EuropeanJournal of
Europ. J. Pediat. 125, 219--224 (1977)
Pediatrics 9 by Springer-Verlag 1977
Congenital Sinus Bradycardia Combined with Congenital Total Atrioventricular Block H. Stopfkuchen and B.-K. Jfingst Universitgts-Kinderklinik, Langenbeckstr. 1, D-6500 Mainz, Federal Republic of Germany
Abstract. Sinus bradycardia and total atrioventricular block were found at the age of seven months in a boy who is now 161/2years old. According to Yaters (1929) criteria, these are likely to be congenital disorders. While the frequency of the ventricular impulse generator in the upper bundle of His only slowed in accordance with age during the period of observation, the sinus node activity deteriorated considerably. Finally potentials could only be sporadically demonstrated. Under heavy stress and with a simultaneous slight increase in ventricular frequency, a re-occurence of regular but slow sinus node activity came about. The cause of this binodal disorder of rhythm is unknown. There is no indication of family affliction or of myocarditis in early childhood. Congenital heart disease could also be excluded.
Key words: Congenital Sinus bradycardia - Sick-Sinus-Syndrome - Total atrioventricular block - Bundle of His EG.
The clinical importance of disorders of sino-atrial node function has attracted increasing attention over the past few years. In 1968 Ferrer coined the term "SickSinus-Syndrome" (SSS). This encompasses the various manifestations of gradual failure of sino-atrial node activity. Most frequently these are the bradycardia-tachycardia syndrome and the occurence of persistent sinus bradycardia. Previously, the SSS was observed mainly in people of advanced years (Bleifeld, W., et al., 1974; Rubenstein, J. J., et al., 1972). Ischaemic impairment of the sino-atrial node, as a result of sclerotic vascular changes, is the most important cause (Kaplan, B., et al., 1973; Easley, R. M., and Goldstein, S., 1971). Of considerable importance is the finding that a very high percentage of patients with the SSS show additional conduction disturbances (Bleifeld, W., et al., 1974; Narula, O., 1971; Rubenstein, J. J., et al., 1972). Recently Scott, Macartney and Deverall (1976) described six otherwise healthy boys aged between 10 and 15 years with ECG changes and clinical
220
H. Stopfkuchen and B.-K. Jtingst
s y m p t o m s typical of the SSS, i.e. sinus b r a d y c a r d i a , sinus arrest, s u p r a v e n t r i c u l a r tachycardia, vertigo a n d syncope. Sinus b r a d y c a r d i a also occurs in isolated cases in families. Here it can either be a c o n g e n i t a l disorder of the sino-atrial n o d e f u n c t i o n or one which only becomes manifest at a m o r e a d v a n c e d age (Bacos, E a g a n a n d Orgain, 1960; K h o r s a n d i a n , M o g h a d a m a n d Mtiller, 1964; Sarachek a n d L e o n a r d , 1972; Spellberg, 1971; W a g n e r a n d Hall, 1967). Often there are a d d i t i o n a l c o n d u c t i o n disorders a m o n g o t h e r m e m b e r s of the family, or indeed in the same person. The a d d i t i o n a l occurence of total a t r i o v e n t r i c u l a r block was described by Segall (1961) in adulthood. We report a 161/2 year old boy with the as yet u n d e s c r i b e d clinical picture of c o n g e n i t a l sinus b r a d y c a r d i a a n d c o n g e n i t a l total a t r i o v e n t r i c u l a r block.
Case Description Our patient, W.P., is the only child of healthy parents. No other heart disorders or sudden unexplained deaths are known in the family. The boy, who is now 1692years old, was born in November 1959 after an uneventful pregnancy. A report of the examination made immediately after birth is not available. After initially uneventful development, he was first admitted to the University Children's Clinic Mainz at the age of seven months with pronounced tachypnoea. The ECG (Table 1) at this time showed total atrioventricular block with a ventricular frequency of 57/min and a sinus bradycardia with a frequency of 59/min. At that time there was no indication of myocarditis. In the following years, while he was under continuous medical supervision, his physical development and exercise capacity were appropriate for his age. At the age of seven he had a syncopal attack which was not clearly diagnosed. Three years later he complained more frequently of headaches and rapid tiredness. Radiographs showed progressive right and left ventricular enlargement. A second degree systolic murmur at the third left interspace was presumed to be due to pulmonary stenosis. In order to take a bundle of His EG, cardiac catheterization was carried out at the age of 13years. This showed normal pressures and oxygen values.
