digoxin on common clinical end points in patients with HF were similar, regardless of SDC.
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Affiliation(s)
- Kirkwood F Adams
- Departments of Medicine and Radiology, School of Medicine, University of North Carolina, Chapel Hill, North Carolina 27599-7075, USA.
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7
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Grossmann M. Effects of cardiac glycosides on 24-h ambulatory blood pressure in healthy volunteers and patients with heart failure. Eur J Clin Invest 2001; 31 Suppl 2:26-30. [PMID: 11525235 DOI: 10.1046/j.1365-2362.2001.0310s2026.x] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 11/20/2022]
Abstract
Blood pressure effects of cardiac glycosides in humans have been infrequently reported. Although direct infusion of ouabain or digoxin causes vasoconstriction, indirect effects of cardiac glycosides may have the opposite effect, owing to changes in sympatho-vagal balance. This paper summarises three studies on the effects of cardiac glycosides on circadian blood pressure, utilizing automatic 24-h ambulatory blood pressure measurement (ABPM). In healthy volunteers, 10 days of oral digoxin or digitoxin caused decreases in diastolic blood pressure and heart rate during overnight sleep. No effect was detectable during daytime activities. In patients with heart failure (NYHA stage II), 7 days of oral digoxin also caused a decrease in diastolic blood pressure but only a small increase in systolic pressure during overnight sleep. Again, no effect was detectable during the day. Cardiac glycosides have significant effects on blood pressure, which only appear during overnight sleep, i.e. a phase when sympathetic background activity is lowest. Regular daytime activities may 'overwrite' these effects. Effects of cardiac glycosides on blood pressure may have therapeutic impact, depending on the stage of heart failure and concomitant diseases.
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Affiliation(s)
- M Grossmann
- Institute of Clinical Pharmacology, Faculty of Medicine, University of Technology, Dresden, Germany.
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8
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Abstract
BACKGROUND For the past two decades, it has generally been accepted ('Blaustein hypothesis') that cardiac glycosides such as ouabain and digoxin increase the sodium and calcium content of smooth muscle cells, so inducing arterial vasoconstriction and a rise in blood pressure. Recent data from an experimental study we carried out led us to question this assumption. DESIGN A retrospective literature survey covering 20 years and including animal and human studies was performed. Representative results are presented. RESULTS Contradictory effects of cardiac glycosides on blood pressure and vasculature have been described. Increased, decreased or unaltered blood-pressure values have been observed following administration of the glycosides ouabain, digoxin and digitoxin. Moreover, vasoconstricting as well as vasodilating effects of cardiac glycosides have been demonstrated. Several recent studies show that cardiac glycosides such as digoxin and digitoxin can lead to a reduction of at least diastolic blood pressure. CONCLUSION A slight vasodilation of resistance vessels followed by a fall in diastolic blood pressure could be a contributing factor for the beneficial effects of cardiac glycosides in patients with congestive heart failure. This vasodilation may be caused by central (neurohumoral) effects of digitalis glycosides.
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Affiliation(s)
- W Kirch
- Institute of Clinical Pharmacology, Medical Faculty, Technical University, Dresden, Germany.
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Belz GG, Breithaupt-Grögler K, Osowski U. Treatment of congestive heart failure--current status of use of digitoxin. Eur J Clin Invest 2001; 31 Suppl 2:10-7. [PMID: 11525233 DOI: 10.1046/j.1365-2362.2001.0310s2010.x] [Citation(s) in RCA: 46] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 11/20/2022]
Abstract
Digitalis glycosides exert a positive inotropic effect, i.e. an increase in myocardial contractility associated with a prolongation of relaxation period, and glycosides lower the heart rate (negative chronotropic), impede stimulus conduction (negative dromotropic) and promote myocardial excitability (positive bathmotropic). They seem to influence the activities of both the vagal and the sympathetic systems. Digitalis glycosides that belong to different substance classes are closely comparable concerning pharmacodynamics but differ substantially in regard to pharmacokinetics. Digoxin and its derivatives are less lipophilic, show lower protein binding and shorter half-life, are mainly eliminated via the kidney and accumulate rather rapidly in cases of insufficient kidney function. Digitoxin is highly lipophilic and extensively bound to plasma proteins, has a longer half-life, is mainly eliminated in the metabolized state via urine and faeces and does not accumulate in kidney dysfunction. As a result of a more stable pharmacokinetic profile, the incidence of toxic side effects seems to be lower with digitoxin than with digoxin. Since the beginning of the 1990s, the antagonists of the RAAS qualified as the standard treatment for congestive heart failure, often in combination with diuretics, vasodilators or beta-antagonists. However, the important role of digitalis glycosides as therapeutic comedication or alternative was never denied, especially in atrial fibrillation with tachycardia. The PROVED and RADIANCE trials proved a detrimental effect of the withdrawal of digoxin therapy on exercise capacity, left-ventricular ejection fraction and clinical symptoms. The DIG trial revealed that digoxin comedication in sinus rhythm patients with congestive heart failure was associated with a lower morbidity (as taken from death or hospitalization because of worsening heart failure) and an unchanged overall mortality--being a unique feature among the available inotropic drugs. Comparable studies for digitoxin have not yet been performed but, because of its higher pharmacological stability, it might well be associated with even more advantages in this regard than digoxin.
