先天性一侧肺动脉缺如的电子束CT诊断

目的 评价电子束CT(EBCT)诊断先天性一侧肺动脉缺如的价值。方法 对经平片、超声心动图检查后拟诊为肺血管疾病或原发性肺动脉高压的患者行EBCT检查，EBCT诊断先天性一侧肺动脉缺如的11例患者入选，并与超声心动图、核素通气灌注扫描、心血管造影的检查结果作进一步的比较及评估。结果 单发一侧肺动脉缺如4例，均为女性成年人。合并多发心血管畸形7例，其中合并复杂畸形3例，均为男性儿童和左肺动脉缺如；合并单发心血管畸形4例，其中3例为右肺动脉缺如。结论 (1)儿童时期明确诊断的一侧肺动脉缺如多合并有心血管畸形，且左肺动脉缺如多见，成年人明确诊断的单发一侧肺动脉缺如多为右肺动脉缺如。(2)EBCT对先天性一侧肺动脉缺如的诊断有较高的实用价值，较之多普勒超声更为准确，与心血管造影各具独特优势，但EBCT为无创检查是其特点。     

解耦联蛋白在心肌中的表达与心力衰竭

位于心肌线粒体内膜上的解耦联蛋白 (UCPs) ,作为质子通道驱散氧化呼吸时形成的H 梯度 ,使产能转化为产热 ,从而增加呼吸 ,阻止ATP形成 ,并抑制活性氧族的产生 ,最终阻止了心肌细胞的程序性死亡。脂肪酸、寒冷、甲状腺激素、肾上腺素等能调控UCPs的浓度和活性。UCPs在心力衰竭中的作用仍然不清楚 ,有待进一步研究     

Alteration of Elastin, Collagen and their Cross-links in Abdominal Aortic Aneurysms

OBJECTIVES: although the mechanism of arterial dilation and aneurysm development has not been clarified, the degradation of elastin and collagen plays undoubtedly a critical role. We evaluated the elastin and collagen content through the detection of their cross-links in aneurysmal and non-aneurysmal abdominal aortic walls. MATERIALS AND METHODS: in 26 human abdominal aortic aneurysm specimens obtained during surgery and in 24 autopsy control samples of non-aneurysmal abdominal aorta the tissue content of elastin and collagen cross-links were measured by HPLC. Collagen was also detected by evaluating two characteristic amino acids, 4-hydroxyproline (4-hypro) with a colorimetric method and 5-hydroxylysine (5-hylys) by gas chromatography. RESULTS: significantly fewer elastin cross-links were found in aneurysm samples compared to controls (desmosines and isodesmosines: 90% reduction; p<0.01). The opposite was true for pyridinoline collagen cross-links (350% increase) and deoxypyridinolines (100% increase, p=0.01). Tissue content of 5-hylys, 4-hypro and total amino acids were reduced significantly by 50% in aneurysmal samples. CONCLUSIONS: beside confirming decreased elastin content in aneurysmal walls, these results show a concurrent increase of collagen cross-links. Since total collagen markers were decreased (decreased 4-hypro and 5-hylys) it is reasonable to suggest that in aneurysmal aortic walls old collagen accumulates cross-links while new collagen biosynthesis is somehow defective.     

右心室不同部位起搏血液动力学改变的研究

目的：根据右心室不同部位起搏时血液动力学改变，研究选择置入右心室双部位起搏器辅助治疗心脏扩大合并充血性心力衰竭(CHF)，观察临床效果及心脏功能；方法：对13例在心内科住院的扩张型心肌病、缺血性心肌病、心动过速性心肌病所致心力衰竭的患者，男9侈4，女4侈4，年龄36岁～75岁(平均58．61岁)，心功能均在Ⅲ级～Ⅳ级(NYHA)，均有置入起搏器的适应证。术中通过Swan—ganz漂浮导管对右心室内不同部位起搏10分钟后测各部位的急性血液动力学改变，然后置入右心室双部位起搏器(右室流出道应用主动固定电极)。术后应用心电图、超声心动图观察右心室双部位起搏的血液动力学效果；结果：全组13例患者术中检查及置入右心室双部位起搏器均获成功。测得右心室流出道起搏(RV—OT)和右室心尖部(RVA) 右室流出道(RVOT)起搏时各参数均较单纯右室心尖部(RVA)为好。置入心脏起搏器后观察射血分数从0．31提高至0．39，左室充盈时间延长，二尖瓣返流量减少，心脏缩小，心脏功能平均提高Ⅱ级。其中一例心功能由Ⅳ级提高至I级～Ⅱ级；结论：初步血液动力学观察提示，右心室双部位起搏能改善充血性心力衰竭患者的心功能。     

Impact of Retrograde Cerebral Perfusion on Ascending Aortic and Arch Aneurysm Repair

Purpose. The effect of retrograde cerebral perfusion on the incidence of stroke and death among patients undergoing repair of aneurysms of the ascending aorta and transverse arch was determined.

Material and Methods. Between January 1991 and March 1995, 161 patients were operated on for aneurysms of the ascending aorta and transverse arch. Thirty-three of the patients (20%) had an aneurysm of the ascending aorta only and 128 (80%) had aneurysms of both the ascending aorta and the transverse arch. All the patients underwent cardiopulmonary bypass, profound hypothermia, and circulatory arrest, and 120 (74%) also underwent retrograde cerebral perfusion. Median pump time was 143 minutes (range, 21 to 461 minutes). Median circulatory arrest time was 42 minutes (range, 8 to 111 minutes), and median myocardial ischemic time was 71 minutes (range, 14 to 306 minutes).

