Right ventricular function in patients with pulmonary regurgitation with versus without tetralogy of Fallot.

BACKGROUND: Right ventricular (RV) dilation from pulmonary valve regurgitation (PR) is common after intervention(s) for pulmonary stenosis (PS) or atresia and intact ventricular septum (PA/IVS). It is not well established whether PR and RV dilation have similar effects on RV function and exercise capacity in these patients compared to patients after repair of tetralogy of Fallot (rToF). The aims of this study were to compare exercise tolerance, RV function and myocardial mechanics in non-ToF versus rToF children with significantly increased and comparable RV volumes. METHODS: Thirty PS or PA/IVS children after intervention(s) with significant PR and RV dilation (non-ToF group) were retrospectively matched for RV end-diastolic volume index (RVEDVi) and age with 30 rToF patients. Clinical characteristics, RV function by echocardiography and CMR, ECG and exercise capacity were compared between groups. RESULTS: The groups were well matched for RVEDVi and age. Global RV function (RVEF: 48.7 ±â€¯6.4% vs. 48.5 ±â€¯7.2%, P = .81) and exercise capacity (% predicted peak VO2:82.5 ±â€¯17.7% vs. 75.6 ±â€¯20.4%, P = .27) were similarly reduced between groups. RVEDVi correlated inversely with RVEF in both groups (non-ToF:r = -0.39, P = .04, rToF:r = -0.40, P = .03). QRS duration was wider in rToF patients, and in both groups inversely correlated with RVEF (non-ToF:r = -0.77, P < .001, rToF:r = -0.69, P < .001). In contrast to global function, longitudinal RV strain was lower in rTOF vs non-TOF (-20.1 ±â€¯3.9 vs.-25.7 ±â€¯4.4, P < .001). CONCLUSIONS: Global RV function and exercise capacity are similarly reduced in non-ToF and rToF patients with severely dilated RV, after matching by RVEDVi, suggesting a comparable impact of RV dilation on RV global function. The significance of reduced RV longitudinal function and worse dyssynchrony in rToF patients require further exploration.

Cardiopulmonary Adaptation During First Day of Life in Human Neonates.

OBJECTIVE: To characterize the natural history of cardiopulmonary physiology in the first 24 hours after birth. STUDY DESIGN: A prospective observational study of healthy newborns was conducted at a large tertiary perinatal center. Echocardiography was performed at <0.5, 2-3, 7-10, and 22-24 hours of age. Specifically, assessment of pulmonary vascular resistance (PVR) (pulmonary artery acceleration time [PAAT], right ventricular ejection time, right ventricular ejection time:PAAT [PVR index], and PAAT indexed to heart rate [PAATi]), ventricular outputs (right and left), and ventricular function (tricuspid annular planar excursion, right ventricular [RV] fractional area change [FAC], RV/left ventricular [LV] global peak longitudinal strain, and LV ejection fraction) were performed. One-way repeated-measures ANOVA analysis was performed for time-dependent variables. RESULTS: In total, 15 neonates (9 males), born at 40 ± 0.8 weeks and 3.5 ± 0.5 kg, respectively, were studied. We observed increased PAATi (P < .05) by 2-3 hours, followed by a subsequent decline in all indices of PVR (PVR index, PAATi, midsystolic notching, and right-to-left ductal flow [P < .0001]). Although right and left ventricular stroke volume increased over the study interval (P < .001), LV output remained stable. All indices of RV function (tricuspid annular planar excursion, RV fractional area change 4-chamber, and RV global peak longitudinal strain-3 chamber [P < .001]) increased during the study interval. CONCLUSION: The immediate transition after birth is characterized by lower PVR, reversal of the transductal shunt, and increased biventricular stroke volume. The differential adaptive response of the RV and LV is novel and may relate to loading conditions and patent ductus arteriosus closure.

Echocardiography Grading for Pulmonary Arteriovenous Malformation Screening in Children with Hereditary Hemorrhagic Telangiectasia.

Transthoracic contrast echocardiography (TTCE) has high sensitivity but low specificity in screening for pulmonary arteriovenous malformations (pAVMs) in children with hereditary hemorrhagic telangiectasia (HHT). Here we describe characteristics of TTCE that might be used to reduce the need for confirmatory computed tomography scans in children with HHT.

