Acute myocardial infarction

Transient left ventricular apical ballooning or Takotsubo syndrome (TS) is characterized by transient left ventricular dysfunction, electrocardiographic changes that mimic acute myocardial infarction (AMI), and minimal release of myocardial enzymes, with no evidence of obstructive coronary artery disease. Although prognosis and outcome are relatively good, reported complications include intraventricular thrombi and embolic events. We report an extremely rare case of AMI complicating the early in‐hospital course of a patient with TS. © 2013 Wiley Periodicals, Inc.     

Thrombo-embolic renal infarction in a case of mid-ventricular takotsubo syndrome

Thrombo-embolism is one of the serious complications of takotsubo syndrome (TS). It typically occurs in the classical mid-apical left ventricular ballooning form of TS. This complication has not been reported in cases of left mid-ventricular ballooning type of TS. We describe a 67-year-old woman who presented with 2-3 days of increasing signs and symptoms of heart failure. Echocardiography showed marked hypokinesia/akinesia in the mid-anterior, mid-anterolateral, and mid-inferior wall of the left ventricle and mild hypokinesia in the apical region. There was also hypokinesia of the mid and apical parts of the right ventricle. One day after admission, she developed acute left-sided renal infarction. Left ventriculography and coronary angiography 3 days after admission showed typical left mid-ventricular ballooning with no identifiable coronary lesion. Follow-up echocardiography showed complete resolution of left and right ventricular dysfunction. Takotsubo syndrome with right ventricular involvement complicated with heart failure and left renal embolic infarction was diagnosed. The mechanism of left renal embolic infarction is discussed.     

Coronary collateral circulation

The occurrence and influence of coronary collateral circulation and obstruction of the supplying coronary arteries on left ventricular contractility, prevalence of myocardial infarction, and bicycle exercise ergometer test were studied in a random sample of 286 patients with angiographically documented coronary artery disease. Collaterals appeared increasingly in all three main coronary arteries with grade of obstruction. The highest prevalence of collaterals occurred in stenosis of the right coronary artery (60%), followed by the left descending artery (45%); they occurred least in the left circumflex artery (21%) (p less than 0.001). The frequency of intra-arterial collateral circulation was 42%, 11%, and 12%, respectively (p less than 0.001). With total occlusion of the left anterior descending coronary artery, 22% of the patients had normokinetic anterior and apical left ventricular wall when collaterals were present. More often, the inferior wall showed normal contraction with total occlusion of the right coronary artery and collaterals [52%, p less than 0.001 compared with left anterior descending artery (LAD)]. The prevalence of inferior myocardial infarction was 39%, with collateral circulation to the totally occluded right coronary artery. The respective prevalence of anterior infarction and total occlusion in the left coronary artery was 58% (p less than 0.02). The presence or absence of collaterals had no obvious influence on ST-segment response during bicycle ergometer test. In triple-vessel disease, peak work capacity was better when collaterals to LAD were not jeopardized (427 kpm) than when jeopardized (321 kpm) (p less than 0.02).     

