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Roth HR, Reinert JP. Methylxanthine Derivatives in the Treatment of Sinus Node Dysfunction: A Systematic Review. Cardiol Rev 2023:00045415-990000000-00159. [PMID: 37909739 DOI: 10.1097/crd.0000000000000609] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 11/03/2023]
Abstract
While the chronotropic effects of theophylline and aminophylline are well-known, their clinical application in the treatment of sinus node dysfunction has not been established in a review. The purpose of this systematic review is to evaluate the efficacy and safety of methylxanthines in the treatment of bradyarrhythmias associated with sinus node dysfunction. A systematic review was conducted in accordance with PRISMA guidelines on Embase, PubMed, MEDLINE, Cochrane Central, Web of Science, SciELO, Korean Citation Index, Global Index Medicus, and CINAHL through June 2023. A total of 607 studies were identified through the literature search. After applying the inclusion and exclusion criteria, 14 studies were included in this review. The causes of bradyarrhythmias involving the sinoatrial node included acute cervical spinal cord injury, coronavirus disease of 2019, carotid sinus syncope, chronotropic incompetence, heart transplant, and chronic sinus node dysfunction. Theophylline and aminophylline were shown to be effective for increasing heart rate and reducing the reoccurrence of bradyarrhythmias. The data on symptom resolution was conflicting. While many case studies reported a resolution of symptoms, a randomized controlled trial reported no significant difference in symptom scores between the control, theophylline, and pacemaker groups in the treatment of sick sinus syndrome. The incidence of adverse effects was low across all study designs. The data suggests methylxanthines may be useful as an alternative or bridge to nonpharmacologic pacing; however, dosing has yet to be established for various indications. Overall, methylxanthines proved safe and effective as a pharmacologic therapy for bradyarrhythmic manifestations of sinus node dysfunction.
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Affiliation(s)
- Hunter R Roth
- From the Department of Pharmacy Practice, The University of Toledo College of Pharmacy and Pharmaceutical Sciences, Toledo, OH
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2
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Amir R, Vakil RM, Stevenson WG, Tandri H. Oral theophylline for treatment of painful left bundle branch block. HeartRhythm Case Rep 2023; 9:342-346. [PMID: 37361985 PMCID: PMC10285126 DOI: 10.1016/j.hrcr.2023.02.017] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 06/28/2023] Open
Affiliation(s)
- Rawan Amir
- Division of Cardiology, Department of Medicine, Johns Hopkins University School of Medicine, Baltimore, Maryland
| | - Rachit M. Vakil
- Division of Cardiology, Department of Medicine, Johns Hopkins University School of Medicine, Baltimore, Maryland
| | - William G. Stevenson
- Division of Cardiology, Department of Medicine, Vanderbilt University Medical Center, Nashville, Tennessee
| | - Harikrishna Tandri
- Division of Cardiology, Department of Medicine, Vanderbilt University Medical Center, Nashville, Tennessee
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3
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Manoj P, Kim JA, Kim S, Li T, Sewani M, Chelu MG, Li N. Sinus node dysfunction: current understanding and future directions. Am J Physiol Heart Circ Physiol 2023; 324:H259-H278. [PMID: 36563014 PMCID: PMC9886352 DOI: 10.1152/ajpheart.00618.2022] [Citation(s) in RCA: 4] [Impact Index Per Article: 4.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 11/01/2022] [Revised: 12/20/2022] [Accepted: 12/21/2022] [Indexed: 12/24/2022]
Abstract
The sinoatrial node (SAN) is the primary pacemaker of the heart. Normal SAN function is crucial in maintaining proper cardiac rhythm and contraction. Sinus node dysfunction (SND) is due to abnormalities within the SAN, which can affect the heartbeat frequency, regularity, and the propagation of electrical pulses through the cardiac conduction system. As a result, SND often increases the risk of cardiac arrhythmias. SND is most commonly seen as a disease of the elderly given the role of degenerative fibrosis as well as other age-dependent changes in its pathogenesis. Despite the prevalence of SND, current treatment is limited to pacemaker implantation, which is associated with substantial medical costs and complications. Emerging evidence has identified various genetic abnormalities that can cause SND, shedding light on the molecular underpinnings of SND. Identification of these molecular mechanisms and pathways implicated in the pathogenesis of SND is hoped to identify novel therapeutic targets for the development of more effective therapies for this disease. In this review article, we examine the anatomy of the SAN and the pathophysiology and epidemiology of SND. We then discuss in detail the most common genetic mutations correlated with SND and provide our perspectives on future research and therapeutic opportunities in this field.
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Affiliation(s)
- Pavan Manoj
- School of Public Health, Texas A&M University, College Station, Texas
| | - Jitae A Kim
- Department of Medicine, Baylor College of Medicine, Houston, Texas
| | - Stephanie Kim
- Department of BioSciences, Rice University, Houston, Texas
| | - Tingting Li
- Section of Cardiovascular Research, Department of Medicine, Baylor College of Medicine, Houston, Texas
| | - Maham Sewani
- Department of BioSciences, Rice University, Houston, Texas
| | - Mihail G Chelu
- Division of Cardiology, Department of Medicine, Baylor College of Medicine, Houston, Texas
| | - Na Li
- Section of Cardiovascular Research, Department of Medicine, Baylor College of Medicine, Houston, Texas
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4
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Ono K, Iwasaki YK, Akao M, Ikeda T, Ishii K, Inden Y, Kusano K, Kobayashi Y, Koretsune Y, Sasano T, Sumitomo N, Takahashi N, Niwano S, Hagiwara N, Hisatome I, Furukawa T, Honjo H, Maruyama T, Murakawa Y, Yasaka M, Watanabe E, Aiba T, Amino M, Itoh H, Ogawa H, Okumura Y, Aoki-Kamiya C, Kishihara J, Kodani E, Komatsu T, Sakamoto Y, Satomi K, Shiga T, Shinohara T, Suzuki A, Suzuki S, Sekiguchi Y, Nagase S, Hayami N, Harada M, Fujino T, Makiyama T, Maruyama M, Miake J, Muraji S, Murata H, Morita N, Yokoshiki H, Yoshioka K, Yodogawa K, Inoue H, Okumura K, Kimura T, Tsutsui H, Shimizu W. JCS/JHRS 2020 Guideline on Pharmacotherapy of Cardiac Arrhythmias. Circ J 2022; 86:1790-1924. [DOI: 10.1253/circj.cj-20-1212] [Citation(s) in RCA: 13] [Impact Index Per Article: 6.5] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 12/19/2022]
Affiliation(s)
| | - Yu-ki Iwasaki
- Department of Cardiovascular Medicine, Nippon Medical School
| | - Masaharu Akao
- Department of Cardiovascular Medicine, National Hospital Organization Kyoto Medical Center
| | - Takanori Ikeda
- Department of Cardiovascular Medicine, Toho University Graduate School of Medicine
| | - Kuniaki Ishii
- Department of Pharmacology, Yamagata University Faculty of Medicine
| | - Yasuya Inden
- Department of Cardiology, Nagoya University Graduate School of Medicine
| | - Kengo Kusano
- Department of Cardiovascular Medicine, National Cerebral and Cardiovascular Center
| | - Yoshinori Kobayashi
- Division of Cardiology, Department of Medicine, Tokai University Hachioji Hospital
| | | | - Tetsuo Sasano
- Department of Cardiovascular Medicine, Tokyo Medical and Dental University
| | - Naokata Sumitomo
- Department of Pediatric Cardiology, Saitama Medical University International Medical Center
| | - Naohiko Takahashi
- Department of Cardiology and Clinical Examination, Faculty of Medicine, Oita University
| | - Shinichi Niwano
- Department of Cardiovascular Medicine, Kitasato University School of Medicine
| | | | | | - Tetsushi Furukawa
- Department of Bio-information Pharmacology, Medical Research Institute, Tokyo Medical and Dental University
| | - Haruo Honjo
- Research Institute of Environmental Medicine, Nagoya University
| | - Toru Maruyama
- Department of Hematology, Oncology and Cardiovascular Medicine, Kyushu University Hospital
| | - Yuji Murakawa
- The 4th Department of Internal Medicine, Teikyo University School of Medicine, Mizonokuchi Hospital
| | - Masahiro Yasaka
- Department of Cerebrovascular Medicine and Neurology, Clinical Research Institute, National Hospital Organization Kyushu Medical Center
| | - Eiichi Watanabe
- Department of Cardiology, Fujita Health University School of Medicine
| | - Takeshi Aiba
- Department of Cardiovascular Medicine, National Cerebral and Cardiovascular Center
| | - Mari Amino
- Department of Cardiovascular Medicine, Tokai University School of Medicine
| | - Hideki Itoh
- Division of Patient Safety, Hiroshima University Hospital
| | - Hisashi Ogawa
- Department of Cardiology, National Hospital Organisation Kyoto Medical Center
| | - Yasuo Okumura
- Division of Cardiology, Department of Medicine, Nihon University School of Medicine
| | - Chizuko Aoki-Kamiya
