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Measuring the Switch Cost of Smartphone Use While Walking
Published on: April 30, 2020
Intentional switch between 1.5-mm and 1.25-mm burrs along with switch between rotawire floppy and extra-support for
Yousuke Taniguchi1, Kenichi Sakakura1, Yasuhiro Mukai1
1Division of Cardiovascular Medicine, Saitama Medical Center, Jichi Medical University, Saitama, Japan.
Abstract:
Rotational atherectomy (RA) is considered to be the last resort for a severely calcified coronary artery lesion. Severe complications such as vessel perforation or burr entrapment is closely associated with forceful burr manipulation during RA. The instructions for use of Rotablator (Boston Scientific, Marlborough, MA, USA) prohibit forceful burr manipulation when rotational resistance occurs. Nevertheless, RA operators tend to forcefully manipulate the burr if it cannot cross the lesion, because there has been no established strategy for an uncrossable lesion. We present a case with a severely calcified coronary lesion, which was uncrossable by a burr 1.5 mm with RotaWire Floppy (Boston Scientific). We intentionally switched 2 burrs (1.5-mm and 1.25-mm) and 2 RotaWires (Floppy and Extra-support) to cross the lesion. Uniquely, we downsized the burr (from 1.5-mm to 1.25-mm) initially for better penetration force, and upsized the burr (from 1.25-mm to 1.5-mm) finally for better contact to the calcification within the lesion. Our case suggests that 4 different types of combinations might work in a mutually complementary manner for an uncrossable calcified lesion. <Learning Objective: In rotational atherectomy, severe complications such as vessel perforation or burr entrapment are closely associated with forceful burr manipulation. We present a case with a severely calcified coronary lesion, which was uncrossable by a burr 1.5 mm with RotaWire Floppy. We intentionally switched 2 burrs and 2 RotaWires to cross the lesion. Our case suggests that 4 different types of combinations might work in a mutually complementary manner for an uncrossable calcified lesion.>.
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