ABSTRACT
Abstract Background: Idiopathic ventricular tachycardia (VT) in children with structurally normal hearts is generally unrelated to the risk of sudden arrhythmic death. Still, it may be associated with deterioration in the quality of life. VT involving the fascicular conduction system is the most typical form of idiopathic left VT. In this retrospective study, we describe the experience of the clinical presentation, catheter ablation, and long-term follow-up of left fascicular VT in children. Methods: An electrophysiological study was performed on consecutive children at a single tertiary center. Clinical fascicular left VT was induced by programmed stimulation, and catheter ablation was guided searching for Purkinje potentials. Results: We included 18 patients (0.8 patients/year): 14 (77.8%) males and four females. The mean age of the first VT episode was 8.5 ± 5 years. Intravenous verapamil administration was effective for paroxysmal fascicular VT but not for prevention of recurrences. The mean age at the time of catheter ablation was 11.1 ± 3.8 years (8 months-16 years). The mean weight was 36.8 ± 16.4 kg (8.7-58 kg). A 100% success rate was observed with catheter ablation after repeated procedures without major complications. Mean follow-up was 2.0 ± 1.2 years (1.0-4.0 years, median 1.5), with permanent success in all patients and no antiarrhythmic drug administration. Conclusions: Fascicular VT has an adverse clinical course in children. In most cases, this condition is drug refractory. Catheter ablation is successful and safe treatment and should represent the first-line approach in symptomatic children.
Resumen Introducción: La taquicardia ventricular (TV) idiopática en niños con corazón estructuralmente normal generalmente no se relaciona con el riesgo de muerte súbita arrítmica, pero puede asociarse con deterioro de la calidad de vida. La TV que involucra el sistema de conducción fascicular es la forma más común de TV izquierda idiopática. En este estudio retrospectivo se describe la experiencia de presentación clínica, ablación con catéter y seguimiento a largo plazo de TV fascicular en niños. Métodos: Se llevó a cabo un estudio electrofisiológico en niños consecutivos en un centro terciario. La TV fascicular clínica se indujo mediante la estimulación programada y la ablación con catéter fue guiada buscando el registro de potenciales de Purkinje. Resultados: Se incluyeron 18 pacientes (0.8 pacientes/año): 14 (77.8%) de sexo masculino y cuatro de sexo femenino. La media de edad a la cual ocurrió el primer episodio fue de 8.5 ± 5 años. La administración intravenosa de verapamilo fue eficaz para la TV fascicular paroxística, pero no para prevención de recurrencias. La media de edad de la ablación con catéter fue de 11.1 ± 3.8 años (8 meses-16 años). La media del peso fue 36.8 ± 16.4 kg (8.7-58 kg). Se observó el 100% de éxito con la ablación con catéter después de procedimientos repetidos sin complicaciones mayores. La media de seguimiento fue de 2.0 ± 1.2 años (1.0-4.0, mediana de 1.5 años) con éxito permanente en todos los pacientes y sin administración de fármacos antiarrítmicos. Conclusiones: En niños, el curso clínico de la TV fascicular es adverso. Además, en la mayoría de los casos, esta condición es refractaria a fármacos. La ablación con catéter resulta exitosa y segura y debe representar el abordaje de primera línea en niños sintomáticos.
ABSTRACT
Double tachycardia is defined as the coexistence of supraventricular tachycardia (SVT) and ventricular tachycardia (VT). In clinical practice, incidentally encountered double tachycardia is difficult to diagnose during electrophysiology study without prior documentation of both tachycardias. SVT can be confused with VT because SVT sometimes show an aberrant conduction depending on heart rate. In the present case, a patient with Wolff-Parkinson-White syndrome exhibited atrioventricular reentrant tachycardia (AVRT) via a concealed bypass tract and idiopathic left ventricular tachycardia (ILVT), which were difficult to discriminate because of their similar cycle length and interrelationship.
