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Make your selection before scrolling down beyond this point Answer: Angiography has poor sensitivity
for detecting mild-to-moderate lesion calcium, and only moderate sensitivity for extensive
lesion calcium. (Answer: b (false) Make your selection before scrolling down beyond this point Answer: In one report, 11% of lesions with
angiographic calcium failed to show calcium by IVUS (i.e., false positives).
(Answer: a (true) Make your selection before scrolling down beyond this point Answer: IVUS has shown that lesion calcium
plays a direct role in promoting dissection following PTCA. In a report involving 41
patients undergoing coronary and peripheral angioplasty, both the incidence (88% vs. 53%
for non-calcified lesions) and extent of dissection were significantly higher among
calcified lesions. When present, the dissection usually originated at the transition
between calcified and noncalcified plaque, presumably due to nonuniform shear forces
generated by balloon expansion. (Answer: a (true) Make your selection before scrolling down beyond this point Answer: Most reports have failed to show any association between lesion calcium and restenosis after PTCA. (Answer: b (false) 5. Acceptable interventional
techniques for undilatable calcified lesions include: Make your selection before scrolling down beyond this point Answer: Rotablator is the treatment of choice for undilatable lesions; other potentially useful techniques include force-focused angioplasty and ELCA. (Answer: a, c, d) 6. The device of choice for the
treatment of calcified lesions is: Make your selection before scrolling down beyond this point Answer: High procedural success (> 90%)
and low complication rates (< 5%) can be achieved after Rotablator atherectomy of
calcified stenoses. In fact, Ellis et al found that lesions without calcium were at
greater risk for procedural complications compared to lesions with calcium. Rotablator
atherectomy preferentially ablates calcified atheroma; results in a larger and more
concentric lumen with fewer dissections in calcified vs. noncalcified lesions; and
produces microfractures in calcified deposits, increasing lesion compliance and rendering
them more susceptible to PTCA. Among 67 undilatable lesions treated with the Rotablator
(73% of which were calcified), overall procedural success was 96%. After atherectomy, 78%
of previously undilatable lesions responded to inflation pressures < 6 atm. In an IVUS
study of Rotablator followed by PTCA, DCA, or stents, Rotablator + stent achieved the
largest lumen and smallest residual stenosis (Rota + PTCA = 24%; Rota + DCA = 16%; Rota +
stent = 12%, p < 0.0001). At the present time, Rotablator atherectomy is the preferred
method of revascularizing moderate-to-heavily calcified stenoses. (Answer: c) Make your selection before scrolling down beyond this point Answer: Directional Coronary Atherectomy
(DCA) has a very limited ability to excise calcified plaque and should be avoided when
moderate-to-heavy lesion calcium is present. IVUS studies clearly show that the presence
and extent of lesion calcium correlates with ineffective plaque removal after primary
DCA. Future development of calcium-cutters may improve DCA success. TEC has an
extremely limited ability to cut calcium and should not be used on heavily calcified
lesions. Because of the excellent flexibility of TEC cutters, vessel calcification
proximal to the target lesion is not a contraindication to TEC atherectomy. (Answer:
b (false) Make your selection before scrolling down beyond this point Answer: Heavy lesion calcium increases the
risk of incomplete stent expansion and restenosis; a stent should not be deployed in a
calcified lesion if full balloon expansion cannot be achieved, since incomplete stent
expansion greatly increases the risk of stent thrombosis. Even when heavily
calcified plaque is first modified by the Rotablator, final lumen cross-sectional area
after stenting may be smaller than in lesions without calcification, but is still larger
than the combination of Rotablator plus PTCA or DCA. Final diameter stenosis and target
lesion revascularization appear to be lowest after Rotablator plus stenting compared to
stenting alone or Rotablator plus DCA or PTCA. (Answer: b (false) Make your selection before scrolling down beyond this point Answer: ELCA is an alternative to Rotablator for superficial lesion calcification; small initial fibers (1.3 mm), high fluence (50-60 mJ/mm2), and the saline-infusion technique are recommended. (Answer: b) 10. Techniques to minimize
no-reflow after Rotablator atherectomy of calcified lesions include: Make your selection before scrolling down beyond this point Answer: The mechanism of Rotablator atherectomy is tissue displacement by pulvuarization and microembolization. No-reflow is uncommon, and can be virtually eliminated by using a small initial burr, stepwire increments in burr size, ablation runs < 30 sec, careful attention to burr speed with RPM surveillance, and a Rotaflush cocktail of nitrates, calcium blockers, and heparin. (Answer: a, d, e) 11. All of the following statements
about lesions with deep calcium (i.e., at or near the medial-adventitial border) are true
except: Make your selection before scrolling down beyond this point Answer: Unlike calcium located at the intimal-lumen interface, deep tissue calcium (at or near the medial-adventitial border) does not usually interfere with PTCA, DCA, or stenting. Initial use of Rotablator or ELCA is not generally required, and device selection can be based on associated lesion morphologies. Deep calcium has little or no impact on procedural outcome. (Answer: c)
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