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.

β-Blockers improve outcomes in kidney disease patients having noncardiac vascular surgery

Beta-blockers are known to improve postoperative outcome after major vascular surgery. We studied the effects of beta-blockers in 2126 vascular surgery patients with and without kidney disease followed for 14 years. Creatinine clearance was calculated using the Cockcroft-Gault equation, and kidney function was categorized as Stage 1 for a reference group of 550 patients, Stage 2 with 808 patients, Stage 3 with 627 patients, and combined Stages 4 and 5 with 141 patients. Outcome measures were 30-day and long-term all-cause mortality with a mean follow-up of 6 years. Cox proportional hazards models were used to control cardiovascular risk factors, including propensity for beta-blocker use. In all, 129 (6%) and 1190 (56%) patients died respectively. Mortality rates were three- and two-fold higher, respectively, for patients at Stages 3-5 compared to the reference group for the two outcomes. beta-Blocker use was significantly associated with a lower risk of mortality after surgery. The overall adjusted hazard ratio was 0.35 and 0.62, respectively, for individuals at Stages 3-5 compared to the reference group for 30-day and long-term mortality. This study shows that kidney function is a predictor of all-cause mortality and beta-blocker use is associated with a lower risk of death in kidney disease patients undergoing elective vascular surgery.

The Influence of Aging on the Prognostic Value of the Revised Cardiac Risk Index for Postoperative Cardiac Complications in Vascular Surgery Patients

OBJECTIVE

The Lee-risk index [Lee-index] was developed to predict major adverse cardiac events [MACE]. However, age is not included as a risk factor. The aim was to assess the value of the Lee-index in vascular surgery patients among different age categories.

METHODS

Of 2642 patients cardiovascular risk factors were noted to calculate the Lee-index. Patients were divided into four age categories; < or = 55 (n=396), 56-65 (n=650), 66-75 (n=1058) and > 75 years (n=538). Outcome measures were postoperative MACE (cardiac death, MI, coronary revascularization and heart failure). The performance of the Lee-index was determined using C-statistics within the four age groups.

RESULTS

The incidence of MACE was 10.9%, for Lee-index 1, 2 and > or = 3; 6%, 13% and 20%, respectively. However, the prognostic value differed among age groups. The predictive value for MACE was highest among patients under 55 year (0.76 vs 0.62 of patients aged > 75). The prediction of MACE improved in elderly (aged > 75) after adjusting the Lee-index with age, revised risk of operation (low, low-intermediate, high-intermediate and high-risk procedures) and hypertension (0.62 to 0.69).

CONCLUSION

The prognostic value of the Lee-index is reduced in elderly vascular surgery patients, adjustment with age, risk of surgical procedure, and hypertension improves the Lee-index significantly.

Cardiac risk in non-cardiac surgery

Beta blocker, statin and aspirin advocated

Prognostic Significance of Declining Ankle-brachial Index Values in Patients with Suspected or Known Peripheral Arterial Disease

BACKGROUND

Peripheral arterial disease (PAD) is a risk factor for cardiovascular events. This study assessed the prognostic significance of repeated ankle-brachial index (ABI) measurements at rest and after exercise in patients with PAD receiving conservative treatment.

METHODS

In a cohort study of 606 patients (mean age 62+/-12 years, 68% male), ABI at rest and after exercise was measured at baseline and after 1 year. Patients with reductions in ABI were divided into three equally-sized groups (minor, intermediate and major reductions) and were compared to patients without reductions. During a mean follow-up of 5+/-3 years, all-cause mortality, cardiac events, stroke and progression to kidney failure were noted.

RESULTS

Death was recorded in 83 patients (14%) of which 49% were due to cardiac causes. Non-fatal myocardial infarction occurred in 38 patients (6%), stroke in 46 (8%) and progression to kidney failure in 35 (6%). By multivariate analysis, patients with major declines in resting (>20%) and post-exercise (>30%) ABI were at increased risk of all-cause mortality (HR: 3.3, 95% CI: 1.5-7.2, HR: 3.0, 95% CI: 1.4-6.4, respectively), cardiac events (HR: 3.1, 95% CI: 1.3-7.2, HR: 2.4, 95% CI: 1.1-5.6, respectively), stroke (HR: 4.2, 95% CI: 1.6-10.4, HR: 3.9, 95% CI: 1.4-10.2, respectively) and kidney failure (HR: 2.7, 95% CI: 1.1-7.5, HR: 6.9, 95% CI: 1.5-31.5, respectively), compared to patients with no declines in ABI.

CONCLUSIONS

This study shows that major 1-year declines in resting and post-exercise ABI are associated with all-cause mortality, cardiac events, stroke and kidney failure in patients with PAD.