急性ST段抬高性前壁心肌梗死患者的右心室功能分析

目的:评价急性前壁ST段抬高性心肌梗死直接经皮冠状动脉成形术(PCI)患者的右心室收缩和舒张功能变化。方法:分析46例急性前壁ST段抬高性心肌梗死患者[前降支近端完全闭塞者24例(前降支近端闭塞组),前降支远端急性闭塞者22例(前降支远端闭塞组)]直接PCI和35例冠状动脉造影"正常"患者(对照组)的临床、冠状动脉造影和心电图资料。采用二维心脏超声分别测定入选患者的右心室舒张末期容积(RVEDV),右心室收缩末期容积(RVESV),右心室射血分数(RVEF),平均肺动脉压(MPAP),左心室舒张末期容积(LVEDV),左心室收缩末期容积(LVESV),左心室射血分数(LVEF)和心脏指数(CI)。结果:与对照组相比,前降支远端闭塞组的平均肺动脉压无显著性差异(P>0.05),而右心室舒张末期容积和收缩末期容积增大,右心室射血分数降低;左心室舒张末期容积和收缩末期容积增加,左心室射血分数、心脏指数减低(P均<0.01)。与前降支远端闭塞组比较,前降支近端闭塞组的左心室舒张末期容积和收缩末期容积增加(P<0.01),心脏指数和左心室射血分数减少(P<0.01),右心室舒张末期容积收缩末期容积和平均肺动脉压增加(P<0.05～0.01),右心室射血分数降低(P<0.01)。多元线性回归分析表明前降支近端闭塞与右心室射血分数降低(R2=0.38,P<0.01)、右心室舒张末期容积增加(R2=0.410,P<0.01)有较好的相关性。2周后,前降支近端和远端闭塞组的右心室舒张末期容积、右心室收缩末期容积、平均肺动脉压和右心室射血分数无明显差异,而前降支近端闭塞患者的左心室舒张末期容积和收缩末期容积增大,左心室射血分数和心脏指数较低(P均<0.01)。结论:提示前降支近端闭塞可能伴右心室前壁部分心肌梗死导致右心室收缩和舒张功能障碍。     

PFO and paradoxical embolism producing events other than stroke

Background: A patent foramen ovale (PFO) is a risk factor for cerebral events such as cryptogenic stroke, transient ischemic attacks, and migraine headaches. Far less commonly, PFO is associated with non‐cerebral, paradoxical systemic embolic events such as myocardial infarction (MI), renal infarct, and limb ischemia. This report details the incidence of systemic paradoxical emboli at our institution. Methods: 416 patients were referred for evaluation of PFO related conditions from 2001 to 2009. Clinical history and medical records of the patients were reviewed for incidence of cryptogenic stroke, transient ischemic attack (TIA), migraine headache, arterial desaturation, and noncerebral systemic embolism. Results: As the primary presenting symptom, 219 patients had a diagnosis of cryptogenic stroke, 38 patients had migraine headaches, and 80 patients had transient neurologic deficits consistent with a TIA or complex headache. Twelve patients (2.9% of the total population) presented with a presumptive diagnosis of systemic embolism. Eight of these patients had acute MI diagnosed by elevated cardiac biomarkers, electrocardiogram changes, and/or imaging evidence of a left ventricular wall motion abnormality, without evidence of obstructive coronary disease on angiography. Four patients had evidence of peripheral embolism to a systemic artery, including the popliteal artery, ophthalmic artery, and brachial artery. PFO closure was performed in 197 patients (47.4% of the total population), including eight patients in the systemic embolism group. All closure procedures were successful. Conclusion: Although most paradoxical emboli travel to the brain, noncerebral paradoxical embolism is also associated with PFO. In addition to embolism of thrombus, there may be paradoxical passage of vasoactive chemicals that induce intense coronary spasm and myocardial infarction. Diagnosis is often challenging, given the lack of definitive criteria and the need to exclude other potential etiologies. © 2011 Wiley‐Liss, Inc.     

Koronarembolie mit „apical ballooning“ als Komplikation nach elektrischer Kardioversion – Parallelen zur Tako-Tsubo-Kardiomyopathie

