No Correlation Between Atrial Natriuretic Peptide Concentrations and Echocardiographic Measurements of Left Atrial Size or Left Ventricular Size and Function in Patients with Persistent Atrial Fibrillation

Atrial fibrillation (AF) may be associated with activation of atrial natriuretic peptide (ANP). The exact trigger for the release of ANP is still being debated. Atrial volume, pressure, and wall stretch are considered to be the main determinants of ANP activation. The aim of the study was to evaluate plasma ANP concentrations in patients with persistent AF and to analyze the echocardiographic determinants of ANP concentration in this group. The study population included 67 patients, 59 ± 7 years of age, with a median AF duration of 5.5 months (range 0.1–12). The relationship between plasma ANP concentrations and echocardiographic left atrial (LA) diameter and volume, and left ventricular (LV) diameter and ejection fraction (EF) was analyzed by logistic regression analysis. The median baseline plasma ANP concentration was 63 pg/mL (range 21–126) in the study group versus 34 pg/mL (range 16–73) in a control group. The mean left antero-posterior atrial dimension, LA volume, LV enddiastolic diameter, and LVEF were 48 mm, 104 mL, 52 mm, and 54%, respectively. A significant linear positive correlation was found between plasma ANP concentration and maximal LA volume (r = 0.62, P < 0.01). A negative correlation was found between LVEF and plasma ANP concentration (r =−0.42, P = 0.01). However, by multivariate regression analysis, no echocardiographic parameter was an independent predictor of plasma ANP concentration. Plasma ANP concentrations were independent of echocardiographic measurements of LA size or LV size and function in patients with persistent AF.     

Molecular basis of severe myoclonic epilepsy in infancy

Severe myoclonic epilepsy (SMEI) or Dravet syndrome is caused by mutations of the SCN1A gene that encodes voltage-gated sodium channel alpha-1 subunit. Recently, we generated and characterized a knock-in (KI) mice with an SCN1A nonsense mutation that appeared in three independent SMEI patients. The SCN1A-KI mice well reproduced the SMEI disease phenotypes. Both homozygous and heterozygous knock-in mice developed epileptic seizures within the first postnatal month. In heterozygous knock-in mice, trains of evoked action potentials in inhibitory neurons exhibited pronounced spike amplitude decrement late in the burst but not in pyramidal neurons. We further showed that in wild-type mice the Nav1.1 protein is expressed dominantly in axons and moderately in somata of parbalbumin (PV) – positive inhibitory interneurons. Our immunohistochemical observations of the Nav1.1 are clearly distinct to the previous studies, and our findings has corrected the view of the Nav1.1 protein distribution. The data indicate that Nav1.1 plays critical roles in the spike output from PV interneurons and further, that the specifically altered function of these inhibitory circuits may contribute to epileptic seizures in the mice. These information should contribute to the understanding of molecular pathomechanism of SMEI and to develop its effective therapies.     

脑出血后的抑制细胞凋亡干预

脑出血后血肿周围组织可发生继发性损伤。研究表明，细胞凋亡在脑出血后继发性损伤中起着重要作用。抑制细胞凋亡可显著改善脑出血后的神经功能缺损。     

顺平县11年间产后出血相关因素分析和防治措施研究

目的分析与产后出血相关的因素，提出合理的防治措施。方法以12600例产妇为研究对象，将胎儿娩出后2h内出血量达到或超过400ml，或胎儿娩出后24h出血量达到或超过500ml定义为产后出血，测量产后出血量。通过非条件Logistic回归分析，筛选出与产后出血相关的主要危险因素，对比出血发生率的变化。结果在12600例分娩产妇中，符合产后出血的有198例，单因素分析中有10个因素有统计学意义。结论加强孕前宜教和孕期管理，提高助产技术，规范缩官素在产前的应用，降低了产后出血的发生。     

超早期颅骨锥孔尿激酶冲洗治疗脑出血102例

目的总结超早期颅骨锥孔尿激酶冲洗治疗脑出血的经验与教训。方法对102例发病在6h内的脑出血病人,采用颅骨锥孔置管后,用尿激酶冲洗引流。结果恢复正常29例(28.5%),轻残36例(35.3%),重残20例(19.6%),植物生存5例(4.9%),死亡12例(11.8%)。住院治疗期间无一例复发和颅内感染。结论超早期颅骨锥孔尿激酶冲洗治疗脑出血,血肿溶解迅速,引流效果好,且不会破坏患者凝血机制。     

Pleomorphic Ventricular Tachycardia: Demonstration of Conduction Reversal Within the Reentry Circuit

A case is presented of a patient with incessant venfricular tacbycardia of left bundle branch block morphology. Endocardial mapping revealed the site of earliest activation during tachycardia to be the proximal right ventricular septum. Pacing at this site elicited the clinical tachycardia, whereas pacing at the proximal left ventricular septum induced a right bundle branch block morphology identical to that of a previously recorded spontaneous ventricuiar tachycardia. Electrophysiological evidence is given that both types of tachycardia originate from a single reentry circuit located in the proximal ventricular septum in which the reentrant wavefront may travel either orthodromically (during spontaneous tachycardia and right ventricular pacing) or antidromically (during left ventricular pacing).     

