ABSTRACT
Objective:To explore the safety and efficacy of Propafenone in terminating paroxysmal supraventricular tachycardia (PSVT) in children and analyze the factors influencing the effectiveness.Methods:A retrospective study was conducted on 169 PSVT children treated with Propafenone in the Department of Pediatric Cardiology, Heart Center, the First Hospital of Tsinghua University from September 2014 to October 2021.There were 118 boys and 51 girls with an average age of (2.84±2.91) years (age range: 14 days-13 years). According to age, they were divided into ≤ 1-year-old group, >1-3-year-old group, >3-7-year-old group, and >7-year-old group.Mea-surement data were compared between groups using t-test and Mann- Whitney U test.Counting data were analyzed by χ2 test. Results:Among the 169 children with PSVT, 65 cases (38.5%) were below 1 year old, 47 cases (27.8%) were >1-3 years old, 40 cases (23.7%) were >3-7 years old, 17 cases (10.1%) were above 7 years old.About 24 cases (14.2%) were combined with congenital heart disease.A total of 153 cases (90.5%) had nonspecific symptoms at the first visit.A total of 4.1% (7/169 cases) were complicated with tachycardia-induced cardiomyopathy, and their left ventricular ejection fraction increased from (44.0±4.0)% to (53.7±6.9)% after successful control of PSVT ( t=-4.700, P=0.003). The complete termination of PSVT by intravenous Propafenone was achieved in 125 of 169 cases (74.0%, 125/169 cases). The complete termination rate after multiple times of administration (74.0%) was significantly higher than that after the first intravenous injection (53.3%, 90/169 cases) ( χ2=15.657, P<0.001). There was a significant difference regarding the complete termination rate between children ≤1 year old (60.0%, 39/65 cases) and those >1 year old (82.7%, 86/104 cases) ( χ2=10.696, P=0.001). For children ≤1 year old, 1.5 mg/kg Propafenone (51.1%, 23/45 cases) showed better efficacy for PSVT termination than 1.0 mg/kg Propafenone (20.0%, 4/20 cases) ( χ2=5.519, P=0.019). For children >1 year old, there was no significant diffe-rence between 1.5 mg/kg and 1.0 mg/kg Propafenone groups (57.9% vs.62.1%) ( χ2=0.180, P=0.671). The adverse reaction rate of intravenous Propafenone was 9.5% (16/169 cases). One case presented with severe hypotension, which occurred in a child with right cardiac insufficiency with tricuspid valve depression; 15 cases showed abnormal cardiac conduction and recovered spontaneously in a short time.There was no deterioration of cardiac function in children with mildly to moderately reduced cardiac function. Conclusions:It is relatively safe and effective to terminate PSVT in children with intravenous Propafenone.The complete termination rate is 74.0%, which is related to age, dose and times of administration.Despite of low incidence of side effects, Propafenone should not be used to treat PSVT with cardiac function which is significantly impaired or unclear secondary to persistent tachycardia.Special attention should be paid to cardiac function deterioration in these patients.