Subject(s)
Humans , Electrophysiology , Heart Rate , Tachycardia , Tachycardia, Supraventricular , Tachycardia, Ventricular , Wolff-Parkinson-White SyndromeABSTRACT
Objective To analyze the clinical manifestations,diagnosis and treatment of idiopathic left ventricular tachycardia(ILVT)in infants and young children.Methods The clinical data,including manifestations,lab results and treatments of 37 cases of ILVT in infants and young children were analyzed retrospectively.Results ILVT were seen more in young children older than 1 year old and male infants.A total of 37 cases with ILVT showed diverse clinical manifestations,5 children had cardiac insufficiency with oliguria and edema,2 children had syncope.There were 8 children without any symptoms,and 22 children had some symptoms,which mainly included agitation and crying,weakness and sweaty,vomitting and pale com-plexion.Holter showed incessant ILVT in 20 cases(54.1%),and paroxysmal in 17 cases(45.9%).Of the 37 cases,9 cases presented tachycardia-induced cardiomyopathy(TIC),8 of them were secondary to the in-cessant ILVT.Children with TIC compared with those without TIC,the ventricular rate were faster[(206.2 ± 38.7)beats/min vs.(171.8 ±38.7)beats/min,P<0.05],the duration were longer[(22.6 ± 15.3)days vs. (9.8 ±6.0)days,P<0.05].A total of 34 cases were given by antiarrhythmic drugs,verapamil was higher effective in reversion to sinus rhythm.Radiofrequency ablations were conducted in 8 cases,resulting in ven-tricular tachycardia elimination.All of children were fine during following up periods.After successful control of tachycardia,left ventricular end-diastolic diameter and left ventricular ejection fraction in patients with TIC gradually recovered[(35.4 ± 7.2 )mm vs.(28.9 ± 5.6 )mm,P <0.05;(46.7 ± 4.0 )% vs.(70.1 ± 1 .5 )%,P<0.0 1 ] .Conclusion ILVT in infants and young children are rare,and present different manifes-tions.An incessant ILVT with faster ventricular rate and longer duration are more frequently complicated by TIC.Radiofrequency ablation is the effective way of radical cure of the disease.The diagnosis and treatment for the tachycardia are particularly important in early time,and the prognosis are good.
ABSTRACT
A 12-year-old girl with symptoms of fatigue, decreased exercise tolerance and progressive dyspnea (New York Heart Association functional class III) with a possible diagnosis of dilated cardiomyopathy secondary to viral myocarditis. Because of incessant wide QRS tachycardia refractory to antiarrhythmic drugs, she was referred for electrophysiological study. The diagnosis was idiopathic left ventricular tachycardia involving the posterior fascicle of the left bundle branch. After successful treatment with radiofrequency catheter ablation guided by a Purkinje potential radiological and echocardiographic evaluation showed complete reversal of left ventricular function in the first 3 months and no recurrence of arrhythmia during 2 years of follow up.
Niña de 12 años de edad con síntomas por fatiga, disminución de la tolerancia al ejercicio y disnea progresiva (clase funcional III de la New York Heart Association) con un posible diagnóstico de miocardiopatía dilatada secundaria a miocarditis viral. Debido a taquicardia con QRS ancho de comportamiento incesante refractaria a diversos fármacos antiarrítmicos fue referida para estudio electrofisiológico. El diagnóstico final fue taquicardia ventricular izquierda idiopática con participación del fascículo posterior de la rama izquierda. Después del tratamiento exitoso con ablación transcatéter con radiofrecuencia guiado por un potencial de Purkinje la evaluación radiológica y ecocardiográfica demostró reversión completa de la función ventricular izquierda en los primeros 3 meses y sin recurrencia de la arritmia durante 2 años de seguimiento.
