HEART Two patients are described who presented with seizures. Electrocardiogram revealed complete heart block with ventricular asystole lasting four to 10 seconds in each case. These Stokes-Adams episodes were controlled with temporary transvenous pacing. Although there was full clinical recovery in each case, both patients continue to have right bundle branch block (RBBB) and left anterior hemiblock (LAH) 1½ years after their initial presentation.
ACQUIRED mainly
G UIREI3 complete
heart block is limited to adults, though sporadic reports of acquired complete heart block in children can be found. 1-3 Conduction abnormalities may be caused by inflammatory diseaseS4 or tumors of the heart involving the conduction systeM.5 Most of the recent reports regarding children with acquired complete heart block .refer to acute bacterial
infections, especially
Complete Heart Block
Mimicking
meningococcemia. 1-2
Disorder
Recently, a 20-year-old male with Coxsackie B myocarditis and complete heart block was successfully treated with temporary pacing This is a report of two children with probable viral myocarditis and complete heart block with Stokes-Adams episodes, episodes which
were
venous
controlled with temporary
Seizure
trans-
Observations
pacing.
on
Two Cases
Case Reports Case 1. A 14-year-old black male had been in the best of health until four days prior to admission when he started having a low-grade fever associated with vague mild abdominal pain and occasional vomiting. He was treated with aspirin but on the day of admission to Children’s Hospital of Michigan, he had experienced five episodes of generalized stiffening of the body and tonic-clonic seizures of the upper extremities lasting a few seconds, followed by spontaneous full recovery. The birth history and past history were unremarkable. On examination, he was a healthy looking, well-nourished child who was fully conscious and alert except during syncopal episodes. The bload ~ pressure was 100/80; pulse rate 75 per minute, and respiration rate 20 per minute. The heart
Zai Q.
Farooki, M.D.,
James G.
Henry, M.D.,
Edward W. Green, M.D.
&dquo;
Department
of
Pediatrics, Section of Cardiology, of Michigan and Wayne State University, School of Medicine, Detroit, Mich. Children’s
Hospital
345
Downloaded from cpj.sagepub.com at NANYANG TECH UNIV LIBRARY on May 24, 2015
FIG. I (Case I)., Panel A.: Monitor lead I at 25 mm/sec shows an atrial rate of 15/per minute. However, the initial 9 atrial impulses fail to show anterograde conduction, indicating complete heart block. The latter part of the strip shows spontaneous improvement of atrioventricular conductivity to 2:1. The ventricular complex shows a deep S wave suggestive of left anterior hemlblock. Panel B: ECG recorded at 50 mm/sec shows the initial forces to be directed to the right and inferiorly and the main forces are directed to the left and superiorly. AVL shows a prominent Q wave with a tall R wave and an intrinsicoid deflection of 0.03 seconds. A small q wave in V2 to US is probably due to initial posteroinferior left ventricular wall activation. The Q wave in V6 is very small. These findings are suggestive of left anterior hemiblock, The associated complete right bundle branch block results in wide slurred terminal S wave in V6 and terminal R wave in AVR.
sounds were normal. The pulses were symmetrical. The liver was palpable 2 cm below the right costal margin. The abdomen was soft. During the examination, the patient’s heart rate declined to 30 per minute. This was followed by a staring look, stiffening of lower extremities and tonic rigidity of the arms lasting about four seconds. Full recovery was spontaneous. During the syncopal episodes, ventricular asystole lasted a few seconds with spontaneous recovery to 2:1l atrioventricular block (Fig. l-; A). The electrocardiogram revealed an intermittent sinus rhythm of 75/minute, QRS duration of 0.15 seconds, maximum PR interval of 0.13 seconds, QT interval of 0.40 seconds, mean frontal axis at -5fl°, Ql’ S3 pattern, and complete right bundle branch block (Fig. 1, B). The chest x-ray revealed a cardiothoracic ratio of 0.5, prominent left atrium, and a small left pleural effusion. Repetitive episodes of ventricular asystole necessitated immediate insertion of a temporary transvenous °