- Department of Obstetrics and Gynecology, National Cerebral and Cardiovascular Center
| | - Jun Kishihara
- Department of Cardiovascular Medicine, Kitasato University School of Medicine
| | - Eitaro Kodani
- Department of Cardiovascular Medicine, Nippon Medical School Tama Nagayama Hospital
| | - Takashi Komatsu
- Division of Cardiology, Department of Internal Medicine, Iwate Medical University School of Medicine
| | | | | | - Tsuyoshi Shiga
- Department of Clinical Pharmacology and Therapeutics, The Jikei University School of Medicine
| | - Tetsuji Shinohara
- Department of Cardiology and Clinical Examination, Faculty of Medicine, Oita University
| | - Atsushi Suzuki
- Department of Cardiology, Tokyo Women's Medical University
| | - Shinya Suzuki
- Department of Cardiovascular Medicine, The Cardiovascular Institute
| | - Yukio Sekiguchi
- Department of Cardiology, National Hospital Organization Kasumigaura Medical Center
| | - Satoshi Nagase
- Department of Cardiovascular Medicine, National Cerebral and Cardiovascular Center
| | - Noriyuki Hayami
- Department of Fourth Internal Medicine, Teikyo University Mizonokuchi Hospital
| | | | - Tadashi Fujino
- Department of Cardiovascular Medicine, Toho University, Faculty of Medicine
| | - Takeru Makiyama
- Department of Cardiovascular Medicine, Graduate School of Medicine, Kyoto University
| | - Mitsunori Maruyama
- Department of Cardiovascular Medicine, Nippon Medical School Musashi Kosugi Hospital
| | - Junichiro Miake
- Department of Pharmacology, Tottori University Faculty of Medicine
| | - Shota Muraji
- Department of Pediatric Cardiology, Saitama Medical University International Medical Center
| | | | - Norishige Morita
- Division of Cardiology, Department of Medicine, Tokai University Hachioji Hospital
| | - Hisashi Yokoshiki
- Department of Cardiovascular Medicine, Sapporo City General Hospital
| | - Koichiro Yoshioka
- Division of Cardiology, Department of Internal Medicine, Tokai University School of Medicine
| | - Kenji Yodogawa
- Department of Cardiovascular Medicine, Nippon Medical School
| | | | - Ken Okumura
- Division of Cardiology, Saiseikai Kumamoto Hospital Cardiovascular Center
| | - Takeshi Kimura
- Department of Cardiovascular Medicine, Graduate School of Medicine, Kyoto University
| | - Hiroyuki Tsutsui
- Department of Cardiovascular Medicine, Faculty of Medical Sciences, Kyushu University
| | - Wataru Shimizu
- Department of Cardiovascular Medicine, Nippon Medical School
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5
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Wallace MJ, El Refaey M, Mesirca P, Hund TJ, Mangoni ME, Mohler PJ. Genetic Complexity of Sinoatrial Node Dysfunction. Front Genet 2021; 12:654925. [PMID: 33868385 PMCID: PMC8047474 DOI: 10.3389/fgene.2021.654925] [Citation(s) in RCA: 20] [Impact Index Per Article: 6.7] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/17/2021] [Accepted: 03/01/2021] [Indexed: 12/13/2022] Open
Abstract
The pacemaker cells of the cardiac sinoatrial node (SAN) are essential for normal cardiac automaticity. Dysfunction in cardiac pacemaking results in human sinoatrial node dysfunction (SND). SND more generally occurs in the elderly population and is associated with impaired pacemaker function causing abnormal heart rhythm. Individuals with SND have a variety of symptoms including sinus bradycardia, sinus arrest, SAN block, bradycardia/tachycardia syndrome, and syncope. Importantly, individuals with SND report chronotropic incompetence in response to stress and/or exercise. SND may be genetic or secondary to systemic or cardiovascular conditions. Current management of patients with SND is limited to the relief of arrhythmia symptoms and pacemaker implantation if indicated. Lack of effective therapeutic measures that target the underlying causes of SND renders management of these patients challenging due to its progressive nature and has highlighted a critical need to improve our understanding of its underlying mechanistic basis of SND. This review focuses on current information on the genetics underlying SND, followed by future implications of this knowledge in the management of individuals with SND.
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Affiliation(s)
- Michael J. Wallace
- Frick Center for Heart Failure and Arrhythmia Research, The Ohio State University Wexner Medical Center, Columbus, OH, United States
- Dorothy M. Davis Heart and Lung Research Institute, The Ohio State University Wexner Medical Center, Columbus, OH, United States
- Department of Physiology and Cell Biology, College of Medicine, The Ohio State University Wexner Medical Center, Columbus, OH, United States
| | - Mona El Refaey
- Frick Center for Heart Failure and Arrhythmia Research, The Ohio State University Wexner Medical Center, Columbus, OH, United States
- Dorothy M. Davis Heart and Lung Research Institute, The Ohio State University Wexner Medical Center, Columbus, OH, United States
- Department of Physiology and Cell Biology, College of Medicine, The Ohio State University Wexner Medical Center, Columbus, OH, United States
| | - Pietro Mesirca
- CNRS, INSERM, Institut de Génomique Fonctionnelle, Université de Montpellier, Montpellier, France
- Laboratory of Excellence ICST, Montpellier, France
| | - Thomas J. Hund
- Frick Center for Heart Failure and Arrhythmia Research, The Ohio State University Wexner Medical Center, Columbus, OH, United States
- Dorothy M. Davis Heart and Lung Research Institute, The Ohio State University Wexner Medical Center, Columbus, OH, United States
- Department of Biomedical Engineering, College of Engineering, The Ohio State University, Columbus, OH, United States
| | - Matteo E. Mangoni
- CNRS, INSERM, Institut de Génomique Fonctionnelle, Université de Montpellier, Montpellier, France
- Laboratory of Excellence ICST, Montpellier, France
| | - Peter J. Mohler
- Frick Center for Heart Failure and Arrhythmia Research, The Ohio State University Wexner Medical Center, Columbus, OH, United States
- Dorothy M. Davis Heart and Lung Research Institute, The Ohio State University Wexner Medical Center, Columbus, OH, United States
- Department of Physiology and Cell Biology, College of Medicine, The Ohio State University Wexner Medical Center, Columbus, OH, United States
- Division of Cardiovascular Medicine, Department of Internal Medicine, College of Medicine, The Ohio State University Wexner Medical Center, Columbus, OH, United States
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6
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Rozenbaum Z, Ben-Gal Y, Kapusta L, Hochstadt A, Sadeh Md B, Aviram Md G, Havakuk Md O, Shimiaie Md J, Ghermezi Md M, Laufer-Perl Md M, Shacham Md Y, Keren G, Topilsky Y. Combined Echocardiographic and Cardiopulmonary Exercise to Assess Determinants of Exercise Limitation in Chronic Obstructive Pulmonary Disease. J Am Soc Echocardiogr 2020; 34:146-155.e5. [PMID: 33187814 DOI: 10.1016/j.echo.2020.09.014] [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] [Received: 03/07/2020] [Revised: 09/08/2020] [Accepted: 09/10/2020] [Indexed: 10/23/2022]
Abstract
BACKGROUND Current methods do not allow a thorough assessment of causes associated with limited exercise capacity in patients with chronic obstructive pulmonary disease (COPD). METHODS Twenty patients with COPD and 20 matched control subjects were assessed using combined cardiopulmonary and stress echocardiographic testing. Various echocardiographic parameters (left ventricular [LV] volumes, right ventricular [RV] area, ejection fraction, stroke volume, S', and E/e' ratio) and ventilatory parameters (peak oxygen consumption [Vo2] and A-Vo2 difference) were measured to evaluate LV and RV function, hemodynamics, and peripheral oxygen extraction (A-VO2 difference). RESULTS Significant differences (both between groups and for group-by-time interaction) were seen in exercise responses (LV volume, RV area, LV volume/RV area ratio, S', E/e' ratio, tricuspid regurgitation grade, heart rate, stroke volume, and Vo2). The major mechanisms of reduced exercise tolerance in patients with COPD were bowing of the septum to the left in 12 (60%), abnormal increases in E/e' ratio in 12 (60%), abnormal stroke volume reserve in 16 (80%), low peak A-Vo2 difference in 10 (50%), chronotropic incompetence in 13 (65%), or a combination of several mechanisms. Patients with COPD and poor exercise tolerance showed attenuated increases in stroke volume, heart rate, and A-Vo2 difference and exaggerated changes in LV/RV ratio and LV compliance (ratio of LV volume to E/e' ratio) compared with patients with COPD with good exercise tolerance. CONCLUSIONS Combined cardiopulmonary and stress echocardiographic testing can be helpful in determining individual mechanisms of exercise intolerance in patients with COPD. In patients with COPD, exercise intolerance is predominantly the result of chronotropic incompetence, limited stroke volume reserve, exercise-induced elevation in left filling pressure, and peripheral factors and not simply obstructive lung function. Limited stroke volume is related to abnormal RV contractile reserve and reduced LV compliance introduced through septal flattening and direct ventricular interaction.
