Reversible clopidogrel resistance due to right ventricular myocardial infarction: risk factor of recurrent stent thrombosis?

A 63-year-old male Patient was admitted to the intensive care unit due to acute inferior myocardial infarction with right ventricular dysfunction. He received a loading dose of clopidogrel (600 mg) and aspirin (500 mg) and was immediately revascularized by reopening of the proximal right coronary artery (RCA) and implantation of a bare metal stent. After primary successful intervention the patient suffered from thoracic pain on day 5 of admission. The ECG indicated reinfarction. The proximal RCA was again re-opended by PTCA alone. The following day the patient suffered again from thoracic pain with ST-elevation in the inferior leads, this time complicated by additional total AV-blockade. The angiography showed another time a thrombotic occlusion of the initially implanted stent. He received another intervention with implantation of additional two baremetal stents, an aortic counter-pulsation and a temporary two-chamber pace maker. Tirofiban was administered for 24 h and the IABP was withdrawn after 60 h. The patient was discharged on Aspirin 300 mg/d, Clopidogrel 150 mg/d and Enoxaparin 40 mg/d. Six weeks later the patient demonstrated an improved right ventricular function (TAPSE 18 mm), liver enzymes were normal, and inhibition of platelet aggregation by clopidogrel (150 mg/d) was sufficient. In conclusion this implies that the reversible “clopidogrel-resistance” might have been due to congestion and reduced metabolism due to right ventricular infarction.     

Combined aspirin and Clopidogrel resistance associated with recurrent coronary stent thrombosis

Summary We report about a 72–year–old woman who was admitted to our hospital because of an acute ST–elevation myocardial infarction (STEMI). At admission, she received a loading dose of 300 mg Clopidogrel and 500 mg aspirin (ASA) prior to angioplasty with stenting of a 90% diameter stenosis of the proximal right coronary artery. After intervention, 75 mg Clopidogrel and 300 mg ASA OD were continued. Three days later, she developed a recurrent acute STEMI due to stent thrombosis and a second stent implantation was performed. The dose of Clopidogrel and ASA remained unchanged. Three days later, the patient suffered a third STEMI due to a restent thrombosis and additional stent implantation was performed. The dose of Clopidogrel and ASA was increased to 75 mg BD and 500 mg OD. Platelet function analysis and aggregation studies demonstrated dose–independent ASA resistance. ADP–induced aggregation showed a short–term platelet inhibition with subsequent rapid normalisation, thus suggesting Clopidogrel resistance. Therefore, the treatment was changed to coumadin and ASA 100 mg OD. Since then, the patient has been clinically stabile. Our case indicates for the first time the existence of a subgroup of patients with combined Clopidogrel and ASA resistance. We conclude that identification of these patients is required and alternative therapeutic options have to be considered.     

Monitoring the patient with acute myocardial infarction

Cardiac monitoring is a vital component in the management of the patient with AMI. Knowledge of the age, location, and extent of an MI and effective use of continuous cardiac monitoring will aid the nurse in anticipating, identifying, and treating potential complications.     

Amphetamine-related acute myocardial infarction due to coronary artery spasm

A 27-year-old man developed acute myocardial infarction after intravenous amphetamine use. A coronary angiogram showed plaques in the mid-portion of the left anterior descending artery which developed coronary artery spasm after administration of intracoronary ergonovine. The findings in this case suggest that these coronary artery plaques played a role in the endothelial dysfunction resulting from amphetamine use, and that induction of coronary arterial spasm was the likely mechanism of amphetamine-related acute myocardial infarction.     

老年急性心肌梗死支架植入患者的护理

近年来,经皮冠状动脉(简称冠脉)介入治疗(percutaneous coronary intervention,PCI)广泛应用于急性心肌梗死(AMI)的救治中,尽管氯吡格雷和阿司匹林联合抗血小板治疗减少了术后并发症的发生,但术后再狭窄及不良心脑事件等仍有发生.本研究对2003年5月-2005年12月因急性心肌梗死在我院成功接受冠脉支架植入术的68例老年患者进行了随访观察,旨在明确老年急性心肌梗死支架植入术后的远期疗效,为临床护理此类患者提供依据,现报道如下.     

