Contemporary antithrombotic strategies in patients undergoing coronary stent implantation

The number of annual stenting procedures has been increasing at a rapid pace since coronary stents were first used in clinical practice just over a decade ago. Subacute stent thrombosis, which usually has serious clinical consequences, plagued the stent early experience despite intense anticoagulation therapy. The reduction of stent thrombosis was among the factors that contributed to stent growth and widespread acceptance in recent years. This was the result of improved implantation techniques, advances in adjunctive pharmacotherapy and evolution in stent designs, delivery systems and non-thrombogenic coatings. However, novel designs and materials customized for particular lesion types and newer anti-restenotic treatments could influence stent thrombogenicity. Intravascular brachytherapy and drug-eluting stents have been shown to reduce the incidence of in-stent restenosis preventing cellular proliferation. However, by interfering with the re-endothelization process they may also increase the risk of stent thrombosis. To prevent a recrudescence of this feared complication, future research direction must focus on the hemocompatibility aspects of new technologies, along with further refinement of stent-deployment techniques and antithrombotic strategies

CT-scan, coronary angiogram and intravascular ultrasound for subclinical coronary artery disease detection

The absence of any chest discomfort and/or dyspnea on exercise may sometimes be misleading in coronary artery disease detection. Computed tomography (CT-scan) coronary imaging can detect early subclinical coronary disease, which might either impact on prevention and treatment of high-risk individuals or be helpful to assess progression of coronary artery disease. The case we present shows CT-scan superiority in isolated coronary artery disease evidence, when compared to conventional coronary angiogram, successfully confirmed by intravascular ultrasound (IVUS) examinatio

Applicazione percutanea di collagene (VASOSEAL): un\u2019efficace sistema di emostasi dopo cateterismo o procedure interventistiche per via arteriosa

Introduction. The widespread use of PTCA and complex percutaneous interventional techniques has significantly increased peripheral vascular complications prompting the development of innovative hemostatic closure devices. Methods. To evaluate the efficacy and safety of a bovine collagen plug (VasoSeal), we sealed 362 consecutive femoral artery puncture sites in 324 patients (240 males) (mean age 57.9 \ub1 11.3 years), who underwent interventional procedures or diagnostic catheterization during acute or chronic anticoagulant treatment. Results. Complete hemostasis was achieved in 2.31 \ub1 1.97 minutes in 342 cases (94.4%), with a mean activated clotting time at collagen deployment of 197 \ub1 56''. In 20 cases, mechanical arterial compression was needed in order to obtain vascular hemostasis (mean time: 44 \ub1 13 min). We observed 1 arteriovenous fistula and 1 acute arterial thrombosis (collagen related at surgical inspection) which underwent successful surgical treatment. Minor complications without clinical sequelae were: small hematomas in 13 cases (3.8%), 4 groin abscesses (1.1%) and 4 cases of lymphangitis (1.1%). Conclusions. Percutaneous collagen application at the femoral artery puncture site allows quick and effective hemostasis with low incidence of peripheral vascular complications following interventional percutaneous procedures or catheterization during anticoagulant treatment

Successful transcatheter management of Palmaz Stent embolization after superior vena cava stenting

A 34-year-old patient with benign superior vena cava syndrome (SVCS) was treated with thrombolytic therapy, balloon angioplasty, and placement of two peripheral Palmaz stents. Embolization of one stent to the right atrium occurred 10 min after successful implantation. This serious complication was successfully managed by percutaneous transcatheter technique with retrieval from the right atrium and subsequent deployment into the right external iliac vein of the lost stent. Complete resolution of SVCS symptoms occurred within 24 hr and moderate superior vena cava restenosis was successfully dilated 8 months later. At 12-month follow-up the patient continues to be asymptomatic

[Intravenous ultrasonography as a method for imaging the morphoanatomical effects of coronary angioplasty]

Despite the therapeutic success of percutaneous transluminal coronary angioplasty (PTCA), the mechanisms by which PTCA increase vessel luminal size remain uncertain. To better understand the transmural morphologic changes associated with PTCA of stenosed coronary arteries, we studied with a high-frequency intravascular ultrasound catheter 18 coronary artery segments in 18 patients following balloon angioplasty. High-quality cross-sectional images were obtained from 15 coronary sites without complications in all patients. Two distinctive morphologic features following balloon angioplasty were appreciated by intravascular ultrasound imaging. The first pattern, observed in 10 cases (67%), consisted of a stretched plaque without any evidence of dissection. The second pattern, found in 5 cases (33%), demonstrated a dissection of the plaque ranging from a radial tear with separation of the 2 ends of the plaque to an extensive dissection which, in 1 case, encompassed the entire circumference of the artery. Although angiography showed a good post-angioplasty result in all cases, intravascular ultrasound evidenced a large amount of residual atheroma occupying the artery cross-sectional area. In addition, this imaging modality revealed more often than angiography the presence of calcification and dissection. These data demonstrate that PTCA creates different morphologic patterns which are related to the mechanisms of lumen enlargement and that the coronary artery anatomy after dilatation is much more complex than that observed with angiography. This study confirms that intravascular ultrasound is a feasible and safe imaging modality which provides new valuable insight into the mechanisms by which angioplasty improves vessel patency

A new kaolin-based haemostatic bandage compared with manual compression for bleeding control after percutaneous coronary procedures

Bleeding and vascular access site complications are an important cause of morbidity after percutaneous femoral procedures. New haemostatic dressings have been developed to control heavy bleeding. To evaluate the efficacy of a new kaolin-based haemostatic bandage for femoral artery closure after diagnostic or interventional procedures compared with manual compression

Calcium-channel blockade with nifedipine and angiotensin converting-enzyme inhibition with captopril in the therapy of patients with severe primary hypertension

Nifedipine (10 mg qid) and captopril (25 mg qid) were tested alone and in combination in 14 patients suffering from severe primary hypertension. Each study period was of 1 week's duration. Circulatory response was evaluated through hourly pressure and pulse rate readings. The fall in pressure after oral nifedipine was maximal within 1 hr or less and was generally accompanied by palpitation and increase in pulse rate; with a six hourly dosing regimen the tendency of blood pressure to recover after each dose was interrupted by the next dose, so that values remained significantly reduced throughout the 24 hr, although pressure fluctuations were evident. Promptness of the antihypertensive action of captopril was similar, but the magnitude and the duration of the fall in pressure were less pronounced. When the converting-enzyme inhibitor was combined with the calcium-channel blocker, pressure fluctuations were not abolished, but the antihypertensive response was definitely enhanced, so that normal blood pressure was maintained for several hours during the day. Additional positive effects of captopril were mitigation of the heart rate reaction and prevention of the ankle pitting or edema elicited by nifedipine. A balance in arteriolar and venular dilatation promoted by captopril is the suggested mechanism for these effects. With the two-drug combination the function of the left ventricle was not reduced and possibly improved; blood urea nitrogen and serum electrolyte and creatinine concentration were not affected. Plasma renin activity increased with captopril and reverted toward baseline with the addition of nifedipine, suggesting an interference of the calcium-channel blocker with the release of renin