Close
New

Medscape is available in 5 Language Editions – Choose your Edition here.

 

Pediatric Third-Degree Acquired Atrioventricular Block Workup

  • Author: Charles I Berul, MD; Chief Editor: Howard S Weber, MD, FSCAI  more...
 
Updated: Dec 09, 2015
 

Approach Considerations

Lyme disease is diagnosed by its clinical picture and serologic confirmation. Serologic test findings may be negative during the first several weeks, but most patients have a positive antibody response to B burgdorferi by enzyme-linked immunoabsorbent assay (ELISA). In addition, B burgdorferi may be cultured from skin lesions during the acute phase or from skin lavage as it has been recently described.

Diagnosis of acute Chagas disease is made by microscopic examination of fresh anticoagulated blood to visualize the parasites. Whenever this technique is unsuccessful, xenodiagnosis can yield positive test results in virtually all patients with acute Chagas disease and in half of those with chronic disease. In this technique, uninfected reduviids feed on the patient's blood and, 30 days later, their intestinal contents are examined for the presence of parasites. In case of chronic Chagas disease, serologic tests to detect antibodies against T cruzi antigens, such as complement fixation and ELISA, are used.

The diagnosis of Reiter syndrome is mainly clinical, because no specific laboratory tests are used for this entity. However, nonspecific findings include elevated erythrocyte sedimentation rate (ESR) and C-reactive protein (CRP), elevated immunoglobulin A (IgA), mild normochromic and normocytic anemia, and absent rheumatoid factor (RF) and antinuclear antibodies (ANAs).

Definitive diagnosis of diphtheria is made by isolation of C diphtheriae from local lesions.

Perform laboratory testing for lymphoma, amyloidosis, sarcoidosis, and digoxin as indicated.

Antenatal diagnosis of third-degree AV block requires careful maternal-fetal management and monitoring with ultrasonography and echocardiography.[27] Delivery is recommended at a tertiary care center with a multidisciplinary team that includes perinatal care and an association with a pediatric cardiology center.[27]

Next

Electrophysiologic Studies

Intracardiac electrophysiologic (EP) studies are usually not necessary for most patients with AV block; however, when performed, the EP results can be used to determine whether the AV block is above, within, or below the bundle of His.

EP studies are not required for patients with complete AV block and symptoms such as dizziness, syncope, or congestive heart failure. These patients require permanent pacemaker therapy. Indications for pacing are outlined in detail in the ACC/AHA/HRS consensus document.

Infra-His AV block

Patients with infra-His atrioventricular (AV) block typically have a much slower ventricular rate (ie, heart rate) and require permanent pacemaker therapy to avoid asystole, ventricular arrhythmia, syncope, or symptoms.

The block is located in the AV node above the His bundle when the ventricular depolarization is preceded by a His depolarization, which, in turn, is not coupled to the atrial depolarization.

The block is within the His bundle if the His bundle depolarization is preceded by an atrial depolarization, and a second His bundle depolarization precedes a ventricular depolarization.

The block is below the His bundle when the His depolarization follows an atrial depolarization but does not precede a ventricular depolarization.

Junctional/ventricular pacing

Adequacy of the junctional or ventricular pacemaker can be evaluated by pacing the ventricles at different rates for 30-60 seconds, stopping abruptly, and measuring their recovery time (ie, from the last paced ventricular beat to the first spontaneous ventricular beat). A junctional or ventricular recovery time exceeding 3 seconds in children is abnormal and has been associated with risk for sudden death.

See the following examples of intracardiac EP studies.

