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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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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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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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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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Muresan L, Cismaru G, Martins RP, Bataglia A, Rosu R, Puiu M, Gusetu G, Mada RO, Muresan C, Ispas DR, Le Bouar R, Diene LL, Rugina E, Levy J, Klein C, Sellal JM, Poull IM, Laurent G, de Chillou C. Recommendations for the use of electrophysiological study: Update 2018. Hellenic J Cardiol 2018; 60:82-100. [PMID: 30278230 DOI: 10.1016/j.hjc.2018.09.002] [Citation(s) in RCA: 14] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/05/2018] [Revised: 08/31/2018] [Accepted: 09/24/2018] [Indexed: 12/16/2022] Open
Abstract
The field of cardiac electrophysiology has greatly developed during the past decades. Consequently, the use of electrophysiological studies (EPSs) in clinical practice has also significantly augmented, with a progressively increasing number of certified electrophysiology centers and specialists. Since Zipes et al published the Guidelines for Clinical Intracardiac Electrophysiology and Catheter Ablation Procedures in 1995, no official document summarizing current EPS indications has been published. The current paper focuses on summarizing all relevant data of the role of EPS in patients with different types of cardiac pathologies and provides up-to-date recommendations on this topic. For this purpose, the PubMed database was screened for relevant articles in English up to December 2018 and ESC and ACC/AHA Clinical Practice Guidelines, and EHRA/HRS/APHRS position statements related to the current topic were analyzed. Current recommendations for the use of EPS in clinical practice are discussed and presented in 17 distinct cardiac pathologies. A short rationale, evidence, and indications are provided for each cardiac disease/group of diseases. In conclusion, because of its capability to establish a diagnosis in patients with a variety of cardiac pathologies, the EPS remains a useful tool in the evaluation of patients with cardiac arrhythmias and conduction disorders and is capable of establishing indications for cardiac device implantation and guide catheter ablation procedures.
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Affiliation(s)
- Lucian Muresan
- "Emile Muller" Hospital, Cardiology Department, 68100 Mulhouse, France.
| | - Gabriel Cismaru
- Rehabilitation Hospital, Cardiology Department, 400347 Cluj-Napoca, Romania
| | - Raphaël Pedro Martins
- Centre Hospitalier Universitaire de Rennes, Cardiology Department, 35000 Rennes, France
| | - Alberto Bataglia
- Institut Lorrain du Coeur et des Vaisseaux « Louis Mathieu », Cardiology Department, Electrophysiology Department, 54000 Vandoeuvre-les-Nancy, France
| | - Radu Rosu
- Rehabilitation Hospital, Cardiology Department, 400347 Cluj-Napoca, Romania
| | - Mihai Puiu
- Rehabilitation Hospital, Cardiology Department, 400347 Cluj-Napoca, Romania
| | - Gabriel Gusetu
- Rehabilitation Hospital, Cardiology Department, 400347 Cluj-Napoca, Romania
| | - Razvan Olimpiu Mada
- "Niculae Stancioiu" Heart Institute, Cardiology Department, 400005 Cluj-Napoca, Romania
| | - Crina Muresan
- "Emile Muller" Hospital, Cardiology Department, 68100 Mulhouse, France
| | - Daniel Radu Ispas
- Rehabilitation Hospital, Cardiology Department, 400347 Cluj-Napoca, Romania
| | - Ronan Le Bouar
- "Emile Muller" Hospital, Cardiology Department, 68100 Mulhouse, France
| | | | - Elena Rugina
- "Emile Muller" Hospital, Cardiology Department, 68100 Mulhouse, France
| | - Jacques Levy
- "Emile Muller" Hospital, Cardiology Department, 68100 Mulhouse, France
| | - Cedric Klein
- Centre Hospitalier Universitaire de Lille, Cardiology Department, 59000 Lille, France
| | - Jean Marc Sellal
- Institut Lorrain du Coeur et des Vaisseaux « Louis Mathieu », Cardiology Department, Electrophysiology Department, 54000 Vandoeuvre-les-Nancy, France
| | - Isabelle Magnin Poull
- Institut Lorrain du Coeur et des Vaisseaux « Louis Mathieu », Cardiology Department, Electrophysiology Department, 54000 Vandoeuvre-les-Nancy, France
| | - Gabriel Laurent
- Centre Hospitalier Universitaire de Dijon, Cardiology Department, 21000 Dijon, France
| | - Christian de Chillou
- Institut Lorrain du Coeur et des Vaisseaux « Louis Mathieu », Cardiology Department, Electrophysiology Department, 54000 Vandoeuvre-les-Nancy, France
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Shah P, Koomson E. Sixty eight-year-old male with ischemic cardiomyopathy has this EKG finding. J Arrhythm 2018; 34:469-471. [PMID: 30167022 PMCID: PMC6111467 DOI: 10.1002/joa3.12076] [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] [Received: 03/04/2018] [Accepted: 05/02/2018] [Indexed: 12/02/2022] Open
