提高开胸结扎法建立猪心肌梗死模型成功率探讨

目的:探讨提高开胸结扎法建立猪急性心肌梗死模型成功率的方法.方法:幼猪16只,结扎组(10只)复合麻醉,机械通气,正中切口开胸结扎前降支中下1/3,术前、术中、术后静滴、术中浸润利多卡因;假结扎组(6只)穿线不结扎;心电图、饲养3周后冠状动脉造影、心肌核素显像检查、心脏标本HE及切片2,3,5-氯化三苯基四氮唑(TTC)染色.结果:结扎组手术成功率90%.心电图ST段明显抬高;3周后冠状动脉造影提示前降支中远端完全闭塞;核素心肌显像提示前壁、心尖部放射性稀疏或缺如;HE染色见均匀一致的纤维结缔组织增生;切片TTC染色不着色.结论:手术前后静滴及表面浸润利多卡因,正中切口开胸结扎冠状动脉前降支是建立猪心肌梗死模型有效的方法,可明显提高成功率.     

急性前壁心肌梗死心电图对左冠状动脉前降支病变的诊断价值

目的探讨心电图在ST段抬高型急性前壁心肌梗死时左冠状动脉前降支(LAD)病变部位的诊断价值。方法对89例经冠状动脉造影证实前降支为梗死相关动脉患者的18导联心电图进行回顾性分析。结果心电图STV2抬高≥3mm、STV3抬高≥2mm、STⅡ,Ⅲ,avF压低≥1mm对前降支近段闭塞的判断有较大的价值,其阳性率与前降支远段闭塞组差异有显著性意义,其诊断的特异性和敏感性均较高。结论ST段抬高型急性前壁心肌梗死时体表心电图与左冠状动脉前降支闭塞部位有明显相关性。     

不同部位冠状动脉阻塞的心电图特征

目的 通过冠状动脉（冠脉）造影和标准心电图的对比，找出不同部位冠脉阻塞的心电图特征。方法 对84例急性心肌梗死的患者作了冠脉造影及12导联心电图检查，将不同部位冠脉阻塞的造影结果与心电图作了对比。结果 左前降支阻塞时V2－4ST段抬高的发生率最高，其敏感性、特异性、阳性预测值和阴性预测值分别为81．4％、85．7％、80．3％及86．6％。右冠脉阻塞时aVF的SF段抬高的发生率最高，其敏感性、特异性、阳性预测值和阴性预测值分别为86．7％、96．3％、92．9％。右旋支阻塞时任何导联ST段抬高发生率的敏感性和阳性预测值都＜25．0％，特异性和阴性预测值也＜79．0％。结论 心电图指标对右冠脉及左前降支阻塞的诊断优于左旋支。     

实验用猪急性心肌梗死模型的制备

目的：探讨经皮冠状动脉内球囊封堵法建立实验用猪急性心肌梗死模型的可行性及有效性。方法：健康家猪14只，3～5月龄，体重25～40kg（35．5±6．6）。麻醉后穿刺股动脉，行冠脉造影后沿血管送冠脉球囊至冠状动脉左前降支（LAD）近中段，即第二间隔支动脉分出处。动物随机分为2组，A组动物（n=7）行缺血预适应处理，依次扩张球囊阻断前向血流1、2、5min，每次间隔60s，然后扩张60min，扩张压力为2atm。B组动物（n=7）不行缺血预适应处理，直接扩张球囊阻断前向血流扩张60min，扩张压力为2atm。建立模型前、建立模型后1h行心脏MRI及心电图检查，术中行心电监护。结果：成功建立猪心肌梗死模型12例，B组动物死亡2例。术中共有12例动物发生室颤，其中10例经过电复律等抢救成功转复。12例建模成功动物术中心电图出现急性心肌梗死典型图形变化，术后心脏MRI检查出现间隔及前壁首过灌注缺损，延迟强化。结论：经皮腔内冠脉球囊封堵冠状动脉可以建立实验用猪急性心肌梗死模型，缺血预处理可提高建模成功率。     

