Meta-analysis of the effect of diabetes on restenosis rates among patients receiving coronary angioplasty stenting

Metal allergy and neurovascular stenting: A systematic review

BACKGROUND

Intracranial stents and flow diverters contain significant amounts of metals, notably nickel, which can cause allergic reactions in a considerable portion of the population. These allergic responses may lead to complications like in-stent stenosis (ISS) and TIA/Stroke in patients receiving stents or flow diverters for intracranial aneurysms.

METHODS

We conducted a systematic review of studies from inception until July 2023, which reported outcomes of patients with metal allergy undergoing neurovascular stenting. The skin patch test was used to group patients into those with positive, negative, or absent patch test results but with a known history of metal allergy.

RESULTS

Our review included seven studies with a total of 39 patients. Among them, 87% had a history of metal allergy before treatment. Most aneurysms (89%) were in the anterior circulation and the rest (11%) were in the posterior circulation. Skin patch tests were performed in 59% of patients, with 24% showing positive results and 33% negative. Incidental ISS was observed in 18% of patients, and the rate of TIA/Stroke was reported in 21%. The pooled rates of ISS and TIA/Stroke were higher in the first group (43% and 38%) compared to the second (18% and 9%) and third groups (15% and 15%), but these differences were not statistically significant.

CONCLUSIONS

The current neurosurgical literature does not provide a conclusive association between metal allergy and increased complications among patients undergoing neurovascular stenting. Further studies are necessary to gain a more comprehensive understanding of this topic.

Genetic Variants in PHACTR1 & LPL Mediate Restenosis Risk in Coronary Artery Patients

Background and Objective

Coronary artery disease (CAD) is a major cause of death worldwide. Revascularization via stent placement or coronary artery bypass grafting (CABG) are standard treatments for CAD. Despite a high success rate, these approaches are associated with long-term failure due to restenosis. Risk factors associated with restenosis were investigated using a case-control association study design.

Methods

Five thousand two hundred and forty-two patients were enrolled in this study and were assigned as follows: Stenosis Group: 3570 patients with CAD >50% without a prior stent or CABG (1394 genotyped), and Restenosis Group: 1672 patients with CAD >50% and prior stent deployment or CABG (705 genotyped). Binomial regression models were applied to investigate the association of restenosis with diabetes, hypertension, and dyslipidemia. The genetic association with restenosis was conducted using PLINK 1.9.

Results

Dyslipidemia is a major risk factor (Odds Ratio (OR) = 2.14, P-value <0.0001) for restenosis particularly among men (OR = 2.32, P < 0.0001), while type 2 diabetes (T2D) was associated with an increased risk of restenosis in women (OR = 1.36, P = 0.01). The rs9349379 (PHACTR1) and rs264 (LPL) were associated with an increased risk of restenosis in our patients. PHACTR1 variant was associated with increased risk of restenosis mainly in women and in diabetic patients, while the LPL variant was associated with increased risk of restenosis in men.

Conclusion

The rs9349379 in PHACTR1 gene is significantly associated with restenosis, this association is more pronounced in women and in diabetic patients. The rs264 in LPL gene was associated with increased risk of restenosis in male patients.

Donor Heterogeneity in the Human Macrophage Response to a Biomaterial under Hyperglycemia in vitro

Macrophages have a commanding role in scaffold-driven in situ tissue regeneration. Depending on their polarization state, macrophages mediate the formation and remodeling of new tissue by secreting growth factors and cytokines. Therefore, successful outcomes of material-driven in situ tissue vascular tissue engineering depends largely on the immuno-regenerative potential of the recipient. A large cohort of patients requiring vascular replacements suffers from systemic multifactorial diseases, like diabetes, which gives rise to a hyperglycemic and aggressive oxidative inflammatory environment that is hypothesized to hamper a well-balanced regenerative process. Here, we aimed to fundamentally explore the effects of hyperglycemia, as one of the hallmarks of diabetes, on the macrophage response to 3D electrospun synthetic biomaterials for in situ tissue engineering, in terms of inflammatory profile and tissue regenerative capacity. To simulate the early phases of the in situ regenerative cascade, we used a bottom-up in vitro approach. Primary human macrophages (n=8 donors) and (myo)fibroblasts in mono- or co-culture were seeded in 2D, as well as in a 3D electrospun resorbable polycaprolactone bisurea (PCL-BU) scaffold and exposed to normoglycemic (5.5 mM glucose), hyperglycemic (25 mM glucose) and osmotic control conditions (5.5 mM glucose, 19.5 mM mannitol). The results showed that macrophage polarization by biochemical stimuli was effective under all glycemic conditions and that the polarization states dictated expression of the receptors SCL2A1 (glucose transporter 1) and CD36 (fatty acid transporter). In 3D, the macrophage response to hyperglycemic conditions was strongly donor-dependent in terms of phenotype, cytokine secretion profile, and metabolic receptor expression. When co-cultured with (myo)fibroblasts, hyperglycemic conditions led to an increased expression of fibrogenic markers (ACTA2, COL1, COL3, IL-1β). Together, these findings show that the hyperglycemic and hyperosmotic conditions may indeed influence the process of macrophage-driven in situ tissue engineering, and that the extent of this is likely to be patient-specific.

Diabetes and restenosis

Restenosis, defined as the re-narrowing of an arterial lumen after revascularization, represents an increasingly important issue in clinical practice. Indeed, as the number of stent placements has risen to an estimate that exceeds 3 million annually worldwide, revascularization procedures have become much more common. Several investigators have demonstrated that vessels in patients with diabetes mellitus have an increased risk restenosis. Here we present a systematic overview of the effects of diabetes on in-stent restenosis. Current classification and updated epidemiology of restenosis are discussed, alongside the main mechanisms underlying the pathophysiology of this event. Then, we summarize the clinical presentation of restenosis, emphasizing the importance of glycemic control in diabetic patients. Indeed, in diabetic patients who underwent revascularization procedures a proper glycemic control remains imperative.

Frequency of recurrence of peripheral artery disease among angioplasty and stenting patients

Background

Peripheral artery disease (PAD) is a cardiovascular disease that is characterized by obstruction of peripheral artery. It is associated with comorbidities, reduced quality of life and mortality. The aim of this study was to determine the frequency of recurrence of PAD among patients who underwent angioplasty or stenting and associated risk factors.

Methods

In this retrospective study, all patients referred to the cardiovascular center of (XXX) with the diagnosis of lower extremity PAD were included. Patients’ demographic information, age, gender, smoking status, history of diabetes, history of hypertension, dyslipidemia, number of vessels, type of stent, recurrence of the disease, and size of the lesion were obtained from the hospital database. Endovascular revascularization therapy was either performed by angioplasty or stenting method. The data were analyzed by SPSS v21.

Results

Of 88 patients included in this study, 12.5% were reported with restenosis. Gender, age, size of the lesion, the status of smoking, history of hypertension, and dyslipidemia were not significantly associated with the recurrence of stenosis, p > 0.05. There was a significant relationship between the vessels involved and the type of revascularization method and the recurrence of the PAD.

Conclusion

Endovascular revascularization technique and type of vessel involved in PAD are significant factors contributing to restenosis in our population of study. However, further studies with a greater sample size are required in this area.

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Peripheral artery disease is a cardiovascular disease with obstruction of peripheral artery.

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It is associated with comorbidities, reduced quality of life and even mortality.

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Endovascular revascularization technique in PAD are significant factor in our study.

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However, further studies with greater sample size are required in this area.

