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Electrophysiologic features of neonatal paroxysmal atrial tachycardia resulting in Pre- vs postnatal heart failure
708
AAP Program
and Abstracts
American
A NEW ANTITACHYCARDIA PACEMAKER WHICH DIFFERENTIATES SINUS FROM PAROXYSMAL TACHYCARDIA *Paul C. Gillette, M.D. and Alex Zinner, BME, South Carolina Children's Heart Center/Medical University of South Carolina 171 Ashley Avenue Charleston, SC 29425 Previous automatic antitachycardia pacemakers have frequently malfunctioned because their only criteria for determining tachycardia was rate. We implanted a new automatic antitachycardia pacemaker (Intertach) in 3 patients aged 11-19 years postoperative for transposition of the great arteries (2) or atria1 septal defect (1). Each patient had both brady and tachydysrhythmias. Each tachydysrhythmia was atria1 flutter. The pulse generators were implanted using transvenous subclavian puncture technique using a new screw-in bipolar lead. The pulse generators were implanted under the pectoralis muscle. Two of three pacemakers have successfully overdriven several hundred episodes of tachycardia in the 2-3 month follow-up. Each pacemaker has been tested against sinus tachycardia during treadmill testing. Using only rate as a criteria each pacemaker recognized sinus tachycardia as tachycardia. Using rate and rate of change of rate each pacemaker correctly failed to recognize sinus tachycardia as tachycardia. This new automatic antitachycardia pacemaker appears to be able to successfully treat atria1 flutter in pediatric postoperative patients.
PRIMARY ATRIAL TACHYCARDIAS IN CHILDHOOD: RESULTS OF CARDIAC AND SKELETAL MUSCLE BIOPSIES. Ann Dunn&an, M.D., FAAP*; Nancy A. Staley, M.D.; Stephen.A. Smith, M.D.; Mary Ella Pierpont, M.D., Ph.D.; Dianne Judd, David G. Benditt, M.D.; D. Woodrow Benson, Jr., M.D., Ph.D., FAAP. University of Minnesota, Minneapolis, MN We'evaluated
cardiac
(CM)
and
skeletal
muscle
histology in 10 patients (pts), age I to 1X years, with catheterization documented reentry (5 pts) or automatic (5 pts) atria1 tachycardia (primarv atria1 tachycardias). Symptoms included: syncope .(4 pts), palpitations (2 ptsl, heart failure (2 pts), none (2 pts). Light and electron microscopy was performed on ventricular (6 pts) and SM biopsies (10 pts). Serum and SM concentrations of free and acylcarnitine were determined. CM histology was abnormal in all 6 pts examined, and included fibrosis (5 pts); increased lipid (2 pts) (SM)
and
intercalated
discs
(2
pts);
dilated
sarcoplasmic
reticulum (2 pts); dilated mitochondria, myofilament loss, increased glycogen (I pt each). SM histology was abnormal in all pts with increased lipid (7 ots). endomysial fibrosis (4 pts), type I and type II fiber hypotrophy (1 pt each). Serum free and acylcarnitine concentrations were normal in all 10 ots. but SM loneu chain acylcarnitine was low in 7/10 and elevated in l/IO pt. SM short chain acylcarnitine concentration was reduced in l/IO pt. Thus in our pts with primary atria1 tachycardias, CM and SM histologic and carnitine abnormalities were common, suggesting that in otherwise healthy young people, primary atria1 tachycardias may be associated with skeletal and cardiac (i.e., generalized) muscle disease. .
I
Heart
ELECTROPHYSIOLOGIC FEATURES OF NEONATAL PAROXYSMAL ATRIAL TACHYCARDIA RESULTING IN PREVS POSTNATAL HEART FAILURE. Vincent R. Zales, MD*, Athi Narayan, MD, FAAP, Ann Dunnigan, MD, FAAP, D. Woodrow Benson, Jr., MD, PhD, FAAP, Department of Pediatrics, University of Minnesota, Minneapolis, MN the electrophysiologic features of atria1 tachycardia (PAT) in 12 neonates I-14 days) with hydrops fetalis (Pre-CHF) and compared them to 12 NB (age 2-34 days) with postnatal congestive heart failure (Post-CHF). No NB had structural heart disease. All had left ventricular dysfunction. In Pre-CHF NB, PAT was detected at 2X to 35 We
evaluated
paroxysmal (NB) (age
weeks (mean=31) gestation in 7 NB, at delivery in 3 NB, but not until 7 and 14 days postnatally in 2 NB. Spontaneous PAT onset and termination was observed in all Pre-CHF NB. However, in Post-CHF
NB,
a single, Drolonaed PAT During -sinus rhythum, 4/12 Post-CHF NB had evidence of tlon. Durmg postnatal PAT
episode was observed. Pre-CHF NB and 5/12 ventricular oreexcitaevaluation, ‘QRS was normal and the R-P or V-A Interval (from surface or esophageal ECG) was > 80 ms (p NS for Pre-CHF vs Post-CHF NB). However, PAT cycle length (mean?SD) was different for Pre-CHF NB (243i30 ms) vs. Post-CHF NB (208? 19 ms) (p < 0.05). Multiple recurrences and spontaneous terminations of PAT were observed in 12/12 Pre-CHF NB and in no Post-CHF NB. NB with hydrops develop symptoms from multiple PAT recurrences at relatively long cycle length (slow heart rate), whereas Post-CHF NB develop symptoms from sustained PAT at short cycle length (fast heart rate).
