View ordering for magnetization prepared steady state free precession acquisition: application in contrast-enhanced MR angiography.

Magnetization prepared segmented acquisition requires a view order that maximizes signal contrast during the acquisition of the central portion of k-space. Steady state free precession (SSFP) acquisition further requires a view order that minimizes changes in phase-encoding gradients from one repetition to the next in order to minimize eddy current artifacts. In this article, optimal view ordering schemes satisfying these two requirements are formulated and applied to inversion prepared 3D SSFP contrast-enhanced MR angiography (MRA). Experiments on phantoms and pigs demonstrated improved background suppression and reduced image artifacts.     

冠状动脉造影正常的急性心肌梗死临床分析

目的对比观察急性心肌梗死(AMI)冠脉造影正常和异常患者的临床表现.方法同期144例AMI患者,于发病12h内行尿激酶溶栓,并于心梗后7～14d内行经皮冠状动脉造影术,梗死相关动脉(IRA)再通且无冠脉病变者为冠脉正常组,再通且有冠脉病变及PTC成功者为冠脉异常组.记录二组患者易患因素,观察ST段抬高总和及90min回落程度,比较二组住院期间心脏事件发生率,并于出院前行超声心动图检查.结果144例患者中冠脉正常组10例,冠脉异常组134例,前者较后者年龄轻,男性,吸烟等诱因多见;造影时TMI 3级多见;ST段抬高总和于90min回落明显(P＜0.05);住院期间心脏事件发生率明显降低(P＜0.05);出院前超声心动图提示左室射血分数较高(P＜0.05).结论AMI冠脉造影正常者相对年龄轻,吸烟诱因多,住院期间心功能和临床预后好.     

急性冠脉综合征中妊娠相关蛋白-A与斑块不稳定性

目的探讨妊娠相关蛋白-A(PAPP-A)在急性冠脉综合征(ACS)中的变化及其与斑块不稳定性的关系。方法26例冠脉正常者作为对照组,稳定性心绞痛(SA)组22例,ACS组40例,包括不稳定性心绞痛(UA)20例、急性心肌梗死(AMI)20例。定量检测外周血PAPP-A、C-反应蛋白(CRP)、肌酸激酶MB同工酶(CK-MB)。对所有冠脉造影显示狭窄≥30%的病变进行影像学分析。结果ACS中PAPP-A含量(13·19±4·04)mIU/L明显高于SA(5·47±3·00)mIU/L(P<0·01)及对照组(5·09±2·19)mIU/L(P<0·01);并且与CRP(r=0·62P<0·01)、复杂性狭窄的数量(r=0·45P<0·05)有显著的正相关。结论PAPP-A在ACS患者外周血中明显升高,可能与斑块的不稳定性有关,对ACS的危险度分层可能具有一定的价值。     

Bilateral aberrant cervical internal carotid arteries

Summary A patient with symptomatic bilateral aberrant cervical internal carotid arteries, demonstrated on CT and MRI, is described.     

Dual origin of the left circumflex coronary artery: A case report

We describe a patient with two separate vessels having different origins supplying the circumflex coronary artery distribution. This represents a previously undescribed coronary artery anomaly.     

Probe™, a balloon wire: Initial experience

Coronary angioplasty is unsuccessful in <3–5% of cases because the balloon catheter fails to follow a guidewire that has traversed a lesion. Between June 1986 and August 1987, 31 lesions were unable to be crossed with at least two standard angioplasty catheters. Finally, a 2.0-mm-diameter Hartzler LPS (ACS) was utilized and successfully crossed and dilated 16 out of 31 lesions (52%). In the remaining 15 lesions, the Probe^TM (USCI) 2.0 mm diameter × 1.5 cm long balloon wire was able to cross the lesions in 13 (82%) and successfully dilated 12. In one case, lesion rigidity prevented the balloon from expanding at 14 atm. A right coronary artery lesion was attempted in 11 cases, and a left anterior descending and circumflex artery lesion in two patients each. No complications were encountered. In seven out of 12 successful Probe^TM cases, a larger balloon catheter was used to further dilate the artery. This new balloon wire has increased our success rate in severe stenoses and in tortuous vessels with severe distal lesions, in which presently available angioplasty equipment has failed.     

