Long-term care after percutaneous coronary intervention: focus on the role of antiplatelet therapy

Single versus dual antiplatelet therapy impact on coagulation/thrombosis post PAD revascularization

OBJECTIVE

To evaluate and compare the impact of single- versus dual-antiplatelet (SAPT vs DAPT) therapy on coagulation profiles and postoperative outcomes in patients with peripheral arterial disease (PAD).

METHODS

Patients with PAD undergoing lower extremity revascularization from December 2020 to August 2023 were prospectively enrolled in this cohort study and followed for one year to record the incidence of thrombotic events (TEs). These events include arterial graft/stent occlusion or stenosis, as identified through Doppler ultrasonography or angiography. Patients were categorized by type of intervention (open vs. endovascular) and further stratified by thromboprophylaxis regimen (SAPT vs DAPT). Descriptive statistics were conducted to characterize each group. Differences in continuous variables were analyzed using Student's t-test, while categorical variables were evaluated using Fisher's exact test. Kaplan-Meier survival curves and cox proportional hazard assessed the thrombosis probability between groups.

RESULTS

A total of 157 patients were analyzed, of which 56 were open and 101 were endovascular. In the endovascular group, the majority of patients were on DAPT (61.4%), whereas in the open procedure, most individuals were on SAPT (78.6%). DAPT recipients exhibited a lower prothrombotic profile than SAPT recipients in either operative cohort (p < .05). However, the incidence of index TEs was similar between medication groups within each cohort over the one-year follow-up period. DAPT was associated with a decreased incidence of recurrent TEs in the open intervention group (p < .001), indicating its potential for reducing subsequent thrombotic complications following an index TE. Additionally, there was no significant difference in thrombosis probability between endovascular and open procedures (p = .73), nor between DAPT and SAPT groups across both procedure modalities (p = .98).

CONCLUSION

While DAPT demonstrated lower prothrombotic thromboelastography with platelet mapping profiles compared to SAPT, this did not translate into differences in index TEs across surgical modalities.

A novel noble metal stent coating reduces in vitro platelet activation and acute in vivo thrombosis formation: a blinded study

Inherent to any stenting procedure is the prescription of dual antiplatelet therapy (DAPT) to reduce the platelet response. Clinical guidelines recommend 6-12 months of DAPT, depending on stent type, clinical picture and patient factors. Our hypothesis is that a nanostructured noble metal coating has the potential to reduce protein deposition and platelet activation. These effects would reduce subsequent thrombo-inflammatory reactions, potentially mitigating the need for an extensive DAPT in the acute phase. Here, a noble metal nanostructure coating on stents is investigated. Twelve pigs underwent endovascular implantation of coated and non-coated stents for paired comparisons in a blinded study design. The non-coated control stent was placed at the contralateral corresponding artery. Volumetric analysis of angiographic data, performed by a treatment blinded assessor, demonstrated a significant thrombus reduction for one of the coatings compared to control. This effect was already seen one hour after implantation. This finding was supported by in vitro data showing a significant reduction of coagulation activation in the coated group. This novel coating shows promise as an implant material addition and could potentially decrease the need for DAPT in the early phases of stent implementation.

Clinical non-effectiveness of clopidogrel use for peripheral artery disease in patients with CYP2C19 polymorphisms: a systematic review

PURPOSE

To conduct a systematic review to identify studies that assessed the association between CYP2C19 polymorphisms and clinical outcomes in peripheral artery disease (PAD) patients who took clopidogrel.

METHODS

We systematically searched Ovid EMBASE, PubMed, and Web of Science from November 1997 (inception) to September 2020. We included observational studies evaluating how CYP2C19 polymorphism is associated with clopidogrel's effectiveness and safety among patients with PAD. We extracted relevant information details from eligible studies (e.g., study type, patient population, study outcomes). We used the Risk of Bias in Non-randomized Studies-of Interventions (ROBINS-I) Tool to assess the risk of bias for included observational studies.

