Protecting the Heart with Cardiac Medication in Patients with Left Ventricular Dysfunction Undergoing Major Noncardiac Vascular Surgery

Patients with left ventricular dysfunction who are undergoing major noncardiac vascular surgery are at increased risk of adverse postoperative events. We sought to evaluate whether perioperative medication use, including angiotensin-converting enzyme (ACE) inhibitors,b-blockers, statins, and aspirin, was associated with a reduced incidence of postoperative in-hospital mortality in these high-risk patients. The study enrolled 511 patients with left ventricular dysfunction (left ventricular ejection fraction <30%) who were undergoing major noncardiac vascular surgery. Cardiac risk factors and medication use were noted before surgery. Preoperative dobutamine stress echocardiography (DSE) was performed to identify patients with stress-induced myocardial ischemia. The end point was postoperative in-hospital mortality. Univariate and multivariate logistic regression analyses were performed to evaluate the relation between perioperative medication use and mortality. The mean age of the study population was 64 ± 11 years, and 75% were men. Perioperative use of ACE inhibitors, b-blockers, statins, and aspirin was recorded in 215 (48%), 139 (27%), 107 (21%), and 125 patients (24%), respectively. Stress-induced myocardial ischemia occurred in 82 patients (16%). Sixty-four patients (13%) died. Perioperative use of ACE inhibitors (odds ratio [OR], 0.33; 95% confidence interval [CI], 0.12-0.91), b-blockers (OR, 0.03; 95% CI, 0.01-0.26), statins (OR, 0.06; 95% CI, 0.01-0.53), and aspirin (OR, 0.13; 95% CI, 0.03-0.55), was significantly associated with a reduced incidence of mortality, after adjusting for cardiac risk factors and DSE results. In conclusion, the present study showed that the perioperative use of ACE inhibitors,b-blockers, statins, and aspirin is independently associated with a reduced incidence of in-hospital mortality in patients with left ventricular dysfunction who are undergoing major noncardiac vascular surgery.

Decision-making in type-B dissection: current evidence and future perspectives

Aortic dissection is a devastating cardiovascular condition with an incidence of 3,5:100 000. It is classified according to anatomic extent, mechanism of lesion, duration from index event and course (uncomplicated vs. complicated). Intramural hematoma and penetrating aortic ulcers share many of the features of classic dissections, but tend to occur in older patients with advanced atherosclerosis. In uncomplicated type-B dissection, conservative treatment with tight blood pressure and heart rate control is safe and effective. Early stent-graft implantation may, however, result in more favorable aortic remodeling and reduced late complications. For acute complicated cases intervention is usually required. Stent-graft coverage of the entry tear frequently resolves malperfusion, but the role of the false lumen in organ perfusion must be assessed and endovascular revascularization performed if necessary. In chronic type-B dissections, coverage of the entry tear likely results in continued pressurization of the false lumen due to rigidity of the dissecting membrane and distal fenestrations. Better understanding of the different disease mechanisms involved, imaging advances and introduction of dedicated stent-grafts are expected to further improve patient outcomes in the future. Primary and secondary pharmacological prevention, stricter follow-up protocols and screening of family members may also prove valuable. Better patient selection will allow preventive treatment with low morbidity for those at higher risk of complications.

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.

Process of care partly explains the variation in mortality between hospitals after peripheral vascular surgery

OBJECTIVES

The aim of this study is to investigate whether variation in mortality at hospital level reflects differences in quality of care of peripheral vascular surgery patients.

DESIGN

Observational study.

MATERIALS

In 11 hospitals in the Netherlands, 711 consecutive vascular surgery patients were enrolled.

METHODS

Multilevel logistic regression models were used to relate patient characteristics, structure and process of care to mortality at 1 year. The models were constructed by consecutively adding age, sex and Lee index, then remaining risk factors, followed by structural measures for quality of care and finally, selected process of care parameters.

RESULTS

Total 1-year mortality was 11%, ranging from 6% to 26% in different hospitals. Large differences in patient characteristics and quality indicators were observed between hospitals (e.g., age>70 years: 28-58%; beta-blocker therapy: 39-87%). Adjusted analyses showed that a large part of variation in mortality was explained by age, sex and the Lee index (Akaike's information criterion (AIC)=59, p<0.001). Another substantial part of the variation was explained by process of care (AIC=5, p=0.001).

CONCLUSIONS

Differences between hospitals exist in patient characteristics, structure of care, process of care and mortality. Even after adjusting for the patient population at risk, a substantial part of the variation in mortality can be explained by differences in process measures of quality of care.

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.