Subject(s)
Child , Female , Humans , Cardiomyopathy, Dilated/etiology , Tachycardia, Ventricular/complicationsABSTRACT
PURPOSE: We hypothesized that Purkinje potential and their preferential conduction to the left ventricle (LV) posteroseptum during sinus rhythm (SR) are part of reentrant circuits of idiopathic left ventricular tachycardia (ILVT) and reentry anchors to papillary muscle. MATERIALS AND METHODS: In 14 patients with ILVT (11 men, mean age 31.5+/-11.1 years), we compared Purkinje potential and preferential conduction during SR with VT by non-contact mapping (NCM). If clear Purkinje potential(SR) was observed in the LV posteroseptum and the earliest activation site (EA) of preferential conduction at SR (EASR) was well matched with that of VT (EAVT), EASR was targeted for radiofrequency catheter ablation (RFCA). Also, the anatomical locations of successful ablation sites were evaluated by echocardiography in five additional patients. RESULTS: 1) All induced VTs exhibited clear Purkinje potential(VT) and preferential conduction in the LV posteroseptum. The Purkinje potential(VT) and EAVT was within 5.8+/-8.2 mm of EASR. However, the breakout sites of VT were separated by 30.2+/-12.6 mm from EAVT to the apical side. 2) Purkinje potential(SR) demonstrated a reversed polarity to Purkinje potential(VT), and the interval of Purkinje potential(SR)-QRS was longer than the interval of Purkinje potential(VT)-QRS (p<0.02) 3) RFCA targeting EASR eliminated VT in all patients without recurrence within 23.3+/-7.5 months, and the successful ablation site was discovered at the base of papillary muscle in the five additional (100%) patients. CONCLUSION: NCM-guided localization of EASR with Purkinje potential(SR) matches well with EAVT with Purkinje potential(VT) and provides an effective target for RFCA, potentially at the base of papillary muscle in patients with ILVT.
Subject(s)
Adult , Female , Humans , Male , Young Adult , Catheter Ablation , Electrophysiology , Purkinje Fibers/physiology , Tachycardia, Ventricular/physiopathology , Ventricular Dysfunction, Left/physiopathologyABSTRACT
ObjectiveTo observe the therapeutic effect of radiofrequency catheter ablation for idiopathic left ventricular tachycardia.To explore the relationship between surface electrocardiography and successful radiofrequency ablation location. MethodsThe electrophysiological data of surface electrocardiography and radiofrequency ablation,and the data of Holter in postorperation after 24 h and a half months,and tracking follow-up of 30 patients (23 males and 7 females)with idiopathic left ventricular tachycardia onset were retrospectively analyzed. ResultsRadiofrequency catheter ablation was successful in 29 patients(96.7%).The Holter was conducted in 29patients before and after the operation,the difference in average beats/24h before the operation(20 997 ± 10 786)and after the operation(921 ± 1 337)was statistically significant(P＜0.01).During the period of 1 to 3 months follow-up,2 patients relapsed and were all successfully re-ablated.No complication was found.The ventricular tachycardia lesions in left ventricular septum were found in 21 patients,of which 19 cases were located in a quadrant axis (-75.83 ± 19.36)°(-30 °～-90 °),and those in the left ventricular apex were in 9 cases,of which 7 cases were in the 2 quadrant axis(-102.6 ± 5.93)°(-91 °～-110 °). ConclusionRadiofrequency catheter ablation was an effeetive treatment technique for idiopathic left ventricular tachycardia with high successful rate,it could be selected as the first line treatment in patients with idiopathic left ventricular tachycardia.During idiopathic left ventricular tachycardia onset,the surface electrocardiography could help determine the initial site of ventricular tachycardia.