脂联素后处理对大鼠心肌缺血-再灌注损伤的保护作用

目的：探讨脂联素（ADP）后处理对大鼠心肌缺血‐再灌注损伤（MIRI）是否有保护作用。方法 SD大鼠随机分为：（1）假手术组（Sham组）,冠状动脉左前降支（LAD）仅穿线不断流;（2）心肌缺血‐再灌注损伤组（MIRI组）,LAD结扎30 min后再灌注120 min;（3）脂联素后处理组（ADP组）,LAD再灌注前20 min注射 ADP ,其余同 MIRI组。检测各组血浆乳酸脱氢酶（LDH）、心肌肌钙蛋白I（cTnI）和丙二醛（MDA）的水平,检测心肌超氧化物歧化酶（SOD）和MDA的水平,各组心肌 HE染色并描记心电图。结果 MIRI组血浆 LDH（735．21±110．92）U／L、cTnI（37．96±5．97）μg／mL 和 MDA（4．55±0．18）nmol／L较Sham组升高（P＜0．05）,ADP组血浆LDH（579．25±69．01）U／L、cTnI（21．07±5．77）μg／mL和MDA（2．99±0．22）U／L水平较MIRI组降低（P＜0．05）;与Sham组相比,MIRI组心肌SOD水平（11．47±1．67）U／mg降低而MDA水平（7．99±0．59）nmol／mg升高（P＜0．05）;与 MIRI组相比,ADP组心肌SOD水平（13．93±0．97）U／mg升高而MDA 水平（5．74±0．64）nmol／mg降低（P＜0．05）。结论 ADP后处理可以减轻大鼠MIRI ,可能与减少脂质过氧化和增强自由基清除有关。     

Double coronary artery thrombosis presenting as acute extensive anterior ST-segment elevation myocardial infarction

Simultaneous thrombosis of more than one coronary artery is an uncommon angiographic finding in acute ST-segment elevation myocardial infarction (STEMI), and usually leads to cardiogenic shock or even sudden cardiac death. We reported a 56-year-old man presenting with persistent chest tightness and ST-segment elevation over precordial leads in electrocardiography (ECG). Emergent coronary angiogram showed total occlusion of both the proximal right coronary artery (RCA) and the proximal left anterior descending artery (LAD). We performed thrombus aspiration and stenting over the LAD with thrombolysis in myocardial infarction (TIMI) III flow to the distal LAD. However, diminishing collateral flow to the distal RCA complicated with complete atrioventricular block (CAVB) and cardiogenic shock developed thereafter. Because distal embolization of the collateral circulation from the LAD to the distal RCA was suspected, thrombus aspiration and stenting over the proximal RCA were performed. After reperfusion of the RCA, the patient's hemodynamic status stabilized and he recovered uneventfully.     

大鼠左冠状动脉不同结扎时间对心肌梗死面积及心功能的影响

目的:探索大鼠左冠状动脉前降支不同结扎处理后,对心肌形态学及心功能的影响,以建立适合移植干细胞再生修复心肌梗死研究的稳定、可靠和更合乎发病机理的动物模型。方法:雄性W istar大鼠70只,随机分为六组即:假手术组、结扎(15 m in、30 m in、45 m in、60 m in)再灌、结扎非再灌。于处理后1 d、1周、2周或4周动态观察心肌梗死变化,并于处理一月后测量动脉收缩压(ASP)、动脉舒张压(ADP)、左室收缩压(LVSP)、左室舒张末压(LV-EDP)及左室压力上升及下降最大速度(±dp/dtm ax)。结果:引起明显的心肌梗死至少需要结扎30 m in。结扎(45m in、60 m in)再灌、结扎非再灌的心肌梗死明显,并观察到梗死区域心肌已绝大部分纤维化,且梗死面积变化较恒定。同时测定不同结扎时间心功能的变化发现,结扎(45 m in、60 m in)再灌或结扎非再灌各组ASP、ADP、LVSP、±dp/dtm ax显著下降,LVEDP明显升高。并且不同结扎时间处理后,大鼠心功能的变化与心肌梗死后的梗死面积变化密切相关。结论:建立了在实验大鼠左冠状动脉前降支中上1/3处结扎45 m in以上的大鼠心肌梗死模型,不仅合乎临床心肌梗死的发病机理,而且梗死部位、梗死区域面积稳定,适合于移植细胞再生修复心肌梗死的研究。     

