Effectiveness of combined therapy with angiotensin-converting enzyme inhibitors and statins in reducing mortality in diabetic patients with critical limb ischemia: an observational study

Angiotensin-converting enzyme inhibitors and angiotensin receptor blockers are associated with improved amputation-free survival in chronic limb-threatening ischemia

BACKGROUND

In the Heart Outcomes Prevention Evaluation study, investigators found that ramipril was associated with improved survival as well as decreased MI and stroke rates in patients with peripheral arterial disease. Nonetheless, their effect on chronic limb-threatening ischemia (CLTI)-specific outcomes is unclear. We aim to assess the effect of ACEIs/ARBs on amputation-free survival in patients with CLTI undergoing peripheral vascular intervention (PVI) in a Medicare-linked database.

METHODS

Patients undergoing PVI in the Vascular Quality Initiative Vascular Implant Surveillance and Interventional Outcomes Network database were included. Primary outcomes included amputation-free survival. Kaplan-Meier survival and multivariable Cox regression analyses were used to assess 1-year outcomes.

RESULTS

A total of 34,284 patients were included, 46.3% of whom were discharged on ACEIs/ARBs. Patients discharged on ACEIs/ARBs were more likely to be smokers, have diabetes, and have hypertension. They were also more likely to present with rest pain. The overall 1-year survival rate for patients on ACEIs/ARBs vs those who are not was (79.1% vs 69.4%; P < .001). Freedom from amputation was 87.8% for patients on ACEIs/ARBs vs 84.2% for those who were not (P < .001). Amputation-free survival was 70.5% vs 59.5% for ACEIs/ARBs vs no ACEIs/ARBs (P < .001). After adjusting for potential confounders, ACEIs/ARBs use was associated with lower 1-year mortality (hazard ratio [HR], 0.77; 95% confidence interval [CI], 0.7-0.8; P < .001), amputation (HR, 0.89; 95% CI, 0.8-0.9; P < .001), and amputation or death (HR, 0.79; 95% CI, 0.76-0.8; P < .001).

CONCLUSIONS

ACEIs/ARBs were associated independently with lower amputation, improved survival, and amputation-free rates survival at 1 year in patients with CLTI undergoing PVI. The fact that more than one-half the patients were not discharged on these medications presents an area for potential quality improvement.

Amputation-free survival in the long-term follow-up and gender-related characteristics in patients revascularized for critical limb ischemia

OBJECTIVE

Patients with Critical Limb Ischemia (CLI) present a high risk of cardiovascular events and death. Revascularization is the cornerstone of therapy to relieve ischemic pain and prevent limb loss. Literature data suggest that women tend to present with worse outcomes after revascularization. The aim of the present study is to determine amputation-free survival in a long-term follow-up in women and men following endovascular revascularization procedure for CLI.

METHODS

From November 2013 to December 2020, 357 consecutive patients were retrospectively included. Clinical and biological parameters were recorded at baseline before endovascular revascularization. During follow-up until February 2023, overall survival and amputation-free survival (freedom from major amputation) were analysed using the Kaplan-Meier method. Univariate and multivariate analyses were performed to study the parameters associated with amputation-free survival. A P<0.05 was considered as statistically significant.

RESULTS

A total of 357 consecutive patients were included, 189 men and 168 women with CLI, with a mean age of 78.6±12 years. Treated hypertension (79%), diabetes mellitus (48%), coronary artery disease (39%) and protein malnutrition (61%) were the most prevalent comorbidities. Women were older than men with a mean age of 82.4±11.4 years (versus 75.4±11 years in men) and presented more frequently with protein malnutrition (70% of women). Prevalence of diabetes, tobacco use and history of coronary heart disease were significantly higher in men. During the 10-year follow-up period, 241 patients had died (68%) and 38 (11%) underwent major amputation, of whom 22 patients were still alive on February 2023. Median survival was 35.5 months [IQR: 29.5; 43] in the overall population, 38.5 [32; 50.4] months in women and 33.5 months [24.7; 43.5] in men. No gender-related differences were noted according to peri-procedural complications, survival probability and amputation-free survival. In multivariate analysis for amputation-free survival, age, previous coronary heart disease, C-reactive protein level, left ventricular ejection fraction (LVEF)<60% and albumin level<35g/L were correlated with poor outcome. In particular, protein malnutrition, as a treatable risk factor, appears significantly correlated with poor outcome in both men and women (HR=2.50 [1.16;5.38], P=0.0196 in men; HR=1.77 [1.00;3.13], P=0.049 in women).

CONCLUSION

The present results highlight that mortality in patients after endovascular revascularization remains high with a mortality rate of 28% at 1 year, 40% at 2 years and 51% at 3 years. Women represented a distinct population, almost 10-year older than their male counterparts, with more prevalent protein malnutrition. However, no gender-related difference was noted according to amputation-free survival on the long-term follow-up. Associated risk factors are mainly age, a history of coronary heart disease, pre-procedural inflammatory syndrome and protein malnutrition. Correction of malnutrition could have the potential to improve functional and general long-term prognosis in patients with CLI together with optimal medical and interventional management.

Sex-Related Differences and Factors Associated with Peri-Procedural and 1 Year Mortality in Chronic Limb-Threatening Ischemia Patients from the CLIMATE Italian Registry

BACKGROUND

Identifying sex-related differences/variables associated with 30 day/1 year mortality in patients with chronic limb-threatening ischemia (CLTI).

METHODS

Multicenter/retrospective/observational study. A database was sent to all the Italian vascular surgeries to collect all the patients operated on for CLTI in 2019. Acute lower-limb ischemia and neuropathic-diabetic foot are not included.

