右心声学造影实时三维超声心动图测量犬右室心搏量

目的:评价实时三维超声心动图(RT3DE)结合右心声学造影技术测量右室心搏量的准确性。方法:应用实时三维超声诊断仪对15只健康杂种犬分别采集无造影、经静脉右心造影并同步经左心耳左心造影的心尖长轴全容积三维数据库,脱机后应用容积分析软件进行后处理分析,分别用2、4、8、16平面法勾画右室内膜面,测量右室舒张末期容积(RVEDV)与收缩末期容积(RVESV),计算右室每搏量(RVSV),同时用16平面法测量左室舒张末期容积(LVEDV)与收缩末期容积(LVESV),计算左室每搏量(LVSV),进行左右每搏量对照分析。结果:运用右心声学造影后,右室内膜面显示更为清晰,可重复性增加。RT3DE有造影2平面、4平面、8平面以及16平面法测得的RVSV与16平面法测得的LVSV之间的相关性分别为0.701,0.800,0.894,0.980。无造影RT3DE上2平面、4平面、8平面以及16平面法测得的RVSV与16平面法测得的LVSV之间的相关性分别为0.690,0.758,0.852,0.904。相同平面法比较显示RT3DE有造影的相关性都要高于RT3DE无造影。LVSV与RT3DE心尖长轴2平面法测量有造影的RVSV比较有显著性差异(P<0.05),与4、8和16平面法比较无显著性差异(P>0.05);而与2和4平面法测量无造影的RVSV比较有显著性差异(P<0.05),与8和16平面法比较无显著性差异(P>0.05)。结论:右心声学造影技术可以提高实时三维超声心动图测量右室心搏量的准确性。     

Angiocardiographic Pressure Volume Loops in the Analysis of Right Ventricular Function after Repair of Tetralogy of Fallot

Objective: The objective of the study was to estimate the capacity of pressure volume (PV) loop analysis to assess right ventricular (RV) function after Fallot (TOF) repair.Patients: Fifty six patients were examined after TOF repair. PV loops were constructed from RV angiocardiography and simultaneous pressure measurement. Patients were divided in three groups according to RV size and pressure (Group I: normal RV size and pressure; group II: enlarged RV, near normal pressure; group III: normal RV size, elevated pressure).Main outcome measures: Systolic stroke work corrected for body surface area (W/BSA) and for RV enddiastolic volume (W/EDV), peak RV filling (PFR) and emptying rates (PER) corrected for RV stroke volume, cycle efficiency (CE), RV ejection fraction (RVEF).Results: W/BSA was significantly higher in group II than in group I (0.19 ± 0.05 vs. 0.11 ± 0.04 J/m², p < 0.001) and was similar between groups II and III (0.19 ± 0.05 vs. 0.17 ± 0.05 J/m² ; NS). W/EDV was similar in groups I and II (12.4 ± 5.4 vs. 12.4 ± 2.9 mmHg; NS). CE was smallest in group II. The difference was significant between groups II and III (0.62 ± 0.08 vs. 0.73 ± 0.09; p < 0.05). RVEF was negatively correlated to RV end systolic volume (RVESV) in the patients of groups I and II (r = −0.32, p < 0.05). A similar correlation was found between PFR and RVESV (r = −0.28, p < 0.05).Conclusions: Analysis of a single PV loop allows quantification of RV load after TOF repair. W/BSA is increased to the same extent under volume and pressure load. The lack of decrease in W/EDV in patients with enlarged RV indicates that RV is capable to perform adequate work in a wide range. RVESV is a useful measure for estimating RV function after TOF repair depicting parameters of systolic and diastolic RV function.     

