Syncope—Brain or Heart? A Case Report MICHAEL FREITAG,** BENGT HINDFKLT,* BENGT W. JOHANSSON,** and INGMAR ROSEN+
HAKAN NILSSON,*
From the Departments of *Neurology, **Internal Medicine (Cardiac Section), and tClinical Neurophysiology, Malmo General Hospital, University of Lund, Malmo, Sweden NILSSON, H., ET AL.: Syncope—Brain or Heart? A Case Report. A 44-year-old man suffered from recurrent
episodes of unconsciousness, without any other concomifanl manifestations. After routine workup, EEG and CT bad proven nondiagnostic, prolonged HoJter monitoring revealed a single episode of asystole, lasting 7.6 seconds. A pacemaker was inserted buf did not aboJish his episodic syncope. Subsequently, long-term EEG recording revealed epileptiform activity witb independent foci in botb temporal lobes. Antiepileptic treatment relieved the patient of his symptoms. This case illustrates the intimate relationship between tbe heart and tbe brain tbat sometimes lies behind syncope. (PACE, Vol. 15, June 1992} syncope, temporaJ-lobe epilepsia, bradycardia
Introduction Sudden attacks of unconsciousness, with loss of muscle tone, may be due to a variety of causes. Frequently, the patient's history provides a diagnostic hint. However, a witness' report and physical examination, particularly of the cardiovascular and nervous systems, are essential for reaching an accurate diagnosis, which then usually has to be verified by appropriate laboratory tests such as ECG and EEG recordings. The laboratory tests may sometimes be initially normal and long-term ECG and EEG recordings may be necessary. These should include at least one episode of syncope to be considered diagnostic. However, in rare cases, as illustrated by this case report, discrepancies between the laboratory findings and the clinical course may make interpretation of the underlying pathophysiology difficult. Case Report A previously healthy 44-year-old male suffered three brief episodes of unconsciousness over
Address for reprints: Hikan Nilsson, M.D., Department of Neurology, Maimo Generai Hospitai, S-214 01 Maimo, Sweden, Received November 6.1991; revision January 7.1992; accepted February 3, 1992.
PACE, Vol. 15
a week. He sought medical attention after the last episode. Cardiological and neurological examinations were normal. Investigations, including 3 days of continuous ECG recording, a routine EEG recording, and a CT of the brain, were also normal. The attacks did not recur during his week in hospital. He was discharged without treatment. One month later another attack occurred. Witnesses reported that the patient appeared completely normal until he suddenly lost consciousness and fell to the ground. He did not look pale, did not turn cyanotic, nor were any fits reported. The patient recovered completely within 10 seconds of losing consciousness. Reinvestigation verified the normal findings mentioned above. A combined long-term ECG and sphenoidal EEG recording was undertaken. After 1 week without symptoms, the EEG recording was stopped. The ECG recording continued, and after 14 days of continuous registration the patient suddenly became unconscious in exactly the same manner as earlier reported. The ECC revealed a sinus arrest of 7.6 seconds, followed by a junctional beat and another sinus arrest of 3.8 seconds (Eig. 1). The recording also disclosed several asymptomatic ventricular extrasystoles. The patient fulfilled the criteria for the diagnosis of sick sinus syndrome and a pacemaker of VVI-type (Medtronic 5941, Medtronic, Inc., Minneapolis, MN, USA) was inserted. However, 3 weeks later, while driving his car, he sud-
June 1992
957
NILSSON, ET AL.