FOLLOW-UP

One year. Data on demographics/comorbidities, treatments/outcomes, and 30 day/1 year mortality were investigated.

RESULTS

Information on 2399 cases (69.8% men) from 36/143 (25.2%) centers. Median (IQR) age: 73 (66-80) and 79 (71-85) years for men/women, respectively (p < 0.0001). Women were more likely to be over 75 (63.2% vs. 40.1%, p = 0.0001). More men smokers (73.7% vs. 42.2%, p < 0.0001), are on hemodialysis (10.1% vs. 6.7%, p = 0.006), affected by diabetes (61.9% vs. 52.8%, p < 0.0001), dyslipidemia (69.3% vs. 61.3%, p < 0.0001), hypertension (91.8% vs. 88.5%, p = 0.011), coronaropathy (43.9% vs. 29.4%, p < 0.0001), bronchopneumopathy (37.1% vs. 25.6%, p < 0.0001), underwent more open/hybrid surgeries (37.9% vs. 28.8%, p < 0.0001), and minor amputations (22% vs. 13.7%, p < 0.0001). More women underwent endovascular revascularizations (61.6% vs. 55.2%, p = 0.004), major amputations (9.6% vs. 6.9%, p = 0.024), and obtained limb-salvage if with limited gangrene (50.8% vs. 44.9%, p = 0.017). Age > 75 (HR = 3.63, p = 0.003) is associated with 30 day mortality. Age > 75 (HR = 2.14, p < 0.0001), nephropathy (HR = 1.54, p < 0.0001), coronaropathy (HR = 1.26, p = 0.036), and infection/necrosis of the foot (dry, HR = 1.42, p = 0.040; wet, HR = 2.04, p < 0.0001) are associated with 1 year mortality. No sex-linked difference in mortality statistics.

CONCLUSION

Women exhibit fewer comorbidities but are struck by CLTI when over 75, a factor associated with short- and mid-term mortality, explaining why mortality does not statistically differ between the sexes.

Peri-procedural complications following endovascular revascularization for critical limb ischemia

OBJECTIVE

Revascularization procedures are considered the cornerstone of therapy in patients with critical limb ischemia (CLI) and multiple procedures are often required to attain limb salvage. The aim of the present study is to determine the prevalence of peri-procedural complications after endovascular procedure, and to determine the clinical and biological characteristics of patients associated to the risk of peri-procedural complications.

METHODS

From November 2013 to May 2021, 324 consecutive patients were retrospectively included, of whom 99 underwent more than one revascularization procedure for contralateral CLI or clinical recurrence of CLI. A total of 532 revascularizations were performed. Clinical and biological parameters were recorded at baseline before endovascular revascularization. The occurrence of a peri-procedural complication (local complications, fatal and non-fatal major bleeding or cardiovascular events) was recorded up to 30days after revascularization. Univariate and multivariate analyses were performed to study the parameters associated with per-procedural complications. A P<0.05 was considered as statistically significant.

RESULTS

A total of 324 consecutive patients were included, 177 men and 147 women with CLI, with a mean age of 77.6±11.9years. Most of these patients had cardiovascular comorbidities (41% with a history of coronary heart disease, 78% treated hypertensive patients, 49% diabetic patients). Peri-procedural mortality occurred in 13 patients (4%) and 9 patients (2.8%) experienced major amputation at one-month following revascularization. Among the 532 revascularization procedures, 99 major bleeding events (22.8% of the cohort population) and 31 cardiovascular events (8.6% of the cohort population), were recorded in the peri-procedural period. Cardiovascular events were associated with peri-procedural mortality. Complications at the puncture site occurred during 38 of the 532 procedures (10.2% of the cohort population). Compared with patients undergoing a single revascularization procedure, patients with multiple procedures presented a higher risk of major bleeding events (48.5% vs. 11.6%, P<0.0001) and access site complications (20.2% vs. 5.78%, P<0.0001). In multivariate analysis, pulse pressure <60mmHg and hemoglobin level <10g/dl were correlated with the occurrence of major bleeding events; left ventricular ejection fraction<60% and the absence of statin treatment were correlated with the occurrence of cardiovascular complications; a high chronological rank of revascularization was correlated with the occurrence of local complication. Finally, age and gender were not associated with the occurrence of peri-procedural complication.

CONCLUSION

The present results highlight that multiple revascularization procedures for limb salvage are required in almost one third of the population with critical limb ischemia and were associated with the risk of major bleeding events and access site complications. The most frequent complications of peripheral vascular interventions were major bleeding events. Adverse cardiovascular events were related with peri-procedural mortality. Anemia, blood pressure, left ventricular ejection fraction and statin treatment are important parameters to consider for peri-procedural outcomes, independently of age, gender and the chronological rank of revascularization procedure.