CASE STUDY: A case of thromboembolic left anterior descending artery occlusion following electrical cardioversion for atrial fibrillation is described. A 66-year-old female patient presenting with exertional angina pectoris and atrial fibrillation was subjected to coronary angiography, ventriculography and transesophageal echocardiography. No significant coronary stenoses were found, left ventricular systolic function and regional wall motion were normal, and she had no intracardiac thrombi. Direct-current cardioversion was complicated by asystole which was managed by cardiac massage and 1 mg atropine and 1 mg adrenaline intravenously. Shortly afterwards, the patient regained a normal sinus rhythm. She remained hypotensive and developed ST segment elevation over the chest leads. Angiography was repeated and showed apical ballooning and thromboembolic subtotal occlusion of the proximal LAD, which migrated to the periphery and subsequently disappeared with regain of TIMI 3 flow by the end of angiography. 4 months later, a normal left ventricular global and regional function was seen in echocardiography. HYPOTHESIS: At least part of the apical ballooning syndrome patients are a sequel of transient thromboembolic occlusions. METHODS: Therefore, all patients with the diagnosis of coronary embolism in the period from September 2004 to September 2005 were analyzed retrospectively. RESULTS: Further three patients had coronary artery embolism (two females, one male; age 69-76 years). Two patients had apical ballooning, and one showed global hypokinesia (known dilated cardiomyopathy). Cardiac markers were slightly elevated. ST segment elevation was seen in two patients and T-wave inversion in one. All had risk factors for embolization and two had an additional triggering factor. Both cases with apical ballooning had regained a normal ejection fraction at follow-up. CONCLUSION: This case series probably bridges the gap between two as yet separate disease entities, namely the apical ballooning syndrome and coronary emboli. The time factor probably plays the pivotal role in determining whether the apical ballooning alone or also an embolus is seen. It seems possible that some patients presenting with apical ballooning are unrecognized coronary thromboembolic cases.     

In vivo porcine model of reperfused myocardial infarction: In situ double staining to measure precise infarct area/area at risk

Objectives: The aim of this study is to evaluate a catheter‐based porcine model for reperfused myocardial infarction and investigate the appropriate location and duration of the occlusion. Material and Methods: A balloon catheter was placed in the left descending coronary artery (LAD) in 78 swine, and used to occlude the LAD. To evaluate this model, left ventricular ejection fraction (LVEF), infarct size, incidence of ventricular fibrillation (VF), and mortality was compared among three groups: 60‐min proximal LAD occlusion (60P), 60‐min mid LAD occlusion (60M), and 30‐min proximal LAD occlusion (30P). Results: In 72 of the 78 pigs, the procedures were successfully completed. Both mortality and incidence of VF were highest in the 60P group (66.7% and 91.7%, respectively). Myocardial infarction was successfully induced in all 72 animals and in situ double‐staining with Evans blue dye and 2,3,5‐triphenyltetrazolium chloride was performed to delineate area at risk for ischemia and infarcted myocardium. There was no difference in infarct size, expressed as a percentage of the area at risk, between the 60P and 60M groups (49.5% ± 3.9% vs. 45.4% ± 13.3%, respectively). Serial changes in LVEF of the 60M group demonstrated that until 14 days after reperfusion, LVEF improved naturally over time (36.4% ± 6.6% at 24 hr, and 47.3% ± 10.1% at 14 days). Conclusion: This model and methodology could provide a reproducible and consistent infarct size. The current study demonstrated that 60‐min mid LAD occlusion can be the most feasible to serve as a porcine reperfused myocardial infarction model. © 2008 Wiley‐Liss, Inc.     

Proximal RCA occlusion producing anterior ST segment elevation,Q waves,and T wave inversion

An ST segment elevation myocardial infarction (STEMI) that produces anterior ST segment elevation (STE) is typically caused by acute occlusion of the left anterior descending (LAD) artery. Anterior STE, however, may also be caused by acute occlusion of either the proximal right coronary artery (RCA) or the right ventricular marginal branch (RVB). It has been thought that, in contrast to occlusions of the LAD, proximal RCA/RVB occlusion rarely causes Q waves in the right precordial leads. We present a case where a proximal RCA occlusion produced not only anterior STE, but also anterior T wave inversions and anterior Q waves.     

Two successive electrocardiograms of an old male with acute myocardial infarction: What on earth was going on?

A 68‐year‐old male complained of a sudden 2‐h chest pain accompanied by dizziness and diaphoresis. His consciousness lost several times because of ventricular fibrillation attack. Emergent CAG showed proximal left anterior descending (LAD) occlusion, but two previous successive electrocardiograms established diagnoses of non‐ST‐elevation myocardial infarction (NSTEMI) and STEMI respectively, indicating that the patient had experienced acute subtotal occlusion of proximal LAD to total occlusion of the left main coronary trunk (LMT). It is vital to identify de Winter pattern associated with proximal LAD lesion in view of the potential circulatory collapse, fatal arrhythmias and sudden cardiac death from it.     