Impact of anemia on in-stent restenosis after percutaneous coronary intervention

Background

Anemia is a common risk factor for post-percutaneous coronary intervention (PCI) adverse events; however, data on its association with in-stent restenosis (ISR) is limited.

Methods

538 patients who underwent PCI between January 2017 and September 2019 and follow-up angiography 9–12 months after the initial PCI were enrolled in this study. Baseline clinical and procedural characteristics were compared between the ISR and non-ISR groups, and independent predictors of ISR were determined using propensity score matching.

Results

The incidence of anemia was 53.5% in patients with ISR and 19.0% in those without ISR. Univariable logistic regression analyses showed that anemia (OR, 4.283; 95% CI, 1.949–9.410; P < 0.001), diabetes mellitus (OR, 2.588; 95% CI, 1.176–5.696; P = 0.018), chronic kidney disease (OR, 3.058; 95% CI, 1.289–7.252; P = 0.011), multiple stenting (OR, 2.592; 95% CI, 1.205–5.573; P = 0.015), bifurcation lesion (OR, 2.669; 95% CI, 1.236–5.763; P = 0.012), and calcification (OR, 3.529; 95% CI, 1.131–11.014; P = 0.030) were closely associated with ISR. Low-density lipoprotein cholesterol (LDL-c) levels and stent diameter were also significantly linked to ISR, as was anemia (P = 0.009) after propensity score matching.

Conclusion

Anemia is closely associated with post-PCI ISR, and patients with lower hemoglobin levels are at a higher risk of ISR.

Immuno-regenerative biomaterials for in situ cardiovascular tissue engineering - Do patient characteristics warrant precision engineering?

In situ tissue engineering using bioresorbable material implants - or scaffolds - that harness the patient's immune response while guiding neotissue formation at the site of implantation is emerging as a novel therapy to regenerate human tissues. For the cardiovascular system, the use of such implants, like blood vessels and heart valves, is gradually entering the stage of clinical translation. This opens up the question if and to what extent patient characteristics influence tissue outcomes, necessitating the precision engineering of scaffolds to guide patient-specific neo-tissue formation. Because of the current scarcity of human in vivo data, herein we review and evaluate in vitro and preclinical investigations to predict the potential role of patient-specific parameters like sex, age, ethnicity, hemodynamics, and a multifactorial disease profile, with special emphasis on their contribution to the inflammation-driven processes of in situ tissue engineering. We conclude that patient-specific conditions have a strong impact on key aspects of in situ cardiovascular tissue engineering, including inflammation, hemodynamic conditions, scaffold resorption, and tissue remodeling capacity, suggesting that a tailored approach may be required to engineer immuno-regenerative biomaterials for safe and predictive clinical applicability.

Some Perspectives on Hypersensitivity to Coronary Stents

The development of coronary stents has represented a revolution in the treatment of coronary heart disease. Beyond their many advantages, stents also have their limitations and complications. Allergic reactions to coronary stents are more common than acknowledged. These stented patients are exposed to foreign substances inserted in direct contact with the coronary intima. Hypersensitivity to stent components and drugs prescribed after stent insertion together with any environmental exposure seem to contribute to these adverse reactions. Patients can present to the hospital with a wide range of symptoms and multiple complications, the most important ones being instent restenosis and stent thrombosis. Although not very common (and not always easy to identify), allergic reactions after coronary or peripheral stents should be taken into account. Careful selection of patients (for elective stent implantation) depending on the propensity to allergies, although hard to achieve, represents a key factor in reducing the number of these complications.

Diabetic patients who present with ST-elevation myocardial infarction

BACKGROUND

The long-term outcomes of diabetic patients presenting with ST-segment elevation myocardial infarction (STEMI) in contemporary practice have received limited study.

METHODS

We evaluated the clinical characteristics and outcomes of STEMI patients with and without diabetes in a large regional STEMI program designed to facilitate timely primary percutaneous coronary intervention (PCI) (Minneapolis Heart Institute at Abbott Northwestern Hospital, Minneapolis, MN). The primary and secondary outcome measures were in-hospital mortality, 1-year major adverse cardiovascular events (MACE) (stroke, myocardial infarction, unplanned PCI or coronary artery bypass graft [CABG] surgery, and all-cause mortality), and 5-year mortality.

RESULTS

Of the 6292 patients included, 1158 (18.4%) had Diabetes Mellitus (DM) (95.3% Type II, 4.7% Type I). Patients with DM were older (mean age 66 vs. 62.8 years, p < 0.01), had more co-morbidities and were more likely to receive medical therapy without reperfusion (13% vs. 10%, p = 0.003). Patients with DM had higher in-hospital (8% vs. 5%, p = 0.001), 1-year (8% vs. 4%, p < 0.001) and 5-year mortality (16% vs. 9%, p < 0.001) compared to non-diabetics. On Cox proportional hazards analysis, DM was independently associated with worse mortality (hazard ratio: 1.70, 95% confidence interval (CI): 1.32-2.19, p < 0.001) and MACE [HR: 1.63 (95% (CI)): 1.28-2.08, p < 0.001].

CONCLUSIONS

Despite advancements in medical therapy and revascularization strategies for STEMI, DM remains independently associated with higher short- and long-term morbidity and mortality in contemporary practice.

Primary Percutaneous Coronary Intervention in Patients With Type 2 Diabetes With Late/Very Late Stent Thrombosis and de novo Lesions: A Single-Center Observational Cohort Study of Clinical Outcomes and Influencing Factors

Background: This study compared differences in the risk factors and clinical outcomes of primary percutaneous coronary intervention (PCI) in type 2 diabetes mellitus (DM) and non-DM patients with de novo lesions (DNLs) and late or very late stent thrombosis (LST/VLST).

Methods: We used angiography to screen 4,151 patients with acute coronary syndrome for DNL and LST/VLST lesions. Overall, 3,941 patients were included in the analysis and were allocated to the DM (n = 1,286) or non-DM (n = 2,665) group at admission. The primary endpoint was a composite of major adverse cardiovascular events (MACEs), defined as death, myocardial infarction, revascularization, and ischemic stroke, within a median follow-up period of 698 days.

Results: In the group with a total white blood cell count >10 × 10⁹/L (P = 0.004), a neutral granular cell count >7 × 10⁹/L (P = 0.030), and neutrophil–lymphocyte ratio >1.5 (P = 0.041), revascularization was better for DNL than for LST/VLST lesions. Among DM patients with DNLs, each unit increase in age was associated with a 53.6% increase in the risk of MACEs [hazard ratio (HR): 1.536, 95% confidence interval (CI), 1.300–1.815, P < 0.0001]. Older age (≥65 years) was associated with a significantly greater risk of MACEs (P < 0.0001). Furthermore, each standard deviation (SD) increase in the level of peak white blood cell counts was associated with a 50.1% increase in the risk of MACEs (HR, 1.501; 95% CI, 1.208–1.864; P = 0.0002). When stratifying the DM population with DNLs according to the D-dimer baseline and peak levels <0.5 vs. ≥0.5 mg/L, the high D-dimer group at baseline had a 2.066-fold higher risk of MACEs (P < 0.0001), and the high peak level D-dimer group had a 1.877-fold higher risk of MACEs (P = 0.001) compared to the low-level groups. Among DM patients with LST/VLST, each unit increase in age was associated with a 75.9% increase in the risk of MACEs (HR: 1.759, 95% CI, 1.052–2.940, P = 0.032). Furthermore, for each SD increase in the peak D-dimer level, the risk of MACEs increased by 59.7% (HR, 1.597; 95% CI, 1.110–2.295; P = 0.041).