国产支架在急性心肌梗死患者急诊冠状动脉介入治疗中的安全性和疗效

目的探讨急性心肌梗死患者中置入国产支架的安全性及疗效。方法共有36例急性心肌梗死患者人选。年龄(57±9．7)岁的36例患者均顺利完成急诊PCI及支架置人。其中前璧心肌梗死18例；下壁心肌梗死14例；高侧壁心肌梗死2例；后壁合并右室心肌梗死2例。合并糖尿病12例,高血压20例．吸烟18例。结果36例患者置入国产支架37枚,术中未出现并发症,血流均达到TIMI3级。7d时20例患者造影随访未见支架内血栓形成,血流维持TIMI3级。结论国产支架用于急性心肌梗死是安全有效的。     

Coping and adjustment to illness in the acute myocardial infarction patient

This study examined the coping strategies of acute myocardial infarction (MI) patients one month following discharge from the hospital. Problem- and emotion-focused coping strategies were identified in 30 acute MI patients and correlated with psychologic, social, and physiologic adjustment variables. Individuals who used more problem-focused coping than emotion-focused coping were found to have better social (p less than .005) and psychologic adjustment (p less than .05). Individuals who had more physiologic symptoms were found to have poorer psychologic adjustment. Early identification of those patients at risk for psychosocial distress is paramount to maximize the patient's coping process and prepare the patient psychologically prior to hospital discharge.     

Pulmonary infarction due to vascular stent migration

The case of a patient who developed pulmonary infarction after a vascular stent migrated to her pulmonary artery is presented. Stent migration is a known complication of vascular stents. The incidence is reported to be as low as 3%. Cases have been reported of successful retrieval of the stents. There are also reports of the stents being left in place without attempts to retrieve them, due to lack of symptoms. In this case, we opted to monitor the patient, despite the presence of pulmonary infarction. She appears to be tolerating the stent without any further complications.     

Therapeutic procedures in the emergency department patient with acute myocardial infarction

Life-threatening cardiac arrhythmias and other peri-infarct complications are often unexpected and commonly present with little warning. The therapeutic procedures reviewed often require immediate implementation and should be second nature to any physician involved in the management of patients with an AMI.     

Iatrogenic magnesium overdose in a patient with suspected acute myocardial infarction

A case of iatrogenic, parenteral overdose of magnesium sulfate in a patient with suspected acute myocardial infarction is presented. A 73-year-old man presented with a history and physical examination consistent with suspected acute myocardial infarction and congestive heart failure. During the patient's treatment in the emergency department (ED), the physician ordered 2 g magnesium sulfate intravenously. The nurse mistakenly administered “two amps” (two 25-g single-dose vials) of magnesium sulfate intravenously. The patient developed bradycardia, hypotension, and apnea during the infusion. Although the use and inadvertent misuse of magnesium salts in obstetrics is well known, iatrogenic overdose in a patient with cardiac indications for magnesium has not been previously reported. Personnel responsible for the administration of medications in the ED must be educated about the dosing regimens and adverse effects associated with magnesium.     

糖尿病患者合并急性心肌梗死的窦性心率震荡分析

目的探讨2型糖尿病患者合并急性心肌梗死时窦性心率震荡（HRT）的可能变化及其临床意义。方法选择2型糖尿病合并心肌梗死患者47例（1组）、单纯心肌梗死患者40例（2组）、单纯2型糖尿病患者40例（3组）和对照组40例（4组）作为研究对象。4组均行24小时动态心电图（DCG）检查,分析单次室性期前收缩（PVS）后HRT的初始值（TO）、斜率（TS）以及TO和TS异常的发生率。结果 1、2、3组TO、TS值明显异常,分别为0.49（0.86）%和（4.31±3.64）ms/R-R、0.33（0.57）%和（8.83±7.55）ms/R-R、0.16（0.39）%和（10.77±8.39）ms/R-R,与4组比较差异均有统计学意义（P〈0.01）,1、2组的TO、TS值与3组比较差异均有统计学意义（P〈0.01）,1组与2组比较差异亦有统计学意义（P〈0.05,P〈0.01）。4组TO及TS异常发生率分别为1组59.5%、63.8%,2组47.5%、52.5%,3组35.0%、37.5%和4组7.5%、10.0%,1、2、3组TO、TS值异常率较4组明显升高（P〈0.01）,1、2组TO、TS值异常率较3组明显升高,1组TO、TS值异常发生率增高最明显。结论青中年糖尿病合并心肌梗死患者HRT现象明显减弱,同时HRT异常率增高较明显。HRT可作为临床上青中年糖尿病合并心肌梗死患者预后判断的重要指标。     