Relation between regional and global systolic function in patients with ischemic cardiomyopathy after beta-blocker therapy or revascularization

BACKGROUND

To assess the relationship between improved regional and global myocardial function in patients with ischemic cardiomyopathy in response to beta-blocker therapy or revascularization.

MATERIALS AND METHODS

Cardiovascular magnetic resonance (CMR) was performed in 32 patients with ischemic cardiomyopathy before and 8 +/- 2 months after therapy. Patients were assigned clinically to beta-blocker therapy (n = 20) or revascularization (n = 12). CMR at baseline was performed to assess regional and global LV function at rest and under low-dose dobutamine. Wall thickening was analyzed in dysfunctional, adjacent, and remote segments. Follow-up CMR included rest function evaluation.

RESULTS

Augmentation of wall thickening during dobutamine at baseline was similar in dysfunctional, adjacent and remote segments in both patient groups. Therefore, baseline characteristics were similar for both patient groups. In both patient groups resting LV ejection fraction and end-systolic volume improved significantly (p < 0.05) at follow-up. Stepwise multivariate analysis revealed that improvement in global LV ejection fraction in the beta-blocker treated patients was significantly related to improved function of remote myocardium (p < 0.05), whereas in the revascularized patients improved function in dysfunctional and adjacent segments was more pronounced (p < 0.05).

CONCLUSION

In patients with chronic ischemic LV dysfunction, beta-Blocker therapy or revascularization resulted in a similar improvement of global systolic LV function. However, after beta-blocker therapy, improved global systolic function was mainly related to improved contraction of remote myocardium, whereas after revascularization the dysfunctional and adjacent regions contributed predominantly to the improved global systolic function.

The effect of statins on perioperative events in patients undergoing vascular surgery

Despite recent advancements in perioperative care and guideline recommendations, patients undergoing vascular surgery remain at risk for perioperative cardiovascular complications. In this review, the results are summarized of the most recent studies on the effectiveness and safety of perioperative statin use for the prevention of these perioperative cardiovascular complications. Perioperative statin therapy was associated with an improvement in postoperative cardiovascular outcome and a reduction in serum lipid levels and levels of inflammation markers.

Prognosis of transient new-onset atrial fibrillation during vascular surgery

BACKGROUND

Chronic atrial fibrillation (AF) in a non-surgical setting is associated with cardiovascular events. However, the prognosis of transient new-onset AF during vascular surgery is unknown.

OBJECTIVE

The purpose of this study is to investigate the prognosis of new-onset AF during vascular surgery using continuous electrocardiographic monitoring (continuous-ECG).

METHODS

In this study, 317 patients, all in sinus rhythm, scheduled for major vascular surgery were screened for cardiac risk factors. Continuous-ECG recordings for 72h and standard ECG on days 3, 7 and 30 were used to identify new-onset AF. Cardiac troponin T (cTnT) was measured routinely after surgery. Study endpoint was a composite of cardiac death, myocardial infarction, unstable angina and stroke (cardiovascular events) at 30 days after surgery and during late follow-up. Median follow-up was 12 (interquartile range 2-28) months.

RESULTS

New-onset AF was noted in 15 (4.7%) patients. All but three patients returned spontaneously to sinus rhythm. The composite endpoint of cardiovascular events within 30 days and during late follow-up occurred in 34 (11%) and 62 (20%) patients, respectively. Multivariate regression analysis showed that new-onset AF was associated with perioperative (hazard ratio (HR) 6.0; 95% CI: 2.4-15) and late cardiovascular events (HR 4.2, 95% CI: 2.1-8.8).

CONCLUSION

New-onset AF during vascular surgery is associated with an increased incidence of 30-day and late cardiovascular events.

Prognosis of patients with ischaemic cardiomyopathy after coronary revascularisation: relation to viability and improvement in left ventricular ejection fraction

BACKGROUND

In patients with ischaemic cardiomyopathy and viable myocardium, left ventricular ejection fraction (LVEF) does not always improve after revascularisation. Whether this may affect prognosis is unclear.

OBJECTIVE

To evaluate the prognosis of viable patients with and without improvement of LVEF after coronary revascularisation.

METHODS

Before revascularisation, radionuclide ventriculography (RNV) and dobutamine stress echocardiography were performed to assess LVEF and myocardial viability, respectively. Nine to 12 months after revascularisation, LVEF improvement was assessed by RNV. Patients were divided into three groups: group 1, viable patients with LVEF improvement (n = 27); group 2, viable patients without LVEF improvement (n = 15), group 3, non-viable patients (n = 48). Cardiac events were evaluated during a 4-year follow-up.