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Affiliation(s)
- Zach Rozenbaum
- Sackler Faculty of Medicine, Cardiology Division, Tel Aviv Sourasky Medical Center, Tel Aviv, Israel
| | - Yanai Ben-Gal
- Sackler Faculty of Medicine, Cardiac Surgery Division, Tel Aviv Sourasky Medical Center, Tel Aviv, Israel
| | - Livia Kapusta
- Department of Paediatrics, Paediatric Cardiology Unit, Tel Aviv Sourasky Medical Centre and Sackler School of Medicine, Tel Aviv University, Tel Aviv, Israel; Department of Paediatric Cardiology, Amalia Children's Hospital, Radboud, University Medical Centre, Nijmegen, the Netherlands
| | - Aviram Hochstadt
- Sackler Faculty of Medicine, Cardiology Division, Tel Aviv Sourasky Medical Center, Tel Aviv, Israel
| | - Ben Sadeh Md
- Sackler Faculty of Medicine, Cardiology Division, Tel Aviv Sourasky Medical Center, Tel Aviv, Israel
| | - Galit Aviram Md
- Sackler Faculty of Medicine, Cardiology Division, Tel Aviv Sourasky Medical Center, Tel Aviv, Israel
| | - Ofer Havakuk Md
- Sackler Faculty of Medicine, Cardiology Division, Tel Aviv Sourasky Medical Center, Tel Aviv, Israel
| | - Jason Shimiaie Md
- Sackler Faculty of Medicine, Cardiology Division, Tel Aviv Sourasky Medical Center, Tel Aviv, Israel
| | - Michael Ghermezi Md
- Sackler Faculty of Medicine, Cardiology Division, Tel Aviv Sourasky Medical Center, Tel Aviv, Israel
| | - Michal Laufer-Perl Md
- Sackler Faculty of Medicine, Cardiology Division, Tel Aviv Sourasky Medical Center, Tel Aviv, Israel
| | - Yacov Shacham Md
- Sackler Faculty of Medicine, Cardiology Division, Tel Aviv Sourasky Medical Center, Tel Aviv, Israel
| | - Gad Keren
- Sackler Faculty of Medicine, Cardiology Division, Tel Aviv Sourasky Medical Center, Tel Aviv, Israel
| | - Yan Topilsky
- Sackler Faculty of Medicine, Cardiology Division, Tel Aviv Sourasky Medical Center, Tel Aviv, Israel.
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7
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Kusumoto FM, Schoenfeld MH, Barrett C, Edgerton JR, Ellenbogen KA, Gold MR, Goldschlager NF, Hamilton RM, Joglar JA, Kim RJ, Lee R, Marine JE, McLeod CJ, Oken KR, Patton KK, Pellegrini CN, Selzman KA, Thompson A, Varosy PD. 2018 ACC/AHA/HRS guideline on the evaluation and management of patients with bradycardia and cardiac conduction delay. Heart Rhythm 2019; 16:e128-e226. [DOI: 10.1016/j.hrthm.2018.10.037] [Citation(s) in RCA: 41] [Impact Index Per Article: 8.2] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 10/26/2018] [Indexed: 12/13/2022]
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8
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Kusumoto FM, Schoenfeld MH, Barrett C, Edgerton JR, Ellenbogen KA, Gold MR, Goldschlager NF, Hamilton RM, Joglar JA, Kim RJ, Lee R, Marine JE, McLeod CJ, Oken KR, Patton KK, Pellegrini CN, Selzman KA, Thompson A, Varosy PD. 2018 ACC/AHA/HRS Guideline on the Evaluation and Management of Patients With Bradycardia and Cardiac Conduction Delay: A Report of the American College of Cardiology/American Heart Association Task Force on Clinical Practice Guidelines and the Heart Rhythm Society. Circulation 2019; 140:e382-e482. [DOI: 10.1161/cir.0000000000000628] [Citation(s) in RCA: 97] [Impact Index Per Article: 19.4] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 12/20/2022]
Affiliation(s)
| | | | | | | | - Kenneth A. Ellenbogen
- Writing committee members are required to recuse themselves from voting on sections to which their specific relationships with industry may apply; see Appendix 1 for detailed information
- ACC/AHA Representative
| | - Michael R. Gold
- Writing committee members are required to recuse themselves from voting on sections to which their specific relationships with industry may apply; see Appendix 1 for detailed information
- HRS Representative
| | | | | | - José A. Joglar
- ACC/AHA Task Force on Clinical Practice Guidelines Liaison
| | | | | | | | | | | | | | - Cara N. Pellegrini
- Writing committee members are required to recuse themselves from voting on sections to which their specific relationships with industry may apply; see Appendix 1 for detailed information
- HRS Representative
- Dr. Pellegrini contributed to this article in her personal capacity. The views expressed are her own and do not necessarily represent the views of the US Department of Veterans Affairs or the US government
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9
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Kusumoto FM, Schoenfeld MH, Barrett C, Edgerton JR, Ellenbogen KA, Gold MR, Goldschlager NF, Hamilton RM, Joglar JA, Kim RJ, Lee R, Marine JE, McLeod CJ, Oken KR, Patton KK, Pellegrini CN, Selzman KA, Thompson A, Varosy PD. 2018 ACC/AHA/HRS Guideline on the Evaluation and Management of Patients With Bradycardia and Cardiac Conduction Delay. J Am Coll Cardiol 2019; 74:e51-e156. [DOI: 10.1016/j.jacc.2018.10.044] [Citation(s) in RCA: 151] [Impact Index Per Article: 30.2] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 12/12/2022]
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10
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Kusumoto FM, Schoenfeld MH, Barrett C, Edgerton JR, Ellenbogen KA, Gold MR, Goldschlager NF, Hamilton RM, Joglar JA, Kim RJ, Lee R, Marine JE, McLeod CJ, Oken KR, Patton KK, Pellegrini CN, Selzman KA, Thompson A, Varosy PD. 2018 ACC/AHA/HRS Guideline on the Evaluation and Management of Patients With Bradycardia and Cardiac Conduction Delay: Executive Summary. J Am Coll Cardiol 2019; 74:932-987. [DOI: 10.1016/j.jacc.2018.10.043] [Citation(s) in RCA: 144] [Impact Index Per Article: 28.8] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 12/25/2022]
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11
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Canine and human sinoatrial node: differences and similarities in the structure, function, molecular profiles, and arrhythmia. J Vet Cardiol 2018; 22:2-19. [PMID: 30559056 DOI: 10.1016/j.jvc.2018.10.004] [Citation(s) in RCA: 25] [Impact Index Per Article: 4.2] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/20/2018] [Revised: 10/02/2018] [Accepted: 10/02/2018] [Indexed: 12/17/2022]
Abstract
The sinoatrial node (SAN) is the primary pacemaker in canine and human hearts. The SAN in both species has a unique three-dimensional heterogeneous structure characterized by small pacemaker myocytes enmeshed within fibrotic strands, which partially insulate the cells from aberrant atrial activation. The SAN pacemaker tissue expresses a unique signature of proteins and receptors that mediate SAN automaticity, ion channel currents, and cell-to-cell communication, which are predominantly similar in both species. Recent intramural optical mapping, integrated with structural and molecular studies, has revealed the existence of up to five specialized SAN conduction pathways that preferentially conduct electrical activation to atrial tissues. The intrinsic heart rate, intranodal leading pacemaker shifts, and changes in conduction in response to physiological and pathophysiological stimuli are similar. Structural and/or functional impairments due to cardiac diseases including heart failure cause SAN dysfunctions (SNDs) in both species. These dysfunctions are usually manifested as severe bradycardia, tachy-brady arrhythmias, and conduction abnormalities including exit block and SAN reentry, which could lead to atrial tachycardia and fibrillation, cardiac arrest, and heart failure. Pharmaceutical drugs and implantable pacemakers are only partially successful in managing SNDs, emphasizing a critical need to develop targeted mechanism-based therapies to treat SNDs. Because several structural and functional characteristics are similar between the canine and human SAN, research in these species may be mutually beneficial for developing novel treatment approaches. This review describes structural, functional, and molecular similarities and differences between the canine and human SAN, with special emphasis on arrhythmias and unique causal mechanisms of SND in diseased hearts.
