- Email: [email protected]
“Virtual” in-vivo bench test for bifurcation stenting with “StentBoost”
International Journal of Cardiology 133 (2009) e67 – e69 www.elsevier.com/locate/ijcard
Letter to the Editor
“Virtual” in-vivo bench test for bifurcation stenting with “StentBoost” Pierfrancesco Agostoni ⁎, Stefan Verheye, Paul Vermeersch, Kristoff Cornelis, Glenn Van Langenhove Antwerp Cardiovascular Institute Middelheim, AZ Middelheim, Lindendreef 1, 2020 Antwerp, Belgium Received 28 August 2007; accepted 17 November 2007 Available online 21 February 2008
Abstract “StentBoost” is a new angiographic technique that allows improved angiographic visualization of stents deployed in coronary arteries, by enhancing the X-ray focus of the region where the stent is placed. Using this technique we were able to assess the deformation and the expansion of a stent deployed to treat a bifurcation lesion between the mid-left anterior descending (LAD) artery and a big second diagonal branch, during sequential inflations of: (1) the stent per se in the LAD, (2) the ostium of the diagonal branch through the stent struts, (3) the stent again with a non compliant balloon, and (4) both branches with the kissing balloon technique. “StentBoost” guided our clinical and angiographic decision-making process and allowed us to create a “virtual” bench test of the stent deployed at the level of the bifurcation treated. © 2007 Elsevier Ireland Ltd. All rights reserved. Keywords: Stent; Bifurcation lesion; Angiography
A 76 year-old woman with known hypercholesterolemia and arterial hypertension underwent a diagnostic coronary angiogram because of effort-induced dyspnea and repetitive syncopal episodes with an inconclusive sub-maximal bicycle stress test. The angiogram revealed single vessel disease with a significant bifurcation lesion (Medina classification type 010) [1] involving the mid-left anterior descendens (LAD) artery and an important second diagonal branch (Fig. 1A). The patient was pretreated for 1 week with acetylsalicylic acid (100 mg/day) and clopidogrel (75 mg/day) and a percutaneous coronary intervention was planned. After full anticoagulation with weight-adjusted unfractionated heparin, both branches of the bifurcation lesion were wired. Due to the lack of angiographically evident disease at the ostium of the diagonal, direct stenting (3.0 × 16 mm bare metal stent expanded at 14 atm) of the LAD was performed, positioning the stent over the origin of the diagonal (Fig. 1B). A control angiogram revealed some under-expansion in the proximal and mid part of the stent and a severe stenosis of the ostium ⁎ Corresponding author. Tel.: +32 3 2803255; fax: +32 3 2803225. E-mail address: [email protected] (P. Agostoni). 0167-5273/$ - see front matter © 2007 Elsevier Ireland Ltd. All rights reserved. doi:10.1016/j.ijcard.2007.11.018
of the diagonal, due to plaque shift (Fig. 1C). After rewiring the diagonal through the stent struts, additional balloon dilatations of both branches were planned. A single inflation with a 2.5 × 10 mm balloon up to 16 atm was performed at the ostium of the diagonal (Fig. 1D). A second inflation was performed in the LAD inside the stent boundaries with a 3.0 × 10 non compliant balloon up to 20 atm (Fig. 1E). A final kissing balloon dilatation was additionally performed with the same balloons used before, both inflated at 16 atm (Fig. 1F). The final angiogram showed an optimal angiographic result in both branches (Fig. 1G). “StentBoost” (Philips Medical Systems Nederland BV, Best, The Netherlands), a new technique that allows improved angiographic visualization of the stent, by enhancing the X-ray focus of the region where the stent is placed [2,3], was determinant to understand the deformation of the stent after each inflation and to guide the correct expansion of the stent. “StentBoost” images are generated as follows. With the balloon markers located within the stented segment, a 3 seconds digital cineangiogram of the stented region is acquired without injection of contrast. The image sequence is automatically transferred to an interventional workstation that is part of the X-ray
e68
P. Agostoni et al. / International Journal of Cardiology 133 (2009) e67–e69
Fig. 1. (A) Coronary angiogram (right anterior oblique cranial view) showing a significant bifurcation lesion (Medina type 010) involving the mid-left anterior descendens artery and an important second diagonal branch. (B) Stent positioning in the left anterior descending over the ostium of the diagonal branch, and (C) angiographic result after stent deployment, revealing some under-expansion in the proximal and mid part of the stent and a severe stenosis of the ostium of the diagonal, most probably due to plaque shift. (D) Balloon (2.5 × 10 mm at 16 atm) dilatation of the ostium of the diagonal branch, (E) non compliant balloon (3.0 × 10 mm at 20 atm) postdilatation of the stent, and (F) final kissing balloon inflation (both balloons at 16 atm). (G) Final angiographic result of the procedure, in the right anterior oblique cranial view.
