左回旋支动脉阻塞相关的心肌梗死的临床特征

目的：探讨左回旋支动脉阻塞相关的ST段抬高型与非ST段抬高型急性心肌梗死患者的临床特征。方法：对连续收治的86例冠状动脉左回旋支相关的急性心肌梗死行冠状动脉介入治疗患者的临床资料进行回顾性分析,根据心电图的表现分为两组,ST段抬高型心肌梗死（STEMI）组（32例）,非sT段抬高型心肌梗死（NSTEMI）组（54例）,比较两组临床特征及预后。结果：与NSTEMI组比较,STEMI组血清肌酐水平[（80±23）／μmmol／L比（100±30）μmmol／L],主动脉内球囊反搏（3．7％比18．8％,P〈0．05）、有创呼吸机使用（1．9％比15．6％）、缺血性二尖瓣返流（13．0％比40．6％）、完全性房室传导阻滞（0比9．4％）,左冠状动脉优势型比例（7．4％比28．1％,P〈0．05）显著升高,左室舒张末期直径（LVEDd）[（46±4）mm比（48±5）mm]显著扩大（P〈0．05或〈0．01）。STEMI组三支血管病变显著低于NSTEMI组（46．9％比72．2％,P〈0．05）,两组住院死亡率无显著差异（3．1％比0％,P〉0．05）。结论：左回旋支动脉阻塞相关的ST段抬高型心肌梗死比非ST段抬高型心肌梗死的心功能差,这可能与左冠状动脉优势型较多有关。     

Myocardial bridging of left circumflex coronary artery associated with acute myocardial infarction

Myocardial bridging of coronary arteries has been associated with myocardial infarction (MI), conduction disturbances, and sudden cardiac death. There are several reports on MI in association with myocardial bridging of the left anterior descending coronary artery. Here we present a case report of acute MI associated with myocardial bridging of the left circumflex coronary artery.     

Clinical outcomes in patients with acute left circumflex/obtuse marginal occlusion presenting with myocardial infarction

Background: Acute occlusion of left circumflex (LCx) or obtuse marginal (OM) arteries can present as ST elevation myocardial infarction (STEMI) or non‐ST elevation myocardial infarction (NSTEMI). NSTEMI patients (pts) with occlusions have worse outcomes than those without occlusions, but no studies specifically examine outcomes in acute myocardial infarction (AMI) pts with LCx/OM occlusion. This study aims to define the incidence of NSTEMI in pts presenting with LCx/OM occlusion and analyzes clinical characteristics and outcomes in those presenting with NSTEMI compared to STEMI. Methods and Materials: A review of our catheterization and STEMI database was performed to identify AMI pts presenting with LCx or OM occlusion from 1/1/2007 to 7/31/2009 at the Medical College of Virginia. Patients were divided into STEMI and NSTEMI groups, and a chart review was performed. Primary end‐points were in‐hospital mortality (HM), cardiogenic shock (CS), and in‐hospital CHF. Secondary end‐points included peak CK‐MB and time to catheterization, as well as combined end‐points of 1‐month mortality, and recurrent AMI and CHF. Results: Fifty‐six pts met inclusion criteria, 54% of whom presented with NSTEMI. STEMI pts were significantly more likely to meet the primary end‐points, as well as the combined secondary end‐points. They had shorter times to catheterization but larger infarct sizes. Patients with left or mixed coronary dominance were more likely to have STEMI. Conclusions: AMI pts with LCx/OM occlusion present with NSTEMI as often as STEMI. Those with NSTEMI have better outcomes, which may be related to right coronary dominance. Summary: Patients with acute LCx or OM occlusion present with NSTEMI as often as STEMI, but those with STEMI have worse outcomes. The difference in presentation may be related to coronary dominance. (J Interven Cardiol 2011;24:27–33)     

Emergency stenting of totally occluded left main coronary artery in acute myocardial infarction

We report a case of emergency stenting for acute occlusion of the left main coronary artery in the setting of acute myocardial infarction. Although stent implantation allowed prompt revascularization and successful immediate management of this life-threatening condition, subacute stent thrombosis occurred, requiring re-PTCA followed by surgical revascularization. This case suggests that stenting of an acutely occluded left main coronary artery may be a life-saving procedure but should only be used as a bridge to surgery rather than a definitive treatment modality.     