Affiliation(s)
- Priyank Shah
- Department of Internal MedicineMedical College of Georgia ‐ Southwest Clinical CampusAlbanyGAUSA
- Department of CardiologyPhoebe Putney Memorial HospitalAlbanyGAUSA
| | - Edward Koomson
- Department of ElectrophysiologyPhoebe Putney Memorial HospitalAlbanyGAUSA
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Balakrishnan M, Chakravarthy VS, Guhathakurta S. Simulation of Cardiac Arrhythmias Using a 2D Heterogeneous Whole Heart Model. Front Physiol 2015; 6:374. [PMID: 26733873 PMCID: PMC4685512 DOI: 10.3389/fphys.2015.00374] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/18/2015] [Accepted: 11/23/2015] [Indexed: 01/11/2023] Open
Abstract
Simulation studies of cardiac arrhythmias at the whole heart level with electrocardiogram (ECG) gives an understanding of how the underlying cell and tissue level changes manifest as rhythm disturbances in the ECG. We present a 2D whole heart model (WHM2D) which can accommodate variations at the cellular level and can generate the ECG waveform. It is shown that, by varying cellular-level parameters like the gap junction conductance (GJC), excitability, action potential duration (APD) and frequency of oscillations of the auto-rhythmic cell in WHM2D a large variety of cardiac arrhythmias can be generated including sinus tachycardia, sinus bradycardia, sinus arrhythmia, sinus pause, junctional rhythm, Wolf Parkinson White syndrome and all types of AV conduction blocks. WHM2D includes key components of the electrical conduction system of the heart like the SA (Sino atrial) node cells, fast conducting intranodal pathways, slow conducting atriovenctricular (AV) node, bundle of His cells, Purkinje network, atrial, and ventricular myocardial cells. SA nodal cells, AV nodal cells, bundle of His cells, and Purkinje cells are represented by the Fitzhugh-Nagumo (FN) model which is a reduced model of the Hodgkin-Huxley neuron model. The atrial and ventricular myocardial cells are modeled by the Aliev-Panfilov (AP) two-variable model proposed for cardiac excitation. WHM2D can prove to be a valuable clinical tool for understanding cardiac arrhythmias.
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Affiliation(s)
- Minimol Balakrishnan
- Department of Biotechnology, Indian Institute of Technology MadrasChennai, India
| | | | - Soma Guhathakurta
- Department of Engineering Design, Indian Institute of Technology MadrasChennai, India
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Epstein AE, DiMarco JP, Ellenbogen KA, Estes NAM, Freedman RA, Gettes LS, Gillinov AM, Gregoratos G, Hammill SC, Hayes DL, Hlatky MA, Newby LK, Page RL, Schoenfeld MH, Silka MJ, Stevenson LW, Sweeney MO, Tracy CM, Epstein AE, Darbar D, DiMarco JP, Dunbar SB, Estes NAM, Ferguson TB, Hammill SC, Karasik PE, Link MS, Marine JE, Schoenfeld MH, Shanker AJ, Silka MJ, Stevenson LW, Stevenson WG, Varosy PD. 2012 ACCF/AHA/HRS focused update incorporated into the ACCF/AHA/HRS 2008 guidelines for device-based therapy of cardiac rhythm abnormalities: a report of the American College of Cardiology Foundation/American Heart Association Task Force on Practice Guidelines and the Heart Rhythm Society. J Am Coll Cardiol 2012; 61:e6-75. [PMID: 23265327 DOI: 10.1016/j.jacc.2012.11.007] [Citation(s) in RCA: 560] [Impact Index Per Article: 46.7] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 02/08/2023]
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Littmann L, Holshouser JW. Not so fast: acceleration-dependent or Mobitz type II second-degree AV block. Am J Med 2012; 125:967-70. [PMID: 22884178 DOI: 10.1016/j.amjmed.2012.06.011] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 04/20/2012] [Revised: 06/19/2012] [Accepted: 06/20/2012] [Indexed: 11/17/2022]
Affiliation(s)
- Laszlo Littmann
- Department of Internal Medicine, Carolinas Medical Center, Charlotte, NC 28232, USA.
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Kalra S, Hayaran N. Arrhythmias following spinal anesthesia for cesarean delivery - Is Wenckebach common? J Anaesthesiol Clin Pharmacol 2011; 27:541-3. [PMID: 22096293 PMCID: PMC3214565 DOI: 10.4103/0970-9185.86604] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/04/2022] Open
Abstract
Arrhythmias in pregnancy are common and may cause concern for the well-being of both mother and fetus. Generally, no previous history of heart disease is elicited and majority of the arrhythmias are benign. Bradycardia is commonly seen following subarachnoid block for cesarean section. However, the incidence of subsequent heart block is low. This case report highlights the occurrence of perioperative arrhythmias following sympathetic blockade in pregnant patients and their early detection by vigilant monitoring.
