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Outcomes of Endoluminal Therapy for Ostial Disease of the Major Branches of the Aortic Arch
Outcomes of Endoluminal Therapy for Ostial Disease of the Major Branches of the Aortic Arch Andrew M. Bakken,1 Eugene Palchik,1 Wael E. Saad,2 Joseph P. Hart,1 Michael J. Singh,1 Jeffrey M. Rhodes,1 David L. Waldman,2 and Mark G. Davies,1,2 Rochester, New York
While aggressive endoluminal therapy for occlusive disease of the major branches of the arch of the aorta (brachiocephalic [BCA], left common carotid [LCCA], and left subclavian [LSCA] arteries) is commonplace, long-term outcomes in this population are unclear. We examined the long-term outcomes of endoluminal therapy for ostial aortic arch disease at a single tertiary referral academic medical center. A prospective database of patients undergoing endovascular treatment of aortic arch vessel atherosclerotic occlusive disease between 1990 and 2004 was maintained and retrospectively analyzed. Patients with stenotic ostial lesions of the major thoracic aorta branches were selected. Angiograms were reviewed in all cases to assess lesion characteristics. Patency was assessed by routine clinical and, in the LCCA and LSCA, duplex ultrasound follow-up at 1, 6, and 12 months postintervention and every 12 months thereafter. Results were standardized to current Trans-Atlantic Inter-Society Consensus and Society for Vascular Surgery criteria. Kaplan-Meier analyses were performed to assess time-dependent outcomes. Factor analyses were performed using a Cox proportional hazard model for time-dependent variables. Data are presented as mean ± SEM. Forty-four patients (average age 64 ± 2 years, 59% male) underwent 26 LSCA, 11 LCCA, and eight BCA interventions for primary indications of arm ischemia (29%), prevention or treatment of coronary steal syndrome (29%), or cerebrovascular signs/symptoms (42%). The technical success rate was 98%, with a 90-day mortality rate of 0% and a major adverse event rate of 2%. There were no strokes and no upper extremity embolic events. Cumulative patency was 88 ± 8% at 3 years, with a reintervention rate of 7%. The overall symptom recurrence rate was 4%. No local or systemic factors were associated with poor outcomes. Endoluminal stenting for ostial disease of the branches of the aortic arch provides excellent and long-term patency rates with low morbidity, mortality, and secondary intervention rates. With an overall technical success of 98%, our results parallel those for lesions located more distally in the arch branches and support the continued use of percutaneous therapy for atherosclerotic disease throughout the arch branches.
INTRODUCTION Presented at the Eastern Vascular Society Annual Meeting, Washington, DC, September 28-30, 2006. 1 Department of Surgery, Center for Vascular Disease, University of Rochester, Rochester, NY. 2 Department of Imaging Sciences, Center for Vascular Disease, University of Rochester, Rochester, NY.
Correspondence to: Mark G. Davies, MD, PhD, Division of Vascular Surgery, Center for Vascular Disease, University of Rochester, 601 Elmwood Avenue, Box 652, Rochester, NY 14642, USA, E-mail: [email protected] Ann Vasc Surg 2008; 22: 388-394 DOI: 10.1016/j.avsg.2007.07.040 Ó Annals of Vascular Surgery Inc. Published online: April 14, 2008
388
Endovascular intervention for occlusive disease of the major branches of the aortic arch has flourished as it has established itself as a reasonable alternative to operative bypass. However, the response to therapy for different patterns of disease has not been well delineated. Given the experience of treatment effect for ostial and nonostial disease of the renal artery,1 we sought to determine if a similar success rate would be achieved with aortic atherosclerotic disease encroaching on aortic arch ostia. Ostial disease appears to be a different entity from that encountered within the vessels. Therefore, the aim of
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this study was to examine the results of endovascular treatment for ostial disease of the brachiocephalic (BCA), left common carotid (LCCA), and left subclavian (LSCA) arteries.
