Cardiovasc Interv and Ther DOI 10.1007/s12928-014-0303-3
CASE REPORT
Stent implantation and optical frequency domain imaging with carbon dioxide for chronic total occlusion in the superficial femoral artery Akihiro Nakamura • Kazuki Noda • Sota Nakajima • Hideaki Endo • Tohru Takahashi Eiji Nozaki
•
Received: 29 August 2014 / Accepted: 6 October 2014 Ó Japanese Association of Cardiovascular Intervention and Therapeutics 2014
Abstract A 68-year-old female was presented with claudication in the left lower leg. She underwent angiography with carbon dioxide (CO2) because she had a history of anaphylactic shock to iodinated contrast medium. It revealed total occlusion of the left superficial femoral artery (SFA), and subsequently endovascular therapy (EVT) was performed by an antegrade approach from the left common femoral artery. After stent implantation, we performed optical frequency domain imaging (OFDI) using CO2 as contrast medium. OFDI has been extensively studied in the coronary circulation; however, its use in the peripheral arterial circulation is scarce. We present a case of stent implantation and OFDI using CO2 as an ancillary tool during EVT for SFA lesions in the patient with contraindication to iodinated contrast medium.
system. Its system is similar to that of intravascular ultrasound (IVUS) and provides a 10-fold higher resolution as compared to IVUS. Although OFDI has now become available in the coronary intervention in Japan, its use has limited in the setting of infrainguinal peripheral artery disease (PAD). The following report is a case of patient with anaphylactic shock to iodinated contrast medium who underwent endovascular therapy (EVT) using CO2 for a total occlusion lesion in the left superficial femoral artery (SFA). In this case, we had a unique opportunity for OFDI imaging using CO2 before and after stent implantation in SFA lesions which cannot be performed in coronary imaging.
Case presentation Keywords Carbon dioxide Stenting Superficial femoral artery Optical frequency domain imaging
Introduction The use of iodinated contrast medium is limited or contraindicated in patients with impaired renal function or a history of anaphylactic shock induced by this agent. In such patients, carbon dioxide (CO2) is available as medium for digital subtraction angiography. Intravascular optical frequency domain imaging (OFDI) is a new imaging modality based on near-infrared light projected via a catheter-based
A. Nakamura (&) K. Noda S. Nakajima H. Endo T. Takahashi E. Nozaki Department of Cardiology, Iwate Prefectural Central Hospital, 1-4-1 Ueda, Morioka, Iwate 020-0096, Japan e-mail: [email protected]
In April 2013, a 68-year-old female patient who presented a clinical medical history of hypertension, diabetes mellitus, smoking, dyslipidemia was referred to our hospital for a 3-month history of intermittent claudication (Fontain classification: IIb) in her left leg. The patient had a surgical history of femoropopliteal prosthetic bypass graft in both legs for total occlusion of the superficial femoral artery (SFA) 9 years previously (Fig. 1). The patient underwent CT angiography with iodinated contrast medium. Soon after the injection of the contrast medium, she went into anaphylactic shock on the CT table. Luckily, the patient was rapidly resuscitated and suffered no permanent harm. Since this accident, the administration of iodinated contrast medium has been considered an absolute contraindication for this patient. In spite of optimal medication for 1 year, the patient showed the progressive symptom in left leg, and the maximum walking distance was about 10–20 m. The
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A. Nakamura et al.