Transient global left ventricular dysfunction in a localized myocardial infarction related to occlusion of the distal left anterior descending artery

In some patients with acute myocardial infarction (MI), wall motion in the noninfarcted area declines globally despite localized myocardial damage. In most, an infarct-related lesion is the proximal part of the left anterior descending artery (LAD). Previous studies have reported that hypokinesis of remote myocardium may be related to multivessel disease, impaired coronary flow, or coronary flow reserve in nonculprit arteries. This report describes the case of a 53-year-old man who presented with severe global left ventricular (LV) dysfunction after an acute MI associated with distal LAD occlusion. Follow-up echocardiographic examination revealed nearly normalized LV function 5 days after the episode. We discuss a plausible mechanism of dysfunction of noninfarcted myocardium.     

急性心肌梗死合并左心室附壁血栓患者经皮冠状动脉介入术后的抗栓治疗

目的分析急性心肌梗死（AMI）并发左心室附壁血栓（LvT）行经皮冠脉介入治疗（PCI）患者的临床特征及抗栓治疗。方法收集煤炭总医院2005年8月至2012年2月确诊为急性心肌梗死并发左室附壁血栓并行PCI治疗的12例患者的临床资料,对其进行回顾性分析。结果广泛前壁心肌梗死、前壁心肌梗死9例（75％）,左室射血分数低于40％共7例（58％）,冠脉造影检查三支及以上血管病变7例（58％）。6例给予华法林、阿司匹林、氯吡格雷三联抗栓,2例给予西洛他唑、阿司匹林及氯吡格雷三联抗血小板治疗,随访期间血栓均消失。4例双联抗血小板治疗者l例发生脑梗死后加用华法林,3例患者血栓消失,1例血栓机化。12例患者均未出现严重出血现象。结论急性心肌梗死并发左心室附壁血栓并接受PCI治疗患者,充分衡量获益及出血风险,按照个体化原则给予抗栓治疗安全有效。     

Volumineux faux anévrisme de la pointe du ventricule gauche révélant un infarctus du myocarde silencieux

Left ventricular false aneurysms are rare. They are secondary to a myocardial rupture which is contained by adherent pericardium and scar tissue. LV pseudoaneurysm contains no endocardium or myocardium unlike left ventricular true aneurysm. Most cases of LV pseudoaneurysm are related to acute myocardial infarction in inferior or posterior wall. We report a case of a 56-year-old man with a medical history of chronic cigarette smoking, dyslipidemia, and obesity. The patient had no myocardial infarction before. He was admitted for evaluation of important shortness of breath at effort without chest pain for 5 months. Physical exam find an enlarged left ventricular. The electrocardiogram revealed Q waves and ST segment elevation in leads V1 to V6. Transthoracic echocardiogram showed a large thrombosed apical left ventricular false aneurysm, severe left ventricular dysfunction, which were confirmed by cardiac magnetic resonance imaging, this exam also showed no viability in the mid left anterior descending coronary artery territory. The coronary angiography showed an occlusion of the mid left anterior descending coronary artery and a stenosis of the first diagonal artery. The patient was offered a surgical aneurysectomy with coronary artery bypass. The surgery was successful with amelioration of symptoms. We present a rare case of a giant false left ventricular aneurysm complicating a silent myocardial infarction in the anterior wall. The diagnosis is made by cardiac echocardiogram and cardiac magnetic resonance imaging. Because of the important risk of rupture, the surgical treatment is required.     