METHODS Study Setting This study was performed at an academic medical center in a metropolitan area of 300,000 persons and a surrounding county of w1 million in western New York State. The University of Rochester Medical Center is a tertiary referral center with a dedicated vascular service line. Experimental Design We performed a retrospective analysis of a prospectively maintained database of consecutive patients treated via endoluminal intervention for atherosclerotic disease of the major primary branches of the thoracic aortic arch from 1990 through 2004. Those patients treated for ostial stenotic disease of the aortic arch were selected for analysis. Patients undergoing primary operative reconstruction during the study period (74 cases) were not included in the analysis. Determination of the need for therapy and selection of the therapeutic modality for individual patients were both dictated by individual attending physician preference and not regulated by unit guidelines. Immediate technical failures were identified and included to allow for an intention-to-treat analysis. Patients underwent routine clinical and, in the LCCA and LSCA, duplex ultrasound followup at 1, 6, and 12 months postintervention and every 12 months thereafter, with 98% of patients completing follow-up. Given the difficulty visualizing aortic branch vessels noninvasively, hemodynamic success was considered immediate and sustained normalization of upper extremity blood pressures. Procedures to maintain patency and any procedures performed in the event of occlusion of the index segment were recorded. Results were standardized to current Trans-Atlantic Inter-Society Consensus (TASC) and Society for Vascular Surgery (SVS) criteria. Methods For each patient, demographics, symptoms, existing comorbid conditions, and risk factors for atherosclerosis were identified. Periprocedural parameters were obtained from the record. All duplex ultrasound scans were performed at approved vascular laboratories accredited by the Intersociety Commission on Accreditation of Vascular Laboratories. For all
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interventions since 2001 (n ¼ 38), patients were given clopidogrel (75 mg/dL) and aspirin (81 mg/ dL) beginning 3 days before the intervention. After the intervention, clopidogrel was continued for 1 month and aspirin was continued for life. Prior to 2001, patients (n ¼ 7) were maintained on aspirin alone or in combination with ticlopidine. All patients received an intravenous heparin bolus (100 U/kg) to achieve systemic anticoagulation during the intervention. A stent was placed in 93% (42 of 45) of these ostial interventions and ranged in diameter from 6 to 12 mm, with lengths ranging from 18 to 30 mm. Type of stent varied and was chosen at the discretion of the provider. An embolic protection device was employed in five of 11 LCCA interventions and in no LSCA or BCA interventions. The procedure was concluded when angiographic success was achieved based on a residual stenosis of <30% and without evidence of dissection or thrombosis. In the absence of other significant concurrent health problems, most patients were discharged on the evening of the procedure or on postprocedure day 1. Definitions Ostial lesions were defined as stenoses located within 5 mm of the aortic lumen. Coronary artery disease was defined as a history of angina pectoris, myocardial infarction, congestive heart disease, or prior coronary artery revascularizations. Cerebrovascular disease included a history of stroke, transient ischemic attack, or carotid artery revascularization. Metabolic syndrome was defined as previously described2 (insulin resistance or impaired glucose tolerance, hypertension, dyslipidemia, and abdominal obesity), with the exception of abdominal circumference, which was not routinely recorded. We substituted a body mass index 27.0 as a positive score instead of an abdominal circumference >102 cm or >88 cm for male or female patients, respectively. A death within 30 days of the procedure was considered procedure-related. In order to evaluate for mortality rates beyond clinical follow-up, Webbased social security death indices were queried for each of the 44 patients evaluated. A major complication was defined as any event, regardless of how minimal, not routinely observed after endoluminal therapy that required treatment with a therapeutic intervention or rehospitalization within 30 days of the procedure. Clinical success was defined as resolution of presenting symptoms. A 3:1 increase in the peak systolic velocity (PSV) ratio on duplex imaging was defined as restenosis. Patency was defined by current SVS criteria.
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Statistical Analysis
Table I. Patient demographics and comorbidities
All statistical analyses were performed on a ‘‘treatment-received’’ basis. Measured values are reported as percentages or means ± 1 standard deviation. Survival, patency, and stroke-free event rates were calculated using Kaplan-Meier analysis and are reported using current SVS criteria. Standard errors are reported in Kaplan-Meier analyses. The log rank test was used to determine differences between life tables. Cox proportional hazards analysis was used to determine the influence of preprocedural and periprocedural factors on outcomes. Analyses were performed using JMP software, version 5.0.1 (SAS Institute, Cary, NC).
Characteristic
RESULTS Patient Population Over the 15-year study period, we treated by endoluminal intervention a total of 251 aortic arch branch vessels. Among these, we identified 45 stenotic vessels treated for ostial disease in 44 patients (26 men [59%] and 18 women [41%]), with a mean age at intervention of 64 ± 2 years (range 32-85). This included therapy for ostial disease of the BCA in eight patients, the LCCA in 11 patients, and the LSCA in 26 patients. Patient comorbidities and demographics are presented in Table I. The primary indication for intervention differed slightly for each group, with left internal mammary artery steal in patients with a history of aortocoronary bypass being most common among the LSCA interventions, followed closely by left upper extremity exertional arm pain. Among patients undergoing BCA intervention, arm claudication was the commonest primary indication. Treatment of the LCCA was usually undertaken for symptoms of transient ischemic attacks following confirmation of lesion presence by noninvasive imaging. Symptom presentation for the patient cohort is listed in Table II. Procedural Variables Access for each intervention was gained via the femoral artery (n ¼ 31), brachial artery (n ¼ 12), combined femoral and brachial (n ¼ 1), or, in the case of one LCCA intervention, direct retrograde carotid artery puncture after cervical incision. The lesions were all stenotic (60-90% at the time of intervention) and ranged in length from 1 to 2 cm. All had calcification noted on plain films. Lesions were primarily stented in 42 of 45 cases (93%). The three
Demographics Male Female Vessels treated Average age (years) Average follow-up (years) BCA interventions LSCA interventions LCCA interventions Comorbidities Smoking history History of CABG/PCI Hypertension Coagulopathy Diabetes mellitus Hypothyroidism Hyperlipidemia End-stage renal disease on hemodialysis Chronic renal insufficiency
n (%)
26 (59) 18 (41) 45 (100) 64 ± 2 2.8 ± 0.4 8 (18) 26 (58) 11 (24) 35 26 41 2 10 6 33 2 8
(78) (58) (91) (5) (22) (13) (73) (4) (18)
CABG, coronary artery bypass graft; PCI, percutaneous coronary intervention. When indicated, data are presented as mean ± standard error of the mean.