Table 1 Date
Atrial frequency per rain
Ventricular frequency per min
QRS duration in msec
4th May 1960 3rd Nov. 1960
59 88
57 78
70 70
24th Dec. 1973 not before load determinable 24th Oct. i973 87 under load of 75 Joule • sec-1
42
--
56
--
12th Aug. 1974
40
90
not determinable
Congenital Sinus Bradycardia and Total AV-Block
221
Fig. 1. E C G of 3rd November 1960; precordial leads VI-V6; paper speed = 50 mm/sec, Total a-v block with a ventricular frequency of 78/rain and sinusbradycardia with a frequency of 88/rain
Fig. 2. Bundle of His EG of 22nd October 1973; lead II, III, V~ and bundle of His EG. HQ period 40 msec. No connection between H potentials and atrial depolarisations
222
H. Stopfkuchen and B.-K. J/Jngst
Electrocardiographic Findings The E C G t a k e n o n 4th M a y 1960, at the age o f 6 m o n t h s , s h o w e d t o t a l atriov e n t r i c u l a r b l o c k with a v e n t r i c u l a r f r e q u e n c y o f 5 7 / m i n a n d a sinus b r a d y c a r d i a o f 5 9 / r a i n ( T a b l e 1). T h e Q R S c o m p l e x e s were n o t b r o a d e n e d . T h e E C G o f 3rd N o v e m b e r 1960, at the age o f 12 m o n t h s (Table 1; Fig. 1), c o n f i r m e d the findings o f 4th M a y 1960 b u t with a n atrial f r e q u e n c y o f 8 8 / m i n a n d a v e n t r i c u t a r f r e q u e n c y o f 7 8 / m i n . P waves a n d Q R S complexes again
Fig. 3. ECG of 24th October 1973; lead VI; paper speed = 50 mm/sec. Above (before load): Total a-v block with a regular ventricular frequency of 42/rain and sporadic P waves. Below (during a load of 75 Joule/sec): Total a-v block with a ventricular frequency of 56/rain and a sinus rhythm with a frequency of 87/rain
Fig. 4. ECG of 12th August 1974; precordial leads VI-V3; paper speed = 50 mm/sec. Total a-v block with a regular ventricular frequency of 40/min and sporadic P waves
Congenital Sinus Bradycardia and Total AV-Block
223
occured completely independently of one another. Retrograde atrial stimulation did not occur. Ventricular capture was never demonstrable and atrial-ventricular dissociation determined by frequency can thus be excluded. In the bundle of His E G of 22nd October 1973 (Fig. 2) there was a normal HQ period of 40msec. The H potentials had no connection with the atrial depolarisations. In an E C G after resting on 24th October 1973 (Table and Fig. 3) the regular ventricular frequency was 42/rain. P waves appeared only sporadically and irregularly. After a load of 75 Joule/sec for four minutes, an acceleration of the ventricular frequency to 56/min took place. In the course of this load a sinus rhythm with a frequency of 87/rain occured completely independent of the ventricular rhythm. In an E C G on 12th August 1974 (Table 1; Fig. 4), the ventricular frequency was 40/min. The QRS complex continued to be normal. P waves were only sporadically demonstrable in the precordial leads. An increase in ventricular or atrial frequency could not be obtained by intravenous administration of atropine (0.01 mg/kg).
