经皮冠状动脉成形术时冠状动脉内心电图变化

对３９例冠心病患者接受经皮冠状动脉（冠脉）成形术（ＰＴＣＡ）时的冠脉内心电图（ｉｃＥＣＧ）和常规心电图（ＥＣＧ）的ＳＴ段、Ｔ波、Ｒ波和Ｕ波变化作了对照分析。结果表明，在左旋支ＰＴＣＡ时，ｉｃＥＣＧ的ＳＴ段改变的发生率明显高于常规ＥＣＧ（９７％比３３％，Ｐ＜０．０１）。ｉｃＥＣＧ的ＳＴ段和Ｔ波开始改变的时间和变动幅度均比常规ＥＣＧ更迅速、更明显。倒置Ｕ波的发生率亦高于常规ＥＣＧ。提示在ＰＴＣＡ时ｉｃＥＣＧ的变化比常规ＥＣＧ更敏感、更迅速。     

急性心肌梗塞急诊PTCA后ST段改变及其临床意义

目的　对９５ 例急性心肌梗塞（ＡＭＩ）患者急诊经皮冠状动脉腔内成形术（ＰＴＣＡ）后３０ 分钟体表心电图ＳＴ 段改变进行分析，探讨此时ＳＴ 段改变与ＰＴＣＡ 效果、心肌损害程度及心功能预后的关系。方法　根据ＳＴ 段改变分三组。组Ⅰ：ＳＴ 段明显下降（≥５０％ ）组５５ 例，组Ⅱ：ＳＴ 段下降（＜ ５０％ ）组３２ 例，组Ⅲ：ＳＴ 段无变化或抬高者组８ 例。测定术后肌酸激酶（ＣＫ）的变化，同时测定术前及术后心功能。结果　组Ⅰ与组Ⅱ为ＰＴＣＡ 成功者，术后组ⅡＣＫ 明显高于组Ⅰ。术后４～６ 周组Ⅱ射血分数（ＥＦ％ ）明显低于组Ⅰ。结论　急性心肌梗塞患者ＰＴＣＡ 术后３０ 分钟体表心电图ＳＴ 段的改变能间接反映ＰＴ－ＣＡ 疗效。较准确早期了解心肌细胞灌注情况并判定预后     

冠状动脉内心电图对冠状动脉腔内球囊扩张时缺…

通过对１５例经皮冠状动脉（简称冠脉）腔内球囊成形术（ＰＴＣＡ）患者的冠脉内心电图（ＩＣ－ＥＣＧ）与体表心电图（Ｓ－ＥＣＧ）的对比分析，评价ＰＴＣＡ时的心肌缺血预适应。ＩＣ－ＥＣＧ、Ｓ－ＥＣＧ显示：①球囊第１次扩张时Ｓ段分别上抬２１．１±１５．３和３．３±１．９ｍｍ；第２次扩张时上抬１３．１ ９．６和２．３±１．２ｍｍ；第３次扩张时上抬７．７±７．２和１．９±１．２ｍｍ；第４次扩张时上抬４．５±３．     

缺血预适应在经皮冠状动脉腔内成形术中的应用

对２６例冠心病患者随机分为预适应组（１４例）和对照组（１２例），分别观察经皮冠状动脉腔内成形术（ＰＴＣＡ）中心绞痛及心电图变化和术后心绞痛及运动心电图。结果显示：预适应组术中心绞痛积分和ＳＴ段抬高幅度均显著低于对照组（均Ｐ＜０．０５），心绞痛及ＳＴ段抬高出现时间均显著迟于对照组（均Ｐ＜０．０５）。术后随访６个月，预适应组心绞痛及运动心电图阳性例数显著低于对照组（均Ｐ＜０．０５）。表明缺血预适应不但可以减轻ＰＴＣＡ中心肌缺血的程度，而且也能降低术后心肌缺血的复发。     

经皮腔内冠状动脉成形术前后血浆内皮素—1水平的动态观察

采用放射免疫分析法测定了１４例冠心病心绞痛患者经皮腔内冠状动脉成形术（ＰＴＣＡ）（８例）及单行冠状动脉造影术（ＣＡＧ）（６例）前后血浆内皮素—１（ＥＴ—ｌ）水平并与１０例正常人作对照观察。结果显示：ＣＡＧ及ＰＴＣＡ后对小时内血浆ＥＴ—１水平均未见显著升高（Ｐ＞０．０５）。提示，ＰＴＣＡ前后全身循环ＥＴ的血浆浓度改变不大。     