Acute cardiac sympathetic disruption and left ventricular wall motion abnormality in takotsubo syndrome

Abstract

Takotsubo syndrome (TS) is characterized by a unique pattern of transient circumferential left ventricular wall motion abnormality (LVWMA). The LVWMA in TS may be localized to the apical, mid-apical, mid-ventricular, mid-basal or basal regions of the left ventricle. Focal and generialized (global) LVWMA have also been reported. In the acute phase of TS, the hyperkinetic valve-like motion of the basal segments and/or the hyperkinetic slingshot-like motion of the apical segments combined with the firm stunned a-, hypokinetic segments result in a conspicuous left ventricular ballooning during systole. The LVWMA in TS follows most probably the local cardiac sympathetic nerve distribution and caused by local cardiac sympathetic disruption and noradrenaline spillover.     

Left ventricular thrombosis and arterial embolism in acute anterior myocardial infarction

Abstract. To study left ventricular thrombus (LVT) formation and arterial embolism (AE), 106 consecutive patients with a first acute anterior myocardial infarction (AAMI) underwent two-dimensional echocardiography before discharge. Repeated assessments for detection of AE were performed. Patients were non-randomly allocated to either no heparin, low-dose heparin or high-dose heparin. LVT was found in 25 (26.9%) of 93 patients with technically satisfactory echocardiograms. Left ventricular (LV) wall motion impairment (P = 0.0017) and treatment with either heparin or low-dose heparin (P = 0.0019) were independent predictors of LVT formation. AE, all strokes, occurred in 10 patients (9.4%) and was strongly associated with high age (P = 0.0013). In conclusion. LVT and AE are frequent complications to AAMI. LV wall motion impairment predisposes for LVT and low-dose heparin seems not to prevent these complications.     

Spontaneous coronary artery dissection and takotsubo syndrome: The chicken or the egg causality dilemma

Acute coronary syndrome (ACS) including spontaneous coronary artery dissection (SCAD) has been reported to trigger its own clinical twin takotsubo syndrome (TS). The pathogenetic association between SCAD and TS remains to be elucidated. The two diseases afflict predominantly women and both conditions may be triggered by an emotional stress factor and an unusual extreme physical exercise. Herein, we describe a case of 54‐year‐old woman presenting with ACS caused by an obtuso‐marginal SCAD. Concurrently, the patient had typical clinical features and course of mid‐apical pattern of TS. The causal link between the two conditions is discussed. © 2017 Wiley Periodicals, Inc.     

Site of myocardial infarction. A determinant of the cardiovascular changes induced in the cat by coronary occlusion.

The influence of site of acute myocardial infarction on heart rate, blood pressure, cardiac output, total peripheral resistance (TPR), cardiac rhythm, and mortality was determined in 58 anesthetized cats by occlusion of either the left anterior descending (LAD), left circumflex or right coronary artery. LAD occlusion resulted in immediate decrease in cardiac output, heart rate, and blood pressure, an increase in TPR, and cardiac rhythm changes including premature ventricular beats, ventricular tachycardia, and occasionally ventricular fibrillation. The decrease in cardiac output and increase in TPR persisted in the cats surviving a ventricular arrhythmia. In contrast, right coronary occlusion resulted in a considerably smaller decrease in cardiac output. TPR did not increase, atrioventricular condition disturbances were common, and sinus bradycardia and hypotension persisted in the cats recovering from an arrhythmia. Left circumflex ligation resulted in cardiovascular changes intermediate between those produced by occlusion of the LAD or the right coronary artery. Mortality was similar in each of the three groups. We studied the coronary artery anatomy in 12 cats. In 10, the blood supply to the sinus node was from the right coronary artery and in 2, from the left circumflex coronary artery. The atrioventricular node artery arose from the right in 9 cats, and from the left circumflex in 3. The right coronary artery was dominant in 9 cats and the left in 3. In conclusion, the site of experimental coronary occlusion in cats is a major determinant of the hemodynamic and cardiac rhythm changes occurring after acute myocardial infarction. The cardiovascular responses evoked by ligation are related in part to the anatomical distribution of the occluded artery.     

Correspondence between left ventricular 17 myocardial segments and coronary arteries.

