Hostname: page-component-586b7cd67f-l7hp2 Total loading time: 0 Render date: 2024-11-24T05:32:13.087Z Has data issue: false hasContentIssue false
  • English
  • Français

Pathophysiological mechanisms of sudden infant death syndrome

Published online by Cambridge University Press:  19 August 2008

Marco Stramba-Badiale ,
Fabio Grancini ,
Norberto Porta  and
Peter J Schwartz
Marco Stramba-Badiale
Affiliation:
Istituto di Clinica Medica II, Universita’ degli Studi di Milano
Fabio Grancini
Affiliation:
Dipartimento di Medicina, Universita’ degli Studi di Pavia, Pavia
Norberto Porta
Affiliation:
Dipartimento di Medicina, Universita’ degli Studi di Pavia, Pavia
Peter J Schwartz*
Affiliation:
Dipartimento di Medicina, Universita’ degli Studi di Pavia, Pavia
*
Dr. Schwartz, Istituto di Clinica Medica II, Universita’ di Milano, Via F. Sforza 35, 20122 Milano, Italy. Tel.39-2-55 13360; Fax. 39-2-5457666.
Get access Rights & Permissions [Opens in a new window]

Abstract

There is a consensus that sudden infant death syndrome, the leading cause of mortality in the first year of life, is multifactorial. Most of the cases are probably due to respiratory or cardiac disorders. It has been proposed that some cases of sudden infant death might result from ventricular fibrillation triggered by a sudden increase in sympathetic activity affecting the heart with reduced electrical stability. This impairment can be due to an insufficient or delayed development of cardiac vagal innervation, with the resultant lack of its protective effect that has been demonstrated to be present since the third week of life. Clinical studies suggest that some of the sudden infant death victims may have a reduced heart rate variability that could be interpreted as a decreased parasympathetic activity to the heart. On the other hand, a reduced cardiac electrical stability may be provoked by a developmental imbalance in sympathetic innervation such to create a dominance of left-sided nerves. We have demonstrated that an imbalance of this type experimentally induced in puppies increases the susceptibility to ventricular fibrillation and prolongs QT interval. In order to demonstrate a significant relationship between prolonged QT interval and sudden infant death, we performed a large prospective study on 18,832 neonates. QT interval corrected for heart rate (QTc) measured from an electrocardiogram on the fourth day of life, was within the normal limits in nine victims from known causes, while it was exceeding the mean by two standard deviations (>433 msec) in six of 12 sudden infant death victims. If these data are confirmed by a larger multicenter study started in Italy, it will be possible to identify some of the sudden infant death victims by the observation of a prolonged QT interval on the electrocardiogram. In this case a preventive strategy based on a time-limited administration of beta adrenergic blocking agents to the infants at risk, might reduce the incidence of sudden infant death.

Keywords

Sudden infant death syndromearryhthmia
Type
Original Articles
Information
Cardiology in the Young , Volume 2 , Issue 3 , July 1992 , pp. 272 - 276
Copyright
Copyright © Cambridge University Press 1992

Access options

Get access to the full version of this content by using one of the access options below. (Log in options will check for institutional or personal access. Content may require purchase if you do not have access.)

