Transcarotid retrograde stenting for common carotid artery ostial stenosis: how I do it
Stenosis involving the common carotid artery (CCA) ostium is rare, accounting for only 1–2% of all types of carotid artery stenoses . Because ostial stenosis of the CCA, which is a supra-aortic lesion, is located deep in the sternum and ribs, its treatment is difficult and complex compared to that of bifurcation stenosis of the internal carotid artery (ICA). Surgical treatment of ostial stenosis of the CCA mainly involves transthoracic or transcarotid reconstruction. Although surgical treatment is associated with a low recurrence rate, the complication rate is high. In particular, transthoracic reconstruction for supra-aortic trunk stenosis has been reported to be associated with a 16% rate of perioperative stroke/death and accounts for 32% of procedure-related complications . Additionally, the presence of severe pulmonary disease or a previous mediastinotomy performed for myocardial revascularization can increase the risk of surgical treatment. Therefore, endovascular treatment has been the more recently selected approach. Endovascular treatment is mainly divided into antegrade transfemoral and retrograde transcarotid approaches. However, a comparison of these approaches has not been reported, and treatment strategies must be planned according to the patient’s condition. A 74-year-old man with chronic renal failure presented with sudden onset of right hemiparesis. Diffusion-weighted magnetic resonance imaging (MRI) revealed multiple infarctions in the left cerebral hemisphere. Magnetic resonance angiography (MRA) revealed poor visualization of the left CCA ostium to the ICA, whereas visualization of the intracranial cerebral arteries was maintained. MRA performed 3 years prior indicated stenosis of the left CCA ostium (Fig. ). Carotid duplex ultrasonography revealed preservation of the carotid bifurcation, with collateral flow from the external carotid artery (ECA) into the ICA. Although the anterior and posterior communicating arteries were not well developed on MRA, single-photon emission computed tomography (SPECT) using N-isopropyl-p-[123I] iodoamphetamine revealed no reduction in cerebral blood flow. Cerebral angiography was not performed to prevent further deterioration of renal function. Retrograde transcarotid stenting was performed. 

