Left ventricular thrombi after acute myocardial infarction

Two-dimensional echocardiography was utilized in a prospective study to find the incidence, characteristics and natural history of left ventricular thrombus in 50 consecutive patients with acute myocardial infarction. The overall incidence of thrombosis was 14%; 19% in anterior and 5% in inferior infarction. The thrombus was detected at the apex in 4, along the ventricular septum in 2 and at both these sites in one patient. It was observed 3-10 days after the infarction. Thrombus at the ventricular septum, seen in this study, has not been reported previously in acute myocardial infarction. Development of apical and septal thrombi was significantly associated with akinesis of these sites. Only 2 patients with protruding thrombi had systemic embolism. We conclude that the apex as well as the septum are common sites for thrombosis in patients with severe wall motion abnormalities following acute anterior infarction. Careful observation of these sites during echocardiography may reveal thrombi prone for embolization.     

Left ventricular thrombosis in acute transmural myocardial infarction

To determine the incidence and natural history of left ventricular thrombosis in acute transmural myocardial infarction we performed serial two-dimensional echocardiography in 51 patients. Seventeen patients had inferior infarcts. None of these developed left ventricular thrombosis. The remaining 34 patients had anterior infarcts. Ten of these developed left ventricular thrombus at an average of 4 +/- 2 days after admission. All patients with left ventricular thrombosis had apical akinesia or dyskinesia. Patients with anterior myocardial infarction and akinesia or dyskinesia of the apex are at high risk of developing left ventricular thrombosis. Peak aspartate aminotransferase and lactate dehydrogenase enzyme activity were of little value in identifying this high risk group.     

呈急性心肌梗死样表现的暴发性心肌炎11例

目的分析呈急性心肌梗死样表现的暴发性心肌炎临床特点及治疗方法.方法研究对象符合①45岁以下;②无高血压、高脂血症、糖尿病、吸烟等常见的动脉粥样硬化危险因素;③既往无心绞痛表现;④心肌酶学增高（较正常参考值高2倍以上）;⑤ECG除极相及（或）复极相出现较典型的AMI样改变,即出现异常Q波、ST段抬高或压低;⑥1个月内恢复正常或死亡者.从临床表现、辅助检查及治疗等方面进行分析.结果共11例入选,男性7例,女性4例,平均年龄26岁.8例有前驱感染症状,9例发生心功能不全或室速或严重的房室传导阻滞,10例患者心电图多导联出现异常.根据心超表现分为3型,Ⅰ型3例为心脏结构、心脏收缩功能及舒张功能均无明显异常;Ⅱ型4例为心室腔不增大,但室壁（室间隔或正后壁）增厚,心脏收缩功能及舒张功能均减退,但以舒张功能不全为主;Ⅲ型4例为左心室腔明显扩大,心脏收缩功能明显减退.糖皮质激素对2型效果好.存活7例,经1～2年随访逐渐恢复.结论呈急性心肌梗死样表现的暴发性心肌炎病情重、死亡率高,多有前驱感染症状,常出现多导联心电图异常,依据心超表现的分型对治疗与预后有重要意义.     

Left ventricular free wall rupture during late mechanical reperfusion for acute myocardial infarction

To the editor： Left ventricular （LV） free wall rupture （FWR） is the most fearful complication after acute myocardial infarction （AMI）. We present a rare case that the patient underwent successful late reperfusion but suffered catastrophic irreversible collapse during the procedures.     

Prognostic importance of ventricular extrasystoles in acute myocardial infarction.

Ventricular arrhythmias were recorded in 233 patients in a prospective study of patients with acute myocardial infarction. In over 95% of patients antiarrhythmic therapy was not given until the onset of ventricular tachycardia, ventricular fibrillation, or persistent idioventricular rhythm. There was a mortality of 18% during the patients'' stay in hospital. The most important features of ventricular ectopic activity, which preceded these severe ventricular arrhythmias in the first 48 hr, were multiformity, variation of coupling intervals of larger or equal to 0-1 sec, the R-on-T phenomenon, double ventricular extrasystoles and ventricular bigeminy. The number of a single ventricular extrasystoles per minute was related to the probability of these severe ventricular arrhythmias but to a lesser degree. It was found that if all the patients with the first two prognostic features that if all the patients with the first two prognostic features were removed, the number of single ventricular extrasystoles was not of significant import and the other features were less important. Three-quarters of the severe arrhythmias occurred in the first 24 hr and during this period 60% were preceded by either multiform ventricular extrasystoles or extrasystoles with variable coupling. The importance of these findings in relation to prophylactic therapy is discussed.     

