Acute coronary syndrome and heart failure

Acute coronary syndrome describes a range of clinical conditions that arise from acute myocardial ischaemia and includes unstable angina, non-ST-segment elevation myocardial infarction (NSTEMI) and ST-segment elevation myocardial infarction (STEMI). It presents with chest pain, pressure, tightness, or heaviness that radiates to neck, jaw, shoulders, back, or one or both arms. Heart failure occurring in the environment of an acute coronary syndrome describes an inability of the heart to sustain adequate forward blood flow for metabolizing tissues. It may be a direct consequence of myocardial ischaemia or infarction with abnormal systolic function, or be secondary to acute valvular regurgitation or ventricular septal rupture. In its most severe form acute heart failure is termed cardiogenic shock. The priority of treatment in both conditions is to use ECG and biochemical cardiac markers to identify patients with STEMI who may benefit from immediate reperfusion therapy. In patients with STEMI, blood flow to the myocardium may be restored with thrombolytic therapy or percutaneous coronary intervention. Patients with unstable angina or NSTEMI require therapy to prevent progression to full-thickness myocardial infarction, with anti-platelet and anticoagulant medication and β-blockade. Patients who develop heart failure following myocardial ischaemia or infarction may be risk-stratified by measuring B-type natriuretic peptide. Once cardiogenic shock has developed the prognosis is poor, with an estimated mortality rate of 75%. Patients may require invasive monitoring, ventilatory support, cardiovascular support, or intra-aortic balloon counterpulsation.     

Thoracic epidural anesthesia and central hemodynamics in patients with unstable angina pectoris

The effects of high thoracic epidural anesthesia (TEA) on central hemodynamics as measured by pulmonary arterial catheterization were studied in nine patients with severe coronary artery disease and unstable angina pectoris. The patients were also treated with a combination of beta-blockers, calcium antagonists, and nitrates, as well as salicylates, low-dose heparin, and nitroglycerin infusion for greater than 24 hr. Management of pain with high TEA was started with the bolus epidural injection of 4.3 +/- 0.2 mL bupivacaine (5 mg/mL), which induced a sympathetic blockade from Th. During ischemic chest pain, pulmonary artery and pulmonary capillary wedge pressures were significantly increased. TEA, while relieving the chest pain, significantly decreased systolic arterial blood pressure, heart rate, and pulmonary artery and pulmonary capillary wedge pressures, without any significant changes in coronary perfusion pressure, cardiac output, stroke volume, and systemic or pulmonary vascular resistances. In some patients, ST-segment depression was less pronounced during TEA. Thus, during ischemic chest pain, TEA has beneficial effects on the major determinants of myocardial oxygen consumption, without jeopardizing coronary perfusion pressure. TEA may therefore favorably alter the oxygen supply/demand ratio within ischemic myocardial areas.     

Surgical management of acute myocardial ischemia following percutaneous transluminal coronary angioplasty. Role of the intra-aortic balloon pump

Acute myocardial ischemia is a serious complication of percutaneous transluminal coronary angioplasty, often requiring emergency myocardial revascularization. Since our initial report of 17 such patients, we have encountered an additional 32 patients requiring emergency myocardial revascularization since September, 1981. The indication for emergency myocardial revascularization was ischemic chest pain in all 32 patients. Percutaneous transluminal coronary angioplasty resulted in injury to the right coronary artery in 11 patients, the left anterior descending artery in 19 patients, and the left main artery in two patients. The onset of ischemia was immediate in 26 patients but delayed up to 22 hours in six patients. Chest pain was associated with ST-segment elevation in 21 patients, hypotension in 7 patients, and cardiac arrest in 6 patients. Immediate intra-aortic balloon pumping was instituted in the angioplasty suite in 16 patients. The mean time from onset of ischemia to completed revascularization was 156 minutes with a mean of 1.6 grafts performed per patient. Seventeen patients (53%) had enzyme evidence of myocardial infarction postoperatively, with a significantly higher (p less than 0.01) incidence of myocardial infarction in those patients with preoperative ST elevation (76% versus 9%). In the 21 patients with ST-segment elevation, the incidence of Q wave infarction was 20% (3/15) with balloon pumping and 50% (3/6) without balloon pumping. Complications associated with intra-aortic balloon pumping occurred in one patient (6%). There were no hospital or late deaths with follow-up extending 16 months. The spectrum of injury resulting from percutaneous transluminal coronary angioplasty extends from chest pain alone to severe transmural ischemia with hypotension or cardiac arrest. Presentation may be immediate or delayed. Urgent emergency myocardial revascularization remains the accepted therapy for this complication. Immediate preoperative intra-aortic balloon pumping is a useful adjunct to emergency myocardial revascularization in the group of patients with acute ischemia and ST-segment elevation.     

