2011 ACCF/AHA focused update of the guideline for the management of patients with peripheral artery disease (updating the 2005 guideline)

Predictive value of plasma ephrinB2 levels for amputation risk following endovascular revascularization in peripheral artery disease

Background

The aim of this study is to investigate the expression levels of ephrinB2 in patients with lower extremity peripheral arterial disease (PAD) and explore its association with the severity of the disease and the risk of amputation after endovascular revascularization.

Methods

During the period from March 2021 to March 2023, this study collected blood samples and clinical data from 133 patients diagnosed with lower extremity PAD and 51 healthy volunteer donors. The severity of lower extremity PAD patients was classified using the Rutherford categories. The expression of ephrin-B2 in plasma samples was detected using the Western Blotting.

Results

Compared to the control group, the levels of serum ephrinB2 in patients were significantly elevated (p < 0.001). Moreover, the plasma EphrinB2 levels were positively correlated with white blood cell counts (r = 0.204, p = 0.018), neutrophil counts (r = 0.174, p = 0.045), and neutrophil-to-lymphocyte ratio (NLR) (r = 0.223, p = 0.009). Furthermore, the AUCs of plasma ephrinB2 level, NLR, and their combination as predictors for amputation events within 30 months after lower extremity PAD endovascular revascularization were 0.659, 0.730 and 0.811. In the high-ephrinB2 group, the incidence of amputation events within 30 months after endovascular revascularization was higher.

Conclusions

Plasma EphrinB2 levels may be linked to lower extremity PAD development, inflammation, and postoperative amputation. Combining EphrinB2 and NLR can improve amputation prediction accuracy after endovascular revascularization in lower extremity PAD patients.

Comparative effectiveness of endovascular treatment modalities for de novo femoropopliteal lesions at long-term follow-up: A network meta-analysis of randomized controlled trials

PURPOSE

To evaluate the best endovascular treatment for de novo femoropopliteal lesions at long-term follow-up through network meta-analysis of randomized controlled trials.

METHODS

Medical databases were searched on September 17, 2023. 17 trials and 7 treatments were selected. Outcomes were primary patency, target lesion revascularization (TLR), major amputation and all-cause mortality at 3 and/or 5 years.

RESULTS

Regarding 3-year primary patency, drug-eluting stents (DES) was the best and better than balloon angioplasty (BA; odds ratio [OR], 4.96; 95% confidence interval [CI], 2.68-9.18), bare metal stents (BMS; OR, 2.81; 95% CI, 1.45-5.46), cryoplasty (OR, 6.75; 95% CI, 2.76-16.50), covered stents (CS; OR, 3.25; 95% CI, 1.19-8.87) and drug-coated balloons (DCB; OR, 2.04; 95% CI, 1.14-3.63). Regarding 5-year primary patency, DES was the best and better than BMS (OR, 2.34; 95% CI, 1.10-4.99). Regarding 3-year TLR, DES was the best and better than BA (OR, 0.24; 95% CI, 0.13-0.44). Regarding 5-year TLR, DES was the best and better than BA (OR, 0.20; 95% CI, 0.09-0.42) and balloon angioplasty with brachytherapy (OR, 0.21; 95% CI, 0.06-0.74). Regarding 3- and 5-year major amputation, DCB was the best. Regarding 3-year mortality, DES was the best and better than CS (OR, 0.09; 95% CI, 0.01-0.67).

CONCLUSIONS

DES was the best treatment regarding 3-year primary patency, TLR and mortality, and DCB was the best regarding major amputation. DES was the best treatment regarding 5-year TLR, and DCB was the best regarding primary patency and major amputation. DES and DCB should be given priority in treating femoropopliteal lesions.

Treatment of Aortic and Iliac Artery Occlusion by Catheter Thrombolysis Combined with Catheter Thrombectomy and Aortic Bifurcation Endovascular Stent Reconstruction

Aortoiliac occlusive disease (AIOD) is an occlusive disease of the infrarenal aorta and iliac arteries usually caused by stenosis or occlusion at the end of the abdominal aorta-common iliac artery. Herein, we reported a case of Trans-Atlantic Inter-Society Consensus- (TASC-) D AIOD with pale, cool, and intangible dorsalis pedis artery treated with catheter thrombolysis combined with catheter thrombectomy and aortic bifurcation endovascular stent reconstruction, which proved to be safe, effective, and minimally invasive approach. In the present paper, we discussed the physical and imaging manifestations, as well as treatments.

End-stage renal disease patients undergoing angioplasty and bypass for critical limb ischemia have worse outcomes compared to non-ESRD patients: Systematic review and meta-analysis

BACKGROUND

End-stage renal disease (ESRD) is associated with increased morbidity and mortality following lower extremity amputation for critical limb ischemia (CLI). Angioplasty and bypass are used in ESRD patients with CLI; however, the treatment of choice remains controversial. We compared the long-term outcomes in patients with CLI undergoing angioplasty or bypass to evaluate the differences between patients with ESRD and those without ESRD.

METHODS

Established databases were searched for observational studies comparing outcomes following bypass or angioplasty for CLI in patients with ESRD to those in non-ESRD patients. End points included survival, limb salvage, amputation-free survival (AFS), and primary and secondary patency at 1-year post-procedure. Pooled odds ratios (OR) with 95% confidence intervals (CI) were calculated using a random effect model.

RESULTS

We included 20 studies with a total of 24,851 patients. ESRD patients compared to non-ESRD patients with CLI had significantly lower survival post-angioplasty (OR 0.51, 95% CI 0.36-0.72, p < .001) and post-bypass (OR 0.26, 95% CI 0.15-0.45, p < .001). ESRD patients had lower rates of limb salvage post-bypass (OR 0.33, 95% CI 0.21-0.53, p < .001) and post-angioplasty (OR 0.54, 95% CI 0.41-0.70, p < .001). AFS was significantly lower in ESRD patients compared to non-ESRD patients following angioplasty (OR 0.48, 95% CI 0.32-0.71, p < .001) and bypass (OR 0.28, 95% CI 0.16-0.47, p < .001) despite no significant differences in primary patency. ESRD patients had overall worse secondary patency post-angioplasty and/or bypass (OR 0.54, 95% CI 0.32-0.94, p = .03) compared to non-ESRD patients. A meta-analysis of four studies directly comparing survival in ESRD patients with CLI based on whether they underwent angioplasty or bypass showed no difference (OR 0.93, 95% CI 0.64-1.35, p = .69).

CONCLUSION

ESRD patients have worse survival, limb salvage, and AFS outcomes following angioplasty and bypass for CLI compared to non-ESRD patients. Large randomized controlled trials comparing these two modalities of treatment in this patient population are needed for further clarity.

