Sun Y, Blom NA, Yu Y, Ma P, Wang Y, Han X, Swenne CA, van der Wall EE.
The influence of premature ventricular contractions on left ventricular function in asymptomatic children without structural heart disease: an echocardiographic evaluation.
Int J Cardiovasc Imaging. 2003 Aug;19(4):295-9. doi: 10.1023/a:1025418531853.
Abstract/Text
BACKGROUND: Isolated monomorphic premature ventricular contractions (PVCs) are not uncommon in the pediatric population. The degree of cardiac dysfunction caused by PVCs in children without structural heart disease is unknown.
PURPOSE: To investigate the influence of PVCs on echocardiographic left ventricular (LV) systolic function in children without structural heart disease.
METHODS: Forty asymptomatic children with isolated monomorphic PVCs without structural heart disease were selected. The median age was 6 years, range of 3-12 years. The following subgroups were compared: frequent vs. infrequent PVCs (> or < or = 10/min); short vs. long coupling interval (RR'/RR ratio < or = or > 0.6); and short vs. long QT interval (QT < or = or > 400 ms). Using echocardiography the left ventricular ejection fraction (LVEF in percentage) and cardiac index (CI in L/min/m2) were measured for both normal sinus beats (SB-LVEF and CI), PVCs (PVC-LVEF and CI) and the average LVEF and CI were calculated. All values were expressed as means +/- SD.
RESULTS: In all children LV dimensions and the SB-LVEF and CI were within normal limits. The PVC-LVEF (48 +/- 5) and PVC-CI (1.57 +/- 0.19) were significantly decreased and the average CI was 2.41 +/- 0.29. In 27 pts with > 10 PVCs/min the average LVEF and CI decreased to 53 +/- 5 and 2.08 +/- 0.24 respectively. In 16 pts with PVCs and a short coupling interval (RR'/RR < or = 0.6) the PVC-LVEF and PVC-CI was 43 +/- 0.03 and 1.50 +/- 0.14, which was significantly lower than in 24 pts with a long coupling interval (58 +/- 4, 1.88 +/- 0.11). In 11 pts with a prolonged QT interval (> 400 ms) the PVC-LVEF and PVC-CI was significantly lower than in the 29 children with a shorter QT interval, 41 +/- 5 vs. 55 +/- 4 and 1.46 +/- 0.13 vs. 1.86 +/- 0.15 respectively (all p < 0.01).
CONCLUSION: In asymptomatic children with isolated monomorphic PVCs the average ejection fraction and cardiac output is markedly reduced if PVCs are frequent (> 10/min), have a short coupling interval or a prolonged QT interval.
Spector ZZ, Seslar SP.
Premature ventricular contraction-induced cardiomyopathy in children.
Cardiol Young. 2016 Apr;26(4):711-7. doi: 10.1017/S1047951115001110. Epub 2015 Jun 17.
Abstract/Text
BACKGROUND: Adults with high premature ventricular contraction burden can develop left ventricular dilation, dysfunction, and strain, consistent with a cardiomyopathy, which is reversible with radiofrequency ablation of the premature ventricular contractions. Evidence in children with similar ectopy burden is limited. We performed a single-centre retrospective review to examine the prevalence of premature ventricular contraction-induced cardiomyopathy, natural history of ventricular ectopy, and progression to ventricular tachycardia in children with frequent premature ventricular contractions.
METHODS: Children aged between 6 months and 18 years, with premature ventricular contractions comprising at least 20% of rhythm on 24-hour Holter monitor, were included in our study. Those with significant structural heart disease, ventricular tachycardia greater than 1% of rhythm at the time of premature ventricular contraction diagnosis, or family history of cardiomyopathy - except tachycardia-induced - were excluded. Cardiomyopathy was defined by echocardiographic assessment.