急性ST段抬高型心肌梗死患者诊疗流程优化研究

目的探讨优化胸痛诊疗流程对急性ST段抬高型心肌梗死患者入门至球囊扩张时间(D-to-B时间)的影响。方法将130例急诊行经皮冠状动脉介入的急性ST段抬高型心肌梗死患者按就诊时间分组,2015年3~12月就诊的58例患者设为对照组,2016年1~8月就诊的72例患者设为优化组,对照组按常规胸痛诊疗流程处理,优化组按优化的胸痛诊疗流程处理。比较两组D-to-B时间及达标率。结果优化组D-to-B时间为(81.44±39.31)min,D-to-B时间达标率为69.44%;对照组分别为(162.50±81.27)min、20.69%。两组比较,差异有统计学意义(均P0.01)。结论将优化的胸痛诊疗流程用于管理急性ST段抬高型心肌梗死患者,可有效缩短D-to-B时间,减少心肌缺血时间,挽救患者生命。     

Aspects of the value of continuous ambulatory ECG monitoring in the detection and management of ischaemic heart disease. Case reports

In 2 patients admitted for evaluation of chest pain occurring mainly at rest, organic disease of the nondominant circumflex artery only, with normal left anterior descending and right coronary arteries, was demonstrated in each case. Continuous ambulatory ECG monitoring by the Holter system revealed episodes of ST-segment elevation probably due to coronary artery spasm, allowing specific treatment to be instituted. Some aspects of the value of continuous ambulatory Holter monitoring in patients with ischaemic heart disease are discussed.     

Pulmonary embolism mimicking anteroseptal acute myocardial infarction

Pulmonary embolism (PE) is a potentially lethal condition that presents in patients with chest pain or shortness of breath. Although electrocardiograms (ECGs) typically demonstrate abnormalities associated with PE, ST-segment elevation, which can indicate anteroseptal acute myocardial infarction (AMI), has-on rare occasions-been noted on ECGs of patients with acute PE. The current report documents the case of a 57-year-old man who presented to the emergency department with chest pain. Findings from an ECG suggested anteroseptal AMI; however, cardiac catheterization indicated that the patient did not have critical ischemic heart disease. On further examination, the patient was found to have a massive bilateral PE. The present report emphasizes that physicians must investigate PE in all patients presenting with chest pain, dyspnea, or both, even in the face of ECG changes that are suggestive of a cardiac etiology. A brief discussion of the current theories of ST-segment elevation in the setting of PE is also included.     

Acute cholecystits leading to ischemic ECG changes in a patient with no underlying cardiac disease

Although chest pain with ST-segment elevation is often indicative of cardiac ischemia, it has also been described with surgical conditions such as acute cholecystitis. We report the case of a 34-year-old Caucasian female who was referred with symptoms consistent with acute cholecystitis. An electrocardiogram (ECG) showed unexpected changes with inferolateral ST-segment elevation indicative of an inferolateral myocardial infarct. Further investigations and analysis of the results along with the clinical picture meant an acute cardiac event was excluded. Gallstones were seen on ultrasound and an inflamed gallbladder, consistent with acute cholecystitis, was confirmed at laparoscopic cholecystectomy. This led to the resolution of her symptoms and a return to the isoelectric baseline of the ST segments on the ECG. Five previous cases of cholecystitis induced ECG changes have been described in the literature. This case describes the youngest patient with no previous cardiac disease. We review the literature and suggest the pathophysiological mechanism to explain these findings. When the initial diagnostic interventions for chest pain with ST-segment elevation do not yield the expected results, an alternative diagnosis such as cholecystitis should be considered.     