cases not receiving a stent were in the LSCA cohort. In one of these three cases, no intervention was performed because a wire could not be passed through the lesion. In another case, it was felt that LSCA tortuosity at its takeoff precluded stent placement. No discussion of stent placement was documented in the third case. The specific type of stent placed was documented in 36 of the 42 cases of stent placement and varied among 10 different stents. The choice of stent was dependent on the operator and available in-house stock. These included 23 balloon-expandable and 13 self-expanding stents. Deployment of an embolic protection device was attempted and succeeded in five of the 11 LCCA interventions. Surgical distal protection was employed in the patient undergoing LCCA intervention via cervical neck incision and direct retrograde surgical puncture. The remaining five patients undergoing LCCA intervention who did not receive embolic protection were treated earlier in the study period, reflecting the change in treatment paradigm. Outcomes The initial technical success rate was 98% (44 of 45 interventions). The one technical failure occurred in the LSCA cohort due to inability to pass a wire through the ostial lesion to facilitate treatment. There were no periprocedural mortalities. Likewise, the 30- and 90-day all-cause mortality rates were
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Table II. Symptoms of ostial lesions at initial presentation Symptoms
n (%)
BCA (n ¼ 8) Exertional arm pain 4 (50) Neurological symptoms 3 (38) Pre-CABG inflow to RIMA (asymptomatic) 1 (13) LCCA (n ¼ 11) TIA from isolated CCA lesion 4 (36) TIA from tandem CCA/ICA lesions 3 (27) Asymptomatic with isolated CCA lesion 4 (36) Asymptomatic with tandem CCA/ICA lesions 0 (0) LSCA (n ¼ 26) Coronary steal syndrome 11 (42) Exertional arm pain 8 (31) VBI/subclavian steal 5 (19) AVF failure 1 (4) Pre-CABG inflow to LIMA 1 (4) CABG, coronary artery bypass graft; RIMA, right internal mammary artery; TIA, transient ischemic attack; CCA, common carotid artery; ICA, internal carotid artery; VBI, vertebral-basilar insufficiency.
Table III. Mortality and morbidity Complication
Mortality 30-day all-cause 90-day all-cause Morbidity Stroke Transient ischemic attack Myocardial infarction Congestive heart failure Acute renal failure Access siteerelated Hematoma Distal occlusion Pseudoaneurysm
n (%)
0 (0) 0 (0) 0 1 0 0 0
(0) (2) (0) (0) (0)
2 (4) 2 (4) 1 (2)
0% Table III. Additionally, no stroke or persistent neurological event was identified in any patient through the course of follow-up. The major adverse event rate was 2% and involved transient neurological symptoms in a patient undergoing intervention for an LCCA lesion who also had chronic occlusion of the contralateral carotid artery. Symptoms were first noted while positioning the catheter tip near the LCCA ostium. The lesion was successfully stented, and the patient’s neurological status returned to baseline within 12 hr. A postprocedure head computed tomographic (CT) scan showed no evidence of stroke. The access site complication rate was 11% and included two instances of local hematoma formation, one pseudoaneurysm successfully treated with
thrombin injection, and two vessel thromboses distal to the sheath at access sites, one brachial and one femoral (Table III). Both were successfully treated with Fogarty catheter thrombectomy without negative sequelae. No embolic complications were identified. The 1-, 2-, and 3-year primary patency rates were 92 ± 5%, 84 ± 8%, and 77 ± 11%, respectively (Fig. 1). These rates reflect a total of five failed primary interventions over the period of follow-up. Of the two failed LCCA interventions, one occluded asymptomatically and was therefore not reintervened upon observation of adequate flow in the contralateral artery. The other LCCA underwent cryoplasty for asymptomatic in-stent restenosis recognized by duplex ultrasound at 2.3 years. Of two failed LSCA interventions, one failed due to inability to pass the guidewire at the time of intervention, while the other was found to have a blood pressure differential of 90 mm Hg at 1 month postintervention, despite having initial anatomical and hemodynamic success. This patient was not initially stented at the primary intervention due to vessel tortuosity and subsequently underwent carotidesubclavian bypass. The only failed primary BCA intervention was found to have in-stent restenosis at 1.3 years postintervention and was treated by balloon angioplasty at that time, before ultimately undergoing open surgical bypass at 3.8 years postintervention. This yielded 1-, 2-, and 3-year assisted primary patency rates of 95 ± 3%, 88 ± 8%, and 78 ± 11%, respectively. The 1-, 2-, and 3-year secondary patency rates were 95 ± 5%, 88 ± 8%, and 88 ± 8%, respectively (Figs. 2 and 3). Over the course of follow-up, symptom recurrence was noted in two of the 44 treated vessels (5%). This was comprised of one recurrence in the BCA group (13%) and one recurrence in the LSCA group (4%). Cox proportional hazards analysis was undertaken to investigate the impact of pre- and perioperative factors related to outcomes of primary, assisted primary, and secondary patencies. When analyzing across the patient cohort as a whole, no factor was significantly associated.
