- Email: [email protected]
Guiding Light
JACC: CARDIOVASCULAR INTERVENTIONS
VOL. 9, NO. 22, 2016
ª 2016 BY THE AMERICAN COLLEGE OF CARDIOLOGY FOUNDATION
ISSN 1936-8798/$36.00
PUBLISHED BY ELSEVIER
Letters TO THE EDITOR
results and an increase in subsequent adverse clinical events (1). Currently, there is no standardized evidence-based strategy for PCI of calcified coronary
Guiding Light
lesions. Decisions for the use of adjunctive atheroa-
Insights Into Atherectomy by
cess rates (2)—are based on visual estimation of
Optical Coherence Tomography
calcification
blation—shown to increase the acute procedural sucseverity
on
angiography
(with
its
inherent limitations [3]) or when delivery of devices is impeded by calcified deposits in the vessel wall. Coronary calcification presents multiple technical
Although the so-called “rota-regret” remains com-
challenges in percutaneous coronary intervention
mon following suboptimal acute procedural results in
(PCI) and is associated with suboptimal procedural
calcified plaques not prepared by atheroablation, the
F I G U R E 1 OCT-Guided, OA-Facilitated PCI on a Long, Diffusely Calcified, Physiologically Significant Lesion in a Patient With Stable Angina
(A) Ischemia-producing diffuse stenosis in the left anterior descending coronary artery, without discrete segment of step-up along the fractional flow reserve (FFR) pullback. (B) On optical coherence tomography (OCT), presence of superficial and deep calcification of varying morphology and severity along the length of the artery led to the decision to modify the plaques by orbital atherectomy (OA). (C and D) OA caused differential ablation of the calcium sheets along the guidewire course in the shape of a smooth luminal surface with cylindrical geometry, forming a groove that followed the guidewire course (arrows with w40% luminal gain). After balloon dilation, multiple fractures and medial dissection were observed, leading to w70% additional area gain. (E) After deployment of 2 drug-eluting stents, minimal luminal areas in proximal and distal halves of the revascularized segment were compared with their respective reference segments (due to the long lesion length and natural tapering of the vessel) and were deemed adequately expanded. (F) Final result on angiography and relief of ischemia on FFR pullback. Image analysis was performed on CAAS Intravascular (Pie Medical, Maastricht, the Netherlands). MSA ¼ minimal stent area; PCI ¼ percutaneous coronary intervention; ref ¼ reference.
JACC: CARDIOVASCULAR INTERVENTIONS VOL. 9, NO. 22, 2016
Letters to the Editor
NOVEMBER 28, 2016:2362–8
current lack of data to demonstrate improved long-
documented ischemia that may have been otherwise
term cardiovascular outcomes and an association
deemed unsuitable for PCI due to diffuse disease
with greater late lumen loss with adjunctive athe-
or bypass-grafting because of poor distal target
roablation (1) contribute to the controversy.
(Figure 1). It is important to note that pre-PCI
High-resolution intravascular imaging by optical
OCT may be technically challenging in severely
coherence tomography (OCT) has the potential to
calcified stenotic lesions due to inadequate blood
guide all steps of PCI in order to provide an inte-
clearance or failure to deliver the imaging catheter,
grated, more standardized approach in treating
necessitating
calcified lesions. These steps are illustrated in
acquisition. Specifically addressing the areas high-
Figure 1. OCT allows for accurate quantitation of the
lighted would set the scene for prospective random-
extent and severity of calcification that may aid in
ized trials to investigate OCT-guided atherectomy
clinical
of
(including efficacy of different atherectomy devices)
adjunctive atheroablation and device selection).
versus no-atherectomy approaches and their effects
Compared with intravascular ultrasound, calcifica-
on long-term clinical outcomes.
decision-making
(i.e.,
upfront
use
plaque
modification
before
image
tion depth can also be assessed in addition to circumferential arc, thus providing accurate measurement of calcification area, shown to negatively correlate with the degree of stent expansion (3). Moreover, OCT may allow for assessment of the modifying effects of atheroablation and adequacy of lesion
preparation.