This is an example of a normal finding on intracar This is an example of a normal finding on intracardiac electrophysiologic (EP) study. The surface electrocardiogram (ECG) is represented in different colors, with its corresponding intervals (ie, PR, QT) on top. A catheter with several electrodes is placed inside the heart, close to the superior vena cava–right atrial junction. This catheter records the sinoatrial node (SN) activity and is depicted here as the high-right atrial (HRA) deflection. Beneath the HRA intracardiac electrogram is the His-bundle intracardiac electrogram, which is recorded by the electrodes of a second catheter placed across the posterior aspect of the tricuspid valve. The His-bundle electrogram provides the most information about atrioventricular (AV) conduction. Three main deflections are present, with 2 intervals: (1) the A deflection corresponds to the activation of the low-right atrium, (2) the H deflection corresponds to the activation of the His-bundle before its branching into the Purkinje system, and (3) the V deflection corresponds to the activation of the proximal portion of the right ventricle. The atrium-His (A-H) interval represents the conduction time through the AV node. It shows the time elapsed between the activation of the low-right atrium (A) and the activation of the His-bundle (H), ranging normally from 50-120 milliseconds. The His-ventricle (H-V) interval is measured from the beginning of the H deflection to the beginning of the V deflection and represents the conduction time through the His-Purkinje system (normally 35-55 ms). Disease in the AV node prolongs the A-H interval, whereas disease in the distal conducting system prolongs the H-V interval.
This is a Mobitz type II second-degree atrioventri This is a Mobitz type II second-degree atrioventricular (AV) block. The surface electrocardiograph (ECG) shows normal PR intervals and a P wave that is not followed by a QRS (in this graphic, the first P wave does not conduct through the AV node). The intracardiac electrogram shows no His deflection (H) after the blocked A deflection. In this case, the escape rhythm originates higher in the AV node at a rate of 40-50 beats per minute and is fairly reliable. However, patients may report symptoms of bradycardia such as dizziness, fatigue, and syncope. Because this type of AV block may progress to complete or third-degree AV block, patients should be monitored regularly even in the absence of symptoms.
This is a Mobitz type II second-degree atrioventri This is a Mobitz type II second-degree atrioventricular (AV) block that may likely progress to a third-degree, or complete, AV block. The difference from the previous image is that, in this case, a His (H) deflection is present after the A deflection (the atrium-His [A-H] interval is maintained); however, no ventricle (V) deflection is present after the first H deflection. Therefore, in this case, the escape rhythm is slower than in the intracardiac electrophysiologic study of the patient in the previous image (< 40/min) and less reliable. This patient is more likely to receive a pacemaker because of the higher incidence of sudden death secondary to prolonged asystole.
Previous
 
 
Contributor Information and Disclosures
Author

Charles I Berul, MD Professor of Pediatrics and Integrative Systems Biology, George Washington University School of Medicine; Chief, Division of Cardiology, Children's National Medical Center

Charles I Berul, MD is a member of the following medical societies: American Academy of Pediatrics, Heart Rhythm Society, Cardiac Electrophysiology Society, Pediatric and Congenital Electrophysiology Society, American College of Cardiology, American Heart Association, Society for Pediatric Research

Disclosure: Received grant/research funds from Medtronic for consulting.

Coauthor(s)

Peter P Karpawich, MD Professor of Pediatric Medicine, Department of Pediatrics (Cardiology), Wayne State University School of Medicine; Director, Cardiac Electrophysiology and Pacemaker Services, Children's Hospital of Michigan

Peter P Karpawich, MD is a member of the following medical societies: American Academy of Pediatrics, Heart Rhythm Society, Pediatric and Congenital Electrophysiology Society, American College of Cardiology, American Heart Association, Michigan State Medical Society

Disclosure: Nothing to disclose.

Chief Editor

Howard S Weber, MD, FSCAI Professor of Pediatrics, Section of Pediatric Cardiology, Pennsylvania State University College of Medicine; Director of Interventional Pediatric Cardiology, Penn State Hershey Children's Hospital

Howard S Weber, MD, FSCAI is a member of the following medical societies: American Academy of Pediatrics, American College of Cardiology, Society for Cardiovascular Angiography and Interventions

Disclosure: Received income in an amount equal to or greater than $250 from: St. Jude Medical.

