Idiopathic left ventricular tachycardia in children.

BACKGROUND: Idiopathic left ventricular tachycardia (ILVT) is a rare but well-recognized clinical entity. The clinical characteristics and prognosis of this form of ventricular tachycardia (VT) in Thai children is not known. OBJECTIVE: To define clinical presentations, drug therapies, roles of radiofrequency (RF) catheter ablation, and the short-term outcome of these children in Thailand. PATIENTS AND METHOD: From April 1999 to June 2007, 10 patients were diagnosed as ILVT by specific electrocardiographic features and therapeutic response. All patients had a structurally normal heart. Data were collected retrospectively. Baseline clinical information, 12-lead electrocardiography (ECG) during VT, responses to drug therapy, results of RF catheter ablation therapy, and outcome were determined. RESULTS: Median age at presentation was 9.5 years (range, 3.8 to 14.0 years). Three patients (30%) were male. Eight patients (80%) were diagnosed as supraventricular tachycardia (SVT) before ILVT diagnosis. Median duration from SVT diagnosis to the correct diagnosis was 1.5 years (range, 0 to 6.0 years). Palpitation and chest pain were usual clinical manifestations while congestive heart failure was the presentation in one due to incessant tachycardia. Two patients had recurrent VT episodes during acute febrile illnesses. The majority of patients responded to intravenous verapamil. RF catheter ablation was performed in 3 patients with recurrence of the VT in one. CONCLUSION: Prompt recognition of the ILVTespecially in the emergency department is very important. Verapamil is effective for acute termination as well as prevention of VT recurrence. When VT is refractory to medical therapy, RF catheter ablation is safe and effective. The short-term prognosis was good.

Predicted outcome after repair of tetralogy of Fallot by postoperative pressure ratio between right and left ventricle.

BACKGROUND: The surgical management of tetralogy of Fallot (TOF) has continued to evolve and there are now generally excellent early and long-term results following complete repair. OBJECTIVE: To investigate the early results of the authors' current surgical management of TOF by assessing the perioperative and early to intermediate follow-up period. The authors paid particular attention to the post-operative ratio of right ventricular to left ventricular systolic pressure (RVSP/LVSP), focusing on the presence of low cardiac output, intensive care unit (ICU) stay, prolonged of inotropic support and ventilation support time. STUDY DESIGN: Retrospective study. MATERIAL AND METHOD: Between June 2002 and August 2004, 31 consecutive patients underwent complete repair of TOF. Their mean age was 7.7 +/- 5.1 years (range, 2.9 to 25.3). A previous palliative shunt had been performed in 14 (45.2%) patients. Twenty-three patients (74.2%) were in NYHA FC II. Mean hematocrit and oxygen saturation were 50.9 +/- 10.25% and 80.5 +/- 8.6%, respectively. Mean preoperative ratio of RVSP/LVSP was 1.1 +/- 0.15. The operative approach was transatrial/transpulmonary, and 17 (54.8%) patients required a transannular patch. An extracardiac valve conduit was necessary in 3 (9.7%) patients with pulmonary atresia. RESULTS: There were no operative or late deaths. Two cases were reoperated from cardiac tamponade. Mean postoperative ratio of RVSP/LVSP was 0.53 +/- 0.16. Median ICU and hospital stays were 2.2 and 11 days, respectively. Presence of low cardiac output and prolonged inotropic support were significantly (P < 0.05) related to a RVSP/LVSP ratio of more than 0.5. At median follow-up of 6 months, 29 (93.5%) patients were asymptomatic and all patients were free of significant residual lesion. CONCLUSION: The authors' early results in complete repair of TOF patients are acceptable with a low incidence of morbidity. A postoperative RVSP/LVSP ratio of more than 0.5 was significantly associated to adverse outcome. Late complications may, however, develop, and long term follow-up for early detection of any such complications is essential.

A case report of infant with left ventricular noncompaction.

Left ventricular noncompaction (LVNC) is a rare cardiomyopathy resulting from abnormal arrest during endomyocardial embryogenesis. The authors present a 6-month-old infant with intractable cardiogenic shock and echocardiographic features of LVNC, characterized by excessively prominent ventricular trabeculation and deep intertrabecular recesses as the first case report in Thailand.

Early experience with pediatric cardiac intervention in Songklanagarind Hospital.