DISCUSSION The approach to supra-aortic trunk revascularization falls into three general categories: transthoracic, extrathoracic, and endovascular. Where advocated, the transthoracic approach is typically applied to major BCA disease or significant multivessel arch branch disease. It has demonstrated excellent longterm durability, with 10-year cumulative patency
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Fig. 1. Primary patency after percutaneous angioplasty and stenting of lesions of the noncoronary arch ostia. Hatched lines indicate where standard error exceeds 10%. Numbers at risk are shown in the table at the base of the figure.
Fig. 2. Assisted primary patency following repeat endovascular interventions for two of the total of five treatment failures. Hatched lines indicate where standard error exceeds 10%. Numbers at risk are shown in the table at the base of the figure.
rates in two of the largest series ranging 88-94%.3,4 In these series, Berguer et al.4 and Takach et al.3 reported operative mortality rates of 6% and 3%, respectively, and stroke rates of 10% and 3%, respectively. Additional morbidity included myocardial infarction, upper extremity swelling, pericardial tamponade, and sternal wound infection. Concern over these peri- and postoperative events has led many to utilize an extrathoracic, typically cervical, approach to manage patients with less extensive or single-vessel supra-aortic trunk disease or those with substantial comorbidities thought to make transthoracic repair prohibitively risky. In this setting, extrathoracic bypass has demonstrated 5-year cumulative patency ranging from 91-100% and 10year cumulative patency in the range 82-88%.5-8
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Fig. 3. Secondary patency following repeat endovascular intervention for reoccluded ostial lesion of the BCA. Hatched lines indicate where standard error exceeds 10%. Numbers at risk are shown in the table at the base of the figure.
Among two of the largest series of such patients, again by the groups Berguer et al.4 and Takach et al.3 but in separate publications from the aforementioned transthoracic data, operative mortality was 0.5% and 0.9%, respectively, while stroke rates were 3.8% and 1.3%, respectively. Additional morbidity included myocardial infarction, pulmonary complications, and graft infection; but the overall rate was less than in the case of transthoracic repair. In spite of this proven record for operative bypass in achieving superior long-term durability,3-8 percutaneous therapy for aortic arch branch disease has flourished, as it has in all vascular beds.9 This growth is related to certain inherent advantages over open surgical methods, including minimal invasiveness and avoidance of general anesthesia, leading to greater patient acceptance, among other reasons. Additionally, percutaneous therapy has been reported to produce lower costs, at least initially, when compared to open surgical therapy.7 We report outcomes on 44 patients undergoing endovascular treatment by way of balloon angioplasty (in 98%) and primary stenting (in 93%) of 45 ostial lesions of the aortic arch. In contrast to existing reports on percutaneous therapy for supraaortic branch disease, we chose to focus on ostial lesions out of concern that they may represent extension of aortic disease encroaching on the ostium with intervention outcomes that may differ from those of more distal disease, as is the case in renal ostial lesions.1,10,11 Ultimately, we achieved a 98% technical success rate with a cumulative patency rate of 88% at 3 years and a reintervention rate of 7% at an average of 2 years and 10 months clinical follow-up. These results are comparable
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with those reported to date for lesions encompassing all segments of the arch branches. Additionally, this level of patency was attained without any strokes or deaths within the postoperative period and with a low morbidity rate. Reports on endoluminal therapy for lesions of the supra-aortic branches began with balloon angioplasty and demonstrated rates of initial technical success ranging 88-100%, with some indication that rates were lower in the setting of occluded vessels relative to stenotic vessels.12-17 Cumulative patencies at around 3 years of follow-up were reported to range 86-98%, although one report including nine patients with occlusions reported a clinical success rate of 56% at a mean follow-up of 29 months.18 Subsequently, in the mid-1990s, reports of primary stenting began to emerge as aortic branch lesions were more aggressively pursued with endovascular therapy. Technical success rates again were high, ranging 