Ala601-Thr type dysplasminogenaemia genetically diagnosed in patients with retinochoroidal vascular disorders

Dysplasminogenaemia has been reported in patients with retinochoroidal vascular disorders. The precise genetic defects of these cases, however, remain unclear because of the limitations of conventional diagnostic techniques. In this study, three patients with these diseases were investigated at the DNA level for the first time to define the molecular bases of these disorders. Polymerase chain reaction–restriction fragment length polymorphism analysis revealed that all three cases carried the same Ala601-Thr mutation. This defect may also play a role in the pathogenesis of circulation disorders in small local vessels because of reduced fibrinolytic activity due to decreased functional plasminogen levels.     

Arm exercise testing for coronary artery disease in patients with peripheral vascular disease

We evaluated 74 peripheral vascular disease (PVD) patients (54 men, age 61 +/- 7 years and 17 women, age 63 +/- 7 years) for potential coronary heart disease (CAD) using an arm exercise test (AET) protocol. All patients performed upright two-arm cranking using discontinuous stages of 2 minutes of exercise separated by 2 minutes of rest. Exercise intensity was increased by +100 or 200 kpm (kilopond meters) with each stage. ECG was monitored continuously and blood pressure and 12-lead ECG tracings were obtained at the end of each exercise stage. All patients reached an endpoint of subjective exhaustion. Men achieved 91 +/- 14% of age-predicted heart rate at 597 +/- 167 kpm, while women achieved 86 +/- 14% of age-predicted heart rate at 335 +/- 117 kpm. Ischemic ECG responses (+AET) defined as new or additional ST depression greater than 1.0 mm X 80 ms, occurred in 35 men (65%) and 7 women (42%). Coronary angiography was performed in a subset of 22 patients (15 males and 7 females). CAD (greater than 70% stenosis) was found in 11 of 12 men and 4 of 5 women who showed positive or strongly positive AET responses (overall predictive value for AET = 88%). We conclude that arm exercise stress testing is safely performed in PVD patients who cannot complete treadmill exercise. In this limited series of PVD patients, the predictive value of a +AET response for diagnosis of CAD is similar to established values for treadmill exercise.     

不同剂量辛伐他汀早期干预对急性冠状动脉综合征患者血清C反应蛋白的影响

目的观察不同剂量辛伐他汀早期干预对急性冠状动脉综合征(ACS)患者血清高敏C反应蛋白(hs-CRP)水平的影响及调脂作用与安全性。方法75例ACS患者随机分为三组,A组为优化药物治疗,B组为优化药物治疗加辛伐他汀20mg/d,C组为优化药物治疗加辛伐他汀40mg/d,均治疗4周,健康对照组不予治疗。分别于用药前及疗程结束后查hs-CRP及血脂水平,同时观察用药安全性。结果(1)ACS患者hs-CRP、总胆固醇(TC)、低密度脂蛋白胆固醇(LDL-C)、三酰甘油(TG)含量显著高于健康对照组(P<0.01)。(2)辛伐他汀20mg与40mg治疗4周后,均能显著降低hs-CRP、TC、LDL-C及TG水平(P均<0.01),其中40mg剂量组的疗效明显优于20mg剂量组。结论ACS患者hs-CRP显著升高,存在明显的炎症反应,早期大剂量辛伐他汀调脂干预,能安全更有效地抑制此类炎症反应及脂质过氧化损伤,且呈剂量依赖性。     

Assessment of myocardial perfusion with thallium-201 scintigraphy in exercise-induced left bundle branch block: diagnostic value and clinical significance.