直接经皮冠状动脉腔内成形术与溶栓治疗急性心肌梗塞近期疗效分析

目的比较直接经皮冠状动脉腔内成形术（ＰＴＣＡ）与药物溶栓治疗急性心肌梗塞（ＡＭＩ）患者住院期间的临床效果。方法在１０９例ＡＭＩ患者中，４５例患者接受直接ＰＴＣＡ治疗，６４例患者接受药物溶栓治疗。结果溶栓组梗塞相关血管（ＩＲＡ）再通的患者有４８例，再通率为７５％；直接ＰＴＣＡ组ＩＲＡ成功开通的患者有４４例，成功率为９７．８％。住院期间左室射血分数（ＥＦ）溶栓组为５４．１±１３．２，直接ＰＴＣＡ组为６４．２±１０．１，差异有显著性（Ｐ＜０．０５）；病死率分别为６．３％和２．２％，两组间差异无显著性（Ｐ＞０．０５）。进一步分析溶栓再通组与直接ＰＴＣＡ成功组的临床疗效，前者因再闭塞或缺血发作行择期ＰＴＣＡ的比率明显高于直接ＰＴＣＡ组（２７．１％ｖｓ０；Ｐ＜０．０５），但直接ＰＴＣＡ组左室ＥＦ仍显著高于溶栓再通组（６４．８±９．８ｖｓ５５．９±１２．６Ｐ＜０．０５）。住院期间再发梗塞，心肌缺血事件和心力衰竭例数溶栓再通组都有增加的趋势，但差异无显著性（Ｐ＞０．０５）。结论直接ＰＴＣＡ与溶栓治疗ＡＭＩ患者，前者可使ＩＲＡ充分有效地开通，能更好地改善患者心功能     

心肌缺血预适应在PTCA中的临床价值

将１００例冠心病患者分为Ａ，Ｂ两组，Ａ组先行心肌缺血预适应症再行经皮冠状动脉球囊成形术（ＰＴＣＡ），Ｂ组仅行ＰＴＣＡ。结果显示，两组扩张效果相似，但Ａ组在ＰＴＣＡ中出现心绞痛，缺血型心电图ＳＴ段改变时间均比Ｂ组明显延迟且较轻，术中低血压，室速发生率较低（Ｐ〈０．０５），因此认为，ＰＴＣＡ中采用预适应方法对减少并发症和病死率有重要意义。     

经皮冠状动脉腔内成形术后冠状动脉再狭窄的外科治疗

目的：探讨经皮冠状动脉腔内成形术（ＰＴＣＡ）后冠状动脉再狭窄的治疗方法。方法分析２５例ＰＴＣＡ术后冠状动脉再狭窄接受冠状动脉旁路移植手术（ＣＡＢＧ）患的ＰＴＣＡ前后的临床资料。ＰＴＣＡ后心绞痛症状未缓解５例,术后２天至１７个月复发心绞痛２０例,平均再狭窄发生时间ＰＴＣＡ后４．６个月。一次ＰＴＣＡ后选择ＣＡＢＧ１９例,２次４例,３次２例。除ＰＴＣＡ或支架部位处发生再狭窄外,５例狭窄以冠状动脉病     

体表电位标测评定经皮冠状动脉腔内成形术疗效的价值

报告７例冠心病患者经皮冠状动脉腔内成形术（ＰＴＣＡ）前、后体表电位标测（ＢＳＰＭ）的变化。结果表明：ＰＴＣＡ后Ｔ波等电位异常形态明显改善或恢复正常，ＳＴ－Ｔ标测计算指标和ＳＴ－Ｔ极小值位置ＰＴＣＡ前、后有明显改变。提示ＢＳＰＭ可用于ＰＴＣＡ近期疗效的无创伤性评定。     

冠状动脉内超声显像与造影对冠状动脉病变检出的比较

目的研究冠状动脉造影（ＣＡＧ）正常者的冠状动脉内超声显像（ＩＣＵＳ）检查结果，结合临床表现及辅助检查，藉以提出ＩＣＵＳ检查的适应证。方法对连续４００例临床待诊或确诊为冠心病的患者行ＣＡＧ同时行ＩＣＵＳ检查。结果４００例患者中，１３５例ＣＡＧ正常者，而ＩＣＵＳ检查示：２８例正常，３８例冠状动脉内膜增厚，６９例有不同性质的斑块。分组分析，斑块组与非斑块组之间的冠心病高危因素比较，差异有显著性（Ｐ＜００５）。结论表明ＩＣＵＳ对冠状动脉病变的检出较ＣＡＧ敏感，认为ＣＡＧ检查结果正常者，若临床上心绞痛症状典型、年龄较大、血脂较高、吸烟及心电图有异常改变者，尤其是男性患者宜进一步行ＩＣＵＳ检查。     

