Impact of Obstructive Sleep Apnea on Global Myocardial Performance in Children Assessed by Tissue Doppler Imaging

This study aimed to assess the impact of obstructive sleep apnea (OSA) due to adenotonsillar hypertrophy (ATH) on the global myocardial performance in children using tissue Doppler imaging (TDI) and to evaluate the reversibility of the disorder after adenotonsillectomy (AT). The study included 42 children with OSA due to ATH (mean age, 5 ± 3.14 years) as the study group and 45 age- and sex-matched healthy children (mean age, 5.2 ± 3.08 years) as the control group. Polysomnography and echocardiography were performed. Indexed left ventricular mass (LVMi), pulmonary artery systolic pressure, mean pulmonary artery pressure (mPAP), and pulmonary vascular resistance (PVR) were calculated by echocardiography. Tissue Doppler imaging was used to determine the left ventricular and right ventricular myocardial performance index (MPI) of patients and control subjects before and after AT. The patients were classified into mild OSA (apnea-hypopnea index [AHI] 1–5; n = 18)] and moderate to severe OSA (AHI >5; n = 24) according to polysomnography findings. All the children in the control group had an AHI less than 1. They were treated using AT, then reevaluated by polysomnography and echocardiographic examination 6 to 8 months after surgery. Results are described as mean ± standard deviation. The patients with OSA had higher pulmonary artery systolic pressure, mPAP, PVR, LVMi, and right ventricular diastolic diameter than the control subjects. The patients with moderate to severe OSA showed more prominent changes than the patients with mild OSA, but the latter still differed significantly from the control subjects. The TDI-derived right ventricular MPI and left ventricular MPI measurements of the patients with OSA were higher (mean, 0.40 ± 0.08 vs 0.28 ± 0.01; p < 0.001) than those of the control subjects and (0.45 ± 0.05 vs 0.32 ± 0.05; p < 0.001) and correlated well with AHI and mPAP. In addition, mPAP was significantly correlated with AHI. Postoperatively, relief of OSA was validated by polysomnography, and a repeat of the echocardiographic parameters showed no significant differences between the patients and the control subjects. Tissue Doppler imaging can detect the subtle, subclinical changes in cardiac performance that occur in OSA due to adenotonsillar hypertrophy. Such changes generally are reversible after surgical treatment.     

Sequential Computed Tomography in Severely Asphyxiated Infants

Sequential CT scans were evaluated in four term infants with severe asphyxia, who subsequently developed neurodevelopmental sequelae. The initial CT scans performed within the first week of life showed poor visualization of the ventricles, diffuse but mild low density in the cerebral hemispheres and the falx image. In two of them, remarkably low density was seen in the basal ganglia and thalami in the second CT scans. The last CT scans demonstrated multicystic encephalomalasia in one case and brain atrophy with thalamic high density due to postichemic hypervascularity in the other. Of the other two cases, one showed low density in the fronto-temporal region in the initial CT scan and brain atrophy in the sequential scans. The other showed only transient periventricular low density. In conclusion, the morphologic changes seen in sequential CT scans continue until at least two months after birth and neonatal scans alone may not be useful for predicting the outcome.     

Correlation Between Right Ventricular Tei Index by Tissue Doppler Imaging and Pulsed Doppler Imaging in Fetuses

The aim was to compare the right ventricular (RV) Tei index obtained by the tissue Doppler imaging (TDI) method with that obtained by the pulsed Doppler method in 29 fetuses aged 24-39 weeks (29.9 +/- 4.0 weeks). From pulsed Doppler recordings, the tricuspid closing-to-opening time (a) and RV ejection time (b) were measured. The Tei index determined by the pulsed Doppler method was calculated as (a - b)/b. From TDI recordings, the time interval during diastole (a') and the duration of the systole S-wave (b') were measured. The modified Tei index obtained by TDI was calculated as (a' - b')/b'. The time a' correlated strongly with a (r = 0.90, p < 0.0001). The mean difference between a' and a was 0.3 +/- 5.0 ms. There was also a strong correlation between b' and b (r = 0.94, p < 0.0001). The mean difference between b' and b was 0.5 +/- 3.3 ms. The TDI-Tei index correlated with the pulsed Doppler-Tei index (r = 0.83, p < 0.0001). The mean difference between the TDI-Tei index and the pulsed Doppler-Tei index was -0.003 +/- 0.04. This study demonstrated that the TDI-Tei index correlates well with the Tei index determined by pulsed Doppler in fetuses, suggesting that the TDI-Tei index is a feasible approach to assess global RV function in fetuses.     

