Impact of Ankle Brachial Index Calculations on Peripheral Arterial Disease Prevalence and as a Predictor of Cardiovascular Risk.

OBJECTIVE: The aim of this study was to estimate the prevalence and predictive accuracy for cardiovascular (CV) morbidity by using different ankle brachial index (ABI) calculation methods in the general population. METHODS: ABI measurements and questionnaire data were collected from 5 080 randomly selected citizens aged 60 - 90 years. A 10 year follow up with data from Swedish national health registries was carried out. ABI was calculated using as numerator the highest (ABI-HI) or the lowest (ABI-LO) ankle BP obtained in each leg. Subjects were defined as references or having peripheral arterial disease (PAD) based on ABI-LO (Group 1) or ABI-HI (Group 2). Prevalence, mortality, CV events and risk were then analysed for these three groups, and their predictive power by using the area under the curve (AUC). RESULTS: A total of 4 909 inhabitants were included in the cohort (References: 83.8%, Group 1: 6.7% and Group 2: 9.6%). The prevalence of PAD was 16% using ABI-LO, and 9.6% using ABI-HI. The 10 year all cause mortality for references and Groups 1 and 2 was 27.6%, 48.8%, and 67.2%, respectively. The overall age adjusted hazard ratio (95% confidence interval) for the composite outcome of CV mortality and a non-fatal CV event was 1.25 (1.06 - 1.49) for Group 1 and 2.11 (1.85 - 2.39) for Group 2. The prediction accuracy for ABI < 0.9 in predicting CV event measured with AUC was 0.60 for ABI-HI and 0.62 for ABI-LO. CONCLUSION: An ABI < 0.9 should be considered a strong risk marker for future CV morbidity. Applying the traditional ABI calculation method of using the highest measured ankle BP, a group of subjects with high CV risk may be overlooked for intervention, and this why the lowest ankle BP should be the preferred for risk stratification. However, as a single predictive tool an ABI < 0.9 cannot adequately discriminate which individual will have a future CV event regardless of calculation method used.

Ten Year Mortality in Different Peripheral Arterial Disease Stages: A Population Based Observational Study on Outcome.

OBJECTIVE: The aim was to determine long-term mortality rates and the underlying cause of death for subjects with different peripheral arterial disease (PAD) stages in a population based setting. METHODS: A randomly selected population sample of 5080 subjects was enrolled in the study in 2004-2005. Participants completed health state questionnaires and underwent ankle brachial index (ABI) measurements for classification into PAD severity stages and reference subjects. A follow-up was conducted by the end of 2015 using data from Swedish governmental national registers for cause of death, which was then compared with PAD stage determined at baseline in 2005. RESULTS: The 10 year all cause mortality was 27% for reference cases, 56% for asymptomatic PAD (APAD), 63% for intermittent claudication (IC), and 75% for severe limb ischaemia (SLI). Among all PAD subjects, cardiovascular (CV) causes were the most common main cause of death (45%) and a CV event was present as either the main or one of the three most common contributing causes of death in 64% of the cases. The age adjusted hazard ratios for a main cause of death by a CV event were 1.9 (95% CI 1.5-2.3) for APAD, 2.6 (95% CI 2.1-3.4) for IC, and 3.5 (95% CI 2.3-5.2) for SLI. CONCLUSION: PAD subjects, including the APAD subjects, are still at high risk of CV death. The mortality risks are more than doubled in symptomatic PAD patients compared with reference subjects and increase by severity of PAD stage. Awareness and improved risk reduction management of PAD are still warranted.

The role of procalcitonin in postimplantation syndrome after EVAR: a pilot study.

BACKGROUND: After endovascular aortic repair (EVAR) for treatment of aortoiliac aneurysms, patients commonly develop an inflammatory reaction: Postimplantation syndrome (PIS). Clinically, it may be hard to separate PIS from an infectious complication. Procalcitonin (PCT) is a diagnostic marker for severe bacterial infections and sepsis. We hypothesize that low-PCT levels facilitate the PIS diagnosis after EVAR. METHODS: Sixty-nine elective EVAR patients were included. Tympanic temperature, C-reactive protein (CRP), white blood cell count (WBC), and PCT were measured on days -1 and +1, +3 and +5. Complications, in-hospital stay, and infections were recorded. PIS was defined by a body temperature of ≥38°C and WBC ≥12,000/µL combined with no other detected complication or surgical event explaining the inflammatory response. Three cohort subgroups were compared: the noncomplication group, those with PIS, and the patients with complications or additional open surgical events. RESULTS: All patients developed various extents of postoperative inflammatory responses including a rise in WBC, CRP, and/or temperature. PIS was diagnosed in 12 patients. Forty patients had no complication and seventeen suffered complications or had an additional open surgical event. All PIS patients showed low-PCT levels. On day +3, in the PIS group, median PCT was 0.22 ng/mL (95% confidence interval [CI]: 0.15-0.28), WBC 13.2 × 10(9)/L (11.4-15.6), and CRP 196 mg/L (149-243). High PCT was observed in 6 patients, out of which 4 had complications or additional open surgical procedures. CONCLUSIONS: In patients with PIS after EVAR, there was a strong inflammatory reaction. In the PIS condition, PCT remains low. This pilot study shows that PCT may be useful for the PIS diagnosis.