The effect of lifestyle and risk factor modification on occlusive peripheral arterial disease outcomes: standard healthcare vs structured programme-for a randomised controlled trial protocol

Background

Peripheral arterial disease (PAD) affects more than 200 million of the global population. PAD represents a marker for premature cardiovascular events. Patients with PAD, even in the absence of a history of myocardial infarction or ischemic stroke, have approximately the same relative risk of death from cardiovascular causes as patients with a history of coronary or cerebrovascular disease. Despite the high prevalence of PAD and the strong association with cardiovascular morbidity and mortality, patients with PAD are less likely to receive appropriate treatment for their atherosclerotic risk factors than those who are being treated for coronary artery disease.

Atherosclerotic risk factor identification and modification play an important role in reducing the number of adverse outcomes among patients with atherosclerosis. Risk reduction therapy decreases the risk of cardiovascular mortality and morbidity in patients with PAD. In this study, we aim to evaluate the effectiveness of a lifestyle and risk factor modification intervention programme in achieving treatment goals for PAD risk factors.

Methods

This is a randomised, parallel group, active-control trial to compare the effectiveness of the risk factor modification intervention programme to standard healthcare in a tertiary vascular care centre, in the reduction of modified risk factors in PAD patients. The primary outcome of this study is to evaluate the effectiveness of a lifestyle and risk factor modification intervention programme in achieving treatment goals for PAD risk factors at 3 and 12 months. The secondary outcomes are to compare the impact of the programme on clinical outcomes in PAD patients at 12 months. Secondary outcomes include amputation-free survival, clinical improvement, haemodynamic improvement, need for revascularisation procedures, outcomes of revascularisation procedures, changes in quality of life and the incidence of adverse events.

Discussion

This study will provide clear evidence on the effectiveness of a lifestyle and risk factor modification intervention programme in achieving treatment goals for PAD risk factors, through a high-quality, well-powered clinical trial.

Trial registration

This trial was registered (11/07/2017) on the European Clinical Trials Database (EudraCT number 2017-002964-41) and ClinicalTrials.gov (NCT03935776) which was registered on 02 May 2019.

Supplementary Information

The online version contains supplementary material available at 10.1186/s13063-021-05087-x.

Platelet aggregation inhibitor prescription for newly diagnosed peripheral arterial disease in the Netherlands: a cohort study

OBJECTIVES

Pharmacological treatment of peripheral arterial disease (PAD) comprises of antiplatelet therapy (APT), blood pressure control and cholesterol optimisation. Guidelines provide class-I recommendations on the prescription, but there are little data on the actual prescription practices. Our study provides insight into the prescription of medication among patients with PAD in the Netherlands and reports a 'real-world' patient journey through primary and secondary care.

DESIGN

We conducted a cohort study among patients newly diagnosed with PAD between 2010 and 2014.

SETTING

Data were obtained from the PHARMO Database Network, a population-based network of electronic pharmacy, primary and secondary healthcare setting records in the Netherlands. The source population for this study comprised almost 1 million individuals.

PARTICIPANTS

'Newly diagnosed' was defined as a recorded International Classification of Primary Care code for PAD, a PAD-specific WCIA examination code or a diagnosis recorded as free text episode in the general practitioner records with no previous PAD diagnosis record and no prescription of P2Y12 inhibitors or aspirin the preceding year. The patient journey was defined by at least 1 year of database history and follow-up relative to the index date.

RESULTS

Between 2010 and 2014, we identified 3677 newly diagnosed patients with PAD. Most patients (91%) were diagnosed in primary care. Almost half of all patients (49%) had no APT dispensing record. Within this group, 33% received other anticoagulant therapy (vitamin K antagonist or direct oral anticoagulant). Mono-APT was dispensed as aspirin (40% of patients) or P2Y12 inhibitors (2.5% of patients). Dual APT combining aspirin with a P2Y12 inhibitor was dispensed to 8.5% of the study population.

CONCLUSION

Half of all patients with newly diagnosed PAD are not treated conforming to (international) guideline recommendations on thromboembolism prevention through APT. At least 33% of all patients with newly diagnosed PAD do not receive any antithrombotic therapy. Evaluation and improvement of APT prescription and thereby improved prevention of (secondary) cardiovascular events is warranted.

Patterns of urinary albumin and IgM associate with markers of vascular ageing in young to middle-aged individuals in the Malmö offspring study

BACKGROUND

Increased urinary excretion of IgM and low-grade albuminuria are associated with increased risk of cardiovascular morbidity and mortality. The objective of this study was to investigate the association between urinary IgM, albuminuria, and vascular parameters reflecting arterial structure and function.

METHODS

Subjects of the present study were from the Malmö Offspring study (MOS) cohort, and included 1531 offspring (children and grand-children) to first-generation subjects that participated in the Malmö Diet Cancer-Cardiovascular Arm study cohort. At baseline, technical measurements of arterial stiffness (carotid-femoral pulse wave velocity; c-f PWV), carotid arterial morphology, 24-h ambulatory blood pressure recordings, ankle-brachial-index (ABI), and evaluation of endothelial function (reactive hyperemia index, RHI) were performed. Urinary (U) IgM, U-albumin, and U-creatinine were measured. Multivariate adjusted logistic regression was used to test whether U-IgM excretion and increasing urinary albumin excretion were related to vascular parameters.

RESULTS

Detectable U-IgM was independently associated with higher systolic blood pressure, odds ratio (OR) 1.021, 95% confidence interval (CI, 1.003-1.039), p = 0.025 and lower ABI; ABI dx: OR 0.026, 95% CI (0.002-0.381), p = 0.008, ABI sin: OR 0.040, 95% CI (0.003-0.496), p = 0.012. Low-grade albuminuria was independently associated with systolic and diastolic blood pressure, aortic blood pressure, the c-f PWV and the number of carotid intima plaques (p < 0.05).

CONCLUSIONS

In young to middle-aged, mostly healthy individuals, increased U-IgM excretion and low-grade albuminuria are associated with adverse vascular parameters. Increased U-IgM excretion may reflect subclinical peripheral atherosclerosis, whereas increased U-albumin excretion is associated with a wide range of cardiovascular abnormalities. This may reflect different pathophysiological mechanisms.