Evaluation of Myocardial Function by Pulsed Tissue Doppler in Kawasaki Disease

Myocarditis is a well-recognized component of Kawasaki disease, with left ventricular dysfunction occurring in more than half of patients during the acute phase. The purpose of this study was to evaluate myocardial function in patients with Kawasaki disease using pulsed tissue Doppler imaging (TDI). Twenty-five patients with the diagnosis of acute Kawasaki disease were enrolled in the study. All patients underwent echocardiographic studies at the time of diagnosis of the disease, in its acute phase, prior to treatment, and then 4 weeks later. For an aged-matched control group with fever and no cardiac disease, the same echocardiographic evaluations were performed. Peak velocities of systolic (Sa), early diastolic (Ea), and late diastolic (Aa) motion of the annulus were obtained at the lateral and septal sides in apical four-chamber view, and TDI-derived myocardial performance index (TDI-MPI) was also calculated. Peak Ea velocity of lateral mitral annulus was decreased significantly during the acute phase of illness (14 ± 4.40 vs. 17.67 ± 4.41; P = 0.028). In seven patients with carditis, changes in Ea-to-Aa ratio of septum (1.28 ± 0.278 vs. 1.78 ± 0.49; P = 0.018) and lateral mitral annulus (1.23 ± 0.496 vs. 2.11 ± 0.822; P = 0.014) were statistically significant but TDI-MPI showed no statistically significant changes. This study showed that peak mitral annular Ea velocities obtained by TDI were significantly altered in the acute phase of Kawasaki disease. TDI- MPI does not add an incremental benefit to other indexes of myocardial performance for comprehensive myocardial function in the acute phase of Kawasaki disease.     

Neurological Outcome in Full-Term Infants with Intraventricular Hemorrhage

Eight survivors among 12 full-term infants with intraventricular hemorrhage (IVH) were investigated for neurological handicap. Five patients developed epilepsy during the follow-up period of 4.5 years (range 2.0—6.8 years); four patients had an electroencephalogram (EEG) showing unilateral paroxysmal spikes, mainly in the central region, suggesting ventricular dilatation. The seizures were either partial, evolving to generalized seizures, or were generalized tonic-clonic seizures. Patients with either moderate ventricular dilation and/or grade III IVH with severe asphyxia had a poor developmental and neurological outcome.     

Tissue Doppler Imaging Detects Impaired Biventricular Performance Shortly After Congenital Heart Defect Surgery

Cardiac surgery with cardiopulmonary bypass is associated with the development of a systemic inflammatory response, which can lead to myocardial damage. However, knowledge concerning the time course of ventricular performance deterioration and restoration after correction of a congenital heart defect (CHD) in pediatric patients is sparse. Therefore, the authors perioperatively quantified left ventricular (LV) and right ventricular (RV) performance using echocardiography. Their study included 141 patients (ages 0–18 years) undergoing CHD correction and 40 control subjects. The study assessed LV systolic performance (fractional shortening) and diastolic performance (mitral Doppler flow) in combination with RV systolic performance [tricuspid annular plane systolic excursion (TAPSE)] and diastolic performance (tricuspid Doppler flow). Additionally, systolic (S′) and diastolic (E′, A′, E/E′) tissue Doppler imaging (TDI) measurements were obtained at the LV lateral wall, the interventricular septum, and the RV free wall. Echocardiographic studies were performed preoperatively, 1 day postoperatively, and at hospital discharge after 9 ± 5 days. Although all LV echocardiographic measurements showed a deterioration 1 day after surgery, only LV TDI measurements were impaired in patients at discharge versus control subjects (S′: 5.7 ± 2.0 vs 7.1 ± 2.7 cm/s; E′: 9.8 ± 3.9 vs 13.7 ± 5.1 cm/s; E/E′: 12.2 ± 6.4 vs 8.8 ± 4.3; p < 0.05). In the RV, TAPSE and RV TDI velocities also were impaired in patients at discharge versus control subjects (TAPSE: 9 ± 3 vs 17 ± 5 mm; S′: 5.2 ± 1.7 vs 11.4 ± 3.4 cm/s; E′: 7.3 ± 2.5 vs 16.3 ± 5.2 cm/s; E/E′: 12.5 ± 6.8 vs 4.8 ± 1.9; p < 0.05). Furthermore, longer aortic cross-clamp times were associated with more impaired postoperative LV and RV performance (p < 0.05). In conclusion, both systolic and diastolic biventricular performances were impaired shortly after CHD correction. This impairment was detected only by TDI parameters and TAPSE. Furthermore, a longer-lasting negative influence of cardiopulmonary bypass on myocardial performance was suggested.     