碎裂QRS波在冠心病诊断中的临床意义

目的探讨心电图碎裂QRS（fQRS）波在冠心病诊断中的临床意义。方法选择性冠状动脉造影（CAG）诊断为冠心病的患者108例（冠心病组）,同期CAG阴性患者108例（对照组）,比较两组心电图fQRS波的发生率及fQRS波在心电图相对应心肌前壁、侧壁和下壁的分布情况。冠心病组患者分为前降支（LAD）和非LAD病变组、回旋支（LCX）和非LCX病变组和右冠状动脉（RCA）和非RCA病变组,比较与其对应心电图导联fQRS波的关系。结果冠心病组fQRS波发生率为66.7%（72/108）,显著高于对照组的24.1%（26/108）（χ^2=39.524,P〈0.01）。冠心病组Ⅱ、Ⅲ、aVF导联fQRS波的发生率为45.4%（49/108）,明显高于对照组的10.2%（11/108）（χ^2=33.323,P〈0.01）;冠心病组V1-V5导联和Ⅰ、aVL、V5、V6导联fQRS波的发生率分别为8.3%（9/108）和13.0%（14/108）,对照组为5.6%（6/108）和6.5%（7/108）,两组比较差异无统计学意义（χ2值分别为0.641,2.574,均P〉0.05）。在LAD和非LAD病变、LCX和非LCX病变和RCA和非RCA病变组患者中,相对应的V1-V5导联、Ⅰ、aVL、V5、V6导联和Ⅱ、Ⅲ、aVF导联fQRS波的发生率分别为8.1%（5/62）和8.7%（4/46）、20.0%（9/45）和7.9%（5/63）、46.6%（27/58）和44.0%（22/50）,两组间比较差异无统计学意义（χ^2值分别为0.010,3.386,0.071,均P〉0.05）。结论心电图fQRS波对冠心病诊断有预测价值,尤其是Ⅱ、Ⅲ、aVF导联fQRS波提示冠心病可能性大。但依据心电图上不同导联出现的fQRS波尚不能判断冠状动脉病变支。     

非青紫型先天性心脏病外周肺血管病变影像学方法比较

目的探讨无创性影像学诊断方法在非青紫型先天性心脏病(CHD)外周肺血管形态学上的诊断价值。方法对200例合并外周肺血管狭窄的非青紫型CHD患儿(其中164例合并外周肺血管狭窄,36例合并术后残存外周肺血管狭窄),在手术前或心导管造影(ACG)前行CT血管造影(CTA)和(或)磁共振成像血管造影(MRA)检查,分别测量外周肺血管狭窄处内径,并与手术或ACG实测值进行配对样本T检验。结果 ACG、CTA和MRA均能清晰显示外周肺血管及其分支形态学发育情况,CTA和MRA对外周肺血管内径的测量值与手术或ACG实测值相似。结论 CTA、MRA是无创性评估外周肺血管形态学发育情况的良好影像学诊断方法,可以取代有创性ACG检查。     

冠状动脉造影对比活动平板心电图负荷试验评价对冠心病的诊断价值

目的用冠状动脉造影(冠造)对比活动平板心电图负荷试验(平板运动)评价平板运动对冠心病的诊断价值.方法临床可疑冠心病,符合平板运动适应证98例,行18导联平静心电图、平板运动及冠造对比分析.结果 (1)平板运动与冠造对比98例平板运动属阳性者35例(35.7%),其中冠造有改变者25例(71.4%),其中有狭窄≥50%符合冠心病诊断的为18例(51.4%),属阴性者63例(64.3%),其中冠造有改变者21例(33.3%),两组对比有明显差异(P＜0.01).(2)平静心电图可疑心肌缺血78例(79.6%),其中冠造有改变者39例(50.0%),平静心电图正常者20例,其中冠造有改变者7例(35.0%).(3)35例阳性者平板运动终止后心电图异常出现时间与冠造对比运动结束后即刻～2min出现阳性者18例(51.4%),冠造有狭窄者13例(72.2%),其中双支及3支病变12例(92.3%),包括全闭2例;＞2min～4min阳性者9例(25.7%),冠造有改变者6例(66.7%);＞4min～6min阳性者6例(17.1%),冠造有改变者4例;＞6min～8min阳性者2例(5.70%),均为单支病变.各组病变程度比较有明显差异(P＜0.01).结论 (1)平板运动与冠造对比存在假阳性与假阴性分别为28.6%和33.3%,不能只凭平板运动肯定与否定冠心病.(2)平板运动结束后其阳性出现时间愈早,冠脉病变愈重而且双支及3支病变较多.     

