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Transmyocardial CO2 laser revascularization improves symptoms, function, and quality of life: 12-month results from a randomized controlled trial
high-risk CABG). A total of 2918 patients were assigned to the entry category of CABG. Patients were considered as high risk for CABG if they required an urgent intervention (such as after failed PTCA) or repeat CABG or if they had a history of angina at rest or at minimal exercise within the past 4 weeks and with the presence of two or more of the following: age ⬎65 years, female gender, diabetes mellitus, left ventricular ejection fraction ⬍35% and left main or three-vessel disease. Serial creatine kinase-myocardial band (CK-MB) isoenzyme measurements were obtained at baseline and at 8, 12, 16 and 24 hours after CABG. Results: The unadjusted 6-month mortality rates were 3.4%, 5.8%, 7.8% and 20.2% for patients with a postoperative peak CK-MB ratio (peak CK-MB value/upper limits of normal [ULN] for laboratory test) of ⬍5, ⬎5 to ⬍10, ⬎10 to ⬍20 and ⬎20 ULN, respectively (p⬍0.0001). This trend for increasing risk remained statistically significant after adjustment for ejection fraction, congestive heart failure, cerebrovascular disease, peripheral vascular disease, cardiac arrhythmias and the method of cardioplegia delivery (area under the receiver operative curve⫽0.648, p⬍0.001); the optimal cut-point to predict 6-month mortality ranged from 5 to 10 ULN. Conclusion: Progressive elevation of the CK-MB ratio in clinically high-risk patients is associated with significant elevations of medium-term mortality after CABG. Strategies to afford myocardial protection both during CABG and in the postoperative phase may serve to improve the clinical outcome. Perspective: The current study highlights the need for optimal myocardial protection technique for reducing the degree of myocardial necrosis during CABG. Routine biomarker surveillance after CABG in high-risk patients to identify evidence of myocardial necrosis may help identify those at high risk for adverse events and who would potentially benefit from therapies such as beta-blockers to improve long-term outcomes. RM
Methods: In the Bypass Angioplasty Revascularization Investigation (BARI), 1829 patients with multivessel disease were randomized to an initial strategy of PTCA or CABG between 1988 and 1991. Stents and IIb/IIIa inhibitors were not utilized. Subsets of high-risk patients were evaluated to ascertain if the two reperfusions strategy conferred differential survival benefit. Results: Seven-year survival among patients with threevessel disease undergoing PTCA and CABG (n⫽754) was 79% vs. 84% (p⫽0.06), respectively, and 85% vs. 87% (p⫽0.36) when only non-diabetics (n⫽592) were analyzed. In patients with three-vessel disease and reduced LV function (ejection fraction ⬍50%), 7-year survival was similar in all PTCA and CABG patients (n⫽ 176, 70% vs. 74%; p⫽0.6) as well as among non-diabetics (n⫽124, 82% vs. 73%; p⫽0.29). Seven-year survival was also similar in all PTCA and CABG patients with two-vessel disease involving proximal LAD (n⫽352, 87% vs. 84%; p⫽0.9) and in nondiabetics with two-vessel disease involving proximal LAD and preserved LV function (n⫽287, 93% vs. 87%, p⫽0.27). In patients with two-vessel disease and reduced LV function, 7-year survival was also similar in all PTCA and CABG patients (n⫽72, 78% vs. 71%, p⫽0.7) as well as among non-diabetics (n⫽46, 90% vs. 67%, p⫽0.13). Conclusion: Revascularization by PTCA and CABG yielded equivalent survival over 7 years among high-risk anatomic subsets in which survival is prolonged by CABG vs. medical therapy. Perspective: These results suggesting similar 7-year survival with PTCA and CABG in high-risk patients should be viewed in light of the fact that only 12% of patients evaluated for BARI were randomized, most have preserved LV function and almost all had lesions that were amenable to either revascularization strategy. In addition, subgroup sample sizes at 7 years are sufficiently small to limit ability to detect modest survival differences. RM
