Rekwan Sittiwangkul

Echocardiographic assessment of obstructive lesions in atrioventricular septal defects.

OBJECTIVES We sought to determine the accuracy of transthoracic echocardiography (TTE) in identifying risk factors in patients with an atrioventricular septal defect (AVSD). BACKGROUND Atrioventricular septal defect is a common lesion, and many decisions about it are based on echocardiography alone. The identification of associated left-sided inflow and outflow obstructive lesions is important, as they are responsible for mortality and morbidity. METHODS Between 1983 to 1998, 549 patients with AVSD underwent repair. The TTE findings were correlated with surgery, angiocardiography, autopsy or postoperative TTE. Papillary muscle measurements were made in those with either a left ventricular outflow tract (LVOT) or left ventricular inflow abnormality and compared with those measurements from control subjects. Measurements of the LVOT were made in patients with an identified LVOT abnormality. RESULTS There were 63 missed lesions, decreasing over time. Double-orifice left atrioventricular valve (DOLAVV) and nonobstructive chordae in the LVOT were more often missed. Reoperation was performed to address a missed lesion in 2 of 68 patients. Two of 55 patients died of reasons related to a missed lesion. In 67% of patients, DOLAVV was missed. Abnormal papillary muscle angles were seen with either a LVOT abnormality or DOLAVV. High insertion of the anterolateral papillary muscle was a risk factor for death or residual LVOT obstruction. Abnormal LVOT measurements were found in patients with tunnel obstruction and those with an acquired subaortic ridge. CONCLUSIONS Transthoracic echocardiography provides accurate preoperative information on AVSD.

Acute fulminant myocarditis in scrub typhus

Abstract Scrub typhus is a zoonotic disease caused by Orientia tsutsugamushi in which humans are accidental hosts. It is a febrile illness which is confined to rural Asia and the Western Pacific islands. Severe complications are very rare. We report four cases of acute fulminant myocarditis in children with scrub typhus. This complication led to severe cardiogenic shock and death in two of them. We believe this is the first report of fulminant myocarditis complicating scrub typhus in children.

Use of cardiac markers for monitoring of doxorubixin-induced cardiotoxicity in children with cancer.

The aim of this study was to evaluate N-terminal probrain natriuretic peptides (NT-pro-BNP), cardiac troponin T, and creatinine kinase, MB isoenzyme (CK-MB) in the determination of subclinical left ventricular (LV) dysfunction by echocardiography in patients treated with doxorubicin. We performed a cross-sectional case study of systolic, diastolic function and tissue Doppler imaging by echocardiography in children with cancer who received a certain cumulative dose of doxorubicin. Blood levels for NT-pro-BNP, cardiac troponin T, and CK-MB were analyzed within 6 hours of the cardiac study. Of 30 patients, 5 (16.7%) had LV dysfunction with an abnormally high NT-pro-BNP level of 363±78 pg/mL, whereas patients with normal LV function had an NT-pro-BNP level of 148±173 pg/mL (P=0.012). The NT-pro-BNP level not only inversely correlated with fractional shortening (r=−0.43, P=0.017) and ejection fraction (r=−0.45, P=0.013) but also correlated with mitral deceleration time (r=0.41, P=0.021) and a cumulative dose of doxorubicin (r=0.44, P=0.014). For tissue Doppler imaging, NT-pro-BNP correlated with a peak systolic velocity at the myocardial segment (Sm) (r=−0.40, P=0.027). NT-pro-BNP is a sensitive test and has a moderate relationship with the LV systolic and diastolic function, thus making it a useful cardiac marker for the monitoring of early anthracycline cardiotoxicity.

Heart rate variability in beta-thalassemia patients.

Background:  Cardiac failure remains the major cause of death in beta‐thalassemia major (TM). Reduced heart rate variability (HRV) is associated with a higher risk of arrhythmias after myocardial infarction and heart failure. We evaluated HRV in TM patients and its relationship with hemodynamics and echocardiographic parameters during a 6‐month follow‐up.

