Myocardial Infarction and Complete Heart Block

The clinical and electrocardiographic records of 20 patients with complete A-V block due to acute myocardial infarction have been analyzed. This study indicated that patients with an inferior wall myocardial infarction had, most commonly, a block above the bifurcation. The block was transitory, the patients had no Stokes-Adams attacks and the outcome was good. None of our patients required artificial pacing. On the other hand, patients with an anteroseptal myocardial infarction suffered from a bilateral bundle branch block (below the bifurcation). They had severe Stokes-Adams attacks and they all required artificial pacing. The destruction of the conducting system was extensive and the outcome was poor. Five out of seven patients treated with artificial pacing recovered the A-V conduction through the left bundle within a few days. However, in spite of this they all died.From this small series clearly defined clinical and electrocardiographic features can be identified in two different groups of cases.     

Increased Sensitivity to Heparin Following Acute Myocardial Infarction

In vivo increased sensitivity to heparin has been demonstrated in patients following an acute myocardial infarction. An intravenous injection of 10,000 units of heparin was given to each of 18 patients with recent myocardial infarction in order to compare them with 17 patients who were not suffering from any acute illness. The changes in whole blood clotting time, recalcified plasma clotting time and prothrombin time were greater and more prolonged in the patients with recent myocardial infarction. Of the three tests, the one-stage prothrombin time provided the simplest and the most precise measurement of heparin sensitivity. The reason for this was not clear: it is possible that it is related to shock and congestive heart failure which were complications of the clinical course following myocardial infarction.     

Preservation of pre-excitation despite acute myocardial infarction complicated by complete heart block.

In a 53-year-old man with ventricular pre-excitation (normal PR interval, QRS interval of 0.12 seconds and delta-waves) acute inferior wall myocardial infarction was complicated by, successively, first-degree atrioventricular block, second-degree atrioventricular block (Wenckebach type) and complete heart block. The QRS pattern of pre-excitation was preserved throughout these events. The classification of ventricular pre-excitation is reviewed and the correlation between the various electrocardiographic patterns (the Wolff-Parkinson-White syndrome and its variants and the Lown-Ganong-Levine syndrome) and the anomalous conduction pathways of Kent, James and Mahaim are discussed. In this case the best possible explanation for preservation of pre-excitation during complete heart block was the existence of accessory fibres of Mahaim.     

Congestive heart failure. New frontiers.

Congestive heart failure is a common syndrome with high mortality in its advanced stages. Current therapy includes the use of vasodilator drugs, which have been shown to prolong life. Despite current therapy, mortality remains high in patients with severe heart failure. Potent new inotropic vasodilators have improved ventricular performance but have not prolonged life in patients with end-stage heart failure. Serious arrhythmias are implicated in the sudden deaths of 30% to 40% of patients with severe heart failure, but the benefits of antiarrhythmic therapy have not been established. Upcoming trials will address this question. Ventricular remodeling and progressive dilatation after myocardial infarction commonly lead to congestive heart failure; early unloading of the ventricle with an angiotensin-converting enzyme inhibitor may attenuate these events. These findings support the concept that angiotensin-converting enzyme inhibitors may be useful in managing heart failure of all degrees of severity, including left ventricular dysfunction and end-stage heart failure. Part of the damage that may occur with acute myocardial infarction, particularly in this era of thrombolysis therapy, is reperfusion injury, which may be mediated by oxygen-derived free radicals. Better knowledge of the mechanisms and treatment of myocardial infarction, the leading cause of congestive heart failure, may help prevent or attenuate the development of this syndrome.     

Indications for Treatment of Complete Atrioventricular Dissociation

For purposes of correct treatment it is important to recognize that patients with complete atrioventricular dissociation fall into three groups: Group I—established third-degree heart block with and without Stokes-Adams attacks; Group II—periodic third-degree heart block with and without Stokes-Adams attacks; Group III—established third-degree heart block with cardiac failure. Most patients in Group I present no technical problems when a pacemaker is implanted. In Group II it is advisable to insert a temporary intracardiac catheter electrode and maintain a rate of 60 to 64 during the periods of third-degree heart block. Sudden reversion, in this group, from sinus rhythm can be fatal. Group III patients will often require a pacemaker set in excess of 74 beats until they are free of cardiac failure. Fifteen of 20 patients with complete atrioventricular dissociation showed marked functional improvement after insertion of a pacemaker. The development, in our laboratory, of a 4″ portable pacemaker impulse detector has been invaluable in locating the cause of failure in an implanted pacemaker.     