RESULTS: A total of 36 children met the study criteria; seven patients (19.4%, 95% CI 6.2-32.6%) met the criteria for cardiomyopathy, mostly at initial presentation. Ectopy decreased to <10% of beats without intervention in 16.7% (95% CI 4.3-29.1%) of the patients. No patient progressed to having ventricular tachycardia as more than 1% of beats on follow-up Holter. Radiofrequency ablation was performed in three patients without cardiomyopathy.
CONCLUSIONS: Our study demonstrates a higher prevalence of cardiomyopathy among children with high premature ventricular contraction burden than that previously shown. Ectopy tended to persist throughout follow-up. These trends suggest the need for a multi-centre study on frequent premature ventricular contractions in children. In the interim, regular follow-up with imaging to evaluate for cardiomyopathy is warranted.
Schwartz PJ, Stramba-Badiale M, Segantini A, Austoni P, Bosi G, Giorgetti R, Grancini F, Marni ED, Perticone F, Rosti D, Salice P.
Prolongation of the QT interval and the sudden infant death syndrome.
N Engl J Med. 1998 Jun 11;338(24):1709-14. doi: 10.1056/NEJM199806113382401.
Abstract/Text
BACKGROUND: The sudden infant death syndrome (SIDS) is multifactorial in origin, but its causes remain unknown. We previously proposed that prolongation of the QT interval on the electrocardiogram, possibly resulting from a developmental abnormality in cardiac sympathetic innervation, may increase the risk of life-threatening ventricular arrhythmias and contribute to this devastating disorder. We prospectively tested this hypothesis.
METHODS: Between 1976 and 1994, we recorded electrocardiograms on the third or fourth day of life in 34,442 newborns and followed them prospectively for one year. The QT interval was analyzed with and without correction for the heart rate.
RESULTS: One-year follow-up data were available for 33,034 of the infants. There were 34 deaths, of which 24 were due to SIDS. The infants who died of SIDS had a longer corrected QT interval (QTc) than did the survivors (mean [+/-SD], 435+/-45 vs. 400+/-20 msec, P<0.01) and the infants who died from causes other than SIDS (393+/-24 msec, P<0.05). Moreover, 12 of the 24 SIDS victims but none of the other infants had a prolonged QTc (defined as a QTc greater than 440 msec). When the absolute QT interval was determined for similar cardiac-cycle lengths, it was found that 12 of the 24 infants who died of SIDS had a QT value exceeding the 97.5th percentile for the study group as a whole. The odds ratio for SIDS in infants with a prolonged QTc was 41.3 (95 percent confidence interval, 17.3 to 98.4).
CONCLUSIONS: Prolongation of the QT interval in the first week of life is strongly associated with SIDS. Neonatal electrocardiographic screening may permit the early identification of a substantial percentage of infants at risk for SIDS, and the institution of preventive measures may therefore be possible.
Arnestad M, Crotti L, Rognum TO, Insolia R, Pedrazzini M, Ferrandi C, Vege A, Wang DW, Rhodes TE, George AL Jr, Schwartz PJ.
Prevalence of long-QT syndrome gene variants in sudden infant death syndrome.
Circulation. 2007 Jan 23;115(3):361-7. doi: 10.1161/CIRCULATIONAHA.106.658021. Epub 2007 Jan 8.
Abstract/Text
BACKGROUND: The hypothesis that some cases of sudden infant death syndrome (SIDS) could be caused by long-QT syndrome (LQTS) has been supported by molecular studies. However, there are inadequate data regarding the true prevalence of mutations in arrhythmia-susceptibility genes among SIDS cases. Given the importance and potential implications of these observations, we performed a study to more accurately quantify the contribution to SIDS of LQTS gene mutations and rare variants.