Exercise-induced ST-segment elevation possibly caused by coronary artery spasm. A case presentation and review

A 36-year-old man with classic angina pectoris had marked ST-segment elevation (STE) in the inferior leads on stress-testing in the absence of chest pain. There was no evidence of previous myocardial infarction (MI). Selective coronary arteriography delineated severe obstructions in the right coronary artery (RCA) with additional left circumflex coronary artery (LCx) obstruction. Left ventricular cine-angiography established that there was normal contractility and confirmed the absence of past MI. Coronary artery bypass graft surgery to the RCA and LCx was unfortunately complicated by an acute transmural inferoposterolateral MI. Treadmill stress testing 6 weeks after surgery failed to demonstrate the preoperative ST-segment change. The patient may have developed exercise-induced coronary artery spasm superimposed on the severe proximal RCA stenosis; this in turn may have caused the inferior STE. Exercise-induced STE is reviewed.     

Early diagnosis and exclusion of acute myocardial infarction by two hours' vector-ECG and determination of either myoglobin or CK-mb. BIOMACS-study. BIOchemical Markers in Acute Coronary Syndromes

This retrospective study assesses the early diagnostic potential of a combination of multilead continuous vectorcardiography (VCG) and biochemical markers (myoglobin, troponin-t and CK-mb mass) in patients with chest pain who present with suspected acute myocardial infarction (AMI), but without ST-elevation on resting 12-lead ECG on admission. Within a multicenter study 56 patients admitted for chest pain (< 12 h) and with a non-diagnostic 12-lead ECG on admission and a VCG recording were included. Venous blood samples were drawn on admission and the continuous VCG was monitored for 2 h. The results were related to the clinical diagnosis of AMI. Neither the biochemical markers nor VCG alone permitted the diagnosis or exclusion of AMI at admission. However, if either analysis of myoglobin on admission or 2 h of VCG recording were positive, they would have a sensitivity for detection of AMI of 100% and specificity of 69%. In a subset of patients with more than 4 h delay since start of chest pain, CK-mb could replace myoglobin and give a sensitivity of 100% and a specificity of 81%. Determination of myoglobin or CK-mb at admission and VCG monitoring for 2 h can reliably confirm or exclude AMI within 2 h. This combination seems useful for early stratifications of patients in chest pain or coronary care units.     

Early Diagnosis and Exclusion of Acute Myocardial Infarction by Two Hours' Vector-ECG and Determination of Either Myoglobin or CK-mb

This retrospective study assesses the early diagnostic potential of a combination of multilead continuous vectorcardiography (VCG) and biochemical markers (myoglobin, troponin-t and CK-mb mass) in patients with chest pain who present with suspected acute myocardial infarction (AMI), but without ST-elevation on resting 12-lead ECG on admission. Within a multicenter study 56 patients admitted for chest pain (&lt;12 h) and with a non-diagnostic 12-lead ECG on admission and a VCG recording were included. Venous blood samples were drawn on admission and the continuous VCG was monitored for 2 h. The results were related to the clinical diagnosis of AMI. Neither the biochemical markers nor VCG alone permitted the diagnosis or exclusion of AMI at admission. However, if either analysis of myoglobin on admission or 2 h of VCG recording were positive, they would have a sensitivity for detection of AMI of 100% and specificity of 69%. In a subset of patients with more than 4 h delay since start of chest pain, CK-mb could replace myoglobin and give a sensitivity of 100% and a specificity of 81%. Determination of myoglobin or CK-mb at admission and VCG monitoring for 2 h can reliably confirm or exclude AMI within 2 h. This combination seems useful for early stratifications of patients in chest pain or coronary care units.     

OPCAB for acute LAD dissection due to blunt chest trauma

A 40-year-old male pedestrian was hit by a truck and was admitted with multiple injuries including blunt chest trauma. Electrocardiogram revealed acute anterior ST-segment elevation and myocardial infarction. Coronary angiography demonstrated acute ostial left anterior descending coronary artery dissection. Due to extent and location, the lesion was not amenable for angioplasty. Multiple associated injuries and severely impaired coagulation studies directed us to perform emergency off-pump coronary artery bypass grafting.     

Myocardial ischaemia in normal patients undergoing elective Caesarean section: a peripartum assessment

Incidence rates of electrocardiographic changes during Caesarean section vary from 25 to 60%. To date, no investigator has identified myocardial ischaemia resulting from these changes. We investigated patients undergoing elective Caesarean section using peripartum Holter monitoring and serum analysis of cardiac troponin I (cTnI). Twenty-six patients presenting for elective Caesarean section were studied. Peroperative Holter monitoring continued for 12 h postoperatively, at which time blood samples for cTnI levels were taken. Significant ST changes were recorded in 42% of patients peroperatively and 38.5% of patients postoperatively. Forty-two per cent of patients experienced peroperative chest pain requiring opioid analgesia. Chest pain was significantly associated with abnormal electrocardiogram (ECG) findings. Ischaemic levels of cTnI were recorded in two patients. This study reports, for the first time, myocardial ischaemia (7.69% of patients) arising in conjunction with the ECG changes seen during elective Caesarean section. We also report episodes of significant postoperative ST-segment changes.     

