Visualisation of intra-cardiac structures and radiofrequency lesions using intracardiac echocardiography.

AIMS: Fluoroscopy does not allow identification specific anatomical landmarks during electrophysiological studies. Intra-cardiac echocardiography permits visualization of these structures with excellent accuracy, but the optimal method has not been fully described. The aim of this study was to assess the capability of intra-cardiac echocardiography for the visualization of such structures using two different approaches. We also assessed its capability for the evaluation of radio frequency lesions 20 min after catheter ablation of the cavo-tricuspid isthmus. METHODS: Intra-cardiac echocardiography was performed using a 9 MHz rotating transducer in eight consecutive patients (age range: 37-76 years) after radio frequency ablation of the cavo-tricuspid isthmus. The ultrasound catheter was inserted through the femoral vein into the superior vena cava and was pulled back to the inferior vena cava. The echo catheter was then reinserted through the subclavian vein and advanced into the right ventricular apex and was pulled back from the right ventricular to the superior vena cava. Qualitative evaluation and intra-cardiac measurements were performed off-line. RESULTS: The fossa ovalis, the tricuspid valve, and the terminal crest were visible in all patients regardless of the method of introduction of the echo catheter. Left-sided structures were less accurately seen by intra-cardiac echocardiography. The horizontal diameter of the fossa ovalis was 8.9+/-1.8mm. The cavo-tricuspid isthmus was visible using the femoral approach in three patients. The isthmus could be visualized in all patients, and in three patients together with the ostium of the coronary sinus, using the subclavian approach. radio frequency lesions were not visible 20 min after ablation. Additionally, both the left and right ventricles could be seen using the subclavian approach. CONCLUSIONS: The subclavian approach is feasible, safe and superior to visualize the isthmus. Twenty minutes after radio frequency ablation of the cavo-tricuspid isthmus radio frequency lesions are not visible using intra-cardiac echocardiography.     

1,6-二磷酸果糖治疗婴幼儿肺炎心衰疗效观察

应用脉冲多普勒超声心动图对３０例使用１，６－二磷酸果糖的肺炎心衰患儿进行心室舒缩功能指标的观测，并以２０例常规治疗的心衰患儿及２０例正常儿为对照组，评价１，６－二磷酸果糖的疗效。结果表明，１，６－二磷酸果糖能明显改善ＰＥＰ、ＰＥＰ／ＥＴ、ＰＥＰ／Ｒ－Ｒ、ＦＶＩ和ＳＶ等心室收缩功能指标及ＰＦＶＥ、Ｅ／Ａ、ＰＦＶＡ等心室舒张功能指标，使心功能恢复正常。１，６－二磷酸果糖对肺炎心衰引起的心肌缺血、缺氧有保护作用。     

Role of Papillary Muscle Dysfunction in the Pathogenesis of Mitral Regurgitation in Myocardial Infarction:

To elucidate the pathogenesis of mitral regurgitation (MR) after myocardial infarction (MI), the incidence of papillary muscle dysfunction (PMD), mitral annular size, and the extent of wall-motion abnormalities were examined in 81 patients with previous MI by two-dimensional echocardiography and real-time two-dimensional Doppler flow imaging. The prevalence of pathological MR was lower in patients with anterior MI (36%) than in those with inferior (65%) or anterior and inferior MI (88%) (P < 0.01 vs anterior MI group). The incidence of PMD in patients with MR in the anterior MI group (15%) was lower than that in the inferior (50%, P < 0.01) or anterior and inferior MI group (43%, P < 0.05). The mitral annular dimension in patients with MR was significantly greater than in those without MR, but it was similar among the three groups. The extent of wall-motion abnormality correlated significantly with the area of MR jet in the anterior MI group (y = 3.1x + 15.5, r = 0.52, P < 0.01) and in the inferior MI group (y = 8.3x + 32.7, r = 0.57, P < 0.01). However, the slope of this relationship was significantly steeper in the inferior MI group than in the anterior MI group (P < 0.05). These results indicated that the degree of MR with inferior MI was greater than with anterior MI for a given MI area. PMD may play an important role in the higher prevalence and greater degree of MR in inferior MI.     

超声心动图测定未闭动脉导管内径及临床意义

目的　探讨超声心动图测定未闭动脉导管内径的可靠性及其在导管法封堵动脉导管未闭症 (PDA)中的临床意义。　方法　 4 4例 PDA患者 ,男 18例 ,女 2 6例 ,平均 10 .8± 10 .5岁。应用二维超声心动图 (2 DE)及彩色多普勒血流显像 (CDFI)测定 PDA近端及最小内径 ,并与 X线造影测值及最终所选择的封堵器直径比较。　结果　 2 DE及 CDFI显示 PDA解剖全程及测量 PDA内径的成功率分别为 5 7%和 10 0 % ;2 DE对 PDA直径测量的均值显著低于 X线测值及封堵器实际尺寸 ,其回归方程斜率更偏离 1,截距较大 ,估计标准误高 ;CDFI对 PDA直径测量的平均值与 X线测值差异无显著性 ,但平均小于封堵器尺寸 2 .9mm,其回归方程斜率更接近 1,截距小及估计标准误小。　结论　与 2 DE相比 ,CDFI能更准确地测量 PDA直径 ;在导管封堵术中选择封堵器时 ,CDFI的 PDA直径测值可与 X线测量互相补充甚至可替代 X线造影 ,避免穿刺股动脉的技术困难及大量注射造影剂的副作用     

Familial homozygous hypercholesterolemia: clinical and cardiovascular features in 18 patients