TRANSESOPHAGEAL ATRIAL PACING FOR EVALUATION OF PALPITATIONS IN CHILDREN. Ann Dunnigan, M.D., FAAP*; Edward D. Overholt, M.D.; Vincent R. Zales, M.D.; D. Woodrow Benson, Jr., M.D., Ph.D., FAAP. Department of Pediatrics. University of Minnesota, Minneapolis, MN. We evaluated the usefulness of transesophageal atria1 pacing to investigate the etiology - of palpitations in 17 patients (pts) age 5 to 16 vears (mean=9.7) who had had more than 2 episodes of palpitations. All pts had normal sinus rhythm ECGs, and no pt had symptoms during 24-48 hour ambulatory ECG (13 pts) or treadmill ECG (4 ptsl. In an effort to initiate tachycardia, trans-
esophageal atria1 pacing was performed with a bipolar electrode catheter and stimuli of 9.9 ms and IO-20mA using the following atria1 stimulation protocol: extrastimuli in sinus rhythm; refractory periods at 2 train cycle lengths; incremental pacing; bursts of rapid pacing. Isoproterenol (0.01 to 0.1 mcg/kg/min) and atropine (0.04 mg/kg) were administered, and the pacing protocol repeated. During study, tachycardia was initiated in 12/17 pts. In all 12 pts, symptoms of palpitations were reproduced by initiated tachycardia: orthodromic reciprocating tachycardia (esophageal ventriculoatrial electrogram interval’ XOms) (5 pts), reentry within AV node (esophageal ventri-culoatrial electrogram interval < 55ms) (6 pts), atria1 flutter (I In 5/17 pts without induced tachycardia, 2/5 pt). continue with undocumented palpitations; palpitations ceased in 2/5; was subsequently documented
Transesophageal of
investigation permits ECG symptomatic
atria1
palpitations documentation pts.
ventricular in l/5.
pacing in
of
tachycardia
is
children, tachycardia
useful since
for it
in most
Jc:
AAP Program
and Abstracts
American
A NEW ANTITACHYCARDIA PACEMAKER WHICH DIFFERENTIATES SINUS FROM PAROXYSMAL TACHYCARDIA *Paul C. Gillette, M.D. and Alex Zinner, BME, South Carolina Children's Heart Center/Medical University of South Carolina 171 Ashley Avenue Charleston, SC 29425 Previous automatic antitachycardia pacemakers have frequently malfunctioned because their only criteria for determining tachycardia was rate. We implanted a new automatic antitachycardia pacemaker (Intertach) in 3 patients aged 11-19 years postoperative for transposition of the great arteries (2) or atria1 septal defect (1). Each patient had both brady and tachydysrhythmias. Each tachydysrhythmia was atria1 flutter. The pulse generators were implanted using transvenous subclavian puncture technique using a new screw-in bipolar lead. The pulse generators were implanted under the pectoralis muscle. Two of three pacemakers have successfully overdriven several hundred episodes of tachycardia in the 2-3 month follow-up. Each pacemaker has been tested against sinus tachycardia during treadmill testing. Using only rate as a criteria each pacemaker recognized sinus tachycardia as tachycardia. Using rate and rate of change of rate each pacemaker correctly failed to recognize sinus tachycardia as tachycardia. This new automatic antitachycardia pacemaker appears to be able to successfully treat atria1 flutter in pediatric postoperative patients.
PRIMARY ATRIAL TACHYCARDIAS IN CHILDHOOD: RESULTS OF CARDIAC AND SKELETAL MUSCLE BIOPSIES. Ann Dunn&an, M.D., FAAP*; Nancy A. Staley, M.D.; Stephen.A. Smith, M.D.; Mary Ella Pierpont, M.D., Ph.D.; Dianne Judd, David G. Benditt, M.D.; D. Woodrow Benson, Jr., M.D., Ph.D., FAAP. University of Minnesota, Minneapolis, MN We'evaluated
cardiac
(CM)
and
skeletal
muscle
histology in 10 patients (pts), age I to 1X years, with catheterization documented reentry (5 pts) or automatic (5 pts) atria1 tachycardia (primarv atria1 tachycardias). Symptoms included: syncope .(4 pts), palpitations (2 ptsl, heart failure (2 pts), none (2 pts). Light and electron microscopy was performed on ventricular (6 pts) and SM biopsies (10 pts). Serum and SM concentrations of free and acylcarnitine were determined. CM histology was abnormal in all 6 pts examined, and included fibrosis (5 pts); increased lipid (2 pts) (SM)
and
intercalated
discs
(2
pts);
dilated
sarcoplasmic
reticulum (2 pts); dilated mitochondria, myofilament loss, increased glycogen (I pt each). SM histology was abnormal in all pts with increased lipid (7 ots). endomysial fibrosis (4 pts), type I and type II fiber hypotrophy (1 pt each). Serum free and acylcarnitine concentrations were normal in all 10 ots. but SM loneu chain acylcarnitine was low in 7/10 and elevated in l/IO pt. SM short chain acylcarnitine concentration was reduced in l/IO pt. Thus in our pts with primary atria1 tachycardias, CM and SM histologic and carnitine abnormalities were common, suggesting that in otherwise healthy young people, primary atria1 tachycardias may be associated with skeletal and cardiac (i.e., generalized) muscle disease. .
