title: Efficacy of preconditioning with intracoronary diltiazem in preventing laser-induced spasm.
abstract: Laser energy produces a multitude of effects, resulting both in therapeutic tissue ablation and complications such as laser-induced spasm (LIS). LIS can occur during lasing itself or during subsequent adjunctive angioplasty. Intracoronary diltiazem (ICD) can partially reverse LIS after it occurs. To determine whether pre-treatment with ICD might prevent LIS during laser interventions, 3 groups of 50 lesions each were studied. Group 1 served as controls receiving no ICD during the procedure. Group 2 received 2.5 mg ICD before lasing. Group 3 received ICD before lasing and then a second infusion of 2.5 mg ICD after lasing but before adjunctive therapy. There were no differences in clinical characteristics of the 3 groups. Over 75% of lesions in each group were complex (B2 or C) lesions, and average lesion length was 15 mm in all 3 groups. Procedural success was > or = 94% in all groups. There was no significant difference among groups in pre-procedure artery stenosis, post-procedure stenosis, laser power used or number of laser pulses delivered. Pretreatment with ICD produced vasodilation of the minimum lumen diameter from 0.86 +/- 0.1 to 1.0 +/- 0.1 mm (p < 0.01) and was well tolerated. Control patients exhibited a 12% incidence of LIS. Group 2 had an 80% reduction of LIS during lasing (p < 0.01) but had increased LIS during adjunctive therapy with the same 12% incidence of LIS overall. Group 3 had only a 2% incidence of LIS (p < 0.01). We concluded that pretreatment with ICD significantly reduces LIS. Multiple infusions of ICD are necessary to sustain this protective effect.
authors.affiliation: Division of Adult Cardiology, All Childrens Hospital, St. Petersburg, Florida, USA.
authors.forename: M
authors.initials: M
authors.lastname: McIvor
authors.forename: C
authors.initials: C
authors.lastname: Undemir
authors.forename: J
authors.initials: J
authors.lastname: Moses
authors.forename: J
authors.initials: J
authors.lastname: Reddinger
authors.forename: J
authors.initials: J
authors.lastname: Lawson
mesh_terms: D000328:Adult; D000368:Aged; D015906:Angioplasty, Balloon, Coronary / Q000295:instrumentation*; D017222:Angioplasty, Balloon, Laser-Assisted / Q000295:instrumentation*; D002121:Calcium Channel Blockers / Q000008:administration & dosage* / Q000009:adverse effects; D003329:Coronary Vasospasm / Q000000981:diagnostic imaging / Q000517:prevention & control*; D004110:Diltiazem / Q000008:administration & dosage* / Q000009:adverse effects; D004305:Dose-Response Relationship, Drug; D004334:Drug Administration Schedule; D005260:Female; D006801:Humans; D007261:Infusions, Intra-Arterial; D008297:Male; D008875:Middle Aged; D011292:Premedication; D011859:Radiography; D016896:Treatment Outcome