RESULTS

After revascularisation, the mean (SD) LVEF improved from 32 (9)% to 42 (10)% in group 1, but did not change significantly in group 2 and in group 3, p<0.001 by analysis of variance (ANOVA). Heart failure symptoms improved in both groups 1 (mean (SD) NYHA class from 3.1 (0.9) to 1.7 (0.7)) and 2 (from 3.2 (0.7) to 1.7 (0.9)), but not in group 3 (from 2.8 (1.0) to 2.7 (0.5)), p<0.001 by ANOVA. During follow-up, the cardiac event rate was low (4%) in group 1, intermediate (21%) in group 2 and high (33%) in group 3 (p = 0.01).

CONCLUSION

The best prognosis after revascularisation may be expected in those viable patients whose LVEF improves. Conversely, viable patients without functional improvement have an intermediate prognosis.

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 role of thrombin activatable fibrinolysis inhibitor in arterial thrombosis at a young age: the ATTAC study

BACKGROUND AND OBJECTIVES

Thrombin activatable fibrinolysis inhibitor (TAFI) attenuates fibrinolysis and may therefore contribute to the pathophysiology of arterial thrombosis. The aim of the present study was to elucidate the pathogenetic role of TAFI levels and genotypes in young patients with arterial thrombosis.

PATIENTS AND METHODS

In a case-control study, 327 young patients with a recent first-ever event of coronary heart disease (CHD subgroup) or cerebrovascular disease (ischemic stroke subgroup) and 332 healthy young controls were included. TAFI levels [intact TAFI, activation peptide (TAFI-AP) and (in)activated TAFI (TAFIa(i)] and TAFI activity were measured and genetic variations in the TAFI gene (-438G/A, 505G/A and 1040C/T) were determined.

RESULTS

In the total group of patients, TAFIa(i) levels were higher (145.1 +/- 37.5%) than in controls (137.5 +/- 31.3%, P = 0.02). Plasma levels of intact TAFI, TAFI-AP and TAFI activity were similar in patients and controls. In the CHD subgroup (n = 218), intact TAFI levels were higher (109.4 +/- 23.0%) than in controls (102.8 +/- 20.7%, P = 0.02). In 325Ile/Ile homozygotes, lower TAFI levels and a decreased risk of arterial thrombosis were observed (OR 0.58, 95% CI 0.34-0.99) compared with patients with the common 325Thr/Thr genotype. This association was most evident in CHD patients (OR 0.48, 95% CI 0.26-0.90). Haplotype analyses supported a role for the Thr325Ile polymorphism.

CONCLUSIONS

TAFIa(i) levels were higher in patients with cardiovascular disease. Furthermore, the TAFI 325Thr/Ile polymorphism was associated with lower TAFI levels and with the risk of cardiovascular disease in young patients, especially in CHD.

Prognosis of patients with peripheral arterial disease

The incidence of peripheral arterial disease (PAD) is on the increase and is associated with a major health concern in current practical care. The most common disease process underlying PAD is atherosclerosis. Atherosclerosis is a complex generalized disease affecting several arterial beds, including the peripheral and coronary circulation. Especially in patients with PAD, high incidences of coronary artery disease (CAD) have been observed, which may be asymptomatic or symptomatic. The prognosis of patients with PAD is related to the presence and extent of underlying CAD. In patients with PAD undergoing major vascular surgery, cardiac complications are the major cause of perioperative morbidity and mortality and indicate a high-risk for adverse long-term cardiac outcome. In order to improve outcome for PAD patients, assessment and aggressive therapy of atherosclerotic risk factors and usage of cardio-protective medications is recommended. Unfortunately, substantial differences in risk factor management and treatment and long-term outcome have been reported between PAD and CAD patients.

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.

[Perioperative risk reduction in vascular surgery via cardio-protective medication]

Cardiovascular complications are the leading cause of death after noncardiac surgery. Preoperative identification of patients with underlying coronary artery disease is important, and appropriate treatment strategies should be implemented in these patients in order to reduce the risk of perioperative complications. Based on recent findings, preoperative risk stratification models have been developed to identify high-, intermediate- or low-risk patients; the concentration of natriuretic peptides is a promising new preoperative risk marker. beta-blockers considerably reduce this risk. In clinical practice, important factors are adequate beta-blocker dosage, tight perioperative heart-rate control and continuation of beta-blockers after discharge. Recently, statins have emerged as drugs with perioperative cardioprotective properties, but more randomized clinical trials are needed before routine administration ofstatins can be recommended. Perioperative medical management should focus on improvements not only in the short-term but also in the long-term.