Survival Following Coronary Angioplasty vs. Coronary Artery Bypass Surgery in Anatomic Subsets in Which Coronary Artery Bypass Surgery Improves Survival Compared With Medical Therapy. Results From the Bypass Angioplasty Revascularization Investigation (BARI)
Transmyocardial CO2 Laser Revascularization Improves Symptoms, Function, and Quality of Life: 12-Month Results From a Randomized Controlled Trial Spertus JA, Jones PG, Coen M, et al. Am J Med 2001;111:341– 8. Study Question: Are there differences in health status (symptoms, physical function and quality of life) between continued medical management and transmyocardial revascularization with a carbon dioxide laser in patients with severe, symptomatic, inoperable coronary artery disease? Methods: This prospective, multicenter trial randomized 98 patients to transmyocardial revascularization and 99 to continued medical therapy. Health status was assessed with the Seattle Angina Questionnaire and the Short Form-36 at baseline and at 3, 6 and 12 months. A new analytic technique, the benefit statistic, was developed to facilitate inter-
Berger PB, Velianou JL, Vlachos HA, et al. on behalf of BARI Investigators. J Am Coll Cardiol 2001;38:1440 –9. Study Question: Do coronary artery bypass graft (CABG) and percutaneous transluminal coronary angioplasty (PTCA) confer equal survival benefit in a in high-risk anatomic subsets in which CABG improves survival compared with medical therapy (patients with three-vessel disease and two-vessel disease involving the proximal left anterior descending artery [LAD], particularly in the presence of left ventricular [LV] dysfunction)?
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pretability of disease-specific health status assessments over time. Results: Of the 99 patients assigned to medical therapy, 59 (60%) subsequently underwent transmyocardial revascularization. By an intention-to-treat analysis, patients initially randomized to transmyocardial revascularization had 44% of their angina eliminated vs. 21% for the medical treatment group (difference⫽23%; 95% confidence interval [CI], 11% to 34%). Differences in the benefits of transmyocardial revascularization on physical limitations (33% vs. 11% in the medical arm [difference⫽23%; 95% CI, 15% to 31%]) and quality of life (47% vs. 20% in the medical arm [difference⫽26%; 95% CI, 18% to 35%]) were similarly large. These benefits were apparent at 3 months and sustained throughout the 1 year of follow-up. An efficacy analysis that excluded patients who crossed over from the medical treatment to transmyocardial revascularization arm, suggested greater treatment benefits with TMLR. Conclusion: Transmyocardial revascularization may offer a valuable palliative alternative to patients with severe limitations in health status for whom no standard revascularization options exist. Perspective: No specific medical therapies were described in this paper. As such, it is difficult to interpret the benefits of transmyocardial revascularization. RM
1980s to the 1990s, the RR of reoperation after repair of AL-MVP vs. PL-MVP did not change, but the absolute rate of reoperation decreased similarly in PL-MVP and AL-MVP (at 10 years, from 10⫾3% to 5⫾2% and from 24⫾6% to 10⫾2%, respectively; p⫽0.04). Conclusion: In severe MR due to MVP, mitral valve repair compared with MVR provides improved very long-term survival after surgery for both AL-MVP and PL-MVP, with similar rates of reoperations after both procedures. Reoperation rates are more frequent after repair of AL-MVP than for PL-MVP. Perspective: Given the excellent long-term results of mitral valve repair compared to replacement, this is the procedure of choice for patients with severe MR due to MVP. However, it is unlikely that the excellent results obtained in this study at a center with a vast experience in this surgical approach can be achieved in centers performing just a few such procedures every year. RM