Acknowledgements

Alvin J Chin, MD Professor of Pediatrics, University of Pennsylvania School of Medicine; Attending Physician, Cardiology Division, Children's Hospital of Philadelphia

Alvin J Chin, MD, is a member of the following medical societies: American Association for the Advancement of Science, American Heart Association, and Society for Developmental Biology

Disclosure: Nothing to disclose.

M Silvana Horenstein, MD Assistant Professor, Department of Pediatrics, University of Texas Medical School at Houston; Medical Doctor Consultant, Legacy Department, Best Doctors, Inc

M Silvana Horenstein, MD is a member of the following medical societies: American Academy of Pediatrics, American College of Cardiology, and American Medical Association

Disclosure: Nothing to disclose.

Mary L Windle, PharmD Adjunct Associate Professor, University of Nebraska Medical Center College of Pharmacy; Editor-in-Chief, Medscape Drug Reference

Disclosure: Nothing to disclose.

References
  1. Anderson RH, Janse MJ, van Capelle FJ, et al. A combined morphological and electrophysiological study of the atrioventricular node of the rabbit heart. Circ Res. 1974 Dec. 35(6):909-22. [Medline].

  2. Dobrzynski H, Nikolski VP, Sambelashvili AT, et al. Site of origin and molecular substrate of atrioventricular junctional rhythm in the rabbit heart. Circ Res. 2003 Nov 28. 93(11):1102-10. [Medline].

  3. Bonatti V, Agnetti A, Squarcia U. Early and late postoperative complete heart block in pediatric patients submitted to open-heart surgery for congenital heart disease. Pediatr Med Chir. 1998 May-Jun. 20(3):181-6. [Medline].

  4. Paech C, Dahnert I, Kostelka M, Mende M, Gebauer R. Association of temporary complete AV block and junctional ectopic tachycardia after surgery for congenital heart disease. Ann Pediatr Cardiol. 2015 Jan-Apr. 8 (1):14-9. [Medline].

  5. Carminati M, Butera G, Chessa M, Drago M, Negura D, Piazza L. Transcatheter closure of congenital ventricular septal defect with Amplatzer septal occluders. Am J Cardiol. 2005 Dec 19. 96(12A):52L-58L. [Medline].

  6. Berhouet M, Casset-Senon D, Machet MC, et al. Conduction defects as the presenting feature of sarcoidosis or observed during the course of the disease: regression with corticoid steroid therapy. Arch Mal Coeur Vaiss. 2003 Jun. 96(6):677-82. [Medline].

  7. Konno T, Shimizu M, Ino H, et al. A rare type of alternating bundle branch block in a patient with cardiac sarcoidosis--a case report. Angiology. 2005 Jan-Feb. 56(1):115-7. [Medline].

  8. Umetani K, Ishihara T, Yamamoto K, et al. Successfully treated complete atrioventricular block with corticosteroid in a patient with cardiac sarcoidosis: usefulness of gallium-67 and thallium-201 scintigraphy. Intern Med. 2000 Mar. 39(3):245-8. [Medline].

  9. Ford SE. Congenital cystic tumors of the atrio-ventricular node: successful demonstration by an abbreviated dissection of the conduction system. Cardiovasc Pathol. 1999 Jul-Aug. 8(4):233-7. [Medline].

  10. Evans DW, Stovin PG. Fatal heart block due to mesothelioma of the atrioventricular node. Br Heart J. 1986 Dec. 56(6):572-4. [Medline].

  11. Kawano H, Okada R, Kawano Y, et al. Mesothelioma in the atrioventricular node. Case report. Jpn Heart J. 1994 Mar. 35(2):255-61. [Medline].

  12. Lie JT, Lufschanowski R, Erickson EE. Heterotopic epithelial replacement (so-called "mesothelioma") of the atrioventricular node, congenital heart block, and sudden death. Am J Forensic Med Pathol. 1980 Jun. 1(2):131-7. [Medline].