RESULTS

The outcomes of interest were the effectiveness and safety of clopidogrel. The effectiveness outcomes included clinical ineffectiveness (e.g., restenosis). The safety outcomes included bleeding and death related to the use of clopidogrel. We identified four observational studies with a sample size ranging from 50 to 278. Outcomes and comparison groups of the studies varied. Three studies (75%) had an overall low risk of bias. All included studies demonstrated that carrying CYP2C19 loss of function (LOF) alleles was significantly associated with reduced clinical effectiveness and safety of clopidogrel.

CONCLUSIONS

Our systematic review showed an association between CYP2C19 LOF alleles and reduced functions of clopidogrel. The use of CYP2C19 testing in PAD patients prescribed clopidogrel may help improve the clinical outcomes. However, based on the limited evidence, there is a need for randomized clinical trials in PAD patients to test both the effectiveness and safety outcomes of clopidogrel.

Reduced-Dose Prasugrel versus Clopidogrel for Patients Undergoing Percutaneous Coronary Intervention

Whether reduced-dose prasugrel has a better efficacy or safety than standard-dose clopidogrel remains unknown in patients undergoing percutaneous coronary intervention (PCI).A systematic search of PubMed, EMBASE, Google Scholar, and Cochrane Library from database inception to May 1, 2020 was performed to compare the clinical outcomes in patients with acute coronary syndrome or stable coronary artery disease undergoing PCI between those treated with reduced-dose prasugrel and clopidogrel. The pooled odds ratio (OR) and 95% confidence interval (CI) were calculated using the fixed-effect or random-effect model if significant heterogeneity was observed. The primary efficacy endpoint was major adverse cardiovascular events (MACE), including cardiovascular (CV) death, myocardial infarction (MI), or ischemic stroke. The primary safety endpoint was all bleeding events.Overall, seven studies with 32,951 patients with PCI were included in the analysis. Reduced-dose prasugrel was associated with a lower risk of MACE than clopidogrel (OR 0.80, 95% CI 0.67-0.97). Except for MI (OR 0.74, 95% CI 0.56-0.98), the secondary efficacy endpoints of CV death, ischemic stroke, all-cause death, and stent thrombosis were similar. For the primary safety endpoint of all bleeding events, there was no significant difference between reduced-dose prasugrel and clopidogrel (OR 1.31, 95% CI 0.87-1.98), but the risk of minor bleeding was significantly higher in reduced-dose prasugrel (OR 1.73, 95% CI 1.25-2.41).In patients undergoing PCI, a lower risk of MACE was found in patients receiving reduced-dose prasugrel than in those with clopidogrel, but a higher risk of minor bleeding events was noted.

Characterization of a Sandwich PLGA-Gallic Acid-PLGA Coating on Mg Alloy ZK60 for Bioresorbable Coronary Artery Stents

Absorbable magnesium stents have become alternatives for treating restenosis owing to their better mechanical properties than those of bioabsorbable polymer stents. However, without modification, magnesium alloys cannot provide the proper degradation rate required to match the vascular reform speed. Gallic acid is a phenolic acid with attractive biological functions, including anti-inflammation, promotion of endothelial cell proliferation, and inhibition of smooth muscle cell growth. Thus, in the present work, a small-molecule eluting coating is designed using a sandwich-like configuration with a gallic acid layer enclosed between poly (d,l-lactide-co-glycolide) layers. This coating was deposited on ZK60 substrate, a magnesium alloy that is used to fabricate bioresorbable coronary artery stents. Electrochemical analysis showed that the corrosion rate of the specimen was ~2000 times lower than that of the bare counterpart. The released gallic acid molecules from sandwich coating inhibit oxidation by capturing free radicals, selectively promote the proliferation of endothelial cells, and inhibit smooth muscle cell growth. In a cell migration assay, sandwich coating delayed wound closure in smooth muscle cells. The sandwich coating not only improved the corrosion resistance but also promoted endothelialization, and it thus has great potential for the development of functional vascular stents that prevent late-stent restenosis.