Exposure of the common carotid artery The surgery was performed in a hybrid operating room with the patient under general anesthesia. The patient’s head was vertex down and rotated approximately 15° to the right. A neck incision was made along the sternocleidomastoid muscle (Fig. a). The CCA was widely exposed to facilitate easier execution of subsequent procedures (Fig. b). Balloon guide catheter insertion and setting The proximal and distal portions of the CCA were clamped before the arteriotomy. The distal CCA clip was clamped slightly away from the carotid bifurcation to maintain collateral flow from the ECA to the ICA (Fig. c). A small arteriotomy measuring approximately 1–2 cm was performed. A 9-French (Fr) Optimo (Tokai Medical Products) balloon guide catheter (BGC) was directly inserted through the arteriotomy of the CCA without a sheath, and fixed by inflating the balloon (Fig. d). The BGC was curved and placed toward the legs, allowing the surgeon to perform the procedure on the leg side rather than on the side of the patient’s head. Moreover, the surgeon was able to perform the procedures while facing the monitor, similar to the positioning in normal endovascular treatment (Fig. ). Aspiration of the contrast medium through the balloon guide catheter CCA angiography using a diagnostic 4-Fr catheter from the femoral artery revealed severe ostial stenosis of the CCA. During the procedure, the contrast medium was constantly aspirated through the BGC and only passed through the CCA, with only 11 mL used inside the body (Fig. a-b). A microguidewire was easily passed through the stenosis via the BGC. Transluminal angioplasty with a 6 mm x 40 mm percutaneous transluminal angioplasty balloon (Rx-Genity; Kaneka Medical Products) and subsequent deployment of a 10 mm x 40 mm stent (PRECISE; Kaneka Medical Products) were performed in the usual manner (Fig. c). CCA angiography after stent deployment revealed sufficient dilation of the ostial stenosis (Fig. d) and no scattering of debris into the intracranial blood vessels. Blood in the CCA was suctioned using the BGC before deflating the guide balloon. After removing the BGC, the puncture site was sutured using 6 − 0 monofilament surgical sutures. Postoperative course The postoperative course was uneventful. Diffusion-weighted MRI revealed no new infarctions, and MRA visualization of the CCA and ICA was improved (Fig. ). The patient experienced no further cerebral ischemia or deterioration of renal function. Indications The stability of a guide catheter is very important in endovascular treatment. If the stenotic lesion is at a certain distance from the aorta, the antegrade transfemoral approach seems possible, even for CCA stenosis, and it has been reported to have a high technical success rate . However, in patients with stenosis, where the distance from the aorta to the lesion is short, the stability of the guide catheter deteriorates, and the risk of the procedure increases. With the retrograde transcarotid approach, the position of the guide catheter does not change, even if the stenosis is hardened and resists the passage of the guidewire. Furthermore, even when a fragile thrombus is present, reliable distal protection is possible through balloon inflation of the BGC before the guidewire passes through the stenotic site. In the retrograde transcarotid approach, the guide catheter may easily be pulled out. We rendered the inadvertent extraction of the BGC difficult by directly inserting it into the CCA without a sheath and inflating the balloon. The use of a retrograde transcarotid approach with a short BGC for percutaneous peripheral intervention has been reported . In our patient, in addition to the sheathless method, the BGC was curved and placed toward the leg side to allow the surgeon to face the monitor while performing the surgery. By using a long BGC, the length of the neuroendovascular devices extending from the BGC to the hand is shortened, which increases usability. In addition, the CCA, ICA, and ECA were exposed such that they could be clamped. After the BGC is removed, debris can be reliably removed by de-clamping each blood vessel in a manner similar to that of carotid endarterectomy (CEA). Furthermore, we aspirated contrast medium through the BGC. Our technique allows treatment even in patients with renal dysfunction. In addition, CCA ostial and carotid bifurcation stenoses may coexist. Our hybrid approach allows the simultaneous execution of treatment procedures for both types of stenosis at the same time . Limitations Restenosis is often a problem with carotid artery stenting, and the long-term outcomes of stenting for ostial stenosis of the CCA remain unknown. A disadvantage of the retrograde transcarotid approach is the difficulty of the treatment strategy for in-stent stenoses/occlusions. Generally, adhesion between the blood vessel wall and surrounding tissue strengthens after CEA, increasing surgical risks. Similar to CEA, the retrograde transcarotid approach requires a procedure to expose the CCA and is therefore not suitable for repeated treatments. Restenosis is likely to occur within 2 years of stent placement using the retrograde transcarotid approach . Therefore, frequent follow-ups are necessary, particularly during the early post-treatment period. Furthermore, if the stenosis is very close to the CCA ostium, embolism on the aortic side, such as the contralateral CCA or subclavian artery, is a concern. How to avoid complications Because distal protection is completed before the microguidewire passes through the stenosis, the risk of debris or clots scattered into the intracranial blood vessels during stent placement is small. However, caution is required when deflating guide balloons. Blood was suctioned into the CCA through the BGC several times before the guide balloon was deflated. Intraoperative neuromonitoring is necessary, especially in cases in which a reduction in cerebral blood flow is observed on SPECT. Specific information for the patient This treatment has potential complications of both stent restenosis, which is specific to carotid artery stenting, and cranial nerve palsy, which is specific to CEA. Treatment becomes more difficult when restenosis occurs. In addition, the long-term outcomes of this treatment remain unknown. 

The surgery was performed in a hybrid operating room with the patient under general anesthesia. The patient’s head was vertex down and rotated approximately 15° to the right. A neck incision was made along the sternocleidomastoid muscle (Fig. a). The CCA was widely exposed to facilitate easier execution of subsequent procedures (Fig. b). 

The proximal and distal portions of the CCA were clamped before the arteriotomy. The distal CCA clip was clamped slightly away from the carotid bifurcation to maintain collateral flow from the ECA to the ICA (Fig. c). A small arteriotomy measuring approximately 1–2 cm was performed. A 9-French (Fr) Optimo (Tokai Medical Products) balloon guide catheter (BGC) was directly inserted through the arteriotomy of the CCA without a sheath, and fixed by inflating the balloon (Fig. d). The BGC was curved and placed toward the legs, allowing the surgeon to perform the procedure on the leg side rather than on the side of the patient’s head. Moreover, the surgeon was able to perform the procedures while facing the monitor, similar to the positioning in normal endovascular treatment (Fig. ). 

CCA angiography using a diagnostic 4-Fr catheter from the femoral artery revealed severe ostial stenosis of the CCA. During the procedure, the contrast medium was constantly aspirated through the BGC and only passed through the CCA, with only 11 mL used inside the body (Fig. a-b). A microguidewire was easily passed through the stenosis via the BGC. Transluminal angioplasty with a 6 mm x 40 mm percutaneous transluminal angioplasty balloon (Rx-Genity; Kaneka Medical Products) and subsequent deployment of a 10 mm x 40 mm stent (PRECISE; Kaneka Medical Products) were performed in the usual manner (Fig. c). CCA angiography after stent deployment revealed sufficient dilation of the ostial stenosis (Fig. d) and no scattering of debris into the intracranial blood vessels. Blood in the CCA was suctioned using the BGC before deflating the guide balloon. After removing the BGC, the puncture site was sutured using 6 − 0 monofilament surgical sutures. 