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Affiliation(s)
- G G Belz
- Centre for Cardiovascular Pharmacology, ZeKaPha GmbH, Mainz-Wiesbaden, Germany
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10
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Kirch C, Grossmann M, Fischer S, Neumeister V, Kirch W. Effect of digoxin on circadian blood pressure values in patients with congestive heart failure. Eur J Clin Invest 2000; 30:285-9. [PMID: 10759875 DOI: 10.1046/j.1365-2362.2000.00627.x] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 01/15/2023]
Abstract
BACKGROUND The aim of the study was to investigate the effect of chronic digoxin treatment on circadian blood pressure profile in normotensive patients with mild congestive heart failure. METHODS In a randomized double-blind, placebo-controlled cross-over protocol, 12 normotensive patients with mild congestive heart failure took digoxin or placebo for a total of 7 days. Automatic 24-h ambulatory blood pressure measurements were carried out at day 7, of either digoxin or placebo. RESULTS Diastolic blood pressure significantly decreased and systolic blood pressure significantly increased during overnight sleep in the digoxin phase compared to placebo. Digoxin had no effect on either systolic or diastolic blood pressure during daytime. Heart rate decreased in the overnight sleeping phase but did not differ significantly between placebo and digoxin phase. CONCLUSIONS Digoxin significantly decreases diastolic blood pressure during overnight sleep in patients with congestive heart failure. This effect is likely to be caused by reduction of sympathetic activity or increase of parasympathetic activity. Increase of systolic blood pressure during sleep is probably caused by the positive inotropic effect of the drug.
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Affiliation(s)
- C Kirch
- Faculty of Medicine, University of Technology, Dresden, Germany
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11
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Grossmann M, Jamieson MJ, Kirch W. Effects of digoxin and digitoxin on circadian blood pressure profile in healthy volunteers. Eur J Clin Invest 1998; 28:701-6. [PMID: 9767368 DOI: 10.1046/j.1365-2362.1998.00358.x] [Citation(s) in RCA: 15] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 11/20/2022]
Abstract
BACKGROUND The aim of the study was to investigate the potential effects of chronic digoxin or digitoxin treatment or circadian blood pressure profile in normotensive subjects. METHODS In two randomized double-blind, placebo-controlled cross-over protocols, 22 healthy normotensive subjects were enrolled, 12 subjects in either study. After adequate loading doses, digoxin 0.25 mg twice daily or digitoxin 0.1 mg daily was given for a total of 10 days. Automatic 24-h ambulatory blood pressure measurements were carried out at days 4 and 10 of either glycoside or placebo. RESULTS Digoxin treatment significantly decreased heart rate (HR) and diastolic blood pressure (DBP) during the overnight sleeping phase of day 10 compared with placebo (HR, 4 beats min-1; DBP, 8 mmHg; P < 0.05). Digitoxin treatment significantly decreased heart rate and diastolic blood pressure during the overnight sleeping phase of day 4 (HR, 8 beats min-1; DBP, 7 mmHg) and day 10 (HR, 7 beats min-1; DBP, 5 mmHg) compared with placebo (P < 0.05). Neither digoxin nor digitoxin significantly affected systolic blood pressure. CONCLUSIONS Both digoxin and digitoxin, within therapeutic steady-state plasma concentrations, reduced diastolic blood pressure and heart rate during overnight sleep, presumably because of increased parasympathetic activity or decreased sympathetic activity.