pacemaker catheter into the right ventricular apex. Pacing with a demand Medtronic unit resulted in complete cessation of his symptoms. A wide variety of laboratory tests led to normal results. A culture from the throat grew Stcaphyloeoccus aureic.r, coagulase positive. The patient was treated with oral penicillin. The fever abated by the fourth hospital day. The heart size seemed smaller on the 10th day. On the 14th hospital day, the pacemaker was turned off and the patient maintained a sinus rhythm of 75 per minute without evidence of AV block. He continued to have an ECG pattern of right bundle branch block (RBBB) and left anterior hemiblock (LAH). The pacemaker catheter was removed on the 16th hospital day. The patient remains completely asymptomatic 20 months after the onset of his syncopal episodes. to
Case 2. An I I -year-old Children’s Hospital of
346
Downloaded from cpj.sagepub.com at NANYANG TECH UNIV LIBRARY on May 24, 2015
black girl
Michigan
was
in
admitted of
a state
(Case 2). Panel A: Monitor lead II at 25 mm/sec shows an atrial rate of 140/mt. There is complete failure of anterograde conduction. Panel B: ECG recorded at 50 mm/sec shows the initial QRS forces directed inferiorly and to the right, while the main forces are left and superior. Vs and V6 show minimal Q wave. These findings are suggestive of LAH. There is additional RBBB. The pacemaker artifact is not seen. There was a sinus rhythm of 75/mt. Panel C: Reveals remarkable change in the activation pattern of the ventricles. The initial QRS forces are directed superiorly and leftwards, while the main forces are inferior and to the right. There is associated RBBB. V5 and V6 show paced beats. V.~ shows a QS pattern. This ECG is compatible with the diagnosis of left posterior hemiblock and RBBB. FIG. 2
cardiovascular collapse. She had been in apparent good health until three days prior to admission when she started complaining of headaches. The day prior to admission, she was noted to be having generalized tonic seizures during sleep, lasting only a few minutes. The patient had three subsequent seizures. On arrival at the hospital, she was nonresponsive, the blood pressure was unrecordable, the pulses were nonpalpable, and there were occasional faint heart sounds. The electrocardiogram revealed complete heart block with occasional ventricular beats (Fig. 2, A). Isoproterenol infusion resulted in immediate increase of heart rate to 80 per minute and clinical improvement was marked. A temporary transvenous pacemaker catheter was immediately positioned in the right ventricular apex. A few minutes after effective pacing with a demand Medtronic unit was established, the
patient was fully conscious and alert. No precordial murmur was heard. Physical examination was normal. The chest x-ray revealed a normal heart size and venous congestion had not occurred. The electrocardiogram on admission revealed complete heart block, atrial rate 145/mt; variable ventricular rate between 20 to 50/mt and wide QRS complexes of varying shapes in the same lead suggestive of a changing low ventricular focus. Figure 2 demonstrates three different patterns of conduction defects. Panel B shows a pattern of LAH with RBBB and panel C is suggestive of left posterior hemiblock with RBBB. Most laboratory tests gave normal results. A throat culture was positive for beta hemolytic streptococci. The initial ASO titer of 166 increased to 373 at two weeks after admission; sedimentation rate 10; CPK 27; SGOT declined from initial level of 440 to 154 to 30; LDH
347
Downloaded from cpj.sagepub.com at NANYANG TECH UNIV LIBRARY on May 24, 2015
declined from initial level of 1,500 to 1,440 to 1,200 to 660; isoenzyme LDH for heart was increased. The complement fixation titers for herpes, influenza A & B, and mycoplasma were
negative. The hospital course was uneventful. Serial electrocardiograms revealed a pattern of RBBB and LAH. Upon removal of the pacing catheter the 9th day, she maintained a stable sinus and was discharged. She continues to remain asymptomatic 18 months after the onset of her initial symptoms despite persistence of RBBB with LAH. on
rhythm
Discussion
,