Risk factors associated with bleeding after multi antithrombotic therapy during implantation of cardiac implantable electronic devices

Previous studies showed that continuous anticoagulation or single antiplatelet therapy during implantations of cardiac implantable electronic devices (CIED) was relatively safe. However, the safety of continuous multi antithrombotic therapy (AT) in patients undergoing CIED interventions has not been clearly defined. We sought to evaluate the safety of this therapy during CIED implantations. A total of 300 consecutive patients (mean 69 years old, 171 males) with CIED implantations were enrolled in this study. The patients were divided into 6 groups [No-AT, oral anticoagulant therapy (OAT), single antiplatelet therapy (SAPT), OAT and SAPT, dual antiplatelet therapy (DAPT), triple AT (TAT)], and the perioperative complications were evaluated. Clinically significant pocket hematomas (PH) were defined as PH needing surgical intervention, prolonged hospitalizations, interruption of AT, or blood product transfusions. There were 129, 89, 49, 20, 10, and 3 patients in No-AT, OAT, SAPT, OAT + SAPT, DAPT, and TAT groups, respectively. The occurrence of clinically significant PH and thromboembolism did not differ among 6 groups (p = 0.145 and p = 0.795, respectively). However, high HAS-BLED score and valvular heart disease (VHD) were associated with clinically significant PH (p = 0.014 and p = 0.015, respectively). Continuous multi AT may be tolerated, but patients with high HAS-BLED score or VHD would require a careful attention during CIED implantations.

Prasugrel Hydrochloride

A comprehensive profile of prasugrel HCl is reported herein with 158 references. A full description including nomenclature, formulae, elemental analysis, and appearance is included. Methods of preparation for prasugrel HCl, its intermediates, and derivatives are fully discussed. In addition, the physical properties, analytical methods, stability, uses and applications, and pharmacology of prasugrel HCl are also discussed.

P2Y12 Receptor Inhibitors in Acute Coronary Syndromes: What Is New on the Horizon?

Dual antiplatelet therapy with aspirin and a P2Y₁₂ receptor inhibitor represents the cornerstone therapy for patients with acute coronary syndromes or undergoing percutaneous interventions, leading to a reduction of subsequent ischemic events. Variable response to clopidogrel has received close attention, and pharmacokinetic, pharmacodynamic, and pharmacogenomic factors have been identified as culprits. This led to the introduction of newer, potentially safer, and more effective antiplatelet agents (prasugrel and ticagrelor). Additionally, several point-of-care assays of platelet function have been developed in recent years to rapidly screen individuals on antiplatelet therapy. While the routine use of platelet function testing is uncertain and not currently recommended, it may be useful in instances when the degree of platelet inhibition may be uncertain such as high-risk patients undergoing percutaneous coronary intervention or when there may be a suspected pharmacodynamic interaction with other drugs. The current paper focuses on the P2Y₁₂ receptor inhibitors and their pharmacogenetics and indications in patients with acute coronary syndromes or receiving percutaneous coronary interventions as well as the applicability of platelet function testing in this clinical context.

Out-of-hospital deaths within 30 days following hospitalization where percutaneous coronary intervention was performed

Much has been learned about predictors of in-hospital death after percutaneous coronary intervention (PCI), but little is known about the predictors of short-term death after discharge. This is particularly important for PCI, with its short postprocedural hospitalization and concern about postprocedural events such as stent thrombosis and need for emergency cardiac surgery. The focus of this study was all 51,695 patients who underwent PCI in New York State from January 1, 2007, and December 31, 2007, who were discharged alive by December 31, 2007. All patients were followed for 30 days after discharge to determine if they died after discharge within 30 days. The in-hospital and 30-day mortality rate for PCI patients was 0.94%, the in-hospital mortality rate was 0.56%, and the mortality rate for deaths that occurred after discharge within 30 days of the procedure was 0.38%. Of the PCI deaths that occurred either in the index admission or after discharge within 30 days, 40.5% occurred after discharge. The percentage of short-term (in-hospital or within 30 days) deaths in hospitals with ≥10 short-term deaths ranged from 15% to 71%. In conclusion, compared to PCI patients dying in the index admission, patients who died <30 days after discharge were younger, had better ventricular function, were less likely to have had recent myocardial infarctions, and were less likely to have had postprocedural complications. Most deaths in the 30-day group were cardiovascular, and most were cardiac and acute. A small percentage were related to chronic cardiac disease or to vascular disease.