急性前壁心肌梗死时体表心电图初步预测前降支闭塞部位

目的：探讨前壁、广泛前壁急性心肌梗死（AMI）患者体表心电图（ECG）改变与梗死相关动脉（IRA）定位的关系。方法选择该院2008年1月1日至2013年3月31日期间入院的AMI患者171例,将患者分为近段组和中远段组,对患者的ECG与冠状动脉照影（CAG）的资料进行回顾性对比分析。结果STI、aVL抬高、STⅡ、Ⅲ、aVF压低、STaVR导联抬高时提示前壁、广泛前壁AMI的IRA为左前降支（LAD）近端闭塞而不是中远端闭塞的可能性较大（P＜0．05）。结论解读有价值的ECG指标,能初步推测前壁AMI的IRA及其闭塞部位。     

Establishment and evaluation of a swine model of acute myocardial infarction and reperfusion–ventricular fibrillation–cardiac arrest using the interventional technique

BackgroundVentricular fibrillation is the main cause of sudden cardiac death among patients with acute myocardial infarction (AMI). Substantial benefits could be obtained by both researchers and practitioners if an AMI reperfusion-ventricular fibrillation-cardiac arrest model were established.MethodsTwenty swine were anesthetized and underwent occlusion of the left anterior descending branch for 90 minutes prior to blood reperfusion. Throughout this process, continuous 12-lead electrocardiography (ECG) was used to monitor heart rate, rhythm, and electrocardiogram alteration. Thereafter, AMI was confirmed by ECG and left ventricular angiography. Heart tissue was collected for pathological analysis, and for evaluation of the establishment of a model of AMI reperfusion.ResultsSeven swine died during the model establishment, and the 13 surviving swine were proven to have myocardial infarction; nine of those survivors had ventricular fibrillation–cardiac arrest after reperfusion based on the electrocardiograph and pathological examination.ConclusionBlocking the left anterior descending branch by inflation of an over-the-wire coronary balloon catheter in swine can result in successful establishment of a swine model of AMI and reperfusion–ventricular fibrillation–cardiac arrest, with good reproducibility and a high survival rate.     

前降支单支病变急性心肌梗死患者的心电图ST段分析

目的 探讨冠状动脉前降支(LAD)单支病变致ST段抬高心肌梗死(STEMI)患者心电图ST段变化对于冠脉闭塞部位的判断.方法 1996年1月至2009年3月我院急性心肌梗死患者,均行冠状动脉造影术,单支病变468例,其中LAD单支病变也是犯罪血管的STEMI共170例.依据LAD闭塞部位分两组,近段组77例,中远段组93例.定量记录心电图各导联ST段的偏移幅度.结果 以冠脉造影为金标准,心电图ST段表现:aVL抬高≥0.1 mV,aVL抬高＞aVR和下壁导联ST段压低之和≥0.1 mV,预测LAD近段病变的敏感度39.2%～50.6%,特异度77.4%～7 8.5%,差异有统计学意义(P＜0.05).心电图ST段表现:无Ⅱ导联ST段压低≥0.1 mV、无aVF导联ST段压低≥0.1 mV,或无下壁ST段压低之和≥0.1 mV,预测LAD中远段病变的敏感度74%～86%,特异度31%～50%,差异均有统计学意义(均P＜0.05).结论 LAD单支病变所致STEMI患者的心电图ST段变化,对判断LAD不同部位闭塞有提示意义.

Abstract：

Objective To analyze the characteristics of the electrocardiogram(ECG)of left anterior descending coronary artery(LAD)occlusion in patients with acute STelevation myocardial infarction (STEMI).Methods Patients included were those diagnosed with STEMI in Peking Union Medical College Hospital from January 1996 to March 2009,and underwent coronary angiography(CAG).The infarction related artery(IRA)was LAD,and there were no significant stenosis in left circumflex artery and right coronary artery.A total of 170 cases were consecutively enrolled.They were divided into 2 groups according to occlusive sites of the LAD:LAD proximal(n =77),LAD medius distal group(n =93).Standard 18leads ECG within 12 hours from the onset of STEMI were recorded and ST segment deviation was analyzed quantitatively.Results Proximal LAD occlusion as IRA was diagnosed with aVL ≥ 0.1 mV,ST aVL ＞aVR,sum of Ⅱ,Ⅲ and aVF STsegment depression ≥ 0.1 mV,in which sensitivity was 39.0%,37.7% and 50.6%,specificity was 78.5%,77.4% and 74.2% respectively.Statisticully significarct(P＜0.05).Medius-distal LAD occlusion as IRA was diagnosed with no Ⅱ ST depression,aVF ST depression and sum of Ⅱ,Ⅲ and aVF ST segment depression ＞0.1 mV,In which sensitivity were 86.0%,81.7% and 74.2% and the were 31.2%,48.1% and 50.6% respectively.Statisticully significarct(P ＜0.05).Conclusion In STEMI patients with isolated LAD occlusion,ECG can be useful to predict the occlusion site.     

