Catheterization and Cardiovascular Interventions 83:905–906 (2014)
Editorial Comment Routine Postdilation of DrugEluting Stents: Worth the Gain John Fani Srour, MD and J. Dawn Abbott,* MD, FSCAI Division of Cardiology, Warren Alpert Medical School, Brown University, Providence, Rhode Island
Despite significant advances in stent technology, the semicompliant balloons used in stent delivery systems may not be sufficient for desired stent expansion [1]. Adjunctive high-pressure dilatation using a noncompliant balloon, therefore, can improve on minimal luminal stent diameter and strut apposition to the vessel wall. Optimization of stent deployment has the potential to decrease in stent restenosis and thrombosis rates, thus reducing target vessel revascularization. However, in the major randomized trials of drug-eluting stents (DES), postdilation was not routinely performed and the effect on clinical outcomes remains unclear. Currently, postdilatation rates are highly dependent on individual operators, with some advocating routine use and other reserving for a suboptimal poststent angiographic result or complex anatomy including calcification, bifurcations, or chronic occlusions. In the DEScover Registry, involving 6,509 patients treated with a first generation DES in routine practice in the United States, postdilatation was performed in 46% of patients. Potential drawbacks of postdilatation include resource utilization and complications. The procedure, albeit generally technically straightforward, can result in edge dissection, geographic miss, no reflow, or longitudinal stent deformation. Vessel trauma from high pressure can also lead to a greater injury response and potential for restenosis [2]. Increased cost, procedural and fluoroscopy time, and contrast use are also considerations. In this issue of the journal, Pasceri et al. astutely present their single center experience with routine highpressure, noncompliant balloon inflation following DES placement [3]. A strategy of universal postdilatation was instituted in 2009 with the exception of procedures guided by intravascular ultrasound and in patients with ST elevation myocardial infarction or vein graft intervention; where the risk of no reflow was a concern. The present analysis compares the first 279 patients in the routine postdilatation period to 262 patients treated in the 6 months prior to adopting the change in practice C 2014 Wiley Periodicals, Inc. V
when postdilatation was performed per the operators’ discretion. In the routine postdilatation patients, a noncompliant balloon sized 0.25 mm bigger than the stent diameter was inflated to 14 atm or higher for a minimum of 10 s and the entire length of the stent was treated. Only 32% of the “standard treatment” group underwent postdilatation and in the majority a segment rather than the entire stent length was treated. Except for the number of stents placed which was slighter higher in the routine postdilatation group, there were no significant differences in baseline, clinical, or angiographic, characteristics between study populations. As compared to the standard group, stents in the routine postdilatation cohort were expanded by a larger mean balloon diameter (3.09 vs. 3.25 mm) using a higher mean maximal pressure (14.8 vs. 16.8 atm). Routine postdilatation was associated with a small but significant improvement in acute gain (1.66 vs. 1.59 mm, P ¼ 0.001) and final minimal luminal diameter. With respect to clinical endpoints at 12 months, the incidence of major adverse cardiac events was 19.5% in the standard treatment group and 12.5% in the routine postdilatation group (P ¼ 0.04); mainly driven by lower rates of target lesion revascularization. However, the two cohorts did not differ in the incidence of myocardial infarction, including periprocedural events. The mortality rate was 0% and the study was not powered for stent thrombosis, however, the rate was 1.1 and 0% in the standard and routine postdilatation groups, respectively. Multivariable analysis using propensity-score models confirmed the significant association between the use of routine postdilatation and reduction of major adverse cardiac events with a 48% lower risk. The results of the study suggest an impressive benefit with routine postdilatation of DES but several issues are
