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Six month outcome and determinants of adverse clinical events after successful excimer laser coronary angioplasty
EVOLVING
TECHNOLOGIES
who are at risk of restenosis. Specifically the type of lesions that I believe are high risk are those that are eccentric lesions, those that would have recoil of the normal segment, lesions after balloon angioplasty that have a residual stenosis of >20% or 30%, lesions that have a post-PTCA dissection or lesions in the body of a vein graft that have a very high risk of restenosis. @d.)
least with respect to our current interpretation of the data there is a clear benefit in this subset. Dr. McCallister: I understand that the useof intravascular ultrasound has helped in dealing with subacutethrombosis. Dr. Popma: Absolutely. This is the critical point and representsa turning point with respectto our understanding of how to deploy stentsoptimally. Most of the credit for this is deservedto Antonio Colombo who performed diagnostic intravascular ultrasound in patients who were undergoing stent implantation. He demonstratedthat our current angiographic methods of evaluating the angiogramwere incomplete and that often by intravascular ultrasound the stent struts were not opposed agamstthe vesselwall. The stents were not fully expanded and they were asymmetric. Dr. Colombo performed high pressure balloon inflation and, using intravascular ultrasound made certain that the stent was fully opposed up againstthe vesselwall and fully expanded, and with that he was able to demonstrate a fairly significant reduction in subacutethrombosis.This allowed a reduced anticoagulation regimen. Dr. McCallister: Are you using intravascular ultrasound for all stent deployment? Dr. Popma: We do. I’m not sure that it’s mandatory. We do becausewe learned a tremendousamount about balloon sizing and we’re very comfortable with using intravascular ultrasound to guide whether or not patients receive antithrombotic therapy, either low molecular weight heparin or coumadin after stent deployment versusjust receiving simple antiplatelet therapy, aspirin and ticlopidine. Dr. McCallister: At this point the demonstratedbenefit is only for de novo lesionsor focal lesions.Is that correct? Dr. Popma: Absolutely. Our next task is to expand the lesion subsetsand I think we’ll learn a tremendousamount about the use of stents in acute ischemicsyndromes.We’ll alsolearn whether or not this will have benefit in restenotic lesions.Another critical area that we need to evaluate very closely is the use of stentsm saphenousvein grafts, which comprise a fairly substantial portion of our clinical practice. (Ed.)
ACCEL EXCERPT Stent Placement Rather Than Balloon Angioplasty Should Be the Primary Intervention Employed for Most Patients With Coronary Arterial Stenosis: Affirmative View Jeffrey J. Popma, MD, Washington, DC. Interviewed by Ben D. McCallister, MD. ACCEL Vol. 28, No. 2, February 1996.
Dr. McCallister: Dr. Popma, should we usestentsin the first place for the treatment of patients with coronary stenosisasopposedto plain old balloon angioplasty? Dr. Popma: That question has been the subject of a tremendous amount of researchover the past 2 years and I think that now we have very clear data from two randomized studies that stents provide a benefit with respect to angiographic restenosisas well as pertinent clinical end points such asrevascularization proceduresdue to recurrent ischemia. Thosestudiesare the STRESSI study, which included 410 patients who were randomized to either balloon angioplasty or to stent placement.And in that study the restenosis rate wassignificantly lower in thosepatientswho underwent stent placement(32%) versusthosewho underwent balloon angioplasty (42%). And that occurred in associationwith a significant reduction in target lesion revascularization, 10% in stent-treated patients and 15% in balloon-treated patients. The secondstudy was the BENESTENTstudy, which was a larger study coordinated by Patrick Serruys that demonstrated in 516 patients very similar results, that is, a reduction in angiographic restenosisaswell as the need for clinical revascularization. Dr. McCallister: What about STRESSII? Dr. Popma: STRESSII is a very interestmg study that included an additional 200 patients providing additional clinical power for the initial STRESSI study in that the angiographic restenosisrate was also significantly lower, 30% in stent-treated patients versus45% in balloon-treated patients. Importantly the revascularization rate was 10% in stent-treated patients versus 18% in those treated with balloon angioplasty. Dr. McCallister: Are these results true for all types of lesions? Dr. Popma: These studies were performed in patients with de novo focal stenosesin native coronary vessels.At KC
CURRENT
JOURNAL
LASER ANGIOPLASTY Six Month Outcome and Determinants of Adverse Clinical Events After Successful Excimer Laser Coronary Angioplasty Lloyd W. Klein, Frank Litvack, David Holmes, James Margolis, Donald Rothbaum, Frank Cummins, Neil Eigler, William D’Neill, for the ELCA A.I.S. Multicenter Registry. Rush Heart institute, RusCPresbyteria&t. Luke’s Medical Center, Jelke Pavilion, Chicago, IL J lnvas Cardiol 1995;7:191-9.
