Effects of bile acids on ventricular muscle contraction and electrophysiological properties: studies in rat papillary muscle and isolated ventricular myocytes

Summary The effects of sodium salts of various bile acids on the contractile force and the electrophysiological properties of rat ventricular muscle were studied in vitro. Primary, conjugated, and secondary bile acids were studied in a concentration range of 10^–9–10^–6 mol/l, which corresponds to concentrations found in the plasm of patients with cholestatic jaundice. In general, the bile acid induced a negative inotropic effect which was manifested as a reduction in active tension, maximum rate of tension activation, and maximum rate of tension relaxation. Twitch duration and time to peak tension were unaffected by the bile acids. The negative inotropism was associated with a reduction in ventricular action potential duration. Resting potential, action potential amplitude, and maximum upstroke velocity of phase 0 depolarization were unaffected. Voltage clamp experiments in rat ventricular myocytes demonstrated that sodium taurocholate decreased the slow inward current and slightly increased the outward potassium current. Hence, these effects on the membrane currents are probably responsible for the negative inotropic effect. Send offprint requests to O. Binah at the above address     

TRH、EGF及地塞米松促进未成熟胎肺组织分化及表面活性物质合成的研究

目的 比较TRH、EGF与地塞米松对未成熟胎肺形态发育及表面活性物质水平的影响。方法 在兔妊娠第22－24d或第24－26d分别用TRH、EGF或地塞米松母体静脉注射治病，通过光镜、图像分析及电镜等技术观察胎肺的形态结构，并检测胎肺的磷脂水平。结果 光镜下，TRH、EGF与地塞米松治疗组第25d及27d胎肺肺泡腔、肺泡间隔发育均明显好于对照组；EGF、TRH与地塞米松治疗组第27d胎肺的肺泡腔与肺泡间隔的面积比无明显差异。但EGF和TRH治疗组第25d胎肺的肺泡腔与肺泡间隔之比明显小于地塞米松治疗组。电镜下，三个治疗组第27d胎肺内含有板层体的Ⅱ型上皮细胞数量明显多于对照组，但各治疗组及对照组第25d的胎肺Ⅱ型上皮细胞胞浆内几乎未见明显板层体，相反胞浆内糖原含量却非常丰富。此外，三个治疗组27d胎肺的磷脂水平均明显高于对照组。结论 EGF、TRH及地塞米松在兔妊娠第24－26d母体治疗均能促进胎肺的形态发育和表面活性物质的合成，三种治疗方法对胎肺的影响程序无明显不同；在妊娠第22－24d治疗，地塞米松对胎肺形态结构的促进作用较EGF和TRH更明显，但三者对Ⅱ型上皮细胞分化及表面活性物质的合成均无明显影响。     

Ventricular septal fistula formation due to infectious endocarditis in a hemodialysis patient with aortic valve replacement

We report a case of infectious endocarditis in a 77-year-old woman who was undergoing maintenance hemodialysis therapy, and who was also having a prosthetic aortic valve replacement. The disease resulted from a local skin infection at the needle puncture site of the arteriovenous fistula. Ampicillin-resistant Staphylococcus aureus was the causal organism. Surgical treatment could not be performed because of associated intracranial hemorrhage due to septic embolism. In spite of intensive treatment with several antibiotics, a ventricular septal abscess just beneath the prosthetic aortic valve progressed to form a ventricular septal fistula. The resultant intracardiac left-to-right shunt led to refractory congestive heart failure. The patient finally died of heart failure. The formation of a ventricular septal fistula is considered to be a rare and extraordinary complication of infectious endocarditis in a hemodialysis patient with aortic valve replacement. Received: July 25, 2001 / Accepted: November 3, 2001     