直接经皮冠状动脉腔内成形术中冠状动脉内心电图判定存活心肌的价值

目的 应用99mTc-MIBI心肌断层显像(SPECT)评价冠状动脉内心电图(IC-ECG)判定急性心肌梗死(AMI)存活心肌的价值。方法 56例急性前壁心肌梗死患者，接受了直接经皮冠状动脉腔内成形术(PTCA)，梗死相关动脉前降支(LAD)达到TIMI3级血流后IC-ECG自PTCA导引导丝尾端引出作为参照基线，在进一步球囊扩张时IC-ECG ST段再次抬高大于0．2mV时认为具有判定梗死相关部位有存活心肌的意义。测定并比较急性期及恢复期左心室梗死相关区域节段性缩短率(LVSS)与射血分数(LVEF)，梗死区域存活心肌通过恢复早期静息与硝酸甘油介入两次99mTc-MIBI SPECT量化判定。结果 4l例病人(A组)行直接PTCA时IC-ECG ST段明显抬高，15例(B组)未出现相应变化，A组INSS、INEF。在恢复期均显著大于B组，两次99mTc-MIBISPECT显示，硝酸甘油介入后显像A组梗死缺损区面积明显减少，核素放射性计数百分比亦明显增加，B组则无明显改变，说明A组梗死区域有较多存活心肌，与IC-ECT ST段抬高意义一致。结论 直接PTCA过程中可通过球囊扩张时IC-ECG ST段抬高变化初步判定梗死相关区域的心肌活性。     

Value of the intracoronary electrocardiogram to monitor myocardial ischemia during percutaneous transluminal coronary angioplasty

To enhance detection of ischemia during percutaneous transluminal coronary angioplasty (PTCA), unipolar intracoronary electrocardiograms (ECGs) were recorded during PTCA in 25 patients from the tips of guidewires positioned distal to stenoses being dilated. Surface electrocardiographic leads chosen to reflect likely areas of reversible ischemia during PTCA were recorded simultaneously. In 21 of 29 stenoses dilated (72%), ST segment elevation and/or T wave peaking in intracoronary ECG appeared during balloon inflation and disappeared after deflation, accompanied by transient angina on 19 occasions. Two patients had transient ST segment elevation in intracoronary ECGs during PTCA without associated angina. ST changes in the surface ECG during PTCA were seen on only nine occasions (31%), always accompanied by ST segment elevation in the intracoronary ECG that appeared earlier and was of much greater magnitude. Five patients with prior myocardial infarction and aneurysm formation had fixed ST segment elevation in the intracoronary ECG unrelated to balloon inflation. Myocardial ischemia during PTCA can be detected easily with intracoronary ECGs and with greater sensitivity than that of the surface ECG. Furthermore, intracoronary ECGs may help to clarify the nature of chest pain during balloon inflation or during suspected complications.     

Use of intracoronary electrocardiography for detecting ST-T, QTc, and U wave changes during coronary balloon angioplasty

Intracoronary electrocardiography (IC-ECG) is a more sensitive method than surface ECG to detect electrical changes during percutaneous transluminal coronary angioplasty (PTCA). It also provides direct monitoring of ST-T segment, QTc intervals, and U-wave genesis during balloon inflation. These changes are reflective of myocardial ischemia. The authors studied the effect of transient myocardial ischemia on ST-T segment, QTc intervals, and U-wave appearance by comparing standard and perfusion balloon angioplasty. PTCA of left anterior descending artery was performed in 14 patients using the standard balloons and in 11 patients using the perfusion balloons. Patients with perfusion balloon angioplasty had less ST-T elevation (0.15 +/- 0.05 mV versus 1.04 +/- 0.19 mV, P < 0.001), less QTc-shortening intervals (0.01 +/- 0.02 seconds versus -0.05 +/- 0.04 seconds, P < 0.001), and less positive U waves (two versus nine). The authors concluded that balloon angioplasty with perfusion balloons is associated with less ischemia as reflected by ST-T, QTc-shortening intervals, and U-wave changes. There was more positive U-wave appearance with the standard balloon angioplasty, which implies more ischemia. In addition, QTc-shortening intervals are associated with the development of U waves during standard balloon angioplasty. These findings suggest that IC-ECG is a sensitive tool in detecting myocardial ischemia. IC-ECG may also help to clarify the nature of chest pain during PTCA in some patients. Like QT dispersion (QTd), QTc-shortening intervals and new U waves can have prognostic implications and additional studies are needed to define this role.     

