Acute anterior wall myocardial infarction complicated by cardiogenic shook in an elderly female patient

(Institute of Geriatric Cardiology, Chinese PLA General Hospital, Beijing 100853, China)

Case presentation

A 73-year-old female was admitted into the Institute of Geriatric Cardiology, Chinese PLA General Hospital because of sudden chest pain accompanied with nausea and vomiting for 15 hours. At 3:00 on August 14th, 2011, the patient suddenly suffered from severe chest pain accompanied with perspiration, nausea, vomiting, and cold extremities, but she was under normal conscious level. In the emergency room, electrocardiogram(ECG) at 18:00 showed ST segment elevation on the precordial leads. Cardiac biochemical markers increased proportionally. The patient had a history of hypertension for 10 years which was poorly controlled, chronic bronchitis for several years, cerebral ischemia attack one month ago, and diarrhea one day before admission. She denied any history of smoking, alcohol drinking, or illicit drugs use.

On admission examination, the blood pressure was 90/70mmHg and the respiratory rate 20 breaths per minute. Both lungs were clear with moist rales. Heart rate was 133 beats per minute. Percussion revealed a dull sound. A grade 2-3/6 diastolic murmur could be heard at the left second intercostal space(ICS). Dorsalis pedis artery pulse was weak. Transthoracic echocardiogram showed a left ventricular ejection fraction (LVEF) of 43%, a normal-size left ventricular cavity, moderate dysfunction involving the septal and anterior, lateral and apex segments of the midportion, the thinned left ventricle, and ventricular aneurysm at the apex. Chest radiogragh showed pulmonary infection.

Considering the diagnosis of acute ST-elevation myocardial infarction (STEMI) and cardiogenic shock, the patient received emergency intra-aortic balloon bumping(IABP) implantation and percutaneous coronary intervention(PCI). Cardioangiography (CAG) showed occlusion of the left anterior descending (LAD) artery right after the first diagonal opening. There was poor collateral flow to the distal LAD artery. The ostial diagonal branch presented a localized stenosis of about 90%. The left circumflex coronary artery and its branches appeared to be free of obstruction. Considering LAD as the culprit vessel, one stent was implanted in the middle LAD.

Medication therapy was administrated, including anti-platelet, anti-coagulation, nitrate, statin, liver and renal protection, anti-infection and nutritional support. Diuretics were given intermittently to control the input and output. Dopamine was given intravenously to maintain the blood pressure. Because of her poor heart function, high heart rate and frequent ventricular premature beats, cedilanid and amiodarone were also administrated. On August 16th, tracheal cannula placement and mechanical ventilator support were performed as a result of repeated acute left heart failure, pulmonary infection and liver and renal dysfunction. Sodium nitroprusside, imipenem and cilastatin were administrated, while amiodarone stopped. Intake and output were also controlled. After all these treatment, the liver and renal function improved, intermittent respirator suspension training went smooth and heart function improved. The platelet account presented a slight decrease, and IABP balloon induced platelet injury was highly suspected. Tracheal cannula and IABP were removed on the 22ndand 24thin sequence. Consequentially, respiratory rate increased later, accompanied with continuous low-blood-pressure state which even high dose of dopamine could barely correct. On the 26th, acute left heart failure attacked. ECG monitor suggested junctional rhythm and frequent ventricular premature. The patient lost consciousness. Digitalis intoxication was highly suspected. Laboratory examination showed serum level of digoxin ＞4ng/dl, confirming digitalis intoxication. Digitaloid medications were forbidden immediately. Tracheal intubation and IABP implantation were performed for the second time. Epinephrine, norepinephrine and high dose of dopamine,, were all given to keep the blood pressure stable. Respiratory acidosis was corrected after sodium bicarbonate intravenous administration. The patient regained consciousness. Between November the 6thand November the 16th, repeated intermittent ventilator weaning all failed and IABP counterpulsation failed to maintain the blood pressure. Heparin-induced thrombocytopenia (HIT) developed, so did continuous hyperpyrexia, pulmonary infection aggravation and frequent ventricular premature. The patient was under a severe condition persistently. At 19:00, November the 17th, 2011, blood oxygen saturation suddenly dropped to 50%-70%, heart rate 140-150 beats per minute, blood pressure 70/50mmHg. Pure oxygen was given, accompanied with epinephrine and bicarbonate injection. Her family members rejected the rescue treatment with cardiopulmonary resuscitation (CPR) and electric defibrillation, the patient was confirmed dead at 19:40.

Clinical discussions

:This elderly female was diagnosed with acute STEMI in the anterior wall and cardiogenic shock. Considering the hospital admission delay, together with liver and kidney dysfunction, as well as pulmonary infection, the patient was in severe condition and had a great risk of death. As for treatment, the following points should be considered. (1) Digitalis intoxication. Regarding the cardiac dysfunction, higher heart rate and frequent ventricular premature, digoxin and cedilanid were administrated. Because digitalis was in high dose, the plasma concentration should be monitored frequently. In this case, ECG revealed junctional rhythm, which was highly due to digitalis intoxication. (2) Infection. This patient presented with cardiogenic shock, a long history of bed rest, poor nutritional status, weak cough, tracheal intubation, previous history of chronic bronchitis. In addition of IABP implantation, deep-vein catheterization and urinary catheter placement, she was in a great risk for catheter associated infection. The patient¢s body temperature, blood routine test, chest radiogragh, clinical signs, especially the result of sputum culture should all be taken into consideration in antibiotics application.