Left Ventricular Function in Healthy Term Neonates During the Transitional Period.

OBJECTIVES: To evaluate whether incorporating conventional, tissue Doppler imaging and speckle tracking echocardiography are reliable and can characterize changes in left ventricular (LV) function properly in healthy neonates in the early transitional newborn period. STUDY DESIGN: A prospective observational study was conducted in 50 healthy term neonates with a mean ± SD gestational age and birth weight of 39.3 ± 1.2 weeks and 3.5 ± 0.44 kg, respectively. All infants underwent serial echocardiograms at 15 ± 2 (day 1) and 35 ± 2 hours (day 2) of age. The LV dimensions and various functional indices including tissue Doppler imaging velocities and speckle tracking echocardiography-derived peak longitudinal strain, and systolic and diastolic strain rate were acquired and compared between time points. RESULTS: All measurements were feasible from each scan except speckle tracking echocardiography in 10% and 20% of images on days 1 and 2 of age, respectively. LV dimensions, but not functional measures, demonstrated a small to moderate positive correlation with birth weight. On day 2, a small reduction was observed in LV basal diameter, mitral valve inflow velocity time integral, and systolic velocity of the lateral wall and septum. Other indices remained unchanged. Tissue Doppler imaging-derived functional and flow-derived hemodynamic measures demonstrated the least measurement bias, and strain measurements demonstrated better reliability than strain rate, fractional shortening, and ejection fraction. CONCLUSION: The relative reliability of various echocardiographic indices to quantify LV function in neonates establish a normative dataset and provide evidence for their validity during the first 2 days of life.

Assessment and treatment of post patent ductus arteriosus ligation syndrome.

OBJECTIVE: To compare differences in tissue Doppler imaging, global longitudinal strain (GLS), and cardiac troponin T (cTnT) between infants with low (<200 mL/kg/min) and high (>200 mL/kg/min) left ventricular (LV) output 1 hour after duct ligation and assess the impact of milrinone treatment on cardiac output and myocardial performance. STUDY DESIGN: LV function was assessed preoperatively and 1 and 18 hours postoperatively. Infants were categorized into a low-output or a normal-output group based on the echocardiographic assessment of LV output at 1 hour. RESULTS: Thirty infants with a mean gestation of 25.3 weeks were enrolled. LV basal lateral S', basal septal S', and basal right ventricular S' were lower in the low-output group (n = 19) at 1 hour postoperatively, with no significant difference in GLS (low-output -10.3% vs high-output -14.4%, P >.05) or cTnT between the groups. Patients in the low-output group were treated with milrinone, and by 18 hours LV performance recovered to levels comparable with the high output group. cTnT values increased at 18 hours in the whole cohort with no significant difference between the groups. CONCLUSION: Tissue Doppler imaging and GLS provide novel insights and further characterization of myocardial performance immediately after patent ductus arteriosus ligation. A reduction in tissue Doppler-derived LV systolic velocity may further help in monitoring cardiac performance after patent ductus arteriosus ligation and for monitoring the effects of treatment.

Safety and efficacy of clopidogrel in children with heart disease.

OBJECTIVE: To evaluate the efficiency and safety of clopidogrel treatment in children with heart disease. STUDY DESIGN: We conducted single center retrospective chart review of children with heart disease at the University Hospital, Leuven, Belgium, in whom clopidogrel was used. The indication, dosage, duration of therapy, and adverse events were examined. Clinical efficacy was defined by an absence of thrombotic events. RESULTS: 46 children were identified. The mean age of first clopidogrel dose was 4.9 +/- 4.1 years. The study dosage ranged from 0.1 to 0.7 mg/kg/day clopidogrel. Almost all patients received concomitant aspirin therapy. No thrombotic events developed. Skin bruising developed in almost every patient, suggesting that clopidogrel has an anti-platelet effect. 2 patients who were treated with concomitant warfarin had bleeding complications (severe epistaxis and gastrointestinal bleeding). Hematological abnormalities were documented in 1 patient who received clopidogrel for 1 year; they reversed with medication cessation. CONCLUSION: Clopidogrel therapy in a pediatric population appears to be relatively safe and effective; however, randomized, controlled prospective studies are needed to determine the true efficacy and safety of clopidogrel in children.