Survival in acute myocardial infarction; factors observed in 318 patients

Factors influencing survival in a group of 318 cases of acute myocardial infarction were analyzed. The mortality rate for the entire series was 41 per cent. Among the men it was 39.5 per cent; among women, 44.4 per cent. The mortality rate increased with the age of the patient. Twenty-six per cent of all deaths occurred within the first 24 hours, 44 per cent within 72 hours, and 71 per cent within the first week following hospital admission. Increased mortality rate was associated with previous history of congestive failure, myocardial infarction, hypertension or cardiomegaly. As to circumstances immediately preceding an infarction, the only ones that seemed to be related to a high mortality rate were hemorrhage and the postoperative state. Not only the presence but the degree of shock, congestive failure, cyanosis and dyspnea adversely influenced chances for survival. Duration, location, radiation and number of attacks of pain did not appear to be associated with extraordinary mortality rates. Anterior was slightly more common than posterior infarctions, and the mortality rate was much higher. Thromboembolic complications and certain disorders of rhythm and of conduction definitely worsen prognosis. Comparison of average mortality data as reported in different studies on acute myocardial infarction is improper and misleading because of the great differences between the kinds of patients included in various series reported upon. A standard method of grading the severity of acute myocardial infarction would help toward sounder comparisons.     

Emergency aorto-coronary venous bypass graft in cardiogenic shock

The mortality rate of shock complicating myocardial infarction is extremely high (80-100%) despite intensive medical management. Five patients with acute myocardial infarction and cardiogenic shock received an emergency aorto-coronary bypass graft, from three hours to five days after the onset of infarction and three to nine hours after the onset of shock. Selective coronary angiography was performed in all cases prior to operation. Four of the five patients survived and were discharged from hospital. Two cases with A-V dissociation and complete heart block reverted to normal sinus rhythm after the operation. This limited experience indicates that emergency aortocoronary bypass graft surgery can reduce mortality significantly in properly selected cases of cardiogenic shock.     

Artificial Cardiac Pacemakers

Nine patients with complete heart block and Stokes-Adams disease were treated with subcutaneously implanted, fixed-rate, artificial cardiac pacemakers. All of these patients were refractory to medical treatment and confined to bed by the frequency of their attacks. One patient died in uremia one month after operation; in the remaining eight, the implanted pacemakers are providing adequate stimulation at present. These patients are free of seizures and show an improvement in the amount of their physical activity. A fixed rate of 60 to 65 per minute was adequate in all cases. The results of our clinical experience with cardiac pacemakers is satisfactory, but the possibility of mechanical failure limits their use to situations in which the patient is incapacitated despite medical treatment.     

The Artificial Cardiac Pacemaker—Indications for Implantation

Extensive clinical experience has demonstrated that implantable cardiac pacemakers are safe and effective mechanisms for controlling symptoms and preventing the hazards of third degree heart block with Stokes-Adams syncope. Medical management of this disease does not provide reliable protection and life expectancy averages about two years after diagnosis. Hence the negligible surgical morbidity and mortality associated with pacemaker implantation justifies broad indications to implant one of the four commercially available battery-powered units.Elective implantation of a pacemaker should be considered in patients with persistent third degree heart block who have had: One or more episodes of Stokes-Adams syncope; surgical injury to the conduction system, regardless of syncopal attacks; evidence of low cardiac output with cardiomegaly secondary to bradycardia. Few if any other cardiac arrythmias are satisfactorily controlled by an electrical pacemaker.Emergency pacemaker control is obviously necessary for patients developing intractable or recurrent bouts of asystole. During the interval until an implantable unit can be obtained and sterilized, the patient may be controlled by intravenous isoproterenol or by an external pacemaker attached to a transvenous catheter electrode, a precordial skin electrode or a percutaneous myocardial wire electrode.     