The impact of autoperfusion on quantitative electrocardiographic parameters of ischemia severity, extent, and "burden" during salvage of elective coronary angioplasty

Long angioplasty inflations have been reported using an autoperfusion system that delivers oxygenated blood distal to the balloon segment. The safety and efficacy of this system has been demonstrated in anatomically selected patients. The clinical use, however, is frequently to stabilize intimal dissection in unselected patients. We reviewed 12-lead continuous electrocardiographic (ECG) recordings in 40 patients in whom prolonged salvage with autoperfusion was attempted. Sub-optimal results were stabilized in 36 of 40, while 4 patients had urgent bypass. The presence of ischemia, as > or = 100 uV ST elevation over the 12 lead ECG, and the total ST deviation over all leads over the entire inflation period (total ischemic "burden") were compared within each patient between the longest standard balloon and autoperfusion inflations. Median duration of inflation was 3.03 min. with balloon vs. 15.6 min. with autoperfusion (p < 0.00002). Of the 40 patients, 35 (87%) had ECG ischemia with balloon vs. 18 (45%) with autoperfusion (p < .00002). Median severity of peak ST deviation was 321 uV with balloon vs. 132 uV with autoperfusion (p = 0.0001). Median extent of ST elevation was 3 leads with balloon vs. 0 leads with autoperfusion (p = 0.0001). Median total ischemic burden was similar with balloon (1173 uVmin) and autoperfusion (1083 uVmin, NS) despite the fivefold longer inflation duration with autoperfusion. Thus, in patients selected by clinical necessity rather than optimal anatomy, severity and extent of ST elevation were significantly reduced, although not entirely eliminated, by autoperfusion.     

Optimal ECG monitoring during percutaneous transluminal coronary angioplasty of the left anterior descending artery

During percutaneous transluminal coronary angioplasty (PTCA) frontal ECG leads are routinely monitored. The detection of ST segment deviation during the procedure is important for decisions regarding guiding catheter seating and the timing of balloon inflation and deflation. ST segment deviation appears on intracoronary electrograms in the absence of changes on the surface ECG in many patients, while the reverse is true in some individuals. When a precordial lead is employed, V5 or V6 is most commonly selected. The surface ECG leads most sensitive for monitoring ischemia during left anterior descending angioplasty are not known. In nine lead surface ECGs recorded during balloon inflation, a small degree of ST segment elevation occurred in leads I, aVL, and V5. Lead V2 demonstrated an increase in ST displacement from 0.0 ± 0.03 mV to 0.29 ± 0.25 mV during coronary occlusion (p<0.01). We conclude that if V5 or V6 is used as a single precordial lead, surface ECG alterations are easily overlooked. During left anterior descending occlusion the most sensitive surface lead is V2. Optimal ECG monitoring during PTCA in some cases should involve surface lead V2 or the intracoronary lead.     

Attenuation of myocardial ischemia during coronary occlusion by ultrashort-acting beta adrenergic blockade.

To assess the effect of the ultrashort-acting beta blocker esmolol on ischemia induced by acute coronary occlusion, we studied 16 patients undergoing coronary angioplasty. Doppler echocardiography and ECG monitoring were performed continuously before, during, and after balloon occlusion in the drug-free state and during esmolol infusion. Fourteen of the 16 patients had ST segment elevation during balloon inflation. However, maximal ST segment elevation (2.1 +/- 1.5 mm vs 1.7 +/- 1.3 mm, p less than 0.001) and duration of ST segment elevation (68 +/- 20 seconds vs 54 +/- 19 seconds, p less than 0.05) were both significantly reduced during esmolol infusion. Furthermore, the decrease in ejection fraction seen during drug-free balloon occlusions was significantly blunted during esmolol infusion. In the baseline state ejection fraction decreased from 55% to 38% (p less than 0.05) during coronary occlusion compared with a decrease from 52% to 49% (p = NS) during esmolol infusion. In addition, esmolol appeared to delay the onset of segmental wall motion abnormalities after coronary occlusion, occurring at a mean of 40 seconds after balloon inflation versus a mean of 31 seconds in the absence of beta blockade (p less than 0.05). Thus the use of ultrashort-acting beta blockade appears to diminish the extent and delay the onset of myocardial ischemia during acute coronary occlusion.     

经皮冠状动脉腔内成形术缺血预适应对QT离散度的影响

记录７０例冠心病人经皮冠状动脉腔内成形术时体表和冠脉内心电图发现，随球囊充盈次数增加，ＳＴ段抬高幅度减低，心绞痛出现时间延长，最大ＱＴ间期缩短及ＱＴ离散度和ＪＴ离散度减低，提示ＰＴＣＡ时多次短暂心肌缺血可能由于缺血预适应而诱发心肌内在抗心律失常保护作用。     

Intracoronary electrocardiogram for early detection of myocardial viability during coronary angioplasty in acute myocardial infarction.