Conclusion: Following successful primary PCI, the measurement of baseline and peak D-dimer values may help identify individuals at high cardiovascular risk. This suggests a potential benefit of lowering D-dimer levels among T2DM patients with DNL. Furthermore, age and the peak D-dimer values may facilitate the risk stratification of T2DM patients with LST/VLST.

Risk prediction of in-stent restenosis among patients with coronary drug-eluting stents: current clinical approaches and challenges

Introduction: In-stent restenosis (ISR) has been one of the biggest limitations to the success of percutaneous coronary intervention for the treatment of coronary artery disease (CAD). The introduction of drug-eluting stent (DES) was a revolution in the treatment of CAD because these devices drastically reduced ISR to very low levels (<5%). Subsequently, newer generation DES treatments have overcome the drawbacks of first-generation DES, i.e. delayed endothelialization, and late stent thrombosis. However, the issue of late ISR, including neoatherosclerosis after DES implantation especially in high-risk patients and complex lesions, still exists as a challenge to be overcome.Areas covered: We discuss the mechanisms of ISR development including neoatherosclerosis, past and current clinical status of ISR, and methods to predict and overcome this issue from pathological and clinical points of view.Expert opinion: The initial drawbacks of first-generation DES, such as delayed endothelial healing and subsequent risk of late stent thrombosis, have been improved upon by the current generation DES. To achieve better long-term clinical outcomes, further titration of drug-release and polymer degradation profile, strut thickness as well as material innovation are needed.

Visit-to-visit HbA1c variability is associated with in-stent restenosis in patients with type 2 diabetes after percutaneous coronary intervention

Background

Patients with type 2 diabetes are under substantially higher risk of in-stent restenosis (ISR) after coronary stent implantation. We sought to investigate whether visit-to-visit HbA_1c variability is a potential predictor of ISR in diabetic patients after stent implantation.

Methods

We consecutively enrolled type 2 diabetic patients who underwent successful elective percutaneous coronary intervention and performed follow-up coronary angiography after around 12 months. The incidence of ISR and its relationship with visit-to-visit HbA_1c variability, expressed as coefficient of variation (CV), standard deviation (SD) and variability independent of the mean (VIM), were studied. Multivariable Cox proportional hazards models were constructed to analyze the predictive value of HbA_1c variability for ISR.

Results

From September 2014 to July 2018 in Ruijin Hospital, a total of 420 diabetic patients (688 lesions) after stent implantation were included in the final analysis. During a mean follow-up of 12.8 ± 1.3 months, the incidence of ISR was 8.6%, which was significantly increased in patients with higher CV of HbA_1c (P = 0.001). The mean diameter stenosis (DS), net luminal loss and net luminal gain were 22.9 ± 16.8%, 0.42 ± 0.88 mm and 1.66 ± 0.83 mm, respectively. Greater DS was observed in subjects with higher tertiles of CV of HbA_1c (P < 0.001), and this trend was more prominent in patients with optimal glycemic control (HbA_1c ≤ 7%) in the baseline. In multivariate analysis, HbA_1c variability was independently associated with incidence of ISR after adjustment for traditional risk factors and mean HbA_1c (HR: 3.00 [95% CI 1.14–7.92] for highest vs. lowest tertile). Inclusion of CV of HbA_1c led to a better risk stratification accuracy. Assessing HbA_1c variability by SD or VIM yielded similar findings.

Conclusions

This study suggests that visit-to-visit HbA_1c variability is an independent predictor of incidence of ISR in patients with type 2 diabetes after stent implantation.

Trial registration NCT02089360: NCT

Comparison of Neointimal Response between Durable-Polymer Everolimus-Eluting Stent and Bioabsorbable-Polymer Everolimus-Eluting Stent for Severely Calcified Lesions Requiring Rotational Atherectomy

Clinical outcomes after percutaneous coronary intervention (PCI) for severely calcified lesions remain poor. The purpose of this study was to investigate the neointimal response after everolimus-eluting stents (EES) for severely calcified lesions treated with rotational atherectomy (RA) using optical coherence tomography (OCT).We retrospectively analyzed 34 lesions in which PCI was performed with EES deployment following RA and OCT was performed immediately after PCI and at follow-up (nine months). The EES was either durable-polymer (DP) EES (22 lesions) or bioabsorbable polymer (BP) -EES (12 lesions). Strut coverage and malapposition were evaluated at 1-mm intervals of cross-section (CS) by serial OCT analysis. Malapposed strut was defined as having the distance from luminal border > 100 μm.A total of 11,823 struts immediately after PCI and 11,720 struts at follow-up were analyzed. Immediately after PCI, the strut-level analysis showed no significant differences in the percentage of malapposed struts between the DP-EES group and the BP-EES group. At follow-up, the BP-EES group showed a more prevalent covered strut compared with the DP-EES group (strut-level analysis: 95% versus 97%, P = 0.045; CS-level analysis: 97% versus 100%, P < 0.01; lesion-level analysis: 27% versus 83%, P < 0.01, respectively).In severely calcified lesions requiring RA, the BP-EES group achieved better neointimal coverage than the DP-EES group at nine months. Additional prospective studies are needed.

Comprehensive analysis of predictive factors for rapid angiographic stenotic progression and restenosis risk in coronary artery disease patients underwent percutaneous coronary intervention with drug-eluting stents implantation

BACKGROUND

This study aimed to explore the correlation of baseline, procedural, and postprocedure characteristics with the risk of rapid angiographic stenotic progression (RASP) and restenosis in coronary artery disease (CAD) patients after percutaneous coronary intervention (PCI) with drug-eluting stents implantation.

METHODS

Two hundred fourteen CAD patients underwent PCI with drug-eluting stents implantation were consecutively enrolled. Baseline, procedural, and postprocedure characteristics of patients were collected for analysis. Coronary angiography was performed to evaluate coronary stenosis before PCI and at 12 months after PCI. RASP of nontarget lesions and restenosis of stent-implanted target lesions were then assessed.

RESULTS

37.8% CAD patients occurred RASP at 12 months after PCI and compared to non-RASP group, RASP group presented with increased diabetes mellitus (DM) complication, higher concentration of serum uric acid (SUA), cardiac troponin I, N-terminal probrain natriuretic peptide, and high sensitive C-reactive protein (hs-CRP) as well as elevated occurrence of multivessel artery lesions. In addition, DM, SUA, hs-CRP, and multivessel artery lesions independently predicted high RASP risk. For restenosis, 21.0% patients occurred restenosis at 12 months after PCI, and patients in restenosis group presented with increased hypertension and DM occurrence, higher concentrations of SUA, LDL-C, and hs-CRP, as well as longer target lesion and length of stent in surgery compared to nonrestenosis group. Also, DM, SUA, LDL-C, hs-CRP, and length of target lesion independently predicted increased restenosis risk.

CONCLUSION

Diabetes mellitus, SUA, and hs-CRP are potential predictive factors for increased risk of both RASP and restenosis in CAD patients underwent PCI and drug-eluting stents implantation.

Trends in diagnosis-specific work disability before and after ischaemic heart disease: a nationwide population-based cohort study in Sweden

OBJECTIVES

We examined trends of diagnosis-specific work disability before and after ischaemic heart disease (IHD).

DESIGN

Participants were followed 4 years before and 4 years after an IHD event for diagnosis-specific work disability (sickness absence and disability pension).