Control of aging by the renin–angiotensin system: a review of C. elegans, Drosophila, and mammals

The free-living, non-parasitic nematode Caenorhabditis elegans is a premier model organism for the study of aging and longevity due to its short lifespan, powerful genetic tools, and conservation of fundamental mechanisms with mammals. Approximately 70 percent of human genes have homologs in C. elegans, including many that encode proteins in pathways that influence aging. Numerous genetic pathways have been identified in C. elegans that affect lifespan, including the dietary restriction pathway, the insulin/insulin-like growth factor (IGF) signaling pathway, and the disruption of components of the mitochondrial electron transport chain. C. elegans is also a powerful system for performing drug screens, and many lifespan-extending compounds have been reported; notably, several FDA-approved medications extend the lifespan in C. elegans, raising the possibility that they can also extend the lifespan in humans. The renin–angiotensin system (RAS) in mammals is an endocrine system that regulates blood pressure and a paracrine system that acts in a wide range of tissues to control physiological processes; it is a popular target for drugs that reduce blood pressure, including angiotensin-converting enzyme (ACE) inhibitors and angiotensin II receptor blockers (ARBs). Emerging evidence indicates that this system influences aging. In C. elegans, decreasing the activity of the ACE homolog acn-1 or treatment with the ACE-inhibitor Captopril significantly extends the lifespan. In Drosophila, treatment with ACE inhibitors extends the lifespan. In rodents, manipulating the RAS with genetic or pharmacological interventions can extend the lifespan. In humans, polymorphisms in the ACE gene are associated with extreme longevity. These results suggest the RAS plays a conserved role in controlling longevity. Here, we review studies of the RAS and aging, emphasizing the potential of C. elegans as a model for understanding the mechanism of lifespan control.

Cardiovascular and Limb Events Following Endovascular Revascularization Among Patients ≥65 Years Old: An American College of Cardiology PVI Registry Analysis

Background We aimed to characterize the occurrence of major adverse cardiovascular and limb events (MACE and MALE) among patients with peripheral artery disease (PAD) undergoing peripheral vascular intervention (PVI), as well as associated factors in patients with chronic limb threatening ischemia (CLTI). Methods and Results Patients undergoing PVI in the American College of Cardiology's (ACC) National Cardiovascular Data Registry's PVI Registry who could be linked to Centers for Medicare and Medicaid Services data were included. The primary outcomes were MACE, MALE, and readmission within 1 month and 1 year following index CLTI-PVI or non-CLTI-PVI. Cox proportional hazards regression was used to identify factors associated with the development of the primary outcomes among patients undergoing CLTI-PVI. There were 1758 (49.7%) patients undergoing CLTI-PVI and 1779 (50.3%) undergoing non-CLTI-PVI. By 1 year, MACE occurred in 29.5% of patients with CLTI (n=519), and MALE occurred in 34.0% of patients with CLTI (n=598). By 1 year, MACE occurred in 8.2% of patients with non-CLTI (n=146), and MALE occurred in 26.1% of patients with non-CLTI (n=465). Predictors of MACE at 1 year in CLTI-PVI included end-stage renal disease on hemodialysis, congestive heart failure, prior CABG, and severe lung disease. Predictors of MALE at 1 year in CLTI-PVI included treatment of a prior bypass graft, profunda femoral artery treatment, end-stage renal disease on hemodialysis, and treatment of a previously treated lesion. Conclusions Patients ≥65 years old undergoing PVI experience high rates of MACE and MALE. A range of modifiable and non-modifiable patient factors, procedural characteristics, and medications are associated with the occurrence of MACE and MALE following CLTI-PVI.

Synergistic actions between angiotensin-converting enzyme inhibitors and statins in atherosclerosis

AIMS

Hypertension and hypercholesterolemia are independent risk factors for atherosclerotic cardiovascular disease (ASCVD) by acting directly on the endothelium and activating the renin-angiotensin aldosterone system (RAAS) and mevalonate pathways. This review examines how the severity and duration of these risk factors may influence the cardiovascular risk through a reciprocal interplay leading to oxidative stress and pro-inflammatory response.

DATA SYNTHESIS

The review highlights the clinical evidence supporting the benefits of statins and angiotensin-converting enzyme (ACE) inhibitors for hypertension, lipid disorders and ASCVD management, both individually and combined, at all stages of the cardiovascular continuum.

CONCLUSION

Drug strategies incorporating an ACE-inhibitor and a statin, and in particular perindopril and atorvastatin, have consistently demonstrated reductions in the rate of ASCVD events in patients with hypertension and lipid disorders, cementing their position as first-line therapies for the management of atherosclerosis complications.

Effects of Statin Therapy and Dose on Cardiovascular and Limb Outcomes in Peripheral Arterial Disease: A Systematic Review and Meta-analysis

OBJECTIVE

Statin therapy is indicated in patients with peripheral arterial disease (PAD). National Institute for Health and Care Excellence guidelines suggest the use of "high intensity" statins, although evidence with PAD specific data are lacking. The effect of statin therapy and dose on outcomes in PAD is investigated.

DATA SOURCES

Studies measuring statin use in PAD patients and outcomes were identified based on the Preferred Reporting Items for Systematic Reviews and Meta-Analyses (PRISMA) criteria. The EMBASE and MEDLINE databases were interrogated from January 1957 until February 2020. Twenty-two observational cohort studies and two randomised control trials were included (n = 268 611).

REVIEW METHODS

Pooled estimates of dichotomous outcome data were calculated using the odds/hazard ratios (OR/HR) and 95% confidence interval (CI). Meta-analysis was conducted using the inverse variance or Mantel-Haenszel method. Outcomes included all cause mortality (ACM), cardiovascular mortality (CVM), major adverse cardiac events (MACE), and amputation. Subgroup analysis was performed on studies comparing patients taking high dose vs. combined low and moderate doses of statins. The GRADE criteria assessed the quality of evidence for outcomes.