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Affiliation(s)
- Seema Kalra
- Department of Anaesthesiology and Critical Care, IGESI Hospital, Jhilmil, Delhi, India
| | - Nitin Hayaran
- Smt. Sucheta Kriplani Hospital and LHMC, New Delhi, India
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Kala R, Viitasalo MT, Toivonen L, Eisalo A. Ambulatory ECG recording in patients referred because of syncope or dizziness. ACTA MEDICA SCANDINAVICA. SUPPLEMENTUM 2009; 668:13-9. [PMID: 6963087 DOI: 10.1111/j.0954-6820.1982.tb08517.x] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 01/22/2023]
Abstract
Data are presented on patients referred for ambulatory ECG recording because of syncope or dizziness during a 2-year period. Of the 272 consecutive patients subjected to the recording, 107 (39.3%) had syncope or dizziness as the main indication for referral. Sixteen of these patients (14.9%) experienced the presenting symptom during the recording, and in 8 (50%) of these the simultaneous ECG finding was interpreted as causative. In patients who were symptom-free during the recording, sinus arrests exceeding 2.5 seconds seemed to be a valuable finding to support the cardiac aetiology of the syncopal symptoms, whereas the diagnostic value of second degree AV block with either Wenckebach or Mobitz II like patterns, as such, and of ventricular tachycardia remained mostly unsettled.
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Epstein AE, DiMarco JP, Ellenbogen KA, Estes NAM, Freedman RA, Gettes LS, Gillinov AM, Gregoratos G, Hammill SC, Hayes DL, Hlatky MA, Newby LK, Page RL, Schoenfeld MH, Silka MJ, Stevenson LW, Sweeney MO, Smith SC, Jacobs AK, Adams CD, Anderson JL, Buller CE, Creager MA, Ettinger SM, Faxon DP, Halperin JL, Hiratzka LF, Hunt SA, Krumholz HM, Kushner FG, Lytle BW, Nishimura RA, Ornato JP, Page RL, Riegel B, Tarkington LG, Yancy CW. ACC/AHA/HRS 2008 Guidelines for Device-Based Therapy of Cardiac Rhythm Abnormalities: a report of the American College of Cardiology/American Heart Association Task Force on Practice Guidelines (Writing Committee to Revise the ACC/AHA/NASPE 2002 Guideline Update for Implantation of Cardiac Pacemakers and Antiarrhythmia Devices) developed in collaboration with the American Association for Thoracic Surgery and Society of Thoracic Surgeons. J Am Coll Cardiol 2008; 51:e1-62. [PMID: 18498951 DOI: 10.1016/j.jacc.2008.02.032] [Citation(s) in RCA: 1098] [Impact Index Per Article: 68.6] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 01/13/2023]
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ACC/AHA/HRS 2008 Guidelines for device-based therapy of cardiac rhythm abnormalities. Heart Rhythm 2008; 5:e1-62. [PMID: 18534360 DOI: 10.1016/j.hrthm.2008.04.014] [Citation(s) in RCA: 196] [Impact Index Per Article: 12.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 04/16/2008] [Indexed: 01/27/2023]
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15
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Epstein AE, Dimarco JP, Ellenbogen KA, Estes NAM, Freedman RA, Gettes LS, Gillinov AM, Gregoratos G, Hammill SC, Hayes DL, Hlatky MA, Newby LK, Page RL, Schoenfeld MH, Silka MJ, Stevenson LW, Sweeney MO. ACC/AHA/HRS 2008 guidelines for Device-Based Therapy of Cardiac Rhythm Abnormalities: executive summary. Heart Rhythm 2008; 5:934-55. [PMID: 18534377 DOI: 10.1016/j.hrthm.2008.04.015] [Citation(s) in RCA: 267] [Impact Index Per Article: 16.7] [Reference Citation Analysis] [MESH Headings] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 04/11/2008] [Indexed: 11/16/2022]
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Shaw DB, Gowers JI, Kekwick CA, New KHJ, Whistance AWT. Is Mobitz type I atrioventricular block benign in adults? BRITISH HEART JOURNAL 2004; 90:169-74. [PMID: 14729789 PMCID: PMC1768048 DOI: 10.1136/hrt.2003.017806] [Citation(s) in RCA: 32] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 11/04/2022]
Abstract
OBJECTIVE To assess the need for pacing in adults with chronic Mobitz type I second degree atrioventricular block (Mobitz I). DESIGN Prospective study. SETTING District general hospital. PATIENTS 147 subjects aged > or = 20 years (age cohorts 20-44, 45-64, 65-79, and > or = 80) with chronic Mobitz I without second degree Mobitz II or third degree (higher degree) block on entry, seen from 1968 to 1993 and followed up to 30 June 1997. Sixty four had organic heart disease. The presence of symptomatic bradycardia was defined as highly likely in 47 patients (class 1); probable in 14 (class 2); and absent in 86 (class 3). INTERVENTIONS Pacemakers were implanted in 90 patients for the following indications: symptoms in 74 and prophylaxis in 16. MAIN OUTCOME MEASURES The main outcome measure was death, with conduction deterioration to higher degree block or symptomatic bradycardia the alternative measure. RESULTS Five year survival to death was reduced in unpaced patients relative to that expected for the normal population (overall mean (SD) 53.5 (6.7)% v 68.6%, p < 0.001; class 3, 54.4 (7.3)% v 70.1%, p < 0.001). Paced patients fared better than unpaced (overall (mean (SD) five year survival 76.3 (4.5)% v 53.5 (6.7)%, p = 0.0014; class 3, 87.2 (5.4)% v 54.4 (7.3)%, p = 0.020; and organic heart disease, 68.2 (7.6)% v 44.0 (9.9)%, p < or = 0.0014). There were no deaths in the < 45 cohort. Survival to first outcome (main or alternative) was further reduced to 31.7 (5.0)% in 102 patients unpaced initially and 34.2 (5.7)% in class 3. Only the 20-44 cohort and patients with sinus arrhythmia had > 50% survival. CONCLUSION Mobitz I block is not usually benign in patients > or = 45 years of age. Pacemaker implantation should be considered, even in the absence of symptomatic bradycardia or organic heart disease.
