Comment
Biodegradable stents: the golden future of angioplasty? Key steps in the biodegradable stent revolution, including the first-in-man results of magnesium1,2 and poly-L-lactide (PLLA) stents,3,4 have been reported in The Lancet. With more than 60 000 Absorb bioresorbable vascular scaffolds implanted in the past 3 years, a randomised comparison of metallic and fully bioabsorbable stents, both eluting the antiproliferative drug everolimus, is now presented by Patrick Serruys and colleagues.5 The ABSORB II trial had a 2:1 single-masked design and a small sample population of 501 patients, with sophisticated coprimary endpoints of nitrate-induced vasomotion and changes in minimum lumen diameter (in-stent late loss) at 3 years. The results, presented are limited to secondary outcomes after 1 year of clinical follow-up, but address what matters most to patients and physicians—symptoms and adverse events— and include an elaborate analysis of procedural results including data from quantitative coronary angiography and intravascular ultrasound. In ABSORB II, the Absorb bioresorbable scaffold and the Xience metallic stent were associated with very low and similar mortality, and target lesion revascularisation, at 1 year: the composite of cardiac death, target-vessel myocardial infarction, and clinically indicated targetlesion revascularisation occurred in 16 (5%) patients in the Absorb group vs five (3%) patients in the Xience group (difference 1·80%, 95% CI –2·48 to 5·16); and 1-year probable or definite stent thrombosis was recorded in three (0·9%) patients versus no patients (0·91%, –1·45 to 2·65). The authors conclude that the “everolimuseluting bioresorbable scaffold showed similar 1-year composite secondary clinical outcomes to the everolimuseluting metallic stent”, but this conclusion is probably an overstatement because the study was not powered to test non-inferiority of clinical adverse events. To focus on stent thrombosis, the findings show a small numerical difference against the bioresorbable scaffold (three cases vs no cases in the metallic stent group). Because stent thrombosis is a catastrophic complication that results in death and myocardial infarction in most cases, and the study enrolled so-called simple lesions of an average length of 20 mm, a difference of 0·91% might represent a genuine clinically worrisome signal. The reliable detection of a statistically meaningful difference, however, would need a much larger sample size, far larger than the 2250 patients enrolled in the
ongoing US ABSORB III trial (NCT01751906). Findings from registry studies of bioresorbable stents (dealing with patients and lesions of greater complexity, including ST-segment myocardial infarction, very long lesions, and bifurcations) have shown high rates of stent thrombosis at 6–12 months (3·0%,6 2·1%,7 2·2%,8 2·5%,9 and 2·7%10). These percentages seem to be much higher than the 1-year rates of stent thrombosis reported for secondgeneration drug-eluting stents in a network metaanalysis of more than 25 000 patients, including patients in all-comers trials.11 Bioresorbable scaffolds have been introduced to reduce and possibly eliminate late stent thrombosis, by avoiding the presence of a permanent metallic foreign body. An explanation for the apparent excess of thrombosis events in patients with bioresorbable stents in ABSORB II might come from the different postprocedural quantitive angiography and intravascular ultrasound results reported for the two stent treatments. Final in-stent minimum lumen diameter and intravascular ultrasound minimum lumen cross-sectional area were significantly smaller in the Absorb group than in the Xience group. The average minimum area of 4·89 mm² for the bioresorbable scaffold (compared with 5·73 mm² for the metallic stent) is close to or lower than the cutoff measurements suggested by many intravascular ultrasound studies as predictive of drug-eluting stent failure (thrombosis and restenosis).12,13 The investigators did not use Rotablator, cutting balloon, or high-pressure 1:1 balloon-to-artery ratio dilatation for lesion preparation; postdilatation was discouraged, resulting in a low final deployment pressure (14·23 atm for the bioresorbable scaffold vs 15·03 atm for the metallic stent, p=0·01) and intravascular ultrasound was purely documentary. Similarly, in registry studies of bioresorbable scaffolds (with rates of stent thrombosis of 2–3%) postdilatation was used in about half of cases, with final dilatation pressures of less than 15 atm and rare use of intravascular imaging guidance.6–8 Findings from other real-world studies14–16 actively using intravascular imaging and high-pressure postdilatation have not shown any stent thrombosis, suggesting that the implantation technique rather than the scaffold itself is to blame. Non-inferiority for rare adverse events is very difficult to show, and is certainly not a powerful