  13. Strauss WE, Asinger RW, Hodges M. Mesothelioma of the AV node: potential utility of pacing. Pacing Clin Electrophysiol. 1988 Sep. 11(9):1296-8. [Medline].

  14. Subramanian R, Flygenring B. Mesothelioma of the atrioventricular node and congenital complete heart block. Clin Cardiol. 1989 Aug. 12(8):469-72. [Medline].

  15. Thorgeirsson G, Liebman J. Mesothelioma of the AV node. Pediatr Cardiol. 1983 Jul-Sep. 4(3):219-23. [Medline].

  16. Ozyuncu N, Sahin M, Altin T, Karaoguz R, Guldal M, Akyurek O. Cardiac metastasis of malignant melanoma: a rare cause of complete atrioventricular block. Europace. 2006 Jul. 8(7):545-8. [Medline].

  17. Legoux B, Jegou B, Litoux P, Dreno B. [Cardiac metastasis of melanoma disclosed by tamponade]. Ann Dermatol Venereol. 1996. 123(6-7):393-4. [Medline].

  18. Fujisaki J, Tanaka T, Kato J, et al. Primary cardiac lymphoma presenting clinically as restrictive cardiomyopathy. Circ J. 2005 Feb. 69(2):249-52. [Medline].

  19. Musso P, Ronzani G, Ravera A, et al. Primary cardiac lymphoma presenting with complete atrioventricular block. Case report and review of the literature. Ital Heart J Suppl. 2002 Oct. 3(10):1047-50. [Medline].

  20. Lim HE, Pak HN, Kim YH. Acute myocarditis associated with cardiac amyloidosis manifesting as transient complete atrioventricular block and slow ventricular tachycardia. Int J Cardiol. 2006 May 24. 109(3):395-7. [Medline].

  21. Ogano M, Takano H, Fukuma N, et al. Sudden death in a case of cardiac amyloidosis immediately after pacemaker implantation for complete atrioventricular block. J Nippon Med Sch. 2005 Oct. 72(5):285-9. [Medline].

  22. Okamoto H, Mizuno K, Ohtoshi E. Cutaneous sarcoidosis with cardiac involvement. Eur J Dermatol. 1999 Sep. 9(6):466-9. [Medline].

  23. Adams MJ, Lipsitz SR, Colan SD, et al. Cardiovascular status in long-term survivors of Hodgkin's disease treated with chest radiotherapy. J Clin Oncol. 2004 Aug 1. 22(15):3139-48. [Medline].

  24. Apter S, Shemesh J, Raanani P, et al. Cardiovascular calcifications after radiation therapy for Hodgkin lymphoma: computed tomography detection and clinical correlation. Coron Artery Dis. 2006 Mar. 17(2):145-51. [Medline].

  25. Cohen SI, Bharati S, Glass J, Lev M. Radiotherapy as a cause of complete atrioventricular block in Hodgkin's disease. An electrophysiological-pathological correlation. Arch Intern Med. 1981 Apr. 141(5):676-9. [Medline].

  26. Kaplan BM, Miller AJ, Bharati S, Lev M, Martin Grais I. Complete AV block following mediastinal radiation therapy: electrocardiographic and pathologic correlation and review of the world literature. J Interv Card Electrophysiol. 1997 Nov. 1(3):175-88. [Medline].

  27. Leszczynska K, Chojnicki M, Haponiuk I, et al. [Analysis of pregnancy, labor and neonatal course in babies with prenatally-diagnosed complete atrioventricular heart block] [Polish]. Ginekol Pol. 2015 May. 86 (5):366-71. [Medline].

  28. Villain E. Pediatric cardiac pacing: indications, implant techniques, pacing mode. Ann Cardiol Angeiol (Paris). 2005 Jan. 54(1):2-6. [Medline].

  29. Saleh F, Greene EA, Mathison D. Evaluation and management of atrioventricular block in children. Curr Opin Pediatr. 2014 Jun. 26 (3):279-85. [Medline].