Acute coronary syndromes: the reperfusion era and beyond

The recent decade has enjoyed and provided major advances in our understanding of the pathophysiology and treatment of patients with acute coronary syndromes. The use of reperfusion therapy and acute mechanical intervention in patients with acute myocardial infarction has dramatically advanced our understanding of the mechanisms of acute coronary events. The disrupted unstable plaque is the proximate cause of acute coronary syndrome in the majority of patients, most experiencing the plaque rupture of a lipid-laden lesion. This results in a spectrum of clinical disease with clinical presentations ranging from unstable angina to ST-elevation myocardial infarction. Although a common aetiology exists, treatment is not uniform. The triage of patients and risk stratification are paramount to selecting the appropriate therapy at the right time for individual patients.     

Acute myocardial infarction due to coronary artery spasm after caesarean section

We experienced acute myocardial infarction due to coronary artery spasm after caesarean section. A 41-year-old multigravida woman with no previous cardiac history or coronary risk factor developed acute myocardial infarction after caesarean section, and was successfully resuscitated with emergency percutaneous transluminal coronary angioplasty. Acute myocardial infarction during pregnancy and postpartum period is a rare event, but could be associated with high mortality if it occurs. It is necessary to consider the possibility of acute myocardial infarction and provide early diagnosis and treatment by multidisciplinary team when a pregnant woman complains of retrosternal chest pain.     

Coronary artery stenting as a bridge to surgery in a patient with Stanford type A acute aortic dissection involving left main trunk of coronary artery

An 80-year-old woman was transferred to our hospital with sudden onset of chest pain. Electorocardiogram (ECG) showed ST-segment elevation of VI-V3 and aV(L) leads suggestive of acute coronary syndrome. On emergent coronary angiography, left main trunk (LMT) was externally compressed only at diastolic phase, showing acute type A aortic dissection involving the left coronary artery. A bare metal stent was promptly implanted to LMT to restore coronary blood flow because of her hemodynamic instability. Soon after this procedure, ischemic changes disappeared on ECG and she was transferred to the operating room in stable hemodynamic condition without chest discomfort. Emergent graft replacement of ascending aorta and proximal portion of transverse arch was successfully performed. As the bare metal stent had been properly implanted at the LMT and weaning from cardiopulmonary bypass was uneventful regardless of decreased left ventricular wall motion of anteroseptal area, coronary artery bypass grafting was not performed. A "bridge to surgery" use of coronary stenting was very effective as a life saving procedure for the patients with acute aortic dissection involving the left coronary artery.     

Myokardinfarkt – ein algorithmusbasierter Leitfaden für die Praxis

The different clinical manifestations of acute coronary syndrome represent the most frequent catchwords for emergency services missions. The guiding clinical symptom is persistent (>20 min) thoracic pain. Additional clinical symptoms such as “dyspnoea”, “vertigo” or “vegetative disorders” are frequent. Certain pathological findings in the course of clinical examination indicate that complications of acute coronary syndrome have already occurred. The electrocardiogram represents the central technical medium for diagnostics, therapy and follow-up monitoring of acute coronary syndrome. The positive proof of ST elevation as well as a (newly developed) left bundle branch block in conjunction with the above-mentioned clinical signs already serve by definition as sole criteria to differentiate ST elevation myocardial infarction (STEMI) from unstable angina pectoris as well as from non-ST elevation myocardial infarction (NSTEMI). Employment of a strict diagnostic algorithm may not prevent but should considerably minimize the potential standard error of the medical or non-medical examiner to overlook or wrongly interpret relevant findings when diagnosing an acute illness or injury.     

