CC May 2017 Coronary Stents

echoecho's version from 2017-05-15 16:34


Question Answer
The adequate knowledge by the PCP, though not likely to guide initial therapy, can do what? patient understand the therapy and optimize medical management
*** What were the findings of the EXCEL trial where 1905 left main coronary artery disease (LMCAD) patients were randomized to either PCI with drug-eluding stents (Everolimus-eluding) or CABG? studies confirmed PCI with drug-eluding stents was not non-inferior to CABG in this subset of LMCAD patients 2) the 3-year revascularization rate was 5% higher in the PCI group 3) other adverse events like MI, bleeding and renal failure were 15% higher in patients who underwent CABG
What are cardiologists now offering to the LMCAD patients?offer PCI with drug-eluding stents anda to avoid the far more invasive CABG surgery
List the 5 different cardiac stents now available as of 2017?1) bare metal (BMS) 2) first generation drug eluding stents (G1-DES) 3) 2nd generation drug-eluding stents (G2-DES) 3) 3rd generation drug-eluding stents (G3-DES; e.g. SYNERGY) 4) 4th generation drug-eluding stent (G4-DES; e.g. Absorb GT-1)
Describe bare metal (BMS) stents as to material, polymer coating and type of drug-eluting?1) steel, cobalt chromium, platinum chromium 2) none 3) no
Describe 1st generation drug-eluting stents (G1-DES) as to material, polymer coating and type of drug-eluting?1) steel, cobalt chromium, platinum chromium 2) nonresorbable 3) Sirolimus or Paclitaxel over 2-4 weeks
Describe 2nd generation drug-eluting stents (G2-DES) as to material, polymer coating and type of drug-eluting?1) steel, cobalt chromium, platinum chromium 2) nonresorbable 3) Everolimus or Zotarolimus over 2-4 weeks
Describe 3rd generation drug-eluting stents (G3-DES) as to material, polymer coating and type of drug-eluting?1) platinum chromium 2) bioresorbable over 3 months 3) Everolimus
Describe 4th generation drug-eluting stents (G4-DES) as to material, polymer coating and type of drug-eluting?1) bioresorbable scaffolding reabsorbed by 36 months 2) bioresorbable over 3 months 3) Everolimus
How do cardiac stents differ?1) by the material from which the stent struts are constructed 2) the width of the struts 3) the presence of a polymer coating 4) the stents' ability to elude drugs into the surrounding vessel wall 5) the drug used
In 1993, what stents were first approved by the FDA? What were they made of? Are they coated or drug-eluting? 1) bare metal stents (BMS) 2) steel, cobalt chromium or platinum chromium 3) are not coated or drug-eluding
What is the most commonly used in PCI stenting procedures now?G2-DES
Presently, which stent has bioresorbed polymer coating with metal scaffolding staying in place?SYNERGY stent system approved by the FDA in 2015
In July 2016, the FDA approved the Absorb GT-1 Bioresorbable Vascular Scaffold by Abbott, describe this stent?it is a thicker stent than most drug-eluting stents, however, which limits the vessel in which it can be used and requires increased training and use of intravascular US before stent placement. It has bioresorbable scaffolding reabsorbed by 36 months and the polymer coating is bioresorbable over 3 months. It has Everolimus as it's drug-eluting drug
What two key stent-related complications provides insigh into the evolution of stents as adjunctive therapies to balloon angioplasty?1) stent thrombosis 2) stent restenosis
Define thrombosis in a cardiac stent?sudden appearance of thrombus in a previously widely patent vessel or stent, usually denoted clinically by sudden death or MI in a previously stable patient
Historically, trials with PCI and balloon angioplasty resulted in a ___ to ___% rate of acute vessel thrombosis, often resulting in emergent target vessel revascularization by CABG?6-10%
The high rate of this potentially catastrophic complication drove the Ned for the creation of stents, which can thrombosis but currently have rates of less then ___%?1%
Define stent thrombosis?1) either acute (within 24 hours or placement) 2) subacute (within 30 days) 3) late (within 1 year) 4) very late (> 1 year) 5) occurs roughly equally in all types of stents 6) event usually occurs w/in 30 days of stent placement 7) especially within 24-48 hours for bare metal stents (BMS)
List the risk factors for thrombosis?1) presence of acute coronary syndrome at time of placement 2) mutlivessel disease 3) longer length stents 4) small vessel caliber