Fig. 1 Contrast-enhanced CT angiopraphic image of femoropopliteal prosthetic bypass graft and total occlusion of SFA in left leg. CT computed tomography, SFA superficial femoral artery
ankle–brachial index (ABI) at rest was 0.41 for the left leg with monophasic wave forms. We decided to perform interventional procedure to the left SFA. In June 2014, EVT without iodinated contrast medium was performed by a crossover technique from the contralateral side. A 6-Fr 45 cm Destination peripheral guiding sheath (Terumo Medical Corp., Tokyo, Japan) was inserted in retrograde fashion into the left common femoral artery (CFA) after the successful right CFA puncture. Angiography was performed by injection of CO2 from the sheath, and it revealed total occlusion in the SFA mid portion with collaterals supplying the distal portion of the SFA (Fig. 2A). A 0.018-inch ATHLETE Paddler HT guide wire (Japan Lifeline Co. Ltd., Tokyo, Japan) was used to cross the peripheral chronic total occlusion (CTO) lesion in the
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left SFA with conventional techniques. EVT for CTO lesion in the left SFA was performed using a 5.0 9 100 mm Senri balloon (Terumo Medical Co. Ltd., Tokyo, Japan) with several overlapping inflations. Before stent implantation, the observation by IVUS (Vision PV. 018, Volcano Co. Ltd., San Diego, CA, USA) was performed (Fig. 3). After exchanging with a 0.014-inch Spindle guide wire (St. Jude Medical, Inc., St. Paul, MN, USA), the OFDI catheter (FastView, Treumo Medical Co. Ltd., Tokyo, Japan) was advanced over this wire and the imaging core was placed distal of the total lesion of the SFA. The catheter position was confirmed by the radiopaque markers of the OFDI catheter. At this point, approximately 30 mL of CO2 was hand-injected through the sheath. The catheter was pull-backed automatically at a speed of 40 mm/s, and then OFDI images were depicted by Terumo-OFDI system (LUNAWAVE, Terumo Medical Co. Ltd., Tokyo, Japan) (Figs. 3, 4). Subsequently, stenting with 6.0 9 100 mm, 6.0 9 60 mm SMART Control stents (Cordis, Co. Ltd., Warren, NJ, USA) was performed. Postdilatation was performed with a 6.0 9 100 mm Fox SV balloon (Abbott Vascular Japan Co. Ltd., Tokyo, Japan). OFDI images of the SFA lesions before and after stenting were shown in Fig. 3 (A-2, 3: proximal portion; B-2, 3: mid portion; C-2, 3: distal portion, respectively). Figure 4 shows the representative OFDI images obtained during the EVT procedure. A sufficient stent area was obtained by OFDI using CO2 estimation, and final angiogram using CO2 showed good vessel patency after balloon post-dilatation (Fig. 2B). Thus, EVT procedure using CO2 was carried out without any minor or major events or complications. The X-ray fluoroscopic time was 37.4 min. The patient was discharged 2 days after the EVT procedure. At 1 month after procedure, she was completely free from quality of life-threatening claudication and ABI at rest of the left leg improved from 0.41 to 0.80.
Discussion This is the report of angiography and subsequent stent implantation using CO2 in a patient with a history of anaphylactic shock to iodinated contrast medium. Using CO2, we could also obtain OFDI imaging before and after stent implantation in the SFA lesions. To our knowledge, this is the first reported case using CO2 for OFDI imaging of the SFA lesions. Images by intra-arterial injection of CO2 are made by the replacement of the blood volume, whereas those by iodinated contrast medium are made by the mixture with the blood [1]. Although the images made by CO2 alone are
CO2 angioplasty and OFDI for SFA-CTO Fig. 2 CO2 angiography before and after EVT. A Initial CO2 angiography revealed total occlusion in the left SFA from the mid to the distal portion (a dotted line). B Final CO2 angiography after EVT procedure revealed well-dilated left SFA implanted with two stents. CO2 carbon dioxide, EVT endovascular therapy, SFA superficial femoral artery
not necessarily sufficient to visualize, much progress has been made in the quality of the images by digital subtraction angiography (DSA) and it has enabled us the diagnostic angiography in PAD patients with contraindication to iodinated contrast medium like our case [2]. Futhermore, the images by CO2 DSA have enabled us to perform EVT, especially in iliac and infrainguinal peripheral artery. Kawasaki et al. [3] showed the feasibility, safety and imaging quality of CO2 angiography in EVT for patients with chronic kidney disease as compared with the angiography with iodinated contrast medium. Higashimori et al. [4] recently reported an EVT case of iliac artery lesions in a patient with impaired renal function, and they performed stent implantation in the iliac artery using IVUS and CO2 angiography without iodinated contrast medium. Thus, it has been shown that EVT using CO2 is safe and efficient for high-risk patients with iliofemoral artery disease. In fact, we did not recognize any complication related to air contamination or embolism, and the patient did not complain of lower leg pain during CO2 injection in our case.