Myocardial Damage in High-risk Patients Undergoing Elective Endovascular or Open Infrarenal Abdominal Aortic Aneurysm Repair

OBJECTIVE

Dobutamine stress echocardiography (DSE) provides an objective assessment of the presence and extent of coronary artery disease. Therefore we compared cardiac outcome in patients at high-cardiac risk undergoing open or endovascular repair of infrarenal AAA using preoperative DSE results.

METHODS

Consecutive patients with >or=3 cardiac risk factors (age >70 years, angina pectoris, myocardial infarction, heart failure, stroke, renal failure, and diabetes mellitus) undergoing infrarenal AAA repair were reviewed retrospectively. All underwent cardiac stress testing using DSE. Postoperatively data on troponin release and ECG were collected on day 1, 3, 7, before discharge, and on day 30. The main outcome measures were perioperative myocardial damage and myocardial infarction or cardiovascular death.

RESULTS

All 77 patients (39 endovascular, 38 open) had a history of cardiac disease. The number and type of cardiac risk factors were similar in both groups. Also DSE results were similar: 55 vs 56%, 24 vs 28%, and 21 vs 18% had no, limited, or extensive stress induced myocardial ischemia respectively. The incidence of perioperative myocardial damage (47% vs 13%, p=0.001) and the combination of myocardial infarction or cardiovascular death (13% vs 0%, p=0.02) was significantly lower in patients receiving endovascular repair.

CONCLUSION

In patients with similar high cardiac risk, endovascular repair of infrarenal aortic aneurysms is associated with a reduced incidence of perioperative myocardial damage.

Abdominal Aortic Aneurysm Screening Using Non-imaging Hand-held Ultrasound Volume Scanner – A Pilot Study

BACKGROUND

Screening for abdominal aortic aneurysms (AAA) is cost-effective and timely repair improves outcome. Using standard ultrasound (US) an AAA can be accurately diagnosed or ruled-out. However, this requires training and bulk equipment.

AIM

To evaluate the diagnostic potential of a new hand-held ultrasound bladder volume indicator (BVI) in the setting of AAA screening.

METHODS

In total, 94 patients (66 +/- 14 years, 67 men) referred for atherosclerotic disease were screened for the presence of AAA (diameter > 30 mm using US). All patients underwent both examinations, with US and BVI. Using the BVI, aortic volume was measured at 6 pre-defined points. Maximal diameters (US) and volumes (BVI) were used for analyses.

RESULTS

In 54 (57%) patients an AAA was diagnosed using US. The aortic diameter by US correlated closely with aortic volume by BVI (r = 0.87, p < 0.0001). Using a cut-off value of > or = 50 ml for the presence of AAA by BVI, sensitivity, specificity, positive and negative predictive value of BVI in detection of AAA were 94%, 82%, 88% and 92%, respectively. The agreement between the two methods was 89%, kappa 0.78.

CONCLUSION

The bladder volume indicator is a promising tool in screening patients for AAA.

Perioperative cardiac risk stratification and modification in abdominal aortic aneurysm repair

Cardiovascular complications are important causes of morbidity and mortality following vascular surgery. Adequate preoperative risk assessment and perioperative management may modify postoperative mortality and morbidity and improve long-term prognosis. The objective of this review is to examine the present day knowledge regarding the preoperative evaluation and perioperative management of patients undergoing noncardiac surgery, focusing specifically on abdominal aortic aneurysm (AAA) repair. Clinical markers combined with ECG and surgical risk assessment can effectively divide patients in a truly low-risk, intermediate and high-risk population. Low-risk patients can probably be operated on without additional cardiac testing. Notably, due to the surgical risk, AAA patients are never low-risk patients. Intermediate-risk and high-risk patients are referred for cardiac testing to exclude extensive stress induced myocardial ischemia, as beta-blockers provide insufficient myocardial protection in this case and preoperative coronary revascularization might be considered. Whether patients at intermediate risk without ischemic heart disease should be treated with statins and/or beta-blockers is still controversial. In high-risk patients, it is strongly advised to administer beta-blockers with heart rate determined dose adjustment, while the effects of preoperative revascularization remain subject to debate.

β-Blockers Improve In-hospital and Long-term Survival in Patients with Severe Left Ventricular Dysfunction Undergoing Major Vascular Surgery

OBJECTIVES

To study whether beta-blockers reduce in-hospital and long-term mortality in patients with severe left ventricular dysfunction (LVD) undergoing major vascular surgery.

DESIGN

Observational cohort study.

MATERIALS

Five hundred and eleven patients with severe LVD (ejection fraction<30%) undergoing major non-cardiac vascular surgery.

METHODS

In all patients, cardiac risk factors, medication (including beta-blockers), and dobutamine stress echocardiography (DSE) results were noted prior to surgery. DSE was evaluated for rest and stress-induced new wall motion abnormalities. Endpoint was in-hospital and long-term mortality. Propensity scores for beta-blockers were calculated and regression models were used to analyse the relation between beta-blockers and mortality.

