- Email: [email protected]
Laser angioplasty of restenosed coronary stents: Results of a multicenter surveillance trial
LITERATURE REVIEW
mortality is high, future studies are needed to compare this technique directly with surgery.
Kastrati A, Elezi S, Dirschinger J, et al: Influence of lesion length on restenosis after coronary stent placement. Am J Cardiol 83:1617-1622, 1999 Because of the complexity of long coronary lesions, it is unclear if stenting provides advantages over angioplasty in patients with long lesions. From 1994 to 1997, patients who underwent stent placement were studied. Data were obtained on stent type, stent number, lesion length, ventricular function, lumen size, and short-term and long-term (6 months) follow-up. All lesions greater than 15 m m in length were considered long lesions. Procedural success was similar for long and short lesions; however, event-free 1-year survival was 73% for long lesions and 80% for short lesions (p = 0.001). Restenosis rate was higher, late lumen loss was greater, and repeat angioplasty was more frequent in patients with long lesions. Independent multivariate predictors of restenosis were lesion length, number of stents, and stent overlap. Implication: To reduce the morbidity associated with stenting long coronary lesions, stent overlap should potentially be avoided.
Koster R, Hamm CW, Seabra-Gomes R, et al: Laser angioplasty of restenosed coronary stents: Results of a multicenter surveillance trial. J Am Coil Cardiol 34:25-32, 1999 This was a multicenter surveillance trial to evaluate the use of excimer laser with adjunctive angioplasty to treat in-stent restenosis of greater than 70% of luminal diameter. Treatment of native and saphenous vein graft stents was included (n = 527 stents). Laser angioplasty success was defined as less than 50% residual stenosis, and procedural success was defined as less than 30% residual stenosis or successful pass of a specific catheter. Laser angioplasty was feasible in 98% of attempts. There were no differences in success rates with regard to lesion length, artery size, artery involvement, or native or vein graft involvement. Implication: The recurrence rate for dilated restenotic stents is higher than for nonstented lesions. Ablation of plaque mass using laser technology may be a potential therapeutic advantage.
Thebault J-J, Kieffer G, Cariou R: Single-dose pharmacodynamics of clopidogrel. Semin Thromb Hemost 25:3-8, 1999 In a randomized, double-blind, placebo-controlled, rising-dose study in healthy men, clopidogrel in doses of 0 rag, 100 mg, 200 mg, 400 mg, and 600 mg was given during five study periods and a washout period of at least 7 days. Platelet aggregation to adenosine diphosphate (ADP) and bleeding time were compared. Clopidogrel caused a dose-related decrease in platelet aggregation to 5 gM ADP up to 400 mg. There was no further increase at 600 mg. There was also a slight but less pronounced depression of collagen-induced platelet aggregation. Bleeding time was prolonged only after the 600-rag dose. There were no adverse effects of larger doses of drug. Implication: The use of a single large close of clopidogrel may allow steady-state plasma levels that provide maximal platelet inhibition to be achieved earlier than if multiple small daily doses are used.
Caplain H, Cariou R: Long-term activity of clopidogrel: A three-month appraisal in healthy volunteers. Semin Thromb Hemost 25:21-23, 1999 In 35 healthy subjects, adenosine diphosphate-induced platelet aggregation and bleeding time were measured at regular intervals
101
during a 12-week study. After baseline samples were obtained, clopidogrel was ingested in a daily dose of 75 mg for 12 weeks. Percent inhibition of aggregation at steady state was 42.9% _+ 11.6% and 39% _+ 17% at the end of week 12. Two weeks after drug cessation (week 14), aggregation returned to baseline values. Bleeding time was prolonged at steady state by a factor of 2.15 and returned to baseline within 2 weeks of discontinuing drug therapy. Implication: Inhibition of platelet aggregation by clopidogrel can be maintained at steady state using 75 rag~day dosing and returned to baseline within 2 weeks of stopping treatment. EPIDEMIOLOGY
Vaturi M, Porter A, Adler Y, et al: The natural history of aortic valve disease after mitral valve surgery. J Am Coll Cardio133:2003-2008, 1999 In patients presenting for rheumatic mitral valve surgery, little is known about the natural history of the aortic valve. In a retrospective case review, 59 of 131 patients had some form of aortic valve disease at the time of mitral valve surgery. Most patients had mild aortic regurgitation, whereas the rest had mild aortic stenosis with or without aortic regurgitation. During a follow-up of 13 -- 7 years, 36 additional patients acquired aortic valve disease, most having mild aortic disease. Ninety percent of patients who initially had mild aortic regurgitation had little progression of valvular disease. Only six patients (5%) in the entire cohort required aortic valve replacement; 4 of these 6 presented primarily for recurrent mitral valve disease. Implication: A significant number of patients presenting for rheumatic mitral valve operations have some aortic valve disease. This disease usually does not progress to require surgical intervention.