OFDI is a Fourier-domain optical coherence tomography (OCT) using swept optical source, and it has been introduced as a new-generation light-based imaging modality [5]. OFDI provides high-speed image acquisition and high-quality image resolution (a 10-fold higher resolution as compared to IVUS) [6], with resulting more detailed depiction and accurate quantitative assessment of intraluminal structures when compared with angiography and IVUS. Terumo-OFDI system can provide images at 158 frames/s with a total of 512 radial scans per circular cross-sectional image and had an axial resolution of \20 lm and a lateral resolution of 30 lm (at 2.5 mm) [7]. Although this modality has now become available in the coronary intervention, it has a limited use in the setting of infrainguinal peripheral artery disease. The hope is for it to be used both before and after EVT to optimize treatment choices and ensure stent wall apposition, but to date, it has only been used on a limited basis. High-quality resolution capabilities of this modality could help before and after EVT to predict outcomes or identify position errors in stent deployment; however, it has one specific limitation,
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A. Nakamura et al.
Post-Stenting
Pre-Stenting IVUS
CO2-OFDI
B-1
B-3
B-2
1mm
1mm
C-2
C-1
2mm
1mm
1mm
2mm
A-3
A-2
A-1
2mm
CO2-OFDI
1mm
C-3
1mm
Fig. 3 IVUS and OFDI images before and after stenting. A–C Show the proximal, mid, and distal portion levels in the SFA lesions, respectively. 1–3 Show the IVUS images before stenting, OFDI
images before stenting, and OFDI images after stenting, respectively. IVUS intravascular ultrasound, OFDI optical frequency domain imaging, SFA superficial femoral artery
namely, image signals are attenuated by erythrocytes. To overcome this hurdle, other medium such as contrast medium, saline, or dextran needs to be injected in the vessel during acquisition of images. In peripheral circulation, CO2 can be also used as an alternative agent that is contraindicated in coronary circulation. This allowed us a unique opportunity for application of CO2 in the field of peripheral EVT that cannot be performed in coronary interventions. Thus, in our case, CO2 was used not only as contrast media in angiography and EVT for SFA, but also as alternative agent instead of iodinated contrast medium in OFDI imaging. In the field of peripheral EVT, information regarding the images of the vessel, particularly on that of inner side, is rather scanty. As shown in Figs. 3 and 4, OFDI could provide us a high-resolution intravascular imaging as compared with IVUS images. Although its contribution to the clinical benefit is still unclear, the visualization in different aspect from IVUS will give us more information
for the treatment of peripheral arterial disease and will be useful in the judgement of therapeutic effect. There are some limitations in our method. First, we could not compare with OFDI images using other agents such as dextran and iodinated contrast medium. Although there has been no such report to date and we also have no date about comparison of CO2 and iodinated contrast medium, it would be interesting to investigate which agents would be better to obtain highquality OFDI images. If so, use of CO2 would be a viable option in the field of peripheral EVT apart from use in patients with contraindications to iodinated contrast medium. Second, the injection of CO2 could give comparable erythrocyte clearance and imaging quality in our case; however, it has not been well studied whether the full exchange of blood is possible by this method in any case. The possibility exists that the phenomenon such as surface tension occurs, with resulting residual blood in the vessel lumen. We need
123
CO2 angioplasty and OFDI for SFA-CTO
Fig. 4 Representative OFDI (A–F) and the corresponding IVUS images (A-1 to D-1) obtained during the EVT procedure. A Localized calcification was found at 3 o’clock. It showed low signal and low attenuation (asterisk). B Sheet-like dense calcification observed as heterogeneous image was found at 9–12 o’clock (asterisk), and an intimal flap was found at 5 o’clock (arrows). C Minor dissection
within vessel wall was observed at 9–11 o’clock (arrow heads). D Homogenous thick intima or a thrombus was found at 12–1 o’clock (Th). E Overlapping stents with good stent expansion. F Small cavity formation and uncovered stent struts (square surrounded by a dotted line). OFDI optical frequency domain imaging, IVUS intravascular ultrasound, EVT endovascular therapy
further investigation especially the experiment using a simulated model of blood vessel which may give us more important information about the clinical usefulness of OFDI using CO2.