SETTING AND PARTICIPANTS

A Swedish population-based cohort study using register data on all individuals aged 25-60 years, living in Sweden, and who suffered their first IHD event in 2006-2008 (n=23 971) was conducted.

RESULTS

Before the event, the most common diagnoses of work disability were musculoskeletal disorders (21 annual days for men and 44 for women) and mental disorders (19 men and 31 for women). After multivariable adjustments, we observed a fivefold increase (from 12 to 60 days) in work disability due to diseases of the circulatory system in the first postevent year compared with the last pre-event year among men. Among women, the corresponding increase was fourfold (from 14 to 62 days). By the second postevent year, the number of work disability days decreased significantly compared with the first postevent year among both sexes (to 19 days among men and 23 days among women). Among women, mean days of work disability due to diseases of the circulatory system remained at a higher level than among men during the postevent years. Work disability risk after versus before an IHD event was slightly higher among men (rate ratio (RR) 2.49; 95% CI 2.36 to 2.62) than among women (RR 2.29, 95% CI 2.12 to 2.49). When pre-event long-term work disability was excluded, diseases of the circulatory system were the most prevalent diagnosis for work disability after an IHD event among both men and women.

CONCLUSIONS

An IHD event was strongly associated with an increase in work disability due to diseases of the circulatory system, especially among men and particularly in the first postevent year.

Outcomes of Coronary Artery Bypass Graft Surgery Versus Percutaneous Coronary Intervention in Patients Aged 18-45 Years with Diabetes Mellitus

BACKGROUND

Debate on treatment for young patients with coronary artery disease still exists. This study aimed to investigate the intermediate- and long-term outcomes between coronary artery bypass grafting (CABG) and percutaneous coronary intervention (PCI) in patients aged 18-45 years with diabetes mellitus (DM).

METHODS

Between January 2006 and March 2016, a total of 2018 DM patients aged 18-45 years including 517 cases of CABG and 1501 cases of PCI were enrolled in the study. Using propensity score matching (PSM), 406 patients were matched from each group. The intermediate- and long-term data were collected. The primary end point of this study was long-term death. The secondary end points included long-term major adverse cardiovascular and cerebrovascular events (MACCEs), stroke, angina, myocardial infarction (MI), and repeat revascularization.

RESULTS

Before PSM, the in-hospital mortality was 1.2% in the CABG group and 0.1% in the PCI group, with statistically significant difference (P < 0.0001). The 10-year follow-up outcomes including long-term survival rate and freedom from MACCEs were better in the CABG group than those in the PCI group (97.3% vs. 94.5%, P = 0.0072; 93.2% vs. 86.3%, P < 0.0001), but CABG group was associated with lower freedom from stoke compared to PCI group (94.2% vs. 97.5%, P = 0.0059). After propensity score-matched analysis, these findings at 10-year follow-up were also confirmed. Freedom from MACCEs was higher in CABG group compared to PCI group, but no significant difference was observed (93.1% vs. 89.2%, P = 0.0720). The freedom from recurrent MI was significantly higher in CABG patients compared with PCI patients (95.6% vs. 92.5%, P = 0.0260). Furthermore, CABG was associated with a higher rate of long-term survival rate than PCI (97.5% vs. 94.6%, P = 0.0403). There was no significant difference in the freedom from stroke between CABG and PCI groups (95.3% vs. 97.3%, P = 0.9385). The hospital cost was greater for CABG (13,936 ± 4480 US dollars vs. 10,926 ± 7376 US dollars, P < 0.0001).

CONCLUSIONS

In DM patients aged 18-45 years, the cumulative survival rate, and freedom from MI and repeat revascularization for CABG were superior to those of PCI. However, a better trend to avoid stroke was observed with PCI.

Impact of free thyroxine levels and other clinical factors on bare metal stent restenosis

OBJECTIVE

Thyroid hormones have both direct and indirect effects on thermogenesis such as modulating vascular smooth muscle cell proliferation. However, the influence of more subtle changes in thyroid hormones on coronary atherosclerosis remains a matter of speculation. Smooth muscle cells play a crucial role in the pathogenesis of in-stent restenosis (ISR). However, the relationship between free thyroxine (fT4) and ISR has not been studied. In the present study, we aimed to assess the role of preprocedural serum fT4 level on the development of ISR in patients undergoing coronary bare metal stent (BMS) implantation.

MATERIALS AND METHODS

We enrolled and analyzed clinical, biochemical, and angiographic data from 705 consecutive patients without a history of primary thyroid disease [mean age 60.3 ± 9.3 years, 505 (72%) male]; all patients had undergone BMS implantation and further control coronary angiography owing to stable or unstable angina pectoris. Patients were divided into 3 tertiles based on preprocedural serum fT4 levels.

RESULTS

ISR was observed in 53 (23%) patients in the lowest tertile, 82 (35%) patients in the second tertile, and 107 (46%) patients in the highest fT4 tertile (p < 0.001). Using multiple logistic regression analysis, five characteristics emerged as independent predictors of ISR: diabetes mellitus, smoking, HDL-cholesterol, stent length, and preprocedural serum fT4 level. In receiver operating characteristics curve analysis, fT4 level > 1.23 mg/dL had 70% sensitivity and 73% specificity (AUC: 0.75, p < 0.001) in predicting ISR.

CONCLUSION

Higher preprocedural serum fT4 is a powerful and independent predictor of BMS restenosis in patients with stable and unstable angina pectoris.

Five-year clinical outcomes of drug-eluting stents according to on-label and off-label use

BACKGROUND/AIMS

To compare the clinical outcomes of 'on-label' and 'off-label' drug-eluting stents (DESs) over a 5-year follow-up period.

METHODS

A total of 929 patients that underwent percutaneous coronary intervention with DESs were enrolled. Patients were divided into two groups according to on-label (n = 449) and off-label (n = 480) indications. Off-label use was defined as implantation of DESs for acute myocardial infarction (MI), very small vessel, a long stenotic lesion, chronic total occlusion, a bifurcation lesion, an ostial lesion, left main coronary artery disease, multivessel disease, a saphenous vein graft lesion, and a lesion with thrombus. Endpoints were composite of major adverse cardiac events (MACEs), which included all-cause death, ischemic-driven target vessel revascularization (Id-TVR), MI, and stent thrombosis (ST). Clinical outcomes in the two groups were compared for up to 5 years postimplantation.

RESULTS

At 1 year postimplantation, the off-label group had higher incidences of total MACEs (8.2% vs. 3.7%, p = 0.005), Id-TVR (5.0% vs. 1.6%, p = 0.004), and ST (1.7% vs. 0.3%, p = 0.042), and at 5 years postimplantation, the off-label group continued to have higher incidences of total MACEs (17.5% vs. 9.4%, p < 0.001), Id-TVR (13.1% vs. 5.8%, p = 0.024), and ST (2.1% vs. 0.3%, p = 0.021). Multivessel disease and diabetes were found to be independent risk factors of MACE in patients with an off-label indication.

CONCLUSIONS

Patients treated with an on-label DES had better long-term clinical outcomes than those treated with an off-label DES.

