Indications of Angioplasty 1. To be candidate for revascularization procedure, one must have symptomatic or objective signs of ischemia. 2. Indications for PTCA or CABG may vary from one center to another according to experience, skills and results. 3. Definite indications for CABG: LM disease and 3 VD with proximal stenosis. 4. Definite indications for PTCA: SVD (apart from ostial LAD), with type A or B1 lesion.
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Indications of Angioplasty 1. To be candidate for revascularization procedure, one must have symptomatic or objective signs of ischemia. 2. Indications.
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Indications of Angioplasty
1. To be candidate for revascularization procedure, one must have symptomatic or objective signs of ischemia.
2. Indications for PTCA or CABG may vary from one center to another according to experience, skills and results.
3. Definite indications for CABG: LM disease and 3 VD with proximal stenosis.
4. Definite indications for PTCA: SVD (apart from ostial LAD), with type A or B1 lesion.
• Are there still contra indications for angioplasty??– Almost every lesion can be treated
• Who needs surgery ??– Incomplete revascularisation– Mortality studies
New technologies were created to improve the PTCA balloon.
• Major limitations of PTCA– acute vessel closure during intervention– restenosis
• Intracoronary stenting has shown clinical efficacy
• First stents implanted in 1986
• High frequency of complications:– subacute stent thrombosis– stent misplacement– suboptimal deployment– bleeding complications
• In 1994 results of BENESTENT and STRESS were published showing a reduction in restenosis rate
• At that time early stent thrombosis remained a major drawback– Double antiplatelet therapy– High-pressure deployment
• CURRENT INDICATIONS OF STENTING:
– elective stenting : primary prevention of restenosis
– elective stenting : secondary prevention of restenosis
– bail-out stenting : management of acute or threatened vessel closure
• CURRENT INDICATIONS OF STENTING:
– saphenous-vein-graft disease– acute myocardial infarction– chronic total occlusion
• UNTIL NOW NO SCIENTIFIC PROOF EXISTS FOR STENT PLACEMENT IN:
– suboptimal angioplasty– long or diffuse disease or both– small vessels– aorto-ostial disease– bifurcation lesions
COMPLICATIONS OF ANGIOPLASTY
• The major complications of coronary interventions are:– death ( 0.5% to 1 % )– Q-wave myocardial infarction ( 1% to 3% )– need for emergent surgical coronary
revascularization ( about 1 % )
COMPLICATIONS OF ANGIOPLASTY
• Complications usually results from acute occlusion of the target vessel– causes include
• dissection• thrombosis• embolism• spasm
• Stenting is an effective therapy in treating acute and threatened coronary occlusion initiated by dissection
Other complications
• Vascular problems
• Rhythm disturbances
• Cholesterol embolization
• Cerebral problems
Evolution of PCI results
CARPORT VELVET
1987 2000
Failed PTCA 7.0% 0.0%
Death 1.4% 1.6%
MI 6.0% 0.8%
CABG 8.0% 0.0%
RePTCA 18.0% 2.5%
Angina at FU 26.0% 5.0%
Symptom free 56.0% 89.3%
PTCA results according toclinical presentation
RISK OF COMPLICATION IS INCREASED WHEN:. Multivessel disease. Old age. Diabetes. Unstable angina or recent MI ( < 3 Weeks). LV failure. Women. Prior bypass coronary surgery
1. Angiographic assessment : pre - post - (3 - 6 mths)
Quantitative angiography : pre PTCA : 65 ± 10% post PTCA : 30 ± 10% F.U. : 45 ± 10%
2. Functional assessment
- Translesional gradient after adenosine (FFR)- Coronary flow reserve : Doppler- ETT pre post (24 - 48 h. or 1 week) F.U. (6 w - 3 mths)- Perfusion scan pre - 3 weeks - F.U. (3 mths)
3. IVUS assessment : pre - post
- Characterization of arterial wall and atheromatous plaque - assessment of PTCA result, stent expansion
MECHANISMS OF RESTENOSIS• Thrombosis (acute and subacute closure).• Early and late recoil (Balloon Angioplasty).• Neointimal proliferation (Stent, DCA,
Rotablator, Laser).
IVUS data:
Balloon PCI : 15% of restenosis due to tissue ingrowth 85% due to geometric remodeling
• Stents will prevent vascular recoil and remodelingStents will prevent vascular recoil and remodeling • Active therapeutic agent (radiation or drug) is required Active therapeutic agent (radiation or drug) is required to block neointimal hyperplasiato block neointimal hyperplasia
• Drug eluting stents: ‘the holy grail’??• So far only RCT data in ‘selected’ cohorts
of patients• The results of larger randomized safety and
cost-effectiveness trials are awaited (no angio fu...)