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Affiliation(s)
- D B Shaw
- Cardiac Department, Royal Devon and Exeter Hospital, Exeter, UK.
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Abstract
In this review, we discuss the various forms and causes of second-degree atrioventricular (AV) block and the reasons they remain poorly understood. Both type I and type II block characterize block of a single sinus P wave. Type I block describes visible, differing, and generally decremental AV conduction. Type II block describes what appears to be an all-or-none conduction without visible changes in the AV conduction time before and after the blocked impulse. Although the diagnosis of type II block is possible with an increasing sinus rate, absence of sinus slowing is an important criterion of type II block because a vagal surge (generally a benign condition) can cause simultaneous sinus slowing and AV nodal block, which can superficially resemble type II block. The diagnosis of type II block cannot be established if the first postblock P wave is followed by a shortened PR interval or is not discernible. A pattern resembling a narrow QRS type II block in association with an obvious type I structure in the same recording (e.g., Holter) effectively rules out type II block because the coexistence of both types of narrow QRS block is exceedingly rare. Concealed His bundle or ventricular extrasystoles confined to the specialized conduction system without myocardial penetration and depolarization can produce electrocardiographic patterns that mimic type I and/or type II block (pseudo-AV block). All correctly defined type II blocks are infranodal. A narrow QRS type I block is almost always AV nodal, whereas a type I block with bundle branch block barring acute myocardial infarction is infranodal in 60% to 70% of cases. A 2:1 AV block cannot be classified in terms of type I or type II block, but it can be nodal or infranodal. Infranodal blocks require pacing regardless of form or symptoms. The widespread use of numerous disparate definitions of type II block appears primarily responsible for many of the problems surrounding second-degree AV block. Adherence to the correct definitions provides a logical and simple framework for clinical evaluation.
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Affiliation(s)
- S S Barold
- Electrophysiology Institute, Broward General Hospital, Ft Lauderdale, Fla., USA.
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Shen CL, Ho YY, Hung YC, Chen PL. Arrhythmias during spinal anesthesia for Cesarean section. Can J Anaesth 2000; 47:393-7. [PMID: 10831193 DOI: 10.1007/bf03018966] [Citation(s) in RCA: 32] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/20/2022] Open
Abstract
PURPOSE Spinal block has long been considered a safe anesthesia technique for surgery. However, severe bradycardia, cardiac arrest, and other arrhythmias during spinal anesthesia have been reported and the incidence of intraoperative arrhythmias is not well established. In this study the incidence of arrhythmias during spinal anesthesia was determined. METHODS We studied 254 healthy women undergoing Cesarean section under spinal anesthesia prospectively. Spinal anesthesia with 10 mg bupivacaine mixed with 0.2 mg morphine was performed at the L3-4 interspace. Intraoperative arrhythmias were recorded and verified later by a cardiologist. RESULTS First degree atrioventricular block developed in nine patients (3.5%), second degree atrioventricular block in nine (3.5%), severe bradycardia (heart rate < 50 beats x min(-1)) in seventeen (6.7%), multiple VPC in three (1.2%). The height and weight of patients with severe bradycardia, multiple VPCs, or atrioventricular block were not different from those of the other patients. However, the age of patients in the potentially dangerous arrhythmias group was greater than that in the other group (P = 0.006). CONCLUSION The incidence of arrhythmias as well as hypotension during spinal anesthesia for Cesarean section was higher than expected. Although most of these arrhythmias were transient and recovered spontaneously, they might unexpectedly occur and sometimes need immediate and prompt treatment. It is necessary to remain vigilant during spinal anesthesia for Cesarean section and careful monitoring of these patients is warranted, especially in older parturients.
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Affiliation(s)
- C L Shen
- Department of Anesthesiology, Ton Yen General Hospital, Chu Pei, Hsin Chu, Taiwan.
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Al-Sheikh T, Zipes DP. Guidelines for Competitive Athletes with Arrhythmias. DEVELOPMENTS IN CARDIOVASCULAR MEDICINE 2000. [DOI: 10.1007/978-94-017-0789-3_9] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 12/13/2022]
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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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Pinski SL, Tchou PJ, Trohman RG. Paradoxical shortening of the second PR interval during 3:2 atrioventricular nodal block. J Cardiovasc Electrophysiol 1996; 7:1091-4. [PMID: 8930742 DOI: 10.1111/j.1540-8167.1996.tb00486.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: 02/03/2023]
Abstract
A patient with 3:2 second-degree AV block after acute inferior wall myocardial infarction showed consistent PR interval shortening on the second conducted beat in each periodicity. Intracardiac electrophysiologic evaluation revealed that the site of block was nodal. A typical Wenckebach pattern with prolongation of the AH interval was noted. The shorter PR resulted from a paradoxical shortening of the HV interval in the second beat, most likely due to supernormal conduction in the setting of concomitant trifascicular disease.