Advanced Heart Block During Acute Myocardial Infarction Treated with an Electrode Pacing Catheter

The mortality rate is high from advanced atrioventricular block associated with acute myocardial infarction. There is reason to believe that if in these patients the hearts are electrically paced with an endocardial pacing catheter, the mortality rate can be considerably decreased. Five patients in second- and third-degree heart block associated with acute myocardial infarction were paced with a considerable lowering of the expected mortality rate. Twenty-three cases from the literature are also presented and discussed. A silastic bipolar electrode catheter was used in these five cases. Four of the five cases returned to normal sinus rhythm within the first 10 days. The average duration of pacing was 6.7 days. It is the opinion of the author that second- and third-degree heart block associated with acute myocardial infarction should have a pacing catheter introduced at the earliest possible moment for continuous or demand endocardial pacing.     

急性心肌梗死患者肠道优势菌群分析

目的探讨急性心肌梗死患者肠道优势菌群的改变及其与疾病严重程度的关系。方法共筛选急性心肌梗死患者71名及正常健康体检者33名,急性心肌梗死患者根据是否心衰分为急性心肌梗死组36名和急性心肌梗死伴泵衰竭组35名,所有入选者收集大便及血清标本,分别采用qPCR及化学发光仪测定肠道优势菌群改变和血清脑钠肽前体及肌钙蛋白水平。结果急性心肌梗死患者肠道优势菌群显著改变,肠道肠杆菌以及肠球菌细菌数量较对照组显著增加,均与脑钠肽前体、肌钙蛋白、Killip分级显著正相关,而双歧杆菌、乳酸杆菌等细菌数量显著降低,与脑钠肽前体、肌钙蛋白、Killip分级显著负相关。结论急性心肌梗死患者呈现典型的肠道菌群紊乱,且与患者疾病严重程度相关。     

Metabolic syndrome X--high risk factor for acute myocardial infarction and its complications

Metabolic Syndrome X is a clinical entity which comprises the following factors: diabetes mellitus, arterial hypertension, high levels of triglyceride and/or low levels of HDL cholesterol, central obesity and microalbuminuria (by WHO criteria). The first goal of this study was to determine the frequency of the Metabolic Syndrome X (MSX) in patients with acute myocardial infarction compared with the general population. The second goal of the study was to examine the frequency of heart failure and reinfarction rate in the patients with myocardial infarction, with and without MSX. Furthermore, the relationship between gender and MSX was analyzed. A total of 101 patients with acute myocardial infarction took part in randomized trial (32 women and 69 men). MSX and all of its components were diagnosed according to WHO criteria. To determine statistical significance of our results, we used chi2 test and t-test for independent samples. From 101 patient 48 had MSX (47.52%), while in the general population incidence of MSX is 3-4%. The reinfarction and the heart failure rate were significantly higher in the group of patients with MSX (p = 0.0067 and p = 0.0217, respectively). To conclude, the results of the present study confirm that MSX is a high risk factor for myocardial infarction and its complications.     

Mechanical Complications of Myocardial Infarction—Radiologic Aspects

Left ventricular aneurysm, interventricular septal defect and acute mitral valve incompetence due to papillary muscle damage are three mechanical complications which cause intractable heart failure following myocardial infarction. In each case surgical intervention can result in dramatic improvement of congestive heart failure.A hemodynamically significant left ventricular aneurysm enlarges the cardiac silhouette and frequently causes a localized protrusion as seen radiographically. Cardiac fluoroscopy will disclose an abnormal pulsation of the left ventricular border. The left ventricular angiogram establishes the diagnosis, reveals the extent of the aneurysm and may disclose a filling defect in the aneurysmal sac due to the presence of mural thrombus. Coronary arteriography shows occlusion of a major vessel, most commonly the anterior descending branch of the left coronary artery.Ischemic perforation of the interventricular septum and acute mitral incompetence due to severe papillary muscle damage both cause severe heart failure shortly after myocardial infarction. A similar pansystolic murmur accompanies both conditions, and differentiation between the two is rarely possible on the basis of the electrocardiogram or x-ray film of the chest. Ventricular cardiac catheterization and left ventricular angiocardiography are required for a correct diagnosis.     