www.thelancet.com Published online September 14, 2014 http://dx.doi.org/10.1016/S0140-6736(14)61636-6
Published Online September 14, 2014 http://dx.doi.org/10.1016/ S0140-6736(14)61636-6 See Online/Articles http://dx.doi.org/10.1016/ S0140-6736(14)61455-0
1
Comment
motivation to switch to a bioresorbable scaffold from a well tested, less expensive, gold-standard treatment. Serruys and colleagues5 must be commended for a careful assessment of residual or recurrent angina, studied with the well-validated Seattle questionnaire and with an exercise test on a treadmill or bicycle. The perfect superimposition of results at 1 year offers convincing objective evidence of a similar symptomatic improvement, a logical outcome if ischaemia is expected to be determined by the lumen area achieved rather than the type of stent used. The presence of a statistically significant difference in a post-hoc analysis of angina episodes after discharge (16% in the bioresorbable scaffold group vs 26% in the metallic stent group, p=0·01)—reported by investigators aware of treatment allocation—is much weaker evidence than exercise duration, ECG changes, symptoms developing during maximum exercise, or A
B
D
C
C
D
B
E
F
G I
H
H
I
G
J
*Carlo Di Mario, Gianluca Caiazzo
Figure: Late in-scaffold thrombosis Top panel shows late (6 months) in-scaffold thrombosis with angiographic evidence of total occlusion of the left anterior descending artery (A).Optical coherence tomography performed after thrombectomy showed a large distal reference segment (B), clear under-expansion of the bioresorbable scaffold (area= 1·73 mm²) in the mid-segment (C) where a previously implanted stent is visible, and a well-expanded bioresorbable scaffold in the proximal segment (D). The longitudinal view emphasises the localisation of the various cross-sections (E). Bottom panel shows angiographic final result after additional high-pressure dilatation to 38 atm with a 3·0 mm non-compliant balloon and prolonged drug-eluting balloon dilatation (F). Optical coherence tomography showed an unchanged distal vessel (distal reference, G), a larger minimum cross-sectional area in the mid-segment (H) and a minimally larger proximal segment (I).The longitudinal view emphasises the uniform dilatation of the scaffolded mid-segment (J).
2
results of a questionnaire completed by patients still masked to treatment allocation. Internists and particularly cardiologists are spoilt by the availability of large outcome trials guiding them in their decisions. If a new implantable biodegradable instrument delivered the same 1-year results as a conventional metallic hip prosthesis, potentially sparing the risks of the persistence of a large permanent foreign body, what evidence would orthopaedic surgeons (and their patients) require to persuade them to switch to the new technique? Perhaps now cardiologists need to understand that the small incremental benefits of new interventional devices cannot be confirmed by conventional large outcome trials; sometimes decisions must be taken without the comfort of statistical significance. For biodegradable stents, the concerns raised by the possible increase in stent thrombosis need to be dispelled by data from sufficiently large observational studies, confirming that bioresorbable scaffolds can deliver the same results as secondgeneration drug eluting stents with the appropriate implantation technique. Pioneers carefully following up their patients, clinically and with repeated imaging, have provided compelling evidence that favourable remodelling and restoration of vasomotion is obtained after 2–5 years.4,17 Still, a larger body of long-term data is needed, and the regulatory approval process in this initial phase should impose long-term surveillance and a consent process for patients that clarifies the experimental nature of bioresorbable scaffolds. Prudence and careful monitoring are essential in the adoption of a potentially revolutionary technique. However, we cannot halt the progress of interventional cardiology while waiting for unattainable megatrials.
Cardiovascular National Institute of Health Research Biomedical Research Unit, Royal Brompton & Harefield NHS Foundation Trust, London SW3 6NP, UK (CDM, GC); and Division of Cardiology, Department of Medical and Surgical Sciences, “Magna Graecia” University, Catanzaro, Italy (GC) [email protected] CDM has received research funding from Abbott Vascular via his institution. GC declares no competing interests. 1
2
Erbel R, Di Mario C, Bartunek J, et al. Temporary scaffolding of coronary arteries with bioabsorbable magnesium stents: a prospective, nonrandomised multicentre trial. Lancet 2007; 369: 1869–75. Haude M, Erbel R, Erne P, et al. Safety and performance of the drug-eluting absorbable metal scaffold (DREAMS) in patients with de-novo coronary lesions: 12 month results of the prospective, multicentre, first-in-man BIOSOLVE-I trial. Lancet 2013; 381: 836–44.