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12
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Kusumoto FM, Schoenfeld MH, Barrett C, Edgerton JR, Ellenbogen KA, Gold MR, Goldschlager NF, Hamilton RM, Joglar JA, Kim RJ, Lee R, Marine JE, McLeod CJ, Oken KR, Patton KK, Pellegrini CN, Selzman KA, Thompson A, Varosy PD. 2018 ACC/AHA/HRS guideline on the evaluation and management of patients with bradycardia and cardiac conduction delay: Executive summary: A Report of the American College of Cardiology/American Heart Association Task Force on Clinical Practice Guidelines, and the Heart Rhythm Society. Heart Rhythm 2018; 16:e227-e279. [PMID: 30412777 DOI: 10.1016/j.hrthm.2018.10.036] [Citation(s) in RCA: 7] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Key Words] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 10/26/2018] [Indexed: 12/22/2022]
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13
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Kusumoto FM, Schoenfeld MH, Barrett C, Edgerton JR, Ellenbogen KA, Gold MR, Goldschlager NF, Hamilton RM, Joglar JA, Kim RJ, Lee R, Marine JE, McLeod CJ, Oken KR, Patton KK, Pellegrini CN, Selzman KA, Thompson A, Varosy PD. 2018 ACC/AHA/HRS Guideline on the Evaluation and Management of Patients With Bradycardia and Cardiac Conduction Delay: Executive Summary: A Report of the American College of Cardiology/American Heart Association Task Force on Clinical Practice Guidelines, and the Heart Rhythm Society. Circulation 2018; 140:e333-e381. [PMID: 30586771 DOI: 10.1161/cir.0000000000000627] [Citation(s) in RCA: 29] [Impact Index Per Article: 4.8] [Reference Citation Analysis] [Key Words] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 02/07/2023]
Affiliation(s)
| | | | | | | | - Kenneth A Ellenbogen
- Writing committee members are required to recuse themselves from voting on sections to which their specific relationships with industry may apply; see Appendix 1 for detailed information.,ACC/AHA Representative
| | - Michael R Gold
- Writing committee members are required to recuse themselves from voting on sections to which their specific relationships with industry may apply; see Appendix 1 for detailed information.,HRS Representative
| | | | | | - José A Joglar
- ACC/AHA Task Force on Clinical Practice Guidelines Liaison
| | | | | | | | | | | | | | - Cara N Pellegrini
- Writing committee members are required to recuse themselves from voting on sections to which their specific relationships with industry may apply; see Appendix 1 for detailed information.,HRS Representative.,Dr. Pellegrini contributed to this article in her personal capacity. The views expressed are her own and do not necessarily represent the views of the US Department of Veterans Affairs or the US government
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14
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Ward J, DeFrancesco T, Tou S, Atkins C, Griffith E, Keene B. Outcome and survival in canine sick sinus syndrome and sinus node dysfunction: 93 cases (2002–2014). J Vet Cardiol 2016; 18:199-212. [DOI: 10.1016/j.jvc.2016.04.004] [Citation(s) in RCA: 20] [Impact Index Per Article: 2.5] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/27/2015] [Revised: 03/29/2016] [Accepted: 04/08/2016] [Indexed: 12/01/2022]
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Lou Q, Hansen BJ, Fedorenko O, Csepe TA, Kalyanasundaram A, Li N, Hage LT, Glukhov AV, Billman GE, Weiss R, Mohler PJ, Györke S, Biesiadecki BJ, Carnes CA, Fedorov VV. Upregulation of adenosine A1 receptors facilitates sinoatrial node dysfunction in chronic canine heart failure by exacerbating nodal conduction abnormalities revealed by novel dual-sided intramural optical mapping. Circulation 2014; 130:315-24. [PMID: 24838362 DOI: 10.1161/circulationaha.113.007086] [Citation(s) in RCA: 55] [Impact Index Per Article: 5.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 02/02/2023]
Abstract
BACKGROUND Although sinoatrial node (SAN) dysfunction is a hallmark of human heart failure (HF), the underlying mechanisms remain poorly understood. We aimed to examine the role of adenosine in SAN dysfunction and tachy-brady arrhythmias in chronic HF. METHODS AND RESULTS We applied multiple approaches to characterize SAN structure, SAN function, and adenosine A1 receptor expression in control (n=17) and 4-month tachypacing-induced chronic HF (n=18) dogs. Novel intramural optical mapping of coronary-perfused right atrial preparations revealed that adenosine (10 μmol/L) markedly prolonged postpacing SAN conduction time in HF by 206 ± 99 milliseconds (versus 66 ± 21 milliseconds in controls; P=0.02). Adenosine induced SAN intranodal conduction block or microreentry in 6 of 8 dogs with HF versus 0 of 7 controls (P=0.007). Adenosine-induced SAN conduction abnormalities and automaticity depression caused postpacing atrial pauses in HF versus control dogs (17.1 ± 28.9 versus 1.5 ± 1.3 seconds; P<0.001). Furthermore, 10 μmol/L adenosine shortened atrial repolarization and led to pacing-induced atrial fibrillation in 6 of 7 HF versus 0 of 7 control dogs (P=0.002). Adenosine-induced SAN dysfunction and atrial fibrillation were abolished or prevented by adenosine A1 receptor antagonists (50 μmol/L theophylline/1 μmol/L 8-cyclopentyl-1,3-dipropylxanthine). Adenosine A1 receptor protein expression was significantly upregulated during HF in the SAN (by 47 ± 19%) and surrounding atrial myocardium (by 90 ± 40%). Interstitial fibrosis was significantly increased within the SAN in HF versus control dogs (38 ± 4% versus 23 ± 4%; P<0.001). CONCLUSIONS In chronic HF, adenosine A1 receptor upregulation in SAN pacemaker and atrial cardiomyocytes may increase cardiac sensitivity to adenosine. This effect may exacerbate conduction abnormalities in the structurally impaired SAN, leading to SAN dysfunction, and potentiate atrial repolarization shortening, thereby facilitating atrial fibrillation. Atrial fibrillation may further depress SAN function and lead to tachy-brady arrhythmias in HF.
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Affiliation(s)
- Qing Lou
- From the Department of Physiology and Cell Biology (Q.L., B.J.H., O.F., T.A.C., A.K., N.L., L.T.H., A.V.G., G.E.B., P.J.M., S.G., B.J.B., V.V.F.), Davis Heart & Lung Research Institute (Q.L., A.K., G.E.B., R.W., P.J.M., S.G., B.J.B., C.A.C., V.V.F.), and Department of Internal Medicine (R.W., P.J.M.), The Ohio State University Wexner Medical Center, Columbus, OH; Mental Health Research Institute and National Research Tomsk Polytechnic University, Tomsk, Russia (O.F.); and College of Pharmacy, The Ohio State University, Columbus (C.A.C.)
| | - Brian J Hansen
- From the Department of Physiology and Cell Biology (Q.L., B.J.H., O.F., T.A.C., A.K., N.L., L.T.H., A.V.G., G.E.B., P.J.M., S.G., B.J.B., V.V.F.), Davis Heart & Lung Research Institute (Q.L., A.K., G.E.B., R.W., P.J.M., S.G., B.J.B., C.A.C., V.V.F.), and Department of Internal Medicine (R.W., P.J.M.), The Ohio State University Wexner Medical Center, Columbus, OH; Mental Health Research Institute and National Research Tomsk Polytechnic University, Tomsk, Russia (O.F.); and College of Pharmacy, The Ohio State University, Columbus (C.A.C.)
| | - Olga Fedorenko
- From the Department of Physiology and Cell Biology (Q.L., B.J.H., O.F., T.A.C., A.K., N.L., L.T.H., A.V.G., G.E.B., P.J.M., S.G., B.J.B., V.V.F.), Davis Heart & Lung Research Institute (Q.L., A.K., G.E.B., R.W., P.J.M., S.G., B.J.B., C.A.C., V.V.F.), and Department of Internal Medicine (R.W., P.J.M.), The Ohio State University Wexner Medical Center, Columbus, OH; Mental Health Research Institute and National Research Tomsk Polytechnic University, Tomsk, Russia (O.F.); and College of Pharmacy, The Ohio State University, Columbus (C.A.C.)
