110
arch using the left subclavian artery as a graft. Tabak et al. [2] reported two patients with this combination of anomalies. One of these patients died before surgery was undertaken and the other patient was operated succesfully, but in a two-stage repair. During the first step the isthmic obstruction was relieved, the ductus was ligated and the aortopulmonary window was plicated via a left thoracotomy. The second step consisted of final closure of the aortopulmonary window via a median sternotomy and using deep hypothermia. Ding et al. [3] reported one 3-year-old patient in which he used a Dacron baffle both to close the aortopulmonary window and to direct blood to the right pulmonary artery. The interrupted aortic arch was repaired by direct anastomosis [3]. Our report concerning the thirteenth reported case and the fifth case with succesful repair, adds a new method of one-stage repair to other surgical corrections of this rare combination of cardiac anomalies. Stenosis at the site of the anastomosis between the
aortic arch and the descending aorta is a potential complication one has to be aware of. This can be treated adequately by percutaneous transluminal balloon angioplasty with a low complication rate [4]. References Berry TE, Bharati S, Muster AJ et al. Distal aortopulmonary septal defect, aortic origin of the right pulmonary artery, intact ventricular septum, patent ductus arteriosus and hypoplasia of the aortic isthmus: a newly recognized syndrome. Am J Cardiol 1982;49:108-116. Tabak C, Moskowitz W, Wagner H, Weinberg P, Edmunds LH. Aortopulmonary window and aortic isthmic hypoplasia. J Thorac Cardiovasc Surg 1983;86:273-279. Ding W-X, Su Z-K, Cao D-F, Jonas RA. One-stage repair of absence of the aortopulmonary septum and interrupted aortic arch. Ann Thorac Surg 1990;49:664-666. Saul JP, Keane JF, Fellows KE, Lock JE. Balloon dilatation angioplasty of postoperative aortic coarctation. J Am Coil Cardiol 19867:117A.
International Journal of Cardiology, 34 (1992) 110-112
0 1992 Elsevier Science Publishers B.V. All rights reserved 0167-5273/92/$05.00
CARD10 13637
Electrocardiographic
artifact with a transcutaneous nerve stimulation unit Paul J. Hauptman
electrical
and M. Raza
Department of Cardiology, Mount Sinai Hospital, New York, New York, U.S.A
We describe an unusual electrocardiographic artifact in a patient with a transcutaneous electrical nerve stimulation unit. The a&fact, consisting of low amplitude high frequency deflections, can be misinterpreted as a runaway pacemaker. Key words: Electrocardiogram;
Artifact
Correspondence to: P.J. Hauptman, Dept. of Cardiology, Mount Sinai Hospital, One Gustave L. Levy Place, New York, NY 10029,
U.S.A.
111
Introduction A variety of electrocardiographic artifacts have been described simulating abnormal complexes and arrhythmias. Well recognized etiologies include motion artifact from tremors, involuntary muscle contractions, broken leads and 60-cycle alternating current interference [l]. Rarer causes have included oxygen tubing overlying the chest wall, placement of the electrocardiographic lead over an arteriovenous fistula and a malfunctioning electric watch [2]. Recent reports have described artifacts during intraoperative monitoring of somatosensory evoked potentials [3] and with a parasternally placed transcutaneous electrical nerve stimulation unit in an intensive care unit setting [4]. We report an artifact of an implanted transcutaneous electrical nerve stimulation unit detected on a routine 12-lead electrocardiogram in an ambulatory patient with nerve stimulation electrodes placed over the lower back. Case Report The patient is a 63-year-old white male who was diagnosed with a spinal cord tumor in 1955 and underwent a T5-7 laminectomy with resection in 1956. He subsequently developed intractable chronic lower back pain. A transcutaneous electrical nerve stimulation unit was implanted in November 1990 with the stimulating electrode inserted at the level of Tll through an epidural approach and with stimulation set at the rate of 50 per second. As part of a routine medical examination, a 1Zlead electrocardiogram was obtained, which revealed multiple deflections at a rate of 50 per second throughout the cardiac cycle, most marked in leads 111 and aVF (Fig. 1). A cardiologist was consulted. The leads were appropriately placed and the equipment was grounded without loose or broken leads. When the transcutaneous electrical nerve stimulation
Fig. 2. Tracing of lead aVF with unit deactivated (see text).