Does Histocompatibility Affect Homograft Valve Function After the Ross Procedure? Bechtel JFM, Bartels C, Schmidtke C, et al. Circulation 2001; 104 (Suppl I):I-25– 8. Study Question: Is there a relationship between the degree of histoincompatibility (defined as the number of human leukocyte antigen [HLA] mismatches between valve donor and recipient) or the provoked response of the recipient (measured by alloantibodies against HLA antigen) with echocardiographic parameters of homograft valve function after the Ross procedure? Methods: Twenty-six patients (mean age 41⫾14 years; 20 males, 6 females) and the cryopreserved pulmonary homograft valves that were implanted during a Ross procedure were typed for HLA-A, HLA-B and HLA-DR and alloantibodies to HLA class was measured. Results: Anti-HLA class I antibody was detected at follow-up (mean 15⫾6 months) in 14 (54%) of the patients at panel reactive antibody levels ⬎6% (considered positive). These antibodies were shown to be donor specific in all but one patient. Alloantibody-positive patients had a significantly higher HLA-A (p⫽0.008) and HLA-B (0.025) mismatches than alloantibody-negative patients. During follow-up, there was a significant increase of the maximal (16.2⫾7.1 mm Hg) and mean (13.2⫹4.3 mm Hg) transhomograft pressure gradients while homograft regurgitation did not change. The number of HLA mismatches or antibody status was found to have no significant impact on homograft valve function. Rather the implantation of a smaller size homograft (p⫽0.001) and younger recipient age (p⫽0.044) were shown to be significantly associated with increased transhomograft pressure gradients. Conclusion: Implantation of a cryopreserved pulmonary homograft during the Ross procedure can induce a specific humoral response. Neither this nor the degree of histocom-
Very Long-Term Survival and Durability of Mitral Valve Repair for Mitral Valve Prolapse Mohty D, Orszulak TA, Schaff HV, et al. Circulation 2001;104 (Suppl I):I-1–7. Study Question: What is the very long-term durability (10 years) of repair of the mitral valve for mitral regurgitation (MR) due to anterior leaflet prolapse (AL-MVP) and posterior leaflet prolapse (PL-MVP)? Methods: Patients (n⫽917, aged 65⫾13 years, 68% male) undergoing surgical correction of severe isolated MR due to MVP (679 repairs and 238 replacements [MVRs]) between 1980 and 1995 were evaluated to assess their long-term outcomes. Results: Survival after repair was better than survival after MVR for both PL-MVP (at 15 years, 41⫾5% vs. 31⫾6%, respectively; p⫽0.0003) and AL-MVP (at 14 years, 42⫾8% vs. 31⫾5%, respectively; p⫽0.003). In multivariate analysis adjusting for predictors of survival, repair was independently associated with lower mortality in PL-MVP (adjusted risk ratio [RR] 0.61, 95% CI 0.44 to 0.85; p⫽0.0034) and in AL-MVP (adjusted RR 0.67, 95% CI 0.47 to 0.96; p⫽0.028). The reoperation rate was not different after repair or MVR overall at 19 years (20⫾5% for repair vs. 23⫾5% for MVR; p⫽0.4) or separately in PL-MVP or AL-MVP. However, the reoperation rate was higher after repair of AL-MVP than after repair of PL-MVP (at 15 years, 28⫾7% vs. 11⫾3%, respectively; p⫽0.0006). From the
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Methods: In the Bypass Angioplasty Revascularization Investigation (BARI), 1829 patients with multivessel disease were randomized to an initial strategy of PTCA or CABG between 1988 and 1991. Stents and IIb/IIIa inhibitors were not utilized. Subsets of high-risk patients were evaluated to ascertain if the two reperfusions strategy conferred differential survival benefit. Results: Seven-year survival among patients with threevessel disease undergoing PTCA and CABG (n⫽754) was 79% vs. 84% (p⫽0.06), respectively, and 85% vs. 87% (p⫽0.36) when only non-diabetics (n⫽592) were analyzed. In patients with three-vessel disease and reduced LV function (ejection fraction ⬍50%), 7-year survival was similar in all PTCA and CABG patients (n⫽ 176, 70% vs. 74%; p⫽0.6) as well as among non-diabetics (n⫽124, 82% vs. 73%; p⫽0.29). Seven-year survival was also similar in all PTCA and CABG patients with two-vessel disease involving proximal LAD (n⫽352, 87% vs. 