ABSTRACT
Objective:To investigate clinical electrophysiological characteristics of idiopathic ventricular arrhythmias (VAs) and outcomes of radiofrequency catheter ablation (RFCA) in pediatric patients.Methods:A total of 328 consecutive pediatric patients with VAs and treated with RFCA in the First Hospital of Tsinghua University from January 2014 to December 2019 were recruited, involving 205 males and 123 females with the mean age of (7.8±3.9) years and the mean body weight of (32.8±17.7) kg.Their clinical electrophysiological characteristics, RFCA outcomes of different origins of VAs and complications were analyzed.Results:Among the 328 patients with the mean onset age of (5.4±4.1) years, 57.6% had frequent premature ventricular complex (PVC), 28.7% had paroxysmal ventricular tachycardia (VT) and 13.7% had incessant VT.A total of 38/328 cases (11.6%) VAs children were complicated with tachycardia-induced cardiomyopathy.Except for 13 cases of non-induced VAs, among 315 cases there were 152/328 cases (46.4%) originated from the ventricular outflow tract (including 46.1% of the origination of the right ventricular outflow tract septum, 27.6% of the origination of the left coronary cusp, 18.4% of the origination of the right coronary cusp, and 7.9% of the origination of the right ventricular outflow tract free wall), 55/328 cases (16.5%) originated from the tricuspid valve, 54/328 cases (17.4%) originated from the left posterior fascicle, 39/328 cases (11.9%) originated from the left posterior papillary muscle, 5/328 cases (1.5%) originated from multi-origin VAs, 3/328 cases (0.9%) originated from the left anterior fascicle, and 7/328 cases (2.1%) originated from other origins.Among 307/328 cases (93.6%) VAs patients receiving RFCA, 271/307 cases (88.3%) were instantly successful, 14/307 cases (4.6%) were effectively treated and 22/307 cases (7.2%) were invalid.During the follow-up time of 3 to 36 months, there were 42/271 cases (15.5%) recurrent cases.The mean radiation time and dose were (3.2±5.8) min, and (1.4±2.6) mGy, respectively.The mean dose-area product (DAP) was (384.2±42.6) mGy·cm 2.A total of 4/328 cases (1.2%) reported perioperative vascular complication.In 20 infant patients younger than 3 years, only 1 case was not induced during procedure of RFCA, and the remaining 19 cases were performed with RFCA, including 18/19 cases (94.7%) with an instant success and 4/18 (22.2%) recurrent cases during follow-up.There were 1/20 case (5.0%) had perioperative vascular complication caused by vascular puncture.No serious complications, such as myocardial perforation, cardiac tamponade and atrioventricular block were reported. Conclusions:The right ventricular outflow tract septum is the most common origin of the idiopathic VAs in pediatric patients.VAs originated from the ventricular outflow tract and tricuspid valve usually have an acceptable outcome following ablation.The recurrent rate is high following ablation in VAs cases originated from the left ventricular fascicle and posterior papillary muscle.RFCA is safe and effective for drug resistant or intolerant VAs in infants, but the surgical indications should be strictly mastered and operated by experienced pediatric electrophysiologists.The radiation dose of RFCA can be limited in a safe range under the guidance of the 3-dimensional mapping system.
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Objective:To identify the risk factors for cardiac events like recurrent syncope and fatal events in children with long QT syndrome (LQTS).Methods:A retrospective review involving 69 children with LQTS with the age of (7.6±4.2) years (43 male patients, 26 female patients) admitted in the Heart Center, Division of Pediatric Cardiology, First Hospital of Tsinghua University from August 2013 to March 2019 was conducted.Medical history, surface electrocardiogram, Doppler echocardiography and screening results of pathogenic genes of each patient were analyzed.Patients were divided into cardiac event group (32 cases) and non-cardiac event group (37 cases) according to the presence or absence of cardiac events like syncope or sudden death.Differences between 2 groups were compared using the independent sample Student′s t test and Chi- square test. Results:There were 32 cases among 69 children (46.4%) had recurrent syncope, involving 2 deaths, 14 cases among 69 children (20.3%) had a positive family history and 8 cases among 69 children (11.6%) had family history of sudden death.There were 52 cases among 69 children (75.4%) had arrhythmias.Among them, 32 patients (46.4%) with ventricular arrhythmia, including 11 cases (15.9%) with torsades de pointes (TdP). Ten LQTS-associated pathogenic or pathogenic pathologic mutations were found in 53 cases among 69 children (76.8%). Children with cardiac events had a younger mean age of onset [(4.7±4.1) years vs.(7.4±3.7) years, t=-2.856, P=0.006], a longer mean corrected QT (QTc) [(529±66) ms vs.(478±52) ms, t=3.537, P=0.001] and a higher incidence of TdP (34.4% vs.0%, P<0.001) compared with those who did not have cardiac events.Pathogenic mutations of KCNQ1 and KCNH2 were more frequent in children with cardiac events (62.5% vs.18.9%, χ2=14.178, P=0.001). Conclusions:Children with LQTS are prone to cardiac events.Children with a younger onset age, a longer QTc duration, malignant ventricular tachycardia and mutations of the KCNQ1 and KCNH2 genes are more frequently complicated by cardiac events.