Evaluation of left ventricular contractile performance from baseline stress-shortening data in humans: comparison with pharmacological afterload challenge

The purpose of this study was to evaluate whether the baseline stress-shortening data reflect the contractile state adequately and give results comparable to the evaluation of the end-systolic stress-shortening relationships using pharmacological manipulation of afterload. Five groups were studied (total 152 patients): a control group of 30 healthy volunteers, 32 patients after surgical correction of infantile tetralogy of Fallot, 50 patients treated for childhood malignancies with doxorubicin, 17 patients with left ventricular hypertrophy due to systemic hypertension, and 23 patients with congestive cardiomyopathy. In all patients except those with congestive cardiomyopathy, afterload was altered pharmacologically to evaluate the individual stress-shortening relationship. In all patients the baseline stress-shortening data were evaluated, as well as their relative positions to two predefined normal ranges for the relationship between end-systolic stress and shortening. Additionally, a slope value was calculated from the baseline data of the five groups studied and compared with the data obtained by pharmacological afterload increment. Our data show that the comparison of individual baseline data of end-systolic wall stress and fractional shortening with predefined normal ranges for the relationship between end-systolic stress and shortening is inadequate. The appropriate normal range to compare with is the 95% confidence interval of baseline stress-shortening data in normal subjects. Also the calculation of a slope value from the baseline stress-shortening data of a group of patients seems to be inappropriate. Such a slope value does not necessarily reflect the contractile state, as the specific conditions leading to variations of end-systolic wall stress are undefined and not standardized, and the correlation between baseline stress-shortening data depends largely on the influence of the end-systolic dimension on both parameters.     

无心肌梗死冠心病患者心功能变化与室性心律失常的关系

目的：探讨冠心病心力衰竭对各种室性心律失常的影响。方法：选择381例冠心病住院患者，根据心功能分级标准（NYHA）分为4组，检测24h动态心电图（Holter），分析室性心律失常类型及发生率，进行统计分析。结果：各级心功能组其室性心律失常发生率经x^2检验示，室性心律失常的发生率除联律和持续性或非持续性室性心动过速外各组间差异无显著性（P＞0．05）。结论：非心肌梗死冠心病患者室性心律失常发作频率与心力衰竭的程度无关，但联律和持续或非持续性室性心动过速在重度心力衰竭患者发生率增加。     

血管紧张素转换酶抑制剂在急性心肌梗塞早期的应用

对２５例急性心肌梗塞（ＡＭＩ）并左心功能不全患者早期应用血管紧张素转换酶抑制剂（ＡＣＥＩ）治疗的对照性临床分析，结果：用小剂量的ＡＣＥＩ治疗对患者心率、血压无显著的影响〔治疗前后心率分别为８９．９０±１０．２２次／分与８９．４２±８．１９次／分，血压分别为１５．３７±３．４６／９．７４±２．３２ｋＰａ（１ｋＰａ＝７．５ｍｍＨｇ）〕和１４．９６±２．６０／９．４６±１．７６ｋＰａ〕；对合并轻、中度泵衰竭患者的疗效显著，但对重度泵衰竭的疗效与对照组比较无显著性差异；治疗组恶性心律失常的发生率较对照组减低１３．３８％，警告性室早的发生率治疗组较对照组减少２６．３９％，但Ⅱ°～Ⅲ°房室传导阻滞的发生率治疗组高于对照组；两组４周病死率比较无显著性差异。作者认为：ＡＣＥＩ治疗ＡＭＩ并轻、中度泵衰竭安全有效；ＡＣＥＩ有一定抗心律失常作用，但应注意传导系统的并发症，使用中应注意各种副作用的发生。     

Left ventricular growth in a patient with critical coarctation of the aorta and hypoplastic left ventricle

An infant is presented who at birth met criteria consistent with hypoplastic left heart syndrome. He was followed clinically and by 11 weeks of age demonstrated substantial growth of the left ventricle. He underwent successful repair of coarctation of the aorta and continues to do well with moderate aortic stenosis. The difficulties of predicting left ventricular growth and function are discussed, and management options are reviewed.     

Modified Damus–Kaye–Stansel procedure using aortic flap technique for systemic ventricular outflow tract obstruction in functionally univentricular heart

Damus–Kaye–Stansel procedure is a useful method to relieve the systemic ventricular outflow tract obstruction in functionally univentricular heart. Regurgitation of pulmonary valve and recurrence of systemic ventricular outflow obstruction are the major concerns at the late phase of this procedure. Modification of original Damus–Kaye–Stansel procedure that can prevent the use of prosthetic materials is evaluated. The modified Damus–Kaye–Stansel procedure using aortic flap technique was performed in eight patients with functionally univentricular heart. Patients’ ages ranged from 3 to 28 months (mean 14 months). Follow-up period was 37 months as a mean (9–71 months), and the follow-up was complete. There was no operative mortality and no late death. In addition, there was no recurrence of systemic ventricular outflow tract obstruction throughout the follow-up period. Regurgitation of the pulmonary valve estimated by echocardiography at the latest follow-up was none to trivial in seven patients and mild in one. The modified Damus–Kaye–Stansel procedure using aortic flap technique is a safe, useful and reproducible technique to solve systemic ventricular outflow tract obstruction in functionally univentricular heart, and it can be an alternative for original technique or the so-called double-barrel modification.     