Conflict of Interest: Nothing to report. *Correspondence to: J. Dawn Abbott, MD, FSCAI, Associate Professor of Medicine, Cardiovascular Institute, Rhode Island Hospital, Warren Alpert Medical School, Brown University, 814 APC, 593 Eddy Street, Providence, RI. E-mail: [email protected] Received 8 March 2014; Revision accepted 10 March 2014 DOI: 10.1002/ccd.25481 Published online 21 April 2014 in Wiley Online Library (wileyonlinelibrary.com)
906
Srour and Abbott
worth further discussion. This is not a nonrandomized comparison, however, the sequential rather than simultaneous adoption of a routine postdilatation strategy versus a selective strategy limits bias introduced by operators and is a strength of this study. The study was not large enough to examine whether the routine postdilatation strategy benefited all subgroups such as those treated with newer DES, as over 50% of patients received sirolimus and paclitaxel-eluting stents. Stent distensibility and response to high-pressure balloon inflation is different among various generations owing to different stent platform materials and designs [4]. The study did not examine optimal sizing of the postdilation balloon or use intravascular imaging the assess the response to postdilation. The quantitative coronary analysis was not performed by a core lab and its unclear if the interventionalist performing the measurements was blinded to treatment time period. Moreover, the routine use of universal stress testing at 6–8 months after coronary intervention may have increased the rate of target lesion revascularization and thus biased the results. The practice of routine postdilatation of stents is not currently advocated by major guidelines. Whether the results of the study are reproducible without routine postprocedure stress testing remains unknown. In an era of cost containment, studies of postdilation must show a significant effect on hard clinical end points before indiscriminate adoption can be recommended. The same argument prevents the widespread use of intravascular ultrasound for refining stent deployment in all subjects and lesions; especially when randomized studies failed to demonstrate significant clinical benefit even in complex lesions [5]. Consequently, even acknowledging the limitation of angiography for determining stent expansion, a more selective postdilatation
approach is probably more practical. This would include lesions with calcification or large plaque burden which are expected to have high resistance to dilatation. Additionally, routine postdilatation of lesions at higher risk for restenosis such as small vessels, diffuse disease, overlapping stents, in stent restenosis, and patients with diabetes mellitus is reasonable. In summary, the findings of the current study are important and heighten the awareness of the need to optimize procedural outcomes and when in doubt postdilatation should be carried out. REFERENCES 1. Cheneau E, Satler LF, Escolar E, Suddath WO, Kent KM, Weissman NJ, Waksman R, Pichard AD. Underexpansion of sirolimus-eluting stents: Incidence and relationship to delivery pressure. Catheter Cardiovasc Interv 2005;65:222–226. 2. Frobert O, Sarno G, James SK, Saleh N, Lagerqvist B. Effect of stent inflation pressure and post-dilatation on the outcome of coronary artery intervention. A report of more than 90,000 stent implantations. PLoS One 2013;8:e56348. 3. Pasceri V, Pelliccia F, Pristipino C, Roncella A, Irini D, Varveri A, Bisciglia A, Speciale G. Clinical effects of routine postdilatation of drug-eluting stents. Catheter Cardiovasc Interv 2014;83: 898–904. 4. Park SM, Kim JS, Ko YG, Choi D, Hong MK, Jang Y, Kang WC, Ahn T, Kim BK, Oh SJ, Jeon DW, Yang JY. Angiographic and intravascular ultrasound follow up of paclitaxel- and sirolimus-eluting stent after poststent high-pressure balloon dilation: From the poststent optimal stent expansion trial. Catheter Cardiovasc Interv 2011;77:15–21. 5. Chieffo A, Latib A, Caussin C, Presbitero P, Galli S, Menozzi A, Varbella F, Mauri F, Valgimigli M, Arampatzis C, Sabate M, Erglis A, Reimers B, Airoldi F, Laine M, Palop RL, Mikhail G, Maccarthy P, Romeo F, Colombo A. A prospective, randomized trial of intravascular-ultrasound guided compared to angiography guided stent implantation in complex coronary lesions: The AVIO trial. Am Heart J 2013;165:65–72.
Catheterization and Cardiovascular Interventions DOI 10.1002/ccd. Published on behalf of The Society for Cardiovascular Angiography and Interventions (SCAI).