simple homemade carbon dioxide delivery system in patients with ileofemoral artery disease. Circ J. 2012;76(7):1722–8. Higashimori A, Yokoi Y. Stent implantation for chronic total occlusion in the iliac artery using intravascular ultrasound-guided carbon dioxide angiography without iodinated contrast medium. Cardiovasc Interv Ther. 2013;28:415–8. Okumura T, Onuma Y, Garcia-Garcia HM, van Geuns RJ, Wykrzykowska JJ, Schultz C, et al. First-in-man evaluation of intravascular optical frequency domain imaging (OFDI) of Terumo: a comparison with intravascular ultrasound and quantitative coronary angiography. EuroIntervention. 2011;6:1037–45. Templin C, Meyer M, Mu¨ller MF, Djonov V, Hlushchuk R, Dimova I, et al. Coronary optical frequency domain imaging (OFDI) for in vivo evaluation of stent healing: comparison with light and electron microscopy. Eur Heart J. 2010;31(14):1792–801. Okamura T, Serruys PW, Regar E. Three-dimensional visualization of intracoronary thrombus during stent implantation using the second generation, Fourier domain optical coherence tomography. Eur Heart J. 2010;31(5):625.
4.
5. Conflict of interest
There is no conflict of interest of authors.
References 1. Kerrns SR, Hawkins IF Jr, Sabatelli FW. Current status of carbon dioxide angiography. Radiol Clin N Am. 1995;33:15–29. 2. Hawkins IF, Caridi JG. Carbon dioxide (CO2) digital subtraction angiography: 26-year experience at the University of Florida. Eur Radiol. 1998;8:391–402. 3. Kawasaki D, Fujii K, Fukunaga M, Masutani M, Nakata A, Masuyama T. Safety and efficacy of endovascular therapy with a
6.
7.
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CASE REPORT
Stent implantation and optical frequency domain imaging with carbon dioxide for chronic total occlusion in the superficial femoral artery Akihiro Nakamura • Kazuki Noda • Sota Nakajima • Hideaki Endo • Tohru Takahashi Eiji Nozaki
•
Received: 29 August 2014 / Accepted: 6 October 2014 Ó Japanese Association of Cardiovascular Intervention and Therapeutics 2014
Abstract A 68-year-old female was presented with claudication in the left lower leg. She underwent angiography with carbon dioxide (CO2) because she had a history of anaphylactic shock to iodinated contrast medium. It revealed total occlusion of the left superficial femoral artery (SFA), and subsequently endovascular therapy (EVT) was performed by an antegrade approach from the left common femoral artery. After stent implantation, we performed optical frequency domain imaging (OFDI) using CO2 as contrast medium. OFDI has been extensively studied in the coronary circulation; however, its use in the peripheral arterial circulation is scarce. We present a case of stent implantation and OFDI using CO2 as an ancillary tool during EVT for SFA lesions in the patient with contraindication to iodinated contrast medium.
system. Its system is similar to that of intravascular ultrasound (IVUS) and provides a 10-fold higher resolution as compared to IVUS. Although OFDI has now become available in the coronary intervention in Japan, its use has limited in the setting of infrainguinal peripheral artery disease (PAD). The following report is a case of patient with anaphylactic shock to iodinated contrast medium who underwent endovascular therapy (EVT) using CO2 for a total occlusion lesion in the left superficial femoral artery (SFA). In this case, we had a unique opportunity for OFDI imaging using CO2 before and after stent implantation in SFA lesions which cannot be performed in coronary imaging.