Antioxidant vitamin levels do not exhibit negative correlation with the extent of acute myocardial infarction

Serum levels of vitamin E (VE), beta-carotene (BC) and vitamin C (VC) were determined in 50 patients with the first acute myocardial infarction (AMI) before starting thrombolytical treatment. VE and BC were determined by HPLC, VC spectrophotometrically. The reperfused patients were divided according to vitamin concentrations into four groups. The lowest quartile was compared with the rest of the studied population (VE: group with high (H)>15.6 microM>group with low (L), BC: H>0.07 microM>L, VC: H>25 microM>L) in the following parameters: extent of myocardial damage (area under the curves of troponin I, CK-MB during 48 h), arrhythmia and congestive heart failure occurrence, size of ejection fraction, positivity of ventricular late potentials. No significant differences between groups H and L for either VE, BC or VC were found (P 0.05). As no correlation between serum concentrations of vitamins E, C and beta-carotene and the extent and clinical course of AMI was found, the actual vitamin concentrations may be important for prevention of ischemic heart a disease, but they do not play a decisive role in the acute phase of myocardial infarction in humans.     

Clinical observations and echocardiographic features of mural thrombi in the left ventricle during myocardial infarction]

The incidence and changes in the mural thrombi in left ventricle in ECHO-2D in the acute myocardial infarction as well as relationship between clinical parameters and echocardiographic indices of the left cardiac ventricle contractability asynergy and dynamics of changes in mural thrombi have been investigated. The studies included 137 consecutive patients (98 males and 39 females) treated for the acute myocardial infarction. Patients' age ranged from 35 to 87 years (mean 62 years). Infarction of the anterior and/or lateral wall was diagnosed in 67 patients, and infarction of the inferior and/or posterior wall in 70 patients. Mural thrombi were diagnosed in 42 (31%) patients. Eighteen thrombi (43%) were liquefied during hospitalization. Comparative analysis of patients in whom mural thrombi underwent liquefaction in the hospital and a group of patients with myocardial infarction and persisting mural thrombi showed that return of left ventricle movements with subsequent contractability facilitate liquefaction of mural thrombi. Higher mortality rate in the group of patients with myocardial infarction with mural thrombi is due to extension of the infarction accompanied by marked asynergy of left ventricular contractions which does not decrease in sequential examinations, and increasing congestive heart failure.     

血清Trx1、FGL2与急性心肌梗死后心力衰竭患者预后的关系

摘要 目的：探讨血清硫氧还蛋白1（Trx1）、纤维蛋白原样蛋白2（FGL2）与急性心肌梗死后心力衰竭患者预后的关系。方法：选择2019年10月至2020年5月我院收治的158例急性心肌梗死后心力衰竭患者作为观察组,并根据心功能Killip分级分为Ⅱ级组54例、Ⅲ级组57例、Ⅳ级组47例。另选择同期我院收治的102例急性心肌梗死患者作为对照组。入院后采用酶联免疫吸附法（ELISA）检测所有患者血清Trx1、FGL2水平;观察组患者出院后随访2年,并根据是否出现主要不良心血管事件（MACE）将患者分为预后不良组和预后良好组。采用多因素Logistic回归分析影响急性心肌梗死后心力衰竭患者预后的相关因素,采用受试者工作特征（ROC）曲线评估血清Trx1、FGL2对急性心肌梗死后心力衰竭患者预后的预测价值。结果：观察组血清FGL2水平明显高于对照组,血清Trx1水平明显低于对照组（P<0.05）;心功能Killip分级Ⅳ级组患者血清Trx1水平明显低于Ⅱ级组、Ⅲ级组（P<0.05）,血清FGL2水平明显高于Ⅱ级组、Ⅲ级组（P<0.05）。预后不良组患者血清Trx1、LVEF均明显低于预后良好组,而年龄、血清FGL2及血尿酸、血肌酐、N末端B型利钠肽原（NT-proBNP）均明显高于预后良好组（P<0.05）,两组心功能Killip分级比例比较差异有统计学意义（P<0.05）。多因素Logistic回归分析显示,年龄（较高）、心功能Killip分级为Ⅳ级、Trx1下降、FGL2升高均是影响急性心肌梗死后心力衰竭患者预后的危险因素（P<0.05）。ROC曲线结果显示,血清Trx1、FGL2预测急性心肌梗死后心力衰竭患者预后的曲线下面积分别为0.807、0.811,两者联合检测预测急性心肌梗死后心力衰竭患者预后的曲线下面积为0.889。结论：急性心肌梗死后心力衰竭患者血清中Trx1水平降低,FGL2水平升高,且血清Trx1、FGL2水平与患者心功能分级及预后密切相关,可作为评估急性心肌梗死后心力衰竭患者预后的辅助性指标。     