Figure 1. ECG tracing showing sinus arrest.
denly lost consciousness without any concomitant symptoms. He crashed into other cars and subsequently lost his driving license. Malfunctioning of the pacemaker or an episode of ventricular tachycardia was suspected. Two months of continuous ECG recording followed. The patient suffered several brief episodes of unconsciousness during this time, but the ECG recordings remained normal during these episodes. The ECG revealed only short bouts of ventricular tachycardia, unaccompanied by any symptoms. The suspicion of epilepsy was thus raised again. During 4 days of continuous EEC recording by sphenoidal and scalp electrodes, one single sharp wave over the left temporal lobe was registered. The episodes of unconsciousness became more frequent, occurring sometimes once a week, sometimes every day. Normally, the attacks were only noticed by the patient's wife and not by tbe patient or his workmates. These attacks were described as episodes of 10-20 seconds of absence without motor symptoms. The patient had amnesia for these brief attacks. Carbamazepin did not decrease the frequency of attacks when tried over a 6-month period. He was then switched over to sodium valproate, but without obvious benefit. At this time, 1 % years after the attacks had begun, long-term EEG (with sphenoidal electrodes) showed independent bursts of sharp waves over both temporal lobes (Fig. 2). His medication was therefore changed once again, this time to carbamazepin combined with gamma-vinyl-GABA (vigabatrin). With this regimen, the patient has been symptom-free for 12 months.
Discussion Dysfunction of the heart or the brain may each cause syncope. Both organs are functionally inter-
958
dependent, which explains the diagnostic difficulties frequently encountered in clinical practice.'""* Eor instance, cardiac arrhythmia may lead to decreased circulation to the brain, which can manifest itself as syncope, sometimes with seizures of the myoclonic type.'^"" Such circulatory impairment can result in a localized ischemic lesion, which may subsequently turn into an epileptic focus. Conversely, seizures may induce a powerful sympathetic drive, with potentially harmful effects on the heart. Temporal lobe epilepsy can also induce bradycardia via the vagus."^"^^ The type of heart rate change in a patient during seizures of temporal lobe origin remains fairly constant from one attack to the other.^'' The syncope episodes in this case were not typical of generalized epileptic seizures. The normal findings on the neurological examination, CT scan of the brain, and EEG recording also made a primary diagnosis of epilepsy unlikely, This was the reason for the continuous ECG recording over a 2-week period, until a registration during syncope was documented.^^ The asystole was suggestive of primary heart disease, i.e., sick sinus syndrome. When the pacemaker failed to abolish his attacks and after tachycardia and a malfunctioning pacemaker had been ruled out the suspicion of epilepsy was again raised. This suspicion could be supported only after another period of long-term ambulatory EEG recording [Fig. 2) There are known areas in the brain tbat when stimulated will give rise to cardiac arrhythmias. This applies particularly to the posterior bypothalamus where stimulation may induce ventricular fibrillation.^''-i** On the other hand, slowing of tbe sinus node and even sinus arrest may occur with stimulation of the anterior hypothalamus or tbe insular cortex, tbe impulses being transmitted to the heart via the dorsal vagal motor nucleus and the vagal nerve.^^""^^
June 1992
PACE, Vol. 15
SYNCOPE—BRAIN OR HEART?
I
.
I
t
/*\/'*wA/\fv'-'>*(^^'^.U/^^
Figure 2. EEG recording with bilateral bursts of sharp waves over the temporaJ lobes.
Patients with sinus arrest in association with seizures have been documented to have both uniand bilateral epileptiform foci within the temporal lobes.^^"^^ The bilateral epileptiform foci in our case do not provide a definite explanation for the episodes of asystole. What comes first in an individual patient, dysfunction of the heart or dysfunction of the brain, may remain unresolved, even after an extensive workup. The only way to
PACE. Vol. 15
answer the question is through simultaneous ECG and EEG recordings, preferably including sphenoidal electrodes, during an attack. Our patient provides evidence of primary disease in the heart and the brain. Both diseases needed to be treated before a satisfactory outcome was achieved. The best way to deal with cases like ours is through close cooperation between the cardiologist and the neurologist.
June 1992
NILSSON, ET AL.
References
10.
11. 12.
13.