Revascularization in patients with diabetes: PCI or CABG or none at all

Patients with diabetes have a high incidence of coronary artery disease, with particularly high rates of acute coronary syndromes and mortality. Revascularization by coronary artery bypass grafting was found to be effective in reducing angina and mortality in patients with extensive coronary artery disease over 30 years ago. Percutaneous coronary intervention, particularly with drug-eluting stents, has more recently been demonstrated to reduce recurrent angina and improve quality of life in diabetic patients with less extensive coronary artery disease. Most recently, coronary artery bypass grafting has been shown to be superior to percutaneous coronary intervention in improving mortality in patients with diabetes and three-vessel coronary artery disease who are not at high surgical risk. The role of coronary artery bypass grafting vs. percutaneous coronary intervention in patients who have less extensive coronary artery disease and/or higher surgical risk has not been fully elucidated. Newer treatment strategies, such as percutaneous coronary intervention with second-generation drug-eluting stents, use of fractional flow reserve guidance, or hybrid revascularization combining minimally invasive coronary artery bypass grafting with percutaneous coronary intervention, may result in further improvements in outcomes in patients with diabetes and coronary artery disease.

Alagebrium inhibits neointimal hyperplasia and restores distributions of wall shear stress by reducing downstream vascular resistance in obese and diabetic rats

Mechanisms of restenosis in type 2 diabetes mellitus (T2DM) are incompletely elucidated, but advanced glycation end-product (AGE)-induced vascular remodeling likely contributes. We tested the hypothesis that AGE-related collagen cross-linking (ARCC) leads to increased downstream vascular resistance and altered in-stent hemodynamics, thereby promoting neointimal hyperplasia (NH) in T2DM. We proposed that decreasing ARCC with ALT-711 (Alagebrium) would mitigate this response. Abdominal aortic stents were implanted in Zucker lean (ZL), obese (ZO), and diabetic (ZD) rats. Blood flow, vessel diameter, and wall shear stress (WSS) were calculated after 21 days, and NH was quantified. Arterial segments (aorta, carotid, iliac, femoral, and arterioles) were harvested to detect ARCC and protein expression, including transforming growth factor-β (TGF-β) and receptor for AGEs (RAGE). Downstream resistance was elevated (60%), whereas flow and WSS were significantly decreased (44% and 56%) in ZD vs. ZL rats. NH was increased in ZO but not ZD rats. ALT-711 reduced ARCC and resistance (46%) in ZD rats while decreasing NH and producing similar in-stent WSS across groups. No consistent differences in RAGE or TGF-β expression were observed in arterial segments. ALT-711 modified lectin-type oxidized LDL receptor 1 but not RAGE expression by cells on decellularized matrices. In conclusion, ALT-711 decreased ARCC, increased in-stent flow rate, and reduced NH in ZO and ZD rats through RAGE-independent pathways. The study supports an important role for AGE-induced remodeling within and downstream of stent implantation to promote enhanced NH in T2DM.

Association of inflammatory markers and poor outcome in diabetic patients presenting with ST segment elevation myocardial infarction

OBJECTIVE

Carbohydrate metabolism disorders (CMD) significantly impact the development and progression of all forms of ischemic heart disease, and inflammation is regarded as a general pathogenetic link between CMD and ischemic heart disease.

METHODS

A total of 601 patients with ST segment elevation myocardial infarction (MI) (STEMI), admitted within 24 hours from the onset of symptoms during 1 year, were included in this registry study. The blood levels of inflammation markers were measured at days 10-14 with further follow up at 1 year.

RESULTS

The analysis of acute-phase percutaneous coronary intervention impact on the 1-year outcomes showed that endovascular revascularization significantly improved the 1-year prognosis of STEMI patients both with and without CMD. The analysis of inflammation markers showed significantly higher levels of interleukin (IL)-6 and sCD40L in MI patients with diabetes mellitus, and impaired glucose tolerance. Additionally, the patients with impaired glucose tolerance had significantly higher IL-12 levels. In the diabetic MI patients, the odds ratio of a poor 1-year outcome was high for patients with a high Killip classification of acute heart failure upon admission.

CONCLUSION

Persistent inflammation in STEMI patients with CMD undergoing percutaneous coronary intervention might be responsible for vascular complications within 1 year after MI. Comorbid diabetes mellitus or impaired glucose tolerance can amplify the significance of the inflammatory response for the development of adverse 1-year outcomes.

Coronary artery bypass grafting versus drug-eluting stents in patients with severe coronary artery disease and diabetes mellitus: systematic review and meta-analysis

BACKGROUND

A comprehensive meta-analysis was performed to evaluate the comparative benefits of coronary artery bypass grafting (CABG) versus drug-eluting stents (DES) in patients with diabetes mellitus and severe coronary artery disease (CAD).

METHODS

A comprehensive literature search of PubMed, Embase, and ScienceDirect was undertaken. References cited with the papers were also checked to identify relevant articles.

RESULTS

In all, four randomized controlled trials, two prospective registries, and 11 retrospective studies were identified for review. Pooled analysis demonstrated that DES was associated with lower all-cause mortality at Day 30. However, there was no significant difference between CABG and DES in mortality at 12 months and at maximum follow-up. Furthermore, DES was associated with lower overall and major adverse cardiac and cerebrovascular events (MACCE)-free survival, as well as a higher incidence of myocardial infarction and repeat revascularization. In contrast, CABG was associated with an increased risk of stroke.

CONCLUSIONS

For patients with diabetes mellitus and severe CAD, CABG is superior to DES in that it significantly improves overall and MACCE-free survival and reduces the incidence of myocardial infarction and repeat revascularization in the long term, although it is associated with greater perioperative risk and a higher incidence of stroke. Therefore, CABG should remain the gold standard for these patients.

Stratification of coronary artery disease patients for revascularization procedure based on estimating adverse effects

Background

Percutaneous coronary intervention (PCI) is the most commonly performed treatment for coronary atherosclerosis. It is associated with a higher incidence of repeat revascularization procedures compared to coronary artery bypass grafting surgery. Recent results indicate that PCI is only cost-effective for a subset of patients. Estimating risks of treatment options would be an effort toward personalized treatment strategy for coronary atherosclerosis.

Methods

In this paper, we propose to model clinical knowledge about the treatment of coronary atherosclerosis to identify patient-subgroup-specific classifiers to predict the risk of adverse events of different treatment options. We constructed one model for each patient subgroup to account for subgroup-specific interpretation and availability of features and hierarchically aggregated these models to cover the entire data. In addition, we deviated from the current clinical workflow only for patients with high probability of benefiting from an alternative treatment, as suggested by this model. Consequently, we devised a two-stage test with optimized negative and positive predictive values as the main indicators of performance. Our analysis was based on 2,377 patients that underwent PCI. Performance was compared with a conventional classification model and the existing clinical practice by estimating effectiveness, safety, and costs for different endpoints (6 month angiographic restenosis, 12 and 36 month hazardous events).

Results

Compared to the current clinical practice, the proposed method achieved an estimated reduction in adverse effects by 25.0% (95% CI, 17.8 to 30.2) for hazardous events at 36 months and 31.2% (95% CI, 25.4 to 39.0) for hazardous events at 12 months. Estimated total savings per patient amounted to $693 and $794 at 12 and 36 months, respectively. The proposed subgroup-specific method outperformed conventional population wide regression: The median area under the receiver operating characteristic curve increased from 0.57 to 0.61 for prediction of angiographic restenosis and from 0.76 to 0.85 for prediction of hazardous events.

Conclusions

The results of this study demonstrated the efficacy of deployment of bare-metal stents and coronary artery bypass grafting surgery for subsets of patients. This is one effort towards development of personalized treatment strategies for patients with coronary atherosclerosis that could significantly impact associated treatment costs.

Electronic supplementary material

The online version of this article (doi:10.1186/s12911-015-0131-0) contains supplementary material, which is available to authorized users.