Comparative Effectiveness of Endovascular Treatment Modalities for De Novo Femoropopliteal Lesions: A Network Meta-analysis of Randomized Controlled Trials

Purpose: To report the results of a network meta-analysis of randomized controlled trials (RCTs) comparing multiple endovascular treatments for de novo femoropopliteal lesions. Materials and Methods: The MEDLINE, EMBASE, and the Cochrane Central Register of Controlled Trials databases were systematically searched on June 1, 2019, for prospective RCTs comparing 14 treatments [ie, atherectomy, brachytherapy, cryoplasty, cutting balloons, drug-coated balloons, bare nitinol stents, drug-eluting stents (DES), covered stents (CS), and combinations] in the treatment of de novo femoropopliteal lesions. Outcomes were technical success; binary restenosis and target lesion revascularization (TLR) at 6, 12, and/or 24 months; and all-cause mortality at 12 months. Ultimately, 53 articles reporting on 45 studies (91 study arms; 5565 patients) were selected. For the technical success outcome, all types of stents, all balloons, and all atherectomy devices were aggregated in stent, balloon, and atherectomy technology groups, respectively. Results: In terms of technical success for aggregated treatment types, stent technology was the most effective treatment and was better than balloon and atherectomy technologies. In terms of binary restenosis, DES was the most effective single treatment at the 6- and 12-month follow-up and CS at the 24-month follow-up. Both DES and CS were better than the majority of other single treatments, including balloon angioplasty, cutting balloon, cryoplasty, directional atherectomy, and bare nitinol stent during all follow-up periods. In terms of TLR, DES was the second most effective single treatment and the most effective single treatment at the 6- and 12-month follow-up intervals; CS was the most effective single treatment at the 24-month follow-up. Both DES and CS were better than the majority of other single treatments. The 12-month all-cause mortality of both DES and CS were similar to other treatments, whereas cryoplasty seemed to be the least effective treatment with regard to binary restenosis and TLR. Conclusion: Both DES and CS had substantial advantages in terms of restenosis and TLR in femoropopliteal lesions and were similar to aggregate stent technology in terms of technical success. DES performed better within 12 months after operation and CS at ~24 months, but neither had much advantage in terms of mortality. In contrast, cryoplasty seemed to be a less effective treatment.

Association between Preoperative Indications and Outcomes after Major Lower Extremity Amputation

Despite aggressive limb salvage techniques, lower extremity amputation (LEA) is frequently performed. Major indications for LEA include ischemia and uncontrolled infection (UI). A review of the national Vascular Quality Initiative amputation registry was performed to analyze the influence of indication on outcomes after LEA. Retrospective review of the Vascular Quality Initiative LEA registry (2012–2017) identified all above- and below-knee amputations. Outcome measures included 30-day mortality, return to operating room (OR), postoperative myocardial infarctions, and postoperative SSI. Indications for surgery included ischemic rest pain, ischemic tissue loss (TL), acute limb ischemia (ALI), UI, and neuropathic TL. A total of 6701 patients met the inclusion criteria. The indications for surgery included TL (49.0%), UI (31.7%), ALI (8.0%), rest pain (6.6%), and neuropathic TL (2.3%). Patients with ALI had the highest 30-day mortality (12.0%) compared with TL (6.6%) and UI (6.4%) [ P < 0.001]. The highest rate of return to OR occurred in the UI group (12.6%) [ P < 0.001]. Multivariate analysis demonstrated that patients with UI have significantly higher rates of return to OR, whereas those with ALI have a 30-day mortality twice as high as other indications (both P < 0.001). These data can inform expectations after LEA based on the indications for surgery.

Ankle-brachial index and peripheral arterial disease: An evaluation including a type 2 diabetes mellitus drug-naïve patients cohort

BACKGROUND

Peripheral arterial disease in patients with type 2 diabetes mellitus is an important risk factor for vascular events. Recommendations about whether ankle-brachial index should be performed differ depending on the source; therefore, it is necessary to re-evaluate the most important risk factors associated with peripheral arterial disease and whether it is useful to perform ankle-brachial index in newly diagnosed and drug-naïve patients with diabetes, independent of age or peripheral arterial disease symptoms.

METHODS

A total of 711 subjects were divided into groups: group 1, 600 type 2 diabetes mellitus patients, symptomatic or not for peripheral arterial disease; group 2, 61 type 2 diabetes mellitus patients newly diagnosed and drug naïve; and group 3, 50 subjects without diabetes. Ankle-brachial index, medical records and physical examination were performed in all patients, accessing cardiovascular risk factors.

RESULTS

Analysing group 1 asymptomatic patient to peripheral arterial disease, we found abnormal ankle-brachial index in 49% (77/156) ⩾50 years and 42% (16/38) <50 years (p = not significant). Considering drug-naïve patients, a peripheral arterial disease prevalence of 39% (24/61) was found; among these, 48% (13/27) were <50 years and 32% (11/34) were ⩾50 years (p = not significant). A forward stepwise regression model was developed, with type 2 diabetes mellitus duration (r² = 0.12) and sedentary lifestyle (r² = 0.14) found as independent variable predictors of severity of peripheral arterial disease, related to ankle-brachial index.

CONCLUSION

We suggest that, in type 2 diabetes mellitus, ankle-brachial index should be measured at diagnosis. In addition, sedentary lifestyle was strongly associated with presence and severity of peripheral arterial disease.

The peripheral atherosclerotic profile in patients with type 1 diabetes warrants a thorough vascular assessment of asymptomatic patients

AIMS

Epidemiological data on subclinical atherosclerotic disease in type 1 diabetes mellitus (DM1) are scarce. We aimed to estimate the subclinical atherosclerosis profile of asymptomatic patients with DM1 and an abnormal ankle-brachial index (ABI).

MATERIAL AND METHODS

In a cross-sectional design (ClinicalTrials.gov Identifier: NCT02910271), we estimated ABI in 289 consecutive asymptomatic patients with DM1. An abnormal ABI led to measurements of toe-brachial index (TBI) and peripheral doppler ultrasound (DUS) to diagnose peripheral artery disease (PAD) and/or atherosclerotic carotid plaques (ACP).

RESULTS

A reduced (≤0.9) or increased (>1.2) ABI was detected in 17 (6%) and 75 (26%) patients, respectively. PAD was confirmed by TBI and DUS in 9 (53%) patients with a reduced ABI and 28 (37%) patients with an increased ABI, resulting in a 12.8% (9.4-17.2) prevalence of asymptomatic PAD. Fourteen patients with an abnormal ABI also exhibited ACP [4.8% (2.9-7.9)], with 64% of these patients showing bilateral disease. Artery stenosis was mild or moderate in 21% and 29% of patients, respectively. Thus, 46 [16% (12-21)] patients showed asymptomatic PAD, ACP, or both. According to our data, we would have to explore three asymptomatic patients with DM1 and normal pulses to unmask one case of PAD, and seven asymptomatic patients showing abnormal ABI values to detect one carotid disease.

CONCLUSIONS

Peripheral artery disease is often undiagnosed in asymptomatic patients with DM1. However, its presence may change medical management in a substantial percentage of cases, highlighting the potential benefit of a thorough vascular assessment on these patients.