960
Gilchrist JM. Arrhythmogenic seizures: Diagnosis by simultaneous EEG/ECG recording. Neurology 1985; 35:1503-1506. Howell SLJ, Blumhardt LD. Cardiac asystole associated with epileptic seizures: A case report with simultaneous EEG and ECG. J Neurol Neurosurg Psychiatry 1985; 52:795-798. Nousiainen U. Mervaala E, Uusitupa M, et al. Cardiac arrhythmias in the differential diagnosis of epilepsy. J Neurol 1989; 236:93-96. Kapoor WN, Karpf M, Wieand S. et al. A prospective evaluation and follow-up of patients with syncope. New Engl J Med 1983; 309:197-204. Duvernoy WFC, Nair MRS, Zobl EG. Convulsive disorder mimicked by prolonged asystole and cured by permanent pacing. Heart and Lung 1980; 9:711-714. Blumhardt LD. Ambulatory ECG and EEC monitoring in the differential diagnosis of cardiac and cerebral dysrhythmias. Adv Neurol 1986; 46:183-202. Kielson NJ, Selman }, Magrill J. Epilepsy due to cardiac disease. Neurology 1987; 37(Suppl. 1):91. Leestma JE, Kalelkar MB, Teas SS, et al. Sudden unexpected death associated with seizures: Analysis of 66 cases. Epilepsia 1984; 25:84-88. Jay GW, Leestma JE. Sudden death in epilepsy: A comprehensive review of the literature and proposed mechanisms. Acta Neurol Scand 1981: 63(Suppl 82):l-66. Nousiainen U, Mervaala E, Ylinen A, et al. The importance of the electrocardiogram in ambulatory electroencephalographic recordings. Arch Neurol 1989; 46:1171-1174. Erickson TC. Cardiac activity during epileptic seizures. Arch Neurol Psychiat 1939; 41:511-518. Blumhardt LD, Smith PEM, Owen L. Electrocardiographic accompaniments of temporal lobe epileptic seizures. Lancet 1986; 1:1051-1056. Leitch MB, Klein G, Yee R, et al. Neurally mediated
14. 15. 16. 17. 18. 19.
20. 21. 22. 23. 24. 25. 26.
June 1992
syncope and atrial fibrillation. New Engl J Med 1991; 324:495-496. Smith PEM, Howell SJL, Owen L, et al. Profiles of instant heart rate during partial seizures. Electroenc Glin Neuropbysiol 1989; 72:207-217. Johansson BW. Long-term EGG in ambulatory clinical practice. Eur J Cardiol 1977; 5(l):39-48, Oppenheimer MA, Cechetto DF, Hachinski VC. Cerebrogenic cardiac arrhythmias. Arch Neurol 1990; 47:513-519. Lown B, Verrier RL. Neural activity and ventricnlar fibrillation. New Engl J Med 1976; 294:1165-1170. Verrier RL, Calvert A, Lown B. Effect of posterior hypothalamir. stimulation on ventricular fibrillation threshold. Am J Pbysiol 1975; 228:923-927. Evans DE, Cillis RA. Reflex mechanisms involved in cardiac arrhythmias induced by hypothalamic stimulation. Am I Physiol 1987; 234(2):H119H209. Ruggiero DA, Mraovitch S, Granata AR, et al. A role in insular cortex in cardiovascular function. J Comp Neurol 1982; 257:189-207. Mameii P, Malmeli O, Tolu E, et al. Neurogenic myocardial arrhythmias in experimental focal epilepsy. Epilepsia 1988; 29:74-82. Smaje JC, Davidson G, Teasdale GM. Sino-atrial arrest due to temporal lobe epilepsy. J Neurol Neurosurg Psychiatry 1987; 50:112-113. Phizackerley PJR, Poole EW, Whitty CWM. Sinoauricular heart block as an epileptic manifestation. Epilepsia 1954; 3:89-91. Kiok MC, Terrence CF, Fromm CH, et al. Sinus arrest in epilepsy. Neurology 1986; 36:115-116. Devinsky O, Price BH, Gohen SL Cardiac manifestations of complex partial seizures. Am ] Med 1986; 80:195-202. Pritchett ELG, McNamara JO. Gallagher JJ. Arrhytbmogenic epilepsy: An hypothesis. Am Heart J 1980; 100:683-688,
PACE. Vol. 15
HAKAN NILSSON,*