A case of stent thrombosis occurred at 5 years after sirolimus-eluting stent implantation

Drug-eluting stents (DES) have reduced the rate of repeated revascularization of target lesions. For this reason, DES are considered to be superior to bare-metal stents in reducing the restenosis rate. However, some problems have been reported after implantation of DES. One of them, stent thrombosis, has arisen as a fatal complication. Dual antiplatelet therapy is recommended for at least 12 months after implantation of DES to prevent stent thrombosis. Here, we report a case of very late stent thrombosis that occurred 1 week after discontinuation of clopidogrel at 5 years (1832 days) after implantation of a sirolimus-eluting stent.

Etiology, prevention, and treatment of dermal filler complications

The availability of dermal fillers for multiple cosmetic indications has led to a dramatic increase in their application. Although fillers are generally regarded as safe tools for soft tissue augmentation, complications can occur. Therefore, to describe and review the complications associated with the currently-available dermal filling agents, the authors conducted a literature review in peer-reviewed journals and present the reported complication rates. They also describe current strategies to avoid, diagnose, and manage complications if they do occur.

Temporal changes in circulating P-selectin, plasminogen activator inhibitor-1, magnesium, and creatine kinase after percutaneous coronary intervention

OBJECTIVE

This study aims to determine the mechanisms underlying restenosis and ischemia-reperfusion injury of the myocardium after percutaneous coronary intervention (PCI).

METHODS

The present study examined serial changes (5 min, 30 min, 2 h, 6 h, and 24 h after PCI) in circulating P-selectin, plasminogen activator inhibitor-1 (PAI-1), magnesium (Mg), and creatine kinase-myocardial band fraction (CK-MB) levels, which may be associated with restenosis and myocardial injury in patients undergoing PCI. The occurrence rates of major adverse cardiovascular events were collected over a six-month follow-up.

RESULTS

PCI induced an early elevation of P-selectin, which correlated positively with the inflation pressure used in the PCI procedure. PCI also caused a significant and sustained decrease in serum Mg in PCI patients, without an effect on PAI-1. An increase in CK-MB was observed in PCI patients, although values were within normal reference range. In addition, elevated P-selectin and decreased Mg measured shortly after the coronary angioplasty procedure were associated with recurrent treatment and heart failure, respectively.

CONCLUSIONS

Our study demonstrates that PCI induces temporal changes of P-selectin, Mg, and CK-MB, which may be involved in restenosis and ischemia-reperfusion injury. These findings highlight the need for using antiplatelet therapy and Mg to reduce the risks associated with PCI.

Prasugrel as antiplatelet therapy in patients with acute coronary syndromes or undergoing percutaneous coronary intervention

The authors provide information on prasugrel, compare and contrast it with clopidogrel, and review the use of prasugrel in patients who require an antiplatelet agent.

Very late stent thrombosis of DES implanted patient during noncardiac surgery: A case report

Very late stent thrombosis after implantation of drug eluting stent is rare, but its consequences are potentially fatal. Stent thrombosis may be occurred in perioperative period because of interruption of anticoagulation therapy and intraoperative hypercoagulability. We report a case of very late stent thrombosis in a 49-year-old male patient during total gastrectomy. ST-segment elevation in lead II occurred during the surgery and followed by cardiac arrest. After external cardiac massage and electrocardioversion, normal sinus rhythm was restored. Postoperative 12 lead ECG showed ST-segment elevation in leads II, III, aVF and serum cardiac enzymes such as CPK, CK-MB, and Troponin T were markedly elevated. Postoperative coronary angiography showed complete occlusion of the right coronary artery stent. Emergency percutaneous transluminal coronary angioplasty was performed and the patient recovered uneventfully.

[Drug-eluting stents: implications for surgery patients]

Percutaneous coronary intervention (PCI) has a special role in the treatment of coronary heart disease. The insertion of drug-eluting stents (DES) requires dual anti-platelet therapy for at least 1 year which makes planned and emergency surgery difficult. There is a dilemma between high risk of stent thrombosis and perioperative bleeding. There is no evidence-based, bridging therapy option available perioperatively. This complex of problems should be considered whenever PCI is performed. An interdisciplinary approach is obligatory in these imminent conditions to proceed with either interventional or surgical revascularization. Co-existing malignancies and disorders which must be treated surgically should be excluded before PCI. Furthermore, DES and dual anti-platelet therapy produce unanswered forensic questions. On legal grounds it is not possible to proceed with surgery in cases of medication with anti-platelet therapy. Therefore, it is mandatory to discuss the possible answers to this problem with health care lawyers. The patient must be informed about this complex of problems.