Usefulness of Indomethacin for Patent Ductus Arteriosus in Full-Term Infants

The aim of this retrospective study was to evaluate the effectiveness of indomethacin therapy for patent ductus arteriosus (PDA) in full-term infants. The patients were 41 full-term infants with a PDA birth weight (BW) > or =2500 g and a gestational age (GA) > or =37 weeks. The echocardiographic evaluation and medical management of PDA in these infants was similar to that for PDA in low-birth-weight infants. Indomethacin (0.2-0.25 mg/kg/dose) was given intravenously at 12-24-hour intervals within 23 days of birth. Of the 41 infants, 12 showed complete closure, and 13 showed improvement of clinical symptoms. These 25 infants were classified as the responder group (61%). The other 16 infants, who did not show improvement in clinical symptoms, were classified as the nonresponder group. Statistical analysis revealed no difference between the two groups regarding GA, BW, Apgar score at 1 minute, minimum diameter of the DA before treatment, the average age at the initiation of treatment, and DA flow pattern. No severe adverse reactions were observed in any infant. Indomethacin therapy appears to be an effective medical treatment option for PDA in full-term symptomatic infants prior to considering surgical treatment.     

多普勒组织成像法评价窒息新生儿左心收缩功能

目的探讨多普勒组织成像法(DTI)评价窒息新生儿左心收缩功能。方法足月窒息新生儿根据出生时Apgar评分分成重度窒息组(Apgar评分≤3分)共31例,轻度窒息组(Apgar评分4~7分)共31例,在出生后24、48、72h内分别通过超声心动图检测左室射血分数(LVEF),然后转入DTI模式测定二尖瓣前叶收缩期运动速度(s),并与正常新生儿组30例相对照,同时检测心肌肌钙蛋白(cTnⅠ)。结果重度组LVEF在24h明显低于48h和72h(P<0·001),亦明显低于轻度组和对照组(P<0·01),除此之外,3组之间及3组各时段之间LVEF差异无统计学意义(P>0·05)。DTI重度组、轻度组的s在3个时段均明显低于对照组(P<0·001),且重度组s在24h亦明显低于48h和72h(P<0·001),除此之外3组之间及3组各时段之间(s),差异无统计学意义(P>0·05)。重度组cTnⅠ在3个时段明显高于轻度组及对照组(P<0·01),而轻度组与对照组比较,差异无统计学意义(P>0·05)。结论新生儿窒息时左心收缩功能降低,DTI s较LVEF更能反映窒息新生儿左心收缩功能的变化。     

多普勒组织成像法评价窒息新生儿左心收缩功能

目的 探讨多普勒组织成像法（DTI）评价窒息新生儿左心收缩功能。方法 足月窒息新生儿根据出生时Apgar评分分成重度窒息组（Apgar评分≤3分）共31例，轻度窒息组（Apgar评分4-7分）共31例，在出生后24、48、72h内分别通过超声心动图检测左室射血分数（LVEF），然后转入DTI模式测定二尖瓣前叶收缩期运动速度（s），并与正常新生儿组30例相对照，同时检测心肌肌钙蛋白（cTnI）。结果 重度组LVEF在24h明显低于48h和72h（P〈0．001），亦明显低于轻度组和对照组（P〈0．01），除此之外，3组之间及3组各时段之间LVEF差异无统计学意义（P〉0．05）。DTI重度组、轻度组的s在3个时段均明显低于对照组（P〈0．001），且重度组s在24h亦明显低于48h和72h（P〈0．001），除此之外3组之间及3组各时段之间（s），差异无统计学意义（P〉0．05）。重度组cTnI在3个时段明显高于轻度组及对照组（P〈0．01），而轻度组与对照组比较，差异无统计学意义（P〉0．05）。结论 新生儿窒息时左心收缩功能降低，DTIs较LVEF更能反映窒息新生儿左心收缩功能的变化。     

Reaching and Asymmetrical Tonic Neck Reflex in Pre-Term and Full-Term Infants

No abstract available for this article.     

Wall Motion Velocities of Abdominal Aorta Measured by Tissue Doppler Imaging in Normal Children