Christenson JT, Dimonet F, Schmuziger M: The influence of age on the outcome of primary coronary artery bypass grafting. J Cardiovasc Surg 40:333-338, 1999 This retrospective review was undertaken in 2,127 patients undergoing coronary artery bypass graft (CABG) surgery to assess morbidity and mortality in certain age groups and to define the justification for performing CABG surgery in the elderly. Patients were divided into four age groups: less than 70 years, 70 to 75 years, 76 to 80 years, and older than 80 years. There were no statistical differences among groups with respect to mortality, pulmonary complications, or neurologic complications except for a higher incidence of gastrointestinal complications and low cardiac output in patients older than 70 years. Patients younger than 70 years had a significantly shorter intensive care unit stay (p < 0.001), but no differences were noted among the patient groups older than 70 years. There were no differences in 5-year survival in patients 70 to 80 years of age when compared with their age-matched population controls. Implication: CABG surgery in elderly patients has a slightly higher morbidity. The acceptable mortality and event-free survival rates justify the use of CABG surgery in patients older than 70 years. ACKNO WLEDG MENT
Papers reviewed in this issue were selected from those published in the following journals: American Journal of Cardiology, Catheterization and Cardiovascular Interventions, Journal of the American College of Cardiology, Journal of Cardiovascular Surge~ Journal of Vascular Surgery, Seminars in Thrombosis and Hemostasis, and Thoracic Cardiovascular Surgery. Contributions to the Literature Reviews were made by David Moskowitz, MD, Mount Sinai Hospital, New York, NY.
mortality is high, future studies are needed to compare this technique directly with surgery.
Kastrati A, Elezi S, Dirschinger J, et al: Influence of lesion length on restenosis after coronary stent placement. Am J Cardiol 83:1617-1622, 1999 Because of the complexity of long coronary lesions, it is unclear if stenting provides advantages over angioplasty in patients with long lesions. From 1994 to 1997, patients who underwent stent placement were studied. Data were obtained on stent type, stent number, lesion length, ventricular function, lumen size, and short-term and long-term (6 months) follow-up. All lesions greater than 15 m m in length were considered long lesions. Procedural success was similar for long and short lesions; however, event-free 1-year survival was 73% for long lesions and 80% for short lesions (p = 0.001). Restenosis rate was higher, late lumen loss was greater, and repeat angioplasty was more frequent in patients with long lesions. Independent multivariate predictors of restenosis were lesion length, number of stents, and stent overlap. Implication: To reduce the morbidity associated with stenting long coronary lesions, stent overlap should potentially be avoided.
Koster R, Hamm CW, Seabra-Gomes R, et al: Laser angioplasty of restenosed coronary stents: Results of a multicenter surveillance trial. J Am Coil Cardiol 34:25-32, 1999 This was a multicenter surveillance trial to evaluate the use of excimer laser with adjunctive angioplasty to treat in-stent restenosis of greater than 70% of luminal diameter. Treatment of native and saphenous vein graft stents was included (n = 527 stents). Laser angioplasty success was defined as less than 50% residual stenosis, and procedural success was defined as less than 30% residual stenosis or successful pass of a specific catheter. Laser angioplasty was feasible in 98% of attempts. There were no differences in success rates with regard to lesion length, artery size, artery involvement, or native or vein graft involvement. Implication: The recurrence rate for dilated restenotic stents is higher than for nonstented lesions. Ablation of plaque mass using laser technology may be a potential therapeutic advantage.