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Affiliation(s)
- M Grossmann
- Institute of Clinical Pharmacology, Faculty of Medicine, Technical University, Dresden, Germany.
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Affiliation(s)
- M Gheorghiade
- Department of Medicine, Northwestern University Medical School, Chicago, Ill. 60611, USA
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13
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Gheorghiade M, Hall VB, Jacobsen G, Alam M, Rosman H, Goldstein S. Effects of increasing maintenance dose of digoxin on left ventricular function and neurohormones in patients with chronic heart failure treated with diuretics and angiotensin-converting enzyme inhibitors. Circulation 1995; 92:1801-7. [PMID: 7671364 DOI: 10.1161/01.cir.92.7.1801] [Citation(s) in RCA: 124] [Impact Index Per Article: 4.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 01/26/2023]
Abstract
BACKGROUND Despite almost three centuries of use, the appropriate dosage of digitalis in patients with chronic heart failure and normal sinus rhythm has not been well studied. METHODS AND RESULTS We studied 22 patients with heart failure who were receiving constant daily doses of digoxin, diuretics, and angiotensin-converting enzyme (ACE) inhibitors. In 18 patients, the oral daily dose of digoxin was increased from a mean of 0.20 +/- 0.07 to 0.39 +/- 0.11 mg/day corresponding to an increase in the serum digoxin concentration from 0.67 +/- 0.22 to 1.22 +/- 0.35 ng/mL. Radionuclide and echocardiographic left ventricular ejection fraction; maximal treadmill time; heart failure score; serum concentrations of norepinephrine, aldosterone, atrial natriuretic factor, and antidiuretic hormone; and plasma renin activity were obtained before and after the increase in digoxin dose. Subsequently, 9 patients were randomized to receive digoxin and 9 to receive placebo and radionuclide ejection fraction measured after 12 weeks. With the higher dose of digoxin compared with the lower dose, there was a significant increase in radionuclide ejection fraction from 23.7 +/- 9.6% to 27.1 +/- 11.8% (P = .007). No significant changes were noted in heart failure score; exercise tolerance; serum concentrations of norepinephrine, atrial natriuretic factor, and antidiuretic hormone; and plasma renin activity. There was, however, an increase in serum aldosterone concentration. Twelve weeks after the patients were randomized to receive digoxin or placebo, there was a significant decrease in ejection fraction (from 29.4 +/- 10.4% to 23.7 +/- 8.9%) in the placebo group but not in patients who continued to receive digoxin (P = .002). CONCLUSIONS The increase in maintenance digoxin dose, while maintaining serum concentrations within therapeutic range, resulted in a significant increase in left ventricular ejection fraction that was not associated with significant changes in heart failure score, exercise tolerance, and neurohumoral profile.
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Affiliation(s)
- M Gheorghiade
- Division of Biostatistics, Henry Ford Heart and Vascular Institute, Detroit, Mich, USA
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Cargill RI, Kiely DG, Lipworth BJ. Left ventricular systolic performance during acute hypoxemia. Chest 1995; 108:899-902. [PMID: 7555158 DOI: 10.1378/chest.108.4.899] [Citation(s) in RCA: 18] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/25/2023] Open
Abstract
STUDY OBJECTIVE Although some of the cardiovascular responses to hypoxemia are well described, effects on myocardial contractility have not been defined. Such effects are readily assessed by noninvasive techniques and we have therefore evaluated Doppler-phonocardiographic parameters of systolic left ventricular contractility in normal humans rendered hypoxemic. DESIGN Eight healthy male volunteers were studied. Parameters were measured after resting to achieve baseline haemodynamics, after 20 min moderate hypoxemia (SaO2 85 to 90%), and after a further 20 min of severe hypoxemia (SaO2 75 to 80%). Hypoxemia was induced by breathing a variable N2/O2 mixture. MEASUREMENTS Pulsed-wave Doppler analysis of ascending aortic blood flow was combined with phonocardiography to measure indices of systolic left ventricular function at baseline and at the end of each period of hypoxemia. RESULTS There was a significant, dose-related increase in cardiac output in response to hypoxemia, from 5.5 +/- 0.26 L/min at baseline to 6.1 +/- 0.08 L/min during moderate hypoxemia and to 7.0 +/- 0.23 L/min during severe hypoxemia. Likewise, heart rate increased significantly in dose-related fashion although stroke volume was not affected by either level of hypoxemia. Hypoxemia had no significant effects on systolic or diastolic blood pressures, but caused a significant reduction in systemic vascular resistance. Aortic peak and mean acceleration and acceleration time were not affected by moderate or severe hypoxemia. Although the systolic time intervals measured shortened significantly during severe hypoxemia, these were no longer significant when appropriate corrections were made for heart rate. CONCLUSIONS Although cardiac output increases during hypoxemia, this is due to increases in heart rate but not to any effect on stroke volume. Parameters of left ventricular systolic function and myocardial inotropic state were also not affected by severe hypoxemia. Systolic left ventricular function and myocardial contractility are thus well preserved in normal humans during hypoxemia.