| | - Thomas A Csepe
- From the Department of Physiology and Cell Biology (Q.L., B.J.H., O.F., T.A.C., A.K., N.L., L.T.H., A.V.G., G.E.B., P.J.M., S.G., B.J.B., V.V.F.), Davis Heart & Lung Research Institute (Q.L., A.K., G.E.B., R.W., P.J.M., S.G., B.J.B., C.A.C., V.V.F.), and Department of Internal Medicine (R.W., P.J.M.), The Ohio State University Wexner Medical Center, Columbus, OH; Mental Health Research Institute and National Research Tomsk Polytechnic University, Tomsk, Russia (O.F.); and College of Pharmacy, The Ohio State University, Columbus (C.A.C.)
| | - Anuradha Kalyanasundaram
- From the Department of Physiology and Cell Biology (Q.L., B.J.H., O.F., T.A.C., A.K., N.L., L.T.H., A.V.G., G.E.B., P.J.M., S.G., B.J.B., V.V.F.), Davis Heart & Lung Research Institute (Q.L., A.K., G.E.B., R.W., P.J.M., S.G., B.J.B., C.A.C., V.V.F.), and Department of Internal Medicine (R.W., P.J.M.), The Ohio State University Wexner Medical Center, Columbus, OH; Mental Health Research Institute and National Research Tomsk Polytechnic University, Tomsk, Russia (O.F.); and College of Pharmacy, The Ohio State University, Columbus (C.A.C.)
| | - Ning Li
- From the Department of Physiology and Cell Biology (Q.L., B.J.H., O.F., T.A.C., A.K., N.L., L.T.H., A.V.G., G.E.B., P.J.M., S.G., B.J.B., V.V.F.), Davis Heart & Lung Research Institute (Q.L., A.K., G.E.B., R.W., P.J.M., S.G., B.J.B., C.A.C., V.V.F.), and Department of Internal Medicine (R.W., P.J.M.), The Ohio State University Wexner Medical Center, Columbus, OH; Mental Health Research Institute and National Research Tomsk Polytechnic University, Tomsk, Russia (O.F.); and College of Pharmacy, The Ohio State University, Columbus (C.A.C.)
| | - Lori T Hage
- From the Department of Physiology and Cell Biology (Q.L., B.J.H., O.F., T.A.C., A.K., N.L., L.T.H., A.V.G., G.E.B., P.J.M., S.G., B.J.B., V.V.F.), Davis Heart & Lung Research Institute (Q.L., A.K., G.E.B., R.W., P.J.M., S.G., B.J.B., C.A.C., V.V.F.), and Department of Internal Medicine (R.W., P.J.M.), The Ohio State University Wexner Medical Center, Columbus, OH; Mental Health Research Institute and National Research Tomsk Polytechnic University, Tomsk, Russia (O.F.); and College of Pharmacy, The Ohio State University, Columbus (C.A.C.)
| | - Alexey V Glukhov
- From the Department of Physiology and Cell Biology (Q.L., B.J.H., O.F., T.A.C., A.K., N.L., L.T.H., A.V.G., G.E.B., P.J.M., S.G., B.J.B., V.V.F.), Davis Heart & Lung Research Institute (Q.L., A.K., G.E.B., R.W., P.J.M., S.G., B.J.B., C.A.C., V.V.F.), and Department of Internal Medicine (R.W., P.J.M.), The Ohio State University Wexner Medical Center, Columbus, OH; Mental Health Research Institute and National Research Tomsk Polytechnic University, Tomsk, Russia (O.F.); and College of Pharmacy, The Ohio State University, Columbus (C.A.C.)
| | - George E Billman
- From the Department of Physiology and Cell Biology (Q.L., B.J.H., O.F., T.A.C., A.K., N.L., L.T.H., A.V.G., G.E.B., P.J.M., S.G., B.J.B., V.V.F.), Davis Heart & Lung Research Institute (Q.L., A.K., G.E.B., R.W., P.J.M., S.G., B.J.B., C.A.C., V.V.F.), and Department of Internal Medicine (R.W., P.J.M.), The Ohio State University Wexner Medical Center, Columbus, OH; Mental Health Research Institute and National Research Tomsk Polytechnic University, Tomsk, Russia (O.F.); and College of Pharmacy, The Ohio State University, Columbus (C.A.C.)
| | - Raul Weiss
- From the Department of Physiology and Cell Biology (Q.L., B.J.H., O.F., T.A.C., A.K., N.L., L.T.H., A.V.G., G.E.B., P.J.M., S.G., B.J.B., V.V.F.), Davis Heart & Lung Research Institute (Q.L., A.K., G.E.B., R.W., P.J.M., S.G., B.J.B., C.A.C., V.V.F.), and Department of Internal Medicine (R.W., P.J.M.), The Ohio State University Wexner Medical Center, Columbus, OH; Mental Health Research Institute and National Research Tomsk Polytechnic University, Tomsk, Russia (O.F.); and College of Pharmacy, The Ohio State University, Columbus (C.A.C.)
| | - Peter J Mohler
- From the Department of Physiology and Cell Biology (Q.L., B.J.H., O.F., T.A.C., A.K., N.L., L.T.H., A.V.G., G.E.B., P.J.M., S.G., B.J.B., V.V.F.), Davis Heart & Lung Research Institute (Q.L., A.K., G.E.B., R.W., P.J.M., S.G., B.J.B., C.A.C., V.V.F.), and Department of Internal Medicine (R.W., P.J.M.), The Ohio State University Wexner Medical Center, Columbus, OH; Mental Health Research Institute and National Research Tomsk Polytechnic University, Tomsk, Russia (O.F.); and College of Pharmacy, The Ohio State University, Columbus (C.A.C.)
| | - Sándor Györke
- From the Department of Physiology and Cell Biology (Q.L., B.J.H., O.F., T.A.C., A.K., N.L., L.T.H., A.V.G., G.E.B., P.J.M., S.G., B.J.B., V.V.F.), Davis Heart & Lung Research Institute (Q.L., A.K., G.E.B., R.W., P.J.M., S.G., B.J.B., C.A.C., V.V.F.), and Department of Internal Medicine (R.W., P.J.M.), The Ohio State University Wexner Medical Center, Columbus, OH; Mental Health Research Institute and National Research Tomsk Polytechnic University, Tomsk, Russia (O.F.); and College of Pharmacy, The Ohio State University, Columbus (C.A.C.)
| | - Brandon J Biesiadecki
- From the Department of Physiology and Cell Biology (Q.L., B.J.H., O.F., T.A.C., A.K., N.L., L.T.H., A.V.G., G.E.B., P.J.M., S.G., B.J.B., V.V.F.), Davis Heart & Lung Research Institute (Q.L., A.K., G.E.B., R.W., P.J.M., S.G., B.J.B., C.A.C., V.V.F.), and Department of Internal Medicine (R.W., P.J.M.), The Ohio State University Wexner Medical Center, Columbus, OH; Mental Health Research Institute and National Research Tomsk Polytechnic University, Tomsk, Russia (O.F.); and College of Pharmacy, The Ohio State University, Columbus (C.A.C.)
| | - Cynthia A Carnes
- From the Department of Physiology and Cell Biology (Q.L., B.J.H., O.F., T.A.C., A.K., N.L., L.T.H., A.V.G., G.E.B., P.J.M., S.G., B.J.B., V.V.F.), Davis Heart & Lung Research Institute (Q.L., A.K., G.E.B., R.W., P.J.M., S.G., B.J.B., C.A.C., V.V.F.), and Department of Internal Medicine (R.W., P.J.M.), The Ohio State University Wexner Medical Center, Columbus, OH; Mental Health Research Institute and National Research Tomsk Polytechnic University, Tomsk, Russia (O.F.); and College of Pharmacy, The Ohio State University, Columbus (C.A.C.)
| | - Vadim V Fedorov
- From the Department of Physiology and Cell Biology (Q.L., B.J.H., O.F., T.A.C., A.K., N.L., L.T.H., A.V.G., G.E.B., P.J.M., S.G., B.J.B., V.V.F.), Davis Heart & Lung Research Institute (Q.L., A.K., G.E.B., R.W., P.J.M., S.G., B.J.B., C.A.C., V.V.F.), and Department of Internal Medicine (R.W., P.J.M.), The Ohio State University Wexner Medical Center, Columbus, OH; Mental Health Research Institute and National Research Tomsk Polytechnic University, Tomsk, Russia (O.F.); and College of Pharmacy, The Ohio State University, Columbus (C.A.C.).
