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Prolonged QT and Torsades de Pointes in a child with late-onset post-operative complete heart block

Part of:Cardiac Morphology

Published online by Cambridge University Press:  24 March 2022

Sezen Gulumser SiskoOpen the ORCID record for Sezen Gulumser Sisko[Opens in a new window],
Bahar Caran,
Hasan C. KafaliOpen the ORCID record for Hasan C. Kafali[Opens in a new window] and
Yakup Ergul
Sezen Gulumser Sisko*
Affiliation:
Department of Pediatric Cardiology, University of Health Sciences, Istanbul Mehmet Akif Ersoy Thoracic and Cardiovascular Surgery Training and Research Hospital, Istanbul, Turkey
Bahar Caran
Affiliation:
Department of Pediatric Cardiology, University of Health Sciences, Istanbul Mehmet Akif Ersoy Thoracic and Cardiovascular Surgery Training and Research Hospital, Istanbul, Turkey
Hasan C. Kafali
Affiliation:
Department of Pediatric Cardiology, University of Health Sciences, Istanbul Mehmet Akif Ersoy Thoracic and Cardiovascular Surgery Training and Research Hospital, Istanbul, Turkey
Yakup Ergul
Affiliation:
Department of Pediatric Cardiology, University of Health Sciences, Istanbul Mehmet Akif Ersoy Thoracic and Cardiovascular Surgery Training and Research Hospital, Istanbul, Turkey
*
Author for correspondence: S. Gulumser Sisko, Department of Pediatric Cardiology, University of Health Sciences, Istanbul Mehmet Akif Ersoy Thoracic and Cardiovascular Surgery Training and Research Hospital, Istanbul, Turkey. Tel: +90536 666 23 22; Fax: +90 (212) 471 94 94. E-mail: nezes_d@hotmail.com
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Abstract

A young child presented with syncope attacks. Late-onset post-operative complete atrioventricular block and Torsades de Pointes were diagnosed. She was treated with surgical epicardial pacemaker implantation. This report is the description of Torsades de Pointes due to late-onset post-operative complete atrioventricular block followed by R on T phenomenon in a child.

Keywords

Childrensyncopeatrioventricular blockTorsades de Pointes

Information

Type
Brief Report
Information
Cardiology in the Young , Volume 32 , Issue 11 , November 2022, pp. 1866 - 1868
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Copyright
© The Author(s), 2022. Published by Cambridge University Press

Bradycardia, complete, or advanced atrioventricular block are among the factors responsible for the occurrence of Torsades de Pointes. Reference Moroe, Saku, Tashiro, Hiroki and Arakawa1 In this case report, we present a young child with syncope attacks who had Torsades de Pointes because of late-onset postoperative complete atrioventricular block.

Case presentation

A 5-year-old girl with Down syndrome was admitted from another hospital with an episode of syncope. The patient’s vital signs were within normal limits, except for marked bradycardia. When she was 6 months old, she had been operated for a ventricular septal defect. She went to post-operative follow-ups regularly and there were no problems. She had no a family history of CHD or cardiac conduction disease. Her parents had normal electrocardiograms and normal QT intervals. She was not taking any QT prolonging medications. The patient was referred to our centre for further treatment.

Her laboratory findings were normal complete blood count, normal liver and kidney functions, and normal serum electrolyte levels. Her initial electrocardiogram showed a complete atrioventricular block at a rate of 60 beats per minutes (bpm) (Fig 1a). The echocardiogram revealed enlarged left atrium and left ventricle. Near normal left ventricular systolic function was detected with an ejection fraction of 50%.

Figure 1.

( a ) Complete atrioventricular block is seen (ventricular rate: 60 bpm) at the 12 lead electrocardiogram (red dots indicate atrial activity and blue dots indicate ventricular activity). ( b ) Holter recording of complete atrioventricular block patient. Torsades de pointes is appearing with prolonged QT interval and R on T phenomenon.

The patient was taken to the ICU, and her heart ryhythm was monitored and Holter recording was started. In the intensive care follow-up, the patient had an attack of syncope. Due to bradycardia (heart rate 30 bpm), cardiopulmonary resuscitation lasting 2 minutes was performed. While isoproteronol infusion was initiated immediately, the patient was urgently taken to the catheterisation room and a temporary pacemaker was implanted. R on T phenomenon and short-term Torsades de Pointes oscillation were observed in the Holter recordings of the patient at the time of the syncope. Also, she had a prolonged QT interval (850 ms) (Fig 1b).