92-100%.19-24 Bates et al.22 and Sullivan et al.,21 the largest such series to date, along with Takach et al.,7 have reported 3-year patency rates of 84-86%, all of which are in line with our own cumulative patency at 3 years of 88% after our initial technical success rate of 98%. These results suggest that stenting for ostial lesions yields results in line with stenting for lesions throughout the supra-aortic branches. It should be noted that, while others have reported differences in patency outcomes between the BCA and LSCA,24 we cannot make any such judgments because of our small number of patients (8) undergoing treatment of ostial innominate disease. In our series of 44 patients including 11 who underwent stenting of the LCCA, we encountered no periprocedural or postintervention strokes and one transient ischemic attack. In comparison, Takach et al.7 noted a stroke rate of 0%, while Sullivan et al.21 encountered two ischemic strokes (14%) among 14 patients undergoing common carotid artery intervention. It may be important to note that we, like Takach et al., utilized a transfemoral approach in treating common carotid artery lesions with one exception, while Sullivan et al. utilized a direct retrograde approach following neck incision and, in the two cases of stroke, performed bifurcation endarterectomy. It may be that direct manipulation of the carotid artery places the vessel at greater risk of ischemic events. Additionally, six of our LCCA interventions involved some form of distal embolic protection, while the remaining five, having been performed earlier in our experience, did not involve any attempt at distal protection. It is our current policy to employ a distal embolic protection device in all carotid interventions whenever
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it can be safely achieved. However, one caveat must be made. This was a retrospective trial. Patients were not seen routinely postoperatively by a neurologist and did not undergo formal neurological evaluations. Self-reporting of neurological events can be three times lower than independently adjudicated events. By way of Cox proportional hazards analysis, we investigated the impact of all pre- and perioperative factors on treated vessel patency and survival and found no significant association with any of the factors studied. Notably, while some have found associations in outcomes with factors such as number of stents placed,2 low stent diameters,24 and hypothyroidism,22 we found no such significant association in our series. This is, however, not entirely surprising given the relatively small number of patients in this series. We conclude that our results support the continued use of percutaneous therapy to treat focal lesions of the BCA, LCCA, and LSCA, including those of the branch ostia. We do not find a decrease in initial or long-term patency or an increase in morbidity or mortality in treating solely ostial lesions relative to reports of more broadly based interventions of the supra-aortic branches. Furthermore, it retains a low morbidity and mortality rate, well below that published for open bypass procedures. REFERENCES 1. Baumgartner I, von Aesch K, Do DD, et al. Stent placement in ostial and nonostial atherosclerotic renal arterial stenoses: a prospective follow-up study. Radiology 2000;216:498-505. 2. Grundy SM, Brewer HB, Jr, Cleeman JI, et al.; for the Conference Participants. Definition of metabolic syndrome: report of the National Heart, Lung, and Blood Institute/ American Heart Association conference on scientific issues related to definition. Circulation 2004;109:433-438. 3. Takach TJ, Reul GJ, Cooley DA, et al. Brachiocephalic reconstruction I: operative and long-term results for complex disease. J Vasc Surg 2005;42:47-54. 4. Berguer R, Morasch MD, Kline RA. Transthoracic repair of innominate and common carotid artery disease: immediate and long-term outcome for 100 consecutive surgical reconstructions. J Vasc Surg 1998;27:34-42. 5. Fry WR, Jartin JD, Clagett GP, et al. Extrathoracic carotid reconstruction: the subclavian-carotid artery bypass. J Vasc Surg 1992;15:83-88. 6. Perler BA, Williams GM. Carotidesubclavian bypassda decade of experience. J Vasc Surg 1990;12:716-722. 7. Takach TJ, Duncan JM, Livesay JJ, et al. Brachiocephalic reconstruction II: operative and endovascular management of single-vessel disease. J Vasc Surg 2005;42:55-61. 8. Berguer R, Morasch MD, Kline RA, et al. Cervical reconstruction of the supra-aortic trunks: a 16-year experience. J Vasc Surg 1999;29:239-248. 9. Anderson PL, Gelijins A, Moskowitz A, et al. Understanding trends in inpatient surgical volume: vascular interventions, 1980-2000. J Vasc Surg 2004;39:1200-1208.