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Affiliation(s)
- R I Cargill
- Department of Clinical Pharmacology, Ninewells Hospital and Medical School, University of Dundee, Scotland
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16
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Affiliation(s)
- Q Li
- Zentrum für Kardiovaskuläre Pharmakologie, ZeKaPha GmbH, Mainz, Germany
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de Mey C, Elich D, Schroeter V, Butzer R, Belz GG. Captopril does not interact with the pharmacodynamics and pharmacokinetics of digitoxin in healthy man. Eur J Clin Pharmacol 1992; 43:445-7. [PMID: 1451730 DOI: 10.1007/bf02220626] [Citation(s) in RCA: 10] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/27/2022]
Abstract
The chronic oral administration of 0.07 mg digitoxin o.d. for up to 58 days to 12 healthy volunteers caused a small drop in mean heart rate HR (95% CI: -7.9 to -1.6 beats.min-1), in mean diastolic blood pressure (95% CI: -8.3 to -0.4 mmHg), shortening of the QTc-interval (95% CI: -42 to -19 ms), shortening of the HR-corrected pre-ejection period PEPc (95% CI: -16 to -1 ms) and electromechanical systole QS2c (95% CI: -25 to -1 ms), and an increase in the impedance cardiographic Heather index (dZ/dtmax/RZ, 95% CI: 0.3 to 4.3) relative to the baseline measurements before digitalisation. The concomitant administration of 25 mg oral captopril b.d. did not significantly alter these responses relative to the concomitant double-blind administration of placebo, nor did it alter the pharmacokinetic characteristics of plasma digitoxin at steady state. Thus, no relevant change in the pharmacokinetic and pharmacodynamic characteristics of chronically administered digitoxin were induced by concomitant treatment with captopril.
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Affiliation(s)
- C de Mey
- Center for Cardiovascular Pharmacology, Mainz, FRG
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18
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Abstract
The development of the radioimmunoassay for digoxin by Smith and coworkers in 1969 was a landmark in digitalis therapy. Since then, the complex pharmacokinetics of digoxin have been defined. As a result, the incidence of digitalis toxicity has markedly decreased. To use the digoxin assay properly, however, the relation of this pharmacokinetic parameter to digoxin pharmacodynamics must be known and the limitations of the assay itself understood. Systolic time intervals (STI) are uniquely useful to quantitate the inotropic effect of digitalis preparations. This technique can demonstrate the onset and magnitude of the inotropic effect for both oral and intravenous digitalis administration. By defining the mathematical relation between STI and simultaneous serum digoxin concentrations following intravenous administration of 1 mg digoxin, computer simulations can be made of the effect of dosing changes on blood and tissue concentrations. The serum digoxin assay has technical problems relating to quality control, interference by metabolites, and cross-reactions with endogenous digitalis-like substances. Further, a standard time for measurement following dosing has not been established. Physical activity can significantly after the serum digoxin concentrations by increasing skeletal muscle binding. Numerous drugs can interfere with digoxin absorption or elimination. Using the serum digoxin assay is the only way to assess these interactions. Computer surveillance (ideally with physician or pharmacist interaction) has been used to monitor digitalis but has not yet gained widespread acceptance. This is clearly a method in need of further testing.