Presence of asymptomatic Peripheral Arterial Disease in combination with common risk factors elevates the cardiovascular risk Substantially.

Background and aims: This study evaluates the risks for adverse cardiovascular (CV) events in Asymptomatic Peripheral Arterial Disease (APAD) combined with different traditional CV risk factors. Methods: A population-based observational study of 8000 subjects, identified 559 subjects as having APAD through ankle-brachial index (ABI) measurements and questionnaires regarding limb symptoms. This cohort and subgroups classified by presence of different traditional CV risk factors at baseline were assessed for 10 years on CV outcome. The recorded endpoints were all-cause mortality, CV mortality and non-fatal CV events. Results: Before subdividing the APAD subjects, the CV mortality incidence was 28.5 deaths per 1000 person-years as compared to 8.7 deaths for references without APAD. For subjects with hypertension at baseline the CV mortality incidence was 35.4 when combined with APAD and 11.7 without. In women with hypertension but without other risk factors, presence of APAD increased the age-adjusted Hazard Ratio (HR) for fatal and non-fatal CV events by 1.86 [CI 1.54,2.24, p < 0.001]. Conclusions: ABI measurements should be considered an important indication for aggressive multifactorial risk factor reduction in populations with any other prevalent CV risk factor. In hypertension, diabetes mellitus and a smoking history, coexisting APAD contributes significantly to the increased age-adjusted CV risk.

Cardiovascular long-term outcome and prophylactic treatment patterns in peripheral arterial disease in a population-based cohort.

AIMS: This study evaluates 10-year follow-up data on associated comorbidity, mortality, and pharmacological treatment patterns for men and women with different stages of peripheral arterial disease (PAD) in a population-based setting. METHODS AND RESULTS: This was a prospective observational population-based cohort study, based on physical examinations and questionnaires at baseline supplemented with national register data between 2005 and 2015. Subjects were placed in subgroups defined by ankle-brachial index levels and reported symptoms; asymptomatic PAD (APAD), intermittent claudication (IC), severe limb ischaemia (SLI), or references (Ref). Cox proportional hazards regression models were used for analysis with adjustments for sex and baseline age and comorbidity. The cohort consisted of 5080 subjects (45% males). At baseline, APAD, IC, and SLI were prevalent in 559 (11%), 320 (6.3%), and 78 (1.5%) subjects, respectively. A significant increased risk for cardiovascular (CV) death, even when adjusted for age and baseline morbidity, were noted in all PAD stages as compared with reference group with a small difference between APAD and IC, an adjusted hazard ratio 1.80 (confidence interval 1.45-2.22) and 1.95 (1.50-2.53), respectively. Only about 60% of PAD subjects received medical prophylactic treatment as recommended in guidelines. CONCLUSION: Peripheral arterial disease subjects had significantly increased CV morbidity and mortality risks, especially males. Asymptomatic PAD subjects confer similar risk for CV events as symptomatic patients. Our findings motivate enhanced preventive efforts of all PAD stages, including in asymptomatic disease.

The Impact of Stent Graft Material on the Inflammatory Response After EVAR.

BACKGROUND: Patients undergoing endovascular aneurysm repair (EVAR) due to abdominal aortic aneurysm often develop an inflammatory response, postimplantation syndrome (PIS) where fever and leukocytosis are common. Previous studies suggest that type of stent graft material (polyester or polytetrafluoroethylene [PTFE]) plays a role. OBJECTIVES: To investigate the effect of stent graft material on the inflammatory response and length of hospital stay in patients undergoing standard elective EVAR. METHODS: Sixty-nine elective EVAR patients were included in this observational study. To avoid comparing patients with a different graft location and stent graft burden, 12 cases were excluded as well as cases with complication or simultaneous open surgical procedures, leaving 45 patients (32 with polyester and 13 with PTFE graft) for final analysis. Tympanic temperature, C-reactive protein (CRP), white blood cell (WBC), and procalcitonin (PCT) were measured on days -1 and +1 and +3. Duration of in-hospital stay and frequency of PIS were recorded. RESULTS: The PIS was diagnosed in 9 (28.1%) of the 32 polyester cases and in 1 (7.7%) of the 13 cases in the PTFE group (P = .24). Median (interquartile range) in-hospital stay was 5 (5-6) days in the polyester group and 4 (4-5) days in the PTFE group (P = .009). On day +3, in the polyester group, mean CRP was 154 (95% confidence interval: 127-182) mg/L, WBC 9.5 (8.4-10.5) ×10(9)/L, and PCT 0.17 (0.12-0.21) ng/mL. In the PTFE group, mean CRP was 70 (32-109) mg/L (P = .001), WBC 8.8 (6.4-11.1) ×10(9)/L (P = .37), and PCT 0.09 (0.06-0.13) ng/mL (P = .009) on day +3. CONCLUSION: Standard EVAR with polyester stent grafts appears to result in a trend toward a more pronounced inflammatory reaction than similar EVAR using PTFE and is associated with a longer in-hospital stay.