Atherectomy-assisted
plaque
modification (e.g., by orbital atherectomy in Figure 1) results in modest area gain that may facilitate delivery
of
the
interventional
devices;
whereas
adjunctive balloon dilation can cause fracture and intraplaque dissections, leading to larger lumen gain (Figure 1) and improved stent expansion and more uniform stent apposition. Indeed, calcium fracture has been associated with higher stent expansion and lower in-stent restenosis and stent thrombosis (4), and we recognize it as a potentially important mechanism for optimization of PCI in calcified lesions. Calcium fracture in plaques with a combination of wide arc (to allow for the 2 edges of the calcium deposit to be pushed by balloon in order to induce fracture) and low calcium thickness (to increase fragility) on OCT (3) indicates the possibility to derive calcium fragility parameters on OCT to guide appropriate strategies for lesion preparation. Moreover, using the external elastic lamina-based
Keyvan Karimi Galougahi, MD, PhD Richard A. Shlofmitz, MD Ori Ben-Yehuda, MD Philippe Généreux, MD Akiko Maehara, MD Gary S. Mintz, MD Gregg W. Stone, MD Jeffrey W. Moses, MD *Ziad A. Ali, MD, DPhil *Center for Interventional Vascular Therapy Division of Cardiology New York Presbyterian Hospital and Columbia University New York, New York 10032 E-mail: [email protected] http://dx.doi.org/10.1016/j.jcin.2016.09.028 Please note: Dr. Shlofmitz is on the speakers bureau of Cardiovascular Systems, Inc. Dr. Ben-Yehuda received institutional research grants from St. Jude Medical. Dr. Généreux has received speakers fees from Edwards Lifesciences and Cardiovascular Systems; has been a consultant for Cardiovascular Systems; and has received research grants from Boston Scientific and Cardiovascular Systems. Dr. Maehara has received research grants from St. Jude Medical and Boston Scientific; has received speakers fees from St. Jude Medical; and has been a consultant for Boston Scientific. Dr. Mintz has received honoraria, institutional fellowship, and grant support from Boston Scientific; and has received grant support from St. Jude Medical. Dr. Ali is a consultant for and holds institutional research grants to Columbia University from Cardiovascular Systems Inc. and St. Jude Medical; and has received personal fees from Acist Medical. Cardiovascular Research Foundation receives grant support from St. Jude Medical. All other authors have reported that they have no relationships relevant to the contents of this paper to disclose.
measurements we have tested in the ILUMIEN III (ILUMIEN III: OPTIMIZE PCI) study (NCT02471586)
REFERENCES
(5), OCT allows for accurate and precise determina-
1. Madhavan MV, Tarigopula M, Mintz GS, Maehara A, Stone GW, Genereux P.
tion of vessel dimensions and thus selection of
Coronary artery calcification: pathogenesis and prognostic implications. J Am Coll Cardiol 2014;63:1703–14.
appropriate balloon and stent sizes, which may be over- or underestimated in the presence of heavy calcification on angiography. Lastly, with the angiography coregistration feature, OCT can guide stent deployment and targeted post-dilation of underexpanded segments to optimize procedural results (Figure 1). Thus,
OCT
guidance
may
optimize
PCI
on
calcified lesions, for instance, making revascularization feasible in an extensively calcified artery with
2. Tomey MI, Sharma SK. Interventional options for coronary artery calcification. Curr Cardiol Rep 2016;18:12. 3. Maejima N, Hibi K, Saka K, et al. Relationship between thickness of calcium on optical coherence tomography and crack formation after balloon dilatation in calcified plaque requiring rotational atherectomy. Circ J 2016;80:1413–9. 4. Kubo T, Shimamura K, Ino Y, et al. Superficial calcium fracture after PCI as assessed by OCT. J Am Coll Cardiol Img 2015;8:1228–9. 5. Ali ZA, Maehara A, Généreux P, et al. Optical coherence tomography compared with intravascular ultrasound and with angiography to guide coronary stent implantation (ILUMIEN III: OPTIMIZE PCI): a randomised controlled trial. The Lancet 2016 [E-pub ahead of print].
