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We sought to determine the clinical significance of aspirin resistance measured by a point-of-care assay in stable patients with coronary artery disease (CAD).We used the VerifyNow Aspirin (Accumetrics Inc, San Diego, Calif) to determine aspirin responsiveness of 468 stable CAD patients on aspirin 80 to 325 mg daily foror =4 weeks. Aspirin resistance was defined as an Aspirin Reaction Unitor =550. The primary outcome was the composite of cardiovascular death, myocardial infarction (MI), unstable angina requiring hospitalization, stroke, and transient ischemic attack.Aspirin resistance was noted in 128 (27.4%) patients. After a mean follow-up of 379+/-200 days, patients with aspirin resistance were at increased risk of the composite outcome compared to patients who were aspirin-sensitive (15.6% vs 5.3%, hazard ratio [HR] 3.12, 95% confidence intervals [CI], 1.65-5.91, P.001). Cox proportional hazard regression modeling identified aspirin resistance, diabetes, prior MI, and a low hemoglobin to be independently associated with major adverse long-term outcomes (HR for aspirin resistance 2.46, 95% CI, 1.27-4.76, P = .007).Aspirin resistance, defined by an aggregation-based rapid platelet function assay, is associated with an increased risk of adverse clinical outcomes in stable patients with CAD.

OBJECTIVE Current arterial transfer functions have low capability in predicting aortic augmentation index (AIx) from radial pulse contour (RPC), because of the difficulty in accurately identifying the merging point (inflection point) in the derived aortic pulse contour (APC). We hypothesize that the formation time between each characteristic wave in APC is about one-third of ejection duration (ED/3). We sought to assess the accuracy of ED/3 in identifying the merging point in APC as compared to the conventional differential method. In addition, we sought to derive the AIx from RPC based on an arterial transfer function and the ED/3 method. METHODS APC and RPC sequences were measured digitally and simultaneously in 60 subjects (37 males; aged 60 +/- 10 years). An ensemble-averaged RPC-to-APC transfer function was determined from 30 randomly selected subjects and was used to derive APC sequences in the 30 additional subjects. The accuracy of AIx predicted from RPC was determined. RESULTS In patients with a clearly identifiable merging point in APC, the ED/3 method identified the merging point of measured APC within 1.97 +/- 0.60 ms of that identified by the conventional differential method, with identical AIx. The AIx and merging point of derived APC using the ED/3 method were also within 0.22 +/- 1.01% and 1.81 +/- 1.64 ms, respectively, of those of the measured APC using the conventional differential method. The accuracy of the predicted AIx was independent of age, sex, body-mass index and presence of hypertension. CONCLUSION In a quiet resting state, the ED/3 is an alternative method for identifying the merging point in APC. In conjunction with transfer-function technique, AIx can be derived accurately from RPC.

Previous studies have shown that more complete platelet inhibition improves the coronary flow reserve (CFR), a measure of microvascular integrity, in patients undergoing percutaneous coronary intervention (PCI). We hypothesized that patients with aspirin resistance would have impaired CFR after elective PCI. We used VerifyNow Aspirin to determine the response to aspirin in 117 consecutive patients who underwent elective single-lesion PCI. The assay results are expressed quantitatively in Aspirin Reaction Units based on the degree of platelet aggregation. All patients received a 300-mg loading dose of clopidogrel >12 hours before and a 75-mg maintenance dose the morning of PCI. CFR was estimated using the Thrombolysis In Myocardial Infarction frame count method. Of the 117 patients, 22 (18.8%) were aspirin resistant. The clinical, angiographic, and procedural characteristics of the aspirin-sensitive and -resistant patients were balanced. All patients underwent successful PCI with

The FilterWire EX is one of the filter protection devices developed as alternatives to balloon occlusion system for percutaneous coronary intervention. Its use has been recommended in vessels between 3.5 and 5.5 mm in diameter and no data are available on its use in smaller vessels. We evaluated the safety and feasibility of using FilterWire EX in native coronary arteries smaller than 3.5 mm. We successfully deployed and retrieved the FilterWire EX in 49 coronary arteries with a mean vessel diameter of 2.62 +/- 0.45 mm at device deployment. Reversible vasospasm was observed in 24 (50%) vessels, coronary flow was temporarily reduced in 22 (44.9%), and distal embolization was noted in 2 (4%). There was no vessel dissection induced by the device. These data suggest that it is safe and feasible to use the FilterWire EX in small coronary arteries.

Patients with chronic renal failure, because of concomitant conventional cardiovascular and uremia-associated risk factors, are at risk of developing diffuse and accelerated atherosclerosis involving both the coronary and peripheral territories. We report an end-stage renal failure patient with a history of coronary artery bypass surgery who developed both angina and dizziness during hemodialysis via a left forearm arteriovenous fistula. Magnetic resonance imaging diagnosed the presence of significant subclavian artery stenosis. The patient then underwent successful percutaneous stenting of the left subclavian artery. His angina and dizziness symptoms resolved subsequently. Catheter Cardiovasc Interv 2004;62:244–248. © 2004 Wiley-Liss, Inc.

Subclavian artery lesion that is associated with low complication rate could be treated by percutaneous intervention effectively. However, the success of endovascular therapy for occlusive lesion may be limited by failure to cross with a guidewire. We describe the use of a system using optical coherence reflectometry for navigation and radiofrequency ablation to enable wire passage through subclavian artery occlusion that could not be crossed by conventional guidewires.