PURPOSE: The clinical value of the intracoronary electrocardiogram (ECG) for detecting myocardial viability in acute myocardial infarction was evaluated by thallium-201 scintigraphy and left ventriculogram at the chronic stage. METHODS: Intracoronary ECGs, recorded from the tip of a guidewire during emergency coronary angioplasty, were obtained in 65 patients with reperfused anterior myocardial infarction. Further ST segment elevation of greater than 0.2 mV detected during the balloon inflation was taken as significant. The left ventricular segmental shortening was measured from left ventriculograms recorded at acute and chronic stages. The infarct area was defined as viable when a thallium uptake of more than 50% was detected on thallium-201 myocardial scintigraphy at the chronic stage. RESULTS: During emergency coronary angioplasty, significant ST segment elevation was noted in 45 patients (Group A); however, the ST segment was not significantly elevated in the other 20 patients (Group B). The infarct area of 42 patients in Group A and three patients in Group B was viable on scintigraphy. Improvement left ventricular wall motion of the infarct area was observed in 39 of the 42 patients in Group A and the three patients in Group B. Therefore, intracoronary ECG can predict reversible dysfunction with excellent sensitivity (92.9%) and specificity (73.9%). CONCLUSIONS: The myocardium within an infarct area can be regarded as viable when a further ST segment elevation occurs on intracoronary ECG during emergency coronary angioplasty. It is useful, therefore, to monitor the intracoronary ECG during coronary angioplasty balloon inflation to assess the myocardial viability of the infarct area.     

Limitation of myocardial ischemia by collateral circulation during sudden controlled coronary artery occlusion in human subjects: a prospective study

We have shown improvement in collateral filling immediately after sudden controlled coronary occlusion in human subjects undergoing elective coronary angioplasty. It has been suggested but not proved that collateral circulation can limit myocardial ischemia. We prospectively studied 23 patients with isolated left anterior descending (n = 14) or right coronary (n = 9) disease and normal left ventriculograms during elective coronary angioplasty. A second arterial catheter was used for injection of the contralateral artery to assess collateral filling before balloon placement and during coronary occlusion by balloon inflation. Left ventriculography was performed during another inflation. Grading of collateral filling was as follows: 0 = none, 1 = filling of side branches only, 2 = partial filling of the epicardial segment, 3 = complete filling of the epicardial segment. Indexes of myocardial ischemia included percent of the left ventricular perimeter showing new hypocontractility and the sum of ST segment elevation measured on a simultaneous 12-lead electrocardiogram recorded during each inflation. Collateral filling during balloon occlusion and indexes of ischemia were assessed at 30 to 40 sec into inflation. Aortic pressure and heart rate did not correlate with the percent hypocontractile perimeter nor the sum of ST segment elevation. There was a significant correlation between the grade of collateral filling during inflation and both percent hypocontractile perimeter (r = -.85) and the sum of ST segment elevation (r = -.87). Anginal pain occurred in all patients with grade 0 or 1 collateral filling but in only 36% of patients with grade 2 or 3 collaterals. In conclusion, collateral circulation limits myocardial ischemia as assessed by the extent of new ventricular asynergy and electrocardiographic changes during coronary occlusion in patients.     

The Initial Electrocardiographic Pattern in Acute Myocardial Infarction

Background: The ECG is the most widely used accessory for early diagnosis and risk stratification of patients with acute myocardial infarction (AMI). Previous studies have concentrated on the association between either the number of leads with ST segment deviation (elevation and depression) or the total amount of ST segment elevation and/or depression and prognosis. However, the results are conflicting. Methods: A different method is to use the grades of ischemia as an estimate of infarct or size and prognosis. Grade I ischemia is defined as tall peak T waves with < 0.1 mV ST segment elevation; grade II as ST segment elevation with positive T waves, without distortion of the terminal portion of the QRS; and grade III as ST segment elevation, positive T waves, and distortion of the terminal portion of the QRS. Grade III ischemia on the admission ECG is associated with larger final infarct size and increased mortality. Results: In patients with inferior wall AMI, especially those with prior infarction, the pattern of precordial ST segment depression is even more important and maximal ST depression in V4-V6 is associated with high mortality. Moreover, meticulous interpretation of the initial ECG pattern provides information about the probable site of the culprit obstructive coronary lesion. Conclusion: Thus, the admission ECG of AMI can assist not only in diagnosis, but also in estimation of infarct size, correlation with the underlying coronary anatomy and risk stratification.