2363
VOL. 9, NO. 22, 2016
ª 2016 BY THE AMERICAN COLLEGE OF CARDIOLOGY FOUNDATION
ISSN 1936-8798/$36.00
PUBLISHED BY ELSEVIER
Letters TO THE EDITOR
results and an increase in subsequent adverse clinical events (1). Currently, there is no standardized evidence-based strategy for PCI of calcified coronary
Guiding Light
lesions. Decisions for the use of adjunctive atheroa-
Insights Into Atherectomy by
cess rates (2)—are based on visual estimation of
Optical Coherence Tomography
calcification
blation—shown to increase the acute procedural sucseverity
on
angiography
(with
its
inherent limitations [3]) or when delivery of devices is impeded by calcified deposits in the vessel wall. Coronary calcification presents multiple technical
Although the so-called “rota-regret” remains com-
challenges in percutaneous coronary intervention
mon following suboptimal acute procedural results in
(PCI) and is associated with suboptimal procedural
calcified plaques not prepared by atheroablation, the
F I G U R E 1 OCT-Guided, OA-Facilitated PCI on a Long, Diffusely Calcified, Physiologically Significant Lesion in a Patient With Stable Angina
(A) Ischemia-producing diffuse stenosis in the left anterior descending coronary artery, without discrete segment of step-up along the fractional flow reserve (FFR) pullback. (B) On optical coherence tomography (OCT), presence of superficial and deep calcification of varying morphology and severity along the length of the artery led to the decision to modify the plaques by orbital atherectomy (OA). (C and D) OA caused differential ablation of the calcium sheets along the guidewire course in the shape of a smooth luminal surface with cylindrical geometry, forming a groove that followed the guidewire course (arrows with w40% luminal gain). After balloon dilation, multiple fractures and medial dissection were observed, leading to w70% additional area gain. (E) After deployment of 2 drug-eluting stents, minimal luminal areas in proximal and distal halves of the revascularized segment were compared with their respective reference segments (due to the long lesion length and natural tapering of the vessel) and were deemed adequately expanded. (F) Final result on angiography and relief of ischemia on FFR pullback. Image analysis was performed on CAAS Intravascular (Pie Medical, Maastricht, the Netherlands). MSA ¼ minimal stent area; PCI ¼ percutaneous coronary intervention; ref ¼ reference.
JACC: CARDIOVASCULAR INTERVENTIONS VOL. 9, NO. 22, 2016
Letters to the Editor
NOVEMBER 28, 2016:2362–8
current lack of data to demonstrate improved long-
documented ischemia that may have been otherwise
term cardiovascular outcomes and an association
deemed unsuitable for PCI due to diffuse disease
with greater late lumen loss with adjunctive athe-
or bypass-grafting because of poor distal target
roablation (1) contribute to the controversy.
(Figure 1). It is important to note that pre-PCI
High-resolution intravascular imaging by optical
OCT may be technically challenging in severely
coherence tomography (OCT) has the potential to
calcified stenotic lesions due to inadequate blood
guide all steps of PCI in order to provide an inte-
clearance or failure to deliver the imaging catheter,
grated, more standardized approach in treating
necessitating
calcified lesions. These steps are illustrated in
acquisition. Specifically addressing the areas high-
Figure 1. OCT allows for accurate quantitation of the
lighted would set the scene for prospective random-
extent and severity of calcification that may aid in
ized trials to investigate OCT-guided atherectomy
clinical
of
(including efficacy of different atherectomy devices)
adjunctive atheroablation and device selection).
versus no-atherectomy approaches and their effects
Compared with intravascular ultrasound, calcifica-
on long-term clinical outcomes.
decision-making
(i.e.,
upfront
use
plaque
modification
before
image
tion depth can also be assessed in addition to circumferential arc, thus providing accurate measurement of calcification area, shown to negatively correlate with the degree of stent expansion (3). Moreover, OCT may allow for assessment of the modifying effects of atheroablation and adequacy of lesion
preparation.