左心室巨大室壁瘤不同左心室成形方法的对比研究

目的研究左心室巨大室壁瘤的左心室成形方法,对改进的左心室心内膜环缩技术和传统的线性缝合技术进行近、远期疗效对比。方法自1992年1月至2004年12月,对148例左心室巨大室壁瘤患者进行手术治疗,按照手术中左心室成形方法不同分为两组,传统术式组:89例,采用传统的线性缝合成形技术;改良术式组:59例,采用改良的心内膜环缩成形技术,旷置梗死的心肌组织,再缝合环缩后的切口。采用多次信访、电话随访和门诊复查相结合的方法对两组患者术后的近、远期疗效进行对比观察。结果手术死亡5例(3.4%),其中传统术式组4例,改良术式组1例(P=0.320)。术后主要并发症为低心排血量和心室颤动。随访134例(93.7%),随访时间51.4±27.0月。远期死亡21例,术后早期心功能Ⅲ级以上是影响远期死亡的危险因素(P=0.000)。改良术式组5年和8年生存率明显优于传统术式组(91.6%vs.76.3%,P=0.040;91.6%vs.61.4%,P=0.000)。两组心功能分级(NYHA)和左心室射血分数(LVEF)术后早期和随访期间较术前改善和升高(P<0.05),改良术式组改善更明显。两组左心室舒张期末内径(LVEDD)术后早期与术前比较明显减小(P=0.000),但随访30个月时有重新增大的趋势(P=0.046)。传统术式组随访30个月时LVEDD扩大比率明显高于改良术式组(38.8%vs.16.7%,P=0.030)。结论左心室巨大室壁瘤的手术近、远期疗效满意,保持适当的左心室形态和容积是手术的关键。心内膜环缩法进行左心室成形是一种简单有效的手段,其远期结果优于线性缝合法。     

623例慢性前列腺炎患者的性功能状况调查

目的:了解慢性前列腺炎对早泄(PE)和勃起功能障碍(ED)的影响,探讨它们之间的关系。方法:依据美国国立卫生研究院慢性前列腺炎症状指数评分表(NIH-CPSI)、中国早泄患者性功能评分表(C ISFPE)、国际勃起功能问卷评分表(IIEF-5);采用和患者面对面交谈、询问,并分别记录623例慢性前列腺炎患者的NIH-CPSI评分、C ISFPE评分、IIEF-5评分。结果:623例18~57岁的慢性前列腺炎患者中,PE发生率为39.0%,其中轻度占26.2%、中度占12.0%、重度占0.8%;ED发生率为16.9%,其中轻度占14.9%、中度占1.0%、重度占1.0%。慢性前列腺炎患者PE的发生率以年轻者为多,18~29岁组为42.9%(103/240)、30~39岁为37.0%(95/257)、40~57岁组为35.7%(45/126);ED发生率以年龄高者为多,18~29岁组为13.8%(33/240)、30~39岁为11.3%(29/257)、40~57岁组为34.1%(43/126)。统计学分析发现,NIH-CPSI评分与早泄评分以及与IIEF-5评分均无明显相关性。结论:慢性前列腺炎的症状轻重与PE和ED的轻重程度无明显的相关性。     

Focal vulnerability of developing brain: CT studies on disproportionally dilated lateral ventricles

Summary Cranial computed tomography (CT) of 108 cases with dilated lateral ventricles was reviewed to elucidate the relationship between focal vulnerability of developing brain and disproportional dilatation of lateral ventricles. CT findings of 108 cases with symmetrical dilatation of lateral ventricles were classified into three types by morphometry of lateral ventricles: anterior horn predominant type (31 cases), diffuse type (36 cases), posterior horn predominant type (41 cases). Posterior horn predominant type has a tendency to occur in congenital anomalies and premature brain damage, and anterior horn predominant type in infantile brain damage. This disproportional dilatation of anterior or posterior horns suggests a vulnerability of periventricular structure in developing brain.     

炙甘草汤对大鼠室性早搏拮抗作用实验研究

目的：观察炙甘草汤对鸟头碱所致大鼠室性早博的预防和治疗作用。方法：成年SD大鼠50只，随机分为炙甘草汤大剂量组、中剂量组、小剂量组、生理盐水组、普萘洛尔组分别用相应药物及生理盐水灌胃5天后，匀速舌下静脉注射乌头碱，与生理参数分析仪相连接，观察心律失常的潜伏期及持续时间。结果：延长室性早搏的潜伏期炙甘草汤高、中剂量组与生理盐水纽比较有显著性差异（P〈0．05），普萘洛尔组与炙甘草汤高、中剂量组比较无显著性差异（P〉0．05）。缩短室性旱搏持续时间炙甘草汤高剂量组与生理盐水组比较有极显著差异（P〈0．01），炙甘草汤中剂量组与生理盐水组比较有显著性差异（P〈O．05），普萘洛尔组与炙甘草汤高、中剂量组比较无显著差异（P〉0．05），与生理盐水比较有极显著差异（P〈0．01）。结论：炙甘草汤对乌头碱所致大鼠室性早搏有一定的预防及治疗作用。     