保留冠状动脉的猪心螺旋形心室肌带的解剖

Objective Based on the Helical Ventricular Myocardial Band (HVMB) theory proposed by Torrent-Guasp,the ventricular myocardial hand extends from the root of the pulmonary artery to the root of the aorta with two helical coils.This new theory is considered as a revolutionary concept for further understanding the global, three-dimensional and functional architecture of the ven- tricular myocardium. No repot had described techniques for disecting HVMB while keepin～ the integrity of the coronmy artery sys- tern. We explored techniques for dissecting HVMB in swine.Methads 33 fresh swine hearts were randomly divided intoll groups, 3 bearts in each. 160% barium sulfate (type I)suspmmion was injected into the coronary artery system. The coronary arteries were li- gated. The strial tissue was removed following puuing the hearts in boiling water then cooling for several hours. The superficial coro- nary vessels and fat tissue around the atrio-ventricular taxi inter-ventricular sulcus we～'e preserved. Some branches of the left anterior descending artery, distal segment, of posterior descending branch, and middle and distal segment of obtuse marginal branches were mu- tilated appropriately. HVMB dissection was completed with fingers in accordnce with Torrent Guasp' s technique. Results A contin- ued bundle of muscle, originated at the root of pulmonary artery and ended at the root of aorta, was unwrapped along the major dire- tion of the cardiac muscle fiber in all of the 33 hearts with spating of the coronary artery. The swine hearts' ventricular myocandium was cumosed of two loops, with basal loop firm the root of the pulmonart artery to the anterior papillary muscle and apical from the beginning of the anterior papillary muscle to the root tithe aorta. Each loop consisted of two segments: the right segment-coincid- ing with the right ventricular free wall and the left segment-coinciding with the basal d the left ventricular free wall. Posterior papillary muscle, which belongs to the descendant segment, denmrcated the border between the descendent and the ascendant of the HVMB's apical loop. Conclusion Although controversies about the theory of the HVMB remain, we have dissected the HVMB in the swine hearts' ventricular myocardium successfully with sparing of the coronary artery systems. This dissection procedure provides technical information for the studies of associated diseases based on the theory of HVMB.     

平衡法门控心血池显像评价不同分级前壁心肌梗死患者左室收缩及舒张功能

目的我们应用平衡法门控心血池显像技术对不同Killip分级的前壁心肌梗死患者进行左室总体和局部收缩和舒张功能参数的对比分析。方法对照组15例（G0）,前壁心肌梗死KillipⅠ级17例（G1）,前壁心肌梗死KillipⅡⅢ级12例（G2）。利用平衡法门控心血池显像技术评价3组的左室总体和局部的收缩与舒张功能。结果①左室整体收缩功能,在LVEF,ESC 2个参数中,G1比G0有显著差异（P<0.05）,G2分别比G1和G0有显著差异（P<0.05）。在PER、1/3EF、1/3ER 3个参数中,G2分别比G1和G0显著下降（P<0.05）。②左室总体舒张功能,在PFR、1/3FF、1/3FR、EDC中,G1比G0有显著差异（P<0.05）,G2分别比G1和G0有显著差异（P<0.05）。③左室局部收缩功能,在以LVREF为参数时,G1在4个节段比G0显著差异（P<0.05）,G2在所有6个节段中比G1和G0均显著下降（P<0.05）。④左室局部舒张功能,在以LVR1/3FF为参数时,G1在4个节段比G0显著下降（P<0.05）,G2在所有6个节段比G0和G1均显著下降（P<0.05）。结论前壁心肌梗死后出现心功能受损或心力衰竭的主要原因为左室重构。     

Characteristics of the Nonselective Cation Current （NSCCs） in Rabbit Left Ventricular Epicardial, Midmyocardial and Endocardial Myocytes

Objectives Recent studies have described regional differences in the electrophysiology and pharmacology of ventricular myocardium in canine, feline, rat, guinea pig, and human hearts. This has been shown to be due to a smaller IKs and a lager sodium-calcium exchange current (INa-Ca) and late INa in M region (deep subepicardial to midmyocardial). Studies from our laboratory have found a new repolarization current-nonselective cation current (NSCCs) existing in rabbit right ventricular myocytes. Methods We examined the characteristics of NSCCs in epicardial, M region, and endocardial cells isolated from the rabbit left ventricle with standard microelectrode and whole-cell patch-clamp techniques. The permeability to Na , K , Li , Cs but not to Cl- indicating that it was a nonselective cation current. Gd3 (0.1 mmol/l) and La3 (0.1 mmol/l) can block the current markedly. Results Further characterization of NSCCs was significantly smaller in M cells than in epicardial and endocardial cells. NSCCs current density was significantly smaller in M cells than in epicardial and endocardial cells. With repolarization to -80 mV, INs current density was (-0.44±0.05) PA/PF in endocardial cells, (-0.12±0.05) PA/PF in M cells and (-0.28±0.07) PA/PF in epicardial cells; and with repolarization to 30 mV, INs current density was (1.09±0.29) PA/PF in endocardial cells, (0.38±0.09) PA/PF in M cells and (0.91±0.32) PA/PF in epicardial cells. Conclusions Transmural dispersion of repolarization was due to the heterogeneity of NSCCs in rabbit left ventricle epicardial, endocardial myocytes and M cells. These findings may advance our understanding of the ionic basis for our understanding of factors contributing to the development of cardiac arrhythmias.