RESULTS

Statin therapy (vs. no statins) was significantly protective for ACM: OR 0.68 (95% CI 0.60 - 0.76) (number needed to treat [NNT] = 48), HR 0.74 (95% CI 0.70 - 0.78) (NNT = 10 - 91); MACE: OR 0.84 (95% CI 0.78 - 0.92) (NNT = 53), HR 0.78 (95% CI 0.65 - 0.93) (NNT = 167); and amputations: OR 0.59 (95% CI 0.33 - 1.07) (NNT = 333), HR 0.74 (95% CI 0.62 - 0.89) (NNT = 50). High doses of statins (vs. combined low and moderate doses) were significantly better protective against ACM OR 0.69 (95% CI 0.43 - 1.09) (NNT = 17), HR 0.74 (95% CI 0.62 - 0.89) (NNT = 16 - 200) but work less significantly for MACE OR 0.77 (95% CI 0.49 - 1.21) (NNT = 25). Amputations were less frequent in patients on high doses HR 0.78 (95% CI 0.69 - 0.90) (NNT = 53 - 1 000).

CONCLUSION

Higher dosing of statins confers a significant improvement in patient outcomes, especially ACM and amputations, although the quality of the evidence was variable. Such findings require confirmation in larger, PAD specific trials.

Medical therapy for cardiovascular and limb-related risk reduction in critical limb ischemia

Critical limb ischemia (CLI) constitutes the most advanced form of peripheral artery disease (PAD) and is characterized by ischemic rest pain, tissue loss and/or gangrene. Optimized medical care and risk factor modification in addition to revascularization could reduce the incidence of cardiovascular events and major adverse limb events, improving patients' quality of life and promising higher survival rates. Adequate adherence to cardioprotective medications, including antithrombotic therapy (e.g., antiplatelets, anticoagulants), cholesterol-lowering agents (e.g., statins, proprotein convertase subtilisin/kexin type 9 (PCSK9) inhibitors), angiotensin-converting enzyme (ACE) inhibitors or angiotensin receptor blockers (ARBs), and smoking cessation should be strongly encouraged for patients with CLI. This review examines these guideline-recommended therapies in terms of cardiovascular and limb-related risk reduction in patients with CLI.

Peripheral Arterial Disease in Persons with Diabetic Foot Ulceration: a Current Comprehensive Overview

In developed countries, the prevalence of persons with diabetes and peripheral arterial disease (PAD) is approximately 50%. The presence of PAD is associated with non-healing ulcers, major amputation, cardiovascular morbidity, and mortality. It is estimated that persons with diabetes, foot ulceration and PAD have 50% of 5-years mortality rate. Therefore, subjects with ischemic diabetic foot ulcers (DFUs) should be considered a special group of patients with specific clinical characteristics, general health status and prognosis. In persons with ischemic DFUs, an early diagnosis and treatment are mandatory to reduce the risk of worse outcomes such as major amputation. Revascularization of occluded lower extremity arteries is the main treatment to restore blood flow in the foot and promote wound healing. Nonetheless, there are several unmet needs in the management of diabetic subjects with PAD and foot ulceration as medical therapy, diagnostic criteria and indications for revascularization, revascularization strategy and technical approach as well as the management of no-option critical limb ischemia patients. It is a common opinion that there is an evolution of PAD features in diabetic persons, which seems to present a more aggressive pattern. This may be related to the frequent presence of concomitant comorbidities such as renal failure which could influence the characteristics of atherosclerotic plaques and their distribution. The aim of this review is to commence a complete overview and state of the art in the treatment of patients with diabetes, PAD, and foot ulceration and to describe the current challenges and future perspectives.

Long-Term Effectiveness and Safety of Initiating Statin Therapy After Index Revascularization In Patients With Peripheral Arterial Occlusive Disease

Background An increasing number of patients with a peripheral arterial occlusive disease were put on statins during the past years. This study assessed whether statin therapy was effective and safe for these new users. Methods and Results Using health insurance claims data from Germany's second-largest insurance fund, BARMER, we identified patients with peripheral arterial occlusive disease who had index revascularization between 2008 and 2018 without prior statin therapy. We compared patients with and without statin therapy in addition to antithrombotics during the first quarter after discharge (new users versus nonusers). Outcomes were all-cause mortality, cardiovascular events, and incident major amputation for effectiveness and incident diabetes mellitus and incident myopathy for safety. Propensity score matching was used to balance the study groups. All analyses were stratified into patients with chronic limb-threatening ischemia and intermittent claudication. A total of 22 208 patients (mean age 71.1 years and 50.3% women) were included in the study. In 10 922 matched patients, statin initiation was associated with lower all-cause mortality (chronic limb-threatening ischemia: hazard ratio [HR], 0.75 [95% CI, 0.68-0.84]; intermittent claudication: HR, 0.80 [95% CI, 0.70-0.92]), lower risk of major amputation in patients with chronic limb-threatening ischemia (HR, 0.73; 95% CI, 0.58-0.93) and lower risk of cardiovascular events (hazard ratio, 0.80; 95% CI, 0.70-0.92) in patients with intermittent claudication during 5 years of follow-up. Safety outcomes did not differ among the study groups. Conclusions Initiating statin therapy in patients with peripheral arterial occlusive disease after index revascularization is efficient and safe with an effect size comparable to earlier studies. Awareness campaigns for evidence-based optimal pharmacological treatment among patients are recommended.

Improved survival with angiotensin-converting enzyme inhibitors and angiotensin receptor blockers in chronic limb-threatening ischemia

OBJECTIVE

Angiotensin-converting enzyme (ACE) inhibitors and angiotensin receptor blockers (ARBs) reduce the risk of cardiovascular events in patients with peripheral artery disease. However, their effect on limb-specific outcomes is unclear. The objective of this study was to assess the effect of ACE inhibitors/ARBs on limb salvage (LS) and survival in patients undergoing peripheral vascular intervention (PVI) for chronic limb-threatening ischemia (CLTI).

