Pornthep Lertsapcharoen

Myocardial depression in dengue hemorrhagic fever: prevalence and clinical description.

Objectives: To determine the prevalence of myocardial depression and its effect on the clinical severity in patients with dengue hemorrhagic fever. Design: Clinical study. Setting: King Chulalongkorn Memorial Hospital, Bangkok, Thailand. Patients: Ninety-one children (age 10.5 ± 2.9 yrs, male/female = 52/39) with serologically or polymerase chain reaction-proven dengue virus infection. Interventions: Left ventricular ejection fraction (EF) was measured. The proportions of patients with EF <50% were identified in patients with dengue fever (DF, n = 30), dengue hemorrhagic fever without shock (DHF, n = 36), and dengue shock syndrome (DSS, n = 25). Comparisons of clinical findings were made among DSS patients with depressed ventricular function (EF <50%), fair ventricular function (EF ≥50% and <60%), and good ventricular function (EF ≥60%). Serum troponin T was analyzed in nine patients. Measurements and Main Results: EF during toxic stage was significantly lower in patients with DSS than DHF, and lower in DHF than DF (p = .05) with rapid recovery within 24–48 hrs. EF <50% was found in 6.7%, 13.8%, and 36% of patients with DF, DHF, and DSS during the toxic stage, respectively (p = .01). DSS patients with poor ventricular function had significantly more tachycardia and hepatomegaly. While end-diastolic volumes were similarly reduced, patients with lower EF tended to have lower cardiac output, required more aggressive intravenous fluid resuscitation, developed larger pleural effusion, and had higher incidence of respiratory embarrassment. No patient had elevated troponin T level. Conclusions: Transient myocardial depression is not uncommon in patients with DSS. Cardiac dysfunction in children with DSS may contribute to the clinical severity and the degree of fluid overload in these patients.

Spectrum of cardiac rhythm abnormalities and heart rate variability during the convalescent stage of dengue virus infection: a Holter study

Abstract Background: Various minor cardiac rhythm abnormalities have been reported in patients with dengue virus infection. Previous studies have used only random electrocardiograms (ECG) to assess the incidence of cardiac arrhythmias, and the time when the ECGs were undertaken was not systematically defined. Objectives: To evaluate cardiac arrhythmias and heart rate variability in children with dengue virus infection during the convalescent stage using Holter monitoring. Methods: Overnight 18–24-hour Holter monitoring was performed in 35 children [mean (SD) age 11·7 (2·3) y] at least 24 hours after defervescence (on the last day of admission). In 17 patients, time- and frequency-domain short-term (5 minutes) heart rate variability (HRV) during the convalescent stage was also compared with the value obtained during the follow-up visit (at least 14 days after defervescence). Results: During the convalescent stage, cardiac rhythm abnormalities were found in ten patients (29%), including sinus pause (1), first-degree (2) and Mobitz type I second-degree AV block (Wenckebach) (3) and atrial (4) and ventricular ectopic beats (5). There was no relationship between the clinical severity of dengue virus infection (DF, DHF without shock and DSS) and the incidence of cardiac arrhythmia. There was no significant difference in the averaged RR interval, the time-domain HRV (SDNN, RMSSD, pNN 50) or frequency-domain HRV (LF, HF, LF/HF ratio) between the convalescent stage and at follow-up. Conclusion: Various benign bradyarrhythmias and ectopic beats are detected in patients with dengue virus infection during the convalescent stage.

Hepatosplanchnic circulatory dysfunction in acute hepatic infection: the case of dengue hemorrhagic fever.

The mechanism of shock in patients with dengue hemorrhagic fever (DHF) has not yet been fully understood. In this study, we investigated the possibility of splanchnic venous pooling as a contributor for circulatory dysfunction in these patients. Ultrasonographic studies of portal vein and inferior vena cava were done in 45 patients with serologically or PCR-confirmed diagnosis of dengue virus infection. The size of portal vein and inferior vena cava, mean blood flow velocity in the right portal vein, and modified portal vein congestion index were compared between patients with dengue fever (DF, n = 20), DHF without shock (n = 14), and dengue shock syndrome (DSS, n = 11) during the toxic stage, convalescent stage, and at follow-up. The portal vein was significantly more dilated in patients with shock (DSS) than DHF without shock and than DF during the toxic and convalescent stages (P < 0.05), but not at follow-up. The change in the size of inferior vena cava followed the opposite trend (not statistically significant). Portal vein blood flow velocity was lower and congestion index was higher in shock cases (DSS) than DHF without shock and than DF at toxic and convalescent stages (P < 0.01). The differences disappeared at follow-up. Hepatosplanchnic venous pooling and/or dysfunction occur and correlate with the severity of circulatory derangement and shock in patients with DHF. The cause(s) and significance of hepatosplanchnic circulatory dysfunction in DHF and possibly other viral hepatic diseases deserve further study.