Delayed diagnosis of Kawasaki disease: risk factors and outcome of treatment

Abstract Background: Kawasaki disease (KD) is associated with a high incidence of coronary artery aneurysms in untreated children. Treatment with intravenous immunoglobulin (IVIG) within the 1st 10 days of illness reduces by approximately fivefold the prevalence of coronary artery abnormalities (CAA). Data regarding delayed diagnosis of KD in Thailand have not been reported in the literature. Aims: To determine the prevalence, risk factors and outcome of delayed diagnosis of KD in Thai patients. Methods: We retrospectively reviewed the medical records of patients at Chiang Mai University Hospital diagnosed as KD during 2000–2008. Patients were classified into two groups: Group I were diagnosed ⩽10 days of fever and Group II were diagnosed >10 days of fever. Results: Of 170 patients, 150 were in Group I [mean (SD) fever 7 (1·45) d] and 20 (11·7%) in Group II [mean (SD) fever 15 (4) d]. There were no statistical differences between the two groups in age, gender, number of KD clinical manifestations or laboratory results, except that Group II were of lower weight (p = 0·01). Group II were younger (p = 0·09) and had more incomplete criteria (p = 0·09) but the differences were not statistically significant. Group II had a higher incidence of CAA (75% vs 19%) (p<0·001), more severe CAA and more resistant cases (31·2% vs 9·5%) (p = 0·04). Conclusion: Patients with delayed diagnosis of KD have a higher risk of developing CAA and of a more severe outcome for coronary artery disease. Education is needed to make healthcare providers and physicians more aware of KD, especially in small children or those with incomplete KD.

Factors Influencing Survival in Patients after Bidirectional Glenn Shunt

Clinical characteristics, echocardiographic values, and catheterization data of 45 patients with a functional univentricular heart who had a bidirectional Glenn shunt instituted between November 1994 and October 2006 were retrospectively reviewed. Median age at operation was 20 months (range, 9 months to 19 years). Median follow-up time after the bidirectional Glenn operation was 4 years (range, 1 day to 11 years). The early mortality rate was 4/45 (8.9%); overall mortality was 24.4%. Actuarial survival after a bidirectional Glenn shunt was 73% ± 8% at 5 years and 55% ± 17% at 10 years. In multivariate Cox proportional hazards analysis, heterotaxy syndrome and systemic right ventricle were independent predictors of mortality after the bidirectional Glenn shunt. Age at operation, oxygen saturation, previous surgery, a pulsatile Glenn shunt, cardiopulmonary bypass, postoperative pulmonary artery pressure, bilateral superior venae cavae, and Nakata index were not predictive of mortality. The presence of heterotaxy syndrome and systemic right ventricle in patients with a functional univentricular heart should lead to aggressive investigation and management strategies.

Prenatal sonographic diagnosis of cardiac hemangioma with postnatal spontaneous regression

A 23-year-old pregnant woman, gravida 1 para 0, underwent ultrasound examination at 31 weeks’ gestation on account of antepartum hemorrhage. Ultrasound revealed normal fetal biometry, no placenta previa and normal amniotic fluid volume. On fetal echocardiography there was a slightly increased cardiothoracic ratio (0.6) and a slight left-axis deviation and pericardial effusion on the four-chamber view. In addition, there was an intracardiac echogenic mass 15 × 17 × 20 mm in diameter protruding from the left ventricular wall (Figure 1) near the apex. The vascular nature of the mass was demonstrable with color power angiography and the main feeding vessel was clearly visualized (Figure 2). Minimal ascites was observed. Other structures were normal. Cardiac hemangioma was prenatally diagnosed. On the follow-up scans at 33, 35 and 37 weeks’ gestation the cardiac size, pericardial effusion and ascites had not worsened but remained the same. Induction of labor was initiated at 37 weeks’ gestation and a healthy male fetus weighing 2770 g was delivered vaginally. Postnatal echocardiography demonstrated the tumor mass in the left ventricle arising from the pericardium with typical internal blood flow signals on color flow mapping. The main feeding vessels were clearly demonstrated. The heart was slightly enlarged. Magnetic resonance imaging (MRI) revealed the typical characteristics of a hemangioma. Ascites and pericardial effusion disappeared shortly after birth. The mass was scheduled to be removed later. However, at the age of 3 months the baby was still healthy without any signs of cardiac decompensation and the mass was smaller when compared with the cardiac size. On follow-up serial echocardiograms the tumor gradually regressed and completely disappeared at about 6 months of age. Cardiac tumors are rare; the prevalence, reported from autopsy studies of patients of all ages, varies from 0.0017% to 0.28%1. Rhabdomyoma is the most common benign fetal cardiac neoplasm, whereas hemangioma is extremely rare, occurring at a frequency of only 1 in 19 cardiac tumors1. Fetal cardiac hemangioma usually arises from the atrial wall or pericardium. Although several case reports of cardiac tumors have been published, very few cases of cardiac hemangioma have been diagnosed prenatally. Though benign in nature, cardiac hemangioma can obstruct inflow or outflow from the heart, leading to cardiac arrhythmia, cardiac decompensation or even hydrops fetalis. A tumor may interfere with blood flow through the heart by extrinsic compression or intracavitary obstruction and can be associated Figure 1 Fetal echocardiographic four-chamber view reveals an intracardiac mass in the left ventricle. IVS, interventricular septum; PE, pericardial effusion; Sp, spine.