Congenital absence of the left circumflex artery associated with inferior myocardial infarction

Congenital absence of the left circumflex artery is a rare anomaly of the coronary arteries. A 52-year-old man who developed acute inferior myocardial infarction underwent coronary angiography which revealed the absence of the left circumflex artery and that the surrounding structures were supplied by the infarct-related super-dominant right coronary artery. Two stents were implanted into the right coronary artery and one stent into the mid portion of the left anterior descending artery. Follow-up coronary angiography at 67 months showed no detectable restenosis, and 64-slice multidetector computed tomography confirmed the absence of the left circumflex artery. The circumflex artery as a terminal extension of a culprit right coronary artery has not been previously reported.     

Left internal mammary-to-left circumflex coronary artery collateral pathway in a patient with occluded left circumflex artery

A unique case of left internal mammary artery-to-circumflex coronary artery collateral pathway, which was conceivably encouraged to develop by coronary occlusion. The pathway provided sufficient collateral perfusion to preserve the local myocardial performance.     

19例梗死相关动脉为优势左回旋支的急性心肌梗死心电图表现

目的分析19例梗死相关动脉为优势左回旋支的急性心肌梗死患者的心电图表现,总结其特点。方法回顾性分析2000年9月至2005年12月急性心肌梗死患者的心电图资料,25例急性心肌梗死经冠状动脉造影证实梗死相关动脉为优势左回旋支,选取其中发病12h内有12或18导联心电图记录的19例,分析其发病时心电图表现及特征。结果19例患者中2例表现为非ST段抬高性心肌梗死,冠脉造影证实血管已再通,血流正常。17例表现为下壁ST段抬高性心肌梗死,15例合并后壁ST段抬高,2例V4RST段抬高,14例V4RST段压低。12例ST段抬高(STIII↑>STII↑)和ST段压低(STaVL↓>STI↓)同时出现。12例aVR导联ST段压低。19例中3例合并有完全性房室阻滞,1例合并高度房室阻滞。结论梗死相关动脉为优势左回旋支的急性心肌梗死患者心电图图形特点类似右冠脉闭塞的ST段抬高心肌梗死,STIII↑>STII↑,STaVL↓>STI↓,两者很难鉴别,下壁、后壁ST段抬高而RV4和STaVR压低可能是重要特点。     

Left ventricular dysfunction in acute myocardial infarction due to isolated left circumflex coronary artery stenosis

The characteristics of regional and global left ventricular dysfunction due to isolated left circumflex (LC) artery stenosis were determined from the contrast ventriculograms of 52 patients studied during acute myocardial infarction. In patients with a left dominant coronary circulation (35%), the severity, circumferential extent and location of hypokinesia resembled those of right coronary artery stenosis. However, in patients with a right dominant or balanced circulation (65%), the location of LC artery-related hypokinesia varied over the entire left ventricular contour, overlapping with the territories of the left anterior descending and right coronary arteries. The method for measuring the severity of hypokinesia was adjusted to take into account the wide territory of the LC artery. This enhanced the sensitivity of the method, particularly in the right anterior oblique view, as indicated by the greater severity of hypokinesia measured (-2.5 +/- 0.9 vs -1.8 +/- 1.1 standard deviations by our previously published method, p less than 0.001). However, the overlap of the artery territories may make it difficult to selectively measure the dysfunction due to stenosis of an artery of interest in patients with multiple infarctions. The circumferential extent of hypokinesia due to LC artery thrombosis was greater in the left than the right anterior oblique view. When averaged over both views, the size of the dysfunctional segment approached that due to left anterior descending coronary artery thrombosis, exceeding the size previously reported. These results suggest that current eligibility criteria for thrombolytic therapy select patients with extensive LC artery beds.     

Clinical features and outcome of patients with direct percutaneous coronary intervention for acute myocardial infarction resulting from left circumflex artery occlusion