Fig. 2. Sequential analysis of the stenting procedure: with “StentBoost” (top: A–D), and with normal angiography (bottom: A'–D'). (A) After stent deployment, the stent had a tubular appearance and no scaffolding of the ostium of the diagonal was evident, (B) after dilatation of the ostium of the diagonal, improved opening of the stent struts directed toward the diagonal branch was evident, however severe deformation of the stent in the left anterior descending just after the ostium of the diagonal was clear, (C) after post-dilatation in the stent with non compliant balloon, a better expansion of the whole stent was obtained with also some residual scaffolding of the ostium of the diagonal branch, (D) after final kissing balloon, optimal expansion of the stent in the left anterior descending and optimal opening of the struts directly related to the ostium of the diagonal branch were visible. Steps A'–D' recorded with normal angiographic images correspond to steps A–D reported before with “StentBoost”: with the normal angiographic acquisition, the lack of clear assessment of stent expansion and deformation is evident.
P. Agostoni et al. / International Journal of Cardiology 133 (2009) e67–e69
e69
Fig. 3. “StentBoost Subtract” enhanced sequence of the stented bifurcation in the right anterior oblique cranial view.
system. Here, the software package averages the selected frames, correcting for motion by using the balloon markers as a spatial reference point to align each frame in the series. This creates an enhanced image of the stent with an improved signal-to-noise ratio, which is immediately visible in the exam room. Applying this technique to the described case, a “virtual” in-vivo bench test of the deployed stent was possible. After stent deployment, “StentBoost” revealed that the stent had a tubular appearance and no scaffolding of the ostium of the diagonal was evident (Fig. 2A). After dilatation of the ostium of the diagonal, improved opening of the stent struts directed toward the diagonal branch was evident, however severe deformation of the stent in the LAD just after the ostium of the diagonal was clear (Fig. 2B). After LAD dilatation, a better expansion of the whole stent was obtained with also some residual scaffolding of the ostium of the diagonal branch (Fig. 2C). After final kissing balloon, optimal expansion of the stent in the LAD and optimal opening of the struts directly related to the ostium of the diagonal branch were visible (Fig. 2D). Normal angiographic acquisitions of the stent after each inflation would have not allowed the same precise assessment of stent expansion and deformation (Fig. 2A'–D'). To further assess the quality of the result, “StentBoost Subtract” was used [4]. This is a recently developed X-ray enhancing technique, based on the previously described “StentBoost”, that allows an improved visualization of the
stent in relation to the corresponding vessel lumen. To perform “StentBoost Subtract”, a single cine run is acquired, starting with around 3 s without contrast, followed by additional 3 s of contrast injection. By superimposing motion compensated image frames of the moving stent, a high-quality image of a deployed stent is generated. The application automatically matches the stent image with an image of the corresponding vessel lumen. The result is instantaneously visible in the exam room, without any user interaction. As evident from the images, “StentBoost Subtract” enabled an improved visualization of the good expansion of the stent and of its apposition to the vessel wall, clearly revealing also a calcified plaque in the LAD on the opposite site in respect to the origin of the diagonal branch (Fig. 3). References [1] Medina A, Suárez de Lezo J, Pan M. A new classification of coronary bifurcation lesions. Rev Esp Cardiol 2006;59:183. [2] Vydt T, Van Langenhove G. Facilitated recognition of an undeployed stent with StentBoost. Int J Cardiol 2006;112:397–8. [3] Mishell JM, Vakharia KT, Ports TA, Yeghiazarians Y, Michaels AD. Determination of adequate coronary stent expansion using StentBoost, a novel fluoroscopic image processing technique. Catheter Cardiovasc Interv 2006;69:84–93. [4] Agostoni P, Verheye S. Bifurcation stenting with a dedicated biolimuseluting stent: X-ray visual enhancement of the final angiographic result with “StentBoost Subtract”. Catheter Cardiovasc Interv 2007;70:233–6.