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16
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Lou Q, Glukhov AV, Hansen B, Hage L, Vargas-Pinto P, Billman GE, Carnes CA, Fedorov VV. Tachy-brady arrhythmias: the critical role of adenosine-induced sinoatrial conduction block in post-tachycardia pauses. Heart Rhythm 2012; 10:110-8. [PMID: 22985657 DOI: 10.1016/j.hrthm.2012.09.012] [Citation(s) in RCA: 23] [Impact Index Per Article: 1.9] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 06/07/2012] [Indexed: 11/30/2022]
Abstract
BACKGROUND In patients with sinoatrial nodal (SAN) dysfunction, atrial pauses lasting several seconds may follow rapid atrial pacing or paroxysmal tachycardia (tachy-brady arrhythmias). Clinical studies suggest that adenosine may play an important role in SAN dysfunction, but the mechanism remains unclear. OBJECTIVE To define the mechanism of SAN dysfunction induced by the combination of adenosine and tachycardia. METHODS We studied the mechanism of SAN dysfunction produced by a combination of adenosine and rapid atrial pacing in isolated coronary-perfused canine atrial preparations by using high-resolution optical mapping (n = 9). Sinus cycle length and sinoatrial conduction time (SACT) were measured during adenosine (1-100 μM) and DPCPX (1 μM; A1 receptor antagonist; n = 7) perfusion. Sinoatrial node recovery time was measured after 1 minute of "slow" pacing (3.3 Hz) or tachypacing (7-9 Hz). RESULTS Adenosine significantly increased sinus cycle length (477 ± 62 ms vs 778 ± 114 ms; P<.01) and SACT during sinus rhythm (41 ± 11 ms vs 86 ± 16 ms; P<.01) in a dose-dependent manner. Adenosine dramatically affected SACT of the first SAN beat after tachypacing (41 ± 5 ms vs 221 ± 98 ms; P<.01). Moreover, at high concentrations of adenosine (10-100 μM), termination of tachypacing or atrial flutter/fibrillation produced atrial pauses of 4.2 ± 3.4 seconds (n = 5) owing to conduction block between the SAN and the atria, despite a stable SAN intrinsic rate. Conduction block was preferentially related to depressed excitability in SAN conduction pathways. Adenosine-induced changes were reversible on washout or DPCPX treatment. CONCLUSIONS These data directly demonstrate that adenosine contributes to post-tachycardia atrial pauses through SAN exit block rather than slowed pacemaker automaticity. Thus, these data suggest an important modulatory role of adenosine in tachy-brady syndrome.
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Affiliation(s)
- Qing Lou
- Department of Physiology and Cell Biology, The Ohio State University, Columbus, Ohio 43210-1218, USA
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17
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Rucinski P, Rubaj A, Kutarski A. Pharmacotherapy changes following pacemaker implantation in patients with bradycardia-tachycardia syndrome. Expert Opin Pharmacother 2007; 7:2203-13. [PMID: 17059377 DOI: 10.1517/14656566.7.16.2203] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/05/2022]
Abstract
The management of bradycardia-tachycardia syndrome (BTS) includes bradycardia and tachyarrhythmia therapy. At present, the treatment for symptomatic bradycardia in BTS patients is permanent cardiac pacing. The pharmacological treatment of atrial tachyarrhythmias comprises of rhythm and rate control, and prevention of thromboembolism. Patients with BTS often require both pacemaker and drug therapy. This article reviews the interactions of pacing and drug therapies in BTS. Drugs that alter cardiac electrophysiological properties may influence pacemaker indications, pacing mode selection, efficacy of pacing algorithms and pacing performance. Pacing by preventing drug-induced bradycardia increases the safety of pharmacotherapy and, thus, allows the intensification of those treatments. Pacing therapy and antiarrhythmic drugs used together as a hybrid therapy have a synergistic effect in the prevention of atrial tachyarrhythmias. Atrial-based pacing may reduce atrial tachyarrhythmia burden, allowing reduction of rhythm and rate control. Contemporary pacemakers' memory functions may help guide rhythm and rate control, as well as anticoagulation pharmacotherapy.
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Affiliation(s)
- Piotr Rucinski
- Department of Cardiology, Medical University of Lublin, 8 Jaczewskiego Street, 20-954 Lublin, Poland.
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18
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Moriya I, Takahashi T, Nomura Y, Kawaura K, Kusaka K, Yamakawa J, Fujioka N, Okubo S, Itoh T, Kanda T. Chronotropic Effect of the Antithrombotic Agent Cilostazol in a Patient with Sick Sinus Syndrome and Syncope. J Int Med Res 2004; 32:549-51. [PMID: 15458288 DOI: 10.1177/147323000403200513] [Citation(s) in RCA: 9] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/15/2022] Open
Abstract
In this case report we describe an 80-year-old man with sick sinus syndrome (SSS) who developed syncope attacks. The diagnosis of SSS was based on electrocardiographic evidence of markedly prolonged sinus arrests associated with syncope attacks while in hospital. The patient was given cilostazol, an anti-thrombotic agent that selectively inhibits cyclic nucleotide phosphodiesterase type 3, at a dose of 100 mg twice daily. The syncope attacks ceased, and an electrocardiogram obtained 1 week after the start of cilostazol administration showed no evidence of sinus arrest. The outcome of this case suggests that cilostazol may be useful in patients with syncope attacks due to SSS, although the long-term chronotropic effects of cilostazol need to be evaluated.
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Affiliation(s)
- I Moriya
- Department of General Medicine, Kanazawa Medical University, Uchinada-machi, Kahoku-gun, Ishikawa, Japan
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19
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Park HW, Cho JG, Yum JH, Hong YJ, Lim JH, Kim HG, Kim JH, Ahn YK, Jeong MH, Park JC, Kang JC. Clinical characteristics of hypervagotonic sinus node dysfunction. Korean J Intern Med 2004; 19:155-9. [PMID: 15481606 PMCID: PMC4531564 DOI: 10.3904/kjim.2004.19.3.155] [Citation(s) in RCA: 8] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 11/27/2022] Open
Abstract
BACKGROUND Sinus node dysfunction (SND) is caused not only by intrinsic sinus node disease, but also by the extrinsic factors. Among the extrinsic factors, autonomic imbalance is most common. Symptomatic SND usually requires permanent pacemaker therapy. However, the clinical characteristics and patient response to medical therapy for hypervagotonic SND have not been properly clarified. MATERIALS AND METHODS Thirty two patients (14 men, 18 women, 51 +/- 14 years) with hypervagotonic SND were included in this study, but those patients who had taken calcium antagonists, beta-blockers or other antiarrhythmic drugs were excluded. Hypervagotonic SND was diagnosed if the abnormal electrophysiologic properties of the sinus node were normalized after the administration of atropine (0.04 mg/kg). RESULTS The presenting arrhythmias were 16 cases of sinus bradycardia (50.0%), 12 of sinus pause (37.5%), 3 of sinoatrial block (9.4%) and 1 of tachy-bradycardia (3.1%). Nine (28.1%) patients had hypertension, 7 (21.9%) smoked, 2 (6.3%) had diabetes mellitus, and 1 (3.1%) had hypercholesterolemia. Among the patients, 3 had no remarkable symptoms, 13 had dizziness, 7 had syncope, 3 had weakness and 6 had shortness of breath. Twenty five (78.1%) patients were treated with theophylline, 1 patient with tachy-bradycardia syndrome was treated with digoxin and propafenone, and 6 (18.8%) were treated with no medication. During the 43 +/- 28 month follow-up, 25 patients remained asymptomatic, but 6 who took no medication developed mild dizziness. One patient needed permanent pacemaker implantation owing to recurrent syncope despite of theophylline treatment. CONCLUSION These results show that hypervagotonic SND has a benign course and most of the patients can be managed safely without implanting a pacemaker. (Ed note: I like the abstract. It is short and direct, as it should be.)
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Affiliation(s)
| | - Jeong-Gwan Cho
- Correspondence to: Jeong-Gwan Cho, M.D., FACC, Division of Cardiology, Chonnam University Hospital, Hakdong 8, Gwangju 501-757, Korea, Tel: 82-62-220-6242, Fax: 82-62-226-0179, E-mail:
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20
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Moneva-Jordan A, Corcoran BM, French A, Dukes-McEwan J, Martin MW, Luis Fuentes V, Hitchcock LS, Bonagura JD. Sick sinus syndrome in nine West Highland white terriers. Vet Rec 2001; 148:142-7. [PMID: 11271916 DOI: 10.1136/vr.148.5.142] [Citation(s) in RCA: 23] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/04/2022]
Abstract
Sick sinus syndrome is a clinical term used to describe the clinical signs of sinus node dysfunction. This paper describes the clinical data from nine West Highland white terriers, eight females and one male, in which a diagnosis of sick sinus syndrome was made. The most common clinical signs were episodic weakness and presyncope. Electrocardiographic findings included sinus bradycardia, sinus arrest with or without escape complexes, disturbances of atrioventricular conduction, paroxysmal supraventricular tachycardia, or some combination of these dysrhythmias. The main radiographic changes were mild right-sided cardiomegaly in five cases, and a slight increase in bronchial and interstitial markings in four, but there was no evidence of congestive heart failure in any of the dogs. Echocardiography revealed mild to moderate mitral endocardiosis in three cases with no other significant abnormalities. The dogs' responses to parenteral atropine were variable and were not necessarily related to their response to oral anticholinergic agents. Five of the dogs were initially treated with propantheline bromide, but in only two of them were the clinical signs controlled in the long term. Six of the dogs were successfully treated by the implantation of a transvenous pacemaker.