Objective:To describethe six month outcome and predictors of adverseclinical events following successfulexcimer laser REVIEW
36
July/August
1996
EVOLVING
TECHNOLOGIES
coronary angioplasty (ELCA). Design: Retrospectiveanalysis of comprehensivedata collected at time of initial procedure and during planned follow-up intervals. Setting:There were 35 participating institutions throughout the United States. Patients: The study population was comprised of 3,069 patientswho had successfulELCA and completed follow-up at 6 months, representing91% of eligible cases.Forty percent had prior balloon angioplasty and 34% had prior bypasssurgery. Measurements:Patient symptomatology was assessedby Canadian Cardiovascular Society functional (CCSF) class.Interim adverseclinical events [death, Q wave myocardial infarction (QMI), repeat intervention, bypass surgery, and a compositeend-point] were tracked. Twentysix pre-ELCA clinical, angiographic and procedural variableswere evaluated to assesstheir ability to predict outcome. Results:At 6 months, there was 2.8% mortality, 2.5% incidence of QMI, and 28.7% required either repeat intervention or bypasssurgery. Overall, 69.2% of patientshad no adverse event. In this cohort, the pre-ELCA CCSF class gradewas2.7 -+ 1.2, but at 6 months, it was0.7 ? 1.1 (p < 0.001). The multivariate predictors of the composite end point were gender, stenosislocation, and rest and unstable angina. Conclusions:There is an excellent 6 month out-
ing a low dependent
Effect of lntracoronary Saline Infusion on Dissection During Excimer Laser Coronary Angioplasty: A Randomized Trial LI. Deckelbaum, M.K. Natarajan, ].A. Bittl, K. Rohlfs, J. Scott, R. Chisholm, K.A. Bowman, B.H. Strauss. Section of Cardiology, West Haven VA Medical Center, Yale University School of Medicine, West Haven, CT, J Am Coll Cardiol I995;26:1264-9.
Objectives:We sought to evaluate whether intracoronary saline infusion during excimer laser coronary angioplasty decreasesthe incidence of significant laser-induced coronary artery dissections.Background:Despiteprocedural successrates >90%, coronary artery dissectionsoccur in 17% to 27% of excimer laser coronary angioplasty procedures. Excimer laser irradiation of blood results in vapor bubble formation and acoustomechanicaltrauma to the vesselwall. Salineinfusion into a coronary artery may minimize blood irradiation and consequentarterial wall damage.Methods:In this prospective, randomized, controlled study, consecutive patients undergoing excimer laser coronary angioplasty were randomly assignedto conventional laserirradiation in a blood medium or to laserirradiation with blood displacement by intracoronary salineinfusion. In the patients randomized to intracoronary salineinfusion, prewarmed normal saline was injected through the coronary artery guide catheter at a rate of 1 to 2 ml/s using a power injector. The incidence and severity of dissectionafter excimer laserablation were evaluated in a core laboratory by angiographers with no knowledge of treatment assignment.The severity of coronary artery dissectionwas rated on an ordinal scaleof 1 to 5. Dissections of grade 2 or higher were considered significant. Results:The mean (+ SE) dissectiongrade after laser angioplasty in patients treated with intracoronary saline infusionwas 0.43 2 0.13 comparedwith 0.91 t 0.26 in patients undergoing laser angioplasty in a blood medium. The incidence of significant dissection was 7% in salinetreated patients compared with 24% in conventionally treated patients (p < 0.05). No significant complications were associatedwith saline infusion. Conclusions: Intra-
come after successful ELCA in this selected population with complex coronary artery disease. The majority of patients without interim events enjoy significant alleviation of symptoms. The predictors of adverse events are clinical rather than angiographic.