Discussion
At seven months, our patient already had a total atrioventricular block and a sinus bradycardia. According to Yater's criteria (1929) these were very probably congenital disorders. In the course of the 16 year period of observation, there was a fall in the frequency of the ventricular impulse generator in accordance with age. This stability of the ventricular pace-maker can be traced to its localisation in the atrioventricular nodal area or in the upper bundle of His, as shown by a bundle of His EG. In the same period the atrial frequency, which had already been bradycardic in early infancy, decreased still further. Finally P waves were only sporadically demonstrated. Thus, sinus node function continued to deteriorate. However, it was noticeable that with a load which increased the ventricular frequency by about 50%, regular atrial potentials again occured, although not above a frequency of 87/min. These rapidly disappeared in the recovery phase. The cause of this binodal disturbance in rhythm is unknown. Nugent et al. (1974) and Radford and Izukawa (1975) observed the SSS among children with congenital heart disease. However, in our patient congenital heart disease can be excluded, as can a myocarditis in early infancy (Radford and Izukawa, 1975). Further, in retrospect there were no indications of an increased occurence of disturbances of heart rhythm in the family. Histological examinations in cases with familial congenital sinus bradycardia, with and without additional conduction defects, have led to the demonstration of developmental disorders of varying localisation and extent in the conduction system (Green et al., 1969; Khorsandian, Moghadam and Mtiller, 1964; Lev, 1972; Sarachek and Leonard, 1972). The improvement of sinus node function under stress is against the presumption of an analogous developmental disorder in our patient. The absence of an increase in atrial frequency after administration of atropine is against the theory that the disorder is mainly due to parasympathetic activity.
224
H. Stopfkuchen and B.-K. Jtingst
References Bacos, J. M., Eagan, J. T., Orgain, E. S.: Congenital Familial Nodal Rhythm. Circulation 22,887 (1960) Bleifeld, W., Rupp, M., Fleischmann, D., Effert, S.: Syndrom des kranken Sinusknotens (SickSinus-Syndrom). Dtsch. med. Wschr. 16, 795 (1974) Easley, R. M., Goldstein, S.:~Sino-Atrial Syncope. Amer. J. Med. 50, 166 (1971) Ferret, M. I.: The Sick Sinus Syndrome in Atrial Disease. JAMA 206, 645 (1968) Green, J. R., Korovetz, M. J., Shanklin, D. R., De Vito, J. J., Taylor, W. J.: Sudden unexpected death in three generations. Arch. Intern. Med. 124, 359 (1969) Kaplan, B. M., Langendorf, R., Lev, M., Pick, A.: Tachycardia - - Bradycardia Syndrome (SoCalled "Sick Sinus Syndrome"). Amer. J. Cardiol. 31,497 (1973) Khorsandian, R. S., Moghadam, A., Mfiller, O. F.: Familial Congenital A-V Dissociation. Amer. J. Cardiol. I4, 118 (1964) Lev, M.: Pathogenesis of Congenital Atrioventricular Block. Progr. cardiovasc. Dis. 15, 145 (1972) Narnla, O.: Atrioventricular Conduction Defects in Patients with Sinus Bradycardia. Circulation 44, 1096 (1971) Nugent, E. W., Varghese, P. J., Pieroni, D. R., Rowe, R. D.: "Sluggish" Sinus Node Syndrome as part of congenital heart disease. Amer..J. Cardiol. 33, 160 (1974) Radford, D. J., Izukawa, T.: Sick Sinus Syndrome. Symptomatic cases in children. Arch. Dis. Child. 50, 879 (1975) Rubenstein, J. J., Schulman, M. D., Yurchak, P. M., De Sanctis, R. W.: Clinical Spectrum of the Sick Sinus Syndrome. Circulation 46, 5 (I972) Sarachek, N. S., Leonard, J. J.: Familial Heart Block and Sinus Bradycardia. Amer. J. Cardiol. 29, 451 (1972) Scott, O., Macartney, F. J., Deverall, P.: Sick Sinus Syndrome in Children. Arch. Dis. Child. 51, 100 (1976) Segall, H. N.: Congenital arrhythmias and conduction abnormalities in a father and four children. Can. Med. Ass. J. 84, 1283 (1961) Spellberg, R.: Familial Sinus Node Disease. Chest 60, 246 (1971) Wagner, C. W., Hall, R. J.: Congenital Familial Atrioventricular Dissociation. Report of Three Siblings. Amer. J. Cardiol. 19, 593 (1967) Yater, W. M.: Congenital Heart Block. Amer. J. Dis. Child. 38, 112 (1929)
Received January 13, 1977
Europ. J. Pediat. 125, 219--224 (1977)
Pediatrics 9 by Springer-Verlag 1977
Congenital Sinus Bradycardia Combined with Congenital Total Atrioventricular Block H. Stopfkuchen and B.-K. Jfingst Universitgts-Kinderklinik, Langenbeckstr. 1, D-6500 Mainz, Federal Republic of Germany
Abstract. Sinus bradycardia and total atrioventricular block were found at the age of seven months in a boy who is now 161/2years old. According to Yaters (1929) criteria, these are likely to be congenital disorders. While the frequency of the ventricular impulse generator in the upper bundle of His only slowed in accordance with age during the period of observation, the sinus node activity deteriorated considerably. Finally potentials could only be sporadically demonstrated. Under heavy stress and with a simultaneous slight increase in ventricular frequency, a re-occurence of regular but slow sinus node activity came about. The cause of this binodal disorder of rhythm is unknown. There is no indication of family affliction or of myocarditis in early childhood. Congenital heart disease could also be excluded.