Surgery for ventricular tachycardia in patients undergoing surgical ventricular restoration: The Karolinska approach

This article presents a review on the efficacy of surgical ventricular restoration and direct surgery for ventricular tachycardia in patients with left ventricular aneurysm or dilated ischemic cardiomyopathy. The procedure includes a non-electrophysiologically guided subtotal endocardiectomy and cryoablation in addition to endoventricular patch plasty of the left ventricle. Coronary artery bypass surgery and mitral valve repair are performed concomitantly as needed. In our experience, this procedure yielded a 90% success rate in terms of freedom from spontaneous ventricular tachycardia, with an early mortality rate of 3.8%. A practical guide to the pre- and postoperative management of these patients is provided. Electronic supplementary material The online version of this article (doi: ) contains supplementary material, which is available to authorized users.     

Atrial premature complexes and heart rate have prognostic significance in 1-month atrial fibrillation recurrence after electrical cardioversion.

AIMS: The aim of this study was to investigate the significance of simple 24-h Holter (24H) data after electrical cardioversion (CV) for atrial fibrillation (AF) recurrence. METHODS: We prospectively studied 47 consecutive patients subjected to CV, who successfully converted to sinus rhythm. All underwent echocardiography and 24H after CV. AF recurrence was studied at 14 days and 1 month by second 24H or by interim report of AF. RESULTS: About 53.2% remained in sinus rhythm (group I) and the rest recurred to AF (group II). Group I had fewer atrial premature complexes per hour (APC/h) (P = 0.002) and lower maximum (max HR), average, and minimum heart rates compared with group II (all Ps < 0.05). The optimal value of APC/h and max HR with best sensitivity and specificity was 32 APC/h and 90 bpm, respectively. These findings were the predictors of AF recurrence [hazard ratio (HR) = 4.5 with 95% CI = 1.7-11.7 and HR = 4.3 with 95% CI = 1.7-10.9, respectively]. Patients with the combination of both predictors had greater HR of AF recurrence compared with those with < 32 APC/h and max HR < 90 bpm (HR = 8.8 with 95% CI = 2.5-31.4). CONCLUSION: Patients with frequent APC/h and high max HR are at high risk for 1-month AF recurrence after electrical CV.     

Differences in arrhythmogenicity between the canine right ventricular outflow tract and anteroinferior right ventricle in a model of Brugada syndrome

BACKGROUND: The Brugada syndrome is characterized by ST-segment elevation on the ECG, especially in the right precordial leads sensitive to the right ventricular outflow tract (RVOT). OBJECTIVES: The purpose of this study was to evaluate the hypothesis that right ventricular electrophysiologic heterogeneity caused arrhythmogenicity in the Brugada syndrome. METHODS: Action potentials (APs) were mapped on the epicardium of 14 RVOT preparations and on the transmural surfaces of 15 pairs of RVOT and right ventricular anteroinferior (RVAI) preparations isolated from canine hearts. Brugada ECG and arrhythmias were induced with pilsicainide (2.5-12.5 micromol/L), pinacidil (1.25-12.5 micromol/L), and terfenadine (2.0 micromol/L). RESULTS: Low doses of drugs elevated the J-ST segment and induced APs with both short and long action potential durations (APDs) in contiguous RVOT epicardial regions. In addition, APs in the RVOT had a larger phase 1 notch and longer APD than in RVAI. The longest APDs were in the epicardium in RVOT but in the endocardium in RVAI regions. High doses of drugs eliminated the phase 2 dome of the AP and abbreviated APDs in the epicardium but not in endocardium and reduced the epicardial heterogeneity of APs but increased the transmural gradient of APD in 14 (93%) of the RVOT preparations. In contrast, abbreviations of epicardial APDs occurred in only 4 (27%) of the RVAI preparations. Ventricular tachycardia occurred more frequently in the RVOT (47%) than in paired RVAI preparations (7%). Blocking the transient outward current reduced the heterogeneity of APs and eliminated arrhythmogenicity in all preparations. CONCLUSION: Compared with the RVAI region, the RVOT has greater electrophysiologic heterogeneity that contributes to arrhythmogenicity in this model of Brugada syndrome.