RESULTS

Mean age was 64+/-11 years and 383 patients (75%) were male. 139 patients (27%) used beta-blockers. Stress-induced ischemia occurred in 82 patients (16%). Median follow-up was 7 years (interquartile range: 3-10). In-hospital and long-term mortality was observed in 64 (13%) and 171 (33%) patients, respectively. After adjusting for clinical variables, DSE results and propensity scores, beta-blockers were significantly associated with reduced in-hospital and long-term mortality (OR: 0.18, 95% CI: 0.04-0.74 and HR: 0.38, 95% CI: 0.22-0.65, respectively).

CONCLUSION

In patients with severe LVD undergoing major vascular surgery, the use of beta-blockers is associated with a reduced incidence of in-hospital and long-term postoperative mortality.

Statins are associated with a reduced infrarenal abdominal aortic aneurysm growth

OBJECTIVE

To evaluate the effect of statins on aneurysm growth in a group of consecutive patients under surveillance for infrarenal aortic aneurysms (AAA).

MATERIALS AND METHODS

All patients (59 statin users, 91 non-users) under surveillance between January 2002 and August 2005 with a follow-up for aneurysm growth of at least 12 months and a minimum of three diameter evaluations were retrospectively included in the analysis. Multiple regression analysis, weighted with the number of observations, was performed to test the influence of statins on AAA growth rate.

RESULTS

During a median period of 3.1 (1.1-13.1) years the overall mean aneurysm growth rate was 2.95+/-2.8 mm/year. Statin users had a 1.16 mm/year lower AAA growth rate compared to non-users (95% CI 0.33-1.99 mm/year). Increased age was associated with a slower growth (-0.09 mm/year per year, p = 0.003). Female gender (+1.82 mm/year, p = 0.008) and aneurysm diameter (+0.06 mm/year per mm, p = 0.049) were associated with increased AAA growth. The use of non-steroidal anti-inflammatory drugs, chronic lung disease, or other cardiovascular risk factors were not independently associated with AAA growth.

CONCLUSIONS

Statins appear to be associated with attenuation of AAA growth, irrespective of other known factors influencing aneurysm growth.

Ischemic heart disease in renal transplant candidates: towards non-invasive approaches for preoperative risk stratification

This editorial refers to the paper of R. Sharma et al. entitled "Dobutamine stress echocardiography and cardiac troponin T for the detection of significant coronary artery disease and predicting outcome in renal transplant candidates". The editorial discusses different strategies for cardiac risk assessment in patients with end-stage renal disease undergoing renal transplantation.

End-to-end Versus End-to-side Distal Anastomosis in Femoropopliteal Bypasses; Results of a Randomized Multicenter Trial

OBJECTIVE

To compare end-to-side (ETS) and end-to-end (ETE) distal anastomoses for femoropopliteal bypasses.

DESIGN

Prospective, randomized, multicenter trial.

METHODS

Patients from 14 centers were randomized to either ETS or ETE distal anastomosis, with stratification according to center and four categories: venous and prosthetic above knee bypass, and venous and prosthetic below knee bypass. Follow-up, with history, physical examination, ankle-brachial pressure index and duplex scan was performed at 3 months, 6 months and every 6 months thereafter until 36 months postoperatively.

RESULTS

A total of 328 femoropopliteal bypass operations were performed in 274 patients. Due to anatomical considerations at the time of surgery, 15 procedures (4.6%) were excluded from further analysis. Patient characteristics, cardiovascular risk factors, Rutherford classification and number of open run-off vessels were similar for both groups. Primary patency was 75 vs 74%, 65 vs 66% and 63 vs 55% for ETE vs ETS after 1, 2 and 3 years, respectively, (p = 0.26). During follow up major amputations were necessary in 20 ETE bypasses and in nine ETS bypasses (p = 0.028).

CONCLUSION

ETE distal anastomosis infemoropopliteal bypasses does not improve patency compared to ETS anastomosis. Major amputations, after failure of the bypass, were required more frequently for ETE distal anastomoses.

Flavonoids can replace alpha-tocopherol as an antioxidant

Endogenous antioxidants such as the lipid-soluble vitamin E protect the cell membranes from oxidative damage. Glutathione seems to be able to regenerate alpha-tocopherol via a so-called free radical reductase. The transient protection by reduced glutathione (GSH) against lipid peroxidation in control liver microsomes is not observed in microsomes deficient in alpha-tocopherol. Introduction of antioxidant flavonoids, such as 7-monohydroxyethylrutoside, fisetin or naringenin, into the deficient microsomes restored the GSH-dependent protection, suggesting that flavonoids can take over the role of alpha-tocopherol as a chain-breaking antioxidant in liver microsomal membranes.