Myocardial perfusion scintigraphy with thallium-201 was performed in 33 subjects (mean age 45 years, range 28-61) with exercise-induced, rate-dependent left bundle branch block (LBBB) in order to assess both the value of Thallium-201 myocardial imaging for the diagnosis of coronary artery disease (CAD) and the pathogenesis (ischaemic or not) of the conduction defect. Of the 33 patients evaluated, 16 had chest pain suggestive of CAD and 17 were asymptomatic. None had a history of prior myocardial infarction or clinical and echocardiographic signs of heart disease. LBBB appeared at a heart rate ranging from 70 to 160 b.min-1. Eighteen patients showed repolarization abnormalities (ST segment depression with deep inverted T waves) compatible with ischaemia, after QRS normalization. Thallium-201 myocardial uptake was normal in 12 subjects; in the remaining 21, reversible Thallium-201 defects were demonstrated in the septum (18 patients), septum and apex (2), and septum and infero-apical wall (1). No patient had irreversible defects and all had normal coronary angiography, with negative ergonovine tests for coronary artery spasm. The patients were followed up for a mean of 43 months (range 16-80). One patient died from sudden death, but no cardiac event occurred in the other patients. In conclusion, exercise Thallium-201 myocardial scintigraphy showed a high prevalence (64%) of reversible perfusion defects in a group of patients with exercise-induced LBBB without any evidence of CAD at angiography or coronary spasm at ergonovine test. Moreover, follow-up showed a relatively low rate of major cardiac events.     

Distensibility of the ascending aorta: comparison of invasive and non-invasive techniques in healthy men and in men with coronary artery disease

Distensibility of the ascending aorta, measured non-invasively,was compared with values obtained by invasive techniques in46 males (30 patients with coronary artery disease and 16 age-matchednormal subjects). Aortic diameters were measured at a level3 cm above the aortic valve using both echocardiographic andangiographic techniques. Aortic distensibility was calculatedfrom the aortic diameters and aortic pressure or brachial arterypressure using the formula: 2 x (change in aortic diameter)/(diastolic aortic diameter) x (change in aortic pressure).Distensibility of the ascending aorta determined non-invasivelywas closely related to that obtained by direct measurements(r = 0.949, P<0.001). Patients with coronary artery diseasehad similar pressures, but markedly lower distensibility thannormal subjects, as shown by both invasive and non-invasivetechniques. The results indicate that aortic distensibilityin patients with coronary artery disease can be obtained non-invasivelywith a high degree of accuracy.     

Supernumerary right coronary artery

A rare case of a patient with supernumerary right coronary artery in whom the two vessels arose from the right coronary sinus from two separate ostia adjacent to each other is presented. The smaller vessel gave off the sinoatrial nodal branch and the posterior descending artery whereas the larger one gave off the conus branch, the right ventricular branches, and continued as acute marginal branch. This is the first case report in the English literature.     

老年冠心病患者脂蛋白谱剖析

目的探讨老年冠心病患者的脂蛋白谱特点。方法以诊断明确的老年男性冠心病１４３例为观察对象，以年龄与生活水平相匹配的健康老年男性１４３名为对照，两组中均排除与脂代谢有关的其它疾病。以同一份血清用优选方法作１４项检查，包括总胆固醇（ＴＣ），甘油三酯（ＴＧ），高密度脂蛋白胆固醇及其亚类（ＨＤＬ－Ｃ、ＨＤＬ２－Ｃ、ＨＤＬ３－Ｃ），低密度脂蛋白胆固醇（ＬＤＬ－Ｃ），脂蛋白（ａ）〔Ｌｐ（ａ）〕，载脂蛋白（ａｐｏ）ＡⅠ、ＡⅡ、Ｂ、ＣⅠ、ＣⅡ、ＣⅢ和Ｅ。结果除ａｐｏＣⅠ、ＣⅢ两项外，其它１２项均值在冠心病组与对照组之间的差异均有显著性。逐步回归分析中顺次选入ａｐｏＡⅠ、ＬＤＬ－Ｃ与ＴＧ３项为优选指标，相关分析示Ｌｐ（ａ）是一项独立变量。结论在ＴＣ水平接近正常时，老年冠心病组最突出的改变是代表ＨＤＬ的５项参数均明显低下，其中以ａｐｏＡⅠ为最明显。临床上选用检验指标仍应以ＴＣ、ＴＧ、ＨＤＬ－Ｃ和ＬＤＬ－Ｃ为主，如果采用ａｐｏＡⅠ、Ｂ及Ｌｐ（ａ）测定，必须注意所用商品试剂的质量。     

New 3-Dimensional Volumetric Ultrasound Method for Accurate Quantification of Atherosclerotic Plaque Volume