unit was deactivated by use of a magnet, the deflections were no longer present (Fig. 2) and reappeared on removal of the magnet. The electrocardiogram was otherwise normal. Discussion Transcutaneous nerve stimulation units have been used for post-operative pain control and in many chronic pain syndromes including the lower back in sciatica. We describe the finding of multiple high frequency pseudopacemaker spikes in the inferior leads in a patient with a transcutaneous electrical nerve stimulation unit. A previous report [4] demonstrated these spikes with parasternally placed transcutaneous electrical nerve stimulation electrodes. The prominence of the spikes in the inferior leads is likely due to the parallel nature of the vector of the discharges to the inferior lead axes. A potential pitfall in the interpretation of the artifact is its semblance to the electrocardiographic manifestation of the so-called runaway pacemaker [5]. The placement of transcutaneous electrical nerve stimulation units in locations remote from the chest can cause significant artifacts in the surface electrocardiogram and can be easily diagnosed by temporary deactivation of the unit with a magnet.
The authors thank Dr. W.A. Bauman for permission to report this case and Drs. Paul Schweitzer and Eric Stern for their valuable comments.
References
Fig. 1. Tracing of lead aVF with unit activated (see text).
1 Chung E. Electrocardiography: practical applications with vectorial principles. Philadelphia: Harper & Row;1980:641. 2 Lesch M, Greene HL. Electrocardiographic artifact due to malfunction of an electric watch. JAMA 1974;228:26.
112 Legatt AD, Frost EAM. EKG artifacts during intraoperative evoked potential monitoring. Anesthesiology 1989;70: 559. Kimberley APS, Soni N, Williams TR. Transcutaneous nerve stimulation and the electrocardiograph. Anaesth Intens Care 1987;15:358-359.
5 Yang SS, Goldberg H. Electrocardiographic recognition of pacemakers. In: Morse D, Steiner RM, Parsonnet V, eds. A guide to cardiac pacemakers. Philade1phia:F.A. Davis Co, 1983;71-73.
International Journal of Cardiology, 34 (1992) 112-114
0 1992 Elsevier Science Publishers B.V. All rights reserved 0167-5273/92/$05.00
CARD10 13638
A successful pregnancy in a patient with congenital tricuspid stenosis and a patent oval foramen S.Y. Chuah ‘, J. Hughes-Nurse
2 and D.B. Rowlands ’
’ Department of Medicine, Peterborough District Hospital, Peterborough, Cambridgeshire, U.K.; ’ Department of Obstetrics and Gynaecology, Peterborough District Hospital, Peterborough, Cambridgeshire, U.K.
(Received 27 March 1991; revision accepted 22 July 1991)
Patients with cyanotic congenital heart disease who have obstruction proximal to the pulmonary arteries and, hence, do not develop pulmonary hypertension, can go through pregnancy successfully, if the pregnancy and delivery are adequately cared for, with possible complications in mind. We report a successful pregnancy in a woman with congenital tricuspid stenosis and a patent oval foramen. Key words: Pregnancy;
Tricuspid
stenosis;
Patent
oval foramen
Introduction
Case Report
Tricuspid stenosis almost never occurs in isolation. Rheumatic tricuspid stenosis seldom occurs without mitral stenosis [l]. Our patient had congenital tricuspid stenosis and patent oval foramen.
The
murmur.
patient
presented
at 3$ years
She was more dyspnoeic
with
than
a heart
her peers.
There was no squatting, syncope or frequent chest infections. She had centrai cyanosis, clubbing and a high-pitched ejection systolic murmur at the left sternal edge with normal heart sounds. At 13, prominent
“a” wave was noted in the jugular venous pulse. Chest radiograph showed oligaemic lung fields with right atria1 enlargement. Electrocardiography showed left Correspondence ro: Dr. S.Y. Chuah, Leicester Hospital, Leicester LE5 4PW, U.K.