The intrinsic prognostic value of the ankle-brachial index is independent from its mode of calculation

The object of this study was to compare the prognostic value of different methods of ankle-brachial index (ABI) calculation. From April 1998 to September 2008, we calculated the ABI in 1223 patients before coronary artery bypass grafting. The ABI was calculated according to five different calculation modes of the numerator. The patients were classified into three groups: clinical peripheral artery disease (PAD), subclinical PAD if no clinical history but abnormal ABI (< 0.90 or > 1.40), and no PAD. The primary outcome was total mortality. During a follow-up of 7.6 years (0.1-15.9), 406 patients (33%) died. The prevalence of the subclinical PAD varied from 22% to 29% according to the different modes of ABI calculation. Areas under the ROC curve to predict mortality according to different calculation modes varied from 0.608 ± 0.020 to 0.625 ± 0.020 without significant differences. The optimal ABI threshold to predict mortality varied for every method, ranging from 0.87 to 0.95. In multivariate models, ABI was significantly and independently associated with total mortality (hazard ratio (HR) = 1.46, 95% CI: 1.15-1.85, p = 0.002); however, this association was not significantly different between the various methods (HRs varying from 1.46 to 1.67). The use of the optimal ABI threshold for each calculation mode (rather than standard 0.90) allowed a slight improvement of the model. In conclusion, the ABI prognostic value to predict mortality is independent from its method of calculation. The use of different optimal thresholds for each method enables a comparable prognosis value.

Physical examination to screen for peripheral artery disease in a defined Primary Care population: A diagnostic accuracy study

INTRODUCTION

Peripheral arterial disease (PAD) is an underdiagnosed prevalent disease which implies high cardiovascular risk. Professionals usually depend on physical examination to screen for PAD.

OBJECTIVE

To assess the diagnostic accuracy of physical examination to screen for PAD in a rural Primary Care population and to evaluate the nurse-physician level of agreement in pedal pulse palpation.

METHODS

Diagnostic accuracy study in which two experienced professionals (physician-nurse) prospectively performed pedal pulse palpation (grading as absent, reduced, normal, or bounding), femoral bruit auscultation and calf circumference (index tests) comparing with Doppler ABI (reference test, positive cut-off: 0.9 ≥ ABI ≥ 1.4) in 158 consecutive subjects.

INCLUSION CRITERIA

presence of diabetes, dyslipidaemia, hypertension, smoking habit (current or former), or age ≥ 65.

RESULTS

Of 315 legs included, PAD was confirmed in 38 (12.1%) legs. Absent dorsalis pedis (DP) and posterior tibial (PT) pulses were found in 37 (11.7%) and 67 (21.3%) legs, respectively. Regarding nurse evaluation, when a positive test was set if DP or PT were absent (more sensitive cut-off), sensitivity was = 86.8 (95% CI: 74.8-98.9), specificity = 82.7 (95% CI: 78.0-87.3), likelihood ratio+ = 5.01 (95% CI: 3.77-6.67), likelihood ratio- = 0.16 (95% CI: 0.07-0.36), and diagnostic odds ratio (dOR) = 31.5 (95% CI: 11.7-84.8). Age, diabetes, and calcification (ABI ≥ 1.4) influenced the rate of a false negative finding in pedal palpation. Physician-nurse weighted kappa coefficient was = 0.649 (95% CI: 0.599-0.699). The presence of a femoral bruit auscultation had a dOR = 3.8 (95% CI: 1.1-13.1), and a calf circumference <34.55 cm had a dOR = 3.2 (95% CI: 1.6-6.4).

CONCLUSIONS AND RELEVANCE

In a mainly asymptomatic Primary Care population, pedal pulse palpation was by far the best diagnostic test, with good diagnostic accuracy and inter-rater agreement. In view of a high sensitivity and capacity to rule out the disease, pedal pulse palpation could be performed as a screening test for PAD and individuals at high cardiovascular risk.

Carotid intima-media thickness and plagues are associated with indicators of peripheral artery diseases in patients with diabetes

AIMS

We investigated associations of carotid intima-media thickness (CIMT) and carotid plaque with ankle-brachial index (ABI) and toe-brachial index (TBI) in Chinese adults.

METHODS

A cross-sectional analysis was performed in 6688 participants from a well-defined Chinese community. CIMT and carotid plaque was measured with a high-resolution B-mode tomographic ultrasound system. Low ABI was defined as ABI ≤ 0.90. Low TBI was defined as TBI ≤ 0.60. Carotid plaques were classified as normal, homogeneous or heterogeneous according to morphology.

RESULTS

After adjusting for age, sex and body mass index, each 0.10 mm CIMT increase was associated with 0.0123 unit decrease in TBI (P = 0.004) and 0.0063 in ABI (P = 0.04) in patients with diabetes. After further adjustments for waist circumference, smoking and drinking habits, hypertension, lipids and hemoglobin A1c, the associations between CIMT and TBI remained significant; while those with ABI were disappeared. Meanwhile, each 0.10 mm increment of CIMT or rank of carotid plaque morphology was associated with a risk of presence of low TBI (CIMT: odds ratio: 1.21, 95% confidence interval: 1.05-1.40; carotid plaque morphology: 1.45, 1.01-2.08) in patients with diabetes after adjustments. However, no associations were found between CIMT or carotid plaque morphology and TBI or ABI in non-diabetic participants.

CONCLUSIONS

CIMT and carotid plaque morphology were significantly associated with TBI in patients with diabetes.

Spectrum effect and spectrum bias in the oscillometric ankle brachial index to diagnose peripheral arterial disease: Clinical implications

BACKGROUND AND AIMS

The diagnostic performance of the oscillometric ankle brachial index (ABI) to detect peripheral arterial disease (PAD) varies among populations, suggesting a spectrum effect. When this heterogeneity modifies post-test probabilities, a spectrum bias arises. This study evaluates the presence and influence of spectrum effect and spectrum bias on test performance and clinical decisions.

METHODS

Oscillometric and Doppler ABI were compared in two settings: Primary-Care (333 legs) and Vascular-Service (41 legs). Spectrum effect was assessed using stratification and logistic regression, while spectrum bias was assessed through graphical and statistical tests based on predictive values and likelihood ratios, respectively.

RESULTS

Across subgroups, sensitivity ranged from 61.5% to 90.9%, and specificity from 81.8% to 99.1%. Logistic regression confirmed a spectrum effect in setting, diabetes, smoking status and age (univariate), and setting and diabetes (multivariate model). The positive likelihood ratio ranged from 5.0 to 89.1 in subgroups, leading to a spectrum bias in diabetic, smoking (both subgroups) and age (both subgroups). Therefore, a positive test ruled in differently the disease across subgroups, with a high rate of false positives in diabetic, smoking and >75-year-old patients. The negative likelihood ratio ranged from 0.09 to 0.39 in subgroups, with significant spectrum bias in Primary-Care patients, non-diabetics and smokers. Thus, in these subgroups, a negative test ruled out the disease with less certainty.

CONCLUSIONS

Spectrum effect and spectrum bias were found in oscillometric ABI to detect PAD, potentially affecting clinical decisions, especially for positive tests. Information about spectrum variables and the application of specific subgroups indicators are necessary.

Effects of acute exercise on endothelial function in patients with abdominal aortic aneurysm

Endothelial dysfunction is observed in patients with abdominal aortic aneurysm (AAA), who have increased risk of cardiovascular events and mortality. This study aimed to assess the acute effects of moderate- and higher-intensity exercise on endothelial function, as assessed by flow-mediated dilation (FMD), in AAA patients (74 ± 6 yr old, n = 22) and healthy adults (72 ± 5 yr old, n = 22). Participants undertook three randomized visits, including moderate-intensity continuous exercise [40% peak power output (PPO)], higher-intensity interval exercise (70% PPO), and a no-exercise control. Brachial artery FMD was assessed at baseline and at 10 and 60 min after each condition. Baseline FMD was lower [by 1.10% (95% confidence interval: 0.72-.81), P = 0.044] in AAA patients than in healthy adults. There were no group differences in FMD responses after each condition ( P = 0.397). FMD did not change after no-exercise control but increased by 1.21% (95% confidence interval: 0.69-1.73, P < 0.001) 10 min after moderate-intensity continuous exercise in both groups and returned to baseline after 60 min. Conversely, FMD decreased by 0.93% (95% confidence interval: 0.41-1.44, P < 0.001) 10 min after higher-intensity interval exercise in both groups and remained decreased after 60 min. We found that the acute response of endothelial function to exercise is intensity-dependent and similar between AAA patients and healthy adults. Our findings provide evidence that regular exercise may improve vascular function in AAA patients, as it does in healthy adults. Improved FMD after moderate-intensity exercise may provide short-term benefit. Whether the decrease in FMD after higher-intensity exercise represents an additional risk and/or a greater stimulus for vascular adaptation remains to be elucidated. NEW & NOTEWORTHY Abdominal aortic aneurysm patients have vascular dysfunction. We observed a short-term increase in vascular function after moderate-intensity exercise. Conversely, higher-intensity exercise induced a prolonged reduction in vascular function, which may be associated with both short-term increases in cardiovascular risk and signaling for longer-term vascular adaptation in abdominal aortic aneurysm patients.

Ankle-brachial Index for the Prognosis of Cardiovascular Disease in Patients with Mild Renal Insufficiency

Objective A low ankle-brachial index (ABI) is a known predictor for future cardiovascular events and mortality in patients with chronic kidney disease (CKD). While most prior studies have defined CKD as an estimated glomerular filtration rate (eGFR) <60 mL/min/1.73 m2, recent reports have suggested that the cardiovascular risk may be increased even in early stages of renal insufficiency. We hypothesized that a low ABI may predict future cardiovascular morbidity and mortality in patients with mild impairment of the renal function. Methods The IMPACT-ABI study was a retrospective, single-center, cohort study that enrolled and obtained ABI measurements for 3,131 patients hospitalized for cardiovascular disease between January 2005 and December 2012. From this cohort, we identified 1,500 patients with mild renal insufficiency (eGFR =60-89 mL/min/1.73 m2), and stratified them into 2 groups: ABI ≤0.9 (low ABI group; 9.2%) and ABI >0.9 (90.8%). The primary outcome measured was the cumulative incidence of major adverse cardiovascular events (MACE; cardiovascular death, myocardial infarction, and stroke). Results Over a mean follow-up of 5.0 years, 101 MACE occurred. The incidence of MACE was significantly higher in patients with low ABI than in those with ABI >0.9 (30.2% vs. 14.4%, log rank p<0.001). A low ABI was associated with MACE in a univariate Cox proportional hazard analysis. A low ABI remained an independent predictor of MACE in a multivariate analysis adjusted for cardiovascular risk factors (hazard ratio (HR): 2.27; 95% confidence interval (CI): 1.33-3.86; p=0.002). Conclusion Low ABI was an independent predictor for MACE in patients with mild renal insufficiency.

Increased risk of deep vein thrombosis and pulmonary thromboembolism in patients with aortic aneurysms: A nationwide cohort study

Studies on the association between aortic aneurysm (AA) and the subsequent risk of venous thromboembolism (VTE) are limited to a few case reports and investigations which only focused on surgical effects. Therefore, we used the National Health Insurance Research Database to clarify whether patients with AAs have a heightened risk of subsequent VTEs, including deep vein thrombosis (DVT) and pulmonary embolism (PE). Our retrospective cohort study comprised patients aged ≥ 18 years who received a diagnosis of an AA and were hospitalized at any point during 2000–2010 (n = 16,630). Each AA patient was frequency-matched to 4 non-AA hospitalized patients based on age, sex, and index year (n = 66,453). The Cox proportional hazard regressions model was used to estimate the adjusted effect of AAs on VTE risk. The overall incidence of DVT and PE was higher in the patients with AA than in the non-AA group patients (23.5 versus 13.2 and 13.5 versus 7.98/1,000 person-years). After adjustment for age, sex, duration of hospitalization in the study period, and comorbidities, patients with AAs were associated with a 1.88-fold higher risk of DVT and 1.90-fold higher risk of PE compared to the non-AA cohort. Patients with abdominal AAs were more likely to develop DVT, whereas thoracic AA patients were more likely to develop PE. A diagnosis of a ruptured AA was associated with a substantially increased risk of DVT. Surgical treatment of AAs was associated with a heightened risk of VTE within 6-months post-operation. Our study demonstrates that AAs are associated with an increased risk of subsequent VTE. Future investigations are encouraged to delineate the mechanisms underlying this association and to evaluate the cost-effectiveness of screening for VTEs in patients with AAs.

Disruption of mitochondrial quality control in peripheral artery disease: New therapeutic opportunities

Peripheral artery disease (PAD) is a multifactorial disease initially triggered by reduced blood supply to the lower extremities due to atherosclerotic obstructions. It is considered a major public health problem worldwide, affecting over 200 million people. Management of PAD includes smoking cessation, exercise, statin therapy, antiplatelet therapy, antihypertensive therapy and surgical intervention. Although these pharmacological and non-pharmacological interventions usually increases blood flow to the ischemic limb, morbidity and mortality associated with PAD continue to increase. This scenario raises new fundamental questions regarding the contribution of intrinsic metabolic changes in the distal affected skeletal muscle to the progression of PAD. Recent evidence suggests that disruption of skeletal muscle mitochondrial quality control triggered by intermittent ischemia-reperfusion injury is associated with increased morbidity in individuals with PAD. The mitochondrial quality control machinery relies on surveillance systems that help maintaining mitochondrial homeostasis upon stress. In this review, we describe some of the most critical mechanisms responsible for the impaired skeletal muscle mitochondrial quality control in PAD. We also discuss recent findings on the central role of mitochondrial bioenergetics and quality control mechanisms including mitochondrial fusion-fission balance, turnover, oxidative stress and aldehyde metabolism in the pathophysiology of PAD, and highlight their potential as therapeutic targets.

