Risk Chart for Future Mortality and Ischaemic Events Following Peripheral Bypass Surgery.

OBJECTIVES: A prediction model to identify determinants and quantify the risk of future ischaemic events in patients with peripheral arterial disease (PAD) provides a personal risk profile to offer individualized patient care. A risk chart was derived and validated in patients who received infrainguinal bypass surgery. METHODS: The Bypass Oral anticoagulants or Aspirin Risk Chart (BOA-RC2) was based on a pre-defined subgroup of the Dutch BOA trial (N = 482), the derivation cohort. The primary outcome event for BOA-RC2 was the composite of all cause death, non-fatal myocardial infarction, or non-fatal ischaemic stroke during a 10 year follow up. Determinants and long-term risk were identified with multivariate Cox regression analyses. Validation of the BOA-RC2 was performed in the remaining patients of the complete BOA trial cohort (N = 2,650 - 482 = 2,168), the validation cohort. RESULTS: The primary outcome event occurred in 67% (321/454) of the derivation cohort and in 66% (1,371/2,083) of the validation cohort during a median follow up of 6.6 years. The BOA-RC2 included the following determinants: age, critical limb ischaemia, diabetes, and a prior vascular intervention. The performance of the BOA-RC2 was good with a Brier score of 0.19, an area under the curve of 0.73, and a Hosmer-Lemeshow statistic of p = .9. CONCLUSIONS: The BOA-RC2 proves to be fit for the prediction of mortality and major ischaemic events in patients after peripheral bypass surgery. The BOA-RC2 can be used to adequately inform the patient about his/her risk of future events in an illustrative manner and stress the necessity of preventative measures, such as lifestyle adjustments, screening for risk factors, and drug treatments. In the future, the BOA-RC2 may be of interest to identify patients at high risk of mortality and ischaemic events for clinical research on new therapeutic options.

Platelet-reactivity tests identify patients at risk of secondary cardiovascular events: a systematic review and meta-analysis.

BACKGROUND: Antiplatelet therapy is the standard treatment for the prevention of cardiovascular events (CVEs). High on-treatment platelet reactivity (HPR) is a risk factor for secondary CVEs in patients prescribed aspirin and/or clopidogrel. The present review and meta-analysis was aimed at assessing the ability of individual platelet-function tests to reliably identify patients at risk of developing secondary CVEs. METHODS AND RESULTS: A systematic literature search was conducted to identify studies on platelet-reactivity measurements and CVEs. The main inclusion criteria were: (i) prospective study design; (ii) study medication, including aspirin and/or clopidogrel; and (iii) a platelet-function test being performed at baseline, before follow-up started. Of 3882 identified studies, 102 (2.6%; reporting on 44 098 patients) were included in the meta-analysis. With regard to high on-aspirin platelet reactivity (HAPR), 22 different tests were discussed in 55 studies (22 441 patients). Pooled analysis showed that HAPR was diagnosed in 22.2% of patients, and was associated with an increased CVE risk (relative risk [RR] 2.09; 95% confidence interval [CI] 1.77-2.47). Eleven HAPR tests independently showed a significantly increased CVE risk in patients with HAPR as compared with those with normal on-aspirin platelet reactivity. As regards high on-clopidogrel platelet reactivity (HCPR), 59 studies (34 776 patients) discussed 15 different tests, and reported that HCPR was present in 40.4% of patients and was associated with an increased CVE risk (RR 2.80; 95% CI 2.40-3.27). Ten tests showed a significantly increased CVE risk. CONCLUSIONS: Patients with HPR are suboptimally protected against future cardiovascular complications. Furthermore, not all of the numerous platelet tests proved to be able to identify patients at increased cardiovascular risk.

Young women with PAD are at high risk of cardiovascular complications.

OBJECTIVES: Prognostic research in patients with peripheral arterial disease (PAD) is scarce and determinants of outcome are mainly studied in males. The current management of PAD in women is based on evidence from, at best, mixed populations. We therefore assessed risk and prognostic factors in 313 men and 169 women from the Dutch Bypass Oral anticoagulants or Aspirin Study of whom long-term follow-up data were available. METHOD: The primary composite outcome event was vascular death, myocardial infarction, stroke, or major amputation during 5 years of follow-up. Variables with a p-value <0.2 in the univariate analyses were added to the multivariate Cox proportional hazards model. RESULTS: Females were older (71 vs. 68 years; p < 0.01), had more advanced PAD (critical limb ischemia (CLI) 52.1 vs. 42.2%; p = 0.04), more often had peripheral bypass surgery as primary intervention (50.5 vs. 32.5%; p < 0.01), and had more often hypertension (48.5 vs. 33.2%; p < 0.01) than males. Males were more often smokers (63.6 vs. 53.3%; p = 0.03) and had more prior myocardial infarctions (18.5 vs. 10.1%; p = 0.02). In total 170 events occurred, 74 (44%) in females and 96 (31%) in males. Overall, independent risk factors for the primary outcome event were age and critical limb ischemia. Independent risk factors in males were: age (HR: 1.06, 95% CI: 1.03-1.09), critical limb ischemia (HR: 1.7, 95% CI: 1.05-2.7), and diabetes mellitus (HR: 1.7, 95% CI: 1.01-2.8) and in females critical limb ischemia (HR: 3.5, 95% CI: 2.0-6.1), ABI≤0.9 (HR: 2.8, 95% CI: 1.2-6.1), and femorocrural bypass (HR: 1.9, 95% CI: 1.1-3.3). Although sex was not an independent risk factor in the overall analysis, women younger than 60 years had an increased risk for cardiovascular events compared to men of that age (HR: 4.9, 95% CI: 1.8-13.6), whereas no difference was seen above 60 years of age. CONCLUSIONS: Risk factors for cardiovascular events in patients with PAD differ between men and women. To our knowledge, this is the first study that shows such a bad outcome in female patients younger than 60 years of age. More awareness leading to early diagnosis and optimal treatment might improve long-term clinical outcome in (young) women with PAD.

Longer time interval between carotid cross-clamping and shunting is associated with increased 30-day stroke and death rate.

BACKGROUND: The benefit of carotid endarterectomy (CEA) in patients with a significant (>70%) (a)symptomatic stenosis has been proven thoroughly in major trials. It is unknown whether, after cross-clamping the carotid artery, the time interval between determination that a shunt is needed and the actual functioning of the shunt, defined as the need for shunt-to-shunt time (NST), influences 30-day morbidity and mortality rate after CEA. METHODS: Experienced vascular surgeons performed 851 CEAs with a selective shunting protocol based on perioperative transcranial Doppler measurement and electroencephalographic findings, and data were analyzed retrospectively. The study included 156 shunted patients. RESULTS: Longer NST was associated with an increase in the 30-day stroke/death rate. A binary logistic regression model was used to determine a 2-tailed P value of .004 and an odds ratio of 1.5/min increase of the NST. There was no influence on stroke-death rate of gender, age, symptomatic or asymptomatic stenosis, the use of a patch or not, or the number of periprocedural microembolic signals. CONCLUSION: If CEA is performed with a selective shunting protocol, a longer NST increases the 30-day stroke/death rate. These results support a strong recommendation that shunt placement should be as quick as possible.