替罗非班联合氯吡格雷对老年急性ST段抬高型心肌梗死的治疗效果分析

目的探讨替罗非班联合氯吡格雷治疗老年急性ST段抬高型心肌梗死的治疗效果。方法采用前瞻性临床对比研究,选取2017年10月至2018年10月简阳市人民医院收治的138例老年急性ST段抬高型心肌梗死患者作为研究对象,按照随机数字表法分为两组:对照组和观察组,每组各69例。两组患者入院后均给予常规溶栓治疗,对照组患者在此基础上给予口服硫酸氢氯吡格雷片,观察组患者在对照组的基础上给予替罗非班注射液,两组均治疗14 d。治疗后,比较两组患者的临床疗效,以及心肌酶指标[肌钙蛋白(c Tn I)、肌酸激酶同工酶(CK-MB)、乳酸脱氢酶(LDH)]、血小板活化功能指标[单核细胞血小板聚集体(MPA)、血小板α颗粒表面膜糖蛋白(CD62P)、溶酶体膜糖蛋白(CD63)]、炎性因子[超敏C反应蛋白(hs-CRP)、肿瘤坏死因子-α(TNF-α)、白细胞介素-6(IL-6)]水平的变化及心血管事件的发生情况。结果治疗后,观察组患者的总有效率(92. 75%)明显高于对照组(76. 91%),差异具有统计学意义(P <0. 05)。治疗后,观察组患者的c Tn I由(8. 37±1. 72)μg/L降至(4. 55±0. 93)μg/L、CK-MB由(80. 51±16. 29) U/L降至(39. 76±7. 72) U/L、LDH由(122. 64±26. 86) U/L降至(73. 52±15. 67) U/L,且观察组明显低于对照组,差异均有统计学意义(P <0. 05)。治疗后,两组患者的MPA、CD62P及CD63水平均明显降低,且观察组明显低于对照组,差异均有统计学意义(P <0. 05)。治疗后,两组患者的hs-CRP、TNF-α及IL-6水平均显著降低,且观察组明显低于对照组,差异均有统计学意义(P <0. 05)。治疗期间观察组和对照组患者的心血管事件总发生率分别为13. 04%、27. 54%,观察组明显低于对照组,差异具有统计学意义(P <0. 05)。结论替罗非班联合氯吡格雷治疗老年急性ST段抬高型心肌梗死临床效果显著,可明显抑制患者血小板活性,降低炎症反应,改善患者心功能,降低心血管事件发生率,值得在临床推广应用。     

双源CT对急诊经皮冠状动脉介入治疗后冠状动脉支架通畅性及左心室功能的评价

目的：观察双源CT（DSCT）评价急性心肌梗死患者急诊PCI术后支架通畅性和左心室功能。方法2010年1月至2011年12月入选的急性心肌梗死且行急诊PCI患者46例,共植入火鸟第二代支架52枚,支架直径在3.0～4.0 mm范围内,于急诊PCI后第12月末分别行冠状动脉造影及DSCT检查（两者相隔5～7 d）。利用DSCT分析冠状动脉支架是否存在再狭窄,应用左心室功能分析软件测定和计算左心室功能相关指标：舒张末期容积（EDV）,收缩末期容积（ESV）,每搏输出量（SV）,左心室射血分数（LVEF）。同时利用超声心动图测量上述指标。结果（1）46例患者中,冠状动脉造影显示共有3例患者出现支架再狭窄,此3例患者中有2例被DSCT正确判断;共有43例患者支架无狭窄,此43例患者中有41例被DSCT正确判断。和冠状动脉造影相比,DSCT 的敏感性为66.67%,特异性为95.34%,准确性为93.47%,阳性预测值为50%,阴性预测值为97.6%。（2）在52枚支架中,冠状动脉造影显示共有5枚支架出现再狭窄,此5枚支架有3枚被DSCT正确判断,共有47枚支架无再狭窄,此47枚支架有44枚被DSCT正确判断。相比冠状动脉造影,DSCT的敏感性为60%,DSCT的特异性为93.61%,DSCT的准确性为90.38%,阳性预测值为50%,阴性预测值为95.65%。（3）超声心动图和DSCT测定的EDV、ESV、SV、LVEF无统计学差异。结论双源CT能评价用于急性心肌梗死患者急诊PCI支架通畅性和左心室功能。