Letter to the Editor
“Virtual” in-vivo bench test for bifurcation stenting with “StentBoost” Pierfrancesco Agostoni ⁎, Stefan Verheye, Paul Vermeersch, Kristoff Cornelis, Glenn Van Langenhove Antwerp Cardiovascular Institute Middelheim, AZ Middelheim, Lindendreef 1, 2020 Antwerp, Belgium Received 28 August 2007; accepted 17 November 2007 Available online 21 February 2008
Abstract “StentBoost” is a new angiographic technique that allows improved angiographic visualization of stents deployed in coronary arteries, by enhancing the X-ray focus of the region where the stent is placed. Using this technique we were able to assess the deformation and the expansion of a stent deployed to treat a bifurcation lesion between the mid-left anterior descending (LAD) artery and a big second diagonal branch, during sequential inflations of: (1) the stent per se in the LAD, (2) the ostium of the diagonal branch through the stent struts, (3) the stent again with a non compliant balloon, and (4) both branches with the kissing balloon technique. “StentBoost” guided our clinical and angiographic decision-making process and allowed us to create a “virtual” bench test of the stent deployed at the level of the bifurcation treated. © 2007 Elsevier Ireland Ltd. All rights reserved. Keywords: Stent; Bifurcation lesion; Angiography
A 76 year-old woman with known hypercholesterolemia and arterial hypertension underwent a diagnostic coronary angiogram because of effort-induced dyspnea and repetitive syncopal episodes with an inconclusive sub-maximal bicycle stress test. The angiogram revealed single vessel disease with a significant bifurcation lesion (Medina classification type 010) [1] involving the mid-left anterior descendens (LAD) artery and an important second diagonal branch (Fig. 1A). The patient was pretreated for 1 week with acetylsalicylic acid (100 mg/day) and clopidogrel (75 mg/day) and a percutaneous coronary intervention was planned. After full anticoagulation with weight-adjusted unfractionated heparin, both branches of the bifurcation lesion were wired. Due to the lack of angiographically evident disease at the ostium of the diagonal, direct stenting (3.0 × 16 mm bare metal stent expanded at 14 atm) of the LAD was performed, positioning the stent over the origin of the diagonal (Fig. 1B). A control angiogram revealed some under-expansion in the proximal and mid part of the stent and a severe stenosis of the ostium ⁎ Corresponding author. Tel.: +32 3 2803255; fax: +32 3 2803225. E-mail address: [email protected] (P. Agostoni). 0167-5273/$ - see front matter © 2007 Elsevier Ireland Ltd. All rights reserved. doi:10.1016/j.ijcard.2007.11.018
of the diagonal, due to plaque shift (Fig. 1C). After rewiring the diagonal through the stent struts, additional balloon dilatations of both branches were planned. A single inflation with a 2.5 × 10 mm balloon up to 16 atm was performed at the ostium of the diagonal (Fig. 1D). A second inflation was performed in the LAD inside the stent boundaries with a 3.0 × 10 non compliant balloon up to 20 atm (Fig. 1E). A final kissing balloon dilatation was additionally performed with the same balloons used before, both inflated at 16 atm (Fig. 1F). The final angiogram showed an optimal angiographic result in both branches (Fig. 1G). “StentBoost” (Philips Medical Systems Nederland BV, Best, The Netherlands), a new technique that allows improved angiographic visualization of the stent, by enhancing the X-ray focus of the region where the stent is placed [2,3], was determinant to understand the deformation of the stent after each inflation and to guide the correct expansion of the stent. “StentBoost” images are generated as follows. With the balloon markers located within the stented segment, a 3 seconds digital cineangiogram of the stented region is acquired without injection of contrast. The image sequence is automatically transferred to an interventional workstation that is part of the X-ray
e68
P. Agostoni et al. / International Journal of Cardiology 133 (2009) e67–e69
Fig. 1. (A) Coronary angiogram (right anterior oblique cranial view) showing a significant bifurcation lesion (Medina type 010) involving the mid-left anterior descendens artery and an important second diagonal branch. (B) Stent positioning in the left anterior descending over the ostium of the diagonal branch, and (C) angiographic result after stent deployment, revealing some under-expansion in the proximal and mid part of the stent and a severe stenosis of the ostium of the diagonal, most probably due to plaque shift. (D) Balloon (2.5 × 10 mm at 16 atm) dilatation of the ostium of the diagonal branch, (E) non compliant balloon (3.0 × 10 mm at 20 atm) postdilatation of the stent, and (F) final kissing balloon inflation (both balloons at 16 atm). (G) Final angiographic result of the procedure, in the right anterior oblique cranial view.