结扎不同冠脉建立兔急性心肌梗死模型的特点比较

目的对结扎不同冠脉分支制备兔急性心肌梗死模型的方法进行对比研究,并探讨其在科研应用中的意义。方法选择30只新西兰大白兔,随机分为2组,非人工通气状态下,分别结扎左前降支(left anterior descending,LAD)及左旋支的粗大恒定分支左室支(left ventricular branch,LVB),并于结扎前及结扎后30 min、24 h、1周行心电图及心肌酶检测,结扎前及结扎后24 h、1周经静脉行心肌超声造影(myocardial contrast echocardiography,MCE)检查,结扎后1周行冠脉造影及血液动力学指标检测,随即处死动物留取左室标本称重并进行氯化三苯四氮唑(TTC)染色测定梗死面积。结果①冠脉结扎术后30 min两组心电图ST均明显抬高,24 h后LAD组即明显回落(P<0.05),1周后差异更为明显(P<0.01)。②术后1周冠脉造影证实LAD组81.8%近中段闭塞,LVB组100%近中段闭塞,差异无统计学意义(P>0.05)。③造模1周后两组收缩压(systolic blood pressure,SBP)、舒张压(diastolic blood pressure,DBP)、左心室压力最大上升和下降速率(maximumrate of rise and descend of left ventricular pressure,±dp/dt max)、左室舒张末压(left ventricular end-diastolic pressure,LVEDP)、射血分数(ejection factor,EF)均较术前明显减低(P<0.05),左心室舒张末期内径(left ventricular end-diastolic dimension,LVEDD)较术前增大,LVB组较LAD组变化更为明显(P<0.05),尤以A×β最为显著(P<0.01)。④TTC染色后计算LAD组心梗面积小于LVB组(P<0.05),且心梗前后心肌灌注指标A×β变化值与±dp/dt max、心梗面积呈显著正相关(r=0.62、0.55、0.80,P<0.05)。结论结扎LVB建立的兔急性心肌梗死模型梗死面积理想,范围稳定可靠,可用于长期随访观察的急性心肌梗死相关研究,而结扎LAD则更适用于急性再灌注或侧支循环实验观察。     

大蒜素可预防心肌梗死猪模型再灌注无复流现象

Objective： To evaluate whether garlicin can prevent reperfusion no-reflow in a catheter-based porcine model of acute myocardial infarction （AMI）. Methods： Twenty-two male Chinese mini swines were randomized into 3 groups： sham-operation group （n=6）, control group （n=8）, and garlicin group （n=8）. The distal part of left anterior descending coronary artery （LAD） in swines of the latter two groups was completely occluded by dilated balloon for 2 h and a successful AMI model was confirmed by coronary angiography （CAG） and electrocardiograph （ECG）, which was then reperfused for 3 h. In the sham-operation group, balloon was placed in LAD without dilatation. Garlicin at a dosage of 1.88 mg/kg was injected 10 min before LAD occlusion until reperfusion for 1 h in the garlicin group. To assess serial cardiac function, hemodynamic data were examined by catheter method before AMI, 2 h after occlusion and 1, 2, and 3 h after reperfusion. Myocardial contrast echocardiography （MCE） and double staining with Evans blue and thioflavin-S were performed to evaluate myocardial no-reflow area （NRA） and risk area （RA）. Results： Left ventricular systolic pressure and left ventricular end-diastolic pressure significantly improved in the garlicin group after reperfusion compared with the control group （P〈0.05） and 2 h after AMI （P〈0.05）. MCE showed garlicin decreased reperfusion NRA after AMI compared with the control group （P〈0.05）. In double staining, NRNRA in the garlicin group was 18.78%, significantly lower than that of the control group （49.84%, P〈0.01）. Conclustions： Garlicin has a preventive effect on the porcine model of myocardial infarction reperfusion no-reflow by improving hemodynamics and decreasing NRA.     