ABSTRACT
BACKGROUND: Unipolar electrogram was reported to be useful for localization of manifest accessory pathway conduction during surgical or transcatheter ablation. However, it is not clear whether the unipolar electrogram would also be useful for localizing the origin of idiopathic left ventricular tachycardia (ILVT) in which pace mapping, activation time and recording of Purkinje (P)-potential have been used for guiding the successful ablation. METHODS: In patients who underwent catheter ablation for ILVT, bipolar and unipolar electrograms were recorded at the sites of current delivery. We analysed the time from P-potential to QRS onset (P-QRS time), time from local ventricular electrogram to QRS onset (V-QRS time) and the morphology and slope of rapid downstroke of unipolar electrograms (Uni-slope) during induced ILVT both at successful and unsuccessful sites. RESULTS: In 14 consecutive patients (11M/3F, mean age 29.3) with ILVT and successful ablation, QRS morphology of ventricular tachycardia was of right bundle branch block (RBBB) with left axis deviation and right axis deviation in 11 and 3 patients, respectively. The average number of current delivery was 4.5 (range 2-12). P-potential was observed in 10/14 (71%) successful sites and 37/47 (79%) unsuccessful ablation sites. The morphology of unipolar electrogram was QS pattern in 12 and QrS pattern in 2 successful sites but rS pattern was not observed at successful sites. P-QRS time was 26.5+/-12.4 and 26.6+/-14.9 msec (p=ns), V-QRS time 3.9+/-7.7 and 0.2+/-8.9 msec (p=ns), Uni-slope 7.1+/-3.1 and 7.3+/-4.5 mV/10 msec (p=ns) at successful and unsuccessful sites, respectively, showing no significant differences between successful and unsuccessful sites. CONCLUSIONS: The slope of rapid downstroke in unipolar electrogram was not useful as a guide for localization of successful ablation in patients with ILVT. However, absence of initial 'r'wave in unipolar electrogram may be helpful in conjunction with other conventional criteria for successful ablation.
Subject(s)
Humans , Axis, Cervical Vertebra , Bundle-Branch Block , Catheter Ablation , Tachycardia, VentricularABSTRACT
BACKGROUND: Idiopathic left ventricular tachycardia (ILVT), one of common idiopathic ventricular tachycardias which develop without structural abnormality of the heart. It has been reported that ILVT has a typical QRS morphology of right bundle branch block and left axis and unique clinical and electrophysiological characteristics. Intravenous verapamil is shown to be very effective in acute termination. However, radio-frequency catheter ablation is now recommended as the treatment of choice for long-term managemnt. This study was performed to determine the clinical and electrophysiological characteristics of ILVT and to evaluate the effects of radiofrequency catheter ablation (RFCA) of ILVT. METHODS: Seventeen patients (12 men, 5 women:mean age : 39+/-15 years) with ILVT were included in this study. ILVT was diagnosed based on the results of electrocardiogram, echocardiogram, cardiac catheterization, and electrophysiology study (EPS). EPS was performed with the standard technique in fasting state for more than 6 hours. In patients with their clinical VTs reproducibly induced during EPS, RFCA was attempted using endocardial activation mapping and pace-mapping. The mode of induction and termination, response to verapamil, and site of origin of the ILVT were evaluated. The local electrogram chacteristics at the sites of successful catheter ablation were also evaluated in patients undergoing RFCA. RESULTS: All 17 patients presented with recurrent palpitation but none with syncope or sudden cardiac death. None had a significant heart disease. The spontaneous ventricular tachycardias were of right bundle branch block morphology with left superior axis in 11 cases, right inferior axis in 1, and northwest axis in 5. The VTs were terminated with intravenous verapamil in all of 14 patients receiving IV verapamil. VT of same morphology as the clinical VT was induced with programmed electrical stimulation in 13 cases (76.4%), of whom 2 cases required isoproterenol infusion. The most frequent mode of induction was single ventricular extrastimulation (7 cases). Mean cycle length of the induced VTs was 320+/-59 ms. RFCA was attempted in 11 cases and successful in 9 (82%). The successful ablation sites were and central mid septum (3 cases), posterior mid septum (3 cases), posterior apical septum (3 patients) of the left ventricle (3 patients). At the successful ablation sites, the local ventricular activation preceded the onset of QRS complex by 34+/-15 ms (range : 10-58) and the paced QRS complexes during pace-mapping were identical to those of the induced or spontaneous VTs in 11.7+/-0.4 leads (range : 11-12). However, Purkinje potential was recorded only in 2 cases. There were no complications associated with EPS and RFCA. CONCLUSIONS: The present study suggests that ILVT is mild in symptoms, highly sensitive to verapamil, mostly caused by reentry, and can be cured by radiofrequency catheter ablation guided by pace-mapping and activation mapping.