84%; p⫽0.9) and in nondiabetics with two-vessel disease involving proximal LAD and preserved LV function (n⫽287, 93% vs. 87%, p⫽0.27). In patients with two-vessel disease and reduced LV function, 7-year survival was also similar in all PTCA and CABG patients (n⫽72, 78% vs. 71%, p⫽0.7) as well as among non-diabetics (n⫽46, 90% vs. 67%, p⫽0.13). Conclusion: Revascularization by PTCA and CABG yielded equivalent survival over 7 years among high-risk anatomic subsets in which survival is prolonged by CABG vs. medical therapy. Perspective: These results suggesting similar 7-year survival with PTCA and CABG in high-risk patients should be viewed in light of the fact that only 12% of patients evaluated for BARI were randomized, most have preserved LV function and almost all had lesions that were amenable to either revascularization strategy. In addition, subgroup sample sizes at 7 years are sufficiently small to limit ability to detect modest survival differences. RM
Survival Following Coronary Angioplasty vs. Coronary Artery Bypass Surgery in Anatomic Subsets in Which Coronary Artery Bypass Surgery Improves Survival Compared With Medical Therapy. Results From the Bypass Angioplasty Revascularization Investigation (BARI)
Transmyocardial CO2 Laser Revascularization Improves Symptoms, Function, and Quality of Life: 12-Month Results From a Randomized Controlled Trial Spertus JA, Jones PG, Coen M, et al. Am J Med 2001;111:341– 8. Study Question: Are there differences in health status (symptoms, physical function and quality of life) between continued medical management and transmyocardial revascularization with a carbon dioxide laser in patients with severe, symptomatic, inoperable coronary artery disease? Methods: This prospective, multicenter trial randomized 98 patients to transmyocardial revascularization and 99 to continued medical therapy. Health status was assessed with the Seattle Angina Questionnaire and the Short Form-36 at baseline and at 3, 6 and 12 months. A new analytic technique, the benefit statistic, was developed to facilitate inter-
Berger PB, Velianou JL, Vlachos HA, et al. on behalf of BARI Investigators. J Am Coll Cardiol 2001;38:1440 –9. Study Question: Do coronary artery bypass graft (CABG) and percutaneous transluminal coronary angioplasty (PTCA) confer equal survival benefit in a in high-risk anatomic subsets in which CABG improves survival compared with medical therapy (patients with three-vessel disease and two-vessel disease involving the proximal left anterior descending artery [LAD], particularly in the presence of left ventricular [LV] dysfunction)?
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pretability of disease-specific health status assessments over time. Results: Of the 99 patients assigned to medical therapy, 59 (60%) subsequently underwent transmyocardial revascularization. By an intention-to-treat analysis, patients initially randomized to transmyocardial revascularization had 44% of their angina eliminated vs. 21% for the medical treatment group (difference⫽23%; 95% confidence interval [CI], 11% to 34%). Differences in the benefits of transmyocardial revascularization on physical limitations (33% vs. 11% in the medical arm [difference⫽23%; 95% CI, 15% to 31%]) and quality of life (47% vs. 20% in the medical arm [difference⫽26%; 95% CI, 18% to 35%]) were similarly large. These benefits were apparent at 3 months and sustained throughout the 1 year of follow-up. An efficacy analysis that excluded patients who crossed over from the medical treatment to transmyocardial revascularization arm, suggested greater treatment benefits with TMLR. Conclusion: Transmyocardial revascularization may offer a valuable palliative alternative to patients with severe limitations in health status for whom no standard revascularization options exist. Perspective: No specific medical therapies were described in this paper. As such, it is difficult to interpret the benefits of transmyocardial revascularization. RM