From the Departments of *Neurology, **Internal Medicine (Cardiac Section), and tClinical Neurophysiology, Malmo General Hospital, University of Lund, Malmo, Sweden NILSSON, H., ET AL.: Syncope—Brain or Heart? A Case Report. A 44-year-old man suffered from recurrent
episodes of unconsciousness, without any other concomifanl manifestations. After routine workup, EEG and CT bad proven nondiagnostic, prolonged HoJter monitoring revealed a single episode of asystole, lasting 7.6 seconds. A pacemaker was inserted buf did not aboJish his episodic syncope. Subsequently, long-term EEG recording revealed epileptiform activity witb independent foci in botb temporal lobes. Antiepileptic treatment relieved the patient of his symptoms. This case illustrates the intimate relationship between tbe heart and tbe brain tbat sometimes lies behind syncope. (PACE, Vol. 15, June 1992} syncope, temporaJ-lobe epilepsia, bradycardia
Introduction Sudden attacks of unconsciousness, with loss of muscle tone, may be due to a variety of causes. Frequently, the patient's history provides a diagnostic hint. However, a witness' report and physical examination, particularly of the cardiovascular and nervous systems, are essential for reaching an accurate diagnosis, which then usually has to be verified by appropriate laboratory tests such as ECG and EEG recordings. The laboratory tests may sometimes be initially normal and long-term ECG and EEG recordings may be necessary. These should include at least one episode of syncope to be considered diagnostic. However, in rare cases, as illustrated by this case report, discrepancies between the laboratory findings and the clinical course may make interpretation of the underlying pathophysiology difficult. Case Report A previously healthy 44-year-old male suffered three brief episodes of unconsciousness over
Address for reprints: Hikan Nilsson, M.D., Department of Neurology, Maimo Generai Hospitai, S-214 01 Maimo, Sweden, Received November 6.1991; revision January 7.1992; accepted February 3, 1992.
PACE, Vol. 15
a week. He sought medical attention after the last episode. Cardiological and neurological examinations were normal. Investigations, including 3 days of continuous ECG recording, a routine EEG recording, and a CT of the brain, were also normal. The attacks did not recur during his week in hospital. He was discharged without treatment. One month later another attack occurred. Witnesses reported that the patient appeared completely normal until he suddenly lost consciousness and fell to the ground. He did not look pale, did not turn cyanotic, nor were any fits reported. The patient recovered completely within 10 seconds of losing consciousness. Reinvestigation verified the normal findings mentioned above. A combined long-term ECG and sphenoidal EEG recording was undertaken. After 1 week without symptoms, the EEG recording was stopped. The ECG recording continued, and after 14 days of continuous registration the patient suddenly became unconscious in exactly the same manner as earlier reported. The ECC revealed a sinus arrest of 7.6 seconds, followed by a junctional beat and another sinus arrest of 3.8 seconds (Eig. 1). The recording also disclosed several asymptomatic ventricular extrasystoles. The patient fulfilled the criteria for the diagnosis of sick sinus syndrome and a pacemaker of VVI-type (Medtronic 5941, Medtronic, Inc., Minneapolis, MN, USA) was inserted. However, 3 weeks later, while driving his car, he sud-
June 1992
957
NILSSON, ET AL.
Figure 1. ECG tracing showing sinus arrest.