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Affiliation(s)
- R P Lewis
- Division of Cardiology, Ohio State University, Columbus 43210
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THOMAS RICHARD, GRAY PETER, ANDREWS JOANNE. Digitalis: Its Mode of Action, Receptor, and Structure–Activity Relationships. ACTA ACUST UNITED AC 1990. [DOI: 10.1016/b978-0-12-013319-2.50009-7] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 03/08/2023]
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Affiliation(s)
- W Kirch
- I. Medizinische Klinik, Christian-Albrechts-Universität, Kiel, F.R.G
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Belz GG, Meinicke T, Schäfer-Korting M. The relationship between pharmacokinetics and pharmacodynamics of enoximone in healthy man. Eur J Clin Pharmacol 1988; 35:631-5. [PMID: 2976670 DOI: 10.1007/bf00637599] [Citation(s) in RCA: 11] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/03/2023]
Abstract
The relationship between the pharmacokinetics and pharmacodynamics of enoximone, a new positive inotropic agent, was investigated in 6 healthy men. The volunteers received single oral and i.v. doses of 3 and 1 mg/kg, respectively, and placebo in a double-blind cross-over trial. Plasma concentrations of enoximone and its sulphoxide metabolite, effects on the corrected electromechanical systole (QS2c), the impedance cardiogram (dZ/dt)/RZ index, blood pressure and heart rate were determined over an 8-h period. Peak effects on QS2c and the (dZ/dt)/RZ index were obtained after approximately 1 h. During the first hour, the cardiac effects lagged behind the high plasma concentrations. Thereafter, the effects on QS2c were closely correlated with the plasma concentrations both of enoximone and its sulphoxide derivative (r greater than or equal to 0.90). The concentration-effect curves of both substances were parallel and were independent of the route of administration. The inotropic activity was not related to the drug level in hypothetical peripheral compartments. The results suggest that determination of plasma enoximone 1 h after administration and thereafter may be useful in assessing the haemodynamic activity of the drug. Should this observation also be present in a clinical situation, plasma enoximone measurement might be a valuable tool in management of patients suffering from heart failure.
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Affiliation(s)
- G G Belz
- Zentrum für kardiovaskuläre Pharmakologie, ZeKaPha, Wiesbaden, Federal Republic of Germany
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Gortner L, Hellenbrecht D. Estimation of digoxin dosage in VLBW infants using serum creatinine concentrations. ACTA PAEDIATRICA SCANDINAVICA 1986; 75:433-8. [PMID: 3728003 DOI: 10.1111/j.1651-2227.1986.tb10226.x] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 01/07/2023]
Abstract
Digoxin steady state plasma concentrations (Css) and the corresponding serum creatinine concentrations were studied in 17 VLBW infants. Birth weight was in the range of 760-1 500 g (mean 1 068 g), gestational age ranged from 26 to 32 weeks (mean 28.7 weeks). Digoxin steady state plasma concentrations were found in the range of 0.5-6.5 ng/ml (mean 1.88 ng/ml) during maintenance therapy with 1.6-8.4 micrograms/kg BW/24 h (mean 4.4 micrograms/kg BW/24 h) given in two divided doses intravenously. No digoxin-like immunoreactive substance could be detected in the plasma of 18 infants (10 patients with a birth weight less than or equal to 1 500 g, 8 patients with a birth weight of 2 100-4 730 g) that were not treated with digoxin. The calculated digoxin clearance ranged from 0.38-4.03 ml/min/kg BW. Serum creatinine concentrations were found in the range of 35-274 mumol/l (0.4-3.1 mg/100 ml). A hyperbolic correlation may be derived from the digoxin clearance and the corresponding serum creatinine concentration. A linear relationship was observed between the dose normalized digoxin concentrations (y = Css/dose in 24 h) and the respective creatinine concentrations x (y = 0.52x-0.05; n = 17; s = 0.24; r = 0.86; p less than 0.01). According to this equation we suggest a dosing schedule for digoxin in VLBW infants with impaired renal function. Digoxin maintenance dose is derived from the digoxin target and the creatinine serum concentration. This dose recommendation proved reliable on four VLBW infants (birth weight 770-1 260 g) with decreased renal function.
