Cardioprotection

The demographic change is associated with an increasing number of elderly patients with serious comorbidities. The prevalence of coronary heart disease in particular increases with age and raises the risk of perioperative myocardial ischemia. In the last few years various interventions have been evaluated to lower the perioperative risk for serious cardiovascular events. This includes cardioprotective medical interventions, for example with β-receptor blockers and statins. Current guidelines recommend that patients who are on β-receptor blockers or statins for chronic treatment of cardiovascular diseases should continue this medication throughout the perioperative period. Myocardial conditioning has been assessed to be effective under numerous experimental conditions and clinical trials have also provided evidence for myocardial protection by conditioning. Besides ischemic and anesthetic-induced preconditioning the noninvasive technique of remote preconditioning offers interesting possibilities, especially for patients with serious comorbidities; however, large scale randomized clinical multicentre trials are still needed. Regarding cardioprotective effectiveness, the clinical data for regional anesthesia are very heterogeneous; nevertheless regional anesthesia is very effective in postoperative pain therapy. Therefore regional anesthesia should be used as a part of multimodal therapy concepts to lower the risk of perioperative cardiovascular events.     

Aktuelle Evidenz einer Statintherapie in der Herzchirurgie

Statins have gained a pivotal role in the primary and secondary prevention of coronary artery disease. Postoperative statin therapy effectively reduce the rate of bypass graft failure and cardiovascular complications in patients who undergo coronary artery bypass grafting. However, the benefits of a perioperative statin therapy for cardiac surgery patients are currently under extensive investigation. Accumulating evidence from clinical trials suggests that patients scheduled for coronary artery bypass surgery profit from perioperative statin therapy and that discontinuation of statins during the perioperative period may increase adverse events. Whether an additional high-dose statin treatment shortly before myocardial revascularization reduces major adverse cardiocerebral events is currently being determined in a large clinical trial. In contrast to patients undergoing coronary artery bypass grafting, current evidence from clinical trials does not support the routine use of statins for the prevention of biological valve degeneration in patients having undergone valve replacement.     

Χ�������Ĺ����ϰ�����ԭ��ʹ���

??Cardiac dysfunction during perioperative period??Common causes and treatment YAN Jing??LI Li. Intensive Care Unit??Zhejiang Hospital??Hangzhou 310013??China
Corresponding author??YAN Jing??E-mail??zjicu@vip.163.com
Abstract Cardiac dysfunction is one of the most common complications of surgical patients during perioperative period??which lead to higher mortality rate??longer duration of hospitalization and more medical expenses. Thus??it is very important for early identification of high-risk patients??early intervention and early treatment. However??the risk factors of cardiac dysfunction during perioperative period is very complex??such as inappropriate fluid therapy??arrhythmia??hypertension??cardiovascular events??anesthesia??operation stress??etc. The treatment of cardiac dysfunction during perioperative period should follow the comments of multidisciplinary staff from surgery??cardiology and critically care??which should include the cardiovascular risk assessment. In addition??the patient's fluid and anti-arrhythmic therapy??cardiovascular event handling??operation??anesthesia and haemostatic scheme should be provided individually. Thus??the treatment can be optimized and improve security, reduce complications and improve the prognosis of patients.     

Evidence-based statin prescription for cardiovascular protection in renal impairment

Dyslipidemia is a well-known risk factor for cardiovascular disease in the general population, and the cardioprotective role of statins is well established. However, although cardiovascular disease is the major cause of morbidity and mortality in chronic kidney disease (CKD), the role of statin therapy is still under investigation. In CKD the atherosclerotic burden is high and pathophysiology of dyslipidemia is complex; however, the majority of large-scale statin trials excluded patients with CKD. Statins could have different effects in the different stages of CKD. Two large trials involving haemodialysis patients showed unfavourable results, whereas in renal transplant subjects as well as in early CKD subjects, statins reduced cardiovascular risk. The studies involving early CKD patients are post-hoc analyses of large trials and they showed that statins are more effective in secondary than in primary prevention. The aim of this study was to evaluate the effectiveness of statins for prevention of cardiovascular events by calculating the number of patients needed to be treated in different interventional trials. We conclude that dyslipidemia is a modifiable cardiovascular risk and statins appear to be an effective treatment especially in the early stages of CKD. Patients on renal replacement therapy could obtain an advantage from this treatment; however, the patient’s clinical prognosis should be taken into account when evaluating treatment.     