Predictive values of sST2 and IL-33 for heart failure in patients with acute myocardial infarction

Timely prediction of the risk of heart failure in acute myocardial infarction patients is critical for better prognosis. This article aims to evaluate the predictive value of serum soluble growth stimulation expressed gene 2 (sST2) and interleukin-33 in patients with acute myocardial infarction complicated by heart failure. A total of 42 healthy controls and 144 acute myocardial infarction patients were recruited in the study. According to Killip cardiac function classification as the basis for concurrent heart failure, they were distributed into non-heart failure group (n = 76) and heart failure group (n = 68). ELISA was utilized to determine the serum sST2 and interleukin-33 levels, and the diagnostic efficiency was evaluated by receiver operating characteristics curve. sST2 and interleukin-33 levels in patients with acute myocardial infarction were significantly increased when compared with normal healthy controls, and were further enhanced in the heart failure group. With the increased Killip cardiac function classification, interleukin-33 and sST2 levels were gradually elevated. Multivariate analysis indicated that interleukin-33 and sST2 could be used as independent predictors for heart failure combined with acute myocardial infarction.     

Cardiac predictors of death after non-cardiac surgery evaluated by intention to treat.

Cardiac risk factors were studied among patients who were admitted to hospital with appendicitis or a fracture of the proximal femur less than one year after being admitted with myocardial infarction. Of 99 patients with myocardial infarction and appendicitis, 87 underwent appendicectomy; and of 221 with myocardial infarction and hip fracture, 179 were operated on. The patients were studied on an intention to treat basis. The mortality within one month was 9% and 16% respectively. A history of congestive heart failure was the dominating risk factor, while ischaemic heart disease (recent myocardial infarction or angina pectoris) had no independent association with mortality. If the ventricular function is known additional preoperative information about the heart is of negligible value when estimating the mortality of non-cardiac surgery.     

Cardiac Monitoring in a Community Hospital—Analysis of 18 Months' Experience

Cardiac monitoring facilities have been present in teaching hospital centers for over five years. A substantial decrease in mortality has been observed in monitored patients with acute myocardial infarction. The community hospital system offers a challenge to effective monitoring since many physicians care for patients and often many kinds of therapy are used.After 18 months of operation mortality from myocardial infarction was only 16.6 percent in a community hospital monitoring unit where the majority of the emergency care and resuscitation was carried out by nurses. Vital to this success was the use of standing orders for nurses, requirement of privilege to practice within the monitoring facility and acceptance of the nurse as a therapist in emergency situations.Fourteen patients were successfully resuscitated and were later discharged from the hospital. Four of them had ventricular fibrillation from digitalis intoxication.Patients with shock and severe congestive heart failure continue to be a major unsolved clinical problem. The results indicate that the potentially viable patient with serious electrical disturbances can almost invariably be salvaged.     

老年急性心肌梗死并心源性休克冠状动脉介入治疗的临床效果分析

目的:对比分析介入治疗和保守治疗对急性心梗合并心源性休克的老年患者的治疗效果。方法:回顾性分析急性心肌梗死并心源性休克患者,共入选230例,按照医生评估进行分组治疗,分为介入治疗组和非介入治疗组,介入组患者120例,接受冠脉介入治疗;非介入组患者110例,接受非介入治疗。对比分析危险因素以及治疗效果。结果:介入组中心肌梗死病史及心衰病史患者明显高于非介入组(24.2%vs 20%P<0.05;25%vs 17.3%,P<0.05),经皮冠状动脉介入治疗与非介入治疗相比能显著降低急性心梗合并心源性休克的老年患者住院病死率(40.8%vs 71.8%,P<0.05),非介入治疗组心律失常发生率高于介入治疗组(26.7%vs 21.8%,P<0.05),同时非介入治疗组肺部感染及肾衰的发病率较高(11.8%vs 5.8%P<0.05;8.2%vs 2.0%,P<0.05)。结论:针对急性心梗合并心源性休克的老年患者制定治疗方案时,虽然介入治疗存在更多的并发症,但是可以显著改善患者预后。