Results. The overall 30-day mortality rate was 6% (9 patients) and the incidence of stroke was 4% (7 patients). The use of retrograde cerebral perfusion demonstrated a protective effect against stroke (3 of 120 patients, or 3%) compared with no retrograde cerebral perfusion (4 of 41 patients, or 9%; odds ratio, 0.24; confidence interval, 0.06 to 0.99; p < 0.049). This was most significant in patients more than 70 years of age; none of the 36 elderly patients who received retrograde cerebral perfusion had a stroke, compared with 3 of the 13 (23%) who did not (p < 0.003). Only pump time was associated with an increased risk of stroke (odds ratio, 1.01; 95% confidence interval, 1.00 to 1.02; p < 0.005). Pump time also was associated with increased mortality (odds ratio, 1.01; 95% confidence interval, 1.00 to 1.02; p < 0.008).

Conclusion. Retrograde cerebral perfusion decreased the incidence of stroke in patients undergoing repair of aneurysms of the ascending aorta and transverse arch.     

Milk consumption and prevalence of coronary heart disease in men and women from the Scottish Heart Health Study

This report uses cross-sectional results from the Scottish Heart Health Study to investigate whether milk consumption has an independent effect on the prevalence of coronary heart disease. Milk consumption was assessed by questionnaire in men and women aged 40–59 years (n = 10359) who participated in a survey of risk factors for coronary heart disease between 1984 and 1986. Odds ratios for coronary heart disease were calculated according to volume and type of milk consumed for subjects with and without symptoms of coronary heart disease. Statistical adjustment was made for the classicial risk factors.
A higher percentage of men and women with diagnosed coronary heart disease (CHD) usually consume low-fat milk, compared with asymptomatic controls. Odds ratios for having undiagnosed heart disease did not differ significantly with volume or type of milk. However, the odds ratios for having diagnosed heart disease were lower in the moderate (0.5–1 pint/d) milk consumption group. Patterns of milk consumption in patients diagnosed as having CHD are likely to be confounded by dietary changes post-diagnosis. Milk consumption appears to have little independent effect on the prevalence of coronary heart disease in this Scottish population.     

Extension of the “Elephant Trunk” Technique in Complex Aortic Pathology: The “Bidirectional” Option

Background. The “elephant trunk” technique, using a free-floating vascular prosthesis, was originally described to facilitate a subsequent operation on the downstream aorta. We developed an additional refinement of this technique, called the “bidirectional elephant trunk.” This option may represent an interesting tool in more complex aortic operations, especially when the descending aorta has to be replaced first in patients with concomitant pathology of the ascending aorta or of the aortic arch.

Methods. The initial operation is performed through a left thoracotomy. The proximal elephant trunk is created by invaginating the future aortic arch graft into the descending aortic graft. The proximal anastomosis between the doubled graft and the proximal descending aorta is performed first. During construction of the distal anastomosis, a distal elephant trunk may be inserted likewise. If the aortic arch and ascending aorta have to be replaced later, this second step is performed through a median sternotomy. The free-floating arch graft is pulled out of the proximal descending aorta with a nerve hook, unfolded, and used for total arch replacement.

Results. This technique was used successfully in 3 patients without mortality. No major complications were observed excepted persistent hoarseness in a patient with preoperative paresis of the recurrent nerve. No perfusion problems due to the unfolding of the free-floating graft occurred during the second operation.

Conclusions. The bidirectional elephant trunk technique is an interesting option that may be suitable for patients presenting with a complex pathology of the whole thoracic aorta when the descending segment has to be replaced first.     

An uncommon cause of acute right ventricular failure and high mixed venous oxygen saturation

Ruptured sinus of Valsalva aneurysms are rare. We report a case in which the usual clinical manifestations were not present and the patient was initially treated as an acute pulmonary embolus. Despite three negative echocardiograms an intra-cardiac shunt was suspected because of a persistently elevated mixed venous oxygen saturation. Cardiac catheterisation confirmed the diagnosis. Surgical repair was performed and post operative recovery was uneventful.     

先天性心脏病患儿肺动脉,上腔静脉血一氧化氮含量检测及意义

目的:探讨一氧化氮(NO)与先天性心脏病(CHD)引起的肺动脉高压(PH)发病间的关系。方法:应用NO试剂盒检测了CHD患儿肺动脉及上腔静脉血浆中NO含量。结果;(1)伴PH组肺动脉血浆NO含量明显高于不伴肺动脉高压组(37.58±9.99μmol/L:19.03±15.25μmol/L,P<0.01);(2)在PH组中,肺动脉血浆NO含量明显高于上腔静脉血(P<0.01);而不伴PH组,肺动脉和上腔静脉血浆NO含量无显著性差异(P>0.05)。结论:(1)伴PH的先心患儿肺动脉血浆NO含量升高;(2)NO可能介入了CHD引起的PH发病过程。     

原发性高血压病在平衡法核素心血池显像中的表现(与超声心动图及心机械图比较)

用44例原发性高血压(EH)患者及15例健康人对照组(N)的平衡法心血池显像(MGBP)心功能参数,对比分析了EH组多普勒超声心动图(UCG)及心机械图(MCG)的心脏检测指标.结果示,MGBP检测中 EH 组的左室高峰充盈率(PFR)、右室射血分数(RVEF)、局部射血分数_4(EF_4)及局部轴缩短率_4(RS_4)明显低于对照组(P<0.05～0.01).反映左室舒张功能的PFR与E/A峰比值(UCG)之间呈正相关(r=0.44,P<0.05),PFR与a/Eo(MCG)之间呈负相关(r=-0.87 P<0.01),PFR与左房内径(UCG)之间呈负相关(r=-0.48 P<0.05),反映左室间隔部位改变的EF_4,RS_4与室间隔厚度(UCG)均呈负相关(r=-0.3 P<0.05,;γ=-0.47 P<0.05).