  30. Epstein AE, DiMarco JP, Ellenbogen KA, et al, for the American College of Cardiology Foundation, American Heart Association Task Force on Practice Guidelines, et al. 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. Circulation. 2013 Jan 22. 127 (3):e283-352. [Medline].

  31. Epstein AE, DiMarco JP, Ellenbogen KA, et al, for the American College of Cardiology Foundation, American Heart Association Task Force on Practice Guidelines, et al. 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. 2013 Jan 22. 61 (3):e6-75. [Medline].

  32. Tracy CM, Epstein AE, Darbar D, et al. 2012 ACCF/AHA/HRS focused update of the 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. J Am Coll Cardiol. 2012 Oct 2. 60 (14):1297-313. [Medline].

  33. Tracy CM, Epstein AE, Darbar D, et al. 2012 ACCF/AHA/HRS Focused Update of the 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. Heart Rhythm. 2012 Oct. 9 (10):1737-53. [Medline].

  34. Villain E, Ouarda F, Beyler C, et al. Predictive factors for late complete atrio-ventricular block after surgical treatment for congenital cardiopathy. Arch Mal Coeur Vaiss. 2003 May. 96(5):495-8. [Medline].

  35. Bullock A, Finley J, Sharratt G, Ross D. Single lead VDD pacing in children with complete heart block. Can J Cardiol. 1998 Jan. 14(1):58-62. [Medline].

  36. Bostan OM, Celiker A, Karagoz T, Ozer S, Ozme S. Dual chamber cardiac pacing in children: Single chamber pacing dual chamber sensing cardiac pacemaker or dual chamber pacing and sensing cardiac pacemaker?. Pediatr Int. 2002 Dec. 44(6):635-40. [Medline].

  37. Vatasescu R, Shalganov T, Paprika D, et al. Evolution of left ventricular function in paediatric patients with permanent right ventricular pacing for isolated congenital heart block: a medium term follow-up. Europace. 2007 Apr. 9(4):228-32. [Medline].

  38. Thambo JB, Bordachar P, Garrigue S, et al. Detrimental ventricular remodeling in patients with congenital complete heart block and chronic right ventricular apical pacing. Circulation. 2004 Dec 21. 110(25):3766-72. [Medline].

  39. Lewicka-Nowak E, Dabrowska-Kugacka A, Tybura S, et al. Right ventricular apex versus right ventricular outflow tract pacing: prospective, randomised, long-term clinical and echocardiographic evaluation. Kardiol Pol. 2006 Oct. 64(10):1082-91; discussion 1092-3. [Medline].

  40. Occhetta E, Bortnik M, Magnani A, et al. Prevention of ventricular desynchronization by permanent para-Hisian pacing after atrioventricular node ablation in chronic atrial fibrillation: a crossover, blinded, randomized study versus apical right ventricular pacing. J Am Coll Cardiol. 2006 May 16. 47(10):1938-45. [Medline].

  41. Occhetta E, Bortnik M, Magnani A, et al. Prevention of ventricular desynchronization by permanent para-Hisian pacing after atrioventricular node ablation in chronic atrial fibrillation: a crossover, blinded, randomized study versus apical right ventricular pacing. J Am Coll Cardiol. 2006 May 16. 47(10):1938-45. [Medline].

  42. Vinter S, Isaksen C, Vesterby A. Sudden cardiac death in a young woman: tumor of the atrioventricular (AV) node or citalopram intoxication?. Am J Forensic Med Pathol. 2005 Dec. 26(4):349-51. [Medline].