denly lost consciousness without any concomitant symptoms. He crashed into other cars and subsequently lost his driving license. Malfunctioning of the pacemaker or an episode of ventricular tachycardia was suspected. Two months of continuous ECG recording followed. The patient suffered several brief episodes of unconsciousness during this time, but the ECG recordings remained normal during these episodes. The ECG revealed only short bouts of ventricular tachycardia, unaccompanied by any symptoms. The suspicion of epilepsy was thus raised again. During 4 days of continuous EEC recording by sphenoidal and scalp electrodes, one single sharp wave over the left temporal lobe was registered. The episodes of unconsciousness became more frequent, occurring sometimes once a week, sometimes every day. Normally, the attacks were only noticed by the patient's wife and not by tbe patient or his workmates. These attacks were described as episodes of 10-20 seconds of absence without motor symptoms. The patient had amnesia for these brief attacks. Carbamazepin did not decrease the frequency of attacks when tried over a 6-month period. He was then switched over to sodium valproate, but without obvious benefit. At this time, 1 % years after the attacks had begun, long-term EEG (with sphenoidal electrodes) showed independent bursts of sharp waves over both temporal lobes (Fig. 2). His medication was therefore changed once again, this time to carbamazepin combined with gamma-vinyl-GABA (vigabatrin). With this regimen, the patient has been symptom-free for 12 months.
Discussion Dysfunction of the heart or the brain may each cause syncope. Both organs are functionally inter-
958
dependent, which explains the diagnostic difficulties frequently encountered in clinical practice.'""* Eor instance, cardiac arrhythmia may lead to decreased circulation to the brain, which can manifest itself as syncope, sometimes with seizures of the myoclonic type.'^"" Such circulatory impairment can result in a localized ischemic lesion, which may subsequently turn into an epileptic focus. Conversely, seizures may induce a powerful sympathetic drive, with potentially harmful effects on the heart. Temporal lobe epilepsy can also induce bradycardia via the vagus."^"^^ The type of heart rate change in a patient during seizures of temporal lobe origin remains fairly constant from one attack to the other.^'' The syncope episodes in this case were not typical of generalized epileptic seizures. The normal findings on the neurological examination, CT scan of the brain, and EEG recording also made a primary diagnosis of epilepsy unlikely, This was the reason for the continuous ECG recording over a 2-week period, until a registration during syncope was documented.^^ The asystole was suggestive of primary heart disease, i.e., sick sinus syndrome. When the pacemaker failed to abolish his attacks and after tachycardia and a malfunctioning pacemaker had been ruled out the suspicion of epilepsy was again raised. This suspicion could be supported only after another period of long-term ambulatory EEG recording [Fig. 2) There are known areas in the brain tbat when stimulated will give rise to cardiac arrhythmias. This applies particularly to the posterior bypothalamus where stimulation may induce ventricular fibrillation.^''-i** On the other hand, slowing of tbe sinus node and even sinus arrest may occur with stimulation of the anterior hypothalamus or tbe insular cortex, tbe impulses being transmitted to the heart via the dorsal vagal motor nucleus and the vagal nerve.^^""^^
June 1992
PACE, Vol. 15
SYNCOPE—BRAIN OR HEART?
I
.
I
t
/*\/'*wA/\fv'-'>*(^^'^.U/^^
Figure 2. EEG recording with bilateral bursts of sharp waves over the temporaJ lobes.
Patients with sinus arrest in association with seizures have been documented to have both uniand bilateral epileptiform foci within the temporal lobes.^^"^^ The bilateral epileptiform foci in our case do not provide a definite explanation for the episodes of asystole. What comes first in an individual patient, dysfunction of the heart or dysfunction of the brain, may remain unresolved, even after an extensive workup. The only way to
PACE. Vol. 15
answer the question is through simultaneous ECG and EEG recordings, preferably including sphenoidal electrodes, during an attack. Our patient provides evidence of primary disease in the heart and the brain. Both diseases needed to be treated before a satisfactory outcome was achieved. The best way to deal with cases like ours is through close cooperation between the cardiologist and the neurologist.
June 1992
NILSSON, ET AL.
References
10.
11. 12.
13.