www.thelancet.com Published online September 14, 2014 http://dx.doi.org/10.1016/S0140-6736(14)61636-6
Comment
3
4
5
6
7
8 9
10
Ormiston JA, Serruys PW, Regar E, et al. A bioabsorbable everolimus-eluting coronary stent system for patients with single de-novo coronary artery lesions (ABSORB): a prospective open-label trial. Lancet 2008; 371: 899–907. Serruys PW, Ormiston JA, Onuma Y, et al. A bioabsorbable everolimuseluting coronary stent system (ABSORB): 2-year outcomes and results from multiple imaging methods. Lancet 2009; 373: 897–910. Serruys PW, Chevalier B, Dudek D, et al. A bioresorbable everolimus-eluting scaffold versus a metallic everolimus-eluting stent for ischaemic heart disease caused by de-novo native coronary artery lesions (ABSORB II): an interim 1-year analysis of clinical and procedural secondary outcomes from a randomised controlled trial. Lancet 2014; published online Sept 14. http://dx.doi.org/10.1016/S0140-6736(14)61455-0. Kraak RP, Hassell ME, Grundeken MJ, et al. Initial experience and clinical evaluation of the Absorb bioresorbable vascular scaffold (BVS) in real-world practice: the AMC Single Centre Real World PCI Registry. EuroIntervention 2014; published online Aug 20. DOI:10.4244/ EIJY14M08_08. Capodanno D, Gori T, Nef H, et al. Percutaneous coronary intervention with everolimus-eluting bioresorbable vascular scaffolds in routine clinical practice: early and midterm outcomes from the European multicentre GHOST-EU registry. EuroIntervention 2014; published online July 18. DOI:10.4244/EIJY14M07_11. van Geuns RJ. EuroPCR2014. http://www.pcronline.com/Lectures/2014/ BVS-Expand-6-month-results (accessed Sept 8, 2014). Kočka V, Malý M, Toušek P, et al. Bioresorbable vascular scaffolds in acute ST-segment elevation myocardial infarction: a prospective multicentre study ’Prague 19’. Eur Heart J 2014; 35: 787–94. Gori T, Schulz E, Hink U, et al. Early outcome after implantation of Absorb bioresorbable drug-eluting scaffolds in patients with acute coronary syndromes. EuroIntervention 2014; 9: 1036–41.
11
12
13
14
15
16
17
Kang SH, Park KW, Kang DY, et al. Biodegradable-polymer drug-eluting stents vs. bare metal stents vs. durable-polymer drug-eluting stents: a systematic review and Bayesian approach network meta-analysis. Eur Heart J 2014; 35: 1147–58. Fujii K, Carlier SG, Mintz GS, et al. Stent underexpansion and residual reference segment stenosis are related to stent thrombosis after sirolimuseluting stent implantation: an intravascular ultrasound study. J Am Coll Cardiol 2005; 45: 995–98. Doi H, Maehara A, Mintz GS, et al. Impact of post-intervention minimal stent area on 9-month follow-up patency of paclitaxel-eluting stents: an integrated intravascular ultrasound analysis from the TAXUS IV, V, and VI and TAXUS ATLAS Workhorse, Long Lesion, and Direct Stent Trials. JACC Cardiovasc Interv 2009; 2: 1269–75. Mattesini A, Secco GG, Dall’Ara G, et al. ABSORB biodegradable stents versus second-generation metal stents: a comparison study of 100 complex lesions treated under OCT guidance. JACC Cardiovasc Interv 2014; 7: 741–50. Brown AJ, McCormick LM, Braganza DM, Bennett MR, Hoole SP, West NE. Expansion and malapposition characteristics after bioresorbable vascular scaffold implantation. Catheter Cardiovasc Interv 2014; 84: 37–45. Costopoulos C, Latib A, Naganuma T, et al. Comparison of early clinical outcomes between absorb bioresorbable vascular scaffold and everolimuseluting stent implantation in a real-world population. Catheter Cardiovasc Interv 2014; published online June 6. DOI:10.1002/ ccd.25569. Onuma Y, Dudek D, Thuesen L, et al. Five-year clinical and functional multislice computed tomography angiographic results after coronary implantation of the fully resorbable polymeric everolimus-eluting scaffold in patients with de novo coronary artery disease: the ABSORB cohort A trial. JACC Cardiovasc Interv 2013; 6: 999–1009.