Case presentation Keywords Carbon dioxide Stenting Superficial femoral artery Optical frequency domain imaging
Introduction The use of iodinated contrast medium is limited or contraindicated in patients with impaired renal function or a history of anaphylactic shock induced by this agent. In such patients, carbon dioxide (CO2) is available as medium for digital subtraction angiography. Intravascular optical frequency domain imaging (OFDI) is a new imaging modality based on near-infrared light projected via a catheter-based
A. Nakamura (&) K. Noda S. Nakajima H. Endo T. Takahashi E. Nozaki Department of Cardiology, Iwate Prefectural Central Hospital, 1-4-1 Ueda, Morioka, Iwate 020-0096, Japan e-mail: [email protected]
In April 2013, a 68-year-old female patient who presented a clinical medical history of hypertension, diabetes mellitus, smoking, dyslipidemia was referred to our hospital for a 3-month history of intermittent claudication (Fontain classification: IIb) in her left leg. The patient had a surgical history of femoropopliteal prosthetic bypass graft in both legs for total occlusion of the superficial femoral artery (SFA) 9 years previously (Fig. 1). The patient underwent CT angiography with iodinated contrast medium. Soon after the injection of the contrast medium, she went into anaphylactic shock on the CT table. Luckily, the patient was rapidly resuscitated and suffered no permanent harm. Since this accident, the administration of iodinated contrast medium has been considered an absolute contraindication for this patient. In spite of optimal medication for 1 year, the patient showed the progressive symptom in left leg, and the maximum walking distance was about 10–20 m. The
123
A. Nakamura et al.
Fig. 1 Contrast-enhanced CT angiopraphic image of femoropopliteal prosthetic bypass graft and total occlusion of SFA in left leg. CT computed tomography, SFA superficial femoral artery
ankle–brachial index (ABI) at rest was 0.41 for the left leg with monophasic wave forms. We decided to perform interventional procedure to the left SFA. In June 2014, EVT without iodinated contrast medium was performed by a crossover technique from the contralateral side. A 6-Fr 45 cm Destination peripheral guiding sheath (Terumo Medical Corp., Tokyo, Japan) was inserted in retrograde fashion into the left common femoral artery (CFA) after the successful right CFA puncture. Angiography was performed by injection of CO2 from the sheath, and it revealed total occlusion in the SFA mid portion with collaterals supplying the distal portion of the SFA (Fig. 2A). A 0.018-inch ATHLETE Paddler HT guide wire (Japan Lifeline Co. Ltd., Tokyo, Japan) was used to cross the peripheral chronic total occlusion (CTO) lesion in the
123
left SFA with conventional techniques. EVT for CTO lesion in the left SFA was performed using a 5.0 9 100 mm Senri balloon (Terumo Medical Co. Ltd., Tokyo, Japan) with several overlapping inflations. Before stent implantation, the observation by IVUS (Vision PV. 018, Volcano Co. Ltd., San Diego, CA, USA) was performed (Fig. 3). After exchanging with a 0.014-inch Spindle guide wire (St. Jude Medical, Inc., St. Paul, MN, USA), the OFDI catheter (FastView, Treumo Medical Co. Ltd., Tokyo, Japan) was advanced over this wire and the imaging core was placed distal of the total lesion of the SFA. The catheter position was confirmed by the radiopaque markers of the OFDI catheter. At this point, approximately 30 mL of CO2 was hand-injected through the sheath. The catheter was pull-backed automatically at a speed of 40 mm/s, and then OFDI images were depicted by Terumo-OFDI system (LUNAWAVE, Terumo Medical Co. Ltd., Tokyo, Japan) (Figs. 3, 4). Subsequently, stenting with 6.0 9 100 mm, 6.0 9 60 mm SMART Control stents (Cordis, Co. Ltd., Warren, NJ, USA) was performed. Postdilatation was performed with a 6.0 9 100 mm Fox SV balloon (Abbott Vascular Japan Co. Ltd., Tokyo, Japan). OFDI images of the SFA lesions before and after stenting were shown in Fig. 3 (A-2, 3: proximal portion; B-2, 3: mid portion; C-2, 3: distal portion, respectively). Figure 4 shows the representative OFDI images obtained during the EVT procedure. A sufficient stent area was obtained by OFDI using CO2 estimation, and final angiogram using CO2 showed good vessel patency after balloon post-dilatation (Fig. 2B). Thus, EVT procedure using CO2 was carried out without any minor or major events or complications. The X-ray fluoroscopic time was 37.4 min. The patient was discharged 2 days after the EVT procedure. At 1 month after procedure, she was completely free from quality of life-threatening claudication and ABI at rest of the left leg improved from 0.41 to 0.80.