I
Heart
ELECTROPHYSIOLOGIC FEATURES OF NEONATAL PAROXYSMAL ATRIAL TACHYCARDIA RESULTING IN PREVS POSTNATAL HEART FAILURE. Vincent R. Zales, MD*, Athi Narayan, MD, FAAP, Ann Dunnigan, MD, FAAP, D. Woodrow Benson, Jr., MD, PhD, FAAP, Department of Pediatrics, University of Minnesota, Minneapolis, MN the electrophysiologic features of atria1 tachycardia (PAT) in 12 neonates I-14 days) with hydrops fetalis (Pre-CHF) and compared them to 12 NB (age 2-34 days) with postnatal congestive heart failure (Post-CHF). No NB had structural heart disease. All had left ventricular dysfunction. In Pre-CHF NB, PAT was detected at 2X to 35 We
evaluated
paroxysmal (NB) (age
weeks (mean=31) gestation in 7 NB, at delivery in 3 NB, but not until 7 and 14 days postnatally in 2 NB. Spontaneous PAT onset and termination was observed in all Pre-CHF NB. However, in Post-CHF
NB,
a single, Drolonaed PAT During -sinus rhythum, 4/12 Post-CHF NB had evidence of tlon. Durmg postnatal PAT
episode was observed. Pre-CHF NB and 5/12 ventricular oreexcitaevaluation, ‘QRS was normal and the R-P or V-A Interval (from surface or esophageal ECG) was > 80 ms (p NS for Pre-CHF vs Post-CHF NB). However, PAT cycle length (mean?SD) was different for Pre-CHF NB (243i30 ms) vs. Post-CHF NB (208? 19 ms) (p < 0.05). Multiple recurrences and spontaneous terminations of PAT were observed in 12/12 Pre-CHF NB and in no Post-CHF NB. NB with hydrops develop symptoms from multiple PAT recurrences at relatively long cycle length (slow heart rate), whereas Post-CHF NB develop symptoms from sustained PAT at short cycle length (fast heart rate).
TRANSESOPHAGEAL ATRIAL PACING FOR EVALUATION OF PALPITATIONS IN CHILDREN. Ann Dunnigan, M.D., FAAP*; Edward D. Overholt, M.D.; Vincent R. Zales, M.D.; D. Woodrow Benson, Jr., M.D., Ph.D., FAAP. Department of Pediatrics. University of Minnesota, Minneapolis, MN. We evaluated the usefulness of transesophageal atria1 pacing to investigate the etiology - of palpitations in 17 patients (pts) age 5 to 16 vears (mean=9.7) who had had more than 2 episodes of palpitations. All pts had normal sinus rhythm ECGs, and no pt had symptoms during 24-48 hour ambulatory ECG (13 pts) or treadmill ECG (4 ptsl. In an effort to initiate tachycardia, trans-
esophageal atria1 pacing was performed with a bipolar electrode catheter and stimuli of 9.9 ms and IO-20mA using the following atria1 stimulation protocol: extrastimuli in sinus rhythm; refractory periods at 2 train cycle lengths; incremental pacing; bursts of rapid pacing. Isoproterenol (0.01 to 0.1 mcg/kg/min) and atropine (0.04 mg/kg) were administered, and the pacing protocol repeated. During study, tachycardia was initiated in 12/17 pts. In all 12 pts, symptoms of palpitations were reproduced by initiated tachycardia: orthodromic reciprocating tachycardia (esophageal ventriculoatrial electrogram interval’ XOms) (5 pts), reentry within AV node (esophageal ventri-culoatrial electrogram interval < 55ms) (6 pts), atria1 flutter (I In 5/17 pts without induced tachycardia, 2/5 pt). continue with undocumented palpitations; palpitations ceased in 2/5; was subsequently documented
Transesophageal of
investigation permits ECG symptomatic
atria1
palpitations documentation pts.
ventricular in l/5.
pacing in
of
tachycardia
is
children, tachycardia
useful since
for it
in most
Jc: