Evaluation of Angiography-Guided Coronary Stent Implementation
Evaluation of Angiography-Guided Coronary Stent Implementation
Background: High inflation pressure (HP) after coronary stent deployment has become a standard approach because it has been associated with a decreased subacute stent thrombosis (SAT) rate. However, the impact of HP on long-term outcomes is still unclear. We compared the long-term results of a strategy of increasing HP (
12 atm) until the achievement of angiographic success (<20% residual stenosis) with a prespecified very high inflation pressure (VHP) strategy of 20 atm without intermediate inflations.
Methods and Results: We conducted a parallel-group, nonrandomized study to evaluate the short- and long-term results in 136 consecutive eligible patients who underwent successful single Palmaz-Schatz stent implantation in vessels
3 mm. Major adverse cardiac events (MACE), that is, death, myocardial infarction, and target lesion revascularization (TLR), were monitored for a minimum of 6 months. No significant differences were observed between the two strategies in terms of final minimal lumen diameter (HP, 3.0 ± 0.5 vs VHP, 3.1 ± 0.5 mm) and acute gain (HP, 2.1 ± 0.7 vs VHP, 2.2 ± 0.6). The overall rate of subacute stent thrombosis was 0.7%. During a 405 ± 148-day follow-up, 21 (28.8%) patients in the VHP group and 6 (9.5%) in the HP group ( P = .005) had MACE, with a TLR rate of 27.4% versus 7.9% ( P = .009), respectively. By multivariate analysis, the use of VHP increased the odds of long-term MACE by a factor of 3.48 ( P = .009). Among patients undergoing TLR, those treated with VHP had a greater lumen loss (HP, 1.83 ± 0.57 vs VHP, 2.15 ± 0.36 mm, P = .02) and a more frequent pattern of diffuse restenosis (71% vs 16%, P = .06).
Conclusions: In our study, the two strategies had similar acute and short-term results, but VHP was associated with a poorer long-term outcome. These data provide a rationale for a less aggressive strategy for stent deployment by optimizing rather than attempting to maximize inflation pressure and stent expansion.
The use of high inflation pressure after coronary stent deployment appears to have reduced the incidence of subacute stent thrombosis (SAT). A seminal study by Colombo et al showed by intravascular ultrasound that after many angiographically successful stent procedures there was a relative underexpansion of the stent and in some cases lack of apposition of stent struts to the vessel wall. Further balloon inflations with pressures >14 atm produced an increase in stent cross-sectional area without an appreciable change angiographically. This strategy resulted in an SAT rate of <1%, which has been replicated in more recent studies that used high pressures without intravascular ultrasound. Furthermore, the angiographic minimal lumen diameter (MLD) has been shown to be a strong inverse predictor of restenosis, leading to the "bigger is better" paradigm. Thus it may be considered that stenting with high pressures, through greater lumen enlargement, could also favorably affect the long-term clinical outcome. Conversely, data suggest that aggressive stent implantation with high pressure may be associated with deeper injury to the vessel wall, which in turn may increase the neointimal proliferative response, resulting in a greater late lumen loss and an increased risk of restenosis and major adverse cardiac events (MACE). These considerations provide a rationale for a strategy aimed at minimizing vascular injury by optimizing rather than maximizing balloon inflation pressure while adequately expanding the stent. This prospective, nonrandomized study was designed to evaluate the safety and long-term results of 2 inflation strategies after Palmaz-Schatz stent deployment with angiographic guidance only. The first strategy used increasing high inflation pressures (HP)
12 atm until the achievement of angiographic success; the second used a prespecified very high inflation pressure (VHP) of 20 atm in an attempt to widely expand the stent without the need for intermediate inflations.
Background: High inflation pressure (HP) after coronary stent deployment has become a standard approach because it has been associated with a decreased subacute stent thrombosis (SAT) rate. However, the impact of HP on long-term outcomes is still unclear. We compared the long-term results of a strategy of increasing HP (
12 atm) until the achievement of angiographic success (<20% residual stenosis) with a prespecified very high inflation pressure (VHP) strategy of 20 atm without intermediate inflations.
Methods and Results: We conducted a parallel-group, nonrandomized study to evaluate the short- and long-term results in 136 consecutive eligible patients who underwent successful single Palmaz-Schatz stent implantation in vessels
3 mm. Major adverse cardiac events (MACE), that is, death, myocardial infarction, and target lesion revascularization (TLR), were monitored for a minimum of 6 months. No significant differences were observed between the two strategies in terms of final minimal lumen diameter (HP, 3.0 ± 0.5 vs VHP, 3.1 ± 0.5 mm) and acute gain (HP, 2.1 ± 0.7 vs VHP, 2.2 ± 0.6). The overall rate of subacute stent thrombosis was 0.7%. During a 405 ± 148-day follow-up, 21 (28.8%) patients in the VHP group and 6 (9.5%) in the HP group ( P = .005) had MACE, with a TLR rate of 27.4% versus 7.9% ( P = .009), respectively. By multivariate analysis, the use of VHP increased the odds of long-term MACE by a factor of 3.48 ( P = .009). Among patients undergoing TLR, those treated with VHP had a greater lumen loss (HP, 1.83 ± 0.57 vs VHP, 2.15 ± 0.36 mm, P = .02) and a more frequent pattern of diffuse restenosis (71% vs 16%, P = .06).
Conclusions: In our study, the two strategies had similar acute and short-term results, but VHP was associated with a poorer long-term outcome. These data provide a rationale for a less aggressive strategy for stent deployment by optimizing rather than attempting to maximize inflation pressure and stent expansion.
The use of high inflation pressure after coronary stent deployment appears to have reduced the incidence of subacute stent thrombosis (SAT). A seminal study by Colombo et al showed by intravascular ultrasound that after many angiographically successful stent procedures there was a relative underexpansion of the stent and in some cases lack of apposition of stent struts to the vessel wall. Further balloon inflations with pressures >14 atm produced an increase in stent cross-sectional area without an appreciable change angiographically. This strategy resulted in an SAT rate of <1%, which has been replicated in more recent studies that used high pressures without intravascular ultrasound. Furthermore, the angiographic minimal lumen diameter (MLD) has been shown to be a strong inverse predictor of restenosis, leading to the "bigger is better" paradigm. Thus it may be considered that stenting with high pressures, through greater lumen enlargement, could also favorably affect the long-term clinical outcome. Conversely, data suggest that aggressive stent implantation with high pressure may be associated with deeper injury to the vessel wall, which in turn may increase the neointimal proliferative response, resulting in a greater late lumen loss and an increased risk of restenosis and major adverse cardiac events (MACE). These considerations provide a rationale for a strategy aimed at minimizing vascular injury by optimizing rather than maximizing balloon inflation pressure while adequately expanding the stent. This prospective, nonrandomized study was designed to evaluate the safety and long-term results of 2 inflation strategies after Palmaz-Schatz stent deployment with angiographic guidance only. The first strategy used increasing high inflation pressures (HP)
12 atm until the achievement of angiographic success; the second used a prespecified very high inflation pressure (VHP) of 20 atm in an attempt to widely expand the stent without the need for intermediate inflations.
Source...