Antithrombotic Therapy After Peripheral Vascular Intervention

Cardioprotective medications and risk-factor modification are the hallmarks of treatment for all patients with peripheral artery disease (PAD). If symptoms are life-limiting and/or do not respond to conservative treatment, endovascular or surgical revascularization can be considered especially for patients with critical limb ischemia or acute limb ischemia. The rates of peripheral vascular intervention (PVI) have risen dramatically over the past few decades and much of this care have shifted from inpatient hospital settings to outpatient settings and office-based clinics. While PVI rates have surged and technology advancements have dramatically changed the face of PVI, the data behind optimal antithrombotic therapy following PVI is scant. Currently in the USA, most patients are treated with indefinite aspirin therapy and a variable duration of clopidogrel (or other P2Y12 inhibitor)-typically 1 month, 3 months, or indefinite therapy. More observational analyses and randomized clinical trials evaluating clinically relevant outcomes such as cardiovascular morbidity/mortality and the risk of bleeding are needed to guide the optimal role and duration of antithrombotic therapy post-PVI.

Prognostic value of ankle brachial index for future incident heart failure in patients without previous heart failure: data from the impressive predictive value of ankle brachial index for clinical long term outcome in patients with cardiovascular disease examined by ABI study

The ankle brachial index (ABI) is regarded as a predictor of future cardiovascular events. However, the relationship between ABI and incident heart failure (HF) in patients without previous HF is poorly understood. This study aimed to assess the prognostic value of ABI for incident HF in patients without previous HF. The IMPACT-ABI study was a retrospective, single-center, cohort study that enrolled and measured ABI in 3131 patients hospitalized for cardiovascular disease between January 2005 and December 2012. From this cohort, 307 patients were excluded because of previous HF and high (>1.4) ABI. The remaining 2824 patients were stratified into three groups: low ABI (≤0.9), borderline ABI (0.91-0.99), and normal ABI (1.0-1.4). The primary endpoint was hospitalization for HF. Over a mean 4.8-year follow-up, 105 cases of HF occurred. The cumulative incidence of HF was significantly higher in patients with low and borderline ABIs than in those with normal ABI (19.3 vs. 21.0 vs. 10.4 %, log rank P <0.001). In multivariate Cox proportional hazard analysis, low ABI and borderline ABI were independent predictors of incident HF [hazard ratio (HR) 3.00; 95 % confidence interval (CI) 1.70-5.28; P < 0.001 and HR 2.68; 95 % CI 1.35-5.34; P = 0.005, respectively]. In conclusion, low and borderline ABI were strong predictors for future incident HF in patients without previous HF.

Differences in galectin-3, a biomarker of fibrosis, between participants with peripheral artery disease and participants with normal ankle-brachial index

The aim of this study was to determine if galectin-3 levels were different between participants with peripheral artery disease (PAD) and controls, and to describe its relationship with markers of early atherosclerosis. Sixty participants were recruited into two groups: a PAD group (n=31), ankle-brachial index (ABI) ⩽0.90 and a normal ABI group (n=29), ABI 1.0-1.4. PAD participants were older (68.6 vs 61.8 years, p=0.037), more commonly men (68% vs 38%, p=0.02), and with more cardiovascular risk factors (p<0.001). Galectin-3 was 22% higher in PAD participants (mean±SD: 17.6±4.7 vs 14.4±4.1 ng/mL, p<0.01). The odds ratio for galectin-3 in PAD to be 1 ng/mL higher than the participants with normal ABI was 1.19, after adjusting by age and gender (p=0.014). High-sensitivity C-reactive protein (hs-CRP) and homeostatic model assessment (HOMA) were positively associated with galectin-3 in the age- and gender-adjusted model, while arterial elasticity and microalbuminuria were not. In conclusion, galectin-3 levels were higher in participants with PAD.

Chronic renal ischemia in humans: can cell therapy repair the kidney in occlusive renovascular disease?

Occlusive renovascular disease caused by atherosclerotic renal artery stenosis (ARAS) elicits complex biological responses that eventually lead to loss of kidney function. Recent studies indicate a complex interplay of oxidative stress, endothelial dysfunction, and activation of fibrogenic and inflammatory cytokines as a result of atherosclerosis, hypoxia, and renal hypoperfusion in this disorder. Human studies emphasize the limits of the kidney adaptation to reduced blood flow, eventually leading to renal hypoxia with activation of inflammatory and fibrogenic pathways. Several randomized prospective clinical trials show that stent revascularization alone in patients with atherosclerotic renal artery stenosis provides little additional benefit to medical therapy once these processes have developed and solidified. Experimental data now support developing adjunctive cell-based measures to support angiogenesis and anti-inflammatory renal repair mechanisms. These data encourage the study of endothelial progenitor cells and/or mesenchymal stem/stromal cells for the repair of damaged kidney tissue.

Incidence and Predictors of Catheterization-Related Cerebral Infarction on Diffusion-Weighted Magnetic Resonance Imaging

Introduction. The aim of this study was to examine the incidence and risk factors of catheterization-related CI in the contemporary era, using diffusion-weighted magnetic resonance imaging. Methods. We retrospectively analyzed consecutive 84 patients who underwent MRI (magnetic resonance imaging) after 2.81 ± 2.4 days (mean ± SD) of catheterization via aortic arch. We categorized the patients by the presence or absence of acute CI determined by diffusion-weighted MRI and analyzed the incidence and predictors. Results. Of 84 patients that underwent MRI after catheterization, acute CI was determined in 27 (32.1%) patients. In univariate analysis, dyslipidemia, age, coronary artery disease, antiplatelet agents, number of catheters used, urgent settings, and interventional procedures were significantly different. Multivariate analysis revealed dyslipidemia (odds ratio [OR], 4.46; 95% confidence interval [CI], 1.41–16.03; p = 0.01), higher age (OR, 1.09; 95% CI, 1.007–1.19; p = 0.03), and the number of catheters used (OR, 2.21; 95% CI, 1.21–4.36; p = 0.01) as independent predictors of the incidence of catheterization-related acute CI. Conclusions. Dyslipidemia, higher age, and number of catheters used were independent predictors for acute CI after catheterization. These findings imply that managing dyslipidemia and comprehensive planning to minimize the numbers of catheters are important.

Clinically relevant exaggerated pharmacodynamic response to dual antiplatelet therapy detected by Thromboelastogram(®) Platelet Mapping™

Dual antiplatelet therapy (DAPT) is the standard of care for primary and secondary prevention strategies in patients with coronary artery disease after stenting. Current guidelines recommend that DAPT be continued for 12 months in patients after receiving drug eluting stents. Approximately 5% of these patients will present within this 12-month period for noncardiac surgery. This case report describes a clinically relevant exaggerated pharmacodynamic response to DAPT detected by preoperative assessment of platelet function. Based on the clinical history and physical exam and subsequent lab results, a general anesthetic was performed rather than a spinal anesthetic and the surgical procedure was changed. An exaggerated pharmacodynamic response to DAPT poses its own set of risks (unexpected uncontrolled bleeding, epidural hematoma following neuraxial block placement) that point-of-care aggregation testing may decrease or mitigate by altering clinical decision making. If the clinical history and physical exam reveal possible platelet dysfunction in patients receiving DAPT, preoperative platelet function testing should be considered.