Regional versus general anesthesia in high-risk surgical patients: the need for a clinical trial

Regional anesthesia is often preferred over general anesthesia for patients with cardiovascular disease because of presumed decreased risk of perioperative myocardial ischemia. However, few studies have addressed this issue directly. To determine whether the type of anesthesia is independently associated with myocardial ischemia, records of 134 patients undergoing peripheral vascular grafting under general or regional anesthesia were examined. There were no significant differences preoperatively between groups in ASA class, age, sex, or prevalence of angina, diabetes, or hypertension. Twelve patients developed myocardial ischemia or infarction within 7 days of operation; 11 of these 12 patients had received regional anesthesia (p < 0.015). The association between anesthetic approach and perioperative myocardial ischemia or infarction remained after adjustment for preoperative factors associated with ischemia or with type of anesthesia. General anesthesia does not appear to be associated with increased risk of myocardial ischemia, and stringent recommendations to avoid it in this population may be unfounded. A clinical trial is needed to define more clearly the risks and benefits of different types of anesthesia in high-risk patients.     

Perioperative Kardioprotektion

Myocardial ischemia is a major cause of perioperative morbidity and mortality. Because of a growing expectancy of lives, the prevalence of cardiovascular diseases is increasing, and thus the number of surgical patients presenting with a cardiovascular risk profile. Based upon pathophysiological considerations, different interventions to lower perioperative cardiovascular risk have been evaluated. The mostly discussed intervention believed to prevent cardiovascular complications in the perioperative period is the use of beta-blockers. Although many authors agree that perioperative beta-blockade is effective in high-risk patients, less is known about the optimal timing, dosage and the identification of patients in whom the intervention would be beneficial. Based upon the available data we try to answer questions about timing and dosage, and we discuss possible side effects and economic questions. Another cardioprotective option is the use of statins. Besides their lipid-lowering properties, so called pleiotropic effects are believed to decrease cardiac risk. Furthermore, different interventions can be used in addition to or as an alternative to perioperative beta-blocker therapy, such as alpha-2 agonists, thoracic epidural analgesia or coronary revascularization.     

Perioperative cardioprotection. Golden standard beta-blockade?

Myocardial ischemia is a major cause of perioperative morbidity and mortality. Because of a growing expectancy of lives, the prevalence of cardiovascular diseases is increasing, and thus the number of surgical patients presenting with a cardiovascular risk profile. Based upon pathophysiological considerations, different interventions to lower perioperative cardiovascular risk have been evaluated. The mostly discussed intervention believed to prevent cardiovascular complications in the perioperative period is the use of beta-blockers. Although many authors agree that perioperative beta-blockade is effective in high-risk patients, less is known about the optimal timing, dosage and the identification of patients in whom the intervention would be beneficial. Based upon the available data we try to answer questions about timing and dosage, and we discuss possible side effects and economic questions. Another cardioprotective option is the use of statins. Besides their lipid-lowering properties, so called pleiotropic effects are believed to decrease cardiac risk. Furthermore, different interventions can be used in addition to or as an alternative to perioperative beta-blocker therapy, such as alpha-2 agonists, thoracic epidural analgesia or coronary revascularization.     

Regional versus general anesthesia in high-risk surgical patients: The need for a clinical trial

Regional anesthesia is often preferred over general anesthesia for patients with cardiovascular disease because of presumed decreased risk of perioperative myocardial ischemia. However, few studies have addressed this issue directly. To determine whether the type of anesthesia is independently associated with myocardial ischemia, records of 134 patients undergoing peripheral vascular grafting under general or regional anesthesia were examined. There were no significant differences preoperatively between groups in ASA class, age, sex, or prevalence of angina, diabetes, or hypertension. Twelve patients developed myocardial ischemia or infarction within 7 days of operation; 11 of these 12 patients had received regional anesthesia (p < 0.015). The association between anesthetic approach and perioperative myocardial ischemia or infarction remained after adjustment for preoperative factors associated with ischemia or with type of anesthesia. General anesthesia does not appear to be associated with increased risk of myocardial ischemia, and stringent recommendations to avoid it in this population may be unfounded. A clinical trial is needed to define more clearly the risks and benefits of different types of anesthesia in high-risk patients.     