The patient in Case 1 had Stokes-Adams attacks following a brief illness probably viral in origin. His throat culture grew Staphylococcus aureus. However, his blood cultures remained negative and the course of his illness was not characteristic of staphylococcal septicemia or endocarditis with heart block. The electrocardiograms revealed a pattern of complete atrioventricular block which was intermittent and resulted in syncope and seizures. Spontaneous improvement to 2:1I A.V. block and then to sinus rhythm was consistently seen. The electrocardiographic pattern during atrioventricular conduction was compatible with LAH with RBBB. We were unable to record a pattern of left posterior hemiblock. However, it is assumed that intermittent interference with conduction through the left posterior fascicle resulted in complete heart block, i.e., trifascicular block. The course of his illness is suggestive of complete recovery of left posterior fascicle, while the left anterior fascicle and the right bundle branch seem to have been permanently affected. The patient in Case 2 presented with cardiovascular collapse caused by very slow heart rate. She also had a brief preceding illness, probably viral in nature. The throat culture grew beta hemolytic Streptococcus and ASO titers were mildly elevated. She did not develop valvulitis or other manifestations of rheumatic fever. The electrocardiogram revealed three distinct patterns. First, intermittent complete blockage of atrioventricular
conduction resulted in very slow heart rate and seizures. Spontaneous recovery to a pattern of sinus rhythm with LAH and RBBB occurred most of the time. However, on one occasion, a pattern of left posterior hemiblock with RBBB was recorded. This phenomenon is compatible with the assumption that complete anterograde atrioventricular conduction block was secondary to the conduction defect in the three main bundles, i.e., trifascicular block. The course of this patient’s illness is also suggestive of eventual recovery of the left posterior fascicle, while the right bundle and the left anterior fascicle seem to have been permanently affected. Temporary transvenous demand pacing proved lifesaving in both patients. Although clinical recovery was full, they continue to show RBBB and LAH months after the onset of their symptoms. Both are now attending school and have had no CNS or cardiac symptoms since their discharge from the hospital. Their long-term prognosis is guarded, as they seem more vulnerable to develop complete heart block. In summary, these two cases should alert the practicing physicians to acquired complete heart block presenting as a seizure disorder. Recognition of the basic problem and rapid institution of pacemaker therapy could prove lifesaving. The diagnosis of heart block should probably be considered in any patient with atypical seizures.
References 1.
and Lee, P. L.: Complete atrioventricular heart block secondary to acute myocarditis requiring intracardiac pacing. J. Pediatr. 78:
Johnson, L. J., 312, 1971.
S. J.: Atrioventricular node inflammation—mechanism of sudden death in protracted meningococcemia. N. Engl. J. Med. 286: 1091, 1972. 3. Clinicopathologic conference—Case 20-1972. N. Engl. J. Med. 286: 1100, 1972. 4. Wenger, N. K.: Infectious myocarditis. In Cardiovascular Clinics, Burch G. E., Ed. Vol. 4, Number 1, pp. 168-185. Philadelphia, F. A. Davis Co., 1972. 5. Harvey, P.: Clinical aspects of cardiac tumors. Am. J. Cardiol. 21: 328, 1968. 2.
Robboy,
348
Downloaded from cpj.sagepub.com at NANYANG TECH UNIV LIBRARY on May 24, 2015
ACQUIRED mainly
G UIREI3 complete
heart block is limited to adults, though sporadic reports of acquired complete heart block in children can be found. 1-3 Conduction abnormalities may be caused by inflammatory diseaseS4 or tumors of the heart involving the conduction systeM.5 Most of the recent reports regarding children with acquired complete heart block .refer to acute bacterial
infections, especially
Complete Heart Block
Mimicking
meningococcemia. 1-2
Disorder
Recently, a 20-year-old male with Coxsackie B myocarditis and complete heart block was successfully treated with temporary pacing This is a report of two children with probable viral myocarditis and complete heart block with Stokes-Adams episodes, episodes which
were
venous
controlled with temporary
Seizure
trans-
Observations
pacing.
on
Two Cases
Case Reports Case 1. A 14-year-old black male had been in the best of health until four days prior to admission when he started having a low-grade fever associated with vague mild abdominal pain and occasional vomiting. He was treated with aspirin but on the day of admission to Children’s Hospital of Michigan, he had experienced five episodes of generalized stiffening of the body and tonic-clonic seizures of the upper extremities lasting a few seconds, followed by spontaneous full recovery. The birth history and past history were unremarkable. On examination, he was a healthy looking, well-nourished child who was fully conscious and alert except during syncopal episodes. The bload ~ pressure was 100/80; pulse rate 75 per minute, and respiration rate 20 per minute. The heart
Zai Q.
Farooki, M.D.,
James G.
Henry, M.D.,
Edward W. Green, M.D.