Discussion This is the report of angiography and subsequent stent implantation using CO2 in a patient with a history of anaphylactic shock to iodinated contrast medium. Using CO2, we could also obtain OFDI imaging before and after stent implantation in the SFA lesions. To our knowledge, this is the first reported case using CO2 for OFDI imaging of the SFA lesions. Images by intra-arterial injection of CO2 are made by the replacement of the blood volume, whereas those by iodinated contrast medium are made by the mixture with the blood [1]. Although the images made by CO2 alone are
CO2 angioplasty and OFDI for SFA-CTO Fig. 2 CO2 angiography before and after EVT. A Initial CO2 angiography revealed total occlusion in the left SFA from the mid to the distal portion (a dotted line). B Final CO2 angiography after EVT procedure revealed well-dilated left SFA implanted with two stents. CO2 carbon dioxide, EVT endovascular therapy, SFA superficial femoral artery
not necessarily sufficient to visualize, much progress has been made in the quality of the images by digital subtraction angiography (DSA) and it has enabled us the diagnostic angiography in PAD patients with contraindication to iodinated contrast medium like our case [2]. Futhermore, the images by CO2 DSA have enabled us to perform EVT, especially in iliac and infrainguinal peripheral artery. Kawasaki et al. [3] showed the feasibility, safety and imaging quality of CO2 angiography in EVT for patients with chronic kidney disease as compared with the angiography with iodinated contrast medium. Higashimori et al. [4] recently reported an EVT case of iliac artery lesions in a patient with impaired renal function, and they performed stent implantation in the iliac artery using IVUS and CO2 angiography without iodinated contrast medium. Thus, it has been shown that EVT using CO2 is safe and efficient for high-risk patients with iliofemoral artery disease. In fact, we did not recognize any complication related to air contamination or embolism, and the patient did not complain of lower leg pain during CO2 injection in our case.
OFDI is a Fourier-domain optical coherence tomography (OCT) using swept optical source, and it has been introduced as a new-generation light-based imaging modality [5]. OFDI provides high-speed image acquisition and high-quality image resolution (a 10-fold higher resolution as compared to IVUS) [6], with resulting more detailed depiction and accurate quantitative assessment of intraluminal structures when compared with angiography and IVUS. Terumo-OFDI system can provide images at 158 frames/s with a total of 512 radial scans per circular cross-sectional image and had an axial resolution of \20 lm and a lateral resolution of 30 lm (at 2.5 mm) [7]. Although this modality has now become available in the coronary intervention, it has a limited use in the setting of infrainguinal peripheral artery disease. The hope is for it to be used both before and after EVT to optimize treatment choices and ensure stent wall apposition, but to date, it has only been used on a limited basis. High-quality resolution capabilities of this modality could help before and after EVT to predict outcomes or identify position errors in stent deployment; however, it has one specific limitation,