Preoperative cardiac risk management

Approximately 100 million people undergo noncardiac surgery annually worldwide. It is estimated that around 3% of patients undergoing noncardiac surgery experience a major adverse cardiac event. Although cardiac events, like myocardial infarction, are major cause of perioperative morbidity or mortality, its true incidence is difficult to assess. The risk of perioperative cardiac complications depends mainly on two conditions: (1) identified risk factors, and (2) the type of the surgical procedure. On that basis, different scoring systems have been developed in order to accurately assess the perioperative cardiac risk and to improve the patient management. Importantly, patients with estimated high risk should be tested preoperatively by non-invasive cardiac imaging modalities. According to test results, they can proceed directly to planed surgery with the use of cardioprotective drugs (beta-blockers, statins, aspirin), or to myocardial revascularization prior to non-cardiac surgery. In this review, we discuss the role of clinical cardiac risk factors, laboratory measurements, additional non-invasive cardiac testing, and consequent strategies in perioperative management of patients undergoing noncardiac surgery.     

Cardiovascular events in patients undergoing hip fracture surgery treated with remote ischaemic preconditioning: 1-year follow-up of a randomised clinical trial

Remote ischaemic preconditioning reduces the risk of myocardial injury within 4 days of hip fracture surgery. We aimed to investigate the effect of remote ischaemic preconditioning on the incidence of major adverse cardiovascular events 1 year after hip fracture surgery. We performed a phase-2, multicentre, randomised, observer-blinded, clinical trial between February 2015 and September 2017. We studied patients aged ≥ 45 years with a hip fracture and a minimum of one cardiovascular risk factor. Patients were allocated randomly to remote ischaemic preconditioning applied just before surgery or no treatment (control group). Remote ischaemic preconditioning was performed on the upper arm with a tourniquet in four cycles of 5 min ischaemia and 5 min reperfusion. Primary outcome was the occurrence of major adverse cardiovascular events within 1 year of surgery. A total of 316 patients were allocated randomly to the remote ischaemic preconditioning group and 309 patients to the control group. Major adverse cardiovascular events occurred in 43 patients (13.6%) in the remote ischaemic preconditioning group compared with 51 patients (16.5%) in the control group (adjusted hazard ratio (95%CI) 0.83 (0.55–1.25); p = 0.37). Fewer patients in the remote ischaemic preconditioning group had a myocardial infarction (11 (3.5%) vs. 22 (7.1%); hazard ratio (95%CI) 0.48 (CI 0.23–1.00); p = 0.04). Remote ischaemic preconditioning did not reduce the occurrence of major adverse cardiovascular events within 1 year of hip fracture surgery. The effect of remote ischaemic preconditioning on clinical cardiovascular outcomes in non-cardiac surgery needs confirmation in appropriately powered randomised clinical trials.     

Review article: The role of statins in reducing perioperative cardiac risk: physiologic and clinical perspectives

PURPOSE: To review the pathobiology and clinical implications of coronary vulnerable atherosclerotic plaques (VAPs), to discuss the role of statin therapy in VAP stabilization, and the potential benefits of perioperative statin therapy (PST) in reducing perioperative risk of acute coronary syndromes (ACSs). SOURCE: MEDLINE search using "perioperative", "cardiac morbidity", "atherosclerosis", "vulnerable plaque", "statins" and combinations of these terms as keywords. The reference lists of relevant articles were further reviewed to identify additional citations. PRINCIPAL FINDINGS: The nonstenotic, yet rupture-prone VAP causes most myocardial infarctions (MIs) and other ACSs, both in the nonsurgical and surgical patients. Large clinical trials in both primary and secondary prevention and in patients with ACSs have demonstrated that statin therapy will reduce cardiovascular morbidity and mortality across a broad spectrum of patient subgroups. These trials also suggest, and laboratory investigations establish, that statins possess favourable vascular effects independent of cholesterol reduction. Statins appear to interfere specifically with the pathophysiologic mechanisms implicated in atherothrombotic disease. Statins reduce vascular inflammation, improve endothelial function, stabilize VAPs, and reduce platelet aggregability and thrombus formation. Recent studies have shown that PST is associated with a reduced incidence of perioperative and long-term cardiovascular complications in high-risk patients. Combined therapy with statins and ss-blockers is a conceptually valid strategy targeting critical steps in the pathogenesis of an ACS. CONCLUSION: Emerging evidence for the efficacy and safety of PST is promising, especially when combined with ss-blocker therapy in patients at highest risk. Confirmation of this early evidence awaits the results of ongoing and future prospective randomized controlled trials.     