BACKGROUND: Little is known about the clinical features and outcome of patients with left circumflex artery (LCX) infarct-related acute myocardial infarction (AMI). This study was conducted to investigate the clinical features and outcome of patients who underwent direct percutaneous coronary intervention (d-PCI) for AMI caused by LCX occlusion, and to discover prognostic determinants in this clinical setting. METHODS AND RESULTS: Between May 1993 and October 2000, a total of 819 patients with AMI underwent d-PCI in our hospital. Sixty-seven patients (8.2%) who had LCX infarct-related AMI constituted the population of this study. Ten of 67 patients (14.9%) were in cardiogenic shock. Angiographic findings demonstrated that the incidences of triple-vessel disease, reference lumen diameter (RLD) of the LCX > or = 4.0 mm, and LCX as the dominant artery in these patients were 26.9%, 22.4%, and 34.3%, respectively. Sixteen patients (23.9%) had unsuccessful reperfusion (defined as Thrombolysis in Myocardial Infarction flow < or = 2). Univariate analysis showed that dominant LCX, RLD of the LCX > or = 4.0 mm, cardiogenic shock, precordial ST-segment depression, and complete atrioventricular block were significantly related to unsuccessful reperfusion. Multiple stepwise logistic regression analysis demonstrated that dominant LCX and cardiogenic shock were significant independent predictors of unsuccessful reperfusion. The 30-day mortality rate in the 67 patients was 14.9%. Univariate analysis demonstrated that triple-vessel disease, dominant LCX, cardiogenic shock, poor left ventricular ejection fraction, and unsuccessful reperfusion were significantly associated with 30-day mortality. By multiple stepwise logistic regression analysis, dominant LCX, cardiogenic shock, and triple-vessel disease were significant independent predictors of increased 30-day mortality. CONCLUSIONS: LCX infarct-related AMI has its unique clinical features. The presence of dominant LCX and cardiogenic shock were independent determinants of unsuccessful reperfusion, and the presence of dominant LCX, cardiogenic shock, and triple-vessel disease were independent determinants of increased 30-day mortality in this clinical setting.     

Congenital absence of the left circumflex coronary artery associated with acute myocardial infarction: a case report.

Among the congenital anomalies of the coronary arteries, a left circumflex artery (LCX) defect is extremely rare. A 49-year-old man who developed an acute anterior infarction underwent coronary angiography, which revealed complete occlusion of the left main trunk, but the territory usually supplied by the LCX had been perfused by the superdominant right coronary artery. Treatment of the left main trunk by percutaneous coronary intervention produced a favorable result. Accurate evaluation of the principal vessels and the extent of compensatory perfusion is important when diagnosing ischemic heart disease accompanied by anomalous coronary arteries and for choosing the best treatment modality.     

36例回旋支为梗死相关动脉的急性下壁心肌梗死的心电图特点

目的分析回旋支为梗死相关动脉的急性下壁心肌梗死(简称心梗)的心电图表现,总结其心电图特点。方法回顾性分析本院经冠状动脉造影证实回旋支为梗死相关动脉的急性下壁心梗患者36例,分为ST↑Ⅲ<Ⅱ组(n=8),ST↑Ⅲ=Ⅱ组(n=19)和ST↑Ⅲ>Ⅱ组(n=9)三组,分析发病12 h内的18导联心电图特点。比较三组冠状动脉优势型及病变部位。结果 ST↑Ⅲ<Ⅱ组STⅠ、aVL抬高、等电位线、压低的发生率分别为50%,12.5%,37.5%;ST↑Ⅲ=Ⅱ组相应的发生率分别为10.5%,31.6%,57.9%;ST↑Ⅲ>Ⅱ组相应的发生率分别为0,11.1%,88.9%。ST↑Ⅲ<Ⅱ组STV4-6抬高、等电位线、压低的发生率分别为87.5%,0,12.5%;ST↑Ⅲ=Ⅱ组相应的发生率分别为78.9%,21.1%,0;ST↑Ⅲ>Ⅱ组相应的发生率分别为66.7%,0,33.3%。三组患者冠状动脉优势型的比较有差异(P<0.05),三组STV7-9形态、STV3R-5R形态、冠状动脉病变部位无差异(P均>0.05),三组均无房室传导阻滞的发生。结论回旋支为梗死相关动脉的急性下壁心梗ST↑Ⅲ<Ⅱ时常合并STⅠ、aVL抬高,ST↑Ⅲ=Ⅱ、ST↑Ⅲ>Ⅱ时常合并STⅠ、aVL压低;回旋支为梗死相关动脉的急性下壁心梗累及右室时也可表现为ST↑V3R-5R;回旋支为梗死相关动脉的急性下壁心梗不易发生房室传导阻滞。     

The effect of recanalization of the occluded coronary artery in acute myocardial infarction on left ventricular function