Higher platelet activity is present in patients with restenosis after percutaneous coronary intervention compared with patients with an occlusion of coronary artery bypass graft

The aim of the study was to compare platelet activity between patients with an occlusion of bypass graft after coronary artery bypass graft surgery and restenosis after percutaneous coronary intervention (PCI); that is, between patients with reappearance of ischemia after two different kinds of coronary revascularization. Thirty patients were studied in a cross-sectional designed study. Fifteen of them were patients with the worst bypass graft patency from Prague-4 study (control protocol-driven coronary angiography performed at 1 year after surgery; originally 47 bypass grafts implanted, 94% of venous grafts occluded). The remaining 15 were patients with restenosis 3-12 months after PCI. Blood samples were drawn at least 12 weeks after coronary angiography. Platelet activity was determined by membrane expression of P-selectin (CD62P, % of positive cells) by flow cytometry, aggregability by ADP aggregometry. Data are expressed as mean +/- SEM. Both groups were similar with respect to age, BMI and presence of diabetes mellitus. No patient suffered from acute coronary syndrome. P-selectin expression was significantly higher in the patients with restenosis compared with patients with bypass graft occlusion (1.96 +/- 0.07 vs. 0.77 +/- 0.03, P < 0.001, Wilcoxon test). ADP aggregometry was not different between groups (55.5 +/- 1.1 vs. 56.1 +/- 0.8, P = NS). Higher platelet activity is present in the patients with restenosis after PCI compared with the patients with the occlusion of bypass graft. Platelet activity play more important role in the development of restenosis after PCI compared with the occlusion of bypass graft after coronary artery bypass graft surgery, at least in the period up to 1 year after revascularization.

Coronary artery stents: Part I. Evolution of percutaneous coronary intervention

The subspecialty of interventional cardiology has made significant progress in the management of coronary artery disease over the past three decades with the development of percutaneous coronary transluminal angioplasty, atherectomy, and bare-metal and drug-eluting stents (DES). Bare-metal stents (BMS) maintain vessel lumen diameter by acting as a scaffold and prevent collapse incurred by angioplasty. However, these devices cause neointimal hyperplasia leading to in-stent restenosis and requiring reintervention in more than 20% of patients by 6 mo. DES (sirolimus and paclitaxel) prevent restenosis by inhibiting neointimal hyperplasia. However, DESs also delay endothelialization, causing the stents to remain thrombogenic for an extended, yet unknown, period of time. Late stent thrombosis is associated with a 45% mortality rate. Premature discontinuation of antiplatelet therapy, particularly clopidogrel, is the strongest predictor of stent thrombosis. Sixty percent of patients receive stents for off-label (unapproved) indications, which also increases the frequency of stent thrombosis. Clopidogrel and aspirin are the cornerstone of therapy in the prevention of stent thrombosis in both BMS and DES. Recommendations pertaining to the optimal duration of dual-antiplatelet therapy have been debated. Both the Food and Drug Administration and the American Heart Association/American College of Cardiologists, in association with other major societies, have made recommendations to extend the duration of dual-antiplatelet therapy in patients with DES to 1 yr. The 6-wk duration of dual-antiplatelet therapy in patients with BMS remains unchanged. All patients with coronary stents must remain on life-long aspirin monotherapy. Since the introduction of percutaneous transluminal coronary angioplasty for the treatment of coronary atherosclerosis, the practice of percutaneous coronary intervention has undergone a dramatic transformation from simple balloon dilation catheters to sophisticated mechanical endoprostheses. These advancements have impacted the practice of perioperative medicine. In this series of two articles, in Part I we will review the evolution of percutaneous coronary intervention and discuss the issues associated with percutaneous transluminal coronary angioplasty and coronary stenting; in Part II we will discuss perioperative issues and management strategies of coronary stents during noncardiac surgery.

