Role of Intravascular Ultrasound in Managing a Rare Case of Delayed Stent Deformity.

Delayed stent deformity is a very rare complication. We attempted to dilate the lumen within the crushed stent, but were unsuccessful even after laser atherectomy. At this point, we opted to place a new stent within the deformed old stent. In this case, intravascular ultrasound was extremely useful in guiding its diagnosis and management.

Ubiquitous Nature of Distal Athero/Thromboembolic Events during Lower Extremity Atherectomy Procedures Involving the Superficial Femoral Artery.

This study aims to evaluate occurrence, size, composition, and clinical significance of embolized debris during superficial femoral artery atherectomy using all commercially available atherectomy devices. Distal athero/thromboembolic events (DATE) are a universal phenomenon in lower extremity atherectomy procedures (LEAPs) due to the sheer volume of atheroma and the thrombus burden in peripheral arterial disease. Some of these events can be clinically significant. We prospectively gathered clinical and histopathological data on all commercially available atherectomy devices by using embolic protection devices (EPD) in every case. After intervention, the contents of EPD were examined both microscopically and macroscopically. Data from 59 consecutive patients undergoing LEAP were analyzed. DATE occurred 100% of the time. The composition of particulate debris varied with the device used. Grossly visible agglomerated debris was captured by the filter in the majority of patients 54/59 (91.5%). Clinically significant debris, defined by the Preventing Lower Extremity Distal Embolization Using Embolic Filter Protection registry as particle diameter > 0.2 cm, was found in 33/59 (56%) patients. The size of captured debris particles ranged from 0.1 to 2.4 mm. While DATE occurred in all patients, clinically significant DATE occurred in 56% patients undergoing LEAP regardless of the atherectomy device. In spite of a large fraction of the clinically significant debris occurring on our routine dual antiplatelet regimen, no patient suffered an amputation. Although DATE was prevented by the use of EPD in all 59 cases, more data are needed to determine whether the use of EPD translates into a long-term clinical benefit. Use of EPD and optimal thromboprophylaxis should be considered in patients, especially in the setting of compromised distal runoff.

Analysis of particulate debris after superficial femoral artery atherectomy.

PURPOSE: To evaluate the occurrence, size and composition of embolized debris captured during routine directional atherectomy using the SilverHawk device. METHODS: 15 consecutive eligible patients with a nonocclusive superficial femoral artery (SFA) were enrolled. Patients were included if they were > 18 years of age and had > or = 70% stenosis in the SFA. All lesions underwent plaque excision with the SilverHawk atherectomy device. A FilterWire EZ was used for distal protection and retrieval of embolized material. Specimens were collected separately from the filter basket and the SilverHawk atherectomy device's nosecone and were studied by a pathologist for number, size and composition. RESULTS: Visible debris captured in the filter was found in the majority of patients 14/15 (93%). Clinically-significant debris was found in 7/15 (47%) patients. The proportion of captured debris ranged from 0.1-0.4 cm. Microscopy revealed that the shaved particles consisted predominantly of collagen, fibrin, lipid-laden macrophages, cholesterol and calcium. Analysis of the embolized material revealed a different composition, mostly consisting of collagen with fibrosis, cholesterol and macrophages. CONCLUSION: In this single-center comparative study we have shown that during SilverHawk atherectomy of SFA lesions, distal embolization is universal. The debris captured in the filter is different in overall composition from the captured material in the nosecone of the SilverHawk device. Debris large enough to cause clinically-significant embolization, no-reflow and ischemia following SFA interventions occurred in nearly 50% of cases.

Primary percutaneous coronary intervention for ST-elevation myocardial infarction using an intravenous and subcutaneous enoxaparin low molecular weight heparin regimen.

BACKGROUND: Enoxaparin use in PCI has been investigated, however its role in primary PCI is less known. OBJECTIVE: To evaluate the role of combination IV + SC enoxaparin in primary PCI in STEMI. METHODS: 83 consecutive patients with STEMI who underwent primary PCI between January 1, 2005 and January 15, 2008 were included. Anticoagulation was based on our institution's STEMI protocol; either IV + SC enoxaparin, or IV unfractionated heparin (UFH). Clinical endpoints included MACE, bleeding and net adverse cardiac events (NACE). RESULTS: 45 patients received UFH and 37 received IV + SC enoxaparin. There was no difference in the rate of mortality, MACE, or NACE. There was a trend toward more TIMI major and GUSTO moderate and severe bleeding in the UFH group. CONCLUSIONS: Application of IV + SC enoxaparin strategy for primary PCI in STEMI appears both safe and efficacious. A prospective randomized trial will be necessary to evaluate the safety and efficacy more thoroughly.