Fig. 2. Sequential analysis of the stenting procedure: with “StentBoost” (top: A–D), and with normal angiography (bottom: A'–D'). (A) After stent deployment, the stent had a tubular appearance and no scaffolding of the ostium of the diagonal was evident, (B) after dilatation of the ostium of the diagonal, improved opening of the stent struts directed toward the diagonal branch was evident, however severe deformation of the stent in the left anterior descending just after the ostium of the diagonal was clear, (C) after post-dilatation in the stent with non compliant balloon, a better expansion of the whole stent was obtained with also some residual scaffolding of the ostium of the diagonal branch, (D) after final kissing balloon, optimal expansion of the stent in the left anterior descending and optimal opening of the struts directly related to the ostium of the diagonal branch were visible. Steps A'–D' recorded with normal angiographic images correspond to steps A–D reported before with “StentBoost”: with the normal angiographic acquisition, the lack of clear assessment of stent expansion and deformation is evident.
P. Agostoni et al. / International Journal of Cardiology 133 (2009) e67–e69
e69
Fig. 3. “StentBoost Subtract” enhanced sequence of the stented bifurcation in the right anterior oblique cranial view.
system. Here, the software package averages the selected frames, correcting for motion by using the balloon markers as a spatial reference point to align each frame in the series. This creates an enhanced image of the stent with an improved signal-to-noise ratio, which is immediately visible in the exam room. Applying this technique to the described case, a “virtual” in-vivo bench test of the deployed stent was possible. After stent deployment, “StentBoost” revealed that the stent had a tubular appearance and no scaffolding of the ostium of the diagonal was evident (Fig. 2A). After dilatation of the ostium of the diagonal, improved opening of the stent struts directed toward the diagonal branch was evident, however severe deformation of the stent in the LAD just after the ostium of the diagonal was clear (Fig. 2B). After LAD dilatation, a better expansion of the whole stent was obtained with also some residual scaffolding of the ostium of the diagonal branch (Fig. 2C). After final kissing balloon, optimal expansion of the stent in the LAD and optimal opening of the struts directly related to the ostium of the diagonal branch were visible (Fig. 2D). Normal angiographic acquisitions of the stent after each inflation would have not allowed the same precise assessment of stent expansion and deformation (Fig. 2A'–D'). To further assess the quality of the result, “StentBoost Subtract” was used [4]. This is a recently developed X-ray enhancing technique, based on the previously described “StentBoost”, that allows an improved visualization of the
stent in relation to the corresponding vessel lumen. To perform “StentBoost Subtract”, a single cine run is acquired, starting with around 3 s without contrast, followed by additional 3 s of contrast injection. By superimposing motion compensated image frames of the moving stent, a high-quality image of a deployed stent is generated. The application automatically matches the stent image with an image of the corresponding vessel lumen. The result is instantaneously visible in the exam room, without any user interaction. As evident from the images, “StentBoost Subtract” enabled an improved visualization of the good expansion of the stent and of its apposition to the vessel wall, clearly revealing also a calcified plaque in the LAD on the opposite site in respect to the origin of the diagonal branch (Fig. 3). References [1] Medina A, Suárez de Lezo J, Pan M. A new classification of coronary bifurcation lesions. Rev Esp Cardiol 2006;59:183. [2] Vydt T, Van Langenhove G. Facilitated recognition of an undeployed stent with StentBoost. Int J Cardiol 2006;112:397–8. [3] Mishell JM, Vakharia KT, Ports TA, Yeghiazarians Y, Michaels AD. Determination of adequate coronary stent expansion using StentBoost, a novel fluoroscopic image processing technique. Catheter Cardiovasc Interv 2006;69:84–93. [4] Agostoni P, Verheye S. Bifurcation stenting with a dedicated biolimuseluting stent: X-ray visual enhancement of the final angiographic result with “StentBoost Subtract”. Catheter Cardiovasc Interv 2007;70:233–6.