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10. Cicuto KP, McLean GK, Oleaga JA, et al. Renal artery stenosis: anatomic classification for percutaneous transluminal angioplasty. AJR Am J Roentgenol 1981;137: 599-601. 11. van den Ven PJ, Kaatee R, Beutler JJ, et al. Arterial stenting and balloon angioplasty in ostial atherosclerotic renovascular disease: a randomised trial. Lancet 1999;353: 282-286. 12. Huttl K, Nemes B, Simonffy A, et al. Angioplasty of the innominate artery in 89 patients: experience over 19 years. Cardiovasc Intervent Radiol 2002;25:109-114. 13. Millaire A, Trinca M, Marache P, et al. Subclavian angioplasty: immediate and late results in 50 patients. Catheter Cardiovasc Diagn 1993;29:8-17. 14. Mathias KD, Luth I, Haarmann P. Percutaneous transluminal angioplasty of proximal subclavian artery occlusions. Cardiovasc Intervent Radiol 1993;16:214-218. 15. Selby JB, Jr, Matsumoto AH, Tegtmeyer CJ, et al. Balloon angioplasty above the aortic arch: immediate and long-term results. AJR Am J Roentgenol 1993;160:631-635. 16. Dorros G, Lewin RF, Jamnadas P, et al. Peripheral transluminal angioplasty of the subclavian and innominate arteries utilizing the brachial approach: acute outcome and followup. Cathet Cardiovasc Diagn 1990;19:71-76. 17. Duber C, Klose KJ, Kopp H, et al. Percutaneous transluminal angioplasty for occlusion of the subclavian artery: short- and
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long-term results. Cardiovasc Intervent Radiol 1992;15: 205-210. Hebrang A, Maskovic J, Tomac B. Percutaneous transluminal angioplasty of the subclavian arteries: long-term results in 52 patients. AJR Am J Roentgenol 1991;156:1091-1094. Queral LA, Criado FJ. The treatment of focal aortic arch branch lesions with Palmaz stents. J Vasc Surg 1996;23: 368-375. Sueoka BL. Percutaneous transluminal stent placement to treat subclavian steal syndrome. J Vasc Interv Radiol 1996; 7:351-356. Sullivan TM, Gray BH, Bacharach JM, et al. Angioplasty and primary stenting of the subclavian, innominate, and common carotid arteries in 83 patients. J Vasc Surg 1998;28: 1059-1065. Bates MC, Broce M, Lavigne PS, et al. Subclavian artery stenting: factors influencing long-term outcome. Catheter Cardiovasc Interv 2004;61:5-11. Brountzos EN, Petersen B, Binkert C, et al. Primary stenting of subclavian and innominate artery occlusive disease: a single center’s experience. Cardiovasc Intervent Radiol 2004;27:616-623. Przewlocki T, Kablak-Ziembicka A, Pieniazek P, et al. Determinants of immediate and long-term results of subclavian and innominate artery angioplasty. Catheter Cardiovasc Interv 2006;67:519-526.
While aggressive endoluminal therapy for occlusive disease of the major branches of the arch of the aorta (brachiocephalic [BCA], left common carotid [LCCA], and left subclavian [LSCA] arteries) is commonplace, long-term outcomes in this population are unclear. We examined the long-term outcomes of endoluminal therapy for ostial aortic arch disease at a single tertiary referral academic medical center. A prospective database of patients undergoing endovascular treatment of aortic arch vessel atherosclerotic occlusive disease between 1990 and 2004 was maintained and retrospectively analyzed. Patients with stenotic ostial lesions of the major thoracic aorta branches were selected. Angiograms were reviewed in all cases to assess lesion characteristics. Patency was assessed by routine clinical and, in the LCCA and LSCA, duplex ultrasound follow-up at 1, 6, and 12 months postintervention and every 12 months thereafter. Results were standardized to current Trans-Atlantic Inter-Society Consensus and Society for Vascular Surgery criteria. Kaplan-Meier analyses were performed to assess time-dependent outcomes. Factor analyses were performed using a Cox proportional hazard model for time-dependent variables. Data are presented as mean ± SEM. Forty-four patients (average age 64 ± 2 years, 59% male) underwent 26 LSCA, 11 LCCA, and eight BCA interventions for primary indications of arm ischemia (29%), prevention or treatment of coronary steal syndrome (29%), or cerebrovascular signs/symptoms (42%). The technical success rate was 98%, with a 90-day mortality rate of 0% and a major adverse event rate of 2%. There were no strokes and no upper extremity embolic events. Cumulative patency was 88 ± 8% at 3 years, with a reintervention rate of 7%. The overall symptom recurrence rate was 4%. No local or systemic factors were associated with poor outcomes. Endoluminal stenting for ostial disease of the branches of the aortic arch provides excellent and long-term patency rates with low morbidity, mortality, and secondary intervention rates. With an overall technical success of 98%, our results parallel those for lesions located more distally in the arch branches and support the continued use of percutaneous therapy for atherosclerotic disease throughout the arch branches.
INTRODUCTION Presented at the Eastern Vascular Society Annual Meeting, Washington, DC, September 28-30, 2006. 1 Department of Surgery, Center for Vascular Disease, University of Rochester, Rochester, NY. 2 Department of Imaging Sciences, Center for Vascular Disease, University of Rochester, Rochester, NY.