METHODS AND RESULTS: Molecular screening of 7 genes (KCNQ1, KCNH2, SCN5A, KCNE1, KCNE2, KCNJ2, CAV3) associated with LQTS was performed with denaturing high-performance liquid chromatography and nucleotide sequencing of genomic DNA from 201 cases diagnosed as SIDS according to the Nordic Criteria, and from 182 infant and adult controls. All SIDS and control cases originated from the same regions in Norway. Genetic analysis was blinded to diagnosis. Mutations and rare variants were found in 26 of 201 cases (12.9%). On the basis of their functional effect, however, we considered 8 mutations and 7 rare variants found in 19 of 201 cases as likely contributors to sudden death (9.5%; 95% CI, 5.8 to 14.4%).
CONCLUSIONS: We demonstrated that 9.5% of cases diagnosed as SIDS carry functionally significant genetic variants in LQTS genes. The present study demonstrates that sudden arrhythmic death is an important contributor to SIDS. As these variants likely modify ventricular repolarization and QT interval duration, our results support the debated concept that an ECG would probably identify most infants at risk for sudden death due to LQTS either in infancy or later on in life.
Otagiri T, Kijima K, Osawa M, Ishii K, Makita N, Matoba R, Umetsu K, Hayasaka K.
Cardiac ion channel gene mutations in sudden infant death syndrome.
Pediatr Res. 2008 Nov;64(5):482-7. doi: 10.1203/PDR.0b013e3181841eca.
Abstract/Text
Sudden infant death syndrome (SIDS) is multifactorial and may result from the interaction of a number of environmental, genetic, and developmental factors. We studied three major genes causing long QT syndrome in 42 Japanese SIDS victims and found five mutations, KCNQ1-K598R, KCNH2-T895M, SCN5A-F532C, SCN5A-G1084S, and SCN5A-F1705S, in four cases; one case had both KCNH2-T895M and SCN5A-G1084S. All mutations were novel except for SCN5A-F532C, which was previously detected in an arrhythmic patient. Heterologous expression study revealed significant changes in channel properties of KCNH2-T895M, SCN5A-G1084S, and SCN5A-F1705S, but did not in KCNQ1-K598R and SCN5A-F532C. Our data suggests that nearly 10% of SIDS victims in Japan have mutations of the cardiac ion channel genes similar to in other countries.
高岡秀幸：循環器症候群その他の循環器疾患を含めて III IX. 心筋疾患頻拍誘発心筋症：日本臨床.
Lishmanov A, Chockalingam P, Senthilkumar A, Chockalingam A.
Tachycardia-induced cardiomyopathy: evaluation and therapeutic options.
Congest Heart Fail. 2010 May-Jun;16(3):122-6. doi: 10.1111/j.1751-7133.2010.00147.x.
Abstract/Text
Tachycardia-induced cardiomyopathy is caused by sustained rapid ventricular rates and is one of the well-known forms of reversible myocardial dysfunction. The diagnosis is usually made retrospectively after marked improvement in systolic function is noted following control of the heart rate. Physicians should be aware that patients with seemingly idiopathic systolic dysfunction may have tachycardia-induced cardiomyopathy and that controlling the heart rate may result in improvement or even complete restoration of systolic function.
(c) 2010 Wiley Periodicals, Inc.
Fenelon G, Wijns W, Andries E, Brugada P.
Tachycardiomyopathy: mechanisms and clinical implications.
Pacing Clin Electrophysiol. 1996 Jan;19(1):95-106. doi: 10.1111/j.1540-8159.1996.tb04796.x.
Abstract/Text
Moore JP, Patel PA, Shannon KM, Albers EL, Salerno JC, Stein MA, Stephenson EA, Mohan S, Shah MJ, Asakai H, Pflaumer A, Czosek RJ, Everitt MD, Garnreiter JM, McCanta AC, Papez AL, Escudero C, Sanatani S, Cain NB, Kannankeril PJ, Bratincsak A, Mandapati R, Silva JN, Knecht KR, Balaji S.
Predictors of myocardial recovery in pediatric tachycardia-induced cardiomyopathy.
Heart Rhythm. 2014 Jul;11(7):1163-9. doi: 10.1016/j.hrthm.2014.04.023. Epub 2014 Apr 19.