METHODS

The Vascular Quality Initiative registry was used to identify patients undergoing PVI for CLTI between April 1, 2010, and June 1, 2017. Patients with complete comorbidity, procedural, and follow-up limb and survival data were included. Propensity score matching was performed to control for baseline differences between the groups. LS, amputation-free survival (AFS), and overall survival (OS) were calculated in matched samples using Kaplan-Meier analysis.

RESULTS

A total of 12,433 limbs (11,331 patients) were included. The ACE inhibitors/ARBs group of patients had significantly higher prevalence of coronary artery disease (31% vs 27%; P < .001), diabetes (67% vs 57%; P < .001), and hypertension (94% vs 84%; P < .001) and lower incidence of end-stage renal disease (7% vs 12%; P < .001). Indication for intervention was tissue loss in 64% of the ACE inhibitors/ARBs group vs 66% in the no ACE inhibitors/ARBs group (P = .005). Postmatching survival analysis at 5 years showed improved OS (81.8% vs 79.9%; P = .01) and AFS (73% vs 71.5%; P = .04) with ACE inhibitors/ARBs but no difference in LS (ACE inhibitors/ARBs, 88.3%; no ACE inhibitors/ARBs, 88.1%; P = .56). After adjustment for multiple variables in a Cox regression model, ACE inhibitors/ARBs were associated with improved OS (hazard ratio, 0.89; 95% confidence interval, 0.80-0.99; P = .03) and AFS (hazard ratio, 0.92; 95% confidence interval, 0.84-0.99; P = .04).

CONCLUSIONS

ACE inhibitors/ARBs are independently associated with improved survival and AFS in patients undergoing PVI for CLTI. LS rates remained unaffected. Further research is required to investigate the use of ACE inhibitors/ARBs in this population of patients, especially CLTI patients with other indications for therapy with ACE inhibitors/ARBs.

Statin therapy for reduction of cardiovascular and limb-related events in critical limb ischemia: A systematic review and meta-analysis

High-intensity statins are recommended for patients with peripheral artery disease (PAD). Critical limb ischemia (CLI) is the most advanced presentation of PAD. The benefit of statins in the CLI population is unclear based on the existent studies. Our objective was to perform a systematic review and meta-analysis regarding the efficacy of statin therapy in patients with CLI. PRISMA guidelines were followed. PubMed, EMBASE, and Cochrane CENTRAL databases were reviewed up to April 30, 2019. The primary outcomes included amputation rates and all-cause mortality. Secondary outcomes included primary patency rates, amputation-free survival and major adverse cardiac or cerebrovascular events (MACCE). Risk of bias was assessed with the Robins-I tool for observational studies. A random-effects model meta-analysis was performed. Heterogeneity was assessed with I2. Funnel plots and Egger’s test were used to assess publication bias. Nineteen studies including 26,985 patients with CLI were included in this systematic review. Among patients with known data on statin status, 12,292 (49.6%) were on statins versus 12,513 (50.4%) not on statins. Patients treated with statins were 25% less likely to undergo amputation (HR 0.75; 95% CI: 0.59–0.95; I2 = 79%) and 38% less likely to have a fatal event (HR 0.62; 95% CI: 0.52–0.75; I2 = 41.2%). Statin therapy was also associated with increased overall patency rates and lower incidence of MACCE. There was substantial heterogeneity in the analysis for amputation and amputation-free survival (I2 > 70%). In conclusion, statins are associated with decreased risk for amputation, mortality, and MACCE, as well as increased overall patency rates among patients with CLI. Future studies should assess whether other lipid-lowering medications in addition to high-intensity statins can further improve outcomes among patients with CLI. (PROSPERO registration number: CRD42019134160)

Angiotensin Converting Enzyme Inhibitors and Angiotensin II Receptor Blockers (ACEI/ARB) are Associated with Improved Limb Salvage after Infrapopliteal Interventions for Critical Limb Ischemia

BACKGROUND

Angiotensin-converting enzyme Inhibitors and Angiotensin II Receptor Blockers (ACEI/ARB) reduce the risk of cardiovascular events and mortality in patients with peripheral arterial disease (PAD). However, their effect on limb-specific outcomes is unclear. The objective of this study is to assess the effect of ACEI/ARB on patency and limb salvage in patients undergoing interventions for critical limb ischemia (CLI).

METHODS

Patients undergoing infrainguinal revascularization for CLI (Rutherford 4-6) between 06/2001 and 12/2014 were retrospectively identified. Primary Patency (PP), Secondary Patency (SP), Limb Salvage (LS), major adverse cardiac events (MACE), and survival rates were calculated using Kaplan-Meier. Multivariate analysis was performed using Cox regression.

RESULTS

A total of 755 limbs in 611 patients (311 ACEI/ARB, 300 No ACEI/ARB) were identified. Hypertension (86% vs. 70%, P < 0.001), diabetes (68% vs. 55%, P = 0.001) and statin use (61% vs. 45%, P < 0.001) were significantly greater in the ACEI/ARB group. Interventions were performed mostly for tissue loss (83% ACEI/ARB vs. 84% No ACEI/ARB, P = 0.73). Comparing ACEI/ARB versus No ACEI/ARB, in femoropopliteal interventions, 60-month PP (54% vs. 55%, P = 0.47), SP (76% vs. 75%, P = 0.83) and LS (84% vs. 87%, P = 0.36) were not significantly different. In infrapopliteal interventions, 60-month PP (45% vs. 46%, P = 0.66) and SP (62% vs. 75%, P = 0.96) were not significantly different. LS was significantly greater in ACEI/ARB (75%), as compared to No ACEI/ARB (61%) (P = 0.005). Cox regression identified diabetes (HR 2.4 (1.4-4.1), P = 0.002), ESRD (HR 3.5 (2.1-5.7), P < 0.001), hypertension (HR 0.4 (0.2-0.6), P < 0.001), and ACEI/ARB (HR 0.6 (0.4-0.9), P = 0.03), as factors independently associated with LS after infrapopliteal interventions. Freedom from MACE (ACEI/ARB 37% vs. 32%, P = 0.82) and overall survival (ACEI/ARB 42% vs. 35% No ACEI/ARB, P = 0.84) were not significantly different.

