Revascularization

Direct laser-assisted myocardial revascularization (DMR) is an approved technique in the US, Europe, and parts of Asia to create numerous myocardial channels. This results in the induction of a massive inflammatory reaction, which in turn induces angiogenesis. The other FDA-approved pro-angiogenic therapy is the use of recombinant human platelet-derived growth factor (Regranex) for use in the treatment of diabetic neuropathic foot ulcer s. 

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... 

Direct Fibrinolytics Alfimeprase is a recombinant tmncated form of fibrolase, a fibrinolytic zinc metalloproteinase isolated from the venom of the Southern copperhead snake. It degrades fibrin directly and achieves thrombolysis independent of plasmin formation. This may result in faster recanalization and a decreased risk of hemorrhagic conversion. The initial data on the safety and efficacy of alfimeprase in peripheral arterial occlusion disease appeared very promising, but recent communication from the sponsor revealed that the phase III trials of the drug in peripheral arterial disease and catheter obstruction (NAPA-2 and SONOMA-2) failed to meet their primary and key secondary endpoints of revascularization. A trial for I AT in acute stroke (CARNEROS-1) is planned to begin soon. 

Self-expanding stents with a higher radial force (e.g., WingSpan, Boston Scientific Corp.) will probably play a key role in acute stroke cases related to intracranial atherosclerotic disease. Antegrade flow is essential for the maintenance of vascular patency, as particularly evident in patients with severe proximal stenoses who commonly develop rethrombosis after vessel recanalization. Furthermore, stenting of the proximal vessels may be required in order to gain access to the intracranial thrombus with other mechanical devices or catheters. In a recent series, 23 of 25 patients (92%) with acute n = 15) or subacute n = 10) ICA occlusions were successfully revascularized with this technique. " ... 

The Penumbra stroke system (Penumbra Inc., San Leandro, CA) includes two different revascularization options (1) thrombus debulking and aspiration may be achieved by a reperfusion catheter that aspirates the clot while a separator device fragments it, and (2) direct thrombus extraction may be performed by a ring retriever while a balloon guide catheter is used to temporarily arrest flow. This system has been tested in a pilot trial in Europe. Twenty patients (mean NIHSS 21) with a total of 21 vessel occlusions (7 ICA, 5 MCA, and 9 Basilar) were treated up to 8 hours after symptom onset. Recanalization prior to lA lysis was achieved in all cases (48% TIMI 2 52% TIMI 3). Seven patients were also treated with lA UK or rt-PA. Good outcome at 30 days (defined as mRS < 2 or NIHSS 4-point improvement) was demonstrated in 42%. The mortality rate was 45%, but there were no device-related deaths. There was one asymptomatic SAH and three symptomatic ICHs. A prospective, single-arm, multicenter trial is being conducted in the United States and Europe currently. 

Hill MD, Barber PA, Demchuk AM, Newcommon NJ, Cole-Haskayne A, Ryckborst K, Sopher L, Button A, Hu W, Hudon ME, Morrish W, Frayne R, Sevick RJ, Buchan AM. Acute intravenous-intra-arterial revascularization therapy for severe ischemic stroke. Stroke 2002 33 279-282. 

Fitzsimmons BF, Becske T, Nelson PK. Rapid stent-supported revascularization in acute ischemic stroke. Am J Neuroradiol. 2006 27 1132-1134. 

Jovin TG, Gupta R, Uchino K, Jungreis CA, Wechsler LR, Hammer MD, Tayal A, Horowitz MB. Emergent stenting of extracranial internal carotid artery occlusion in acute stroke has a high revascularization rate. Stroke 2005 36 2426-2430. 

Wylie EJ, Hein ME, Adams JE. Intracranial hemorrhage following surgical revascularization for treatment of acute strokes. J Neurosurg 1964 21 212-215. 

Diaz EG, Ausman JI, Mehta B, Dujovny M, de los Reyes RA, Pearce J, Patel S. Acute cerebral revascularization. J Neurosurg 1985 63 200-209. 

Number of markers and 14-d risk of death, myocardial infarction, or urgent revascularization... 

Coronary angiography detects the location and degree of coronary atherosclerosis and is used to evaluate the potential benefit from revascularization procedures. Stenosis of at least 70% of the diameter of at least one of the major epicardial arteries on coronary angiography is indicative of significant IHD. 

Once the diagnosis of IHD is established in a patient, the clinician should provide counseling on lifestyle modifications, institute appropriate pharmacologic therapy, and evaluate the need for surgical revascularization. The major goals for the treatment of IHD are to ... 

Elevated homocysteine concentrations have been associated with an increased risk for cardiovascular disease in both epidemiologic and clinical studies.43 Several studies have evaluated the benefit of lowering homocysteine levels with folic acid supplementation. One study reported a reduction in major cardiac events with the combination of folic acid, vitamin B12, and vitamin B6 following PCI.44 However, a more recent study found an increased risk of instent restenosis and the need for target-vessel revascularization with folate supplementation following coronary stent placement.45 The role of folate in the management of IHD is currently unclear. 

Because reinfarction and death are major outcomes following ACS, therapeutic strategies to reduce morbidity and mortality, particularly utilization of coronary angiography, revascularization, and pharmacotherapy, will have a significant impact on the social and economic burden of CHD in the United States. 

Initiate pharmacotherapy for non-ST-segment elevation ACS based upon patient risk evaluate moderate and high-risk patients for early angiography and revascularization... 

High-risk NSTE ACS patients should undergo early coronary angiography (within 24 to 48 hours) and revascularization if a significant coronary artery stenosis is found. Moderate-risk patients with positive biochemical... 

In patients with NSTE ACS, clinical practice guidelines recommend either PCI or coronary artery bypass grafting revascularization as an early treatment for high-risk patients, and that such an approach also be considered for moderate-risk patients. An early invasive approach results in fewer Mis, less need for revascularization procedures over the next year after hospitalization, and lower cost than the conservative medical stabilization approach. 

For patients treated with fibrinolytics and in those receiving no revascularization therapy, clopidogrel either 75 mg or 300 mg on day 1 followed by 75 mg once daily should be given for at least 14 to 28 days in addition to aspirin. 

Administration of tirofiban or eptifibatide is recommended for high-risk NSTE ACS patients as medical therapy without planned revascularization. 

For patients with NSTE ACS undergoing planned early angiography and revascularization with PCI, UFH, LMWH (enoxaparin), fondaparinux, or bivalirudin should be administered. Therapy should be continued for up to 48 hours for UFH, until the patient is discharged, or a maximum of 8 days for either enoxaparin or fondaparinux, and until the end of the PCI or angiography procedure (or up to 42 hours after PCI) for bivalirudin. 

For patients with STEMI treated medically without revascularization, clopidogrel can be given for 14 to 28 days. If a stent has been implanted, clopidogrel can be continued for up to 12 months in patients at low risk for bleeding. 

Pentoxifylline (Trental) or cilostazol (Pletal) may be useful in selected patients. Revascularization is successful in selected patients. 

Morice MC, Serruys PW, Sousa JE, et al. A randomized comparison of a sirolimus-eluting stent with a standard stent for coronary revascularization. N Engl J Med 2002 346 1773-1780. 

Myocardial ischemia and infarction cause abnorma myocardial metabolism, decreased left ventricular (LV) systolic function, diastolic dysfunction, congestive heart failure, and decreased survival. Consequently, revascularization techniques, either surgical or catheter based, have become integral to treatment of severe ischemic heart disease. 

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