An epicardial, dual-chamber pacemaker, and two leads placed in the right atrium and left ventricle apex were surgically implanted because of late-onset post-operative complete atrioventricular block (Fig 2a). She did not have attack of syncope or ventricular arrhytmia. QT interval returned to normal at 2-month follow-up (Fig 2b).

Figure 2.

( a ) Chest X-ray shows an epicardial, dual-chamber pacemaker, and two leads placed in the right atrium and left ventricle apex. ( b ) Normal QT interval after permanent pacemaker at the 12 lead electrocardiogram.

Discussion

The incidence of complete heart block after open-heart surgery is between 1 and 3%. Reference Gross, Chiu, Hamilton, Kirsh and Stephenson2 Especially patients with Down syndrome undergoing ventricular septal defect repair had a higher rate of heart block requiring permanent pacemaker implantation. Reference Fudge, Li and Jaggers3,Reference Tucker, Pyles, Bass and Moller4 Usually, heart block occurs immediately after surgery or in the early post-operative period. Rarely, it may occur months or years after surgery. Reference Bonatti, Agnetti and Squarcia5–Reference Ayyildiz, Kasar and Ozturk7 In this case, complete atrioventricular block developed 4 years after surgical ventricular septal defect repair. In the literature, patients who were in sinus rhythm after the surgical procedure and had a pacemaker inserted years later were described but the incidence of postoperative late-onset atrioventricular block has not been clearly determined. Reference Lin, Mahle and Frias8,Reference Liberman, Pass, Hordof and Spotnitz9

It is possible to manage in a timely manner by closely monitoring if the heart block develops in the early post-operative period. However, patients who develop heart block in the late post-operative period may be asymptomatic or present with non-specific findings such as fatigue. At worse, they may present with heart failure, syncope, and sudden death. For this reason, telemetry control is very important in the post-operative follow-ups of patients who have had congenital heart surgery, even if they are discharged from hospital in sinus rhythm.

It is possible to predict that some patients may develop heart block. Postoperatively transient complete atrioventricular block, long PR according to pre-operative telemetry, and different P and QRS morphology are among the stimulating factors. Reference Lin, Mahle and Frias8,Reference Villain, Ouarda, Beyler, Sidi and Abid10 The possible post-operative risk factors are unknown in our patient. Down Syndrome and perimembranous ventricular septal defect were predictable risks for the patient in the preoperative period. There are similar cases in the literature. Reference Nasser, Mesned, Mohamad and Kabbani11,Reference Altaweel, Kabbani, Hijazi, Hammadah and Al Ghamdi12

Our case is also an excellent example of Torsades de pointes-related syncope in complete atrioventricular block. Bradyarrhythmia is an expected finding in patients with complete atrioventricular block. However, it is rare for bradyarrhythmias to be associated with QT interval prolongation and Torsades de pointes. Reference Subbiah, Gollob and Gula13 Kurita et al. Reference Kurita, Ohe and Marui14 hypothesises that patients with complete atrioventricular block have a bradycardia-sensitive repolarisation abnormality, and therefore may develop Torsades de pointes. In our case, the heart rate was under 60 bpm and Torsades de pointes started by an ectopic ventricular complex interrupting the T wave before isoproteronol infusion.

Conclusions

The definitive treatment of late-onset post-operative atrioventricular block is permanent pacemaker implantation. It should be kept in mind that the conduction system should be carefully monitored in the long-term follow-up of patients who have had congenital heart surgery.

Acknowledgement

We thank our paediatric cardiac surgery team for their valuable support.

Financial support

The clinicians received no grants from any funding agency and no support from any commercial or not-for-profit sector.

Conflicts of interest

None.

Ethical standards

The authors assert that this work complies with the ethical standards of the relevant national guidelines on human experimentation and with the Helsinki Declaration of 1975, as revised in 2008. This case was approved by the patient’s family.