Atrial Fibrillation Increases the Risk of Peripheral Arterial Disease With Relative Complications and Mortality: A Population-Based Cohort Study

Atrial fibrillation (AF), an increasing prevalent cardiac arrhythmia due to aging general population, has many common risk factors with peripheral arterial disease (PAD). However, it is unclear whether AF is associated with a risk of PAD. We investigated the prevalence of AF and PAD in the general population and the risk of PAD among the AF population. This longitudinal, nationwide, population-based cohort study was conducted using data from the Taiwan National Health Insurance Research Database recorded during 2000 to 2011. In total, 3814 and 15,364 patients were included in the AF and non-AF cohorts, respectively. Univariate and multivariate Cox proportional hazard regression models were used for examining the effects of AF on the risk of outcomes. The average follow-up periods of PAD were 4.96 ± 3.28 and 5.29 ± 3.35 years for the AF and non-AF cohorts, respectively. Overall, the risk of PAD showed a significantly higher risk in the AF cohort (adjusted HR=1.31, 95% CI=1.19-1.45) compared with the non-AF cohort. Similar results were observed for heart failure and stroke, where the AF cohort had a 1.83-fold and 2.53-fold higher risk of developing heart failure and stroke. The AF cohort also had a significant increased risk for mortality (adjusted HR=1.66, 95% CI=1.49-1.84). The present study indicated that the incidence of PAD, heart failure, stroke, and overall mortality is higher in patients with AF than in those without it.

Myotonic Dystrophy Type 1 Complicated With Peripheral Arterial Occlusive Disease: A Case Report

Myotonic dystrophy (MD) is the most common adult muscular dystrophy characterized by multi-systemic clinical manifestations involving the brain, smooth muscle, cardiovascular and endocrine systems. However, peripheral arterial occlusive disease (PAOD) is an uncommon presentation of MD type 1 (DM1), which has not been reported in recent literature. A 53-year-old female, previously confirmed as DM1, presented with vague claudication of both lower limbs. The diagnosis of PAOD based on results of ankle-brachial index, ultrasonography, and abdominal computed tomography angiography studies was followed by aortobifemoral artery bypass surgery. Although the arterial patency was restored after the operation, she did not recover from post-operative respiratory complications. Screening of PAOD is necessary for DM1 with general risk factors of occlusive arteriopathy. However, surgery should be reserved for the most severe cases.

Borderline ankle-brachial index is associated with increased prevalence of micro- and macrovascular complications in type 2 diabetes: A cross-sectional analysis of 12,772 patients from the Joint Asia Diabetes Evaluation Program

Borderline ankle-brachial index is increasingly recognised as a marker of cardiovascular risk. We evaluated the impact of borderline ankle-brachial index in 12,772 Chinese type 2 diabetes patients from the Joint Asia Diabetes Evaluation Program between 2007 and 2012. Cardiovascular risk factors, complications and health-related quality of life were compared between patients with normal ankle-brachial index (1.0-1.4), borderline ankle-brachial index (0.90-0.99) and peripheral arterial disease (ankle-brachial index < 0.9). The prevalence of peripheral arterial disease and borderline ankle-brachial index was 4.6% and 9.6%, respectively. Borderline ankle-brachial index patients were older, more likely to be smokers and hypertensive, had longer duration of diabetes, poorer kidney function and poorer health-related quality of life than patients with normal ankle-brachial index. After adjustment for traditional cardiovascular risk factors, borderline ankle-brachial index was an independent predictor of diabetes-related micro- and macrovascular complications including retinopathy (odd ratios: 1.19 (95% confidence interval: 1.04-1.37)), macroalbuminuria (1.31 (1.10-1.56)), chronic kidney disease (1.22 (1.00-1.50)) and stroke (1.31 (1.05-1.64)). These findings suggest that patients with diabetes and borderline ankle-brachial index are at increased cardiovascular risk and may benefit from more intensive management.

High prevalence of lower extremity peripheral artery disease in type 2 diabetes patients with proliferative diabetic retinopathy

Little is known about the relationship between lower extremity peripheral arterial disease (PAD) and proliferative diabetic retinopathy (PDR) in type 2 diabetes (T2D). Here, we explored the relationship between sight-threatening PDR and PAD. We screened for diabetic retinopathy (DR) and PAD in hospitalized patients with T2D. Patients with a diabetic duration of more than 10 years, HbA1c ≥7.5%, eGFR ≥60mL/min/1.73m2 and with PDR or with no diabetic retinopathy (NDR) were eligible for this cross-sectional study. Severities of DR were graded by digital retinal photographs according to the Early Treatment Diabetic Retinopathy Study (ETDRS) scale. We assessed PAD by measuring Ankle Brachial Index (ABI), Toe Brachial Index (TBI) and Doppler ultrasound. Statistical analyses were performed using SPSS 17.0 software. Of the 1544 patients, 169 patients with extreme eye (57 PDR and 112 NDR) phenotypes met the inclusion criteria. Patients with PDR had a significantly higher proportion of low ABI (≤0.99) and high ABI (≥1.3) than patients with NDR (28.1% and 15.8% vs. 14.3% and 6.2% respectively, P<0.05). PDR patients also had lower TBI than NDR patients (0.56±0.09 vs. 0.61±0.08, P<0.01). The proportion of patients with abnormal duplex ultrasound was higher in PDR than in NDR (21.1% vs. 9.8%, P<0.001). This showed that PDR associated with PAD could be defined in multiple ways: abnormal ABI (≤0.9) (OR = 3.61, 95% CI: 1.15–11.26), abnormal TBI (OR = 2.84, 95% CI: 1.19–6.64), abnormal duplex (OR = 3.28, 95% CI: 1.00–10.71), and critical limb ischemia (OR = 5.52, 95% CI: 2.14–14.26). Moreover, PDR was a stronger independent correlation factor for PAD than a diabetic duration of 10 years. In conclusion, PAD is more common in PDR than in NDR. It implies that PDR and PAD are mostly concomitant in T2D. We should focus on screening PAD in patients with PDR in clinical practice.

Recruiting older patients with peripheral arterial disease: evaluating challenges and strategies

Peripheral arterial disease (PAD) is a group of syndromes characterized by chronic and progressive atherosclerosis with a high burden of physical disability and cardiovascular morbidity and mortality. Recruiting patients for clinical research is therefore challenging. In this article, we describe and evaluate our methods for recruiting participants for a cross-sectional feasibility study of PAD, nutritional status, and body composition. We used convenience and purposive sampling approaches to identify potential participants. Between May 2012 and April 2013, 1,446 patients were identified, and 165 patients (11.4%) responded to recruitment requests. The final enrollment was 64 participants (64/1,446; 4.4%), and four subjects (6.3%) subsequently withdrew from the study. Recruiting PAD patients presents a variety of challenges, due largely to the burdens of living with coexistent illnesses, and patients' reluctance or inability to travel for research. In this article, we delineate suggestions for improving the efficacy of recruitment methods in future PAD studies.