Acute Coronary Syndromes after Renal Transplantation in Patients with End-Stage Renal Disease Resulting from Diabetes

Coronary heart disease is the leading cause of death in both diabetes mellitus and end-stage renal disease. Although renal transplantation is known to reduce mortality in end-stage renal disease, its effect on the incidence of acute coronary syndromes is unknown. Using data from the United States Renal Data System, we studied 11,369 patients with end-stage renal disease due to diabetes enrolled on the renal and renal-pancreas transplant waiting list from 1 July 1994 to 30 June 1997. Cox nonproportional hazards regression models were used to calculate the adjusted, time-dependent relative risk for the most recent hospitalization for acute coronary syndromes (including acute myocardial infarction, unstable angina, or other acute coronary syndromes, ICD9 Code 410.x or 411.x) for a given patient in the study period. Demographics and comorbidities were controlled by using data from the medical evidence form (HCFA 2728). After renal transplantation, patients had an incidence of acute coronary syndromes of 0.79% per patient year, compared to 1.67% per patient year prior to transplantation. In comparison to maintenance dialysis, renal transplantation was independently associated with a lower risk for acute coronary syndromes (hazard ratio 0.38, 95% confidence interval, 0.30-0.49). Patients with end-stage renal disease due to diabetes on the renal transplant waiting list were much less likely to be hospitalized for acute coronary syndromes after renal transplantation. The reasons for this decreased risk should be the subject of further study.     

Diagnostische Abklärung des akuten Koronarsyndroms bei älteren Patienten in der Notaufnahme

Diagnostic algorithm in the emergency department

Elderly patients admitted to hospital with acute chest pain must be investigated in a timely and structured manner. The evaluation of an acute coronary syndrome includes a physical examination, recording of a 12-lead electrocardiogram (ECG), measurement of cardiac biomarkers, usually of troponin T or I and an echocardiographic examination in addition to the past medical history. The evaluation is frequently followed by an observation period with monitoring of ECG and troponin and possibly by a stress test.

Diagnosis

With consideration of all findings the diagnosis of an acute myocardial infarction can be made. The diagnosis among elderly patients is frequently difficult as they often exhibit atypical complaints. Patients who are at high or intermediate risk for future cardiovascular events should undergo an invasive evaluation. Low-risk patients have a favorable prognosis and can be treated as outpatients. This article provides an overview on the diagnosis of acute coronary syndrome in elderly patients.     

Coronary artery bypass without cardioplegia

Cardioplegic myocardial protection has become the standard for coronary artery bypass. In contrast, we report 500 consecutive coronary artery bypass operations with intermittent aortic clamping for distal anastomoses, left ventricular venting, and 30 degrees C hypothermia. Average patient age was 62 years (range of 30 to 89 years). The number of patients who had urgent or emergency operations was 194 (39%); 251 patients had unstable angina, and 123 others had preinfarction angina (pain at rest in the hospital); 27 had evolving myocardial infarction. The average number of grafts was 3.3 per patient, and the average ischemic time was 7.65 minutes per graft. There were five hospital deaths (1%); none resulted from poor myocardial protection that caused low cardiac output. Only three survivors (0.6%) required a balloon pump to be weaned from cardiopulmonary bypass: two had acute infarctions preoperatively, and the other had an ejection fraction of 0.30 and intractable atrial arrhythmias. Only two other patients (0.4%) received any inotropic infusions postoperatively. Eighteen patients (3.6%) had a perioperative infarction. These results, particularly the virtual absence of postoperative inotropic support, in unselected patients of whom 80% had acute coronary syndromes, indicate that intermittent ischemia can provide excellent myocardial protection for coronary bypass. Brief periods of intermittent ischemia alleviate concern about cardioplegic protection via occluded coronaries or internal mammary grafts and provide a simple and safe option for myocardial protection during coronary artery bypass.     

Perioperative myocardial ischemia and infarction. Detection of myocardial ischemia using continuous electrocardiography.

Continuous ECG recording of ST segments can provide important insight into the effects of CAD in patients before, during, and after anesthesia and surgery. The stresses of anesthesia and surgery are particularly threatening to the patient with critical coronary disease and ischemia. ST-segment monitoring is a useful alternative to preoperative stress ECG in patients who are unable to exercise, particularly if radionuclide techniques are not readily available. Continuous ST-segment monitoring provides an additional and unique method of monitoring patients during and after surgery, and on-line analysis of such data provides the anesthesiologist with opportunities to recognize and promptly respond to ischemic episodes. Future studies will determine whether such aggressive strategies will alter the outcome for patients with perioperative myocardial ischemia.