Abstract/Text
BACKGROUND: Tachycardia-induced cardiomyopathy (TIC) carries significant risk of morbidity and mortality, although full recovery is possible. Little is known about the myocardial recovery pattern.
OBJECTIVE: The purpose of this study was to determine the time course and predictors of myocardial recovery in pediatric TIC.
METHODS: An international multicenter study of pediatric TIC was conducted. Children ≤18 years with incessant tachyarrhythmia, cardiac dysfunction (left ventricular ejection fraction [LVEF] <50%), and left ventricular (LV) dilation (left ventricular end-diastolic dimension [LVEDD] z-score ≥2) were included. Children with congenital heart disease or suspected primary cardiomyopathy were excluded. Primary end-points were time to LV systolic functional recovery (LVEF ≥55%) and normal LV size (LVEDD z-score <2).
RESULTS: Eighty-one children from 17 centers met inclusion criteria: median age 4.0 years (range 0.0-17.5 years) and baseline LVEF 28% (interquartile range 19-39). The most common arrhythmias were ectopic atrial tachycardia (59%), permanent junctional reciprocating tachycardia (23%), and ventricular tachycardia (7%). Thirteen required extracorporeal membrane oxygenation (n = 11) or ventricular assist device (n = 2) support. Median time to recovery was 51 days for LVEF and 71 days for LVEDD. Two (4%) underwent heart transplantation, and 1 died (1%). Multivariate predictors of LV systolic functional recovery were age (hazard ratio [HR] 0.61, P = .040), standardized tachycardia rate (HR 1.16, P = .015), mechanical circulatory support (HR 2.61, P = .044), and LVEF (HR 1.33 per 10% increase, p=0.005). For normalization of LV size, only baseline LVEDD (HR 0.86, P = .008) was predictive.
CONCLUSION: Pediatric TIC resolves in a predictable fashion. Factors associated with faster recovery include younger age, higher presenting heart rate, use of mechanical circulatory support, and higher LVEF, whereas only smaller baseline LV size predicts reverse remodeling. This knowledge may be useful for clinical evaluation and follow-up of affected children.
Published by Elsevier Inc.
Perry JC, Garson A Jr.
Supraventricular tachycardia due to Wolff-Parkinson-White syndrome in children: early disappearance and late recurrence.
J Am Coll Cardiol. 1990 Nov;16(5):1215-20. doi: 10.1016/0735-1097(90)90555-4.
Abstract/Text
UNLABELLED: The clinical course of 140 patients with Wolff-Parkinson-White syndrome who had their initial episode of supraventricular tachycardia before 18 years of age was reviewed. Among those whose tachycardia began at age 0 to 2 months, it disappeared in 93% and persisted in 7%. In 31%, it disappeared and reappeared at an average age of 8 years. Among patients whose tachycardia was present after age 5 years, it was persistent in 78% at a mean follow-up period of 7 years. Accessory connection location was mapped by electrophysiologic study in 87 patients and estimated by electrocardiography in 53 patients. There were no differences in tachycardia onset or recurrence based on accessory connection location. Congenital heart defects were present in 37% of all patients, 23% of whom had Ebstein's anomaly. Among all patients who underwent cardiac catheterization, 63% of those with a congenital heart defect had a rightsided accessory connection, whereas 61% of patients with a normal heart had a left-sided connection (p less than 0.01). Multiple accessory connections were found in 12% of patients with a congenital heart defect compared with 6% of those without such a defect.
IN CONCLUSION: 1) supraventricular tachycardia due to Wolff-Parkinson-White syndrome that begins in infancy may disappear, but it frequently recurs in later childhood; 2) if tachycardia is present after age 5 years, it persists in greater than 75% of patients; and 3) the location of the accessory connection does not affect the clinical course of tachycardia in children with Wolff-Parkinson-White syndrome.
Friedman RA, Walsh EP, Silka MJ, Calkins H, Stevenson WG, Rhodes LA, Deal BJ, Wolff GS, Demaso DR, Hanisch D, Van Hare GF.