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Cook LS, Elkins RC, Doherty JE. Cardiovascular effects of atropine in postoperative cardiac patients receiving digoxin for ventricular dysfunction. Am Heart J 1986; 111:80-4. [PMID: 3946163 DOI: 10.1016/0002-8703(86)90556-9] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 01/08/2023]
Abstract
Digoxin is clinically useful as a cardiac antiarrhythmic and inotropic agent. Its antiarrhythmic actions are mediated through the cholinergic nervous system. The cholinergic system, when activated, can depress ventricular function. We have sought to further increase the cardiovascular effects of digoxin by blocking its cholinergic effects with atropine. Atropine, 1 mg intravenously, was given to 10 postoperative cardiac patients. The cardiovascular time course was monitored by an ECG, radial arterial line, and pulmonary artery thermodilution catheter for 8 hours. A significant increase (p less than 0.05) in the cardiac output (CO), from 5.98 +/- 0.24 L/min to 6.60 +/- 0.34 L/min, was evident within 2 hours after atropine administration. The CO returned to control levels by 6 hours. There were no significant changes in heart rate, systemic vascular resistance, pulmonary artery wedge pressure, or systemic blood pressure. The results indicate that the cholinergic blockade of digoxin with atropine will acutely increase the cardiac output in postoperative cardiac patients.
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Ware JA, Snow E, Luchi JM, Luchi RJ. Effect of digoxin on ejection fraction in elderly patients with congestive heart failure. J Am Geriatr Soc 1984; 32:631-5. [PMID: 6236251 DOI: 10.1111/j.1532-5415.1984.tb02249.x] [Citation(s) in RCA: 36] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/19/2023]
Abstract
To assess the effect of oral digoxin on left ventricular systolic function in elderly patients, radionuclide angiography was performed on 20 patients 74 years old or older before and after several weeks of oral digoxin. The mean age was 83.8 years. All had congestive heart failure or cardiomegaly, and all were in sinus rhythm. The ejection fraction was 0.36 +/- 0.10 (mean +/- SD) before digoxin; 0.45 +/- 0.09 after digoxin (P less than 0.01). A comparison group that did not receive digoxin had no significant improvement in ejection fraction. In ten patients serial radionuclide angiograms were repeated after increasing serum digoxin concentrations. Six demonstrated maximal improvement in ejection fraction at serum digoxin concentrations of 0.4-1.0 ng/ml. It is concluded that oral digoxin improves left ventricular ejection fraction in elderly patients with congestive heart failure or cardiomegaly who are in sinus rhythm. Some of these patients achieve maximal improvement in ejection fraction at serum digoxin concentrations of less than 1.0 ng/ml.
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Smith TW, Antman EM, Friedman PL, Blatt CM, Marsh JD. Digitalis glycosides: mechanisms and manifestations of toxicity. Part III. Prog Cardiovasc Dis 1984; 27:21-56. [PMID: 6146162 DOI: 10.1016/0033-0620(84)90018-5] [Citation(s) in RCA: 62] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 01/18/2023]
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Smith TW, Antman EM, Friedman PL, Blatt CM, Marsh JD. Digitalis glycosides: mechanisms and manifestations of toxicity. Part II. Prog Cardiovasc Dis 1984; 26:495-540. [PMID: 6326196 DOI: 10.1016/0033-0620(84)90014-8] [Citation(s) in RCA: 64] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 01/19/2023]
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Smith TW, Antman EM, Friedman PL, Blatt CM, Marsh JD. Digitalis glycosides: mechanisms and manifestations of toxicity. Part I. Prog Cardiovasc Dis 1984; 26:413-58. [PMID: 6371896 DOI: 10.1016/0033-0620(84)90012-4] [Citation(s) in RCA: 94] [Impact Index Per Article: 2.4] [Reference Citation Analysis] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 01/19/2023]
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Belz GG, Matthews J, Sauer U, Stern H, Schneider B. Pharmacodynamic effects of ouabain following single sublingual and intravenous doses in normal subjects. Eur J Clin Pharmacol 1984; 26:287-92. [PMID: 6428911 DOI: 10.1007/bf00548756] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/20/2023]
Abstract