Subject(s)
Humans , Male , Axis, Cervical Vertebra , Bundle-Branch Block , Cardiac Catheterization , Cardiac Catheters , Catheter Ablation , Catheters , Death, Sudden, Cardiac , Electric Stimulation , Electrocardiography , Electrophysiology , Fasting , Heart , Heart Diseases , Heart Ventricles , Isoproterenol , Syncope , Tachycardia, Ventricular , VerapamilABSTRACT
BACKGROUND: Idiopathic left ventricular tachycardia (ILVT), one of common idiopathic ventricular tachycardias which develop without structural abnormality of the heart. It has been reported that ILVT has a typical QRS morphology of right bundle branch block and left axis and unique clinical and electrophysiological characteristics. Intravenous verapamil is shown to be very effective in acute termination. However, radio-frequency catheter ablation is now recommended as the treatment of choice for long-term managemnt. This study was performed to determine the clinical and electrophysiological characteristics of ILVT and to evaluate the effects of radiofrequency catheter ablation (RFCA) of ILVT. METHODS: Seventeen patients (12 men, 5 women:mean age : 39+/-15 years) with ILVT were included in this study. ILVT was diagnosed based on the results of electrocardiogram, echocardiogram, cardiac catheterization, and electrophysiology study (EPS). EPS was performed with the standard technique in fasting state for more than 6 hours. In patients with their clinical VTs reproducibly induced during EPS, RFCA was attempted using endocardial activation mapping and pace-mapping. The mode of induction and termination, response to verapamil, and site of origin of the ILVT were evaluated. The local electrogram chacteristics at the sites of successful catheter ablation were also evaluated in patients undergoing RFCA. RESULTS: All 17 patients presented with recurrent palpitation but none with syncope or sudden cardiac death. None had a significant heart disease. The spontaneous ventricular tachycardias were of right bundle branch block morphology with left superior axis in 11 cases, right inferior axis in 1, and northwest axis in 5. The VTs were terminated with intravenous verapamil in all of 14 patients receiving IV verapamil. VT of same morphology as the clinical VT was induced with programmed electrical stimulation in 13 cases (76.4%), of whom 2 cases required isoproterenol infusion. The most frequent mode of induction was single ventricular extrastimulation (7 cases). Mean cycle length of the induced VTs was 320+/-59 ms. RFCA was attempted in 11 cases and successful in 9 (82%). The successful ablation sites were and central mid septum (3 cases), posterior mid septum (3 cases), posterior apical septum (3 patients) of the left ventricle (3 patients). At the successful ablation sites, the local ventricular activation preceded the onset of QRS complex by 34+/-15 ms (range : 10-58) and the paced QRS complexes during pace-mapping were identical to those of the induced or spontaneous VTs in 11.7+/-0.4 leads (range : 11-12). However, Purkinje potential was recorded only in 2 cases. There were no complications associated with EPS and RFCA. CONCLUSIONS: The present study suggests that ILVT is mild in symptoms, highly sensitive to verapamil, mostly caused by reentry, and can be cured by radiofrequency catheter ablation guided by pace-mapping and activation mapping.