www.thelancet.com Published online September 14, 2014 http://dx.doi.org/10.1016/S0140-6736(14)61636-6
3
Biodegradable stents: the golden future of angioplasty? Key steps in the biodegradable stent revolution, including the first-in-man results of magnesium1,2 and poly-L-lactide (PLLA) stents,3,4 have been reported in The Lancet. With more than 60 000 Absorb bioresorbable vascular scaffolds implanted in the past 3 years, a randomised comparison of metallic and fully bioabsorbable stents, both eluting the antiproliferative drug everolimus, is now presented by Patrick Serruys and colleagues.5 The ABSORB II trial had a 2:1 single-masked design and a small sample population of 501 patients, with sophisticated coprimary endpoints of nitrate-induced vasomotion and changes in minimum lumen diameter (in-stent late loss) at 3 years. The results, presented are limited to secondary outcomes after 1 year of clinical follow-up, but address what matters most to patients and physicians—symptoms and adverse events— and include an elaborate analysis of procedural results including data from quantitative coronary angiography and intravascular ultrasound. In ABSORB II, the Absorb bioresorbable scaffold and the Xience metallic stent were associated with very low and similar mortality, and target lesion revascularisation, at 1 year: the composite of cardiac death, target-vessel myocardial infarction, and clinically indicated targetlesion revascularisation occurred in 16 (5%) patients in the Absorb group vs five (3%) patients in the Xience group (difference 1·80%, 95% CI –2·48 to 5·16); and 1-year probable or definite stent thrombosis was recorded in three (0·9%) patients versus no patients (0·91%, –1·45 to 2·65). The authors conclude that the “everolimuseluting bioresorbable scaffold showed similar 1-year composite secondary clinical outcomes to the everolimuseluting metallic stent”, but this conclusion is probably an overstatement because the study was not powered to test non-inferiority of clinical adverse events. To focus on stent thrombosis, the findings show a small numerical difference against the bioresorbable scaffold (three cases vs no cases in the metallic stent group). Because stent thrombosis is a catastrophic complication that results in death and myocardial infarction in most cases, and the study enrolled so-called simple lesions of an average length of 20 mm, a difference of 0·91% might represent a genuine clinically worrisome signal. The reliable detection of a statistically meaningful difference, however, would need a much larger sample size, far larger than the 2250 patients enrolled in the
ongoing US ABSORB III trial (NCT01751906). Findings from registry studies of bioresorbable stents (dealing with patients and lesions of greater complexity, including ST-segment myocardial infarction, very long lesions, and bifurcations) have shown high rates of stent thrombosis at 6–12 months (3·0%,6 2·1%,7 2·2%,8 2·5%,9 and 2·7%10). These percentages seem to be much higher than the 1-year rates of stent thrombosis reported for secondgeneration drug-eluting stents in a network metaanalysis of more than 25 000 patients, including patients in all-comers trials.11 Bioresorbable scaffolds have been introduced to reduce and possibly eliminate late stent thrombosis, by avoiding the presence of a permanent metallic foreign body. An explanation for the apparent excess of thrombosis events in patients with bioresorbable stents in ABSORB II might come from the different postprocedural quantitive angiography and intravascular ultrasound results reported for the two stent treatments. Final in-stent minimum lumen diameter and intravascular ultrasound minimum lumen cross-sectional area were significantly smaller in the Absorb group than in the Xience group. The average minimum area of 4·89 mm² for the bioresorbable scaffold (compared with 5·73 mm² for the metallic stent) is close to or lower than the cutoff measurements suggested by many intravascular ultrasound studies as predictive of drug-eluting stent failure (thrombosis and restenosis).12,13 The investigators did not use Rotablator, cutting balloon, or high-pressure 1:1 balloon-to-artery ratio dilatation for lesion preparation; postdilatation was discouraged, resulting in a low final deployment pressure (14·23 atm for the bioresorbable scaffold vs 15·03 atm for the metallic stent, p=0·01) and intravascular ultrasound was purely documentary. Similarly, in registry studies of bioresorbable scaffolds (with rates of stent thrombosis of 2–3%) postdilatation was used in about half of cases, with final dilatation pressures of less than 15 atm and rare use of intravascular imaging guidance.6–8 Findings from other real-world studies14–16 actively using intravascular imaging and high-pressure postdilatation have not shown any stent thrombosis, suggesting that the implantation technique rather than the scaffold itself is to blame. Non-inferiority for rare adverse events is very difficult to show, and is certainly not a powerful