CONCLUSIONS

ACEI/ARB is associated with improved limb salvage in CLI patients undergoing infrapopliteal interventions, but not after femoropopliteal interventions. ACEI/ARB had no impact on patency rates. They were also associated with a trend toward improved survival and freedom from MACE. Our findings suggest that the use of ACEI/ARB may improve outcomes in the high-risk CLI patient population.

Medical adjunctive therapy for patients with chronic limb-threatening ischemia: a systematic review

INTRODUCTION

The aim of this article is to systematically review the literature on medical adjunctive therapy for patients with chronic limb-threatening ischemia (CLTI).

EVIDENCE ACQUISITION

MEDLINE, Embase, and Cochrane Database of Systematic Reviews were searched for studies published between January 1st, 2009, and June 1st, 2019. Articles that studied medical treatment of CLTI patients and reported clinical outcomes were eligible. Main exclusion criteria were case reports <20 patients, incorrect publication type, and CLTI caused by Buerger disease. The primary end point was major amputation (above the ankle) in studies with a follow-up of ≥6 months. Secondary end points were other clinical end points such as death and wound healing. Study quality was assessed according to the Downs and Black checklist.

EVIDENCE SYNTHESIS

Included were 42 articles: four focused on antiplatelet therapy, five on antihypertensive medication, 6 on lipid-lowering therapy, 16 on stem cell therapy, three on growth factors, five on prostanoids, and one study each on cilostazol, glucose-lowering therapy, spinal cord stimulation, sulodexide, and hemodilution. Calcium channel blockers, iloprost, cilostazol, and hemodilution showed significant improvement of limb salvage, but data are limited. Stem cell therapy showed no significant improvement of limb salvage but could potentially improve wound healing. Antiplatelets, antihypertensives, and statins showed significantly lower cardiovascular events rates but not evident lower major amputation rates. The quality of the studies was fair to good.

CONCLUSIONS

Certain medical therapies serve to improve limb salvage next to revascularization in CLTI patients, whereas others are important in secondary prevention. Because high quality evidence is limited, further research is needed.

Global Vascular Guidelines on the Management of Chronic Limb-Threatening Ischemia

GUIDELINE SUMMARY

Chronic limb-threatening ischemia (CLTI) is associated with mortality, amputation, and impaired quality of life. These Global Vascular Guidelines (GVG) are focused on definition, evaluation, and management of CLTI with the goals of improving evidence-based care and highlighting critical research needs. The term CLTI is preferred over critical limb ischemia, as the latter implies threshold values of impaired perfusion rather than a continuum. CLTI is a clinical syndrome defined by the presence of peripheral artery disease (PAD) in combination with rest pain, gangrene, or a lower limb ulceration >2 weeks duration. Venous, traumatic, embolic, and nonatherosclerotic etiologies are excluded. All patients with suspected CLTI should be referred urgently to a vascular specialist. Accurately staging the severity of limb threat is fundamental, and the Society for Vascular Surgery Threatened Limb Classification system, based on grading of Wounds, Ischemia, and foot Infection (WIfI) is endorsed. Objective hemodynamic testing, including toe pressures as the preferred measure, is required to assess CLTI. Evidence-based revascularization (EBR) hinges on three independent axes: Patient risk, Limb severity, and ANatomic complexity (PLAN). Average-risk and high-risk patients are defined by estimated procedural and 2-year all-cause mortality. The GVG proposes a new Global Anatomic Staging System (GLASS), which involves defining a preferred target artery path (TAP) and then estimating limb-based patency (LBP), resulting in three stages of complexity for intervention. The optimal revascularization strategy is also influenced by the availability of autogenous vein for open bypass surgery. Recommendations for EBR are based on best available data, pending level 1 evidence from ongoing trials. Vein bypass may be preferred for average-risk patients with advanced limb threat and high complexity disease, while those with less complex anatomy, intermediate severity limb threat, or high patient risk may be favored for endovascular intervention. All patients with CLTI should be afforded best medical therapy including the use of antithrombotic, lipid-lowering, antihypertensive, and glycemic control agents, as well as counseling on smoking cessation, diet, exercise, and preventive foot care. Following EBR, long-term limb surveillance is advised. The effectiveness of nonrevascularization therapies (eg, spinal stimulation, pneumatic compression, prostanoids, and hyperbaric oxygen) has not been established. Regenerative medicine approaches (eg, cell, gene therapies) for CLTI should be restricted to rigorously conducted randomizsed clinical trials. The GVG promotes standardization of study designs and end points for clinical trials in CLTI. The importance of multidisciplinary teams and centers of excellence for amputation prevention is stressed as a key health system initiative.