妊娠相关血浆蛋白A水平与不稳定心绞痛患者冠状动脉狭窄病变形态的关系

[目的]探讨不稳定型心绞痛患者妊娠相关血浆蛋白(PAPP-A)水平与高敏C-反应蛋白(hs-CRP)及动脉粥样硬化斑块稳定性的关系.[方法]不稳定型心绞痛组患者42例,稳定型心绞痛组38例.冠状动脉造影前检测PAPP-A和hs-CRP,根据造影结果将冠状动脉病变分为复杂狭窄和光滑狭窄.[结果]稳定型心绞痛组有28例(74%)患者至少有1支血管狭窄≥70%,多于不稳定型心绞痛组的24例(57%),P＜0.05;不稳定型心绞痛组中33例(79%)有1处以上的复杂狭窄,多于稳定型心绞痛组(22例,58%,P＜0.05);PAPP-A与hs-CRP正相关(r=0.44,P＜0.001);不稳定型心绞痛组与稳定型心绞痛组相比,hs-CRP(4.40 mg/L±0.003 mg/L vs 0.48 mg/L±0.016mg/L,P＜0.001)和PAPP-A(18.40×10-3 U/L±0.002×10-3U/Lvs 7.79×10-3 U/L±0.001×10-3 U/L,P＜0.001),差异均有统计学意义;两组中有复杂狭窄者的PAPP-A和hs-CRP水平显著高于无复杂狭窄者.[结论]PAPP-A可作为评估冠状动脉斑块稳定性的血清学指标之一.     

A Decrease in Pulmonary Vein Diameter After Radiofrequency Ablation Predicts the Development of Severe Stenosis

A decrease in ostial pulmonary vein (PV) diameter was observed in patients on the day after radiofrequency ablation of atrial fibrillation (AF). This study examined whether a relative reduction in PV diameter on day 1 (RRPVD1) after the procedure predicts the late development of severe PV stenosis (PVS). The study included 104 consecutive patients (mean age = 55 years, range 46–61, 34 women) with drug refractory AF. Pulmonary vein diameter was measured using MR angiography (MRA) on the day before and on day 1 after the ablation procedure. The MRA was repeated every 3 months after the procedure. Severe PVS was defined as a >70% diameter reduction from the initial ostial diameter. The cut-off of RRPVD1 was prespecified as 25% decrease in initial diameter. The data are presented as medians and interquartile range. A total of 357 PV were treated. The RRPVD1 was 0.0% (0.0–11.1%). Severe PVS was found in 18 PV during a follow-up of 12 months (range 6–13). The log-rank analysis confirmed a strong association between a RRPVD1 ≥25% and the development of PVS (hazard ratio: 7.1; 95% confidence interval 3.8–13.5, P < 0.0001). By multivariate Cox regression model, after adjustment of procedure variables, RRPVD1 was the strongest predictor of development of severe PVS. RRPVD1 ≥25% was a strong independent predictor of development of severe PVS.     

Effect of morphological abnormalities on blood retinal barrier permeability in diabetic retinopathy

The morphological base for the impaired function of the blood retinal barrier was studied in 50 eyes of 10 insulin dependent and 21 non-insulin dependent patients with various levels of diabetic retinopathy. The permeability of the blood retinal barrier (P_BRB) was determined by vitreous fluorophotometry with correction for autofluorescence, lenstransmission and non-protein bound plasma fluorescein concentration. Morphological abnormalities of diabetic retinopathy assessed by fundus photography and fluorescein angiography were individually scored on a decimal scale and related to the P_BRB by multiple regression analysis. The P_brb was not correlated to morphological abnormalities of non-proliferative retinopathy [(1) microaneurysms, (2) hard exudates, (3) soft exudates, (4) intraretinal hemorrhages, (5) fluorescein leakage, and (6) capillary closure, p > 0.3]. The P_BRB was correlated to morphological abnormalities of (pre)proliferative retinopathy [(1) intraretinal microvascular abnormalities (S_irma) and (2) new vessels (S_neo): p_brb = A – B.S_IRMA – C.S_neo with P_BRB in nm/sec, A = 1.5 ± 0.5, B = 0.9 ± 0.2 and C = 1.7 ± 0.4, R² = 0.65, p < 0.0001]. It can be concluded that the increased blood retinal barrier permeability in diabetic patients is mainly due to (pre)proliferative abnormalities and not to non-proliferative abnormalities.     

多层螺旋CT冠脉成像的临床应用

目的旨在评价多层螺旋CT(MSCT)在冠状动脉疾病诊断中的作用。方法57例患者,按心率≤60次/min、60～70次/min、>71次/min分成3组,行冠脉MSCT造影(MSCTA),将数据在回顾性心电门控下行最大密度投影(MIP)、容积重建(VR)和多平面重建(MPR),观察其对冠状动脉的显示,其中11例与选择性冠状动脉造影(SCA)对照。结果心率≤70次/min患者CT图像质量明显优于心率>70次/min组(P<0.001)。11例与相应的SCA比较,MSCTA诊断50%以上狭窄的敏感度、特异度、阴性预测值和准确度分别为88.9%、71.4%、86.7%和83.3%。结论MSCT能显示冠状动脉钙化和狭窄、进行冠脉支架术后评价。