酷似急性心肌梗死的重症心肌炎7例临床分析

目的了解酷似急性心肌梗死的重症心肌炎患者的心电图改变、临床表现,探讨其诊断方法和治疗措施。方法回顾性分析该院2009年11月至2011年6月期间收治的7例急性酷似心肌梗死的重症心肌炎患者的临床资料,男5例,女2例,年龄17～70岁,平均41岁,住院0.5～25d。结果入院时,7例患者心肌坏死标志物明显增高,心电图呈多导联的ST段抬高,住院期间,6例患者经冠状动脉造影检查,1例患者经双源CT冠状动脉血管成像检查排除急性心肌梗死,经积极纠正心力衰竭、大剂量激素冲击治疗等措施,治愈5例,死亡2例。结论部分重症心肌炎患者的心电图改变和临床表现,酷似急性心肌梗死,行冠状动脉造影,有助于明确诊断。治疗关键在于稳定患者的血流动力学状态,激素冲击治疗可能有助于改善症状,缩短住院天数。     

Left ventricular thrombus in patients with acute myocardial infarction:Case report and Caribbean focused update

Despite the well documented benefit of echocardiography in acute coronary syndromes, its wide-scale use in the Caribbean is limited by access, health literacy and affordability. Because of the limited use of echocardiography in the region, routine complications of acute myocardial infarction (AMI) are not fully appreciated and may go unrecognized, further contributing to increased cardiovascular morbidity and mortality. It is therefore necessary to bring focus to this common clinical condition and highlight the clinical utility of echocardiography in facilitating timely and accurate diagnosis. We report here a case of large left ventricular (LV) thrombus in a patient with AMI. Coronary angiography showed completely occluded left anterior descending artery (LAD) with angiographically normal remaining vessels. Immediate anticoagulation was commenced with heparin and overlapped with warfarin. No Primary Angioplasty (PA) was done based on the evidence from occluded artery trial. LV thrombus was completely resolved on echocardiography at three months. No evidence of thrombo-embolism was found during the resolution of LV thrombus.     

酷似心肌梗死的重症病毒性心肌炎的临床分析

目的 探讨酷似心肌梗死的急性重症病毒性心肌炎的诊断和治疗.方法 收集临床表现酷似心肌梗死、经冠状动脉造影示冠脉正常的重症病毒性心肌炎患者38例.分析归纳该病的发病机制、临床特征、治疗及预后.结果 经及时确诊并采取相应治疗后21例患者乏力、胸痛、心悸、气促等症状明显好转,心肌酶、心电图及超声心动图恢复大致正常范围;5例患者阵发性心悸,发作时心电图分别示窦性心动过速、窦性心动过缓、频发室性早搏;2例发作性胸闷、胸痛,心电图示ST-T改变(ST段下移0.1～0.2 mV,T波低平);2例心电图遗留Ⅰ度房室传导阻滞;1例左束支传导阻滞;3例偶发早搏;1例发展为扩张型心肌病;3例急性期死亡.结论 酷似心肌梗死的病毒性心肌炎,其临床表现、心电图、心肌酶改变酷似急性心肌梗死.因此,注重把握临床资料,及时掌握客观诊断依据,积极合理诊治是临床医生值得重视的问题.     

Thiazide-induced hypokalemia. Association with acute myocardial infarction and ventricular fibrillation

Ten of 59 patients (17%) were receiving a thiazide preparation at the time of an acute myocardial infarction and ventricular fibrillation. Hypokalemia was present in seven of eight patients (87%) receiving thiazides, whereas it was observed in only one of 38 patients (2.6%) not receiving these medications. If hypokalemia is present in patients receiving thiazides who have had an acute myocardial infarction, it should be corrected so as to remove this predisposing cause of ventricular fibrillation.     

The prevalence and outcome of ventricular arrhythmias in acute myocardial infarction

One hundred and seventy-two consecutive cases of acute myocardial infarction (MI) admitted to a coronary care unit were studied with regard to ventricular arrhythmias - pre-mature ventricular contractions (PVC), ventricular tachycardia (VT) and ventricular fibrillation (VF). Sixty-seven (39%) patients had ventricular arrhythmias (PCC-VT-VF), of whom 17 (9.8%) had VT and 11 (6.4%) VF. VT and VF, but not total arrhythmias, were more common in anterior infarctions. Fifty-six out of 67 (83.5%) of these patients arrived at Accident & Emergency (A&E) within the first six hours of onset of chest pain. Ten out of 11 (91 %) patients who had VF did so in the first six hours. PVCs were poor predictors of the occurrence of VF (positive predictive value 5.9%). Forty-three patients (84%) who had PVCs did not develop any further arrhythmias. Spontaneous heart rate had no influence on the occurrence of ventricular arrhythmias. Frequent PVCs were more commonly associated with progression to VT and VF. In 30 cases (88%) lignocaine was effective. There was no death due to VT/VF and all responded to drugs and/or cardioversion.     

大鼠急性心肌梗死后心室基质重构的机制研究

目的制作大鼠急性心肌梗死模型,研究心肌梗死后基质重构相关细胞因子的表达,尤其是MMPs、TIMPs及MMPs/TIMPs随梗死时间变化对大鼠心肌基质重构的影响。方法采用冠状动脉结扎法建立大鼠的急性心肌梗死模型。MMPs和TIMPs免疫组化染色、观察心肌梗死后基质的变化及基质金属蛋白酶系统的表达。结果 MMPs和TIMPs免疫组化染色：与假手术组相比较,模型组MMP-2、TIMP-2的表达均随梗死时间的延长而增加,两者在梗死后2周均达高峰,后有所下降,但4周时仍高于假手术组（P〈0.01）,其中MMP-2的表达水平总体上高于TIMP-2的表达水平。结论大鼠急性心肌梗死后,MMP-2、TIMP-2的表达均随梗死时间的延长而增加,两者均于2周达高峰后有所下降,但4周时仍高于假手术组。