Atherectomy-assisted
plaque
modification (e.g., by orbital atherectomy in Figure 1) results in modest area gain that may facilitate delivery
of
the
interventional
devices;
whereas
adjunctive balloon dilation can cause fracture and intraplaque dissections, leading to larger lumen gain (Figure 1) and improved stent expansion and more uniform stent apposition. Indeed, calcium fracture has been associated with higher stent expansion and lower in-stent restenosis and stent thrombosis (4), and we recognize it as a potentially important mechanism for optimization of PCI in calcified lesions. Calcium fracture in plaques with a combination of wide arc (to allow for the 2 edges of the calcium deposit to be pushed by balloon in order to induce fracture) and low calcium thickness (to increase fragility) on OCT (3) indicates the possibility to derive calcium fragility parameters on OCT to guide appropriate strategies for lesion preparation. Moreover, using the external elastic lamina-based
Keyvan Karimi Galougahi, MD, PhD Richard A. Shlofmitz, MD Ori Ben-Yehuda, MD Philippe Généreux, MD Akiko Maehara, MD Gary S. Mintz, MD Gregg W. Stone, MD Jeffrey W. Moses, MD *Ziad A. Ali, MD, DPhil *Center for Interventional Vascular Therapy Division of Cardiology New York Presbyterian Hospital and Columbia University New York, New York 10032 E-mail: [email protected] http://dx.doi.org/10.1016/j.jcin.2016.09.028 Please note: Dr. Shlofmitz is on the speakers bureau of Cardiovascular Systems, Inc. Dr. Ben-Yehuda received institutional research grants from St. Jude Medical. Dr. Généreux has received speakers fees from Edwards Lifesciences and Cardiovascular Systems; has been a consultant for Cardiovascular Systems; and has received research grants from Boston Scientific and Cardiovascular Systems. Dr. Maehara has received research grants from St. Jude Medical and Boston Scientific; has received speakers fees from St. Jude Medical; and has been a consultant for Boston Scientific. Dr. Mintz has received honoraria, institutional fellowship, and grant support from Boston Scientific; and has received grant support from St. Jude Medical. Dr. Ali is a consultant for and holds institutional research grants to Columbia University from Cardiovascular Systems Inc. and St. Jude Medical; and has received personal fees from Acist Medical. Cardiovascular Research Foundation receives grant support from St. Jude Medical. All other authors have reported that they have no relationships relevant to the contents of this paper to disclose.
measurements we have tested in the ILUMIEN III (ILUMIEN III: OPTIMIZE PCI) study (NCT02471586)
REFERENCES
(5), OCT allows for accurate and precise determina-
1. Madhavan MV, Tarigopula M, Mintz GS, Maehara A, Stone GW, Genereux P.
tion of vessel dimensions and thus selection of
Coronary artery calcification: pathogenesis and prognostic implications. J Am Coll Cardiol 2014;63:1703–14.
appropriate balloon and stent sizes, which may be over- or underestimated in the presence of heavy calcification on angiography. Lastly, with the angiography coregistration feature, OCT can guide stent deployment and targeted post-dilation of underexpanded segments to optimize procedural results (Figure 1). Thus,
OCT
guidance
may
optimize
PCI
on
calcified lesions, for instance, making revascularization feasible in an extensively calcified artery with
2. Tomey MI, Sharma SK. Interventional options for coronary artery calcification. Curr Cardiol Rep 2016;18:12. 3. Maejima N, Hibi K, Saka K, et al. Relationship between thickness of calcium on optical coherence tomography and crack formation after balloon dilatation in calcified plaque requiring rotational atherectomy. Circ J 2016;80:1413–9. 4. Kubo T, Shimamura K, Ino Y, et al. Superficial calcium fracture after PCI as assessed by OCT. J Am Coll Cardiol Img 2015;8:1228–9. 5. Ali ZA, Maehara A, Généreux P, et al. Optical coherence tomography compared with intravascular ultrasound and with angiography to guide coronary stent implantation (ILUMIEN III: OPTIMIZE PCI): a randomised controlled trial. The Lancet 2016 [E-pub ahead of print].
2363