&dquo;
Department
of
Pediatrics, Section of Cardiology, of Michigan and Wayne State University, School of Medicine, Detroit, Mich. Children’s
Hospital
345
Downloaded from cpj.sagepub.com at NANYANG TECH UNIV LIBRARY on May 24, 2015
FIG. I (Case I)., Panel A.: Monitor lead I at 25 mm/sec shows an atrial rate of 15/per minute. However, the initial 9 atrial impulses fail to show anterograde conduction, indicating complete heart block. The latter part of the strip shows spontaneous improvement of atrioventricular conductivity to 2:1. The ventricular complex shows a deep S wave suggestive of left anterior hemlblock. Panel B: ECG recorded at 50 mm/sec shows the initial forces to be directed to the right and inferiorly and the main forces are directed to the left and superiorly. AVL shows a prominent Q wave with a tall R wave and an intrinsicoid deflection of 0.03 seconds. A small q wave in V2 to US is probably due to initial posteroinferior left ventricular wall activation. The Q wave in V6 is very small. These findings are suggestive of left anterior hemiblock, The associated complete right bundle branch block results in wide slurred terminal S wave in V6 and terminal R wave in AVR.
sounds were normal. The pulses were symmetrical. The liver was palpable 2 cm below the right costal margin. The abdomen was soft. During the examination, the patient’s heart rate declined to 30 per minute. This was followed by a staring look, stiffening of lower extremities and tonic rigidity of the arms lasting about four seconds. Full recovery was spontaneous. During the syncopal episodes, ventricular asystole lasted a few seconds with spontaneous recovery to 2:1l atrioventricular block (Fig. l-; A). The electrocardiogram revealed an intermittent sinus rhythm of 75/minute, QRS duration of 0.15 seconds, maximum PR interval of 0.13 seconds, QT interval of 0.40 seconds, mean frontal axis at -5fl°, Ql’ S3 pattern, and complete right bundle branch block (Fig. 1, B). The chest x-ray revealed a cardiothoracic ratio of 0.5, prominent left atrium, and a small left pleural effusion. Repetitive episodes of ventricular asystole necessitated immediate insertion of a temporary transvenous °
pacemaker catheter into the right ventricular apex. Pacing with a demand Medtronic unit resulted in complete cessation of his symptoms. A wide variety of laboratory tests led to normal results. A culture from the throat grew Stcaphyloeoccus aureic.r, coagulase positive. The patient was treated with oral penicillin. The fever abated by the fourth hospital day. The heart size seemed smaller on the 10th day. On the 14th hospital day, the pacemaker was turned off and the patient maintained a sinus rhythm of 75 per minute without evidence of AV block. He continued to have an ECG pattern of right bundle branch block (RBBB) and left anterior hemiblock (LAH). The pacemaker catheter was removed on the 16th hospital day. The patient remains completely asymptomatic 20 months after the onset of his syncopal episodes. to
Case 2. An I I -year-old Children’s Hospital of
346
Downloaded from cpj.sagepub.com at NANYANG TECH UNIV LIBRARY on May 24, 2015
black girl
Michigan
was
in
admitted of
a state
(Case 2). Panel A: Monitor lead II at 25 mm/sec shows an atrial rate of 140/mt. There is complete failure of anterograde conduction. Panel B: ECG recorded at 50 mm/sec shows the initial QRS forces directed inferiorly and to the right, while the main forces are left and superior. Vs and V6 show minimal Q wave. These findings are suggestive of LAH. There is additional RBBB. The pacemaker artifact is not seen. There was a sinus rhythm of 75/mt. Panel C: Reveals remarkable change in the activation pattern of the ventricles. The initial QRS forces are directed superiorly and leftwards, while the main forces are inferior and to the right. There is associated RBBB. V5 and V6 show paced beats. V.~ shows a QS pattern. This ECG is compatible with the diagnosis of left posterior hemiblock and RBBB. FIG. 2
cardiovascular collapse. She had been in apparent good health until three days prior to admission when she started complaining of headaches. The day prior to admission, she was noted to be having generalized tonic seizures during sleep, lasting only a few minutes. The patient had three subsequent seizures. On arrival at the hospital, she was nonresponsive, the blood pressure was unrecordable, the pulses were nonpalpable, and there were occasional faint heart sounds. The electrocardiogram revealed complete heart block with occasional ventricular beats (Fig. 2, A). Isoproterenol infusion resulted in immediate increase of heart rate to 80 per minute and clinical improvement was marked. A temporary transvenous pacemaker catheter was immediately positioned in the right ventricular apex. A few minutes after effective pacing with a demand Medtronic unit was established, the