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Affiliation(s)
- S L Pinski
- Department of Cardiology, Cleveland Clinic Foundation, OH 44195, USA
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25
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Ritchie JL. ACC/AHA Guidelines for Clinical Intracardiac Electrophysiological and Catheter Ablation Procedures. J Cardiovasc Electrophysiol 1995. [DOI: 10.1111/j.1540-8167.1995.tb00443.x] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 11/27/2022]
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Zipes DP, DiMarco JP, Gillette PC, Jackman WM, Myerburg RJ, Rahimtoola SH, Ritchie JL, Cheitlin MD, Garson A, Gibbons RJ. Guidelines for clinical intracardiac electrophysiological and catheter ablation procedures. A report of the American College of Cardiology/American Heart Association Task Force on Practice Guidelines (Committee on Clinical Intracardiac Electrophysiologic and Catheter Ablation Procedures), developed in collaboration with the North American Society of Pacing and Electrophysiology. J Am Coll Cardiol 1995; 26:555-73. [PMID: 7608464 DOI: 10.1016/0735-1097(95)80037-h] [Citation(s) in RCA: 156] [Impact Index Per Article: 5.4] [Reference Citation Analysis] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 01/26/2023]
Affiliation(s)
- D P Zipes
- Educational Services, American College of Cardiology, Bethesda, Maryland 20814-1699, USA
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Abstract
Acute atrioventricular (AV) block occurs frequently in patients with myocardial infarction. Atrioventricular block is also a common manifestation of sclerodegenerative conduction system disease. Occasionally, heart block results from drug toxicity, hyperkalemia, cardiac valvular calcification, myocarditis, or infiltrative cardiomyopathy. Second-degree AV block is a form of "incomplete" heart block, in which some, but not all, atrial beats are blocked before reaching the ventricles. Mobitz type II second-degree block is an old term, which refers to periodic atrioventricular block with constant PR intervals in the conducted beats. The distinction between type II and type I block is descriptive; of greater importance to the clinician is the anatomic site of the block and the prognosis. In Mobitz type II block the site is almost always below the AV node; in Mobitz type I block the site is usually within the AV node. Type II AV block is more likely to progress to complete heart block and Stokes-Adams arrest. In most cases of second-degree heart block, including cases of 2:1 conduction, it is possible to determine the site of the AV block (intranodal or infranodal) using information about the age of the patient, the clinical setting, and the width of the QRS complex on the surface electrocardiogram. Second-degree atrioventricular block must be distinguished from other "causes of pauses." Nonconducted premature atrial contractions and atrial tachycardia with block are common conditions, which may mimic second-degree AV block.
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Affiliation(s)
- J M Wogan
- Department of Emergency Medicine, Johns Hopkins Hospital, Johns Hopkins University School of Medicine, Baltimore, Maryland
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Cianfrocca C, Pelliccia F, Nigri A, Critelli G. Resting and ambulatory ECG predictors of mode of death in dilated cardiomyopathy. J Electrocardiol 1992; 25:295-303. [PMID: 1402515 DOI: 10.1016/0022-0736(92)90035-x] [Citation(s) in RCA: 25] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/26/2022]
Abstract
With the purpose of verifying whether the electrocardiogram (ECG) pattern alone can predict the mode of death in dilated cardiomyopathy, data from 12-lead ECGs and 48-hour arrhythmia monitoring were evaluated in 67 patients with dilated cardiomyopathy. During a mean follow-up period of 3 +/- 2 years, death from congestive heart failure occurred in 18 patients (27%), whereas 10 (15%) died suddenly (NS). Multivariate analysis showed that left bundle branch block (p < 0.001) and left atrial enlargement (p < 0.001) were independently related to death from congestive heart failure. Ventricular arrhythmias of Lown grade 4A or 4B (p < 0.001) and repolarization time, as assessed by QTc-QRS interval (p < 0.05), were independent predictors of sudden death. It is concluded that ECG features alone may be helpful for risk factor characterization of dilated cardiomyopathy patients, provided that multiple ECG criteria are utilized at time of diagnosis.