Infrainguinal bypass for critical limb ischemia: tips and tricks

A thoughtful but aggressive approach to care of patients with critical limb ischemia (CLI) is required to alleviate lower-extremity pain/tissue injury and achieve durable limb salvage. Specific subsets of CLI patients have been identified to clearly benefit from open surgical revascularization based on presenting signs (extensive tissue loss), multi-level, long-segment arterial occlusive disease, healthy saphenous conduit, and nondiseased tibial artery target vessel with continuous patency to the pedal arch. When other clinical scenarios exist, the treatment strategy requires consideration of patient's medical and surgical risk factors, anatomic distribution of atherosclerotic disease, and the clinical status of the limb affected by CLI. Infrainguinal saphenous vein bypass is the most durable technique for limb salvage and when properly performed is associated with excellent wound healing rates and improvement in quality of life. In this review, we detail our approach to infrainguinal arterial vein bypass in patients with CLI, including patient selection criteria, surgical planning based on arterial imaging studies, and operative technical requirements required for successful open lower-extremity bypass procedures.

Cilostazol increases patency and reduces adverse outcomes in percutaneous femoropopliteal revascularisation: a meta-analysis of randomised controlled trials

Background

Cilostazol is an oral antiplatelet agent currently indicated for treatment of intermittent claudication. There is evidence that cilostazol may reduce femoropopliteal restenosis after percutaneous endovascular intervention.

Methods

We searched PubMed, Scopus and Cochrane databases from 1966 through September 2013 for randomised controlled trials (RCTs) evaluating the addition of cilostazol to standard care in patients receiving femoropopliteal endovascular treatment. Restenosis, target lesion revascularisation and combined adverse outcomes (death, revascularisation and amputation) within 1–2 years postprocedure were evaluated.

Results

Of 205 articles, three RCTs were included in the analysis. The pooled data provided a total of 396 patients, 195 of whom received cilostazol. When compared to standard medical therapy alone, cilostazol significantly reduced the risk of restenosis (risk difference −0.20; 95% CI −0.29 to −0.11; p<0.0001; number needed to treat 5), target lesion revascularisation (risk difference −0.17; 95% CI −0.25 to −0.09; p<0.0001; number needed to treat 6). Death and amputation were not different in between groups.

Conclusions and limitation

Cilostazol significantly increases femoropopliteal patency and decreases adverse outcomes in percutaneous endovascular intervention. However, further RCTs are needed because of limited sample size; this meta-analysis represents the best current evidence.

Management of Infrapopliteal Arterial Disease: Critical Limb Ischemia

According to the TransAtlantic Inter-Society Consensus Document on Management of Peripheral Arterial Disease, "there is increasing evidence to support a recommendation for angioplasty in patients with critical limb ischemia and infrapopliteal artery occlusion." Management of infrapopliteal artery disease starts with diagnosis using modern preprocedural noninvasive and invasive imaging. Interventionalists need to learn the role of chronic total occlusion cap analysis and collateral zone recognition in angiosome-directed interventions for management of critical limb ischemia and be familiar with equipment and device selection and a stepwise approach for endovascular interventions. Interventionalists need to know which crossing tools to use to successfully cross-complex chronic total occlusion caps.

Antiplatelet Therapy for Peripheral Arterial Disease and Critical Limb Ischemia

Antiplatelet therapy is invariably prescribed for patients with peripheral arterial disease and critical limb ischemia, and numerous major society guidelines espouse their use, but high-quality data in this high-risk and challenging patient population are often lacking. This article summarizes the major guidelines for antiplatelet therapy, reviews the major studies of antiplatelet therapy in peripheral arterial disease (including data for aspirin, clopidogrel, dipyridamole, cilostazol, and prostanoids), and offers perspective on the potential benefits of ticagrelor, vorapaxar, and rivaroxaban. The review concludes with a discussion of the relative lack of efficacy that antiplatelet therapy has shown in regard to peripheral vascular outcomes.

Meta-analysis of outcomes of endovascular treatment of infrapopliteal occlusive disease with drug-eluting stents

PURPOSE

To review emerging evidence regarding the use of bare metal (BMS) vs. drug-eluting stents (DES) in the treatment of infrapopliteal occlusive disease.

METHODS

A systematic review of the literature was undertaken to identify all studies comparing stent treatments of infragenicular vessels in patients with chronic lower limb ischemia. Validated methods to assess the methodological quality of the included studies were applied. Outcome data were pooled, and combined overall effect sizes were calculated using fixed or random effects models. The search identified 4 randomized clinical trials and 2 observational studies reporting on 544 patients (287 treated with DES and 257 treated with BMS). Data are presented as the odds ratio (OR) with 95% confidence interval (CI) and the number-needed-to-treat (NNT).

RESULTS

Primary patency, freedom from target lesion revascularization, and clinical improvement at 1 year were significantly higher in the DES recipients compared to patients treated with BMS (OR 4.511, 95% CI 2.897 to 7.024, p<0.001, NNT 3.5; OR 3.238, 95% CI 2.019 to 5.192, p<0.001, NNT 6.0; and OR 1.792, 95% CI 1.039 to 3.090, p=0.036, NNT 7.3, respectively). No significant differences in limb salvage and overall survival at 1 year were identified between the groups (OR 2.008, 95% CI 0.722 to 5.585, p=0.181; OR 1.262, 95% CI 0.605 to 2.634, p=0.535, respectively). Sensitivity analyses investigating the potential effects of study design and type of DES on the combined outcome estimates validated the results.

CONCLUSION

Our analysis has demonstrated superior short-term results with DES compared with BMS, expressed by increased patency and freedom from target lesion revascularization. The influence of this finding on clinical surrogate endpoints, such as limb salvage, remains unknown.

Coexistence of pheochromocytoma with abdominal aortic aneurysm: an untold association

Pheochromocytomas have been described in association with rare vascular abnormalities, most common of them being renal artery stenosis. A 45-year-old woman was admitted to our hospital with complaints of headache, sweating, anxiety, dizziness, nausea, vomiting and severe hypertension. For the last several days, she was having a dull aching abdominal pain with a palpable, pulsatile, expansile and non-tender mass in the epigastric region. Hypertension was confirmed biochemically to result from excess catecholamine production. Abdominal computed tomography revealed the presence of a right adrenal pheochromocytoma. Magnetic resonance imaging of the abdomen demonstrated an abdominal aortic aneurysm (AAA) of maximum transverse diameter of 4.5 cm with 3 cm lumen. Surgical removal of pheochromocytoma resulted in normalization of blood pressure to normal. Because of the asymptomatic 4.5 cm aneurysm, our patient was advised for periodic follow-up. To our belief, this is the first such case report emanating from India, citing this rare association between pheochromocytoma and AAA. It is concluded that when the two diseases occur simultaneously, both must be diagnosed accurately and treated adequately. Possible mechanisms of such an uncommon association are also discussed.