[Prevention of perioperative cardiac complications in non-cardiac surgery: an evidence-based guideline]

Approximately 2.5% of the patients undergoing non-cardiac surgery suffer from perioperative cardiac complications. These are associated with a mortality of 20.60%, a longer stay in hospital and higher costs. The risk factors for perioperative cardiac complications are: high-risk surgery, ischaemic heart disease, a history of congestive heart failure, cerebrovascular disease, diabetes, and renal failure. Recently, the scope of medical management has shifted from assessing and treating underlying culprit coronary lesions toward coronary plaque stabilisation and prevention of myocardial oxygen supply demand mismatch. Currently, the prevention of cardiac problems consists of identification of the patients at risk, optimisation of the preoperatieve condition by modification of underlying risk factors, optimisation of the perioperative medication with adrenergic beta-antagonists, statins, and acetylsalicylic acid, adequate perioperative monitoring and measures to prevent myocardial ischaemia. These include adequate sedation and analgesia, adequate oxygenation, oxygen transport, and ventilation, and if necessary additional cardiac medication.

Long-term cardiac outcome in high-risk patients undergoing elective endovascular or open infrarenal abdominal aortic aneurysm repair

OBJECTIVES

To assess long-term outcome of patients at high cardiac risk undergoing endovascular or open AAA repair.

METHODS

Patients undergoing open or endovascular infrarenal AAA repair with >or=3 cardiac risk factors and preoperative cardiac stress testing (DSE) at 2 university hospitals were studied. Main outcome was cardiac event free and overall survival. Multivariate Cox regression analysis was used to evaluate the influence of type of AAA repair on long-term outcome.

RESULTS

In 124 patients (55 endovascular, 69 open) the number and type of cardiac risk factors, medication use and DSE results were similar in both groups. In multivariable analysis, adjusting for cardiac risk factors, stress test results, medication use, and propensity score endovascular repair was associated with improved cardiac event free survival (HR 0.54; 95% CI 0.30-0.98) but not with an overall survival benefit (HR 0.73; 95% CI 0.37-1.46). Importantly, statin therapy was associated with both improved overall survival (HR 0.42; 95% CI 0.21-0.83) and cardiac event free survival (HR 0.45; 95% CI 0.23-0.86).

CONCLUSIONS

The perioperative cardiac benefit of endovascular AAA repair in high cardiac risk patients is sustained during long-term follow-up provided patients are on optimal medical therapy but it is not associated with improved overall long-term survival.

Prolonged-release nicotinic acid in patients with atherosclerotic disease in the Netherlands

OBJECTIVES

High-density lipoprotein (HDL) cholesterol elevation is associated with an improved outcome in patients with atherosclerotic disease. Niaspan, a prolonged-release nicotinic acid, was evaluated during the Niaspan-Induced HDL Elevation for Optimizing Risk Control (NEMO) study in The Netherlands.

METHODS

NEMO was a 6-month, prospective, observational, multicentre, open-label study. Niaspan was prescribed in statin-treated patients with known or suspected atherosclerotic disease. The main outcome measures were treatment-related adverse drug reactions (ADRs) and effects on lipids and cardiovascular-risk score based on the algorithm derived from the Prospective Cardiovascular Münster study.

RESULTS

612 patients were included in The Netherlands. Flushing was the most common ADR (29% of patients during the first month of treatment). The main reasons for treatment discontinuation were flushing (10.5%), patient request (8.0%) and being lost to follow-up (6.0%). About half of all patients (52%) continued treatment after the study. Tolerability was rated 'good' or 'very good' in 54% of these patients. HDL cholesterol increased by 23% from baseline, and triglycerides were reduced by 16%, with little change in low-density lipoprotein or total cholesterol. Cardiovascular risk score was reduced by 3.3 points.

CONCLUSIONS

The use of the prolonged-release nicotinic acid Niaspan in patients with or at risk for atherosclerotic disease showed good tolerability, a marked increase in HDL cholesterol and a reduced cardiovascular risk score.

A numerical model to predict abdominal aortic aneurysm expansion based on local wall stress and stiffness

Aneurysms of the abdominal aorta enlarge until rupture occurs. We assume that this is the result of remodelling to restore wall stress. We developed a numerical model to predict aneurysm expansion based on this assumption. In addition, we obtained aneurysm geometry of 11 patients from computed tomography angiographic images to obtain patient specific calculations. The assumption of a wall stress related expansion indeed resulted in a series of local expansions, adjusting global geometry in an exponential fashion similar as in patients. Furthermore, it revealed that location of peak wall stress changed over time. The assumptions of this model are discussed in detail in this manuscript, and the implications are related to literature findings.