Remote ischemic preconditioning in major vascular surgery

Remote ischemic preconditioning is a physiologic mechanism in mammalian species whereby brief exposure to nonlethal ischemia in one tissue confers protection against a prolonged ischemic insult in a distant tissue. First described almost 15 years ago, it has been slow to translate into clinical practice. Several clinical trials have recently reported that remote ischemic preconditioning reduces myocardial injury after major cardiovascular surgery. In addition, a randomized trial in patients undergoing open abdominal aortic aneurysm repair reported a significant reduction in perioperative myocardial infarctions. Remote ischemic preconditioning is easily performed and likely to prove highly cost-effective. large-scale trials of the technique are warranted in patients undergoing major vascular surgery.     

The influence of aneurysm size on perioperative cardiac outcome in elective open infrarenal aortic aneurysm repair

BACKGROUND: Abdominal aortic aneurysm (AAA) size and growth has been found to be associated with local generation of inflammation markers such as interleukin-6. Inflammation also seems to be important in perioperative adverse cardiac events. We hypothesized that patients with a large AAA are at increased risk for cardiac events. METHODS: Consecutive patients who underwent a computed tomography angiography scan before open elective infrarenal AAA repair between March 2000 and December 2005 at three hospitals were analyzed. All patients were screened for the clinical risk factors of age, gender, angina pectoris, myocardial infarction, heart failure, diabetes, stroke, renal failure, and chronic obstructive pulmonary disease, as well as for cardioprotective medication. Postoperative data on troponin release, creatine kinase/creatine kinase isoenzyme MB, and electrocardiogram were routinely collected on days 1, 3, 7, and 30. The main outcome measure was the combined end point of 30-day cardiovascular death and nonfatal myocardial infarction. Multivariate Cox regression analysis was used to evaluate the influence of AAA size on postoperative cardiac outcome. RESULTS: The study included 500 patients. Their mean age was 69.8 +/- 9.5 years, and 431 (86%) were men. Thirty-one patients (6.2%) had perioperative cardiovascular complications, consisting of 15 (3.0%) cardiovascular deaths and 16 (3.2%) nonfatal myocardial infarctions. After correction for other risk factors, including age, Revised Cardiac Risk Index, medication use, duration of surgery, and intraoperative blood loss, AAA size was independently associated with perioperative nonfatal myocardial infarction and cardiovascular death (3.2% increase in risk for each millimeter added, 95% confidence interval 1.1% to 6.2%, P = .007). CONCLUSION: A larger AAA size is independently associated with an increased incidence of perioperative cardiovascular complications after elective infrarenal AAA repair.     

Die Bedeutung der perioperativen medikamentösen Therapie für das Ergebnis gefäßchirurgischer Operationen

Cardiac complications after vascular surgery are specific to the patient, the surgery itself, and the circumstances under which surgery was performed. Myocardial infarction and congestive heart failure are the major causes of perioperative morbidity and mortality in patients with cardiac comorbidities undergoing major vascular surgery. The perioperative medical treatment of patients presenting with cardiovascular risk factors is aimed at reducing the incidence of postoperative complications—in an increasing number of patients, due to increasing life expectancy. This paper discusses the impact of beta blockers, statins, and other medical therapy on the prevention of perioperative morbidity. Although it is generally accepted that preoperative treatment with beta blockers constitutes effective prevention of postoperative cardiac complications in high-risk patients, data are needed in order to derive guiding principles addressing the type and duration of beta blocker therapy. Statins are another group of cardioprotective medications that offer, besides lipid-lowering effects, stabilization of atherosclerotic plaque. The effects of alpha-2 agonists and antiplatelet therapy are also discussed.     

Regional anesthesia in cardiac surgery: a friend or a foe?

Escalating costs and change in the profile of patients presenting for cardiac surgery requires modification of perioperative management strategies. Regional anesthesia has played an integral part of many fast-track anesthesia protocols across North America and Europe. This review suggests that for patients undergoing coronary artery bypass graft surgery, the risk-to-benefit ratio is in favor of epidural and spinal anesthesia, provided there are no specific contraindications and the guidelines for the use of regional techniques in cardiac surgery are followed. Patients managed with regional techniques seem to benefit from superior postoperative analgesia, shorter postoperative ventilation, reduced incidence of supraventricular arrhythmia, and lower rates of perioperative myocardial infarction. The results of this analysis suggest that for each episode of neurologic complication, 20 myocardial infarctions and 76 episodes of atrial fibrillation would be prevented, thus, we would consider the regional anesthesia and analgesia to be an effective strategy that improves perioperative morbidity. However, other treatment modalities such as the addition of calcium channel blockers, aspirin, and beating heart surgery, are also suggested to be beneficial in cardiac surgical patients and may impose less risk than the use of regional techniques. We believe that the results presented in this review are encouraging enough to permit continued investigation. A prospective, randomized, controlled multicenter trial needs to be adequately powered to answer important clinical questions and allow for a long-term follow-up.     

