Management of Patients with Carotid Artery Stenosis

Abstract : A stenosis of the internal carotid artery may cause 10-20% of all ischemic strokes. Duplex ultrasound is the diagnostic cornerstone, and CT angiography or MR angiography may be used to confirm the severity of the stenosis or prior to revascularization. Catheter-based digital subtraction angiography is rarely needed for diagnostic purposes. In symptomatic patients, carotid revascularization is indicated in the presence of a stenosis ≥ 50%. In asymptomatic patients, the indication for revascularization based on randomized trials is given at ≥ 60% stenosis, as long as the estimated perioperative death or stroke risk is < 3%. In clinical practice, however, asymptomatic stenoses are usually treated only if luminal narrowing exceeds 70-80% and the patient has a life expectancy of at least 5 years. The choice of the revascularization strategy (endarterectomy vs. stenting) should be based on the patient's surgical risk profile and on the locally available expertise. Independently of the revascularization option, carotid artery stenosis patients remain at risk of cardiovascular events because of the high prevalence of associated coronary artery disease. A broad disease management focusing on risk factor and lifestyle modification may impact quality and duration of life of these patients to a greater extent than the revascularization procedure itsel

Platelet Inhibition in Percutaneous Coronary Interventions

Abstract : Mechanical disruption of atherosclerotic plaques at the time of percutaneous coronary intervention (PCI) is a potent stimulus for arterial thrombosis. Since platelets play a crucial role in the cascade of clot formation, platelet inhibition is an essential step for successful PCI. Aspirin remains the cornerstone of any antithrombotic regimen in the interventional setting. The addition of a thienopyridine is mandatory following stenting to prevent thrombosis of the device. Whenever possible, patients undergoing PCI should be pretreated with clopidogrel and the drug should be continued for up to 1 year. Glycoprotein IIb/IIIa antagonists should be administered in high-risk patients, such as those with acute coronary syndromes, diabetes, or complex coronary anatom

Nachbehandlung nach medikamentös beschichteten Stents

Zusammenfassung: Die medikamentös beschichteten Stents, die sog. "drug-eluting stents" (DES), haben die Restenoserate und damit die Notwendigkeit einer erneuten Revaskularisation nach perkutaner koronarer Intervention (PCI) um 50-71% gesenkt. Sie werden zunehmend bei anatomisch schwierigen Verhältnissen, wie langen, dünnkalibrigen Gefäßen, Totalverschlüssen und Bifurkationsstenosen, eingesetzt. Eine seltene, jedoch folgenschwere Komplikation der Stenteinlagen ist die Stentthrombose, eine partielle oder vollständige Obstruktion des Implantats. Die zunehmend komplexen Interventionen mittels DES, die potentiell prothrombotische Wirkung der antiproliferativen Substanzen und die verlangsamte Endothelialisierung verlängern und erhöhen theoretisch das Stentthromboserisiko nach Implantation eines DES. Eine 1-jährige doppelte plättchenhemmende Therapie wird deshalb zur Nachbehandlung empfohlen. Für den Nutzen einer routinemäßigen doppelten plättchenhemmenden Therapie über 1 Jahr hinaus fehlen zurzeit die Grundlagen. Nichtkardiale chirurgische Eingriffe sollten für 1 Jahr aufgeschoben werden oder nach Möglichkeit unter dem Schutz von Acetylsalicylsäure durchgeführt werde