• Long term follow-up is needed• Drastic changes in policies and strategies of
revascularization have already occurred... too soon?
Coronary Artery Bypass Graft SurgeryCoronary Artery Bypass Graft Surgery
• Coronary artery bypass grafts (CABG) are intended to shunt blood from the aorta to the coronary artery, beyond an area of severe narrowing or occlusion
• CABGs can be constructed from veins or arteries
• Saphenous vein grafts (SVG) are conduits made by harvesting a piece of vein from the patient’s leg and attaching it between the aorta and coronary artery
• Arterial bypass grafts involve re-routing an artery from its normal course and attaching it to the coronary artery– Internal Mammary Artery– Gastroepiploic Artery– Radial Artery
Coronary Artery Bypass Graft SurgeryCoronary Artery Bypass Graft Surgery
• 1964: first aortocoronary saphenous vein graft implantation in a human by Garrett
• Subsequent pioneering work of Favaloro at Cleveland Clinic
• Effective treatment for intractable angina pectoris and a mean of improving long–term prognosis in certain patients subgroups.
• Despite its dramatic benefits it remains a palliative procedure due to accelerated atherosclerosis in the grafted saphenous vein conduits.
SVG Anatomy & PhysiologySVG Anatomy & Physiology
ProximalAnastamosis
VeinGraftBody
DistalAnastamosis
• Vein grafts are merely conduits – lack vascular tone found in
arteries– arterial bypass grafts (IMA) have
superior patency• preferred CABG for the LAD
• Vein grafts are prone to developing obstructive disease
• SVG disease is morphologically different depending on its location in the vein graft
Current Medical State of SVG DiseaseCurrent Medical State of SVG Disease
• Average lifespan for a vein graft is 5-10 years– 50% of SVGs will be occluded within 10 years– 75% will develop severe narrowing in same period
• SVG lesions presenting within the first year after surgery are typically caused by intimal hyperplasia– respond well to balloon dilatation
• Late vein graft stenoses are more commonly caused by diffuse atherosclerosis– friable plaque and thrombus tend to fragment and
embolize into distal coronary vessels
Coronary Artery Bypass Graft SurgeryCoronary Artery Bypass Graft Surgery
• Despite vein grafts are inferior to arterial grafts , they are still used :– Multivessel disease– Subclavian artery or internal mammary artery
disease– Emergency situations
Pharmacologic therapy:acute coronary syndromes
Acute myocardial infarction• Caused by an occlusion of a coronary
artery, mostly by a thrombus
• Clinically : longstanding, intense, oppressive chest pain, not responding on nitrates
Clinical presentation : myocardial necrosis
ECG features of myocardialischemia and infarction
Diagnosis• ECG
(ST elevation vs. Non ST elevation MI) • Enzymes
Troponines: highly specific but positive after 4 hoursCK-MB: not so specific and also positive after 4 hoursMyoglobine: low specificity, positive after 2-3 hours
• Echoif ECG is negative, Echo can show areas of hypo/akinesia
• Angiofinal “confirmation” of a stenotic/occluded vessel
Supportive therapy
• For all:– Rhythm control (continuous monitoring)– Intravenous line (glucose 5 %)– Oxygen (2 tot 4 l)– Pain control
• Pain killers: morphine• Beta-blockers• Sedation
– Aspirin at least 300 mg
Real treatment
• Open the occluded vessel as soon as possible
» Fibrinolysis
» PCI
Treatment of AMI30-day mortality based on level of risk
Low Intermediate High
2.9%
8%
12.7%
7.9%
13.1%
24.1%
%
PCR Lysis
PCAT
Equivalent time to reperfusion with fibrinolysis or primary PCI
WW3215
Reperfusion time(60’)
Start Tx(60’)
reperfusion time(30’)
Start Tx(30’)
TIMI 3 rateTreatment
Lysis
PTCA
Time0’ 90’
95%
70%
Fibrinolysis• Dissolution of fibrin thrombi
– Streptokinase first studied (90 minutes infusion)– tPA (alteplase) 1 hour infusion– rPA (reteplase) 2 boluses every 30 minutes– TNK (tenecteplase) 1 single bolus
• Works only in the first 6-12 hours after AMI– the sooner the better
• Risks: – Bleeding (cerebral ~1%)– Reocclusion of the artery
Primary PCI
• Immediate idea on the whole coronary anatomy• Better en faster reperfusion• Stents reduce reocclusion and restenosis• Glycoprotein receptor blockers (abciximab)