In this intraindividual, placebo-controlled, double blind study the dynamic effects of single doses of ouabain 0.5 mg i.v. and 12 mg sublingual were compared with those of the vasodilator sublingual nitroglycerin 0.8 mg. In 12 (sublingual) and 6 (i.v.) healthy volunteers, respectively, cardiac performance was assessed for 60 min after administration, using systolic time intervals ( QS2c , PEPc, PEP/LVET), electrical impedance cardiography ( (dZ/dt)/RZ index) and echocardiography (EDD, ESD, FS). After i.v. ouabain the typical positive inotropic glycoside effects appeared (shortening of QS2c , PEPc, and PEP/LVET, increase of (dZ/dt)/RZ and FS, decrease of EDD and ESD). With nitroglycerin preload reduction diminished cardiac performance, as shown by a rise in PEPc and PEP/LVET and depression of (dZ/dt)/RZ. In addition, EDD (not significant) and ESD were somewhat reduced, FS was enhanced, and QS2c tended to shorten. Following sublingual ouabain, QS2c was unchanged, there was an increase in PEPc and PEP/LVET, a decrease in (dZ/dt)/RZ and FS, EDD was unchanged, and ESD rose. By this route the absolute magnitude of the effects was about 1/3 that of the i.v. drug action. The spectrum of effects of sublingual ouabain indicates a reduction in cardiac performance without any detectable inotropic action. The effects seem to be induced by load changes, with an indication of an increase in afterload although an additional preload reduction cannot be excluded. This dose of the drug given by the sublingual route appears, therefore, to alter cardiac function via an effect on the peripheral circulation, although the final mechanism has not yet been elucidated.(ABSTRACT TRUNCATED AT 250 WORDS)
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Abstract
The narrow therapeutic range of cardiac glycosides continually challenges chemists to synthetize new derivatives with improved therapeutic properties. One of the best investigated semi-synthetic glycosides is 16 alpha-gitoxin. Compared to ouabain and gitoxin, it produces positive inotropic effects on the isolated guinea-pig heart in a wider range of concentrations and causes less pronounced rhythmic disturbances. These results were confirmed by electrophysiological investigations in isolated fibres of the canine myocardium and of the Purkinje system, by investigations in the anaesthetized cat and dog and in healthy volunteers. The effects of various semi-synthetic compounds (e.g. actodigin, ASI-222) are described and possibilities to trigger these effects are discussed. Of some significance seem to be differences in the structure of the (Na+ + K+)-ATPase system of different tissues, e.g. the working muscle and the Purkinje system of the heart, as well as differences due to the formation and dissociation of the glycoside-enzyme complex. The significance of K+, Ca2+ and of several pharmacokinetic parameters (e.g. the volume of distribution) for these reactions are briefly discussed.
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Coates AL, Desmond K, Asher MI, Hortop J, Beaudry PH. The effect of digoxin on exercise capacity and exercising cardiac function in cystic fibrosis. Chest 1982; 82:543-7. [PMID: 7128221 DOI: 10.1378/chest.82.5.543] [Citation(s) in RCA: 20] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/23/2023] Open
Abstract
The ability of digoxin to increase exercise capacity and stroke volume (SV) during exercise was evaluated in ten patients with cystic fibrosis (CF) ages 12 to 20 years with moderate to severe degrees of airway obstruction but no history of heart failure. A double-blind crossover trial of digoxin versus placebo was carried out. An evaluation of exercise performance was undertaken upon entry into the study, and after each of the one-week periods in which digoxin 0.25 mg/day or placebo was taken. Exercise testing consisted of a progressive exercise test on a cycle ergometer to measure maximum work capacity (Wmax) and a steady state test at 2/3 of the baseline Wmax. During the steady state test, the oxygen consumption and carbon dioxide production were measured and cardiac output (Q) was calculated by the indirect Fick (CO2) method. From Q and heart rate (HR), SV was derived. After digoxin, Wmax was unchanged. On steady state exercise HR was unchanged, but there was a slight but significant fall in Q due to a fall in SV. The decrease in SV was associated with exercising hypoxemia. We conclude that digoxin did not increase exercise capacity or improve exercising cardiac function in patients with moderate to severe airway obstruction due to CF.
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Belz GG, Aust PE, Doering W, Heinz M, Schneider B. Pharmacodynamics of a single dose of quinidine during chronic digoxin treatment. A randomized double blind placebo and sparteine--controlled crossover study. Eur J Clin Pharmacol 1982; 22:117-22. [PMID: 7094981 DOI: 10.1007/bf00542455] [Citation(s) in RCA: 14] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/23/2023]
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Abstract
To judge the influence of drugs and diseases on systolic time intervals (STI), the connection to the covariate belonging to heart frequency has to be eliminated. For this purpose, we adopt linear dependency of the interval between the R-waves in the ECG and STI. In this paper, according to different medical questions, well-fitting correction formulae are derived, based on new biometric analysis of published data. The methods used include L1-norm and L2-norm regression, rank-test connected regression Theil and Sen, and rank-scores analysis of covariance. It is concluded that the biometric methods must be well adapted to medical methods.