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Affiliation(s)
- A Moneva-Jordan
- Hospital for Small Animals, Department of Veterinary Clinical Studies, Royal (Dick) School of Veterinary Studies, The University of Edinburgh, Easter Bush Veterinary Centre, Roslin, Midlothian
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21
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Dixon WC, Bauch TD. Effects of theophylline on exercise indices in a patient with chronotropic incompetence. Clin Cardiol 2000; 23:787-9. [PMID: 11061060 PMCID: PMC6654921 DOI: 10.1002/clc.4960231019] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 03/12/1999] [Accepted: 09/16/1999] [Indexed: 11/06/2022] Open
Abstract
Several investigators have documented the successful use of oral sustained-release theophylline in treating symptomatic bradycardia and sick sinus syndrome. This paper reports a case of chronotropic incompetence in which specific exercise indices, including the chronotropic response index, were used to measure the therapeutic efficacy of theophylline.
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Affiliation(s)
- W C Dixon
- Department of Medicine, Brooke Army Medical Center, San Antonio, Texas 78234, USA
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22
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Mitrani RD, Simmons JD, Interian A, Castellanos A, Myerburg RJ. Cardiac pacemakers: current and future status. Curr Probl Cardiol 1999; 24:341-420. [PMID: 10388947 DOI: 10.1016/s0146-2806(99)90002-6] [Citation(s) in RCA: 8] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/16/2022]
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23
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Pasic M, Musci M, Siniawski H, Edelmann B, Tedoriya T, Hetzer R. Transient sinus node dysfunction after the Cox-maze III procedure in patients with organic heart disease and chronic fixed atrial fibrillation. J Am Coll Cardiol 1998; 32:1040-7. [PMID: 9768730 DOI: 10.1016/s0735-1097(98)00358-1] [Citation(s) in RCA: 45] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 11/18/2022]
Abstract
OBJECTIVES This prospective study examined types, frequency and time dependency of the electrophysiologic manifestation of the sinus node dysfunction after the Cox-maze III procedure--the technique of choice for the management of medically refractory atrial fibrillation-in patients with organic heart disease, chronic fixed atrial fibrillation and no preoperatively overt dysfunction of the sinus node. BACKGROUND The original maze procedure was modified twice in order to reduce the high incidence of the sinus node inability to generate an appropriate sinus tachycardia in response to maximal exercise, and occasional left atrial dysfunction. Despite these modifications, postoperative disturbance of sinus node function can be frequently observed. METHODS In 15 adult patients, standard electrocardiogram, 24-h Holter monitoring, power spectral analysis of heart variability, exercise testing, Valsalva maneuver and rapid positional changes were performed 3, 6 and 12 months after the Cox-maze III procedure and mitral valve surgery or closure of atrial septal defect. RESULTS Electrocardiographic manifestations of sinus node dysfunction were identified in 12 patients at 3 months, in 6 patients at 6 months, and in 0 patients at 12 months after surgery. The heart rate response to exercise during the first 6 months was reduced in the maze group and became fully normal at 12 months. Power spectral analysis of heart rate variability showed very low power values at 1 month with inhibited cardiac autonomic activity and no response on sympathetic stress. A potential of recovery of cardiac autonomic activity was documented 12 months after surgery. CONCLUSIONS The manifestations of sinus node dysfunction following the Cox-maze III procedure were time dependent and their frequency and intensity progressively decreased and disappeared within 12 months after surgery.
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Affiliation(s)
- M Pasic
- Deutsches Herzzentrum Berlin, Klinik für Herz-, Thorax- und Gefässchirurgie, Berlin, Germany.
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24
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Ling CA, Crouch MA. Theophylline for chronic symptomatic bradycardia in the elderly. Ann Pharmacother 1998; 32:837-9. [PMID: 9681101 DOI: 10.1345/aph.17463] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/08/2023] Open
Abstract
The treatment of choice for chronic, symptomatic bradycardia is the placement of a cardiac pacemaker. Individuals who refuse or cannot tolerate pacemaker insertion usually require pharmacologic therapy. Hydralazine, prazosin, anticholinergics, and sympathomimetic agents have been administered for this indication, but adverse effects and limited data hinder routine, long-term use. Theophylline has emerged as a reasonable alternative strategy. For the medical management of bradycardia in the elderly, the literature supports theophylline dosages between 400 and 600 mg/d (approximately 8 mg/kg/d) administered in divided doses. This dosage range should result in a steady-state serum concentration between 5 and 15 mg/L. While some investigators recommend potentially higher initial doses (up to 12 mg/kg/d), lower dosages are more appropriate in the elderly due to decreased theophylline clearance. Initial dosage titration may be indicated and prolonged therapy is expected on the basis of the common etiologies of bradycardia in this patient group. Patient specifics such as altered theophylline metabolism (e.g., smoking), drug interactions (e.g., ciprofloxacin), and concomitant disease states (e.g., hepatic disease, heart failure) should always be considered in theophylline dosage recommendations. Clinicians should adjust the theophylline dose on the basis of patient response, including heart rate and clinical symptomatology, as well as measurement of occasional theophylline concentrations, if deemed appropriate. Theophylline should be avoided in the bradycardia-tachycardia manifestations of sick sinus syndrome or when ventricular ectopy is frequent. Additional investigation will further define the role of theophylline in elderly patients with chronic, symptomatic bradycardia.
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Affiliation(s)
- C A Ling
- Department of Pharmacy, Virginia Commonwealth University, Richmond 23298, USA
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Atarashi H, Endoh Y, Saitoh H, Kishida H, Hayakawa H. Chronotropic effects of cilostazol, a new antithrombotic agent, in patients with bradyarrhythmias. J Cardiovasc Pharmacol 1998; 31:534-9. [PMID: 9554801 DOI: 10.1097/00005344-199804000-00010] [Citation(s) in RCA: 51] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 02/07/2023]
Abstract
Whether phosphodiesterase inhibitors increase the heart rate in patients with bradyarrhythmias is not known. We attempted to determine whether the oral phosphodiesterase inhibitor cilostazol exhibits beneficial chronotropic effects in patients with symptomatic bradyarrhythmias. Twenty patients comprising eight with bradycardic atrial fibrillation, eight with sick sinus syndrome, and four with Wenckebach-type atrioventricular block, whose 24-h total heart-beat count was < or =70,000 beats and whose maximal RR interval was > or =2.5 s, were enrolled. Holter recordings (24-h) were made before and 2 weeks after oral daily administration of 200 mg of cilostazol. Cilostazol increased the 24-h total heart-beat count from 77,429 +/- 11,168 to 107,981 +/- 13,536 (95% confidence interval, 24,605-36,497; p < 0.0001), the minimal heart rate from 33 +/- 9 47 +/- 13 beats/min (95% confidence interval, 9-19 beats/min; p < 0.0001), and the maximal RR interval from 3,149 +/- 1,018 to 2,087 +/- 601 ms (95% confidence interval, -1,517 to -608 ms; p = 0.0001). Only two patients had headaches as adverse effects. In conclusion, cilostazol had a beneficial positive chronotropic effect in patients with bradyarrhythmias, especially with bradycardic atrial fibrillation and sick sinus syndrome.
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Affiliation(s)
- H Atarashi
- First Department of Internal Medicine, Nippon Medical School, Tokyo, Japan
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Lahaye S, Sheahan R, Darling D, Dorian P, Newman D. Serial measures of sinoatrial and atrioventricular nodal function in ambulatory patients. Pacing Clin Electrophysiol 1997; 20:2219-26. [PMID: 9309747 DOI: 10.1111/j.1540-8159.1997.tb04240.x] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 02/05/2023]
Abstract
We hypothesized that the outpatient assessment of SA and AV nodal (SAN, AVN) function could be a useful tool to determine the effectiveness of drugs and other treatments. We sought to examine the reproducibility, safety and ease of acquiring serial measurements of these parameters. Ten patients with permanent pacemakers underwent low current chest wall stimulation while their device was programmed to unipolar atrial triggered mode. Measurements at multiple conditioning drive train frequencies were obtained for: sinus nodal recovery time (SNRT); corrected sinus nodal recovery time (CSNRT); SA conduction time (SACT); AVN block cycle length (AVNBCL); and AVN effective refractory period (AVNERP). AVN function curves were also constructed. All studies were repeated after 2 weeks. Measures of sinus nodal and AVN function did not show significant differences between the two studies. The following co-efficients of correlation were obtained: SNRT800, r = 0.79; CSNRT800, r = 0.71; SNRT600, r = 0.71; CSNRT600, r = 0.44; SACT, r = 0.75; AVNBCL, r = 0.98; AVNERP800, r = 0.55; and AVNERP600, r = 0.99. AVN function curves did not significantly differ between week 1 versus week 2 at conditioning drive trains of either 800 ms or 600 ms. These data suggest that serial noninvasive electrophysiological measures of AVN and SAN function are reproducible over 2 weeks. Using data in this study, estimates of the sample size necessary for the evaluation of the effects of investigational drugs on the SAN and AVN in future studies are possible.
