Perioperative cardiac damage in vascular surgery patients.

BACKGROUND: Patients undergoing vascular surgery are at increased risk for developing cardiac complications. Majority of patients with perioperative myocardial damage are asymptomatic. Our objective is to review the available literature addressing the prevalence and prognostic implications of perioperative myocardial damage in vascular surgery patients. METHODS: An Internet-based literature search was performed using MEDLINE to identify all published reports on perioperative myocardial damage in vascular surgery patients. Only those studies published from 2000 to 2010 evaluating myocardial damage using troponin I or T, with or without symptoms of angina pectoris were included. RESULTS: Thirteen studies evaluating the prevalence of perioperative myocardial ischaemia or infarction were included in the study. The incidence of perioperative myocardial ischaemia ranged from 14% to 47% and the incidence of perioperative myocardial infarction ranged from 1% to 26%. In addition, 10 studies evaluating the prognostic value of perioperative myocardial ischaemia towards postoperative mortality or the occurrence of major adverse cardiac events were included. In the retrieved studies, hazard ratios varied from 1.9 to 9.0. CONCLUSION: The high prevalence and asymptomatic nature of perioperative myocardial damage, combined with a substantial influence on postoperative mortality of vascular surgery patients, underline the importance of early detection and adequate management of perioperative myocardial damage. This article provides an extended overview regarding the prevalence and prognostic value of perioperative myocardial ischaemia and infarction in vascular surgery patients. In addition, treatment options to reduce the risk of perioperative myocardial damage are provided based on the current available literature.

Asymptomatic low ankle-brachial index in vascular surgery patients: a predictor of perioperative myocardial damage.

OBJECTIVES: This study evaluated the prognostic value of asymptomatic low ankle-brachial index (ABI) to predict perioperative myocardial damage, incremental to conventional cardiac risk factors imbedded in cardiac risk indices (Revised Cardiac index and Adapted Lee index). MATERIALS AND METHODS: Preoperative ABI measurements were performed in 627 consecutive vascular surgery patients (carotid artery or abdominal aortic aneurysm repair). An ABI<0.90 was considered abnormal. Patients with ABI>1.40 or (a history of) intermittent claudication were excluded. Serial troponin-T measurements were performed routinely before and after surgery. The main study endpoint was perioperative myocardial damage, the composite of myocardial ischaemia and infarction. Multivariate regression analyses, adjusted for conventional risk factors, evaluated the relation between asymptomatic low ABI and perioperative myocardial damage. RESULTS: In total, 148 (23%) patients had asymptomatic low ABI (mean 0.73, standard deviation+/-0.13). Perioperative myocardial damage was recorded in 107 (18%) patients. Multivariate regression analyses demonstrated that asymptomatic low ABI was associated with an increased risk of perioperative myocardial damage (odds ratio (OR): 2.4, 95% CI: 1.4-4.2) CONCLUSIONS: This study demonstrated that asymptomatic low ABI has a prognostic value to predict perioperative myocardial damage in vascular surgery patients, incremental to risk factors imbedded in conventional cardiac risk indices.

Prognosis of vascular surgery patients using a quantitative assessment of troponin T release: is the crystal ball still clear?

BACKGROUND: Cardiac troponin T (cTnT) assays with increased sensitivity might increase the number of positive tests. Using the area under the curve (AUC) with serial sampling of cTnT an exact quantification of the myocardial damage size can be made. We compared the prognosis of vascular surgery patients with integrated cTnT-AUC values to continuous and standard 12-lead electrocardiography (ECG) changes. METHODS: 513 Patients were monitored. cTnT sampling was performed on postoperative days 1, 3, 7, 30 and/or at discharge or whenever clinically indicated. If cTnT release occurred, daily measurements of cTnT were performed, until baseline was achieved. CTnT-AUC was quantified and divided in tertiles. All-cause mortality and cardiovascular events (cardiac death and myocardial infarction) were noted during follow-up. RESULTS: 81/513 (16%) Patients had cTnT release. After adjustment for gender, cardiac risk factors, and site and type of surgery, those in the highest cTnT-AUC tertile were associated with a significantly worse cardiovascular outcome and long-term mortality (HR 20.2; 95% CI 10.2-40.0 and HR 4.0; 95% CI 2.0-7.8 respectively). Receiver operator analysis showed that the best cut-off value for cTnT-AUC was <0.01 days*ng m for predicting long-term cardiovascular events and all-cause mortality. CONCLUSION: In vascular surgery patients quantitative assessment of cTnT strongly predicts long-term outcome.

Perioperative blood glucose monitoring and control in major vascular surgery patients.

Diabetes mellitus (DM) is an independent predictor for morbidity and mortality in the general population, which is even more apparent in patients with concomitant cardiovascular risk factors. As the prevalence of DM is increasing, with an ageing general population, it is expected that the number of diabetic patients requiring surgical interventions will increase. Perioperative hyperglycaemia, without known DM, has been identified as a predictor for morbidity and mortality in patients undergoing surgery. Moreover, early studies showed that intensive blood-glucose-lowering therapy reduced both morbidity and mortality among patients admitted to the postoperative intensive care unit (ICU). However, later studies have doubted the benefit of intensive glucose control in medical-surgical ICU patients. This article aims to comprehensively review the evidence on the use of perioperative intensive glucose control, and to provide recommendations for current clinical practice. A systematic review was performed of the literature on perioperative intensive glucose control. Based on this literature review, we observed that intensive glucose control in the perioperative period has no clear benefit on short-term mortality. Intensive glucose control may even have a net harmful effect in selected patients. In addition, concerns on the external validity of some studies are important barriers for widespread recommendation of intensive glucose control in the perioperative setting. We propose that guidelines recommending intensive glucose control should be re-evaluated. In addition, moderate tight glucose control should currently be regarded as the safest and most efficient approach to patients undergoing major vascular surgery.