123
A. Nakamura et al.
Post-Stenting
Pre-Stenting IVUS
CO2-OFDI
B-1
B-3
B-2
1mm
1mm
C-2
C-1
2mm
1mm
1mm
2mm
A-3
A-2
A-1
2mm
CO2-OFDI
1mm
C-3
1mm
Fig. 3 IVUS and OFDI images before and after stenting. A–C Show the proximal, mid, and distal portion levels in the SFA lesions, respectively. 1–3 Show the IVUS images before stenting, OFDI
images before stenting, and OFDI images after stenting, respectively. IVUS intravascular ultrasound, OFDI optical frequency domain imaging, SFA superficial femoral artery
namely, image signals are attenuated by erythrocytes. To overcome this hurdle, other medium such as contrast medium, saline, or dextran needs to be injected in the vessel during acquisition of images. In peripheral circulation, CO2 can be also used as an alternative agent that is contraindicated in coronary circulation. This allowed us a unique opportunity for application of CO2 in the field of peripheral EVT that cannot be performed in coronary interventions. Thus, in our case, CO2 was used not only as contrast media in angiography and EVT for SFA, but also as alternative agent instead of iodinated contrast medium in OFDI imaging. In the field of peripheral EVT, information regarding the images of the vessel, particularly on that of inner side, is rather scanty. As shown in Figs. 3 and 4, OFDI could provide us a high-resolution intravascular imaging as compared with IVUS images. Although its contribution to the clinical benefit is still unclear, the visualization in different aspect from IVUS will give us more information
for the treatment of peripheral arterial disease and will be useful in the judgement of therapeutic effect. There are some limitations in our method. First, we could not compare with OFDI images using other agents such as dextran and iodinated contrast medium. Although there has been no such report to date and we also have no date about comparison of CO2 and iodinated contrast medium, it would be interesting to investigate which agents would be better to obtain highquality OFDI images. If so, use of CO2 would be a viable option in the field of peripheral EVT apart from use in patients with contraindications to iodinated contrast medium. Second, the injection of CO2 could give comparable erythrocyte clearance and imaging quality in our case; however, it has not been well studied whether the full exchange of blood is possible by this method in any case. The possibility exists that the phenomenon such as surface tension occurs, with resulting residual blood in the vessel lumen. We need
123
CO2 angioplasty and OFDI for SFA-CTO
Fig. 4 Representative OFDI (A–F) and the corresponding IVUS images (A-1 to D-1) obtained during the EVT procedure. A Localized calcification was found at 3 o’clock. It showed low signal and low attenuation (asterisk). B Sheet-like dense calcification observed as heterogeneous image was found at 9–12 o’clock (asterisk), and an intimal flap was found at 5 o’clock (arrows). C Minor dissection
within vessel wall was observed at 9–11 o’clock (arrow heads). D Homogenous thick intima or a thrombus was found at 12–1 o’clock (Th). E Overlapping stents with good stent expansion. F Small cavity formation and uncovered stent struts (square surrounded by a dotted line). OFDI optical frequency domain imaging, IVUS intravascular ultrasound, EVT endovascular therapy
further investigation especially the experiment using a simulated model of blood vessel which may give us more important information about the clinical usefulness of OFDI using CO2.
simple homemade carbon dioxide delivery system in patients with ileofemoral artery disease. Circ J. 2012;76(7):1722–8. Higashimori A, Yokoi Y. Stent implantation for chronic total occlusion in the iliac artery using intravascular ultrasound-guided carbon dioxide angiography without iodinated contrast medium. Cardiovasc Interv Ther. 2013;28:415–8. Okumura T, Onuma Y, Garcia-Garcia HM, van Geuns RJ, Wykrzykowska JJ, Schultz C, et al. First-in-man evaluation of intravascular optical frequency domain imaging (OFDI) of Terumo: a comparison with intravascular ultrasound and quantitative coronary angiography. EuroIntervention. 2011;6:1037–45. Templin C, Meyer M, Mu¨ller MF, Djonov V, Hlushchuk R, Dimova I, et al. Coronary optical frequency domain imaging (OFDI) for in vivo evaluation of stent healing: comparison with light and electron microscopy. Eur Heart J. 2010;31(14):1792–801. Okamura T, Serruys PW, Regar E. Three-dimensional visualization of intracoronary thrombus during stent implantation using the second generation, Fourier domain optical coherence tomography. Eur Heart J. 2010;31(5):625.
4.
5. Conflict of interest
There is no conflict of interest of authors.
References 1. Kerrns SR, Hawkins IF Jr, Sabatelli FW. Current status of carbon dioxide angiography. Radiol Clin N Am. 1995;33:15–29. 2. Hawkins IF, Caridi JG. Carbon dioxide (CO2) digital subtraction angiography: 26-year experience at the University of Florida. Eur Radiol. 1998;8:391–402. 3. Kawasaki D, Fujii K, Fukunaga M, Masutani M, Nakata A, Masuyama T. Safety and efficacy of endovascular therapy with a
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7.
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