Predictors of Restenosis After Excimer Laser Coronary Angioplasty Z.M.B. Ghazzal, E. Burton, W.S. Weintraub, F. Litvack, D.A. Rothbaum, L Klein, S.B. King Ill. Emory University Hospital, Atlanta, GA. Am J Cardiol 1995;75:1012-4.
One hundred twenty-five lesionssuccessfullytreated with excimer laser coronary angioplasty at 3 centers were analyzed in a central core laboratory using detailed quantitative angiographic analysis.Sixty-seven narrowings had restenosis(250% diameterstenosisat restudy). Correlatesof restenosiswere asfollows: baselinediameterstenosiswas 79% in the restenosisgroup versus 71% in the group without restenosis(p = 0.0002), baselineminimal diameterstenosiswas 0.55 mm in the restenosisgroup versus 0.72 mm in the group without restenosis(p = 0.006), final diameter stenosiswas40% in the restenosisgroup versus32% in the group without restenosis(p = 0.002), lesion length 27 mm was present in 43% of the restenosisgroup versus 21% in the group without restenosis(p = 0.009), and Thrombolysis in Myocardial Infarction trial flow 0 to 2 was 33% in the restenosisgroup versus15% in the group without restenosis (p = 0.025). The strongest multivariate correlate of restenosis was the baseline Whereas most predictors
coronary saline infusion should be incorporated excimer laser coronary angioplasty procedures.
CURRENT
JOURNAL
into all
Randomised Trial of Excimer laser Angioplasty Versus Balloon Angioplasty for Treatment of Obstructive Coronary Artery Disease Y.E.A. Appelman, J.J. Pick, S. Strikwerda, J.G.P. Tijssen, P.J. De Feyter, G.K. David, P.W. Sermys, J.R. Margolis, Il.]. Koelemay, E.W.J. Montauban van Swijndregt J.J. Koolen. University of Amsterdam, Department of Cardiology, Academic Medical Centre, Amsterdam, The Netherlands. lancet 1996;347:79-84.
Background:Excimer laser coronary angioplasty is reported to give excellent procedural resultsfor treatment of complex
diameter stenosis (p = 0.003). were not controllable, achievKC
residual diameter stenosis that is operatorcan favorably influence the restenosis rate.
REVIEW
37
July/.4u~usl
1996
TECHNOLOGIES
who are at risk of restenosis. Specifically the type of lesions that I believe are high risk are those that are eccentric lesions, those that would have recoil of the normal segment, lesions after balloon angioplasty that have a residual stenosis of >20% or 30%, lesions that have a post-PTCA dissection or lesions in the body of a vein graft that have a very high risk of restenosis. @d.)
least with respect to our current interpretation of the data there is a clear benefit in this subset. Dr. McCallister: I understand that the useof intravascular ultrasound has helped in dealing with subacutethrombosis. Dr. Popma: Absolutely. This is the critical point and representsa turning point with respectto our understanding of how to deploy stentsoptimally. Most of the credit for this is deservedto Antonio Colombo who performed diagnostic intravascular ultrasound in patients who were undergoing stent implantation. He demonstratedthat our current angiographic methods of evaluating the angiogramwere incomplete and that often by intravascular ultrasound the stent struts were not opposed agamstthe vesselwall. The stents were not fully expanded and they were asymmetric. Dr. Colombo performed high pressure balloon inflation and, using intravascular ultrasound made certain that the stent was fully opposed up againstthe vesselwall and fully expanded, and with that he was able to demonstrate a fairly significant reduction in subacutethrombosis.This allowed a reduced anticoagulation regimen. Dr. McCallister: Are you using intravascular ultrasound for all stent deployment? Dr. Popma: We do. I’m not sure that it’s mandatory. We do becausewe learned a tremendousamount about balloon sizing and we’re very comfortable with using intravascular ultrasound to guide whether or not patients receive antithrombotic therapy, either low molecular weight heparin or coumadin after stent deployment versusjust receiving simple antiplatelet therapy, aspirin and ticlopidine. Dr. McCallister: At this point the demonstratedbenefit is only for de novo lesionsor focal lesions.Is that correct? Dr. Popma: Absolutely. Our next task is to expand the lesion subsetsand I think we’ll learn a tremendousamount about the use of stents in acute ischemicsyndromes.We’ll alsolearn whether or not this will have benefit in restenotic lesions.Another critical area that we need to evaluate very closely is the use of stentsm saphenousvein grafts, which comprise a fairly substantial portion of our clinical practice. (Ed.)