: Multi-organ dysfunction is a common problem in AMI patients after PCI, mostly according to illness progression and iatrogenic reasons. In this case, cardiogenic shock had been present before admission. With a low-blood-pressure state for several hours, hypoperfusion developed, which manifested as paleness, cold extremities, weak dorsal pedis artery pulse, hepatic congestion, pulmonary venous congestion, and renal dysfunction. All these suggested severe multi-organ dysfunction which led to a poor prognosis. Clinical doctors should pay much more attention to iatrogenic liver injury, acute kidney injury (AKI), digitalis intoxication and HIT. Liver injury was usually associated with liver disease history, cardiac dysfunction, congestive & ischemic hepatopathy and iatrogenic liver injury(intravenous administration of amiodarone). Acute kidney injury can be induced not only by hypoperfusion, but also by radiographic contrast application. Patient with repeated left heart failure usually received high dose of digitaloid drugs orally and intravenously, so digitalis intoxication should be carefully monitored by close observation of clinical symptoms, electrocardiogram and plasma digoxin concentration. For a post-PCI patient with cardiac dysfunction and IABP implantation, the platelet count decreased, which may be related to either HIT or IABP balloon induced mechanical platelet injury. In this case, platelet count displayed no change under IABP support and after IABP removal, while it increased greatly after heparin was replaced by argatroban, so HIT was strongly suggested.

: For AMI patients with cardiac dysfunction, some factors predicted poor prognosis, including advanced age, pulmonary infection, liver and renal dysfunction, large infarction area, less survival myocardium, low LVEF, multiple post-infarction complications, history of adverse cerebral events,. Considering these factors, in addition to the im­patience aspects in her characteristics and delayed revascularization time, this patient was more likely to have poor prognosis and in-hospital death. Several dilemma made the treatment even more complicated. Firstly, failure in removing IABP suggested severe myocardial stunning which necessiates prolongation of mechanical support, while considering pulmonary infection and potential catheter-related infection, an earlier removal of IABP was undoubtedly preferable. Maintenance of blood pressure was another dilemma. Vasoconstriction agents may increase afterload and labor the myocardium, while coronary hypoperfusion may occur if vasoconstriction agents were not applied. Additionally, high dose of dopamine improved the blood pressure but constricted peripheral vessels simul­taneously which induced multi-organ hypoperfusion consequently, especially liver and kidney. Meanwhile, small dose of sodium nitroprusside dilated peripheral vessels to improve multi-organ hypoperfusion, but left blood pressure maintenance a great problem. All these made it difficult to balance between the advantage and disadvantage of every treatment, which increased the risk of poor prognosis.

In brief, cardiac dysfunction complicated AMI patients are of high risk and poor prognosis. Iatrogenic multi-organ injuries should be avoided by every means possible. More attention should be paid to drug use, including indications, contraindications, therapeutic effects, and adverse reaction. Based on clinical symptoms, signs and laboratory tests, treatment strategy should be adjusted by comprehensively balancing between the advantages and disadvantages. Prognosis evaluation plays important roles in keeping abreast of the disease progress, performing the treatment actively and informing the patient’s family members effectively. It is strongly recommended that clinical doctors give intensive attention to this kind of patients in hope of accumulating experience, increasing survival rate, and improving the patient’s long-term outcome.

(Translator: GAO Lei)

高龄女性急性广泛前壁心肌梗死合并心源性休克死亡1例

1 病例摘要

患者因“发作性胸痛伴恶心呕吐15h ”收入解放军总医院老年心血管病研究所病房。2011年8月14日3:00患者无明显诱因出现明显胸痛, 伴恶心、呕吐、大汗、四肢湿冷, 无意识丧失, 18:00就诊于我院急诊, 心电图提示胸前导联ST段抬高, 心肌损伤标志物明显成比例升高。患者既往高血压病史10年, 目前控制不佳; 慢性支气管炎病史多年; 1个月前发生脑梗死; 入院前一天腹泻。既往无吸烟、饮酒、违禁药物应用史。

入院查体: 体温36.5℃, 血压90/70 mmHg, 双肺呼吸音清, 双肺底可闻及少量湿性啰音。心率133次/min, 心音低钝, 胸骨左缘第二肋间可闻及2-3/6级舒张期杂音, 双侧足背动脉搏动减弱。超声心动图提示: 左室射血分数（left ventricular ejection fraction, LVEF）43%, 室间隔中段至心尖段、左室前壁、侧壁运动减弱, 室壁变薄, 心尖部室壁瘤形成, 矛盾运动, 未见明显心包积液。胸片提示双肺炎症。

考虑急性前壁ST段抬高型心肌梗死、心源性休克诊断明确, 急诊行主动脉内气囊泵疗法（intra-aortic balloon bumping, IABP）和经皮冠脉介入术（percutaneous coronary intervention, PCI）。造影提示前降支发出第一对角支后完全闭塞, 未见侧枝供应, 第一对角支开口受累, 局限性狭窄90%, 回旋支未见明显狭窄, 右冠弥漫性病变。考虑前降支为罪犯血管, 于前降支近中段狭窄处植入支架1枚。

术后予抗血小板、抗凝、扩冠、调脂、改善肝、肾功能、抗感染、解痉平喘、营养支持等治疗, 间断利尿, 多巴胺持续泵入维持血压。考虑患者心功能差, 心率快, 频发室性早搏, 予间断西地兰静脉推注、胺碘酮静脉滴注。……