Global vascular guidelines on the management of chronic limb-threatening ischemia

Chronic limb-threatening ischemia (CLTI) is associated with mortality, amputation, and impaired quality of life. These Global Vascular Guidelines (GVG) are focused on definition, evaluation, and management of CLTI with the goals of improving evidence-based care and highlighting critical research needs. The term CLTI is preferred over critical limb ischemia, as the latter implies threshold values of impaired perfusion rather than a continuum. CLTI is a clinical syndrome defined by the presence of peripheral artery disease (PAD) in combination with rest pain, gangrene, or a lower limb ulceration >2 weeks duration. Venous, traumatic, embolic, and nonatherosclerotic etiologies are excluded. All patients with suspected CLTI should be referred urgently to a vascular specialist. Accurately staging the severity of limb threat is fundamental, and the Society for Vascular Surgery Threatened Limb Classification system, based on grading of Wounds, Ischemia, and foot Infection (WIfI) is endorsed. Objective hemodynamic testing, including toe pressures as the preferred measure, is required to assess CLTI. Evidence-based revascularization (EBR) hinges on three independent axes: Patient risk, Limb severity, and ANatomic complexity (PLAN). Average-risk and high-risk patients are defined by estimated procedural and 2-year all-cause mortality. The GVG proposes a new Global Anatomic Staging System (GLASS), which involves defining a preferred target artery path (TAP) and then estimating limb-based patency (LBP), resulting in three stages of complexity for intervention. The optimal revascularization strategy is also influenced by the availability of autogenous vein for open bypass surgery. Recommendations for EBR are based on best available data, pending level 1 evidence from ongoing trials. Vein bypass may be preferred for average-risk patients with advanced limb threat and high complexity disease, while those with less complex anatomy, intermediate severity limb threat, or high patient risk may be favored for endovascular intervention. All patients with CLTI should be afforded best medical therapy including the use of antithrombotic, lipid-lowering, antihypertensive, and glycemic control agents, as well as counseling on smoking cessation, diet, exercise, and preventive foot care. Following EBR, long-term limb surveillance is advised. The effectiveness of nonrevascularization therapies (eg, spinal stimulation, pneumatic compression, prostanoids, and hyperbaric oxygen) has not been established. Regenerative medicine approaches (eg, cell, gene therapies) for CLTI should be restricted to rigorously conducted randomizsed clinical trials. The GVG promotes standardization of study designs and end points for clinical trials in CLTI. The importance of multidisciplinary teams and centers of excellence for amputation prevention is stressed as a key health system initiative.

Statin therapy improved long-term prognosis in patients with major non-cardiac vascular surgeries: a systematic review and meta-analysis

OBJECTIVE

To investigate whether statin intervention will improve the long-term prognosis of patients undergoing major non-cardiac vascular surgeries.

METHODS

Major database searches for clinical trials enrolling patients undergoing major non-cardiac vascular surgeries, including lower limb revascularization, carotid artery surgeries, arteriovenous fistula, and aortic surgeries, were performed. Subgroup analyses, stratified by surgical types or study types, were employed to obtain statistical results regarding survival, patency rates, amputation, and cardiovascular and stroke events. Odds ratio (ORs) and 95% confidence intervals (CIs) were calculated by Review Manager 5.3. Sensitivity analysis, publication bias and meta-regression were conducted by Stata 14.0.

RESULTS

In total, 34 observational studies, 8 prospective cohort studies and 4 randomized controlled clinical trials (RCTs) were enrolled in the present analysis. It was demonstrated that statin usage improved all-cause mortality in lower limb, carotid, aortic and mixed types of vascular surgery subgroups compared with those in which statins were not used. Additionally, the employment of statins efficiently enhanced the primary and secondary patency rates and significantly decreased the amputation rates in the lower limb revascularization subgroup. Furthermore, for other complications, statin intervention decreased cardiovascular events in mixed types of vascular surgeries and stroke incidence in the carotid surgery subgroup. No significant publication bias was observed. The meta-regression results showed that the morbidity of cardiovascular disease or the use of aspirin might affect the overall estimates in several subgroups.

CONCLUSIONS

This meta-analysis demonstrated that statin therapy was associated with improved survival rates and patency rates and with reduced cardiovascular or stroke morbidities in patients who underwent non-cardiac vascular surgeries.

Combined statin and angiotensin-converting enzyme (ACE) inhibitor treatment increases the lifespan of long-lived F1 male mice

Statins, such as simvastatin, and ACE inhibitors (ACEis), such as ramipril, are standard therapies for the prevention and treatment of cardiovascular diseases. These types of drugs are commonly administered together. More recently, angiotensin II type 1 receptor (AT1R) antagonists, such as candesartan cilexetil (candesartan), have been used in the place of, or in combination with, ACEis. Here, we investigated the effects of simvastatin and ramipril single and combination therapy, and candesartan treatment on the lifespan of isocalorically fed, long-lived, B6C3F1 mice. Males were used for their relative endocrine simplicity and to minimize animal usage. The drugs were administered daily in food. The simvastatin and ramipril combination therapy significantly increased the mean and median lifespan by 9 %. In contrast, simvastatin, ramipril, or candesartan monotherapy was ineffective. All groups consumed the same number of calories. Simvastatin, alone or administered with ramipril, decreased body weight without changing caloric consumption, suggesting it may alter energy utilization in mice. Combination therapy elevated serum triglyceride and glucose levels, consistent with altered energy homeostasis. Few significant or consistent differences were found in mortality-associated pathologies among the groups. Simvastatin treatment did not reduce normal serum cholesterol or lipid levels in these mice, suggesting that the longevity effects may stem from the pleiotropic, non-cholesterol-related, effects of statins. Together, the results suggest that statins and ACEis together may enhance mouse longevity. Statins and ACE inhibitors are generally well-tolerated, and in combination, they have been shown to increase the lifespan of normotensive, normocholesterolemic humans.