NASPE Expert Consensus Conference: Radiofrequency catheter ablation in children with and without congenital heart disease. Report of the writing committee. North American Society of Pacing and Electrophysiology.
Pacing Clin Electrophysiol. 2002 Jun;25(6):1000-17. doi: 10.1046/j.1460-9592.2002.01000.x.
Abstract/Text
Pediatric and Congenital Electrophysiology Society (PACES); Heart Rhythm Society (HRS); American College of Cardiology Foundation (ACCF); American Heart Association (AHA); American Academy of Pediatrics (AAP); Canadian Heart Rhythm Society (CHRS); Cohen MI, Triedman JK, Cannon BC, Davis AM, Drago F, Janousek J, Klein GJ, Law IH, Morady FJ, Paul T, Perry JC, Sanatani S, Tanel RE.
PACES/HRS expert consensus statement on the management of the asymptomatic young patient with a Wolff-Parkinson-White (WPW, ventricular preexcitation) electrocardiographic pattern: developed in partnership between the Pediatric and Congenital Electrophysiology Society (PACES) and the Heart Rhythm Society (HRS). Endorsed by the governing bodies of PACES, HRS, the American College of Cardiology Foundation (ACCF), the American Heart Association (AHA), the American Academy of Pediatrics (AAP), and the Canadian Heart Rhythm Society (CHRS).
Heart Rhythm. 2012 Jun;9(6):1006-24. doi: 10.1016/j.hrthm.2012.03.050. Epub 2012 May 10.
Abstract/Text
Kurosaki K, Miyazaki A, Watanabe K, Echigo S.
Long-term outcome of isolated congenital complete atrioventricular block pacing since neonatal period: experience at a single Japanese institution.
Circ J. 2008 Jan;72(1):81-7. doi: 10.1253/circj.72.81.
Abstract/Text
BACKGROUND: Few investigators have examined the outcome of patients with isolated congenital complete atrioventricular block (CCAVB) paced from the neonatal period. The present study follows the clinical course and describes the outcome of patients who have been paced with CCAVB since they were neonates.
METHODS AND RESULTS: The medical records of 20 patients with CCAVB paced as neonates between 1981 and 2006 were retrospectively studied and reviewed; 18 were diagnosed in utero and 2 at birth. SS-A antibodies were detected in 9 of 14 (64%) mothers tested. The median age at follow-up was 5.6 years (range, 2 days to 21.9 years). Three (15%) of the early neonates died and 3 (15%) died later: 2 from dilated cardiomyopathy (DCM) and 1 from pneumonia. The total mortality rate was 30%. The cumulative probability of survival at 10 years was 73%. Of the 14 survivors, 4 developed DCM, representing a total morbidity of 30%. The cumulative probability of freedom from DCM at 10 years was 59%.
CONCLUSIONS: Patients with CCAVB who undergo pacing as neonates have high mortality and high morbidity because of DCM. Left ventricular pacing or resynchronization can benefit patients who develop DCM and left ventricular epicardial pacing is recommended for neonates with CCAVB.
Shalganov TN, Paprika D, Vatasescu R, Kardos A, Mihalcz A, Kornyei L, Szatmari A, Szili-Torok T.
Mid-term echocardiographic follow up of left ventricular function with permanent right ventricular pacing in pediatric patients with and without structural heart disease.
Cardiovasc Ultrasound. 2007 Mar 12;5:13. doi: 10.1186/1476-7120-5-13. Epub 2007 Mar 12.
Abstract/Text
BACKGROUND: Chronic right ventricular apical pacing may have detrimental effect on left ventricular function and may promote to heart failure in adult patients with left ventricular dysfunction.