References

1. Schwartz, PJ, Southall, D, Valdes Dapena, M. The Sudden Infant Death Syndrome. Cardiac and respiratory mechanisms and interventions. Ann New York Acad Sciences 1988; 533.Google Scholar
2. Schwartz, PJ. The quest for the mechanism of the sudden infant death syndrome. Doubts and progress. Circulation 1987; 75: 677–683.CrossRefGoogle ScholarPubMed
3. Schwartz, PJ. Cardiac sympathetic innervation and the sudden infant death syndrome. A possible pathogenetic link. Am J Med 1976; 60: 167–172.Google Scholar
4. Schwartz, PJ, Stramba-Badiale, M. Parasympathetic nervous system and malignant arrhythmias. In: Neurocardiology. Kulbertus, HE and Frank, MN., eds. Futura Publishing Co., Mount Kisco, New York 1988: 179–200.Google Scholar
5. Stramba-Badiale, M, Lazzarotti, M, Schwartz, PJ. Postnatal development of cardiac innervation and susceptibility to malignant arrhythmias in the dog. J Autonomic Nervous System 1990; 30:S153–S154.CrossRefGoogle ScholarPubMed
6. Schwartz, PJ, Vanoli, E, Stramba-Badiale, M, De Ferrari, GM, Billman, , Foreman, RD. Autonomic mechanisms and sudden death. New insights from the analysis ofbaroreceptor reflexes in conscious dogs with and without a myocardial infarction. Circulation 1988; 78: 969–979.Google Scholar
7. La Rovere, MT, Specchia, G, Mortara, A, Schwartz, PJ. Baroreflex sensitivity, clinical correlates, and cardiovascular mortalityamong patients with a first myocardial infarction. Circulation 1988; 78: 816–824.Google Scholar
8. Hull, SS Jr, Evans, AR, Vanoli, E, Adamson, PB, Stramba-Badiale, M, Albert, DE, Foreman, RD, Schwartz, PJ. Heart rate variability before and after myocardial infarction in conscious dogs at high and low risk ofsudden death. J Am Coll Cardiol 1990; 16: 978–985.Google Scholar
9. Kleiger, RE, Miller, JP, Bigger, JT Jr, Moss, AJ. The Multicenter Post-Infarction Research Group: Decreased heart rate variability and its association with increased mortality after acute myocardial infarction. Am J Cardiol 1987; 59: 256–262.CrossRefGoogle Scholar
10. Schechtman, VL, Harper, RM, Kluge, KA, Wilson, AJ, Hoffman, HJ, Southall, DP. Cardiac and respiratory patterns in normal infants and victims of the sudden infant death syndrome. Sleep 1988; 11: 413–424.CrossRefGoogle ScholarPubMed
11. Kluge, KA, Harper, RM, Schechtman, VL, Wilson, AJ, Hoffman, HJ, Southall, DP. Spectral analysis assessment of respiratory sinus arrhythmia in normal infants and infants who subsequently died of sudden infant death syndrome. Pediatr Res 1988; 24: 677–682.CrossRefGoogle ScholarPubMed
12. Cauchemez, B, Peirano, P, Samson-Dolfus, D, Lucet, V, Attuel, P, Kauffmann, F, Maison-Blanche, P, Monod, N, Coumel, P. Le systeme nerveux autonome dans le syndrome de Ia mort subite du nourrisson. Analyse du rythme cardiaque et de la variabilite sinusale sur les enregistrements Holter d'enfants decedes du syndrome. Arch Mal Coeur 1989; 82: 745–752.Google Scholar
13. Schwartz, PJ. Sympathetic inbalance and cardiac arrhythmias. In: Nervous control of cardiovascular function. Randall, WC. (ed), Oxford University Press, NY, 1984: 225–251.Google Scholar
14. Stramba-Badiale, M, Lazzarotti, M, Schwartz, PJ. Postnatal development of cardiac innervation and susceptibility to malignant arrhythmias. Circulation 1989; 80 (Suppl II): II 388.Google Scholar
15. Gootman, PM, Cohen, HL, Gootman, N. Autonomic nervous system regulation of heart rate in the perinatal period. In: Pediatric and fundamental electrocardiography. Liebman, J, Plonsey, R, Rudy, Y. (eds). Martinus Nijhoff,The Hague, 1987, pp 137–159.Google Scholar
16. Grancini, F, Segantini, A, Palla, F, Porta, N, Imberti, D, Sauce, P, Austoni, P, Poggio, GL and Schwartz, PJ. Sudden infant death syndrome: neonatal ECG screening. The Third World Congress of Pediatric Cardiology, Bangkok, 1989; F362: 93.Google Scholar
17. Schwartz, PJ, Montemerlo, M, Facchini, M, Salice, P, Rosti, D, Poggio, GL, Giorgetti, R. The QT interval throughout the first six months of life: A prospective study. Circulation 1982; 66: 496.Google Scholar
18. Southall, DP, Arrowsmith, WA, Stebbens, YE, Alexander, JR. QT interval measurements before Sudden Infant Death Syndrome.Arch Dis Child 1986; 61: 237–243.CrossRefGoogle ScholarPubMed
19. Sadeh, D, Shannon, DC, Abboud, S, Saul, JP, Akselrod, S, Cohen, RJ. Altered cardiac repolarization in some victims of Sudden Infant Death Syndrome. New Engi J Med 1987; 24: 1501–1505.Google Scholar