General
axis deviation. She enjoyed
a normal
life and worked as a nurse. At
arch using the left subclavian artery as a graft. Tabak et al. [2] reported two patients with this combination of anomalies. One of these patients died before surgery was undertaken and the other patient was operated succesfully, but in a two-stage repair. During the first step the isthmic obstruction was relieved, the ductus was ligated and the aortopulmonary window was plicated via a left thoracotomy. The second step consisted of final closure of the aortopulmonary window via a median sternotomy and using deep hypothermia. Ding et al. [3] reported one 3-year-old patient in which he used a Dacron baffle both to close the aortopulmonary window and to direct blood to the right pulmonary artery. The interrupted aortic arch was repaired by direct anastomosis [3]. Our report concerning the thirteenth reported case and the fifth case with succesful repair, adds a new method of one-stage repair to other surgical corrections of this rare combination of cardiac anomalies. Stenosis at the site of the anastomosis between the
aortic arch and the descending aorta is a potential complication one has to be aware of. This can be treated adequately by percutaneous transluminal balloon angioplasty with a low complication rate [4]. References Berry TE, Bharati S, Muster AJ et al. Distal aortopulmonary septal defect, aortic origin of the right pulmonary artery, intact ventricular septum, patent ductus arteriosus and hypoplasia of the aortic isthmus: a newly recognized syndrome. Am J Cardiol 1982;49:108-116. Tabak C, Moskowitz W, Wagner H, Weinberg P, Edmunds LH. Aortopulmonary window and aortic isthmic hypoplasia. J Thorac Cardiovasc Surg 1983;86:273-279. Ding W-X, Su Z-K, Cao D-F, Jonas RA. One-stage repair of absence of the aortopulmonary septum and interrupted aortic arch. Ann Thorac Surg 1990;49:664-666. Saul JP, Keane JF, Fellows KE, Lock JE. Balloon dilatation angioplasty of postoperative aortic coarctation. J Am Coil Cardiol 19867:117A.
International Journal of Cardiology, 34 (1992) 110-112
0 1992 Elsevier Science Publishers B.V. All rights reserved 0167-5273/92/$05.00
CARD10 13637
Electrocardiographic
artifact with a transcutaneous nerve stimulation unit Paul J. Hauptman
electrical
and M. Raza
Department of Cardiology, Mount Sinai Hospital, New York, New York, U.S.A
We describe an unusual electrocardiographic artifact in a patient with a transcutaneous electrical nerve stimulation unit. The a&fact, consisting of low amplitude high frequency deflections, can be misinterpreted as a runaway pacemaker. Key words: Electrocardiogram;
Artifact
Correspondence to: P.J. Hauptman, Dept. of Cardiology, Mount Sinai Hospital, One Gustave L. Levy Place, New York, NY 10029,
U.S.A.
111
Introduction A variety of electrocardiographic artifacts have been described simulating abnormal complexes and arrhythmias. Well recognized etiologies include motion artifact from tremors, involuntary muscle contractions, broken leads and 60-cycle alternating current interference [l]. Rarer causes have included oxygen tubing overlying the chest wall, placement of the electrocardiographic lead over an arteriovenous fistula and a malfunctioning electric watch [2]. Recent reports have described artifacts during intraoperative monitoring of somatosensory evoked potentials [3] and with a parasternally placed transcutaneous electrical nerve stimulation unit in an intensive care unit setting [4]. We report an artifact of an implanted transcutaneous electrical nerve stimulation unit detected on a routine 12-lead electrocardiogram in an ambulatory patient with nerve stimulation electrodes placed over the lower back. Case Report The patient is a 63-year-old white male who was diagnosed with a spinal cord tumor in 1955 and underwent a T5-7 laminectomy with resection in 1956. He subsequently developed intractable chronic lower back pain. A transcutaneous electrical nerve stimulation unit was implanted in November 1990 with the stimulating electrode inserted at the level of Tll through an epidural approach and with stimulation set at the rate of 50 per second. As part of a routine medical examination, a 1Zlead electrocardiogram was obtained, which revealed multiple deflections at a rate of 50 per second throughout the cardiac cycle, most marked in leads 111 and aVF (Fig. 1). A cardiologist was consulted. The leads were appropriately placed and the equipment was grounded without loose or broken leads. When the transcutaneous electrical nerve stimulation
Fig. 2. Tracing of lead aVF with unit deactivated (see text).