A tale of two stents: perioperative management of patients with drug-eluting coronary stents

Drug-eluting stents were introduced into clinical practice to decrease coronary stent restenosis rates. Though remarkably effective in reducing this complication, recent data reveal that drug-eluting stents pose a significant risk for late stent thrombosis, an event strongly correlated with discontinuation of anti-platelet therapy. Because anti-platelet agents are often discontinued perioperatively, patients with DES are at risk for perioperative stent thrombosis and myocardial infarction. Along with a review of the recent literature, we present two cases of patients with drug-eluting stents scheduled for renal transplantation. Two distinct antithrombotic management strategies illustrate the risk of either approach-bleeding and transfusion versus stent thrombosis and myocardial infarction.

Association of Circulating Transforming Growth Factor beta, Tumor Necrosis Factor alpha and Basic Fibroblast Growth Factor with Restenosis after Transluminal Angioplasty

OBJECTIVES

To assess prospectively the early time course of Transforming Growth Factor beta-1 (TGFbeta-1), basic Fibroblast Growth Factor (bFGF) and Tumor Necrosis Factor alpha (TNFalpha) as possible contributors to restenosis development after angioplasty.

DESIGN

Prospective Study.

METHODS

The levels of the soluble forms of these factors in the early response to Percutaneous Transluminal Angioplasty (PTA) in the arteries of the lower limb were prospectively assessed. 32 patients with peripheral arterial occlusive disease (PAOD), presenting with intermittent claudication (Fontaine stage IIb) were scheduled for angioplasty treatment. Serum levels of TGFbeta-1, TNFalpha and bFGF were assessed before intervention, 15 and 60 minutes after, 24 hours after as well as 2 and 4 weeks after intervention. We compared the distribution patterns between patients treated with balloon angioplasty and patients who required secondary stent implantation. Endpoint was the development of restenosis within 6 months after interventional treatment, defined as a lumen diameter reduction of more than 50% by ultrasound measurement compared to the result after PTA.

RESULTS

The patients who later developed restenosis had significantly higher levels of TGFbeta-1 at 15 minutes, 24 hours and 2 weeks after PTA (p<0.05). TNFalpha and bFGF were only detected in a few patients and no significant change of serum levels was observed.

CONCLUSION

The results demonstrate a possible role of TGFbeta-1 in the formation of restenosis after PTA.

Coronary artery stents and non-cardiac surgery

The utility of interventional cardiology has developed significantly over the last two decades with the introduction of coronary angioplasty and stenting, with the associated antiplatelet medications. Acute coronary stent occlusion carries a high morbidity and mortality, and the adoption of therapeutic strategies for prophylaxis against stent thrombosis has major implications for surgeons and anaesthetists involved in the management of these patients in the perioperative period. Currently, there is limited published information to guide the clinician in the optimal care of patients who have had coronary stents inserted when they present for non-cardiac surgery. This review examines the available literature on the perioperative management of these patients. A number of key issues are identified: the role of surgery vs percutaneous coronary intervention for coronary revascularization in the preoperative period; the different types of coronary stents currently available; the emerging issues related to drug-eluting stents; the pathophysiology of coronary stent occlusion; and the recommended antiplatelet regimes that the patient with a coronary stent will be receiving. The role of preoperative platelet function testing is also discussed, and the various available tests are listed. Appropriate management by all the clinicians involved with patients with coronary stents undergoing a variety of non-cardiac surgical procedures is essential to avoid a high incidence of postoperative cardiac mortality and morbidity. The review examines the evidence available for the perioperative strategies aimed at reducing adverse outcomes in a number of different clinical scenarios.

Use of antiplatelet drugs in secondary prevention in older persons with atherothrombotic disease

Unless there are contraindications to the use of aspirin, aspirin should be used in treating patients with acute myocardial infarction (MI) and continued indefinitely to reduce vascular death, nonfatal MI, and nonfatal stroke. Clopidogrel added to aspirin has been shown to be beneficial in the treatment of patients with acute ST-elevation MI. Patients with unstable angina or non-ST-elevation MI should be treated with aspirin plus clopidogrel for at least 9 months to reduce vascular death, nonfatal MI, and nonfatal stroke. Patients with prior MI should be treated indefinitely with aspirin and with clopidogrel if aspirin is contraindicated. Patients with ischemic stroke should be treated with either aspirin or clopidogrel indefinitely. Extended release dipyridamole plus low dose aspirin has been shown to be more efficacious than low dose aspirin in only one large study, and is associated with an insignificant increase in nonfatal MI and vascular death over low dose aspirin alone. Clopidogrel is significantly more effective than aspirin in reducing vascular death, nonfatal MI, and nonfatal stroke in patients with peripheral arterial disease.