In 20 patients with acute myocardial infarction a left ventriculogramwas obtained within 6 h after the onset of chest pain and againduring a follow-up study, 2–3 weeks later. In 17 patientsthe infarct-related vessel (IR V) could be recanalized withselective intracoronary infusion of a thrombolytic agent andwas still patent during the second study. In three other casesthe IR V was already patent during the first angiogram and remainedso at the time of the follow-up study. The ejection fractionof these 20 patients increased from 52 to 56% (P < 0.02). In eight other patients the infarct-related artery could notbe recanalized or was reoccluded at the time of the controlstudy. The ejection fraction of these patients with unsuccessfulrecanalization decreased from 49 to 37% (P<0.001). Analysis of regional function in eight patients with anteriorinfarction and seven patients with inferior infarction, allwith a successful recanalization and persistent patency of theinfarct-related vessels, suggests that improvement of globalejection fraction is only partially due to improvement of regionalpump function in the reperfused ‘infarct zone’ butmay also be caused by enhancement of regional function in otherwall regions or by changes in afterload.     

Acute myocardial infarction of the right coronary artery originating from the distal left circumflex artery

A case of acute myocardial infarction (AMI) of the distal left circumflex, near the origin of an aberrant right coronary artery is presented. Coronary stenting was successfully performed. According to several reports, this anomaly is a common site for coronary atherosclerosis, but this is the first report of AMI.     

急性心肌梗死合并急性左心衰竭临床分析

急性心肌梗死(AMI)合并急性左心衰竭不仅病死率高,而且AMI不易及时诊断导致延误治疗,尤其是非ST段抬高性心肌梗死(NSTEMI)易被忽视,同时合并症多.通过对46例AMI合并急性左心衰竭的病例进行回顾性分析,以期对此类AMI患者的及时诊断及治疗提供参考.……     

Fusiform coronary aneurysm in the left circumflex artery with recurrent myocardial infarction and idiopathic thrombopenia

The authors describe the rare case of a patient with fusiform coronary aneurysm with myocardial infarction in the left circumflex artery complicated by idiopathic thrombopenia. Medical treatment with a combination of warfarin and aspirin could not prevent recurrence of angina pectoris and myocardial infarction, but surgical ligation of the proximal site of the fusiform aneurysm and coronary bypass to the distal site of the fusiform aneurysm prevented further myocardial infarction and angina pectoris.     

Myocardial infarction related to aberrant left circumflex artery

We present a case of lateral wall infarction in the territory of an anomalous circumflex artery without significant stenosis. The unusual location of the infarction suggests a causal relation with the anomalous artery through minor plaque rupture, which may have resulted from mechanical stress.     

Acute myocardial infarction due to left circumflex artery occlusion and significance of ST-segment elevation

Acute occlusion of the left circumflex (LC) artery can be difficult to diagnose. The aim of the present study was to assess the incidence of LC occlusion in patients with acute myocardial infarction (AMI) requiring percutaneous coronary intervention (PCI), the frequency of ST-segment versus non-ST-segment elevation presentation among them, and to correlate the electrocardiographic findings with the outcomes. The clinical characteristics and outcomes of consecutive patients from November 2001 through December 2007 with AMI within 7 days before PCI of a single acutely occluded culprit vessel were included in the present analysis. Of the 1,500 patients, the culprit lesion was located in the right coronary artery, left anterior descending artery, or LC artery in 44.7%, 35.8%, and 19.5% of patients, respectively. Of the 1,500 patients, 72% presented with ST-segment elevation AMI, but only 43% were patients with a LC lesion (n = 127). PCI was significantly less likely (80%, 83%, and 70% for right coronary, left anterior descending, and LC artery, respectively; p < 0.001) to be performed within 24 hours for LC occlusions than for occlusions in the other territories. Among those with a non-ST-segment elevation AMI, the highest post-PCI troponin levels were in patients with a LC artery occlusion (median 1.4, 1.3, and 2.5 ng/ml; p < 0.001). No significant difference was found in the in-hospital mortality (4.4%, 7.4%, and 6.5%; p = 0.66) or major adverse cardiovascular event (9.2%, 13.9%, and 11.6%; p = 0.53) rates for right, left anterior descending, and LC occlusions, respectively. In conclusion, our results have demonstrated that in clinical practice, the LC artery is the least frequent culprit vessel among patients treated invasively for AMI. Patients with LC occlusion are less likely to present with ST-segment elevation AMI and have emergency PCI. The study results suggest that detection of these patients has been suboptimal, highlighting the need to improve the diagnostic approach toward the detection of an acutely occluded LC artery.