The prevalence of polyvascular disease in patients referred for peripheral arterial disease.

OBJECTIVE: To objectively assess the presence of polyvascular disease in patients with peripheral arterial disease and its relation to inflammation and clinical risk factors. METHODS: A total of 431 vascular surgery patients (mean age 68 years, men 77%) with atherosclerotic disease were enrolled. The presence of atherosclerosis was assessed using ultrasonography. Affected territories were defined as: (1) carotid, stenosis of common or internal carotid artery of >or=50%, (2) cardiac, left ventricular wall motion abnormalities, (3) abdominal aorta, diameter >or=30 mm and (4) lower limb, ankle-brachial pressure index <0.9. Cardiovascular risk factors and high-sensitivity C-reactive protein (hs-CRP) levels were noted in all. RESULTS: One vascular territory was affected in 29% of the patients, whereas polyvascular disease was found in 71%: two affected territories in 45%, three in 23% and four in 3% of patients. Levels of hs-CRP increased with the number of affected vascular territories (p<0.001). Multivariable logistic regression analysis showed age >or=70 years, male gender, body mass index (BMI)>or=25 kg m(-2), and hs-CRP to be independently associated with polyvascular disease. CONCLUSION: Polyvascular disease is a common condition in patients who have undergone vascular surgery. The level of systemic inflammation, reflected by hs-CRP levels, is moderately associated with the extent of polyvascular disease.

Coronary artery disease in patients with abdominal aortic aneurysm: a review article.

Abdominal aortic aneurysms (AAA) and coronary artery disease (CAD) have traditionally been regarded as two separate vessel disorders with a common background. Atherosclerosis has always been considered as the basic pathophysiologic process. However, during the last decade, evidence has emerged with differences between AAA and CAD. Firstly, data regarding the prevalence of AAA and CAD are different. Secondly, the risk profiles between AAA and CAD differ, mainly regarding gender, age and diabetes mellitus. Thirdly, despite the intensive treatment of CAD and improved outcome, the prevalence of AAA has not changed during the last decade. In this review we will discuss the characteristics of CAD in patients with AAA. In the first part we focus on epidemiological data of CAD in AAA patients. The pathophysiology of both AAA and CAD will be described in the second part. There is a common pathway between pathophysiology and risk profiles that is discussed in the third chapter. Based on the presence of risk factors and their influence on cardiovascular events, the preoperative work-up and testing for CAD in AAA has gained an important role. The role of (non)-invasive testing will be described in the fourth chapter. The treatment of AAA traditionally consisted solely of surgery. However, due to the influence of CAD on adverse outcomes, medical intervention is potentially useful. Surgical approaches for the treatment of both AAA and CAD, and most importantly, their influence on long-term outcome will be discussed in the fifth chapter.

The influence of statins on the expansion rate and rupture risk of abdominal aortic aneurysms.

Abdominal aortic aneurysms (AAA) have a prevalence between 1.3-8.9% in men and 1.0-2.2% in women aged above 55 years. Furthermore, AAA cause 1-3% of all deaths among men aged 65-85 years in developed countries. As the disorder is invariably associated with severe atherosclerotic damage of the arterial wall, it has traditionally been regarded as a direct consequence of generalized atherosclerotic disease. In patients with occlusive aortic disease, dyslipidemia is a well established risk factor. However, in patients with aneursymatic aortic disease, the association between dyslipidemia and the development of AAA is less clear. Large clinical trials in patients with cardiac and peripheral arterial disease have shown the strong relation between dyslipidemia, statin therapy and the risk of cardiovascular disease. Importantly, the effects of statin therapy were still present irrespective of the decrease in serum cholesterol levels. These findings resulted in the discussion of potential non-lipid lowering effects of statin therapy. These ''pleiotropic effects'' compose a diversity of cellular events which have an effect on several components of the arterial wall, including: 1) endothelial cells; 2) smooth muscle cells; 3) platelets; 4) monocytes/macrophages; and 5) the process of inflammation. In the general population the role of dyslipidemia as an independent risk factor for AAA is debated. However, as patients with AAA frequently have concomitant arterial disease, statin therapy is often recommended. As a result, the non-lipid lowering effects of statins on aneurysm expansion rate are hardly studied, and most evidence comes from experimental and animal studies. In the current review article we provide an overview of all available literature on the effects of dyslipidemia, statin therapy and the risk of AAA expansion and rupture. In the first part we summarize all population-based studies that investigated the relation between hypercholesterolemia and the development of AAA. In the second part, the available literature regarding the effects of statins on aneurysm growth, expansion rate and the risk of rupture is summarized, including in vitro, animal and clinical human studies.