Angioplasty

Economic Aspects. The cardiovascular devices market is estimated to be approximately 2.9 biUion annually on a worldwide basis. This market can be further segmented as follows angiography and angioplasty, 644 x 10 arrhythmia control, 1500 x 10 cardiovascular surgery, 700 x 10 cardiac assist (intra-aortic balloon pump), 80 x 10 and artificial hearts, which are experimental. 

Laser ablation systems hold considerable promise if restenosis (reblocking of the arteries) rates are reduced. The rate as of 1995 is 30%, typically within six months. Mechanical or atherectomy devices to cut, shave, or pulverize plaque have been tested extensively in coronary arteries. Some of these have also been approved for peripheral use. The future of angioplasty, beyond the tremendous success of conventional balloon catheters, depends on approaches that can reduce restenosis rates. For example, if appHcation of a dmg to the lesion site turns out to be the solution to restenosis, balloon catheters would be used for both dilating the vessel and deUvering the dmg. An understanding of what happens to the arterial walls, at the cellular level, when these walls are subjected to the various types of angioplasty may need to come first. 

Fluosol-DA, a 20% by weight emulsion, has been Hcensed for use ia coronary angioplasty. As of 1991, this product was available through the U.S. Food and Dmg Administration (FDA) for compassionate use. 

Intraaortic balloon Angioplasty catheter Vascular grafts Sutures... 

GPIIb/IIIa antagonists have to be administered parenterally. They are currently used prophylactically during intracoronary interventions such as percutaneous transluminal revascularization with balloon angioplasty or intracoronary stenting, as well as to treat acute coronary syndromes like unstable angina and acute myocardial infarction. The main complications... 

Abciximab Glycoprotein llb/llla antibody Coronary angioplasty... 

Percutaneous coronary intervention (PCI) is one of a host of techniques performed by using a catheter inserted via a major limb artery that aims to relieve nanowing of coronary arteries. For example, percutaneous transluminal coronary angioplasty (PTCA) is the classic PCI that uses a catheter-directed balloon to dilate a stenotic coronary artery, and more recent PCIs include stent implantation, rotational atherectomy, and laser angioplasty. 

The PDE3 inhibitor, cilostazol, has been used as an antithrombotic agent and is currently being used in patients being treated for intermittent claudication. Cilostazol is also used for the prevention of restenosis after treatments such as angioplasty. Another PDE3 selective inhibitor, milrinone, has been used in the treatment of congestive heart failure. Milrinone also has been shown to increase the conductance of the CFTR transporter in vitro. 

In a prospective, open-label study, Hill et al. assessed the feasibility of a bridging approach using full-dose IV rt-PA. Following IV infusion of 0.9 mg/kg rt-PA, six patients underwent lAT with rt-PA (maximum dose 20 mg) and one underwent intracranial angioplasty. TIMI 2 or 3 recanalization was achieved in three of these patients. There were no symptomatic ICHs. 

The data for the use of GP Ilb/Illa inhibitors in conjunction with lAT are even more scant, and are limited to case reports. Intravenous abciximab has been successfully used as adjunctive therapy to lA rt-PA or UK in cases of acute stroke. Desh-mukh et al. reported on 21 patients with large vessel occlusion refractory to lAT with rt-PA who were treated with IV and/or lA abciximab, eptifibatide, or tirofiban. Twelve patients also received IV rt-PA and 18 patients underwent balloon angioplasty. Complete or partial recanalization was achieved in 17 of 21 patients. Three patients (14%) had asymptomatic ICH, but there were no cases of symptomatic ICH. Mangiafico et al. described 21 stroke patients treated with an intravenous bolus of tirofiban and heparin followed by lA urokinase. Nineteen of these patients also underwent balloon angioplasty. TIMI 2-3 flow was achieved in 17 of 21 patients. ICH occurred in 5 of 21 patients (3 symptomatic ICH and 2 SAH), and was fatal in 3... 

FIGURE 4.2 Seventy-three-year-old female with sudden right hemiparesis, left facial weakness, dysarthria, nausea, and downheat nystagmus. Posterior circulation angioplasty demonstrated occlusion of the proximal hasilar artery (arrows— a and b). Note the retrograde opacification of the superior cerebellar arteries through postero-inferior cerebellar to superior cerebellar arteries collaterals (b). 

FIGURE 4.2 (Continued) A compliant balloon was used to perform angioplasty (c). Postangioplasty angiogram demonstrated complete recanalization of the basilar artery and its major branches (d and e). MRI performed 2 days later demonstrated only small areas of infarction in the cerebellar hemispheres (arrows—f and g) but no brainstem or occipital infarcts. 

The In-Time Retriever (Boston Scientific, Natick, MA) has four to six wire loops and tends to bow when opened but has no specific opening to capture the embolus. This device has been successfully used in a case of an MCA occlusion resistant to thrombolytics and balloon angioplasty, as well as in cases of basilar occlusion. The TriSpan (Boston Scientific, Natick, MA), a neck bridge device consisting of three nitinol loops originally designed to treat wide-necked aneurysms, has also been used to treat basilar occlusions. ... 

Ueda T, Hatakeyama T, Kohno K, Kumon Y, Sakaki S. Endovascular treatment for acute thrombotic occlusion of the middle cerebral artery local intra-arterial thrombolysis combined with percutaneous transluminal angioplasty. Neuroradiology 1997 39 99-104. 

Ueda T, Sakaki S, Nochide I, Kumon Y, Kohno K, Ohta S. Angioplasty after intra-arterial thrombolysis for acute occlusion of intracranial arteries. Stroke 1998 29 2568-2574. 

Nakano S, Iseda T, Yoneyama T, Kawano H, Wakisaka S. Direct percutaneous transluminal angioplasty for acute middle cerebral artery trunk occlusion an alternative option to intra-arterial thrombolysis. Stroke 2002 33 2872-2876. 

Abou-Chebl A, Bajzer CT, Krieger DW, Furlan AJ, Yadav JS. Multimodal therapy for the treatment of severe ischemic stroke combining GPEh/IIIa antagonists and angioplasty after failure of thrombolysis. Stroke 2005 36 2286-2288. 

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