Homozygous familial hypercholesterolemia (HFH) is a very rare autosomal dominant disease characterized by accelerated severe atherosclerosis. We examined 18 patients from 9 families with HFH. The age range was 6-30 years (mean = 16 years). Male to female ratio was equal. All patients had huge, multiple tuberous xanthomas on the skin and tendons. Mean +/- standard deviation of plasma cholesterol, triglycerides, low-density lipoproteins (LDL), and high-density lipoproteins (HDL) cholesterol levels were 608 +/- 89, 122 +/- 39, 550 +/- 88, and 26 +/- 8 mg/dl, respectively. Five patients (28%) had angina pectoris, two sustained a myocardial infarction, and one died at the age of 15 years. Two-dimensional echocardiography demonstrated supravalvular aortic stenosis in 3 of the 13 patients (23%). Coronary arteriography performed in 11 patients demonstrated significant obstruction in 6 patients, 2 each with single-, double-, and triple-vessel disease. Left main stenosis was present in 3 patients (27%). Supravalvular aortic narrowing was demonstrated in 6 patients (54%) and was associated with a gradient in 2 (25 and 35 mmHg, respectively). Segmental contraction abnormalities were detected in 2 of the 11 patients (18%). It is concluded that coronary artery disease is prevalent in patients with HFH and, based on the data presented, we recommend the performance of noninvasive technique, coronary arteriography and supravalvular aortography at an early age to detect and to follow the progression of the disease.     

超声引导心脏靶点起搏和精确消融的初步实验研究

目的 初步建立超声引导监控下的心脏传导系统的靶点起搏和精确消融方法。方法 12只杂种犬急性开胸模型，经颈静脉插入超声导管分别进入上腔静脉，右心房，室或经心脏表面进行心脏扫描，获取并确认心脏传导系统超声解剖结构标志及其心肌激动顺序，确定靶组织空间益关系，引导经股静脉插入的心脏起搏或消融导管和经心脏表面插入的穿刺针到达靶组织并确认心内膜面接触，进行靶点起搏，精确射频及化学消融，超声实时监控全过程，对心脏离体标本进行病检和切片，确认靶点起搏位置，观察消融和起搏对心脏传导系统和组织细胞的损害。结果 超声能够在观察到心脏传导系统重要靶点部位，解剖结构的同时评价其结构内心肌激动的起始和传导顺序，能引导介入导管准确到达靶点组织，监控电极与心内膜央的接触，监控穿刺针在靶点组织内的准确空间位置，避免损伤冠状动脉及传导组织，及时评价起搏和消融损伤效果。确定终止治疗时机并监控并发症的发生，病解和切片表明超声引导心脏射频和化学消融定位准确，效果肯定。结论 超声能够引导心脏介入导管和穿刺针进行心脏靶点起搏和精确消融，定点消融心肌，使起搏和消融治疗更为精确，该方法将为临床心脏电生理疾病的治疗提供一种全新的简便，准确技术方法和手段。     

超声心动图对62例房间隔缺损封堵术后心功能变化的评价

目的：应用超声心动图评价房间隔缺损(ASD)封堵术前后左、右心室功能的变化。方法：对62例成功施行经皮穿刺ASD封堵术的患者进行研究。所有患者在术前、术后1周及1个月分别进行超声心动图检查．观察心脏大小及功能的改变。结果：ASD封堵术后，左室舒张末期前后径、左室舒张末期容积、左室每搏量及左室射血分数增大，而左室收缩末期容积未见明显改变；右室舒张末期前后径、右室舒张末期容积、右室收缩末期容积、右室每搏量、右室射血分数及右室心肌工作指数均减小。结论：经皮穿刺ASD封堵治疗既可减轻右室容量负荷，改善右室功能，也可改善左室的收缩功能：超声心动图对ASD封堵前后心脏血流动力学评价及疗效的观察起了重要的作用。     

Non-invasive estimation of the diastolic elastic and viscoelastic properties of the left ventricle

The present study applies a non-invasive method to the quantitative evaluation of left ventricular stiffness in normal subjects and in patients with ischaemic heart disease (IHD). We have studied 20 patients with IHD and 25 healthy subjects. The third heart sound (S3) was detectable in all patients. We have correlated the energy spectrum of S3, divided into 15 Hz bands, with a series of echocardiographic parameters. The existence of a significant correlation between the spectrum energy and the diameter and thickness of the left ventricle at the moment of S3 allowed us to explore the possibility of interpreting the origin of S3 based on a mathematical model. Our hypothesis has been that, once the left ventricle starts vibrating, it behaves as a simple physical model composed of a mass and an elastic element. To this purely elastic model one can add a factor accounting for viscosity, with a damping effect, to obtain a more complex viscoelastic model. The stiffness coefficient 'k' was computed in both models from the peak frequency of S3 and the left ventricular mass at the moment of S3. Furthermore, in the viscoelastic model, the damping element 'c' was also computed. Both parameters--k and c--were significantly increased in the group with IHD compared with the control group. Although a simplification of the vibrating system, these models make it possible to obtain non-invasively information on the characteristics of the left ventricle through the combined use of echocardiography and spectral analysis of S3.     

Mitral insufficiency with congenital double-orifice mitral valve in an elderly patient.

We describe the case of a 79-year-old woman with mitral insufficiency and a double-orifice mitral valve (DOMV), discovered by echocardiography. Transthoracic echocardiography showed two insufficiency jets. Transesophageal echocardiography revealed a DOMV. Each orifice was provided with a subvalvular apparatus. No associated congenital abnormalities were present. Our case demonstrates that even in elderly patients with a double regurgitant jet, DOMV should be suspected and assessed by transesophageal echocardiography.