Effect of metabolic syndrome on the response to arterial injury

BACKGROUND

Metabolic syndrome is now an epidemic in the United States population. Intimal hyperplasia remains the principal lesion in the development of restenosis after vessel wall injury. The aim of this study is to characterize the changes induced in wall morphology in the developing intimal hyperplasia within a murine model in the presence of diabetes (type 1) and metabolic syndrome.

METHODS

Control (wild type B6), Non Obese Diabetic, and metabolic syndrome (RCS-10) mice were used. The murine femoral wire injury model was used in which a micro wire is passed through a branch of the femoral and used to denude the common femoral and iliac arteries. Specimens were perfusion fixed and sections were stained with hematoxylin and eosin and Movat stains such that dimensional and compositional morphometry could be performed using an ImagePro system. Additional stains for proliferation and apoptosis were used.

RESULTS

In control mice, the injured femoral arteries develop intimal hyperplasia, which is maximal at 28 d and remains stable to day 56. Sham-operated vessels do not produce such a response. In diabetic mice, the intimal response increased 5-fold with a 2-fold increase in proteoglycan deposition, whereas in the metabolic syndrome mice there was a 6-fold increase in the intimal response and a similar increase in proteoglycan deposition. Collagen deposition was different with a 22-fold increase over control in collagen deposition in diabetes and a 100-fold increase over control in collagen deposition in metabolic syndrome as compared with the control injury mice. Maximal vascular smooth muscle cell (VSMC) proliferation was decreased in both diabetes and metabolic syndrome compared with controls, whereas early cell apoptosis in both diabetes and metabolic syndrome was sustained over a longer period of time compared with wild-type mice.

CONCLUSIONS

These data demonstrate that development of intimal hyperplasia is markedly different in diabetes and metabolic syndrome compared with controls, with an increase in collagen deposition, a reduction in VSMC proliferation, and an increase in early VSMC apoptosis. These findings suggest that preventative strategies against restenosis must be tailored for the diabetic and metabolic syndrome patients.

Sex differences in type 2 diabetes: focus on disease course and outcomes

BACKGROUND

Women with type 2 diabetes (T2D) are less likely to reach the goals for hemoglobin A1c compared with men, and have higher all-cause mortality. The risk of cardiovascular disease is elevated among both men and women with T2D, however, the risk has declined among men over recent years while it remains stationary in women. Reasons for these sex differences remain unclear, and guidelines for diabetes treatment do not differentiate between sexes. Possible causes for varying outcome include differences in physiology, treatment response, and psychological factors. This review briefly outlines sex differences in hormonal pathophysiology, and thereafter summarizes the literature to date on sex differences in disease course and outcome.

METHODS

Systematic searches were performed on PubMed using "sex", "gender", and various glucose-lowering therapies as keywords. Earlier reviews are summarized and results from individual studies are reported. Reference lists from studies were used to augment the search.

RESULTS

There is an increased risk of missing the diagnosis of T2D when screening women with only fasting plasma glucose instead of with an oral glucose tolerance test. The impact of various risk factors for complications may differ by sex. Efficacy and side effects of some glucose-lowering drugs differ between men and women. Men with T2D appear to suffer more microvascular complications, while women have higher morbidity and mortality in cardiovascular disease and also fare worse psychologically.

CONCLUSION

Few studies to date have focused on sex differences in T2D. Several questions demand further study, such as whether risk factors and treatment guidelines should be sex-specific. There is a need for clinical trials designed specifically to evaluate sex differences in efficacy and outcome of the available treatments.

Computational Fluid Dynamics Evaluation of Equivalency in Hemodynamic Alterations Between Driver, Integrity, and Similar Stents Implanted Into an Idealized Coronary Artery

We tested the hypothesis that a slight modification in fabrication from the Driver to the Integrity stent (Medtronic) results in nearly equivalent distributions of wall shear stress (WSS) and mean exposure time (MET), reflective of flow stagnation, and that these differences are considerably less than the Multi-Link Vision (Abbott Vascular) or BX Velocity (Cordis) bare metal stents when evaluated by computational fluid dynamics (CFD). Arteries were modeled as idealized straight rigid vessels without lesions. Two vessel diameters (2.25 and 3.0 mm) were studied for each stent and 2.75 mm diameter Integrity stents were also modeled to quantify the impact from best- and worst-case orientations of the stent struts relative to the primary blood flow direction. All stents were 18 mm in length and over-deployed by 10%. The results indicated that, regardless of diameter, the BX Velocity stents had the greatest percentage of the vessel exposed to adverse WSS followed by the Vision, Integrity, and Driver stents. In general, when strut thickness and stent:lumen ratio are similar, the orientation of struts is a determining factor for deleterious flow patterns. For a given stent, the number of struts was a larger determinant of adverse WSS and MET than strut orientation, suggesting that favorable blood flow patterns can be achieved by limiting struts to those providing adequate scaffolding. In conclusion, the Driver and Integrity stents both limit their number of linkages to those which provide adequate scaffolding while also maintaining similar strut thickness and stent:lumen ratios. The Integrity stent also imparts a slight helical velocity component. The modest difference in the fabrication approach between the Driver and Integrity stents is, therefore, not hemodynamically substantial in this idealized analysis, particularly relative to potentially adverse flow conditions introduced by the other stents modeled. This data was used in conjunction with associated regulatory filings and submitted to the FDA as part of the documents facilitating the recent approval for sale of the Resolute Integrity stent in the United States.

A comparative study of restenosis rates in bare metal and drug-eluting stents

BACKGROUND

Various studies have been performed throughout the world on the rate of restenosis using bare metal stents (BMS) and drug-eluting stents (DES). The prohibitive costs associated with DES generally dictate the type of stent used, especially in developing countries. Therefore, there was a need for a study to assess the effect of various risk factors on restenosis in BMS and DES in the Indian context. A study was performed in the premier institution of the Indian Armed Forces, the Army Hospital (Research and Referral), New Delhi, India, under the aegis of the Indian Council of Medical Research (New Delhi). The profile of patients in the armed forces is inherently diverse in terms of demography, ethnicity, genetics, etc, which reflects the diverse and varied nature of the population in India.

METHODS AND RESULTS

A total of 130 patients were included in the present study. Follow-up after stent implantation was scheduled for six to nine months following the procedure to assess symptoms, drug compliance, and treadmill test and coronary angiography results, and to ascertain the incidence of restenosis. However, only 80 patients returned for follow-up and, therefore, the final analysis was based on these patients. They were segregated into BMS (n=41) and DES (n=39) groups. Restenosis occurred in 29 patients (36.3%). Nine of 39 patients with DES (23.1%) and 20 of 41 patients with BMS (48.8%) developed restenosis. There was a statistically significant relationship between restenosis and female sex, clinical presentation before intervention and at the time of follow-up evaluation (unstable angina), hypertension, positive stress test and compliance with medical therapy (P<0.05). No statistically significant relationship was observed between restenosis and age, diabetes, smoking, obesity and diet (P>0.05).

CONCLUSIONS

DES appear to reduce the restenosis rate and clinical end points, and appear to be more cost effective than BMS. Patient-related factors (eg, sex, hypertension and unstable angina) are important variables that affect the restenosis rate. Noninvasive stress testing had high positive and negative predictive values. Therefore, based on the present study, noninvasive stress testing is suggested before routine angiography at follow-up, which will reduce the need for repeat coronary angiography.