Thebault J-J, Kieffer G, Cariou R: Single-dose pharmacodynamics of clopidogrel. Semin Thromb Hemost 25:3-8, 1999 In a randomized, double-blind, placebo-controlled, rising-dose study in healthy men, clopidogrel in doses of 0 rag, 100 mg, 200 mg, 400 mg, and 600 mg was given during five study periods and a washout period of at least 7 days. Platelet aggregation to adenosine diphosphate (ADP) and bleeding time were compared. Clopidogrel caused a dose-related decrease in platelet aggregation to 5 gM ADP up to 400 mg. There was no further increase at 600 mg. There was also a slight but less pronounced depression of collagen-induced platelet aggregation. Bleeding time was prolonged only after the 600-rag dose. There were no adverse effects of larger doses of drug. Implication: The use of a single large close of clopidogrel may allow steady-state plasma levels that provide maximal platelet inhibition to be achieved earlier than if multiple small daily doses are used.
Caplain H, Cariou R: Long-term activity of clopidogrel: A three-month appraisal in healthy volunteers. Semin Thromb Hemost 25:21-23, 1999 In 35 healthy subjects, adenosine diphosphate-induced platelet aggregation and bleeding time were measured at regular intervals
101
during a 12-week study. After baseline samples were obtained, clopidogrel was ingested in a daily dose of 75 mg for 12 weeks. Percent inhibition of aggregation at steady state was 42.9% _+ 11.6% and 39% _+ 17% at the end of week 12. Two weeks after drug cessation (week 14), aggregation returned to baseline values. Bleeding time was prolonged at steady state by a factor of 2.15 and returned to baseline within 2 weeks of discontinuing drug therapy. Implication: Inhibition of platelet aggregation by clopidogrel can be maintained at steady state using 75 rag~day dosing and returned to baseline within 2 weeks of stopping treatment. EPIDEMIOLOGY
Vaturi M, Porter A, Adler Y, et al: The natural history of aortic valve disease after mitral valve surgery. J Am Coll Cardio133:2003-2008, 1999 In patients presenting for rheumatic mitral valve surgery, little is known about the natural history of the aortic valve. In a retrospective case review, 59 of 131 patients had some form of aortic valve disease at the time of mitral valve surgery. Most patients had mild aortic regurgitation, whereas the rest had mild aortic stenosis with or without aortic regurgitation. During a follow-up of 13 -- 7 years, 36 additional patients acquired aortic valve disease, most having mild aortic disease. Ninety percent of patients who initially had mild aortic regurgitation had little progression of valvular disease. Only six patients (5%) in the entire cohort required aortic valve replacement; 4 of these 6 presented primarily for recurrent mitral valve disease. Implication: A significant number of patients presenting for rheumatic mitral valve operations have some aortic valve disease. This disease usually does not progress to require surgical intervention.
Christenson JT, Dimonet F, Schmuziger M: The influence of age on the outcome of primary coronary artery bypass grafting. J Cardiovasc Surg 40:333-338, 1999 This retrospective review was undertaken in 2,127 patients undergoing coronary artery bypass graft (CABG) surgery to assess morbidity and mortality in certain age groups and to define the justification for performing CABG surgery in the elderly. Patients were divided into four age groups: less than 70 years, 70 to 75 years, 76 to 80 years, and older than 80 years. There were no statistical differences among groups with respect to mortality, pulmonary complications, or neurologic complications except for a higher incidence of gastrointestinal complications and low cardiac output in patients older than 70 years. Patients younger than 70 years had a significantly shorter intensive care unit stay (p < 0.001), but no differences were noted among the patient groups older than 70 years. There were no differences in 5-year survival in patients 70 to 80 years of age when compared with their age-matched population controls. Implication: CABG surgery in elderly patients has a slightly higher morbidity. The acceptable mortality and event-free survival rates justify the use of CABG surgery in patients older than 70 years. ACKNO WLEDG MENT
Papers reviewed in this issue were selected from those published in the following journals: American Journal of Cardiology, Catheterization and Cardiovascular Interventions, Journal of the American College of Cardiology, Journal of Cardiovascular Surge~ Journal of Vascular Surgery, Seminars in Thrombosis and Hemostasis, and Thoracic Cardiovascular Surgery. Contributions to the Literature Reviews were made by David Moskowitz, MD, Mount Sinai Hospital, New York, NY.