Drug eluting stents

Dual antiplatelet therapy should not be discontinued without referral to a cardiologist

Endovaskuläre Behandlung intrakranieller Stenosen

Intracranial stenoses cause 5-10% of all strokes and are increasingly detected by means of modern imaging methods. The stroke danger of high-grade symptomatic stenoses is relatively high, with an annual risk of approximately 10% under medical treatment. Coumadin increases the risk of hemorrhage, and after risk/benefit considerations, antiplatelets should be preferred for antithrombotic therapy. Despite optimized medical treatment, a small group of patients with recurrent symptoms or symptomatic stenoses without adequate collateral supply probably carry higher spontaneous stroke risk and may be considered for intracranial stenting, which itself is associated with procedural risks of up to 10%. Currently published case series show relatively high complication rates as a major drawback of endovascular treatment, mainly strokes after occlusion of perforating branches extending from the stenotic vessel segment or hemorrhagic complications. According to data from smaller feasibility studies, stroke rates in follow-up after successful stenting seem to be low. The average rate of high-grade restenosis with possible indication for reintervention is 10%. Improvements in endovascular treatment aim at reducing vessel wall trauma during balloon angioplasty by underdilatation or the use of self-expanding stents. Until complication rates are dependably reduced to values of 5-6%, indication for endovascular treatment should be restricted to patients without therapeutic alternatives. According to limited data with large variation between different studies, a prospective multicentric registry is proposed for systematic evaluation and further development of the method.

The safety and efficacy of aspirin and clopidogrel as a combination treatment in patients with coronary heart disease

The use of aspirin and clopidogrel in combination has become part of the standard clinical care of patients with coronary artery disease. The use of this combination provides significant benefits compared with the use of aspirin alone in patients with acute coronary syndromes, and in patients treated with percutaneous coronary intervention with stent placement (both bare metal and drug-eluting stents). Clinical trials have demonstrated significant efficacy of this dual therapy; however, there is the potential for significant bleeding complications from the synergistic antiplatelet effects. In total, it appears that when there is vessel injury (mechanical from perctutaneous coronary intervention or a ruptured plaque), dual antiplatelet therapy with aspirin and clopidogrel results in improved outcomes, albeit with a small but significant inherent risk of increased bleeding.

The 5-Year Projection on the Future of Interventional Cardiology

Interventional cardiology has revolutionized modern cardiovascular care not only with the introduction of new approaches to the treatment of coronary artery disease, but also with the development of new invasive approaches to electrophysiologic procedures and the treatment of noncoronary vascular beds. This revolution continues to gather speed. Creative solutions continue to be proposed, evaluated, and then brought to the patient care arena. Issues remain, but these identify opportunities for continuing improvement.

Use of antiplatelet drugs in secondary prevention in patients with atherothrombotic disease

Unless there are contraindications to the use of aspirin, aspirin should be used to treat patients with acute myocardial infarction (MI) and continued indefinitely to decrease vascular death, nonfatal MI, and nonfatal stroke. Clopidogrel added to aspirin is beneficial in the treatment of patients with acute ST-elevation MI. Patients with unstable angina pectoris or non-ST-elevation MI should be treated with aspirin plus clopidogrel for at least 9 mo to decrease vascular death, nonfatal MI, and nonfatal stroke. Patients with prior MI should be treated indefinitely with aspirin and with clopidogrel if aspirin is contraindicated. Patients with ischemic stroke should be treated with either aspirin or clopidogrel indefinitely. Clopidogrel is significantly more effective than aspirin in reducing vascular death, nonfatal MI, and nonfatal stroke in patients with peripheral arterial disease.