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Sheiner LB, Benet LZ, Pagliaro LA. A standard approach to compiling clinical pharmacokinetic data. JOURNAL OF PHARMACOKINETICS AND BIOPHARMACEUTICS 1981; 9:59-127. [PMID: 7014827 DOI: 10.1007/bf01059343] [Citation(s) in RCA: 25] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 01/23/2023]
Abstract
A standard format for a Clinical Pharmacokinetic Summary is proposed. It consists of a heading, tables, notes, and references for each drug reviewed. The table presents a unified and logical set of clinically useful population pharmacokinetic parameters. They concern four major areas: absorption, distribution, elimination, and the relationship of concentration to effect. Within each major group, parameters dealing with extents and rates of processes are given. Each such parameter is really two: a population mea value (for example, average volume of distribution) and the standard deviation of individual values about this mean. The first value allows individual predictions of dosage or drug level to be made; the second allows computation of the likely proximity of subsequently observed quantities to those predictions. The table presents single consensus values for each population parameter, rather than a list of values. A procedure for computing these consensus values, and for revising them in the light of new data, or reinterpreted old data, is given. Examples of Summaries are given. The method appears applicable to a variety of drugs. We suggest our approach as a standard one for preparing Clinical Pharmacokinetic Summaries, and urge our colleagues to consider it for that purpose.
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Jogestrand T, Sundqvist K. Skeletal muscle digoxin concentration and its relation to serum digoxin concentration and cardiac effect in healthy man. Eur J Clin Pharmacol 1981; 19:89-95. [PMID: 7202476 DOI: 10.1007/bf00568394] [Citation(s) in RCA: 24] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/24/2023]
Abstract
Blood samples and skeletal muscle biopsies (m. quadriceps femoris, vastus lateralis) were taken from seven healthy subjects for analysis of serum and skeletal muscle digoxin concentrations by radioimmunoassay using a percutaneous needle biopsy technique for muscle sampling. The subjects were investigated on two digoxin dose levels and on the third day after withdrawal of digoxin. It was found that the skeletal muscle/serum digoxin ratio was significantly higher than the corresponding ratio obtained in a previous study with muscle sampling (m. rectus abdominis) from patients during open heart surgery. The present study indicates a significant correlation between the digoxin concentrations in serum and skeletal muscle as well as between cardiac effect, measured by changes in QS2I, and skeletal muscle digoxin concentration. A doubling of the digoxin dose gave a proportional increase in skeletal muscle digoxin concentration. The magnitude of the estimated half-life of skeletal muscle digoxin was the same as previously reported for serum or plasma digoxin.
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Jogestrand T, Ericsson F, Sundqvist K. Skeletal muscle digoxin concentration during digitalization and during withdrawal of digoxin treatment. Eur J Clin Pharmacol 1981; 19:97-105. [PMID: 7202477 DOI: 10.1007/bf00568395] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/24/2023]
Abstract
Blood samples and skeletal muscle biopsies (m. quadriceps femoris, vastus lateralis) were taken from 15 patients during digitalization or during withdrawal of digoxin treatment for analysis of serum and skeletal muscle digoxin concentrations. A percutaneous needle biopsy technique was used for muscle sampling and digoxin was analysed by radioimmunoassay. During "slow" digitalization with 0.25 mg digoxin daily the skeletal muscle digoxin concentrations after 2 and 4 days were 45% (range 19%--62%; n = 3) and 78% (range 56%--92%; n= 3) respectively, of the steady state concentration (defined as the digoxin concentration after 25--40 days of treatment). After 9 and 11 days of treatment the skeletal muscle digoxin concentrations were 106% (range 84%--133%; n = 5) and 116% (range 72%--164%; n = 3) respectively, of the steady state concentration. A doubling of the digoxin dose gave a proportional increase in skeletal muscle digoxin concentration (three patients). The magnitude of the estimated half-life of skeletal muscle digoxin was the same as previously reportedly in healthy subjects. No significant correlations were found between changes in systolic time intervals and steady state serum or skeletal muscle digoxin concentrations.
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Joubert P, Belz GG. Relationship between inotropic changes and ECG changes induced by digitalis. Eur J Clin Pharmacol 1979; 15:447-8. [PMID: 499294 DOI: 10.1007/bf00561746] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.0] [Reference Citation Analysis] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/15/2022]
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