 
Previous
Next
 
This is an example of a normal finding on intracardiac electrophysiologic (EP) study. The surface electrocardiogram (ECG) is represented in different colors, with its corresponding intervals (ie, PR, QT) on top. A catheter with several electrodes is placed inside the heart, close to the superior vena cava–right atrial junction. This catheter records the sinoatrial node (SN) activity and is depicted here as the high-right atrial (HRA) deflection. Beneath the HRA intracardiac electrogram is the His-bundle intracardiac electrogram, which is recorded by the electrodes of a second catheter placed across the posterior aspect of the tricuspid valve. The His-bundle electrogram provides the most information about atrioventricular (AV) conduction. Three main deflections are present, with 2 intervals: (1) the A deflection corresponds to the activation of the low-right atrium, (2) the H deflection corresponds to the activation of the His-bundle before its branching into the Purkinje system, and (3) the V deflection corresponds to the activation of the proximal portion of the right ventricle. The atrium-His (A-H) interval represents the conduction time through the AV node. It shows the time elapsed between the activation of the low-right atrium (A) and the activation of the His-bundle (H), ranging normally from 50-120 milliseconds. The His-ventricle (H-V) interval is measured from the beginning of the H deflection to the beginning of the V deflection and represents the conduction time through the His-Purkinje system (normally 35-55 ms). Disease in the AV node prolongs the A-H interval, whereas disease in the distal conducting system prolongs the H-V interval.
This is a Mobitz type II second-degree atrioventricular (AV) block. The surface electrocardiograph (ECG) shows normal PR intervals and a P wave that is not followed by a QRS (in this graphic, the first P wave does not conduct through the AV node). The intracardiac electrogram shows no His deflection (H) after the blocked A deflection. In this case, the escape rhythm originates higher in the AV node at a rate of 40-50 beats per minute and is fairly reliable. However, patients may report symptoms of bradycardia such as dizziness, fatigue, and syncope. Because this type of AV block may progress to complete or third-degree AV block, patients should be monitored regularly even in the absence of symptoms.
This is a Mobitz type II second-degree atrioventricular (AV) block that may likely progress to a third-degree, or complete, AV block. The difference from the previous image is that, in this case, a His (H) deflection is present after the A deflection (the atrium-His [A-H] interval is maintained); however, no ventricle (V) deflection is present after the first H deflection. Therefore, in this case, the escape rhythm is slower than in the intracardiac electrophysiologic study of the patient in the previous image (< 40/min) and less reliable. This patient is more likely to receive a pacemaker because of the higher incidence of sudden death secondary to prolonged asystole.
This is a 12-lead electrocardiograph (ECG) of a 2-year-old girl with first-degree atrioventricular (AV) block that progressed to a complete, or third-degree, AV block (which is shown here). Her mother brought her to the clinic with described symptoms of easy tiredness and refusal to walk more than 1 block, which was a dramatic change for this girl. A normal sinus rhythm is present (shown by upward P waves in leads I, II, and aVF) at a rate of 135 per minute, which is completely dissociated from the QRS at a rate of 67 per minute. The QRS is narrow at 100 milliseconds with a frontal axis of 62°. No ventricular hypertrophy is present by voltage criteria. Because of the narrow QRS and its escape rate, this ECG is interpreted as complete AV block with junctional escape rhythm.
This is a 12-lead electrocardiograph (ECG) of a 2-year-old girl with first-degree atrioventricular (AV) block that progressed to a complete, or third-degree, AV block (see the previous image). This ECG was taken after dual chamber (DDD-R) pacemaker placement. Sinus P waves are present at a rate of 90 per minute, followed by a pacemaker spike that produces a wide QRS of 128 milliseconds. No spike occurs before each P wave, because this type of pacemaker senses the patient's own P waves and stimulates the ventricle afterward. Therefore, the patient's ventricular rate follows her physiologic needs by tracking the patient's own atrial rate. With a DDD-R pacemaker, if the patient develops sinus bradycardia, the pacemaker takes over and paces the right atrium at the programmed rate, which is followed by the ventricular stimulation, maintaining AV synchrony.
 
 
 
All material on this website is protected by copyright, Copyright © 1994-2016 by WebMD LLC. This website also contains material copyrighted by 3rd parties.