References

Moroe, K, Saku, K, Tashiro, N, Hiroki, T, Arakawa, K. “Torsades de pointes" and atrioventricular block. Clin Cardiol 1988; 11: 9–13. DOI 10.1002/clc.4960110111.CrossRefGoogle ScholarPubMed
Gross, GJ, Chiu, CC, Hamilton, RM, Kirsh, JA, Stephenson, EA. Natural history of postoperative heart block in congenital heart disease: implications for pacing intervention. Heart Rhythm 2006; 3: 601–604. DOI 10.1016/j.hrthm.2006.01.023.CrossRefGoogle ScholarPubMed
Fudge, JC Jr, Li, S, Jaggers, J, et al. Congenital heart surgery outcomes in down syndrome: analysis of a national clinical database. Pediatrics 2010; 126: 315–322. DOI 10.1542/peds.2009-3245.CrossRefGoogle ScholarPubMed
Tucker, EM, Pyles, LA, Bass, JL, Moller, JH. Permanent pacemaker for atrioventricular conduction block after operative repair of perimembranous ventricular septal defect. J Am Coll Cardiol 2007; 50: 1196–1200. DOI 10.1016/j.jacc.2007.06.014.CrossRefGoogle ScholarPubMed
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; 20: 181–186.Google ScholarPubMed
Andersen, HØ., de Leval, MR, Tsang, VT, Elliott, MJ, Anderson, RH, Cook, AC. Is complete heart block after surgical closure of ventricular septum defects still an issue? Ann Thorac Surg 2006; 82: 948–956. DOI 10.1016/j.athoracsur.2006.04.030.CrossRefGoogle ScholarPubMed
Ayyildiz, P, Kasar, T, Ozturk, E, et al. Evaluation of permanent or transient complete heart block after open heart surgery for congenital heart disease. Pacing Clin Electrophysiol 2016; 39: 160–165. DOI 10.1111/pace.12778.CrossRefGoogle ScholarPubMed
Lin, A, Mahle, WT, Frias, PA, et al. Early and delayed atrioventricular conduction block after routine surgery for congenital heart disease. J Thorac Cardiovasc Surg 2010; 140: 158–160. DOI 10.1016/j.jtcvs.2009.12.050.CrossRefGoogle ScholarPubMed
Liberman, L, Pass, RH, Hordof, AJ, Spotnitz, HM. Late onset of heart block after open heart surgery for congenital heart disease. Pediatr Cardiol 2008; 29: 56–59. DOI 10.1007/s00246-007-9034-x.CrossRefGoogle ScholarPubMed
Villain, E, Ouarda, F, Beyler, C, Sidi, D, Abid, F. Facteurs prédictifs de bloc auriculo-ventriculaire complet tardif après traitement chirurgical des cardiopathies congénitales [Predictive factors for late complete atrio-ventricular block after surgical treatment for congenital cardiopathy]. Arch Mal Coeur Vaiss 2003; 96: 495–498.Google Scholar
Nasser, BA, Mesned, AR, Mohamad, T, Kabbani, MS. Late-presenting complete heart block after pediatric cardiac surgery. J Saudi Heart Assoc 2016; 28: 59–62. DOI 10.1016/j.jsha.2015.06.004.CrossRefGoogle ScholarPubMed
Altaweel, H, Kabbani, MS, Hijazi, O, Hammadah, HM, Al Ghamdi, S. Late presenting complete heart block after surgical repair of ventricular septal defect. Egypt Heart J 2018; 70: 455–459. DOI 10.1016/j.ehj.2018.10.006.CrossRefGoogle ScholarPubMed
Subbiah, RN, Gollob, MH, Gula, LJ, et al. Torsades de pointes during complete atrioventricular block: genetic factors and electrocardiogram correlates. Can J Cardiol 2010; 26: 208–212. DOI 10.1016/s0828-282x(10)70369-x.CrossRefGoogle ScholarPubMed
Kurita, T, Ohe, T, Marui, N, et al. Bradycardia-induced abnormal QT prolongation in patients with complete atrioventricular block with torsades de pointes. Am J Cardiol 1992; 69: 628–633. DOI 10.1016/0002-9149(92)90154-q.CrossRefGoogle ScholarPubMed
Figure 0

Figure 1.(a) Complete atrioventricular block is seen (ventricular rate: 60 bpm) at the 12 lead electrocardiogram (red dots indicate atrial activity and blue dots indicate ventricular activity). (b) Holter recording of complete atrioventricular block patient. Torsades de pointes is appearing with prolonged QT interval and R on T phenomenon.

Figure 1

Figure 2.(a) Chest X-ray shows an epicardial, dual-chamber pacemaker, and two leads placed in the right atrium and left ventricle apex. (b) Normal QT interval after permanent pacemaker at the 12 lead electrocardiogram.