墓碑形改变的急性心肌梗死血管梗塞部位的相关性

目的　探讨急性心肌梗死(AMI)ST段呈墓碑形改变的血管梗塞部位的相关性。方法　收集10 4例进行了冠状动脉造影(CAG)AMI的患者,其中19例心电图(ECG)有墓碑形改变。结果　对比墓碑形(A组)与非墓碑形(B组)的CAG ,显示:墓碑形改变多见于前壁心梗(P <0 .0 0 1) ;墓碑形更多见于左前降支(LAD)近段及严重病变(P <0 .0 5及P <0 .0 1) ;墓碑形多见于多支病变(P <0 .0 5 )。结论　AMI时ST段呈墓碑形改变多与LAD近段严重及多支病变相关,预后较差。     

CORONARY ANGIOGRAPHY INFARCTION IN DOGS DURING ACUTE MYOCARDIAL A COMPARISON OF THE HEMODYNAMIC EFFECTS OF IONIC AND NONIONIC CONTRAST MEDIA

We compared the hemodynamic effects of three nonionic contrast media/lnopamidol (IOP), iohexol (IOH), and ioversol (IOV)-with each other and the standard ionie contrast media/hypaque76 (H76) in left anterior descending coronary artery (LAD) occlusion in dogs during coronary angiography. In 13 0pened chest anesthetized dogs, the maximal change in left ventricular (LV) systolic pressure, mean aortic pressure, LV diastolic pressure and LV dp/dt during 10 ml left main coronary artery injec tions of H76, IOP, IOH, and IOV one hour after LAD occlusion were recorded. Each nonionic agent produced significantly less hemodynamic abnormali ties than H76. There were no significant differences between any of the nonionic agents on any hemo dynamic parameters. Therefore these agents may be preferable in patients with acute myocardial infarc tion or significantly impaired myocardial function.     

经皮球囊扩张封堵冠状动脉前降支制备巴马香猪急性心肌梗死模型

目的探讨经皮球囊扩张封堵冠状动脉前降支（LAD）制备巴马香猪急性心肌梗死（AMI）模型的方法及可行性。方法经右股动脉置人冠状动脉球囊导管至左前降支;预适应3～4次,每次球囊充盈30s,间隔5～10min;以3～5atm扩张球囊封闭LAD远端血流,40min后撤除球囊。结果8头巴马香猪中有6头存活,造模成功率为75％。模型梗死面积变异系数为11．7％（33．2±3．9）。封堵后心电图呈动态变化,心肌酶学指标（CK、CK—MB、cTnI、Myo、LDH）较术前明显升高,心脏彩超左心室舒张末内径、左心室舒张末容积及左心室收缩末容积均增大,LVEF均下降,部分实验猪出现心室壁瘤,TIC染色、HE染色证实心肌梗死模型建立成功。结论经皮球囊扩张封堵法制备巴马香猪急性心肌梗死模型成功率高,保持了梗死区冠脉可重复进行造影,为干细胞植入梗死区心肌治疗AMI提供了较好的动物模型。     

Estimation of microinhomogeneity of conduction impairment by wavelet analysis during early phase of myocardial ischemia in pigs

Ventricular fibrillation (VF) is most frequent in the very early phase in acute coronary occlusion, and is triggered by the re-entrant mechanism in this phase. An inhomogeneous conduction in the ischemic myocardium would be substrates for re-entry. The aim of this study was to examine the relationship between the severity of irregularities of the QRS complex and VF. Eleven pigs were analyzed, and the heart was fixed in the pericardial cradle. Ag-AgCl bipolar electrodes were fixed on the epicardium in ischemic and non-ischemic regions. The proximal portion of the left anterior descending coronary artery was occluded for one hour. Electrocardiograms (ECGs) were continuously recorded on a magnetic tape, and wavelet analysis was performed on signal-averaged ECG (25 beats) every 60 sec after the experiment. The number of local maxima (N) and the duration between the first and the last local maximum (D) were automatically measured. N and D significantly increased in the ischemic area, but not in the non-ischemic area. N and D increased approximately twofold just before the occurrence of VF in 8 fibrillated pigs (p<0.01, each). There were significant positive linear relationships between the rate of increase in N and D to VF and basal heart rate before coronary occlusion (r=0.90, p <0.01 in N, r=0.84, p <0.01 in D at 160 Hz). These results suggest that there would be a threshold inhomogeneous conduction for the occurrence of VF and an increase in heart rate would accelerate the inhomogeneous conduction in acute myocardial ischemia.     