Carotid artery stenting vs. endarterectomy

Randomized clinical trials have demonstrated that carotid endarterectomy (CEA) is superior to medical management for stroke prevention in patients with symptomatic and, to a lesser degree, asymptomatic internal carotid artery stenosis. However, large-scale registries have shown that the adverse event rates following CEA are commonly higher than observed in the trials. In the last decade, carotid artery stenting (CAS) has emerged as a less invasive alternative to surgery. In order to address the efficacy of CAS, we performed a meta-analysis of 10 randomized trials comparing CAS with CEA in 4648 mainly symptomatic patients. The analysis showed that CAS was associated with a statistically significant increased death or stroke rate at 30 days compared with CEA (odds ratio 1.60, 95% confidence interval 1.26-2.02). However, most of the trials had inadequate requirements in terms of endovascular expertise and did not mandate the use of emboli protection devices. Beyond 30 days, long-term follow-up of the trials previously reported suggest that both revascularization techniques are equivalent in terms of stroke prevention. Conversely, large-scale high-quality CAS registries—mostly with independent neurological assessment and clinical event committee adjudication—have reported results in the range of current recommendation for CEA in over 20 000 patients, despite the fact that the majority of patients were at high risk for surgery. Until further data become available, the performance of CAS should be limited to protocols or centres of excellence and targeted especially to patients at high risk for surger

Percutaneous coronary intervention in diabetic patients with non-ST-segment elevation acute coronary syndromes

Key pathophysiologic mechanisms of diabetes-related coronary disease include inflammation and a prothrombotic state. In the setting of non-ST-segment elevation acute coronary syndromes diabetic patients are at high risk for subsequent cardiovascular events. At the same time, they derive greater benefit than non-diabetic counterparts from aggressive antithrombotic therapy, early coronary angiography, and stent-based percutaneous coronary intervention. The mainstays of antithrombotic therapy for diabetic patients undergoing percutaneous revascularization include aspirin, clopidogrel, platelet glycoprotein IIb/IIIa receptor antagonists, and heparin or low-molecular-weight heparin. Despite dramatic reduction in restenosis conferred by drug-eluting stents, diabetic patients remain at increased risk for repeat revascularization. More efforts are needed both in terms of local drug elution as well as systemic pharmacologic therapies to further contain the excessive neointimal proliferation that characterizes the diabetic response to vascular injur

Carotid artery stenting: an update

In patients with carotid disease, the purpose of carotid artery revascularization is stroke prevention. For >50 years, carotid endarterectomy has been considered the standard treatment for severe asymptomatic and symptomatic carotid stenoses. Carotid artery stenting (CAS) has emerged in the last 15 years as minimally invasive alternative to surgery. However, the value of the endovascular approach in the management of carotid disease patients remains highly controversial. The aims of this review are to elucidate the current role of CAS, to describe the major technology advancements in the field, and to speculate about the future of this therap

Current concepts on coronary revascularization in diabetic patients

Diabetic mellitus (DM) patients with coronary artery disease (CAD) are at higher risk of cardiovascular events compared with non-DM individuals. While aggressive cardiovascular prevention and adequate blood glucose control remain cornerstones of therapy, the decision when and how to proceed to coronary revascularization in an individual DM patient should be based on the extent of CAD, ischaemic burden, ventricular function, as well as comorbidities. While in patients with stable symptoms, moderate CAD on coronary angiography and preserved left ventricular function a conservative strategy may be a valuable initial strategy, in patients with acute coronary syndromes (ACS) an early invasive approach should be favoured. The revascularization strategy for DM patients with complex multivessel CAD should be discussed within a heart team consisting of cardiologists, cardiac surgeons, and anaesthesiologists. In general, the threshold for coronary artery bypass surgery (CABG) should be lower for DM than for non-DM individuals. In patients undergoing percutaneous coronary intervention, the use of drug-eluting stents (DES) and—in the setting of ACS—of potent platelet inhibitors, such as prasugrel or ticagrelor, should be favoured. In the near future, multiple strategies may further favourably impact the prognosis of DM patients undergoing coronary revascularization. These include alternative antiplatelet agents such as thromboxane receptor inhibitors, the broad use of second generation DES, and possibly the implantation of bioresorbable stents. Coronary artery bypass surgery outcomes may also further improve by wide implementation of arterial revascularization, reduction in perioperative stroke by avoiding clamping of the aorta, reduction in wound infection by minimally invasive techniques, and optimization of post-operative medical managemen