Subject(s)
Humans , Male , Axis, Cervical Vertebra , Bundle-Branch Block , Cardiac Catheterization , Cardiac Catheters , Catheter Ablation , Catheters , Death, Sudden, Cardiac , Electric Stimulation , Electrocardiography , Electrophysiology , Fasting , Heart , Heart Diseases , Heart Ventricles , Isoproterenol , Syncope , Tachycardia, Ventricular , VerapamilABSTRACT
BACKGROUND: Idiopathic left ventricular tachycardia(ILVT) with no structural heart disease is not an uncommon disease and characterized by the ECG feature of right bundle branch block. This study was performed to evaluate the effectiveness of radiofrequency catheter ablation (RFCA) for the treatment of ILVT and the usefulness of Purkinje potential(P-potential) in determining the site of successful ablation and to compare the biophysical parameter according to the modes of energy application. METHOD: From January 1993 to July 1996, 18 patients with symptomatic ILVT underwent RFCA. The ablation site were guided by pace mapping, ventricular activation mapping or P-potential. RESULTS: Of the 18 patients, there were 14 male and 4 female patients with a mean age of 34.1 years-old. RFCA eliminated VT successfully in 14 of total 18 patients(78%), 11 of 12 in leftaxis VT, 2 of 3 in right axis VT and 1 of 3 in northwest axis VT. Successful sites of wall in 3 patients with right axis deviation or northwest axis. Ablations in 5 of the 9 patients, guided by pace mapping or ventricular activation mapping, were successful and in 9 all patients, guided by P-potential, were successful. In 9 patients guided by the P-potential, the earliest P-potential appeared 22.7+/-7.7msec earlier than the QRS complex during sinus rhythm and 32.0+/-11.5msec earlier during VT. Pace mapping with similar QRS was not necessarily essential for a successful ablation. In comparing the biophysical parameters according to energy delivery modes, more energy was delivered safety during successful ablation in temperature mode(mean 1148.3J) than constant power mode(520.9J). No acute and late complication was developed during ablation and for a mean of 25 months follow-up. One case of VT with right axis deviation relapsed 2 months after successful ablation. CONCLUSION: RFCA is useful for the effective and safe treatment of ILVT. The earliest P-potential might be a better guide than mapping or earliest ventriclar activation for the determination of ablation sites in ILVT with left axis deviation. More energy was delivered safety during successful ablation in temperature mode than constant power mode.
Subject(s)
Female , Humans , Male , Axis, Cervical Vertebra , Bundle-Branch Block , Catheter Ablation , Electrocardiography , Follow-Up Studies , Heart Diseases , Tachycardia, VentricularABSTRACT
BACKGROUND: Idiopathic left ventricular tachycardia with a QRS pattern of right bundle branch block and left axis deviation that is sensitive to verapamil is electrophysiologically distinct arrhythmia entity but descriptions in pediatric ages are infrequent. This study attempted to describe the clinical presentation and dignostic clues from the surface ECG in children with idiopathic left venteicular tachycardia. METHODS: We retrospectively reviewed the medical records, electrocardiograms, Holter recordings, echocardiographic reports of 10 children with idiopathic left ventricular tachycardia who have been managed at Sejong General Hospital and Asan Medical Center, Seoul, Korea from January 1991 to July 1996. Follow-up periods are 2 months to 5 years(mean=26 months). RESULTS: 1) Age of tachycardia onset was 8 months to 14 years(median=4.3 years). In 3 children tachycardia began from infancy. The main complaint in older children was palpitation and chest discomfort but young childen complained abdominal pain during tachycardia attack. Tachycardia was paroxysmal and sustained. Tachycardia responded to intravenous use of verapamil in 9 patients and was controlled by chronic verapamil medication in 6 patients. 2 patients were well without medication. Radiofrequency catheter ablation was done in an adolescent patient successfully. 2) In sinus rhythm, surface ECG showed normal QRS axis and normal QRS morphologies in all patients. During ventricular tachycardia, the heart rate was 183 to 270 beats/min. The taxhycardia of RBBB morphology was observed in all patients. The mean QRS duration was 109+-12ms and the QRS axis was -50* to -90*. Themean RS interval was 60+-12ms. AVdissociation was found on surface RCG in all patients and confirmed in 4 patients by transesophageal ECG. We tried rapid transesophageal atrial pacing in 3 patients and could induce and terminate the ventricular tachycardia. CONCLUSIONS: Idiopathic left ventricular tachycaedia is rare in childhood and is seen from infancy. Idiopathic left ventricular tachycardia is generally benign but occasionally causesmyocardial dysfunction. Idiopathic ventricular tachycardia with a QRS pattern of right bundle branch block amd left axis deviation that is sensitive to verapamil in children should not be confused with supraventricular tachycardia with aberrancy and most helpful diagnostic clue is AV dissociation in surface ECG.