Editorial Comment Routine Postdilation of DrugEluting Stents: Worth the Gain John Fani Srour, MD and J. Dawn Abbott,* MD, FSCAI Division of Cardiology, Warren Alpert Medical School, Brown University, Providence, Rhode Island
Despite significant advances in stent technology, the semicompliant balloons used in stent delivery systems may not be sufficient for desired stent expansion [1]. Adjunctive high-pressure dilatation using a noncompliant balloon, therefore, can improve on minimal luminal stent diameter and strut apposition to the vessel wall. Optimization of stent deployment has the potential to decrease in stent restenosis and thrombosis rates, thus reducing target vessel revascularization. However, in the major randomized trials of drug-eluting stents (DES), postdilation was not routinely performed and the effect on clinical outcomes remains unclear. Currently, postdilatation rates are highly dependent on individual operators, with some advocating routine use and other reserving for a suboptimal poststent angiographic result or complex anatomy including calcification, bifurcations, or chronic occlusions. In the DEScover Registry, involving 6,509 patients treated with a first generation DES in routine practice in the United States, postdilatation was performed in 46% of patients. Potential drawbacks of postdilatation include resource utilization and complications. The procedure, albeit generally technically straightforward, can result in edge dissection, geographic miss, no reflow, or longitudinal stent deformation. Vessel trauma from high pressure can also lead to a greater injury response and potential for restenosis [2]. Increased cost, procedural and fluoroscopy time, and contrast use are also considerations. In this issue of the journal, Pasceri et al. astutely present their single center experience with routine highpressure, noncompliant balloon inflation following DES placement [3]. A strategy of universal postdilatation was instituted in 2009 with the exception of procedures guided by intravascular ultrasound and in patients with ST elevation myocardial infarction or vein graft intervention; where the risk of no reflow was a concern. The present analysis compares the first 279 patients in the routine postdilatation period to 262 patients treated in the 6 months prior to adopting the change in practice C 2014 Wiley Periodicals, Inc. V
when postdilatation was performed per the operators’ discretion. In the routine postdilatation patients, a noncompliant balloon sized 0.25 mm bigger than the stent diameter was inflated to 14 atm or higher for a minimum of 10 s and the entire length of the stent was treated. Only 32% of the “standard treatment” group underwent postdilatation and in the majority a segment rather than the entire stent length was treated. Except for the number of stents placed which was slighter higher in the routine postdilatation group, there were no significant differences in baseline, clinical, or angiographic, characteristics between study populations. As compared to the standard group, stents in the routine postdilatation cohort were expanded by a larger mean balloon diameter (3.09 vs. 3.25 mm) using a higher mean maximal pressure (14.8 vs. 16.8 atm). Routine postdilatation was associated with a small but significant improvement in acute gain (1.66 vs. 1.59 mm, P ¼ 0.001) and final minimal luminal diameter. With respect to clinical endpoints at 12 months, the incidence of major adverse cardiac events was 19.5% in the standard treatment group and 12.5% in the routine postdilatation group (P ¼ 0.04); mainly driven by lower rates of target lesion revascularization. However, the two cohorts did not differ in the incidence of myocardial infarction, including periprocedural events. The mortality rate was 0% and the study was not powered for stent thrombosis, however, the rate was 1.1 and 0% in the standard and routine postdilatation groups, respectively. Multivariable analysis using propensity-score models confirmed the significant association between the use of routine postdilatation and reduction of major adverse cardiac events with a 48% lower risk. The results of the study suggest an impressive benefit with routine postdilatation of DES but several issues are