Key words: Congenital Sinus bradycardia - Sick-Sinus-Syndrome - Total atrioventricular block - Bundle of His EG.
The clinical importance of disorders of sino-atrial node function has attracted increasing attention over the past few years. In 1968 Ferrer coined the term "SickSinus-Syndrome" (SSS). This encompasses the various manifestations of gradual failure of sino-atrial node activity. Most frequently these are the bradycardia-tachycardia syndrome and the occurence of persistent sinus bradycardia. Previously, the SSS was observed mainly in people of advanced years (Bleifeld, W., et al., 1974; Rubenstein, J. J., et al., 1972). Ischaemic impairment of the sino-atrial node, as a result of sclerotic vascular changes, is the most important cause (Kaplan, B., et al., 1973; Easley, R. M., and Goldstein, S., 1971). Of considerable importance is the finding that a very high percentage of patients with the SSS show additional conduction disturbances (Bleifeld, W., et al., 1974; Narula, O., 1971; Rubenstein, J. J., et al., 1972). Recently Scott, Macartney and Deverall (1976) described six otherwise healthy boys aged between 10 and 15 years with ECG changes and clinical
220
H. Stopfkuchen and B.-K. Jtingst
s y m p t o m s typical of the SSS, i.e. sinus b r a d y c a r d i a , sinus arrest, s u p r a v e n t r i c u l a r tachycardia, vertigo a n d syncope. Sinus b r a d y c a r d i a also occurs in isolated cases in families. Here it can either be a c o n g e n i t a l disorder of the sino-atrial n o d e f u n c t i o n or one which only becomes manifest at a m o r e a d v a n c e d age (Bacos, E a g a n a n d Orgain, 1960; K h o r s a n d i a n , M o g h a d a m a n d Mtiller, 1964; Sarachek a n d L e o n a r d , 1972; Spellberg, 1971; W a g n e r a n d Hall, 1967). Often there are a d d i t i o n a l c o n d u c t i o n disorders a m o n g o t h e r m e m b e r s of the family, or indeed in the same person. The a d d i t i o n a l occurence of total a t r i o v e n t r i c u l a r block was described by Segall (1961) in adulthood. We report a 161/2 year old boy with the as yet u n d e s c r i b e d clinical picture of c o n g e n i t a l sinus b r a d y c a r d i a a n d c o n g e n i t a l total a t r i o v e n t r i c u l a r block.
Case Description Our patient, W.P., is the only child of healthy parents. No other heart disorders or sudden unexplained deaths are known in the family. The boy, who is now 1692years old, was born in November 1959 after an uneventful pregnancy. A report of the examination made immediately after birth is not available. After initially uneventful development, he was first admitted to the University Children's Clinic Mainz at the age of seven months with pronounced tachypnoea. The ECG (Table 1) at this time showed total atrioventricular block with a ventricular frequency of 57/min and a sinus bradycardia with a frequency of 59/min. At that time there was no indication of myocarditis. In the following years, while he was under continuous medical supervision, his physical development and exercise capacity were appropriate for his age. At the age of seven he had a syncopal attack which was not clearly diagnosed. Three years later he complained more frequently of headaches and rapid tiredness. Radiographs showed progressive right and left ventricular enlargement. A second degree systolic murmur at the third left interspace was presumed to be due to pulmonary stenosis. In order to take a bundle of His EG, cardiac catheterization was carried out at the age of 13years. This showed normal pressures and oxygen values.