Neue Aspekte der perioperativen Statintherapie

Statins are effective drugs for treatment and prevention of cardiovascular diseases. Besides their lipid-lowering properties, statins act through multiple pleiotropic effects including vasoprotective mechanisms, effects on coagulation, anti-inflammatory properties and stabilization of atherosclerotic plaques. In recent years many studies have investigated the effects of statins administered to patients in the perioperative period. Results indicate that the perioperative use of statins is beneficial, most of all for patients with a high cardiovascular risk profile. However, most study designs are retrospective and vulnerable to systematic bias. The number of randomized controlled trials is very limited and include only low numbers of patients. Currently it is not known when perioperative treatment with statin should be started and how long it should be continued postoperatively to reach optimal protective effects. A pre-existing statin therapy should be continued perioperatively because discontinuation leads to a higher rate of complications in the perioperative period. Larger randomized controlled trials are therefore necessary to evaluate the efficiency and the safety of perioperative statin use, especially for patients with a low or intermediate cardiovascular risk profile.     

QTc dispersion is prolonged in patients with early postoperative adverse cardiovascular events and those with silent myocardial ischemia

OBJECTIVE: To determine if increased QT interval dispersion (corrected and not corrected for heart rate) is associated with perioperative silent myocardial ischemia or postoperative adverse cardiovascular events. DESIGN: Blinded retrospective observational study. SETTING: University hospital. PARTICIPANTS: One hundred eighty-one perioperative patients receiving general anesthesia for elective major vascular or orthopedic surgery. INTERVENTIONS: None. MEASUREMENTS AND MAIN RESULTS: QT dispersion, corrected and uncorrected for heart rate, was prolonged in patients suffering significant myocardial ischemia up to 48 hours assessed by Holter ECG monitoring, for early cardiac morbidity and all early cardiac events (including mortality) up to 1 month postoperatively. There were no significant changes in patients showing early cardiovascular mortality or late cardiac morbidity or mortality between 1 and 12 months postoperatively. Morbidity and mortality were determined from clinical notes, laboratory investigations, and autopsy when available. QT dispersion performed poorly as a screening test to identify those who subsequently developed early adverse cardiovascular outcomes. CONCLUSIONS: QT dispersion is prolonged in those at risk of early adverse cardiovascular events but is a poor screening tool.     

Intravenous anesthesia for the patient with left ventricular dysfunction

Patients with heart failure have a diminished cardiac reserve capacity that may be further compromised by anesthesia. In addition to depression of sympathetic activity, most anaesthetics interfere with cardiovascular performance, either by a direct myocardial depression or by modifying cardiovascular control mechanisms. Etomidate causes the least cardiovascular depression. It is popular for induction of anesthesia in cardiac-compromised patients; however, it is not suitable for maintenance of anesthesia because it depresses adrenocortical function. Ketamine has a favorable cardiovascular profile related to central sympathetic stimulation and inhibition of neuronal catecholamine uptake. These counteract its direct negative inotropic effect. In patients with a failing myocardium, however, the negative inotropic effects may be unmasked, resulting in deterioration in cardiac performance and cardiovascular instability. Propofol is the most popular intravenous anesthetic for maintenance of anesthesia. It does have a negative inotropic effect, but the net effect on myocardial contractility is insignificant at clinical concentrations, probably because of a simultaneous increase in the sensitivity of the myofilaments to Ca2+. Propofol protects the myocardium against ischemia-reperfusion injury, an action derived from its antioxidant and free-radical-scavenging properties as well as the related inhibition of the mitochondrial permeability transition pore. For intravenous anesthesia, propofol is always combined with an opioid. Opioids have relatively few cardiovascular side effects and, in particular, do not cause myocardial depression. Indeed, they are cardioprotective, with antiarrhythmic activity, and induce pharmacologic preconditioning of the myocardium by a mechanism similar to the inhalational anesthetics.     

瑞芬太尼心肌保护作用的研究进展

背景瑞芬太尼是一超短效阿片受体激动剂,可有效抑制心血管应激反应,维持血液动力学稳定;研究发现瑞芬太尼预处理及后处理可减轻心肌缺血/再灌注损伤（ischemia/reperfusion injury,I/RI）。目的就瑞芬太尼心肌保护作用的研究进展作一综述,使人们系统地了解瑞芬太尼的心肌保护作用及其可能机制。内容主要从瑞...