www.thelancet.com Published online September 14, 2014 http://dx.doi.org/10.1016/S0140-6736(14)61636-6
Published Online September 14, 2014 http://dx.doi.org/10.1016/ S0140-6736(14)61636-6 See Online/Articles http://dx.doi.org/10.1016/ S0140-6736(14)61455-0
1
Comment
motivation to switch to a bioresorbable scaffold from a well tested, less expensive, gold-standard treatment. Serruys and colleagues5 must be commended for a careful assessment of residual or recurrent angina, studied with the well-validated Seattle questionnaire and with an exercise test on a treadmill or bicycle. The perfect superimposition of results at 1 year offers convincing objective evidence of a similar symptomatic improvement, a logical outcome if ischaemia is expected to be determined by the lumen area achieved rather than the type of stent used. The presence of a statistically significant difference in a post-hoc analysis of angina episodes after discharge (16% in the bioresorbable scaffold group vs 26% in the metallic stent group, p=0·01)—reported by investigators aware of treatment allocation—is much weaker evidence than exercise duration, ECG changes, symptoms developing during maximum exercise, or A
B
D
C
C
D
B
E
F
G I
H
H
I
G
J
*Carlo Di Mario, Gianluca Caiazzo
Figure: Late in-scaffold thrombosis Top panel shows late (6 months) in-scaffold thrombosis with angiographic evidence of total occlusion of the left anterior descending artery (A).Optical coherence tomography performed after thrombectomy showed a large distal reference segment (B), clear under-expansion of the bioresorbable scaffold (area= 1·73 mm²) in the mid-segment (C) where a previously implanted stent is visible, and a well-expanded bioresorbable scaffold in the proximal segment (D). The longitudinal view emphasises the localisation of the various cross-sections (E). Bottom panel shows angiographic final result after additional high-pressure dilatation to 38 atm with a 3·0 mm non-compliant balloon and prolonged drug-eluting balloon dilatation (F). Optical coherence tomography showed an unchanged distal vessel (distal reference, G), a larger minimum cross-sectional area in the mid-segment (H) and a minimally larger proximal segment (I).The longitudinal view emphasises the uniform dilatation of the scaffolded mid-segment (J).
2
results of a questionnaire completed by patients still masked to treatment allocation. Internists and particularly cardiologists are spoilt by the availability of large outcome trials guiding them in their decisions. If a new implantable biodegradable instrument delivered the same 1-year results as a conventional metallic hip prosthesis, potentially sparing the risks of the persistence of a large permanent foreign body, what evidence would orthopaedic surgeons (and their patients) require to persuade them to switch to the new technique? Perhaps now cardiologists need to understand that the small incremental benefits of new interventional devices cannot be confirmed by conventional large outcome trials; sometimes decisions must be taken without the comfort of statistical significance. For biodegradable stents, the concerns raised by the possible increase in stent thrombosis need to be dispelled by data from sufficiently large observational studies, confirming that bioresorbable scaffolds can deliver the same results as secondgeneration drug eluting stents with the appropriate implantation technique. Pioneers carefully following up their patients, clinically and with repeated imaging, have provided compelling evidence that favourable remodelling and restoration of vasomotion is obtained after 2–5 years.4,17 Still, a larger body of long-term data is needed, and the regulatory approval process in this initial phase should impose long-term surveillance and a consent process for patients that clarifies the experimental nature of bioresorbable scaffolds. Prudence and careful monitoring are essential in the adoption of a potentially revolutionary technique. However, we cannot halt the progress of interventional cardiology while waiting for unattainable megatrials.
Cardiovascular National Institute of Health Research Biomedical Research Unit, Royal Brompton & Harefield NHS Foundation Trust, London SW3 6NP, UK (CDM, GC); and Division of Cardiology, Department of Medical and Surgical Sciences, “Magna Graecia” University, Catanzaro, Italy (GC) [email protected] CDM has received research funding from Abbott Vascular via his institution. GC declares no competing interests. 1
2
Erbel R, Di Mario C, Bartunek J, et al. Temporary scaffolding of coronary arteries with bioabsorbable magnesium stents: a prospective, nonrandomised multicentre trial. Lancet 2007; 369: 1869–75. Haude M, Erbel R, Erne P, et al. Safety and performance of the drug-eluting absorbable metal scaffold (DREAMS) in patients with de-novo coronary lesions: 12 month results of the prospective, multicentre, first-in-man BIOSOLVE-I trial. Lancet 2013; 381: 836–44.