BackgroundCarotid and femoral plaque burden is a recognized biomarker of cardiovascular disease risk. A new electronic-sweep 3-dimensional (3D)–matrix transducer method can improve the functionality and image quality of vascular ultrasound atherosclerosis imaging.ObjectivesThis study aimed to validate this method for plaque volume measurement in early and intermediate–advanced plaques in the carotid and femoral territories.MethodsPlaque volumes were measured ex vivo in pig carotid and femoral artery specimens by 3-dimensional vascular ultrasound (3DVUS) using a 3D-matrix (electronic-sweep) transducer and its associated 3D plaque quantification software, and were compared with gold-standard histology. To test the clinical feasibility and accuracy of the 3D-matrix transducer, an experiment was conducted in intermediate–high risk individuals with carotid and femoral atherosclerosis. The results were compared with those obtained using the previously validated mechanical-sweep 3D transducer and established 2-dimensional (2D)–based plaque quantification software.ResultsIn the ex vivo study, the authors assessed 19 atherosclerotic plaques (plaque volume, 0.76 µL-56.30 μL), finding strong agreement between measurements with the 3D-matrix transducer and the histological gold-standard (intraclass correlation coefficient [ICC]: 0.992; [95% CI: 0.978-0.997]). In the clinical analysis of 20 patients (mean age 74.6 ± 4.45 years; 40% men), the authors found 64 (36 carotid and 28 femoral) of 80 scanned territories with atherosclerosis (measured atherosclerotic volume, 10 μL-859 μL). There was strong agreement between measurements made from electronic-sweep and mechanical-sweep 3DVUS transducers (ICC: 0.997 [95% CI: 0.995-0.998]). Agreement was also high between plaque volumes estimated by the 2D and 3D plaque quantification software applications (ICC: 0.999 [95% CI: 0.998-0.999]). Analysis time was significantly shorter with the 3D plaque quantification software than with the 2D multislice approach with a mean time reduction of 46%.Conclusions3DVUS using new matrix transducer technology, together with improved 3D plaque quantification software, simplifies the accurate volume measurement of early (small) and intermediate–advanced plaques located in carotid and femoral arteries.     

Coronary artery stenting for acute closure complicating primary angioplasty for acute myocardial infarction

We report a case of progressive right coronary artery dissection complicating direct angioplasty for an acute inferior myocardial infarct, with successful bail-out stenting of the affected vessel.     

The applicability of the signal averaging technique in clinical cardiology

Summary: Since 1963 the signal averaging technique has been applied to improve the signal to noise ratio in highly amplified EKG registrations. Based on the experiences from the literature and the authors own laboratory, the applications of the signal averaging technique in clinical cardiology are reviewed: extraction and analysis of the fetal EKG and P-wave variations, His bundle electro-grams from the body surface (recovery rate 33–100% of cases), ventricular delayed depolarizations within the ST segment of the surface EKG (recovery rate, 40–90% of cases, depending on patient groups investigated), preatrial activity (sinus nodal potentials) from intra-cardiac (recovery rate, 80–90% of individuals), or surface EKGs (recovery rate, 60% of patients), analysis of frequency components of surface EKG-QRS complexes in patients with previous myocardial infarctions, and detection of low amplitude diastolic signals from surface phonocardiogram (recovery rate, 80% of cases). At present, advantages and limitations of the signal averaging technique may be appraised as follows: (1) sinus nodal potentials: S-A conduction times may be more reliable than those obtained by the extra-stimulus technique, since with averaging they are recorded during undisturbed sinus rhythm; direct recordings of changing S-A blocks may be impossible due to the summation process; validation of sinus nodal potentials in man necessary, (2) A-V nodal potentials: demonstration of true A-V nodal rhythm rather than His bundle rhythm; possibly direct identification of abnormal pathways in A-V nodal tachycardias; direct recordings of single A-V nodal blocks impossible due to summation process; (3) surface His bundle potentials: follow-up or screening of patients with A-V nodal and particularly His-Pur-kinje-system blocks; monitoring of antiarrhythmic drug therapy; atrial overlap in one-third of cases; direct identification of higher degree A-V nodal blocks impossible due to summation process (future developments may overcome this problem); (4) ventricular delayed depolarizations: possible identification of patients at high risk of sudden cardiac death; follow-up of therapeutic measures like antiarrhythmic drug therapy or cardiac surgery (bypass grafting, aneurysmectomy); validation of delayed depolarizations from body surface by direct intracardiac and/or epicardial mapping necessary.