BACKGROUND: Nowadays, pediatric cardiac intervention is an effective optional treatment for congenital heart disease (CHD). Several cardiac centers have been established in different regions of Thailand and Songklanagarind Hospital is the newest of these university cardiac centers. OBJECTIVE: To report results and complications of transcatheter treatment for congenital cardiac defects in Songklanagarind Hospital. MATERIAL AND METHOD: The medical database was reviewed for the results and complications of different types of pediatric cardiac intervention from May, 2000 to December, 2003. RESULTS: There were 102 cases of pediatric cardiac intervention. Sixty-seven were patent ductus arteriosus (PDA), 16 were valvular pulmonary stenosis (VPS), 10 were cyanotic CHD which needed balloon atrial septostomy (BAS), 8 were abnormal aorto-pulmonary (AP) collaterals, and 1 was severe valvular aortic stenosis (VAS). Coil embolization was performed in 53 patients with PDA and 8 patients with AP-collateral vessels, 32 of PDAs (60.4%) and all AP-collateral vessels (100%) were completely obliterated within 24 hours. The Amplatzer duct occluder (ADO) was deployed in 14 PDAs with 100% completely obliteration within 24 hours. In those with VPS or VAS, percutaneous balloon valvuloplasty (PBV) was the treatment of choice. The mean peak to peak systolic pressure gradient in VPS was reduced from 62.8 +/- 33.3 mmHg to 33.33 +/- 33.33 mmHg and from 76 mmHg to 49 mmHg in VAS after the procedures. In BAS, the mean diameter of atrial communication increased from 3.0 +/- 0.7 mm to 5.9 +/- 0.4 mm. In coil embolization, 8 had distal PA embolization (15%), 1 had hemolysis (2%) and 1 had decreased dorsalis pedis pulse (2%). One (7%) of the ADO-implanted patients had a weak femoral pulse. Of the VPS cases, 1 died from intractable heart failure, and 1 developed hemiparesis, from which they completely recovered within 6 months. The patient with VAS had a femoral artery complication. CONCLUSION: Pediatric cardiac intervention in Songklanagarind Hospital has satisfactory results with an acceptable complication rate.

Dengue myocarditis.

We report a 13-year-old boy who developed bradycardia and hypotension a day after recovery from dengue hemorrhagic fever. His electrocardiogram, during the bradycardia, showed a junctional rhythm with a rate of 50 beats/minute. This is the first reported case of sinus node dysfunction following dengue infection.

Balloon-expandable stenting, percutaneous coil embolization, and amplatzer septal occluder; treatments after complicated lateral tunnel Fontan: a case report.

The authors report a 7-year-old girl with univentricular heart physiology who developed prolonged pleural effusion due to discrete narrowing of the proximal right pulmonary artery, and progressive cyanosis which resulted from leakage of the atrial baffle, multiple veno-venous collaterals after the lateral tunnel Fontan operation. Percutaneous balloon-expandable stent implantation was used to correct the right pulmonary artery stenosis with an excellent result. Cyanosis was improved by coil embolization of the collaterals and occlusion of the baffle leakage with Amplatzer septal occluder. This is the first successful report in Thailand.

The right and left ventricular function after surgical correction with pericardial monocusp in tetralogy of fallot: mid-term result.

BACKGROUND: Surgical repair of tetralogy of Fallot (TOF) with reconstruction of the right ventricular (RV) outflow tract invariably results in pulmonary regurgitation (PR). Chronic PR has been associated with RV dysfunction and ventricular arrhythmia. Pericardial monocusp has recently been used at Ramathibodi Hospital to preserve pulmonary valve function. OBJECTIVES: First, to study the competency of the pericardial monocusp, one-year after correction. Second, to assess the right and left ventricular (LV) functions after surgery. Third, to assess correlation between severity of PR and the characters of electrocardiography (ECG) and chest X-ray (CXR) after correction. METHOD: A cross-sectional study was conducted in patients who, had undergone total correction for TOF at least one year ago. The past medical history was retrospectively reviewed from the medical records. The patients who underwent surgical correction with and without pericardial monocusp were recruited into group I and group II, respectively. The clinical symptoms, QRS duration from ECG, and cardio-thoracic (CT) ratio from CXR were analyzed. From the echocardiographic standpoint, the LV systolic function was determined by LV fractional shortening (LVFS), whereas the RV systolic function was determined by the tricuspid annular plane systolic excursion (TAPSE). Restrictive physiology of the RV was determined by presence of antegrade flow across the pulmonary valve during diastole. RESULTS: Sixty four patients were enrolled in the study, 7 in group I and 57 in group II. The median follow-up time after the surgery was 6.5 years, which was 3 years in group I and 7 years in group II (p < 0.01). All patients in group I (100%) and 45 (80.4%) in group II had moderate or severe PR. The severity of PR, the RV and LV systolic functions were not statistically significantly different between the two groups (p > 0.01). The median of the LVFS was 32.4 per cent, and of the TAPSE was 10.5 mm. There was no restrictive physiology of the RV in all patients. There were no significant correlations between symptoms, CT-ratio, QRS duration and the severity of PR. CONCLUSIONS: The pericardial monocusp could neither reduce severity of PR nor improve right and left ventricular functions after 3 years follow-up post-operatively. However, the right and left ventricular performances in mid-term period remained insignificantly changed and severity of PR could not be predicted from symptoms and simple laboratory investigations.