Role of S-1-P receptors and human vascular smooth muscle cell migration in diabetes and metabolic syndrome

BACKGROUND

Sphingosine-1-phosphate (S-1-P) is a bioactive sphingolipid released from activated platelets that stimulates migration of vascular smooth muscle cells (VSMC) in vitro. S-1-P is associated with oxidized low-density lipoprotein (oxLDL) and is important in vessel remodeling. S-1-P will activate multiple G protein-coupled receptors (S-1-PR 1 to 5), which can regulate multiple cellular functions, including cell migration. The aim of this study is to examine the role of S-1-PR signaling during smooth muscle cell migration in response to S-1-P.

METHODS

Human VSMCs were cultured in vitro. Expression of S-1-PR 1 to 5 was determined in conditions mirroring diabetes (40 mM glucose) and metabolic syndrome (25 mM glucose with 20 μM linoleic acid and 20 μM oleic acid). Linear wound and Boyden microchemotaxis assays of migration were performed in the presence of S-1-P with and without siRNA against S-1-PR 1 to 5. Assays were performed for activation of ERK1/2, p38(MAPK) and JNK.

RESULTS

Human VSMCs express S-1-PR1, S-1-PR2, and S-1-PR3. There was no significant expression of S-1-PR4 and S-1-PR5. The expression of S-1-PR1 and S-1-PR3 is enhanced under high glucose conditions and metabolic syndrome conditions. Migration of VSMC in response to S-1-P is enhanced 2-fold by diabetes and 4-fold by metabolic syndrome. In diabetes, S-1-PR1 expression is enhanced, while S-1-PR2 and S-1-PR3 expression are both maintained. In metabolic syndrome, S-1-PR1 and 3 expressions are enhanced and that of S-1-PR2 is reduced. siRNA to S-1-PR1 results in a 2-fold reduction in S-1-P-mediated cell migration under all conditions. siRNA to S-1-PR2 enhanced cell migration only under normal conditions, while siRNA S-1-PR3 decreased migration in metabolic syndrome only. Down-regulation of S-1-PR1 reduced ERK1/2 activation in response to S-1-P, while that of S-1-PR2 had no effect under normal conditions. In diabetes, down-regulation of S-1-PR1 reduced activation of all three MAPKs. In metabolic syndrome, down-regulation of S-1-PR1 and S-1-PR3 reduced activation of all three MAPKs.

CONCLUSION

S-1-PR 1, 2, and 3 regulate human VSMC migration and their expression level and function are modulated by conditions simulating diabetes and metabolic syndrome.

Systematic Review of Chinese Herbal Medicines for Preventing in-Stent Coronary Restenosis after Percutaneous Coronary Intervention

Percutaneous coronary intervention (PCI) with stent placement is a standard treatment for coronary artery disease (CAD). In-stent restenosis after PCI remains a challenging clinical problem. In China, Chinese herbal medicines (CHMs) are widely used for preventing restenosis. This paper systematically reviewed the literature on the effectiveness and safety of CHMs in preventing restenosis after PCI in patients with CAD. Electronic databases were searched for randomized controlled trials that compared CHMs plus RWM with the same RWM plus placebo in preventing restenosis after PCI. A total of 52 trials (4905 patients) on 34 CHMs met the inclusion criteria and were analyzed. Ten trials had low risk of bias. Methodological quality of included trials was generally poor. Meta-analysis showed that at the end of at least 3 months' followup, CHMs plus RWM could significantly reduce restenosis rate, cardiac mortality, recurrence rate of angina, acute myocardial infarction, numbers of repeat PCI, and numbers of coronary artery bypass graft. Reported adverse events included gastrointestinal upset, granulocytopenia, and increased alanine transaminase (ALT). CHMs may help prevent restenosis, thus reducing cardiac mortality after PCI. Caution should be exercised in drawing a definitive conclusion due to the poor methodological quality of the trials reviewed.

Restenosis after PCI. Part 1: pathophysiology and risk factors

Restenosis is a complex disease for which the pathophysiological mechanisms have not yet been fully elucidated, but are thought to include inflammation, proliferation, and matrix remodeling. Over the years, many predictive clinical, biological, (epi)genetic, lesion-related, and procedural risk factors for restenosis have been identified. These factors are not only useful in risk stratification of patients, they also contribute to our understanding of this condition. Furthermore, these factors provide evidence on which to base treatment tailored to the individual and aid in the development of novel therapeutic modalities. In this Review, we will evaluate the available evidence on the pathophysiological mechanisms of restenosis and provide an overview of the various risk factors, together with the possible clinical application of this knowledge.

Impact of acute gain on clinical outcomes of patients treated with sirolimus-eluting stent. - A sub-analysis study from the STLLR trial-

BACKGROUND

Geographical miss (GM), representing suboptimal drug-eluting stent deployment, is associated with an increased risk of target lesion revascularization (TLR) and myocardial infarction. The impact of suboptimal stenting techniques on clinical outcomes in diabetics remains unknown.

METHODS AND RESULTS

Stent deployment Techniques on cLinicaL outcomes of patients treated with the cypheR(TM) stent (STLLR) is the first multicenter, large trial to prospectively evaluate outcomes associated with sirolimus-eluting stent (SES) deployment techniques. Axial GM and longitudinal GM (LGM), defined as a balloon injured segment or a diseased segment not covered by a SES, were assessed by an independent core laboratory. One-year outcomes between diabetics and non-diabetics and their relationship with GM were assessed. This substudy included 1,336 patients, 28.8% with diabetes. In non-LGM patients, TLR was similarly low in both diabetics and non-diabetics (2.0% vs. 2.0%, P=NS). However, TLR increased 4.1 times in diabetics (8.0%) and 1.9 times in non-diabetics (3.8%) in the presence of LGM (P=0.03). Axial GM had no impact on outcomes. By univariate analysis, stent length, acute gain, and LGM were the predictors of TLR in the total cohort. However, by multivariate analysis, acute gain was the only predictor of TLR (P=0.03), independently of LGM or diabetes.

CONCLUSIONS

Acute gain is the exclusive predictor of TLR after SES implantation. Particularly in diabetics, the negative impact of LGM on TLR seems to be amplified. Diligent SES deployment for larger acute gain is critical to improve clinical outcomes.

Long-term type 1 diabetes enhances in-stent restenosis after aortic stenting in diabetes-prone BB rats

Type 1 diabetic patients have increased risk of developing in-stent restenosis following endovascular stenting. Underlying pathogenetic mechanisms are not fully understood partly due to the lack of a relevant animal model to study the effect(s) of long-term autoimmune diabetes on development of in-stent restenosis. We here describe the development of in-stent restenosis in long-term (~7 months) spontaneously diabetic and age-matched, thymectomized, nondiabetic Diabetes Prone BioBreeding (BBDP) rats (n = 6-7 in each group). Diabetes was suboptimally treated with insulin and was characterized by significant hyperglycaemia, polyuria, proteinuria, and increased HbA_1c levels. Stented abdominal aortas were harvested 28 days after stenting. Computerized morphometric analysis revealed significantly increased neointima formation in long-term diabetic rats compared with nondiabetic controls. In conclusion, long-term autoimmune diabetes in BBDP rats enhances in-stent restenosis. This model can be used to study the underlying pathogenetic mechanisms of diabetes-enhanced in-stent restenosis as well as to test new therapeutic modalities.