Table 1 Date
Atrial frequency per rain
Ventricular frequency per min
QRS duration in msec
4th May 1960 3rd Nov. 1960
59 88
57 78
70 70
24th Dec. 1973 not before load determinable 24th Oct. i973 87 under load of 75 Joule • sec-1
42
--
56
--
12th Aug. 1974
40
90
not determinable
Congenital Sinus Bradycardia and Total AV-Block
221
Fig. 1. E C G of 3rd November 1960; precordial leads VI-V6; paper speed = 50 mm/sec, Total a-v block with a ventricular frequency of 78/rain and sinusbradycardia with a frequency of 88/rain
Fig. 2. Bundle of His EG of 22nd October 1973; lead II, III, V~ and bundle of His EG. HQ period 40 msec. No connection between H potentials and atrial depolarisations
222
H. Stopfkuchen and B.-K. J/Jngst
Electrocardiographic Findings The E C G t a k e n o n 4th M a y 1960, at the age o f 6 m o n t h s , s h o w e d t o t a l atriov e n t r i c u l a r b l o c k with a v e n t r i c u l a r f r e q u e n c y o f 5 7 / m i n a n d a sinus b r a d y c a r d i a o f 5 9 / r a i n ( T a b l e 1). T h e Q R S c o m p l e x e s were n o t b r o a d e n e d . T h e E C G o f 3rd N o v e m b e r 1960, at the age o f 12 m o n t h s (Table 1; Fig. 1), c o n f i r m e d the findings o f 4th M a y 1960 b u t with a n atrial f r e q u e n c y o f 8 8 / m i n a n d a v e n t r i c u t a r f r e q u e n c y o f 7 8 / m i n . P waves a n d Q R S complexes again
Fig. 3. ECG of 24th October 1973; lead VI; paper speed = 50 mm/sec. Above (before load): Total a-v block with a regular ventricular frequency of 42/rain and sporadic P waves. Below (during a load of 75 Joule/sec): Total a-v block with a ventricular frequency of 56/rain and a sinus rhythm with a frequency of 87/rain
Fig. 4. ECG of 12th August 1974; precordial leads VI-V3; paper speed = 50 mm/sec. Total a-v block with a regular ventricular frequency of 40/min and sporadic P waves
Congenital Sinus Bradycardia and Total AV-Block
223
occured completely independently of one another. Retrograde atrial stimulation did not occur. Ventricular capture was never demonstrable and atrial-ventricular dissociation determined by frequency can thus be excluded. In the bundle of His E G of 22nd October 1973 (Fig. 2) there was a normal HQ period of 40msec. The H potentials had no connection with the atrial depolarisations. In an E C G after resting on 24th October 1973 (Table and Fig. 3) the regular ventricular frequency was 42/rain. P waves appeared only sporadically and irregularly. After a load of 75 Joule/sec for four minutes, an acceleration of the ventricular frequency to 56/min took place. In the course of this load a sinus rhythm with a frequency of 87/rain occured completely independent of the ventricular rhythm. In an E C G on 12th August 1974 (Table 1; Fig. 4), the ventricular frequency was 40/min. The QRS complex continued to be normal. P waves were only sporadically demonstrable in the precordial leads. An increase in ventricular or atrial frequency could not be obtained by intravenous administration of atropine (0.01 mg/kg).