1980s to the 1990s, the RR of reoperation after repair of AL-MVP vs. PL-MVP did not change, but the absolute rate of reoperation decreased similarly in PL-MVP and AL-MVP (at 10 years, from 10⫾3% to 5⫾2% and from 24⫾6% to 10⫾2%, respectively; p⫽0.04). Conclusion: In severe MR due to MVP, mitral valve repair compared with MVR provides improved very long-term survival after surgery for both AL-MVP and PL-MVP, with similar rates of reoperations after both procedures. Reoperation rates are more frequent after repair of AL-MVP than for PL-MVP. Perspective: Given the excellent long-term results of mitral valve repair compared to replacement, this is the procedure of choice for patients with severe MR due to MVP. However, it is unlikely that the excellent results obtained in this study at a center with a vast experience in this surgical approach can be achieved in centers performing just a few such procedures every year. RM
Does Histocompatibility Affect Homograft Valve Function After the Ross Procedure? Bechtel JFM, Bartels C, Schmidtke C, et al. Circulation 2001; 104 (Suppl I):I-25– 8. Study Question: Is there a relationship between the degree of histoincompatibility (defined as the number of human leukocyte antigen [HLA] mismatches between valve donor and recipient) or the provoked response of the recipient (measured by alloantibodies against HLA antigen) with echocardiographic parameters of homograft valve function after the Ross procedure? Methods: Twenty-six patients (mean age 41⫾14 years; 20 males, 6 females) and the cryopreserved pulmonary homograft valves that were implanted during a Ross procedure were typed for HLA-A, HLA-B and HLA-DR and alloantibodies to HLA class was measured. Results: Anti-HLA class I antibody was detected at follow-up (mean 15⫾6 months) in 14 (54%) of the patients at panel reactive antibody levels ⬎6% (considered positive). These antibodies were shown to be donor specific in all but one patient. Alloantibody-positive patients had a significantly higher HLA-A (p⫽0.008) and HLA-B (0.025) mismatches than alloantibody-negative patients. During follow-up, there was a significant increase of the maximal (16.2⫾7.1 mm Hg) and mean (13.2⫹4.3 mm Hg) transhomograft pressure gradients while homograft regurgitation did not change. The number of HLA mismatches or antibody status was found to have no significant impact on homograft valve function. Rather the implantation of a smaller size homograft (p⫽0.001) and younger recipient age (p⫽0.044) were shown to be significantly associated with increased transhomograft pressure gradients. Conclusion: Implantation of a cryopreserved pulmonary homograft during the Ross procedure can induce a specific humoral response. Neither this nor the degree of histocom-
Very Long-Term Survival and Durability of Mitral Valve Repair for Mitral Valve Prolapse Mohty D, Orszulak TA, Schaff HV, et al. Circulation 2001;104 (Suppl I):I-1–7. Study Question: What is the very long-term durability (10 years) of repair of the mitral valve for mitral regurgitation (MR) due to anterior leaflet prolapse (AL-MVP) and posterior leaflet prolapse (PL-MVP)? Methods: Patients (n⫽917, aged 65⫾13 years, 68% male) undergoing surgical correction of severe isolated MR due to MVP (679 repairs and 238 replacements [MVRs]) between 1980 and 1995 were evaluated to assess their long-term outcomes. Results: Survival after repair was better than survival after MVR for both PL-MVP (at 15 years, 41⫾5% vs. 31⫾6%, respectively; p⫽0.0003) and AL-MVP (at 14 years, 42⫾8% vs. 31⫾5%, respectively; p⫽0.003). In multivariate analysis adjusting for predictors of survival, repair was independently associated with lower mortality in PL-MVP (adjusted risk ratio [RR] 0.61, 95% CI 0.44 to 0.85; p⫽0.0034) and in AL-MVP (adjusted RR 0.67, 95% CI 0.47 to 0.96; p⫽0.028). The reoperation rate was not different after repair or MVR overall at 19 years (20⫾5% for repair vs. 23⫾5% for MVR; p⫽0.4) or separately in PL-MVP or AL-MVP. However, the reoperation rate was higher after repair of AL-MVP than after repair of PL-MVP (at 15 years, 28⫾7% vs. 11⫾3%, respectively; p⫽0.0006). From the
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