ACCEL EXCERPT Stent Placement Rather Than Balloon Angioplasty Should Be the Primary Intervention Employed for Most Patients With Coronary Arterial Stenosis: Affirmative View Jeffrey J. Popma, MD, Washington, DC. Interviewed by Ben D. McCallister, MD. ACCEL Vol. 28, No. 2, February 1996.
Dr. McCallister: Dr. Popma, should we usestentsin the first place for the treatment of patients with coronary stenosisasopposedto plain old balloon angioplasty? Dr. Popma: That question has been the subject of a tremendous amount of researchover the past 2 years and I think that now we have very clear data from two randomized studies that stents provide a benefit with respect to angiographic restenosisas well as pertinent clinical end points such asrevascularization proceduresdue to recurrent ischemia. Thosestudiesare the STRESSI study, which included 410 patients who were randomized to either balloon angioplasty or to stent placement.And in that study the restenosis rate wassignificantly lower in thosepatientswho underwent stent placement(32%) versusthosewho underwent balloon angioplasty (42%). And that occurred in associationwith a significant reduction in target lesion revascularization, 10% in stent-treated patients and 15% in balloon-treated patients. The secondstudy was the BENESTENTstudy, which was a larger study coordinated by Patrick Serruys that demonstrated in 516 patients very similar results, that is, a reduction in angiographic restenosisaswell as the need for clinical revascularization. Dr. McCallister: What about STRESSII? Dr. Popma: STRESSII is a very interestmg study that included an additional 200 patients providing additional clinical power for the initial STRESSI study in that the angiographic restenosisrate was also significantly lower, 30% in stent-treated patients versus45% in balloon-treated patients. Importantly the revascularization rate was 10% in stent-treated patients versus 18% in those treated with balloon angioplasty. Dr. McCallister: Are these results true for all types of lesions? Dr. Popma: These studies were performed in patients with de novo focal stenosesin native coronary vessels.At KC
CURRENT
JOURNAL
LASER ANGIOPLASTY Six Month Outcome and Determinants of Adverse Clinical Events After Successful Excimer Laser Coronary Angioplasty Lloyd W. Klein, Frank Litvack, David Holmes, James Margolis, Donald Rothbaum, Frank Cummins, Neil Eigler, William D’Neill, for the ELCA A.I.S. Multicenter Registry. Rush Heart institute, RusCPresbyteria&t. Luke’s Medical Center, Jelke Pavilion, Chicago, IL J lnvas Cardiol 1995;7:191-9.
Objective:To describethe six month outcome and predictors of adverseclinical events following successfulexcimer laser REVIEW
36
July/August
1996
EVOLVING
TECHNOLOGIES
coronary angioplasty (ELCA). Design: Retrospectiveanalysis of comprehensivedata collected at time of initial procedure and during planned follow-up intervals. Setting:There were 35 participating institutions throughout the United States. Patients: The study population was comprised of 3,069 patientswho had successfulELCA and completed follow-up at 6 months, representing91% of eligible cases.Forty percent had prior balloon angioplasty and 34% had prior bypasssurgery. Measurements:Patient symptomatology was assessedby Canadian Cardiovascular Society functional (CCSF) class.Interim adverseclinical events [death, Q wave myocardial infarction (QMI), repeat intervention, bypass surgery, and a compositeend-point] were tracked. Twentysix pre-ELCA clinical, angiographic and procedural variableswere evaluated to assesstheir ability to predict outcome. Results:At 6 months, there was 2.8% mortality, 2.5% incidence of QMI, and 28.7% required either repeat intervention or bypasssurgery. Overall, 69.2% of patientshad no adverse event. In this cohort, the pre-ELCA CCSF class gradewas2.7 -+ 1.2, but at 6 months, it was0.7 ? 1.1 (p < 0.001). The multivariate predictors of the composite end point were gender, stenosislocation, and rest and unstable angina. Conclusions:There is an excellent 6 month out-
ing a low dependent
Effect of lntracoronary Saline Infusion on Dissection During Excimer Laser Coronary Angioplasty: A Randomized Trial LI. Deckelbaum, M.K. Natarajan, ].A. Bittl, K. Rohlfs, J. Scott, R. Chisholm, K.A. Bowman, B.H. Strauss. Section of Cardiology, West Haven VA Medical Center, Yale University School of Medicine, West Haven, CT, J Am Coll Cardiol I995;26:1264-9.