Cardiac manifestations in HIV-infected Thai children.

Abstract Cardiac complications contribute significantly to morbidity and mortality in HIV-infected children. There have been few reports of cardiac manifestations in HIV-infected children in developing countries. The aims of this study were to evaluate the clinical manifestations and echocardiographic findings in Thai children with HIV infection and determine the clinical predictors of left ventricular dysfunction and pulmonary hypertension. We retrospectively reviewed the medical records of 27 infants infected with HIV perinatally who presented with cardiovascular problems at a tertiary care hospital between 1995 and 2000. The mean age at initial cardiac evaluation was 36 months (range 8-65). Signs and symptoms included dyspnoea in all cases, oedema in 12 (44%), finger clubbing in 11 (41%), cyanosis in 6 (22%) and S3 gallop in 8 (30%). Echocardiographic abnormalities included pericardial effusion in 12 (44 %), right ventricular dilatation in 12 (44%), pulmonary hypertension in 11 (41%), diminished left ventricular fractional shortening in 10 (37%), left ventricular dilatation in 9 (33%) and combined ventricular dilatation in 2 (7%). Left ventricular dysfunction did not correlate with HIV CDC classification, age, nutritional status or clinical signs and symptoms.

Prenatal Features of a Truncus Arteriosus With Pulmonary Atresia and Pulmonary Circulation Derived From the Ductus Arteriosus

truncus arteriosus is a solitary great artery arising from the base of the heart and supplying the systemic, pulmonary, and coronary circulation. A truncus arteriosus is a rare cardiac defect, accounting for less than 1% of structural heart defects.1 The single great artery usually arises above a malalignment ventricular septal defect (VSD) and straddles the ventricular septum. There is variability in the origins of the pulmonary branch and whether the aortic arch is interrupted. Van Praagh and Van Praagh1 suggested classifying trunci arteriosi with VSD into 4 types. In type I, a main pulmonary artery arises from the truncal root and bifurcates into the branch pulmonary arteries. In type II, the branch pulmonary arteries are separate from the truncal root. In type III, the left pulmonary artery is supplied by a collateral from the aortic arch and does not arise from the truncal root. In type IV, the aortic arch is interrupted. A truncus arteriosus may rarely occur without a VSD. Although prenatal diagnosis of a truncus arteriosus has been reported several times,2–4 to our knowledge, the rare variant with an atretic main pulmonary trunk and normal pulmonary circulation such as the case presented here has not been described prenatally. The objective of this report was to show abnormal fetal circulation associated with a truncus arteriosus with pulmonary atresia but with well-developed pulmonary circulation derived from retrograde flow through the ductus arteriosus.

Prenatal Diagnosis of Isolated Tricuspid Valve Atresia Report of 4 Cases and Review of the Literature

Objective. To describe the prenatal features of fetal tricuspid atresia. Methods. Four cases of fetal tricuspid atresia were prenatally diagnosed, sonographically described, and followed. Results. On the basis of this small series, the key findings for diagnosis included the demonstration of no patent tricuspid valve on the 4‐chamber view, no flow across the tricuspid valve on pulsed or color Doppler flow mapping, small right ventricles, and associated interventricular septal defects. Increased nuchal translucency thickness may give the first clue leading to follow‐up scans, resulting in a definite diagnosis. Conclusions. Tricuspid atresia can be readily diagnosed prenatally. The key findings and differential diagnoses are provided.