Correspondence to: Mark G. Davies, MD, PhD, Division of Vascular Surgery, Center for Vascular Disease, University of Rochester, 601 Elmwood Avenue, Box 652, Rochester, NY 14642, USA, E-mail: [email protected] Ann Vasc Surg 2008; 22: 388-394 DOI: 10.1016/j.avsg.2007.07.040 Ó Annals of Vascular Surgery Inc. Published online: April 14, 2008
388
Endovascular intervention for occlusive disease of the major branches of the aortic arch has flourished as it has established itself as a reasonable alternative to operative bypass. However, the response to therapy for different patterns of disease has not been well delineated. Given the experience of treatment effect for ostial and nonostial disease of the renal artery,1 we sought to determine if a similar success rate would be achieved with aortic atherosclerotic disease encroaching on aortic arch ostia. Ostial disease appears to be a different entity from that encountered within the vessels. Therefore, the aim of
Vol. 22, No. 3, 2008
this study was to examine the results of endovascular treatment for ostial disease of the brachiocephalic (BCA), left common carotid (LCCA), and left subclavian (LSCA) arteries.
METHODS Study Setting This study was performed at an academic medical center in a metropolitan area of 300,000 persons and a surrounding county of w1 million in western New York State. The University of Rochester Medical Center is a tertiary referral center with a dedicated vascular service line. Experimental Design We performed a retrospective analysis of a prospectively maintained database of consecutive patients treated via endoluminal intervention for atherosclerotic disease of the major primary branches of the thoracic aortic arch from 1990 through 2004. Those patients treated for ostial stenotic disease of the aortic arch were selected for analysis. Patients undergoing primary operative reconstruction during the study period (74 cases) were not included in the analysis. Determination of the need for therapy and selection of the therapeutic modality for individual patients were both dictated by individual attending physician preference and not regulated by unit guidelines. Immediate technical failures were identified and included to allow for an intention-to-treat analysis. Patients underwent routine clinical and, in the LCCA and LSCA, duplex ultrasound followup at 1, 6, and 12 months postintervention and every 12 months thereafter, with 98% of patients completing follow-up. Given the difficulty visualizing aortic branch vessels noninvasively, hemodynamic success was considered immediate and sustained normalization of upper extremity blood pressures. Procedures to maintain patency and any procedures performed in the event of occlusion of the index segment were recorded. Results were standardized to current Trans-Atlantic Inter-Society Consensus (TASC) and Society for Vascular Surgery (SVS) criteria. Methods For each patient, demographics, symptoms, existing comorbid conditions, and risk factors for atherosclerosis were identified. Periprocedural parameters were obtained from the record. All duplex ultrasound scans were performed at approved vascular laboratories accredited by the Intersociety Commission on Accreditation of Vascular Laboratories. For all
Endoluminal Therapy of Arch Ostial Disease 389
interventions since 2001 (n ¼ 38), patients were given clopidogrel (75 mg/dL) and aspirin (81 mg/ dL) beginning 3 days before the intervention. After the intervention, clopidogrel was continued for 1 month and aspirin was continued for life. Prior to 2001, patients (n ¼ 7) were maintained on aspirin alone or in combination with ticlopidine. All patients received an intravenous heparin bolus (100 U/kg) to achieve systemic anticoagulation during the intervention. A stent was placed in 93% (42 of 45) of these ostial interventions and ranged in diameter from 6 to 12 mm, with lengths ranging from 18 to 30 mm. Type of stent varied and was chosen at the discretion of the provider. An embolic protection device was employed in five of 11 LCCA interventions and in no LSCA or BCA interventions. The procedure was concluded when angiographic success was achieved based on a residual stenosis of <30% and without evidence of dissection or thrombosis. In the absence of other significant concurrent health problems, most patients were discharged on the evening of the procedure or on postprocedure day 1. Definitions Ostial lesions were defined as stenoses located within 5 mm of the aortic lumen. Coronary artery disease was defined as a history of angina pectoris, myocardial infarction, congestive heart disease, or prior coronary artery revascularizations. Cerebrovascular disease included a history of stroke, transient ischemic attack, or carotid artery revascularization. Metabolic syndrome was defined as previously described2 (insulin resistance or impaired glucose tolerance, hypertension, dyslipidemia, and abdominal obesity), with the exception of abdominal circumference, which was not routinely recorded. We substituted a body mass index 27.0 as a positive score instead of an abdominal circumference >102 cm or >88 cm for male or female patients, respectively. A death within 30 days of the procedure was considered procedure-related. In order to evaluate for mortality rates beyond clinical follow-up, Webbased social security death indices were queried for each of the 44 patients evaluated. A major complication was defined as any event, regardless of how minimal, not routinely observed after endoluminal therapy that required treatment with a therapeutic intervention or rehospitalization within 30 days of the procedure. Clinical success was defined as resolution of presenting symptoms. A 3:1 increase in the peak systolic velocity (PSV) ratio on duplex imaging was defined as restenosis. Patency was defined by current SVS criteria.