The postoperative course was uneventful. Diffusion-weighted MRI revealed no new infarctions, and MRA visualization of the CCA and ICA was improved (Fig. ). The patient experienced no further cerebral ischemia or deterioration of renal function. 

The stability of a guide catheter is very important in endovascular treatment. If the stenotic lesion is at a certain distance from the aorta, the antegrade transfemoral approach seems possible, even for CCA stenosis, and it has been reported to have a high technical success rate . However, in patients with stenosis, where the distance from the aorta to the lesion is short, the stability of the guide catheter deteriorates, and the risk of the procedure increases. With the retrograde transcarotid approach, the position of the guide catheter does not change, even if the stenosis is hardened and resists the passage of the guidewire. Furthermore, even when a fragile thrombus is present, reliable distal protection is possible through balloon inflation of the BGC before the guidewire passes through the stenotic site. In the retrograde transcarotid approach, the guide catheter may easily be pulled out. We rendered the inadvertent extraction of the BGC difficult by directly inserting it into the CCA without a sheath and inflating the balloon. The use of a retrograde transcarotid approach with a short BGC for percutaneous peripheral intervention has been reported . In our patient, in addition to the sheathless method, the BGC was curved and placed toward the leg side to allow the surgeon to face the monitor while performing the surgery. By using a long BGC, the length of the neuroendovascular devices extending from the BGC to the hand is shortened, which increases usability. In addition, the CCA, ICA, and ECA were exposed such that they could be clamped. After the BGC is removed, debris can be reliably removed by de-clamping each blood vessel in a manner similar to that of carotid endarterectomy (CEA). Furthermore, we aspirated contrast medium through the BGC. Our technique allows treatment even in patients with renal dysfunction. In addition, CCA ostial and carotid bifurcation stenoses may coexist. Our hybrid approach allows the simultaneous execution of treatment procedures for both types of stenosis at the same time . 

Restenosis is often a problem with carotid artery stenting, and the long-term outcomes of stenting for ostial stenosis of the CCA remain unknown. A disadvantage of the retrograde transcarotid approach is the difficulty of the treatment strategy for in-stent stenoses/occlusions. Generally, adhesion between the blood vessel wall and surrounding tissue strengthens after CEA, increasing surgical risks. Similar to CEA, the retrograde transcarotid approach requires a procedure to expose the CCA and is therefore not suitable for repeated treatments. Restenosis is likely to occur within 2 years of stent placement using the retrograde transcarotid approach . Therefore, frequent follow-ups are necessary, particularly during the early post-treatment period. Furthermore, if the stenosis is very close to the CCA ostium, embolism on the aortic side, such as the contralateral CCA or subclavian artery, is a concern. 

Because distal protection is completed before the microguidewire passes through the stenosis, the risk of debris or clots scattered into the intracranial blood vessels during stent placement is small. However, caution is required when deflating guide balloons. Blood was suctioned into the CCA through the BGC several times before the guide balloon was deflated. Intraoperative neuromonitoring is necessary, especially in cases in which a reduction in cerebral blood flow is observed on SPECT. 

This treatment has potential complications of both stent restenosis, which is specific to carotid artery stenting, and cranial nerve palsy, which is specific to CEA. Treatment becomes more difficult when restenosis occurs. In addition, the long-term outcomes of this treatment remain unknown. 

CCA ostial stenosis is rare, and its treatment strategy is difficult and complex. Surgical treatments for CCA ostial stenosis, such as transthoracic or transcarotid reconstruction, have a high complication rate. Recently, endovascular treatment has been more often selected and is mainly divided into antegrade transfemoral and retrograde transcarotid approaches. The stability of the guide catheter is important. With regard to the retrograde transcarotid approach, the position of the guide catheter does not change even if the stenosis was hardened. The BGC is stabilized by directly inserting it into the CCA, without using a sheath, and fixing it by inflating the guide balloon. Early distal protection is made possible simply by inflating the guide balloon. By curving and placing the BGC toward the leg side, the surgeon can perform the procedure while directly facing the monitor. During the procedure, contrast medium is constantly aspirated through the BGC to prevent further renal dysfunction. Blood in the CCA should be suctioned several times via the BGC before deflating the guide balloon. The patient must be informed about the complications of stent restenosis, which is specific to carotid artery stenting, and cranial nerve palsy, which is specific to CEA. 

Below is the link to the electronic supplementary material. ESM 1 (MP4 325 MB) 