Cryoplasty versus conventional balloon angioplasty of the femoropopliteal artery in diabetic patients: long-term results from a prospective randomized single-center controlled trial

The purpose of this study was to investigate the immediate and long-term results of cryoplasty versus conventional balloon angioplasty in the femoropopliteal artery of diabetic patients. Fifty diabetic patients (41 men, mean age 68 years) were randomized to cryoplasty (group CRYO; 24 patients with 31 lesions) or conventional balloon angioplasty (group COBA; 26 patients with 34 lesions) of the femoropopliteal artery. Technical success was defined as <30% residual stenosis without any adjunctive stenting. Primary end points included technical success, primary patency, binary in-lesion restenosis (>50%), and freedom from target lesion recanalization. Cox proportional hazards regression analysis was performed to adjust for confounding factors of heterogeneity. In total, 61.3% (19 of 31) in group CRYO and 52.9% (18 of 34) in group COBA were de novo lesions. More than 70% of the lesions were Transatlantic Inter-Society Consensus (TASC) B and C in both groups, and 41.4% of the patients in group CRYO and 38.7% in group COBA suffered from critical limb ischemia. Immediate technical success rate was 58.0% in group CRYO versus 64.0% in group COBA (p = 0.29). According to 3-year Kaplan-Meier estimates, there were no significant differences with regard to patient survival (86.8% in group CRYO vs. 87.0% in group COBA, p = 0.54) and limb salvage (95.8 vs. 92.1% in groups CRYO and COBA, respectively, p = 0.60). There was a nonsignificant trend of increased binary restenosis in group CRYO (hazard ratio [HR] 1.3; 95% CI 0.6-2.6, p = 0.45). Primary patency was significantly lower in group CRYO compared with group COBA (HR 2.2; 95% CI 1.1-4.3, p = 0.02). Significantly more repeat intervention events because of recurrent symptoms were required in group CRYO (HR 2.5; 95% CI 1.2-5.3, p = 0.01). Cryoplasty was associated with lower primary patency and more clinically driven repeat procedures after long-term follow-up compared with conventional balloon angioplasty.

Sex-dependent differences in cytochrome P450 3A activity as assessed by midazolam disposition in humans: a meta-analysis

Controversy exists concerning the sex-dependent differences in cytochrome P450 3A activity in humans. Meta-analysis of selected studies may address this question. Meta-analysis was performed on published or unpublished data in terms of sex-dependent differences in midazolam (MDZ) disposition in humans. The following pharmacokinetic parameters were included for the analysis: MDZ oral and systemic clearance, area under the concentration-time curve (AUC) of oral and intravenous MDZ, MDZ oral bioavailability (F), and MDZ gastrointestinal extraction (E(G)). Ten studies including 409 healthy volunteers were identified. Women exhibited 16% higher weight-corrected MDZ oral clearance (P < 0.001) and 20% higher systemic clearance (P = 0.002) than men. No significant difference in the AUC after oral dosing of MDZ was noted between sexes. Women showed lower AUC of intravenous MDZ than men (P = 0.02). No sex-dependent differences were observed in F and E(G). In conclusion, women showed significantly greater hepatic CYP3A activity than men, whereas no sex-dependent difference in intestinal CYP3A activity was observed.

Is the evidence from clinical trials for cardiovascular risk or harm for glitazones convincing?

Thiazolidinediones (TZDs), agonists of the nuclear receptor peroxisome proliferator-activated receptor-gamma, induce the expression of many genes, including several enzymes and transporters involved in glucose and lipid metabolism. Although the efficacy of TZDs on blood glucose control in type 2 diabetes is not questionable, their cardiovascular effects have been debated, with beneficial or harmful actions suggested by different authors. This article reviews the available clinical evidence on the cardiovascular effects of TZDs, discussing possible mechanisms underlying the observed effects and suggesting some directions for future research.

Effect of thiazolidinediones on in-stent restenosis in patients after coronary stenting: a meta-analysis of randomized controlled trials

BACKGROUND

Recent experimental studies have demonstrated that thiazolidinediones (TZDs) therapy inhibits proliferation and migration of vascular smooth muscle cells, accelerates endothelium reparation and attenuates neointimal hyperplasia. It implies that TZDs therapy may have beneficial effects on in-stent restenosis (ISR). Several small-sample clinical trials have evaluated the effect of TZDs therapy on ISR, however, the results were inconsistent across trials.

METHODS AND RESULTS

We performed a meta-analysis of all relevant randomized controlled trials to evaluate the effect of TZDs therapy on in-stent restenosis in patients undergoing coronary stenting. Eight trials involving 366 patients were included in this study. TZDs therapy was associated with a significant reduction in the risk of ISR in both diabetic (RR 0.37, 95% CI 0.23-0.59; P<0.0001) and non-diabetic patients (RR 0.16, 95% CI 0.05-0.45; P=0.0006). TZDs therapy was associated with a significant reduction in late lumen loss (WMD -0.54 mm, 95% CI -0.87 mm, -0.22 mm; P=0.001), percent diameter stenosis (WMD -15.7%, 95% CI -19.4%, -12.0%; P<0.00001), neointimal area/volume (SMD -0.76, 95% CI -1.13, -0.39; P<0.0001) and target lesion revascularization (RR 0.32, 95% CI 0.18-0.57; P=0.0001).

CONCLUSIONS

Our study suggests that TZDs therapy is an effective strategy in preventing ISR in both diabetic and non-diabetic patients undergoing coronary stenting. More studies, especially large multi-centre RCTs, are still warranted to further clarify the anti-restenotic effect of TZDs therapy.

Impact of the metabolic syndrome on angiographic and clinical events after coronary intervention using bare-metal or sirolimus-eluting stents

Patients with metabolic syndrome (MS) are at increased risk for cardiovascular events. Although the number of patients with MS requiring coronary revascularization is increasing rapidly, the impact of MS on clinical events and restenosis in patients who undergo stent placement is not well defined. Seven hundred thirty-four consecutive patients with 734 de novo coronary lesions (<50 mm lesion length, reference vessel diameter <3.5 mm) were enrolled in this study. Four hundred thirty-seven patients were treated with bare-metal stents, and 297 patients were treated with sirolimus-eluting stents. Patients with bifurcation lesions, left main lesions, and ST-segment-elevation myocardial infarctions were excluded from the study. Patients were categorized into 3 groups: those with (1) diabetes mellitus (DM), (2) MS without DM, and (3) no MS and no DM. MS was defined according to American Heart Association and National Heart, Lung, and Blood Institute criteria (the presence of > or =3 of the following criteria: obesity, hypertension, hypertriglyceridemia, low high-density lipoprotein cholesterol, and increased fasting glucose). Clinical follow-up was performed for > or =1 year (mean 27.5 +/- 18.1 months). One hundred sixty-four patients (22%) had DM, 180 patients (25%) had MS without DM, and 390 patients (53%) had no MS and no DM. Baseline clinical and angiographic parameters were comparable among the 3 groups, including lesion length and reference vessel diameter. In patients treated with bare-metal stents, the rates of major adverse cardiac events (MACEs) at 12 months were 14% in patients without DM or MS, 18% in those with MS but no DM, and 33% in those with DM (p = 0.046). In patients treated with sirolimus-eluting stents, the MACE rates were 3% in patients without DM or MS, 4% in those with MS, and 13% in those with DM (p = 0.034). DM (odds ratio 2.14, 95% confidence interval 1.48 to 3.07, p <0.001) and bare-metal stent (odds ratio 2.51, 95% confidence interval 1.49 to 4.22, p <0.001) implantation were independent predictors of MACEs during follow-up, whereas MS was not predictive. Similarly, MS was not a predictor of target lesion revascularization. In conclusion, patients with MS did not have an increased risk for target lesion revascularization or a greater MACE rate compared with control patients during a 12 month follow-up period after bare-metal or drug-eluting stent placement. In contrast, DM is associated with significantly increased event rates.