Tissue Doppler imaging (TDI) offers a new technique for assessing aortic wall expansion/contraction velocities and may provide a noninvasive approach to aortic wall mechanics. The purpose of this study was to determine the normal values of abdominal aortic wall motion velocities and the effect of age on these velocities in normal children. We examined 103 normal children. Using TDI, maximum wall expansion velocity during systole (peak S) and maximum wall contraction velocity during diastole (peak D) were measured. M-mode diameter of the abdominal aorta and systolic, diastolic, and mean arterial pressures were measured. Aortic stiffness was measured as (I(n)[BP(syst)/BP(diast)])/(D(s)-D(d)/D(d), where I(n) is the natural log, D(s) is the maximal abdominal aortic diameter during systole, and D(d) is the abdominal aortic diameter at end-diastole. In all subjects, wall motion velocities of the abdominal aorta were recorded. The mean values for peak S and peak D were 4.23, 1.14 and 2.16, 0.45 cm/sec, respectively. Both peak S and peak D were low in infants and increased significantly with age (r = 0.63, p < 0.0001 and r = 0.36, p = 0.0002, respectively), systolic blood pressure (r = 0.42 and 0.47, respectively, p < 0.0001), and diastolic blood pressure (r = 0.24, p = 0.016 and r = 0.28, p = 0.0038, respectively). Aortic stiffness index of the abdominal aorta was constant with age and did not correlate with peak S or peak D. Abdominal aortic wall motion velocities can be easily assessed by TDI. Age-related changes in the aortic wall motion velocities are observed in normal children. This study provides baseline information for further quantitative assessment of arterial stiffness in children with congenital or acquired heart disease.     

Left Ventricular Systolic Function of Newborns with Asphyxia Evaluated by Tissue Doppler Imaging

The aim of the study was to evaluate the left ventricular systolic function of newborns with asphyxia using tissue Doppler imaging (TDI). Newborns with a history of asphyxia were divided into severe and mild groups based on their Apgar scores; normal newborns without asphyxia served as the controls. Left ventricular ejection fraction (LVEF), fraction shortening (FS), and stroke volume (SV) were measured by M-mode echocardiography at 24, 48, and 72 h after birth. The peak systolic velocity of the anterior mitral valve leaflet (Sm wave) was measured with TDI. Cardiac troponin I (CTnI) was measured. The results revealed that the LVEF and FS of the severe asphyxia group at 24 h were significantly lower than those at later time points (P < 0.01). These parameters were also significantly lower than those of the mild and control groups (P < 0.01). SV was not significantly different among the three groups. Sm wave of asphyxia groups was significantly lower than that of control group (P < 0.001). In the severe asphyxia group, Sm wave at 24 h was significantly lower than that at 48 or 72 h (P < 0.001). CTnI values of the severe asphyxia group were remarkably higher than those of the other two groups (P < 0.01). The findings of this study indicate decreased left ventricular systolic function of newborn children after asphyxia. Sm by TDI is a more sensitive indicator of left ventricular systolic function than LVEF, FS, or SV by M-mode echocardiography.     

口服吲哚美辛治疗足月儿动脉导管未闭的疗效

目的 探讨口服吲哚美辛治疗足月儿动脉导管未闭(PDA)的疗效.方法 选择2004年1月-2007年12月在本院新生儿科住院的经超声心动图确诊为PDA的足月儿41例,随机分为实验组(21例)和对照组(20例).实验组给予口服吲哚美辛片,0.2 mg/(kg·次),每12小时1次,共用药3次.对照组不予处理.二组用药前后2 d内复查肝肾功能和血常规;用药期间监测尿量及血糖,注意有无腹胀、呕吐、胃潴留及出血情况;用药5～7 d复查彩色多普勒超声心动图,听诊心脏杂音及观察临床征象变化;用药6-12个月进行门诊随访,复查彩色多普勒超声心动图,记录PDA闭合情况.结果 实验组用药前后2 d内复查肝肾功能和血常规均未发现异常.用药期间实验组仅1例在口服第2剂吲哚美辛后出现呕吐少许咖啡色样液体1次,未观察到其他不良反应.用药后5～7 d实验组PDA闭合16例,闭合率76.19%;对照组PDA自然闭合5例,闭合率25.0%,二组比较差异有显著性意义(X2=10.74 P<0.05);用药6～12个月门诊随访,实验组1例PDA重新开放.结论 口服吲哚美辛治疗足月儿PDA安全有效,不良反应少,使用方便.     

组织多普勒评价轻症病毒性心肌炎患儿左心室舒张功能

目的比较脉冲多普勒与组织多普勒对轻症病毒性心肌炎(VM)患儿左室舒张功能检测的价值。方法应用组织多普勒测量轻症VM患儿60例二尖瓣环侧壁处舒张早期和晚期运动峰值速度(Ea、Aa),计算Ea/Aa值;应用脉冲多普勒测量其二尖瓣口血流E、A峰流速(E、A)和E/A;并与40例正常儿童对照。结果组织多普勒显示患病组Ea峰值流速减低、Aa峰值流速增高、Ea/Aa值减低;脉冲多普勒显示E峰峰值流速减低、A峰峰值流速增高、E/A值减低。患病组28例Ea/Aa<1(47%),10例E/A<1(17%),组织多普勒评价轻症VM患儿左室舒张功能(u=3.53 P<0.01)。结论VM患儿早期即可出现左室舒张功能减退,组织多普勒评价左室舒张功能较脉冲多普勒更敏感、准确。