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Affiliation(s)
- C Cianfrocca
- Department of Cardiology, University of Rome La Sapienza, Italy
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29
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Kupfer JM, Kligfield P. A generalized description of Wenckebach behavior with analysis of determinants of ventricular cycle-length variation during ambulatory electrocardiography. Am J Cardiol 1991; 67:981-6. [PMID: 2018017 DOI: 10.1016/0002-9149(91)90171-g] [Citation(s) in RCA: 7] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 12/29/2022]
Abstract
Although variation in ventricular cycle length during Wenckebach-type second-degree atrioventricular block traditionally has been explained by the direction of incremental change in PR lengthening preceding the blocked complex, changing PP intervals can also affect Wenckebach periodicity. A generalized algebraic solution was derived to define changing ventricular cycle length as a function of both changing PP and changing incremental PR interval behavior in Wenckebach block. Based on this solution, the determinants of cycle-length variation were examined for 65 episodes of Wenckebach block detected by ambulatory electrocardiography in 51 patients. As previously demonstrated, only 20% (13 of 65) of Wenckebach episodes were characterized by the "classic" shortening of RR intervals; in contrast, ventricular cycle length increased in 57% (37 of 65) and remained constant in 23% (15 of 65) of cases. Algebraic analysis of these episodes revealed that the direction of ventricular cycle-length change preceding the blocked complex was primarily determined by the direction of change of incremental PR intervals in only 35% (23 of 65) of Wenckebach episodes; RR change was governed by the direction of change of preceding PP intervals in 34% (22 of 65) and by equal change of PP and incremental PR intervals in 31% (20 of 65) of these episodes. Both inverse and concordant relationships between changing RP and PR intervals were primarily determined by the direction of PP variation during in vivo Wenckebach block. These data confirm that classic Wenckebach block is less common than "atypical" Wenckebach periodicity and demonstrate that RR variation in Wenckebach block is governed by the changing PP interval as often as by the changing incremental PR interval.
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Affiliation(s)
- J M Kupfer
- Department of Medicine, New York Hospital, Cornell Medical Center, New York 10021
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30
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Pelliccia F, Cianfrocca C, Cristofani R, Romeo F, Reale A. Electrocardiographic findings in patients with hypertrophic cardiomyopathy. Relation to presenting features and prognosis. J Electrocardiol 1990; 23:213-22. [PMID: 2384727 DOI: 10.1016/0022-0736(90)90159-y] [Citation(s) in RCA: 7] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/31/2022]
Abstract
The relation of ECG findings to presenting features and prognosis was evaluated in 125 consecutive patients with hypertrophic cardiomyopathy (HC). Seventy-nine men and 46 women (mean age, 34 +/- 7 years) were studied since 1970. Most ECG features were similar in patients with and without a left ventricular outflow tract gradient. Those with obstruction had a higher prevalence of left ventricular hypertrophy according to ECG voltage criteria (54% vs. 28%, p less than 0.01), whereas higher grade ventricular arrhythmias were more common in patients without an outflow gradient (20% vs. 7%, p less than 0.05). The prevalence of ECG abnormalities was also similar in younger (less than or equal to 14 years) and older patients (greater than 14 years), and only repolarization abnormalities were more frequently detected in the older age group (56% vs. 32%, p less than 0.025). Stratification of patients according to the clinical state revealed that those who had moderate to severe functional limitation had a higher prevalence of atrial fibrillation than asymptomatic or mildly symptomatic patients (24% vs. 1%, p less than 0.001). There were no significant differences in most hemodynamic variables among patients dichotomized according to any specific ECG abnormality. Only patients with atrial fibrillation had significantly higher right ventricular end-diastolic pressure (10 +/- 7 vs. 6 +/- 4 mmHg, p less than 0.01), lower systolic index (22 +/- 8 vs. 37 +/- 15 ml/m2; beat, p less than 0.02) and lower ejection fraction (53 +/- 8 vs. 64 +/- 10%, p less than 0.001) than those in sinus rhythm.(ABSTRACT TRUNCATED AT 250 WORDS)
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Affiliation(s)
- F Pelliccia
- Department of Cardiology, University of Rome, La Sapienza, Italy
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31
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Guidelines for clinical intracardiac electrophysiologic studies. A report of the American College of Cardiology/American Heart Association Task Force on Assessment of Diagnostic and Therapeutic Cardiovascular Procedures (Subcommittee to Assess Clinical Intracardiac Electrophysiologic Studies). J Am Coll Cardiol 1989; 14:1827-42. [PMID: 2584574 DOI: 10.1016/0735-1097(89)90040-5] [Citation(s) in RCA: 39] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 01/01/2023]
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32
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Schweitzer P. The electrocardiographic manifestation of combined AV nodal Wenckebach periodicity and reentry. Pacing Clin Electrophysiol 1989; 12:1846-50. [PMID: 2481279 DOI: 10.1111/j.1540-8159.1989.tb01874.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: 01/01/2023]
Abstract
Presented are three patients with Wenckebach type second degree AV block that was complicated with AV nodal reentry producing different arrhythmias. The common presentation of manifest AV nodal reentry is an incomplete Wenckebach periodicity, whereby the retrograde impulse interrupts the Wenckebach cycle; rarely, the retrograde impulse initiates an AV junctional reentrant tachycardia. The documentation of concealed AV nodal reentry is more difficult and should be considered if there is a sudden increase of the PR interval in the Wenckebach cycle.