www.thelancet.com Published online September 14, 2014 http://dx.doi.org/10.1016/S0140-6736(14)61636-6
Comment
3
4
5
6
7
8 9
10
Ormiston JA, Serruys PW, Regar E, et al. A bioabsorbable everolimus-eluting coronary stent system for patients with single de-novo coronary artery lesions (ABSORB): a prospective open-label trial. Lancet 2008; 371: 899–907. Serruys PW, Ormiston JA, Onuma Y, et al. A bioabsorbable everolimuseluting coronary stent system (ABSORB): 2-year outcomes and results from multiple imaging methods. Lancet 2009; 373: 897–910. Serruys PW, Chevalier B, Dudek D, et al. A bioresorbable everolimus-eluting scaffold versus a metallic everolimus-eluting stent for ischaemic heart disease caused by de-novo native coronary artery lesions (ABSORB II): an interim 1-year analysis of clinical and procedural secondary outcomes from a randomised controlled trial. Lancet 2014; published online Sept 14. http://dx.doi.org/10.1016/S0140-6736(14)61455-0. Kraak RP, Hassell ME, Grundeken MJ, et al. Initial experience and clinical evaluation of the Absorb bioresorbable vascular scaffold (BVS) in real-world practice: the AMC Single Centre Real World PCI Registry. EuroIntervention 2014; published online Aug 20. DOI:10.4244/ EIJY14M08_08. Capodanno D, Gori T, Nef H, et al. Percutaneous coronary intervention with everolimus-eluting bioresorbable vascular scaffolds in routine clinical practice: early and midterm outcomes from the European multicentre GHOST-EU registry. EuroIntervention 2014; published online July 18. DOI:10.4244/EIJY14M07_11. van Geuns RJ. EuroPCR2014. http://www.pcronline.com/Lectures/2014/ BVS-Expand-6-month-results (accessed Sept 8, 2014). Kočka V, Malý M, Toušek P, et al. Bioresorbable vascular scaffolds in acute ST-segment elevation myocardial infarction: a prospective multicentre study ’Prague 19’. Eur Heart J 2014; 35: 787–94. Gori T, Schulz E, Hink U, et al. Early outcome after implantation of Absorb bioresorbable drug-eluting scaffolds in patients with acute coronary syndromes. EuroIntervention 2014; 9: 1036–41.
11
12
13
14
15
16
17
Kang SH, Park KW, Kang DY, et al. Biodegradable-polymer drug-eluting stents vs. bare metal stents vs. durable-polymer drug-eluting stents: a systematic review and Bayesian approach network meta-analysis. Eur Heart J 2014; 35: 1147–58. Fujii K, Carlier SG, Mintz GS, et al. Stent underexpansion and residual reference segment stenosis are related to stent thrombosis after sirolimuseluting stent implantation: an intravascular ultrasound study. J Am Coll Cardiol 2005; 45: 995–98. Doi H, Maehara A, Mintz GS, et al. Impact of post-intervention minimal stent area on 9-month follow-up patency of paclitaxel-eluting stents: an integrated intravascular ultrasound analysis from the TAXUS IV, V, and VI and TAXUS ATLAS Workhorse, Long Lesion, and Direct Stent Trials. JACC Cardiovasc Interv 2009; 2: 1269–75. Mattesini A, Secco GG, Dall’Ara G, et al. ABSORB biodegradable stents versus second-generation metal stents: a comparison study of 100 complex lesions treated under OCT guidance. JACC Cardiovasc Interv 2014; 7: 741–50. Brown AJ, McCormick LM, Braganza DM, Bennett MR, Hoole SP, West NE. Expansion and malapposition characteristics after bioresorbable vascular scaffold implantation. Catheter Cardiovasc Interv 2014; 84: 37–45. Costopoulos C, Latib A, Naganuma T, et al. Comparison of early clinical outcomes between absorb bioresorbable vascular scaffold and everolimuseluting stent implantation in a real-world population. Catheter Cardiovasc Interv 2014; published online June 6. DOI:10.1002/ ccd.25569. Onuma Y, Dudek D, Thuesen L, et al. Five-year clinical and functional multislice computed tomography angiographic results after coronary implantation of the fully resorbable polymeric everolimus-eluting scaffold in patients with de novo coronary artery disease: the ABSORB cohort A trial. JACC Cardiovasc Interv 2013; 6: 999–1009.
www.thelancet.com Published online September 14, 2014 http://dx.doi.org/10.1016/S0140-6736(14)61636-6
3