AIMS: The last guidelines recommend a standardized 17-segment model for tomographic imaging of the left ventricle. The aim of this study is to analyse the correspondence of the 17 left ventricular segments with each coronary artery by myocardial perfusion SPECT studies. METHODS AND RESULTS: Fifty patients selected for percutaneous revascularization of one coronary artery [24 left anterior descending (LAD), 15 right coronary artery (RCA), and 11 left circumflex (LCX)] were included. The (99m)Tc-labelled compound was injected immediately after the inflation of the balloon during percutaneous coronary angioplasty. At least 90 s of complete occlusion time was required. Maximal contour of regions of hypoperfusion corresponding to each coronary artery occlusion were delineated over the polar map of 17 segments. Nine segments corresponded to only one coronary artery: eight to LAD (basal anterior, basal anteroseptal, mid-anterior, mid-anteroseptal, apical anterior, apical septal, apical lateral, and apex) and one to LCX (basal anterolateral). Basal inferoseptal, mid-inferoseptal, and apical inferior segments could correspond to LAD or RCA. Basal inferior, basal inferolateral, mid-inferior, and mid-inferolateral segments could correspond to RCA or LCX, whereas the mid-anterolateral segment could correspond to LAD or LCX. CONCLUSION: The most specific segments (anterior, anteroseptal, and all apical segments except the infero-apical) correspond to LAD but no segment can be exclusively attributed to the RCA. Inferoseptal segments can be attributed to LAD or RCA, inferior and inferolateral segments to RCA or LCX, and mid-anterolateral segment to LAD or LCX.     

Acute Posterior-inferior Myocardial Infarction Caused by Total Occlusion Distal to the Apex of the Hyperdominant Left Anterior Descending Artery

A 77-year-old woman was admitted to our hospital with severe ongoing chest pain. Electrocardiography showed ST-segment elevation in the inferior leads and tall R waves in leads V1-2. Posterior-inferior myocardial infarction was diagnosed. Emergent coronary angiography (CAG) revealed the wrap-around left anterior descending artery (LAD) with total occlusion distal to the cardiac apex. She underwent percutaneous coronary intervention (PCI). Despite difficulty navigating the long and tortuous LAD, we successfully performed reperfusion of the wrap-around LAD. CAG post-PCI showed the posterior descending artery arising from the LAD, described as hyperdominant LAD.     

Percutaneous Coronary Intervention for Acute Myocardial Infarction in a Single Coronary Artery Anomaly

We report on a case of an adult male patient with previously unknown coronary anomaly and acute myocardial infarction in the territory of the left anterior descending artery (LAD). The coronary angiography showed a single coronary artery with intertruncal course, arising from the right coronary sinus, and thrombotic occlusion of the LAD. Successful transradial percutaneous coronary intervention was done with implantation of an intracoronary stent in the occluded artery. The postprocedural course was complicated by ventricular tachycardia, congestive heart failure, and mild transient renal failure. In conclusion, transradial percutaneous coronary intervention is safe and feasible in rare coronary artery anomalies even in an emergent setting. The finding of an anomalous coronary artery should not be a reason to decline performing coronary intervention. Copyright © 2009 Wiley Periodicals, Inc.     

Visualization of isolated conus artery as a major collateral pathway in patients with total left anterior descending artery occlusion

To examine the existence of isolated conus artery (ICA) as a source of collateral circulation, we selectively visualized the ICA in patients with left anterior descending coronary artery (LAD) occlusion using a no. 5 French catheter. One hundred and fifty patients with a total LAD occlusion were selected from 639 consecutive patients who had diagnostic coronary angiography during an 18-month period; the ICA was found in 45 patients. Among these patients, 30 showed the ICA as a collateral vessel supplying the distal LAD. In nine of these patients, conventional left and right coronary angiography did not reveal any other significant collateral vessels, and the distal LAD was perfused mainly by the collaterals from the ICA. No serious complications such as ventricular fibrillation or myocardial infarction occurred during these procedures. These results indicate that the selective ICA visualization is clinically important when conventional left and right angiography does not demonstrate collaterals to the obstructed LAD.