de Winter综合征， 一种易被忽视却致命的疾病： 1例报告

de Winter综合征是与ST段抬高型心肌梗死等同的一种特殊疾病,其特征是没有明显的ST段抬高,表现为上斜型ST段压低,心前导联出现高而对称的T波,并通常与冠状动脉左前降支完全阻塞有关。本文中我们报告1例de Winter综合征病例,该63岁男性患者初始心电图未显示ST段抬高,但随后在冠状动脉造影中证实近端冠状动脉左前降支完全闭塞。该患者通过机械再灌注治疗和支架置入术后得到成功治疗。临床医生通常对此病认识不足,因此常导致较高的死亡率。迅速识别该综合征的这种ECG模式以确保及时通过经皮冠状动脉介入术进行有效的再灌注治疗对于挽救患者的生命至关重要。     

非体外循环心脏不停跳下冠状动脉旁路移植术

目的:探讨非体外循环心脏不停跳下冠状动脉旁路移植术（off-fiump coronary　artery　bypass　grafting,OPCAB）治疗缺血性心脏病的临床经验和手术结果。方法:2001年～2002年完成冠状动脉旁路移植术共23例,手术均采用胸骨正中切口,在非体外循环心脏不停跳下完成,游离左侧乳内动脉均与前降支吻合,取大隐静脉及烧动脉与回旋支、后降支等其他部位血管吻合。冠状动脉吻合口和近端吻合口分别用7.0Prolene及6-0Prolene缝线连续法缝合。结果:全组手术无死亡,术后随访2个月～14个月,心绞痛症状均明显缓解,心功能Ⅰ级～Ⅱ级,术后心绞痛复发2例,给子扩冠、抗凝治疗后好转。术后并发右侧脑梗死1例,融栓、抗凝等治疗后病情好转。结论:非体外循环心脏不停跳下冠状动脉旁路移植术在缺血性心脏病的外科治疗中是一种理想、安全、有效的手术方法。     

门控心肌灌注和心肌代谢显像评价新方法制作小型猪室壁瘤模型的可行性

目的 应用门控心肌灌注和心肌代谢显像评价新方法建立小型猪室壁瘤模型的可行性。方法 中华小型猪16只,采用结扎冠状动脉钝缘支远端,并在左前降支(LAD)第1对角支分叉处以下1cm处放置Ameroid 环的方法建立模型。在建模后第4周采用门控心肌灌注/代谢显像观测左心室灌注受损情况(TPD)、存活心肌占左心室百分比(Mismatch)、室壁瘤形成情况以及左心室射血分数(LVEF)、左心室舒张末期容积(EDV)、左心室收缩末期容积(ESV)等指标。建模后第8周处死动物,取病理结果进行分析。结果 建模总体病死率为31.2% (11/16),病理结果证实,8头小猪心尖部有室壁瘤形成。8头小猪完成术后第4周显像,显像结果提示,6头小猪心尖部有室壁瘤形成,2头小猪仅呈现非透壁性心肌梗死表现。与心肌梗死组获得的参数相比较,室壁瘤组的左心室灌注总受损范围(TPD)、舒张末期容积(EDV)、收缩末期容积(ESV)明显增高,左心室射血分数(LVEF)及存活心肌百分比(Mismatch)明显下将,差异有统计学意义(P<0.05)。结论 通过门控心肌灌注和心肌代谢显像评价结扎冠状动脉钝缘支远端并在左前降支第1对角支下1cm处放置Ameroid 环的方法,是比较理想的建立室壁瘤模型的方法,该方法操作简单、可行,建模成功率高,动物存活率满意,建模后第4周左心室重构明显。     

急性前壁心肌梗死时心电图对预测前降支闭塞部位的作用

目的:探讨心电图对预测急性前壁心肌梗死时前降支闭塞部位的作用。方法:对74例患者的心电图和冠状动脉造影资料进行对比分析。结果:①前间壁AMI患者,血管闭塞部位均发生于大对角支开口远端。②前壁伴高侧壁AMI患者,血管闭塞部位在大对角支开口近端者占74.1%。③前壁AMI患者合并下壁导联ST段抬高时,73.3%为前降支优势动脉远端病变,合并下壁导联ST段压低者,前降支非优势动脉近端病变占60%,下壁导联ST段无改变组中,前降支优势动脉近端和非优势动脉远端病变所占比例近似。结论:前壁AMI时,心电图对前降支长度及闭塞部位有重要预测价值。