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Affiliation(s)
- P Schweitzer
- Department of Medicine, Bronx Veterans Administration Medical Center, NY 10468
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33
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Silver MD, Goldschlager N. Temporary transvenous cardiac pacing in the critical care setting. Chest 1988; 93:607-13. [PMID: 3277806 DOI: 10.1378/chest.93.3.607] [Citation(s) in RCA: 24] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/05/2023] Open
Affiliation(s)
- M D Silver
- Division of Cardiology, San Francisco General Hospital 94110
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34
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Lange HW, Ameisen O, Mack R, Moses JW, Kligfield P. Prevalence and clinical correlates of non-Wenckebach, narrow-complex second-degree atrioventricular block detected by ambulatory ECG. Am Heart J 1988; 115:114-20. [PMID: 3336966 DOI: 10.1016/0002-8703(88)90526-1] [Citation(s) in RCA: 17] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 01/05/2023]
Abstract
Among 113 patients with transient, narrow-complex second-degree atrioventricular (AV) block detected by ambulatory ECG, there were 20 with non-Wenckebach behavior. Based on the presence or absence of PR interval shortening after single blocked complexes, patients with narrow-complex non-Wenckebach patterns could be separated into a pseudo-Mobitz II group of 16 patients (greater than or equal to 20 msec of PR shortening after the blocked complex) and a classic Mobitz II group of four patients (constant PR interval). These groups had additional distinct ECG and clinical features. Patients with the pseudo-Mobitz II pattern had a 44% prevalence of associated Wenckebach block during the same ambulatory recording, whereas Wenckebach behavior did not occur in patients with classic Mobitz II block. Pseudo-Mobitz II block occurred at significantly longer cycle lengths (876 vs 585 msec) and with significantly longer PR intervals (225 vs 165 msec) preceding the blocked complex than did classic Mobitz II block. Syncope was the presenting symptom in 38% of patients with pseudo-Mobitz II block and in all patients with classic Mobitz II block. Patients with pseudo-Mobitz II block had a 56% prevalence of associated coronary disease and a 44% prevalence of congestive heart failure; the mortality rate was 38% in this group over 4 years of follow-up, but in all instances death was due to associated disease rather than to conduction itself. In contrast, patients with classic Mobitz II block had hypertensive or valvular disease but no evidence of coronary disease or congestive failure; all are alive with pacemakers after 3 years of follow-up.(ABSTRACT TRUNCATED AT 250 WORDS)
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Affiliation(s)
- H W Lange
- Department of Medicine, New York Hospital-Cornell Medical Center, NY
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35
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Falk RH. Pseudoparadoxic effect of atropine and carotid sinus massage on atrioventricular conduction in acute myocardial infarction. Chest 1986; 90:601-3. [PMID: 3757570 DOI: 10.1378/chest.90.4.601] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/07/2023] Open
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36
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DiCarlo LA, Morady F. Evaluation of the Patient with Syncope. Cardiol Clin 1985. [DOI: 10.1016/s0733-8651(18)30648-9] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 10/28/2022]
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Abstract
Two hundred and 14 patients with chronic second degree heart block were seen and followed up in the Devon Heart Block and Bradycardia Survey between 1968 and 1982. The patients were divided into three groups according to the type of block. In group 1 there were 77 patients with Mobitz type I block (mean age 69 years), in group 2, 86 patients with Mobitz type II block (mean age 74 years), and in group 3, 51 with 2:1 or 3:1 block (mean age 75 years). The five year survival was similar in all groups, being 57%, 61%, and 53% in groups 1, 2, and 3 respectively. The presence or absence of bundle branch block did not appear to influence prognosis. In particular, patients in group 1 without bundle branch block did not fare any better than those in group 2 both with and without bundle branch block. One hundred and three of the patients were fitted with pacemakers, the proportion being greatest in group 2. In each group a significantly larger number of paced patients survived than unpaced. The five year survival for all the paced patients in the study was 78% compared with 41% for the unpaced. Since the paced patients were slightly younger than the unpaced two age matched groups of 74 patients each were selected from the paced and unpaced patients, but the five year survival of those paced was still significantly better. It is concluded that in the patients in the present study chronic Mobitz type I block has a similar prognosis to that of Mobitz type II block. Unpaced patients with both types did very badly, whereas those fitted with pacemakers had a five year survival similar to that expected for the normal population. These results refute the benign reputation of chronic Mobitz type I block and imply that patients with this condition should be considered for pacemaker implantation on similar criteria to those adopted for patients with higher degrees of block.