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Affiliation(s)
- S Lahaye
- Division of Cardiology, ST. Michael's Hospital, Toronto, Ontario, Canada
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Alboni P, Menozzi C, Brignole M, Paparella N, Gaggioli G, Lolli G, Cappato R. Effects of permanent pacemaker and oral theophylline in sick sinus syndrome the THEOPACE study: a randomized controlled trial. Circulation 1997; 96:260-6. [PMID: 9236443 DOI: 10.1161/01.cir.96.1.260] [Citation(s) in RCA: 93] [Impact Index Per Article: 3.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 02/04/2023]
Abstract
BACKGROUND Pacemakers and theophylline are currently being used to relieve symptoms in patients with sick sinus syndrome (SSS). However, the impact of either therapy on the natural course of the disease is unknown. We conducted a randomized controlled trial to prospectively assess the effects of pacemakers and theophylline in patients with SSS. METHODS AND RESULTS One hundred seven patients with symptomatic SSS (age, 73 +/- 11 years) were randomized to no treatment (control group, n = 35), oral theophylline (n = 36), or dual-chamber rate-responsive pacemaker therapy (n = 36). They were followed for up to 48 months (mean, 19 +/- 14 months). During follow-up, the occurrence of syncope was lower in the pacemaker group than in the control group (P = .02) and tended to be lower than in the theophylline group (P = .07). Heart failure occurred less often in patients assigned to pacemaker therapy and theophylline than in control patients (both, P = .05), whereas the incidence of sustained paroxysmal tachyarrhythmias, permanent atrial fibrillation, and thromboembolic events did not show any apparent difference among the three groups. Heart rate was higher in the theophylline group than in the control group. Both pacemaker therapy and theophylline improved symptom scores after 3 months of treatment; however, a similar improvement was observed in the control group. CONCLUSIONS In patients with symptomatic SSS, therapy with theophylline or dual-chamber pacemaker is associated with a lower incidence of heart failure; pacemaker therapy is also associated with a lower incidence of syncope. The therapeutic benefits of pacemakers and theophylline on symptoms are partly a result of spontaneous improvement of the disease.
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Affiliation(s)
- P Alboni
- Division of Cardiology, Ospedale Civile, Cento, Italy
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Bertolet BD, Belardinelli L, Franco EA, Nichols WW, Kerensky RA, Hill JA. Selective attenuation by N-0861 (N6-endonorboran-2-yl-9-methyladenine) of cardiac A1 adenosine receptor-mediated effects in humans. Circulation 1996; 93:1871-6. [PMID: 8635266 DOI: 10.1161/01.cir.93.10.1871] [Citation(s) in RCA: 23] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 02/01/2023]
Abstract
BACKGROUND To determine the adenosine receptor subtype selectivity of the novel antagonist N-0861, the A1 and A2 receptor-mediated cardiac effects of adenosine were investigated in 13 patients during continuous intravenous infusion and boluses of adenosine before and after intravenous infusion of N-0861. METHODS AND RESULTS Measurements of the the atria-to-His (A-H) interval, chest pain severity, and coronary blood flow velocity were made before and after low-dose (69 microg x kg(-1) x min(-1)) intravenous infusion and bolus (2.5 mg) adenosine. Two doses of N-0861 were infused intravenously, and the adenosine protocol was repeated. N-0861 0.25 mg/kg abolished the negative dromotropic effect (A-H interval prolongation) and chest discomfort experienced during infusion of adenosine and attenuated discomfort observed during the boluses of adenosine; however, the increase in coronary blood flow velocity was not significantly affected. CONCLUSIONS These actions of N-0861 support the concept that the negative dromotropic effect and anginalike pain caused by adenosine are A1 adenosine receptor-mediated, whereas the increase in coronary blood flow velocity is due to activation of A2 adenosine receptors. N-0861 appears to be an effective and selective A1 adenosine receptor antagonist in humans.
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Affiliation(s)
- B D Bertolet
- Department of Medicine, University of Florida Health Sciences Center, Gainesville, 32610-0277, USA
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Babuty D, Aupart M, Cosnay P, Sirinelli A, Rouchet S, Marchand M, Fauchier JP. Electrocardiographic and electrophysiologic properties of cardiac allografts. J Cardiovasc Electrophysiol 1994; 5:1053-63. [PMID: 7697207 DOI: 10.1111/j.1540-8167.1994.tb01147.x] [Citation(s) in RCA: 14] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 01/26/2023]
Abstract
The increasing number of heart transplant patients requires that physicians be able to recognize the electrocardiographic (ECG) and electrophysiologic properties of cardiac allografts. Cardiac allografts are characterized by modifications of resting ECGs and frequent arrhythmias in the postoperative period, and the loss of autonomic nervous control illustrated by permanent tachycardia and loss of heart rate variability during 24-hour ambulatory ECG recording. Some clinical and experimental observations suggest a mid-term reinnervation of the cardiac allograft, but this requires histologic confirmation. The electrophysiologic characteristics of the denervated myocardium are similar to those of the innervated myocardium at rest. However, supersensitivity to circulating catecholamines has been observed in cardiac allografts as in experimentally denervated hearts, which is responsible for a progressive increase in heart rate during exercise and a slow decrease during recovery. Supersensitivity of the denervated heart to acetylcholine may explain the high prevalence of donor sinus dysfunction due to impairment of its automaticity. More often, the sinus node dysfunction is transient and can be treated with an adenosine antagonist, such as theophylline, before permanent implantation of a pacemaker. In the case of pacemaker implantation, synchronization of the donor atria with the recipient atria is desirable, and an endocardial lead implantation is preferred. Several electrophysiologic changes have been observed during acute cardiac allograft rejection. From experimental studies, the most important of these are the disturbance of conduction in the atria and the atrioventricular node and a decrease in the amplitude of the ventricular potential. Initial studies on isolated myocytes show profound changes in membrane conductance during experimental cardiac rejection. The development of new noninvasive detection methods of cardiac allograft rejection, such as intramyocardial voltage electrogram monitoring and high-resolution ECG, could help early diagnosis.
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Affiliation(s)
- D Babuty
- Service de Cardiologie et d'Electrophysiologie, Hospital Trousseau, Tours, France
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Alboni P, Paparella N, Cappato R, Pirani R, Yiannacopulu P, Antonioli GE. Long-term effects of theophylline in atrial fibrillation with a slow ventricular response. Am J Cardiol 1993; 72:1142-5. [PMID: 8237803 DOI: 10.1016/0002-9149(93)90983-j] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 01/29/2023]
Abstract
In 17 patients (aged 78 +/- 9 years) with symptomatic atrial fibrillation and a slow ventricular response not related to drugs, a resting electrocardiogram and 24-hour Holter recording were obtained before and 5 to 6 days after administration of slow-release theophylline (700 mg/day), and successively every 3 months during the long-term phase. Fourteen patients had organic heart disease, and 13 complained of syncope or presyncope, and 4 of asthenia and easy fatigability. At the steady-state evaluation, theophylline significantly increased resting heart rate (HR) by 42%, mean 24-hour HR by 31% and minimal 24-hour HR by 34%. Cardiac pauses > 2,500 ms disappeared or markedly decreased. The daily number of wide QRS complexes increased. Serum theophylline level was 13 +/- 5 ng/ml. During the follow-up period (20 +/- 18 months), the mean daily theophylline dosage was 450 mg and the mean serum theophylline level 9 ng/ml. Seven patients died: 1 because of heart failure, and 6 because of noncardiac death. One patient complained of a syncopal episode during 1 visit. The drug markedly reduced asthenia and easy fatigability. During the long-term phase, HR increased spontaneously in 3 patients, and the treatment was interrupted. In 2 patients, theophylline had to be discontinued because of gastric intolerance. During long-term therapy, HR was similar to that observed at the steady-state evaluation, despite the reduction in daily dosage. The data suggest that theophylline is an effective therapy in most patients with symptomatic atrial fibrillation and a slow ventricular response.
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Affiliation(s)
- P Alboni
- Division of Cardiology, Ospedale Civile, Cento Fe, Italy
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