*** What is the single best predictor of early and late stent thrombosis?premature discontinuation of dual antiplatelet therapy
What is stent restenosis?1) a gradual narrowing of the stent lumen that usually occurs 3-12 months after stent placement 2) occurs when vessel wall damage, thrombus formation and the presence of the stent causes the formation of a layer of tissue over the struts and tissue inside the stent (neointimal tissue proliferation) 3) unabated the process of restenosis peaks (minimizing the lumen) at 6-12 months and then steadily regresses
Which stent has the highest rate of significant restenosis requiring target vessel revascularization at a rate of about ___% at 1 year?14%
To combat this restenosis issue, what were introduced that reduced neointimal hyperplasi?polymer-coated, drug eluting stents with anti-inflammatory and immunosuppressive properties
Randomized trials have demonstrated a ___ to _________% reduction in target vessel revascularization when comparing G1-DES to BMS?50%; 70-%
What was improved with the G2-DES?1) smaller struts 2) easier delivery 3) reduction in vessel inflammation 4) faster healing/epithelialization
*** A recently published Norwegian Coronary Stent (NORSENT) trial compared second generation drug-eluting stents (G2-DES) vs. BME in 9000 patients with a primary endpoint of all-cause death and non fatal spontaneous MI and secondary endpoints of repeat revascularization, stent thrombosis and quality of life, all at 5 years of follow-up. What is the findings?1) slightly higher rates of revascularization were shown in the BMS arm (19.8% vs. 16.5% 5 year revascularization 95%), the all-cause mortality and remaining secondary endpoints did NOT show significant differences in occurrence at 5 years
When are bare metal stents useful?1) patients for whom bleeding 2) adherence to longer dual anti-platelet therapy (DAPT) therapy or costs are concerns
Chronic polymer-induce inflammation may lead to what?stent restenosis
Why was the permanent metal scaffolding with G4-DES removed?to add back vasoregulation and adoptive vascular responses that were traditionally inhibited by earlier model stents
The EVOLVE and EVOLVE II trials showed what?non-inferiority of Synergy stent compared to a G2-DES at 12 months in terms of death, MI, target lesion revascularization and/or stent thrombosis
The ABSORB trials (of which ABSORB, ABSORB II and ABSORB III have been completed and ABSORB IV is in process) showed what?noninferiority of G4-DES to G2-DES using the same endpoints
What were some concerns regarding the 3 year results of the ABSORB II trial?1)failed to show any significant vasomotor reactivity difference in coronary arteries treated with Absorb stents over G2-DES 2) ABSORB II showed a 2-fold increase in target vessel MI and very late (>12 month) stent thrombosis in the Absorb stent
Dual anti-platelet therapy is recommended for patient who have a cardiac stent, true or false?true
Sept 2016 update (3rd and 4th generation stents were not assessed) made what changes?changes to the duration of dual antiplatelet therapy
List the minimum durations of DAPT (dual antiplatelet therapy) by stent type and indication?1) BMS (bare metal stent) in stable ischemic heart disease should be 1 month and ACS (NSTEM and STEMI) should be 12 months 2) G1-DES in stable ischemic heart disease should be 6 months and in ACS (NSTEMI and STEMI) should be 12 months 3) G2-DES in stable ischemic heart disease should be 6 months and in ACS (NSTEMI and STEMI) should be 12 months
*** Ingeneral, the above numbers listed indicate the _____ duration for dual antiplatelet therapy?minimum
The guidelines delineate longer duration for what patients?1) stable ischemic heart disease 2) patients not at risk of bleeding and with no significant overt bleeding on DAPT
Potentially shorter duration for stable ischemic heart disease treated with drug-eluting stents (>3 months) or all ACS patients (> 6 months) who have what?significant bleeding risks or significant overt bleeding on DAPT
To assist in making decisions on extended DAPT, the ACC/AHA guidelines include a new risk score, called the ____ score? What does it do?1) DAPT score 2) helps balance the net risk/benefit ratio (
*** SUMMARY = Coronary stent technology continues to advance with ______ stents now approved by the FDA?bioresorbable
*** SUMMARY = Enthusiam about the dissolvable stents has been tempered with what reports?of higher rates of complications, including stent thrombosis and MI
*** SUMMARY = True or false? Percutaneous coronary intervention (PCI) with drug-eluting stents is no inferior to coronary artery bypass grafting (CABG) in patients with left main coronary artery disease (LMCAD) and low or intermediate anatomical complexity?true