960
Gilchrist JM. Arrhythmogenic seizures: Diagnosis by simultaneous EEG/ECG recording. Neurology 1985; 35:1503-1506. Howell SLJ, Blumhardt LD. Cardiac asystole associated with epileptic seizures: A case report with simultaneous EEG and ECG. J Neurol Neurosurg Psychiatry 1985; 52:795-798. Nousiainen U. Mervaala E, Uusitupa M, et al. Cardiac arrhythmias in the differential diagnosis of epilepsy. J Neurol 1989; 236:93-96. Kapoor WN, Karpf M, Wieand S. et al. A prospective evaluation and follow-up of patients with syncope. New Engl J Med 1983; 309:197-204. Duvernoy WFC, Nair MRS, Zobl EG. Convulsive disorder mimicked by prolonged asystole and cured by permanent pacing. Heart and Lung 1980; 9:711-714. Blumhardt LD. Ambulatory ECG and EEC monitoring in the differential diagnosis of cardiac and cerebral dysrhythmias. Adv Neurol 1986; 46:183-202. Kielson NJ, Selman }, Magrill J. Epilepsy due to cardiac disease. Neurology 1987; 37(Suppl. 1):91. Leestma JE, Kalelkar MB, Teas SS, et al. Sudden unexpected death associated with seizures: Analysis of 66 cases. Epilepsia 1984; 25:84-88. Jay GW, Leestma JE. Sudden death in epilepsy: A comprehensive review of the literature and proposed mechanisms. Acta Neurol Scand 1981: 63(Suppl 82):l-66. Nousiainen U, Mervaala E, Ylinen A, et al. The importance of the electrocardiogram in ambulatory electroencephalographic recordings. Arch Neurol 1989; 46:1171-1174. Erickson TC. Cardiac activity during epileptic seizures. Arch Neurol Psychiat 1939; 41:511-518. Blumhardt LD, Smith PEM, Owen L. Electrocardiographic accompaniments of temporal lobe epileptic seizures. Lancet 1986; 1:1051-1056. Leitch MB, Klein G, Yee R, et al. Neurally mediated
14. 15. 16. 17. 18. 19.
20. 21. 22. 23. 24. 25. 26.
June 1992
syncope and atrial fibrillation. New Engl J Med 1991; 324:495-496. Smith PEM, Howell SJL, Owen L, et al. Profiles of instant heart rate during partial seizures. Electroenc Glin Neuropbysiol 1989; 72:207-217. Johansson BW. Long-term EGG in ambulatory clinical practice. Eur J Cardiol 1977; 5(l):39-48, Oppenheimer MA, Cechetto DF, Hachinski VC. Cerebrogenic cardiac arrhythmias. Arch Neurol 1990; 47:513-519. Lown B, Verrier RL. Neural activity and ventricnlar fibrillation. New Engl J Med 1976; 294:1165-1170. Verrier RL, Calvert A, Lown B. Effect of posterior hypothalamir. stimulation on ventricular fibrillation threshold. Am J Pbysiol 1975; 228:923-927. Evans DE, Cillis RA. Reflex mechanisms involved in cardiac arrhythmias induced by hypothalamic stimulation. Am I Physiol 1987; 234(2):H119H209. Ruggiero DA, Mraovitch S, Granata AR, et al. A role in insular cortex in cardiovascular function. J Comp Neurol 1982; 257:189-207. Mameii P, Malmeli O, Tolu E, et al. Neurogenic myocardial arrhythmias in experimental focal epilepsy. Epilepsia 1988; 29:74-82. Smaje JC, Davidson G, Teasdale GM. Sino-atrial arrest due to temporal lobe epilepsy. J Neurol Neurosurg Psychiatry 1987; 50:112-113. Phizackerley PJR, Poole EW, Whitty CWM. Sinoauricular heart block as an epileptic manifestation. Epilepsia 1954; 3:89-91. Kiok MC, Terrence CF, Fromm CH, et al. Sinus arrest in epilepsy. Neurology 1986; 36:115-116. Devinsky O, Price BH, Gohen SL Cardiac manifestations of complex partial seizures. Am ] Med 1986; 80:195-202. Pritchett ELG, McNamara JO. Gallagher JJ. Arrhytbmogenic epilepsy: An hypothesis. Am Heart J 1980; 100:683-688,
PACE. Vol. 15