Endocarditis caused by drug-resistant Streptococcus pneumoniae in a child.

We report a case of infective endocarditis caused by drug-resistant Streptococcus pneumoniae. Cefazolin or cefotaxime therapy induced a partial response. Treatment with vancomycin was successful. This microorganism may be more significant in endocarditis in areas with a high prevalence of drug-resistant Streptococcus pneumoniae.

Bicuspidized Pulmonary Homograft for Truncus Arteriosus Repair

Primary repair is preferable to palliation in infants with truncus arteriosus. At our institute, an appropriately small homograft valved conduit is not available for every patient; a bicuspidized pulmonary valve homograft is an alternative. Between December 1996 and August 2005, 24 patients aged 28 days to 21 months with truncus arteriosus underwent primary repair with a homograft valved conduit; bicuspidized homografts were used in 15 of them. In the 18 (75%) patients who survived to hospital discharge, 5-year survival was 94% (75% for tricuspid homografts and 100% for bicuspidized homografts, which was not significantly different). Freedom from reoperation or balloon angioplasty in all 18 survivors was 89% at 5 years. Freedom from reoperation in tricuspid and bicuspidized homograft groups at 5 years was 67% and 100%, respectively; the difference was not statistically significant. Bicuspidized homografts worked as well as tricuspid conduits in the intermediate term. The remodeled homografts showed excellent hemodynamic characteristics and appear to be a reasonable alternative when an appropriate size of valved homograft is unavailable.

Clinical presentation and course of long QT syndrome in Thai children

Congenital long QT syndrome (LQTS) is a genetically transmitted cardiac channelopathy that can lead to lethal arrhythmia and sudden cardiac death in healthy young people. The clinical characteristics of LQTS are variable and depend on the subtype of long QT syndrome, which differ among populations. This single hospital‐based case review study examined the clinical presentation of long QT syndrome and the outcomes of its treatment in 20 Thai children at King Chulalongkorn Memorial Hospital in Bangkok, Thailand.

Transcatheter treatment of iatrogenic brachiocephalic-jugular arteriovenous fistula and aortopulmonary artery fistula: A case report

Iatrogenic arteriovenous fistula is not a common complication of central venous catheterization. Duct occluder devices have been developed for patent ductus arteriosus occlusions but they may be used for arteriovenous fistula closures. We report a case of iatrogenic brachiocephalic‐jugular and aortopulmonary artery fistulas after central venous catheter insertion. The fistulas were successfully managed with duct occluder devices. Due to increasing number of central venous catheterizations, physicians should be aware of this uncommon complication. Transcatheter closing of brachiocephalic‐jugular and aortopulmonary artery fistulas by duct occluder devices seems to be a safe and feasible form of treatment.

The Norwood procedure for hypoplastic left heart syndrome: results of the King Chulalongkorn Memorial Hospital

Background: The Norwood procedure is often performed to treat hypoplastic left heart syndrome (HLHS). Only Blalock-Taussig (BT) shunt is used with the Norwood procedure in our institute. Objective: To analyze the first-stage palliation for HLHS. Patients and methods: The Norwood procedure with right modified BT shunt was performed in 26 patients with HLHS between August 1996 and November 2008. The first four patients were performed using only autologous great vessel tissue (group 1), and the other 22 patients were operated with the Norwood procedure using a homograft for arch reconstruction (group 2). Results: The hospital mortality was 50.0 % in group 1 and 18.2% in group 2. The overall hospital mortality was 23.1%. Four out of twenty survivors (20%) had the modified Fontan procedure. Conclusion: Only a limited number of pediatric cardiac centers offered surgical treatment of the hypoplastic left heart syndrome. The survival rate in our study was in acceptable range despite the limited resource.