METHODS: A group of 99 pediatric patients with previously implanted pacemaker was studied retrospectively. Forty-three patients (21 males) had isolated congenital complete or advanced atrioventricular block. The remaining 56 patients (34 males) had pacing indication in the presence of structural heart disease. Thirty-two of them (21 males) had isolated structural heart disease and the remaining 24 (13 males) had complex congenital heart disease. Patients were followed up for an average of 53 +/- 41.4 months with 12-lead electrocardiogram and transthoracic echocardiography. Left ventricular shortening fraction was used as a marker of ventricular function. QRS duration was assessed using leads V5 or II on standard 12-lead electrocardiogram.
RESULTS: Left ventricular shortening fraction did not change significantly after pacemaker implantation compared to preimplant values overall and in subgroups. In patients with complex congenital heart malformations shortening fraction decreased significantly during the follow up period. (0.45 +/- 0.07 vs 0.35 +/- 0.06, p = 0.015). The correlation between the change in left ventricular shortening fraction and the mean increase of paced QRS duration was not significant. Six patients developed dilated cardiomyopathy, which was diagnosed 2 months to 9 years after pacemaker implantation.
CONCLUSION: Chronic right ventricular pacing in pediatric patients with or without structural heart disease does not necessarily result in decline of left ventricular function. In patients with complex congenital heart malformations left ventricular shortening fraction shows significant decrease.
van Geldorp IE, Delhaas T, Gebauer RA, Frias P, Tomaske M, Friedberg MK, Tisma-Dupanovic S, Elders J, Früh A, Gabbarini F, Kubus P, Illikova V, Tsao S, Blank AC, Hiippala A, Sluysmans T, Karpawich P, Clur SA, Ganame X, Collins KK, Dann G, Thambo JB, Trigo C, Nagel B, Papagiannis J, Rackowitz A, Marek J, Nürnberg JH, Vanagt WY, Prinzen FW, Janousek J; Working Group for Cardiac Dysrhythmias and Electrophysiology of the Association for European Paediatric Cardiology.
Impact of the permanent ventricular pacing site on left ventricular function in children: a retrospective multicentre survey.
Heart. 2011 Dec;97(24):2051-5. doi: 10.1136/heartjnl-2011-300197. Epub 2011 Sep 14.
Abstract/Text
BACKGROUND: Chronic right ventricular (RV) pacing is associated with deleterious effects on cardiac function.
OBJECTIVE: In an observational multicentre study in children with isolated atrioventricular (AV) block receiving chronic ventricular pacing, the importance of the ventricular pacing site on left ventricular (LV) function was investigated.
METHODS: Demographics, maternal autoantibody status and echocardiographic measurements on LV end-diastolic and end-systolic dimensions and volumes at age <18 years were retrospectively collected from patients undergoing chronic ventricular pacing (>1 year) for isolated AV block. LV fractional shortening (LVFS) and, if possible LV ejection fraction (LVEF) were calculated. Linear regression analyses were adjusted for patient characteristics.
RESULTS: From 27 centres, 297 children were included, in whom pacing was applied at the RV epicardium (RVepi, n = 147), RV endocardium (RVendo, n = 113) or LV epicardium (LVepi, n = 37). LVFS was significantly affected by pacing site (p = 0.001), and not by maternal autoantibody status (p = 0.266). LVFS in LVepi (39 ± 5%) was significantly higher than in RVendo (33 ± 7%, p < 0.001) and RVepi (35 ± 8%, p = 0.001; no significant difference between RV-paced groups, p = 0.275). Subnormal LVFS (LVFS < 28%) was seen in 16/113 (14%) RVendo-paced and 21/147 (14%) RVepi-paced children, while LVFS was normal (LVFS ≥ 28%) in all LVepi-paced children (p = 0.049). These results are supported by the findings for LVEF (n = 122): LVEF was <50% in 17/69 (25%) RVendo- and in 10/35 (29%) RVepi-paced patients, while LVEF was ≥ 50% in 17/18 (94%) LVepi-paced patients.
CONCLUSION: In children with isolated AV block, permanent ventricular pacing site is an important determinant of LV function, with LVFS being significantly higher with LV pacing than with RV pacing.