Effects of Atorvastatin Dose and Concomitant Use of Angiotensin-Converting Enzyme Inhibitors on Renal Function Changes over Time in Patients with Stable Coronary Artery Disease: A Prospective Observational Study

Angiotensin-converting enzyme inhibitors (ACEI) and statins are widely used in patients with coronary artery disease (CAD). Our aim was to compare changes in glomerular filtration rate (GFR) over time in subjects with stable CAD according to atorvastatin dose and concomitant use of ACEI. We studied 78 men with stable CAD referred for an elective coronary angiography who attained the then-current guideline-recommended target level of low-density lipoproteins (LDL) cholesterol below 2.5 mmol/L in a routine fasting lipid panel on admission and were receiving atorvastatin at a daily dose of 10-40 mg for ≥3 months preceding the index hospitalization. Due to an observational study design, atorvastatin dosage was not intentionally modified for other reasons. GFR was estimated during index hospitalization and at about one year after discharge from our center. Irrespective of ACEI use, a prevention of kidney function loss was observed only in those treated with the highest atorvastatin dose. In 38 subjects on ACEI, both of the higher atorvastatin doses were associated with increasing beneficial effects on GFR changes (mean ± SEM: -4.2 ± 2.4, 1.1 ± 1.6, 5.2 ± 2.4 mL/min per 1.73 m² for the 10-mg, 20-mg and 40-mg atorvastatin group, respectively, p = 0.02 by ANOVA; Spearman's rho = 0.50, p = 0.001 for trend). In sharp contrast, in 40 patients without ACEI, no significant trend effect was observed across increasing atorvastatin dosage (respective GFR changes: -1.3 ± 1.0, -4.7 ± 2.1, 4.8 ± 3.6 mL/min per 1.73 m², p = 0.02 by ANOVA; rho = 0.08, p = 0.6 for trend). The results were substantially unchanged after adjustment for baseline GFR or time-dependent variations of LDL cholesterol. Thus, concomitant ACEI use appears to facilitate the ability of increasing atorvastatin doses to beneficially modulate time-dependent changes in GFR in men with stable CAD.

Graz Critical Limb Ischemia Score: A Risk Score for Critical Limb Ischemia in Peripheral Arterial Occlusive Disease

Critical limb ischemia (CLI), a frequently encountered disorder, is associated with a high rate of limb amputation and mortality. To identify patients at high risk for CLI, we developed a simple risk score for peripheral arterial occlusive disease (PAOD).In our cross-sectional study, we first evaluated 1000 consecutive PAOD patients treated at our institution from 2005 to 2007, documenting clinical symptoms, comorbidities, and concomitant medication. We calculated odds ratios (OR) in a binary logistic regression model to find possible risk factors for CLI. We then verified the score in a second step that included the 1124 PAOD patients we treated between 2007 and 2011.In the first patient group, the greatest risk factors for CLI were age ≥75 years (OR 2.0), type 2 diabetes (OR 3.1), prior myocardial infarction (OR 2.5), and therapy with low molecular weight heparins (2.8). We scored 1 point for each of those conditions. One point was given for age between 65 and 75 years (OR 1.6) as well as for therapy with cardiac glycosides (OR 1.9) or loop diuretic therapy (OR 1.5). As statin therapy was protective for CLI with an OR of 0.5, we subtracted 1 point for those patients.In the second group, we could prove that frequency of CLI was significantly higher in patients with a high CLI score. The score correlated well with inflammatory parameters (c-reactive protein and fibrinogen). We were also able to define 3 different risk groups for low (score -1 to 1), intermediate (score 2-4), and high CLI risk (score >4).We developed a simple risk stratification scheme that is based on conditions that can be easily assessed from the medical history, without any laboratory parameters. This score should help to identify PAOD patients at high risk for CLI.

Variation of plantar pressure in Chinese diabetes mellitus

To investigate dynamic changes in plantar pressure in Chinese diabetes mellitus patients and to provide a basis for further preventing diabetic foot. This is a cross-sectional investigation including 649 Chinese diabetes mellitus patients (diabetes group) and 808 "normal" Chinese persons (nondiabetes group) with normal blood glucose levels. All the subjects provided a complete medical history and underwent a physical examination and a 75-g oral glucose tolerance test. All subjects walked barefoot with their usual gait, and their dynamic plantar forces were measured using the one-step method with a plantar pressure measurement instrument; 5 measurements were performed for each foot. No significant differences were found in age, height, body weight, or body mass index between the two groups. The fasting blood glucose levels, plantar contact time, maximum force, pressure-time integrals and force-time integrals in the diabetes group were significantly higher than those in the nondiabetes group (p < 0.05). However, the maximum pressure was significantly higher in the nondiabetes group than in the diabetes group (p < 0.05). No difference was found in the contact areas between the two groups (p > 0.05). The maximum plantar force distributions were essentially the same, with the highest force found for the medial heel, followed by the medial forefoot and the first toe. The peak plantar pressure was located at the medial forefoot for the nondiabetes group and at the hallucis for the diabetes group. In the diabetes group, the momentum in each plantar region was higher than that in the nondiabetes group; this difference was especially apparent in the heel, the lateral forefoot and the hallucis. The dynamic plantar pressures in diabetic patients differ from those in nondiabetic people with increased maximum force and pressure, a different distribution pattern and significantly increased momentum, which may lead to the formation of foot ulcers.