patient was fully conscious and alert. No precordial murmur was heard. Physical examination was normal. The chest x-ray revealed a normal heart size and venous congestion had not occurred. The electrocardiogram on admission revealed complete heart block, atrial rate 145/mt; variable ventricular rate between 20 to 50/mt and wide QRS complexes of varying shapes in the same lead suggestive of a changing low ventricular focus. Figure 2 demonstrates three different patterns of conduction defects. Panel B shows a pattern of LAH with RBBB and panel C is suggestive of left posterior hemiblock with RBBB. Most laboratory tests gave normal results. A throat culture was positive for beta hemolytic streptococci. The initial ASO titer of 166 increased to 373 at two weeks after admission; sedimentation rate 10; CPK 27; SGOT declined from initial level of 440 to 154 to 30; LDH
347
Downloaded from cpj.sagepub.com at NANYANG TECH UNIV LIBRARY on May 24, 2015
declined from initial level of 1,500 to 1,440 to 1,200 to 660; isoenzyme LDH for heart was increased. The complement fixation titers for herpes, influenza A & B, and mycoplasma were
negative. The hospital course was uneventful. Serial electrocardiograms revealed a pattern of RBBB and LAH. Upon removal of the pacing catheter the 9th day, she maintained a stable sinus and was discharged. She continues to remain asymptomatic 18 months after the onset of her initial symptoms despite persistence of RBBB with LAH. on
rhythm
Discussion
,
The patient in Case 1 had Stokes-Adams attacks following a brief illness probably viral in origin. His throat culture grew Staphylococcus aureus. However, his blood cultures remained negative and the course of his illness was not characteristic of staphylococcal septicemia or endocarditis with heart block. The electrocardiograms revealed a pattern of complete atrioventricular block which was intermittent and resulted in syncope and seizures. Spontaneous improvement to 2:1I A.V. block and then to sinus rhythm was consistently seen. The electrocardiographic pattern during atrioventricular conduction was compatible with LAH with RBBB. We were unable to record a pattern of left posterior hemiblock. However, it is assumed that intermittent interference with conduction through the left posterior fascicle resulted in complete heart block, i.e., trifascicular block. The course of his illness is suggestive of complete recovery of left posterior fascicle, while the left anterior fascicle and the right bundle branch seem to have been permanently affected. The patient in Case 2 presented with cardiovascular collapse caused by very slow heart rate. She also had a brief preceding illness, probably viral in nature. The throat culture grew beta hemolytic Streptococcus and ASO titers were mildly elevated. She did not develop valvulitis or other manifestations of rheumatic fever. The electrocardiogram revealed three distinct patterns. First, intermittent complete blockage of atrioventricular
conduction resulted in very slow heart rate and seizures. Spontaneous recovery to a pattern of sinus rhythm with LAH and RBBB occurred most of the time. However, on one occasion, a pattern of left posterior hemiblock with RBBB was recorded. This phenomenon is compatible with the assumption that complete anterograde atrioventricular conduction block was secondary to the conduction defect in the three main bundles, i.e., trifascicular block. The course of this patient’s illness is also suggestive of eventual recovery of the left posterior fascicle, while the right bundle and the left anterior fascicle seem to have been permanently affected. Temporary transvenous demand pacing proved lifesaving in both patients. Although clinical recovery was full, they continue to show RBBB and LAH months after the onset of their symptoms. Both are now attending school and have had no CNS or cardiac symptoms since their discharge from the hospital. Their long-term prognosis is guarded, as they seem more vulnerable to develop complete heart block. In summary, these two cases should alert the practicing physicians to acquired complete heart block presenting as a seizure disorder. Recognition of the basic problem and rapid institution of pacemaker therapy could prove lifesaving. The diagnosis of heart block should probably be considered in any patient with atypical seizures.
References 1.
and Lee, P. L.: Complete atrioventricular heart block secondary to acute myocarditis requiring intracardiac pacing. J. Pediatr. 78:
Johnson, L. J., 312, 1971.
S. J.: Atrioventricular node inflammation—mechanism of sudden death in protracted meningococcemia. N. Engl. J. Med. 286: 1091, 1972. 3. Clinicopathologic conference—Case 20-1972. N. Engl. J. Med. 286: 1100, 1972. 4. Wenger, N. K.: Infectious myocarditis. In Cardiovascular Clinics, Burch G. E., Ed. Vol. 4, Number 1, pp. 168-185. Philadelphia, F. A. Davis Co., 1972. 5. Harvey, P.: Clinical aspects of cardiac tumors. Am. J. Cardiol. 21: 328, 1968. 2.
Robboy,
348
Downloaded from cpj.sagepub.com at NANYANG TECH UNIV LIBRARY on May 24, 2015