Objectives:We sought to evaluate whether intracoronary saline infusion during excimer laser coronary angioplasty decreasesthe incidence of significant laser-induced coronary artery dissections.Background:Despiteprocedural successrates >90%, coronary artery dissectionsoccur in 17% to 27% of excimer laser coronary angioplasty procedures. Excimer laser irradiation of blood results in vapor bubble formation and acoustomechanicaltrauma to the vesselwall. Salineinfusion into a coronary artery may minimize blood irradiation and consequentarterial wall damage.Methods:In this prospective, randomized, controlled study, consecutive patients undergoing excimer laser coronary angioplasty were randomly assignedto conventional laserirradiation in a blood medium or to laserirradiation with blood displacement by intracoronary salineinfusion. In the patients randomized to intracoronary salineinfusion, prewarmed normal saline was injected through the coronary artery guide catheter at a rate of 1 to 2 ml/s using a power injector. The incidence and severity of dissectionafter excimer laserablation were evaluated in a core laboratory by angiographers with no knowledge of treatment assignment.The severity of coronary artery dissectionwas rated on an ordinal scaleof 1 to 5. Dissections of grade 2 or higher were considered significant. Results:The mean (+ SE) dissectiongrade after laser angioplasty in patients treated with intracoronary saline infusionwas 0.43 2 0.13 comparedwith 0.91 t 0.26 in patients undergoing laser angioplasty in a blood medium. The incidence of significant dissection was 7% in salinetreated patients compared with 24% in conventionally treated patients (p < 0.05). No significant complications were associatedwith saline infusion. Conclusions: Intra-
come after successful ELCA in this selected population with complex coronary artery disease. The majority of patients without interim events enjoy significant alleviation of symptoms. The predictors of adverse events are clinical rather than angiographic.
Predictors of Restenosis After Excimer Laser Coronary Angioplasty Z.M.B. Ghazzal, E. Burton, W.S. Weintraub, F. Litvack, D.A. Rothbaum, L Klein, S.B. King Ill. Emory University Hospital, Atlanta, GA. Am J Cardiol 1995;75:1012-4.
One hundred twenty-five lesionssuccessfullytreated with excimer laser coronary angioplasty at 3 centers were analyzed in a central core laboratory using detailed quantitative angiographic analysis.Sixty-seven narrowings had restenosis(250% diameterstenosisat restudy). Correlatesof restenosiswere asfollows: baselinediameterstenosiswas 79% in the restenosisgroup versus 71% in the group without restenosis(p = 0.0002), baselineminimal diameterstenosiswas 0.55 mm in the restenosisgroup versus 0.72 mm in the group without restenosis(p = 0.006), final diameter stenosiswas40% in the restenosisgroup versus32% in the group without restenosis(p = 0.002), lesion length 27 mm was present in 43% of the restenosisgroup versus 21% in the group without restenosis(p = 0.009), and Thrombolysis in Myocardial Infarction trial flow 0 to 2 was 33% in the restenosisgroup versus15% in the group without restenosis (p = 0.025). The strongest multivariate correlate of restenosis was the baseline Whereas most predictors
coronary saline infusion should be incorporated excimer laser coronary angioplasty procedures.
CURRENT
JOURNAL
into all
Randomised Trial of Excimer laser Angioplasty Versus Balloon Angioplasty for Treatment of Obstructive Coronary Artery Disease Y.E.A. Appelman, J.J. Pick, S. Strikwerda, J.G.P. Tijssen, P.J. De Feyter, G.K. David, P.W. Sermys, J.R. Margolis, Il.]. Koelemay, E.W.J. Montauban van Swijndregt J.J. Koolen. University of Amsterdam, Department of Cardiology, Academic Medical Centre, Amsterdam, The Netherlands. lancet 1996;347:79-84.
Background:Excimer laser coronary angioplasty is reported to give excellent procedural resultsfor treatment of complex
diameter stenosis (p = 0.003). were not controllable, achievKC
residual diameter stenosis that is operatorcan favorably influence the restenosis rate.
REVIEW
37
July/.4u~usl
1996