unit was deactivated by use of a magnet, the deflections were no longer present (Fig. 2) and reappeared on removal of the magnet. The electrocardiogram was otherwise normal. Discussion Transcutaneous nerve stimulation units have been used for post-operative pain control and in many chronic pain syndromes including the lower back in sciatica. We describe the finding of multiple high frequency pseudopacemaker spikes in the inferior leads in a patient with a transcutaneous electrical nerve stimulation unit. A previous report [4] demonstrated these spikes with parasternally placed transcutaneous electrical nerve stimulation electrodes. The prominence of the spikes in the inferior leads is likely due to the parallel nature of the vector of the discharges to the inferior lead axes. A potential pitfall in the interpretation of the artifact is its semblance to the electrocardiographic manifestation of the so-called runaway pacemaker [5]. The placement of transcutaneous electrical nerve stimulation units in locations remote from the chest can cause significant artifacts in the surface electrocardiogram and can be easily diagnosed by temporary deactivation of the unit with a magnet.
The authors thank Dr. W.A. Bauman for permission to report this case and Drs. Paul Schweitzer and Eric Stern for their valuable comments.
References
Fig. 1. Tracing of lead aVF with unit activated (see text).
1 Chung E. Electrocardiography: practical applications with vectorial principles. Philadelphia: Harper & Row;1980:641. 2 Lesch M, Greene HL. Electrocardiographic artifact due to malfunction of an electric watch. JAMA 1974;228:26.
112 Legatt AD, Frost EAM. EKG artifacts during intraoperative evoked potential monitoring. Anesthesiology 1989;70: 559. Kimberley APS, Soni N, Williams TR. Transcutaneous nerve stimulation and the electrocardiograph. Anaesth Intens Care 1987;15:358-359.
5 Yang SS, Goldberg H. Electrocardiographic recognition of pacemakers. In: Morse D, Steiner RM, Parsonnet V, eds. A guide to cardiac pacemakers. Philade1phia:F.A. Davis Co, 1983;71-73.
International Journal of Cardiology, 34 (1992) 112-114
0 1992 Elsevier Science Publishers B.V. All rights reserved 0167-5273/92/$05.00
CARD10 13638
A successful pregnancy in a patient with congenital tricuspid stenosis and a patent oval foramen S.Y. Chuah ‘, J. Hughes-Nurse
2 and D.B. Rowlands ’
’ Department of Medicine, Peterborough District Hospital, Peterborough, Cambridgeshire, U.K.; ’ Department of Obstetrics and Gynaecology, Peterborough District Hospital, Peterborough, Cambridgeshire, U.K.
(Received 27 March 1991; revision accepted 22 July 1991)
Patients with cyanotic congenital heart disease who have obstruction proximal to the pulmonary arteries and, hence, do not develop pulmonary hypertension, can go through pregnancy successfully, if the pregnancy and delivery are adequately cared for, with possible complications in mind. We report a successful pregnancy in a woman with congenital tricuspid stenosis and a patent oval foramen. Key words: Pregnancy;
Tricuspid
stenosis;
Patent
oval foramen
Introduction
Case Report
Tricuspid stenosis almost never occurs in isolation. Rheumatic tricuspid stenosis seldom occurs without mitral stenosis [l]. Our patient had congenital tricuspid stenosis and patent oval foramen.
The
murmur.
patient
presented
at 3$ years
She was more dyspnoeic
with
than
a heart
her peers.
There was no squatting, syncope or frequent chest infections. She had centrai cyanosis, clubbing and a high-pitched ejection systolic murmur at the left sternal edge with normal heart sounds. At 13, prominent
“a” wave was noted in the jugular venous pulse. Chest radiograph showed oligaemic lung fields with right atria1 enlargement. Electrocardiography showed left Correspondence ro: Dr. S.Y. Chuah, Leicester Hospital, Leicester LE5 4PW, U.K.
General
axis deviation. She enjoyed
a normal
life and worked as a nurse. At