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38
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Jalife J. The sucrose gap preparation as a model of AV nodal transmission: are dual pathways necessary for reciprocation and AV nodal "echoes"? Pacing Clin Electrophysiol 1983; 6:1106-22. [PMID: 6195631 DOI: 10.1111/j.1540-8159.1983.tb04449.x] [Citation(s) in RCA: 36] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 01/18/2023]
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39
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40
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Mangiardi LM, Bonamini R, Conte M, Gaita F, Orzan F, Presbitero P, Brusca A. Bedside evaluation of atrioventricular block with narrow QRS complexes: usefulness of carotid sinus massage and atropine administration. Am J Cardiol 1982; 49:1136-45. [PMID: 7064840 DOI: 10.1016/0002-9149(82)90037-6] [Citation(s) in RCA: 33] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 01/23/2023]
Abstract
Second-degree intra-His bundle block is frequently of type I (Wenckebach periods) or 2:1. In this situation, the surface electrocardiogram does not permit distinction between intranodal (atrioventricular [A-V] and subnodal (intra-His) block. This study examined the value of bedside carotid sinus massage and atropine administration in diagnosing the site of block from the standard electrocardiogram in subjects with chronic A-V block and narrow QRS complexes. Fifteen patients had intra-His bundle block and 10 had intranodal block. The combination of two tests correctly located the site of block in 22 subjects, and was noncontributory in 3. Thirteen of the 15 intra-His bundle blocks and 9 of the 10 intranodal blocks were properly identified; in three cases the results were nondiagnostic, but no wrong diagnoses were made. The noninvasive bedside method of carotid sinus massage and the use of atropine permit both the localization and the determination of the type of block in the majority of cases of second degree A-V block and narrow QRS complexes. In a proper clinical context they can obviate the need for invasive electrophysiologic studies.
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42
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Viitasalo MT, Kala R, Eisalo A. Ambulatory electrocardiographic recording in endurance athletes. BRITISH HEART JOURNAL 1982; 47:213-20. [PMID: 7059398 PMCID: PMC481124 DOI: 10.1136/hrt.47.3.213] [Citation(s) in RCA: 119] [Impact Index Per Article: 2.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 01/23/2023]
Abstract
Data from ambulatory electrocardiographic recording in 35 highly trained endurance athletes and in 35 non-athletic controls of similar ages are given. The minimal, mean hourly, and maximal heart rates were significantly lower in the athletes. Thirteen athletes (37 . 1%) but only two controls (5 . 7%) had sinus pauses exceeding 2 . 0 seconds. First degree atrioventricular block was observed in 13 athletes (37 . 1%) and five controls (14 . 3%), second degree Wenckebach type block in eight athletes (22 . 9%) and two controls (5 . 7%), and second degree block with Mobitz II-like pattern in three athletes (8 . 6%) and no control. All athletes with Mobitz II-type pattern also had first degree and Wenckebach-type second degree atrioventricular block. The behavior of sinus rate on development of atrioventricular block varied, not only interindividually but also intraindividually, from absence of change to an increase or decrease in most subjects in both study groups. A decrease in sinus rate on appearance of atrioventricular block was found constantly in only two athletes and one control. Atrioventricular dissociation with junctional rhythm occurred in seven athletes (20%) and with ventricular rhythm in one athlete. Neither of these phenomena was seen in the group of controls. The athletes had slightly fewer ventricular extrasystoles than controls, and no athlete had ventricular tachycardia, whereas two controls had ventricular tachycardia.
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43
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44
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45
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46
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Abstract
A 61-year-old man presented with symptomatic 2 degree Mobitz II AV block in association with bifascicular block. Ventricular pacing resulted in temporary depression of AV conduction. The extent of pacing-induced AV block varied directly with the duration and rate of ventricular pacing. Intracardiac recordings proved that the site of spontaneous and pacing-induced AV block was distal to the His bundle. Possible mechanisms by which this phenomenon may arise and several implications of practical importance are discussed.
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47
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McKenna WJ, Rowland E, Davies J, Krikler DM. Failure to predict development of atrioventricular block with electrophysiological testing supplemented by ajmaline. Pacing Clin Electrophysiol 1980; 3:666-9. [PMID: 6161347 DOI: 10.1111/j.1540-8159.1980.tb05569.x] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 01/18/2023]
Abstract
Electrophysiological tests supplemented by pharmacological stress of atrioventricular conduction with ajamaline failed to predict the development of atrioventricular block in a patient with bifascicular block and no organic heart disease.
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48
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Scott O, Williams GJ, Fiddler GI. Results of 24 hour ambulatory monitoring of electrocardiogram in 131 healthy boys aged 10 to 13 years. BRITISH HEART JOURNAL 1980; 44:304-8. [PMID: 7426187 PMCID: PMC482402 DOI: 10.1136/hrt.44.3.304] [Citation(s) in RCA: 93] [Impact Index Per Article: 2.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 01/25/2023]
Abstract
Ambulatory monitoring of the electrocardiogram was performed in 131 healthy boys aged between 10 and 13 years for two consecutive periods of 24 hours. When awake the maximal heart rates ranged from 100 to 200 and the minimal from 45 to 80 beats per minute. During sleep maximal rates were 60 to 110 beats and minimal rates 30 to 70 beats per minute. Sinus arrhythmia was seen in every boy and in 36 (27.5%) no other changes were found. Sinuatrial block, Mobitz type I, was not seen. Sinuatrial block, Mobitz type II, occurred twice only. Complete sinuatrial block occurred in 8.4 per cent, never lasted more than one cycle, and was always followed by a junctional beat. First degree atrioventricular block occurred in 8.4 per cent and Mobitz type I atrioventricular block in 10.7 per cent. Premature beats were always single, atrial in 13 per cent, ventricular in 26 per cent, and except in two boys were never more than four in 24 hours. There were no episodes of ventricular or supraventricular tachycardia. Changes in P wave morphology were common and slow junctional rhythm occurred in 13 per cent during sleep.
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