Morphological and functional study of ischemic left ventricle after laser transmural revascularization

Ｍｏｒｐｈｏｌｏｇｉｃａｌａｎｄｆｕｎｃｔｉｏｎａｌｓｔｕｄｙｏｆｉｓｃｈｅｍｉｃｌｅｆｔｖｅｎｔｒｉｃｌｅａｆｔｅｒｌａｓｅｒｔｒａｎｓｍｕｒａｌｒｅｖａｓｃｕｌａｒｉｚａｔｉｏｎ￥ＧａｏＦａｂａｏ；ＨｕａｎｇＺｈｉｌａｎ；ＳｕｏＬｉｐｉｎｇ；Ｑｉ...     

16层CT冠状动脉造影的技术及影响图像质量的因素

目的探讨16层CT冠状动脉造影的成像技术及影响图像质量的因素。方法52例受检者按心率≤70次/min和>70次/min分为2组,分别行16层螺旋CT心电门控条件下冠状动脉造影,预览R-R间期0%～100%的21幅图像(间隔5%),选择显示左、右冠状动脉最清晰的一幅,应用原始数据重建该时相的薄层图像,再进行MIP、MPR、CPR、VR重建。2组图像质量均分为能用于冠状动脉评价和不能用于冠状动脉评价2类。结果16层CT冠状动脉成像的最佳重建时相多位于55%～65%R-R间期。心率≤70次/min组,有87%(301/346支)的图像可用于诊断,心率>70次/min组,有78.8%(134/170支)的图像可用于诊断。结论影响冠状动脉评价的因素主要有冠状动脉运动、冠状动脉钙化、心率波动等。     

A comparative study of five different techniques to reduce left ventricular dysfunction during endotracheal intubation

Thirty-five non-selected, consenting patients were studied during induction of anesthesia before coronary artery bypass grafting. Anesthesia was induced with diazepam, thiopentone and fentanyl, followed by pancuronium. Before induction, 200 MBq Tc 99 m - HSA was given i.v. and ejection fraction (EF) of the left ventricle was measured with a collimated single-crystal probe. The patients were allocated to five groups (seven patients in each) treated with: Group A: nitroglycerin i.v. bolus 4 micrograms x kg-1 given 30-60 s before laryngoscopy; Group B: nitroglycerin i.v. in continuous infusion, 1 micrograms x kg-1 x min-1 started before induction; Group C: two-stage topical anesthesia of the vallecula region and larynx with lidocain; Group D: a combination of nitroglycerin and topical anesthesia (as in Group B and C); and Group E: propranolol i.v. 0.01 mg x kg-1 given 5 min before intubation. All groups reacted in the same way during induction of anesthesia up to the point of laryngoscopy. End-diastolic volume and systemic arterial pressure decreased while cardiac index remained unchanged and EF increased. During laryngoscopy and intubation, however, differences between the groups were evident. Nitroglycerin i.v. as a bolus effectively prevented a reduction in EF and an increase in left ventricular volume. In addition to these beneficial hemodynamic effects, there was a moderate increase in heart rate and a reduction of stroke index. Continuous infusion of nitroglycerin and propranolol i.v. had no effect, since EF fell and left ventricular volume increased. Patients receiving topical anesthesia demonstrated a blunted response to endotracheal intubation with a moderate decrease in EF and an unchanged (Group C) or slightly increased (Group D) left ventricular volume.     

Editorial comment

The left ventriculograms of 113 patients, divided into seven groups, were reviewed for the detection of unopacified front (UOF) of blood entering the left ventricle (LV) during diastole. Normal UOF was detected in all the patients without left-sided valvular heart disease (regardless of the existence of coronary artery disease), constrictive pericarditis, aortic stenosis, and mitral regurgitation, although in the last group the UOF faded after several beats in 70% of cases. Only 5% of the patients with isolated mitral stenosis (MS) had an UOF, 75% had an abnormal UOF (< 60% of LV inflow tract), and 20% (with the greatest degree of MS) had only a dilution effect. A dilution effect was found in 62.5% of the patients with severe (?3°) aortic regurgitation (AR). An abnormal UOF is a sensitive and specific marker of significant MS. A dilution effect is indicative of either a significant MS or severe AR. © 1995 Wiley-Liss, Inc.