Conflict of Interest: Nothing to report. *Correspondence to: J. Dawn Abbott, MD, FSCAI, Associate Professor of Medicine, Cardiovascular Institute, Rhode Island Hospital, Warren Alpert Medical School, Brown University, 814 APC, 593 Eddy Street, Providence, RI. E-mail: [email protected] Received 8 March 2014; Revision accepted 10 March 2014 DOI: 10.1002/ccd.25481 Published online 21 April 2014 in Wiley Online Library (wileyonlinelibrary.com)
906
Srour and Abbott
worth further discussion. This is not a nonrandomized comparison, however, the sequential rather than simultaneous adoption of a routine postdilatation strategy versus a selective strategy limits bias introduced by operators and is a strength of this study. The study was not large enough to examine whether the routine postdilatation strategy benefited all subgroups such as those treated with newer DES, as over 50% of patients received sirolimus and paclitaxel-eluting stents. Stent distensibility and response to high-pressure balloon inflation is different among various generations owing to different stent platform materials and designs [4]. The study did not examine optimal sizing of the postdilation balloon or use intravascular imaging the assess the response to postdilation. The quantitative coronary analysis was not performed by a core lab and its unclear if the interventionalist performing the measurements was blinded to treatment time period. Moreover, the routine use of universal stress testing at 6–8 months after coronary intervention may have increased the rate of target lesion revascularization and thus biased the results. The practice of routine postdilatation of stents is not currently advocated by major guidelines. Whether the results of the study are reproducible without routine postprocedure stress testing remains unknown. In an era of cost containment, studies of postdilation must show a significant effect on hard clinical end points before indiscriminate adoption can be recommended. The same argument prevents the widespread use of intravascular ultrasound for refining stent deployment in all subjects and lesions; especially when randomized studies failed to demonstrate significant clinical benefit even in complex lesions [5]. Consequently, even acknowledging the limitation of angiography for determining stent expansion, a more selective postdilatation
approach is probably more practical. This would include lesions with calcification or large plaque burden which are expected to have high resistance to dilatation. Additionally, routine postdilatation of lesions at higher risk for restenosis such as small vessels, diffuse disease, overlapping stents, in stent restenosis, and patients with diabetes mellitus is reasonable. In summary, the findings of the current study are important and heighten the awareness of the need to optimize procedural outcomes and when in doubt postdilatation should be carried out. REFERENCES 1. Cheneau E, Satler LF, Escolar E, Suddath WO, Kent KM, Weissman NJ, Waksman R, Pichard AD. Underexpansion of sirolimus-eluting stents: Incidence and relationship to delivery pressure. Catheter Cardiovasc Interv 2005;65:222–226. 2. Frobert O, Sarno G, James SK, Saleh N, Lagerqvist B. Effect of stent inflation pressure and post-dilatation on the outcome of coronary artery intervention. A report of more than 90,000 stent implantations. PLoS One 2013;8:e56348. 3. Pasceri V, Pelliccia F, Pristipino C, Roncella A, Irini D, Varveri A, Bisciglia A, Speciale G. Clinical effects of routine postdilatation of drug-eluting stents. Catheter Cardiovasc Interv 2014;83: 898–904. 4. Park SM, Kim JS, Ko YG, Choi D, Hong MK, Jang Y, Kang WC, Ahn T, Kim BK, Oh SJ, Jeon DW, Yang JY. Angiographic and intravascular ultrasound follow up of paclitaxel- and sirolimus-eluting stent after poststent high-pressure balloon dilation: From the poststent optimal stent expansion trial. Catheter Cardiovasc Interv 2011;77:15–21. 5. Chieffo A, Latib A, Caussin C, Presbitero P, Galli S, Menozzi A, Varbella F, Mauri F, Valgimigli M, Arampatzis C, Sabate M, Erglis A, Reimers B, Airoldi F, Laine M, Palop RL, Mikhail G, Maccarthy P, Romeo F, Colombo A. A prospective, randomized trial of intravascular-ultrasound guided compared to angiography guided stent implantation in complex coronary lesions: The AVIO trial. Am Heart J 2013;165:65–72.
Catheterization and Cardiovascular Interventions DOI 10.1002/ccd. Published on behalf of The Society for Cardiovascular Angiography and Interventions (SCAI).