TH胶胃冠状静脉栓塞术治疗门脉高压症

11例TH胶胃冠状静脉栓塞术临床治疗结果表明:(1)11例中的4例急性上消化道大出血患者均在12h左右出血基本停止,随访近一年未再发生出血现象。(2)10例半年后复查肝功能均有不同程度改善。(3)一年后复查食道钡餐透视X线平片发现8例患者食道静脉曲张有不同程度减轻。(4)11例中1例因术中急性肝功能衰竭死亡。因此我们认为此术式操作简便,手术创伤小、较易推广,是治疗门脉高压症合并食管胃底静脉曲张出血的一种有效方法。     

The Oxford Optical Pointer: a direction-sensing device with proportional electrical output

For some disabled people pointing provides a more convenient means of communication and control than the use of switches. The quadriplegic who retains good control of head movement can be provided with a number of input alternatives, but no existing system meets all the requirements of a general-purpose electronic pointing device. Consequently the Oxford Optical Pointer has been developed. The principle by which it converts relative direction into analogue electrical signals is described and its application as a head-mounted device for controlling an electric wheelchair is presented.     

动脉韧带与左喉返神经的解剖研究

本文用30例成人尸体观察了动脉韧带和左喉返神经,动脉韧带长1.2.97±4.53mm,圆索状动脉韧带23例(77％),直径为3.92±1.12mm。动脉韧带的主动脉端附着于主动脉弓(80％)或降主动脉(20％),肺动脉端附着于左肺动脉,6例肺动脉端位于心包内。19例(63％)左喉返神经绕主动脉弓,11例(37％)绕动脉韧带的主动脉端。     

Magnum system for routine coronary angioplasty: A randomized study

The Magnum system, initially designed for coronary angioplasty (PTCA) of chronic total occlusion, consists of a balloon catheter and a solid steel 0.021 inch (0.53 mm) steerable and removable wire with a soft and moldable distal portion, tipped with a 1 mm olive. To evaluate its performance in routine PTCA, 200 unselected consecutive patients were randomized to two equal groups, i.e., group Magnum (100 patients, 115 vessels) and group Standard (100 patients, 118 vessels) including 18 and 21 patients with chronic total occlusions, respectively. Randomization was performed by the sealed envelope system in the catheterization laboratory and crossover of system was imposed if it was not possible to place a balloon correctly within 20 min of fluoroscopy time. There were no significant differences between groups concerning clinical and angiographic baseline characteristics, size of initial balloons (3.0±0.3 mm in both groups), fluoroscopy time to cross the lesion with the wire (Magnum: 4±5, Standard: 5±6 min), total fluoroscopy time (Magnum: 11 ± 9, Standard: 12±12 min), and need for crossover (Magnum: 10%, Standard: 16%). Success rates per lesion were comparable with 90% in group Magnum and 84% in group Standard, as were the complications with one inhospital death in group Standard, occurring three weeks after PTCA and stent implantation. There was no emergency operation. Six patients per group had myocardial infarction of whom two in group Magnum and one in group Standard developed a Q-wave. The following variables were significantly in favor of the Magnum system compared with the Standard system: success rate in nontotal lesions (97% versus 90%) crossover success in total occlusions (0 vs. 33%), fluoroscopy time to cross the lesion with the balloon once the wire was in place (1 ± 2 vs. 2 ± 4 min), and use of a single versus 1.2±0.5 wires per lesion. The only advantage of the Standard systems was the more common use of 7 French guiding catheters (Magnum: 40%, Standard: 53%, p = 0.09). The Magnum system compares favorably with standard systems for routine PTCA. The robust design of the Magnum wire does not impair ease of placement and safety but saves material and facilitates balloon advancement across the lesion.     

Increased numbers of higher left intraocular pressures in 428 patients referred to the glaucoma clinic

Seventy-four per cent of 428 patients referred to the glaucoma clinic at Concord Hospital exhibited intraocular pressure (IOP) asymmetry. There was a preponderance of left eyes, in that two-thirds of the patients with asymmetrical pressures had the higher IOP in the left eye. As the degree of asymmetry increased, this trend became more pronounced. In addition, the statistically significant difference between right and left mean IOP among the glaucoma patients was not found among normal controls, even when the order of testing the eyes was reversed.