Discussion
At seven months, our patient already had a total atrioventricular block and a sinus bradycardia. According to Yater's criteria (1929) these were very probably congenital disorders. In the course of the 16 year period of observation, there was a fall in the frequency of the ventricular impulse generator in accordance with age. This stability of the ventricular pace-maker can be traced to its localisation in the atrioventricular nodal area or in the upper bundle of His, as shown by a bundle of His EG. In the same period the atrial frequency, which had already been bradycardic in early infancy, decreased still further. Finally P waves were only sporadically demonstrated. Thus, sinus node function continued to deteriorate. However, it was noticeable that with a load which increased the ventricular frequency by about 50%, regular atrial potentials again occured, although not above a frequency of 87/min. These rapidly disappeared in the recovery phase. The cause of this binodal disturbance in rhythm is unknown. Nugent et al. (1974) and Radford and Izukawa (1975) observed the SSS among children with congenital heart disease. However, in our patient congenital heart disease can be excluded, as can a myocarditis in early infancy (Radford and Izukawa, 1975). Further, in retrospect there were no indications of an increased occurence of disturbances of heart rhythm in the family. Histological examinations in cases with familial congenital sinus bradycardia, with and without additional conduction defects, have led to the demonstration of developmental disorders of varying localisation and extent in the conduction system (Green et al., 1969; Khorsandian, Moghadam and Mtiller, 1964; Lev, 1972; Sarachek and Leonard, 1972). The improvement of sinus node function under stress is against the presumption of an analogous developmental disorder in our patient. The absence of an increase in atrial frequency after administration of atropine is against the theory that the disorder is mainly due to parasympathetic activity.
224
H. Stopfkuchen and B.-K. Jtingst
References Bacos, J. M., Eagan, J. T., Orgain, E. S.: Congenital Familial Nodal Rhythm. Circulation 22,887 (1960) Bleifeld, W., Rupp, M., Fleischmann, D., Effert, S.: Syndrom des kranken Sinusknotens (SickSinus-Syndrom). Dtsch. med. Wschr. 16, 795 (1974) Easley, R. M., Goldstein, S.:~Sino-Atrial Syncope. Amer. J. Med. 50, 166 (1971) Ferret, M. I.: The Sick Sinus Syndrome in Atrial Disease. JAMA 206, 645 (1968) Green, J. R., Korovetz, M. J., Shanklin, D. R., De Vito, J. J., Taylor, W. J.: Sudden unexpected death in three generations. Arch. Intern. Med. 124, 359 (1969) Kaplan, B. M., Langendorf, R., Lev, M., Pick, A.: Tachycardia - - Bradycardia Syndrome (SoCalled "Sick Sinus Syndrome"). Amer. J. Cardiol. 31,497 (1973) Khorsandian, R. S., Moghadam, A., Mfiller, O. F.: Familial Congenital A-V Dissociation. Amer. J. Cardiol. I4, 118 (1964) Lev, M.: Pathogenesis of Congenital Atrioventricular Block. Progr. cardiovasc. Dis. 15, 145 (1972) Narnla, O.: Atrioventricular Conduction Defects in Patients with Sinus Bradycardia. Circulation 44, 1096 (1971) Nugent, E. W., Varghese, P. J., Pieroni, D. R., Rowe, R. D.: "Sluggish" Sinus Node Syndrome as part of congenital heart disease. Amer..J. Cardiol. 33, 160 (1974) Radford, D. J., Izukawa, T.: Sick Sinus Syndrome. Symptomatic cases in children. Arch. Dis. Child. 50, 879 (1975) Rubenstein, J. J., Schulman, M. D., Yurchak, P. M., De Sanctis, R. W.: Clinical Spectrum of the Sick Sinus Syndrome. Circulation 46, 5 (I972) Sarachek, N. S., Leonard, J. J.: Familial Heart Block and Sinus Bradycardia. Amer. J. Cardiol. 29, 451 (1972) Scott, O., Macartney, F. J., Deverall, P.: Sick Sinus Syndrome in Children. Arch. Dis. Child. 51, 100 (1976) Segall, H. N.: Congenital arrhythmias and conduction abnormalities in a father and four children. Can. Med. Ass. J. 84, 1283 (1961) Spellberg, R.: Familial Sinus Node Disease. Chest 60, 246 (1971) Wagner, C. W., Hall, R. J.: Congenital Familial Atrioventricular Dissociation. Report of Three Siblings. Amer. J. Cardiol. 19, 593 (1967) Yater, W. M.: Congenital Heart Block. Amer. J. Dis. Child. 38, 112 (1929)
Received January 13, 1977