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Statistical Analysis
Table I. Patient demographics and comorbidities
All statistical analyses were performed on a ‘‘treatment-received’’ basis. Measured values are reported as percentages or means ± 1 standard deviation. Survival, patency, and stroke-free event rates were calculated using Kaplan-Meier analysis and are reported using current SVS criteria. Standard errors are reported in Kaplan-Meier analyses. The log rank test was used to determine differences between life tables. Cox proportional hazards analysis was used to determine the influence of preprocedural and periprocedural factors on outcomes. Analyses were performed using JMP software, version 5.0.1 (SAS Institute, Cary, NC).
Characteristic
RESULTS Patient Population Over the 15-year study period, we treated by endoluminal intervention a total of 251 aortic arch branch vessels. Among these, we identified 45 stenotic vessels treated for ostial disease in 44 patients (26 men [59%] and 18 women [41%]), with a mean age at intervention of 64 ± 2 years (range 32-85). This included therapy for ostial disease of the BCA in eight patients, the LCCA in 11 patients, and the LSCA in 26 patients. Patient comorbidities and demographics are presented in Table I. The primary indication for intervention differed slightly for each group, with left internal mammary artery steal in patients with a history of aortocoronary bypass being most common among the LSCA interventions, followed closely by left upper extremity exertional arm pain. Among patients undergoing BCA intervention, arm claudication was the commonest primary indication. Treatment of the LCCA was usually undertaken for symptoms of transient ischemic attacks following confirmation of lesion presence by noninvasive imaging. Symptom presentation for the patient cohort is listed in Table II. Procedural Variables Access for each intervention was gained via the femoral artery (n ¼ 31), brachial artery (n ¼ 12), combined femoral and brachial (n ¼ 1), or, in the case of one LCCA intervention, direct retrograde carotid artery puncture after cervical incision. The lesions were all stenotic (60-90% at the time of intervention) and ranged in length from 1 to 2 cm. All had calcification noted on plain films. Lesions were primarily stented in 42 of 45 cases (93%). The three
Demographics Male Female Vessels treated Average age (years) Average follow-up (years) BCA interventions LSCA interventions LCCA interventions Comorbidities Smoking history History of CABG/PCI Hypertension Coagulopathy Diabetes mellitus Hypothyroidism Hyperlipidemia End-stage renal disease on hemodialysis Chronic renal insufficiency
n (%)
26 (59) 18 (41) 45 (100) 64 ± 2 2.8 ± 0.4 8 (18) 26 (58) 11 (24) 35 26 41 2 10 6 33 2 8
(78) (58) (91) (5) (22) (13) (73) (4) (18)
CABG, coronary artery bypass graft; PCI, percutaneous coronary intervention. When indicated, data are presented as mean ± standard error of the mean.
cases not receiving a stent were in the LSCA cohort. In one of these three cases, no intervention was performed because a wire could not be passed through the lesion. In another case, it was felt that LSCA tortuosity at its takeoff precluded stent placement. No discussion of stent placement was documented in the third case. The specific type of stent placed was documented in 36 of the 42 cases of stent placement and varied among 10 different stents. The choice of stent was dependent on the operator and available in-house stock. These included 23 balloon-expandable and 13 self-expanding stents. Deployment of an embolic protection device was attempted and succeeded in five of the 11 LCCA interventions. Surgical distal protection was employed in the patient undergoing LCCA intervention via cervical neck incision and direct retrograde surgical puncture. The remaining five patients undergoing LCCA intervention who did not receive embolic protection were treated earlier in the study period, reflecting the change in treatment paradigm. Outcomes The initial technical success rate was 98% (44 of 45 interventions). The one technical failure occurred in the LSCA cohort due to inability to pass a wire through the ostial lesion to facilitate treatment. There were no periprocedural mortalities. Likewise, the 30- and 90-day all-cause mortality rates were
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Table II. Symptoms of ostial lesions at initial presentation Symptoms
n (%)
BCA (n ¼ 8) Exertional arm pain 4 (50) Neurological symptoms 3 (38) Pre-CABG inflow to RIMA (asymptomatic) 1 (13) LCCA (n ¼ 11) TIA from isolated CCA lesion 4 (36) TIA from tandem CCA/ICA lesions 3 (27) Asymptomatic with isolated CCA lesion 4 (36) Asymptomatic with tandem CCA/ICA lesions 0 (0) LSCA (n ¼ 26) Coronary steal syndrome 11 (42) Exertional arm pain 8 (31) VBI/subclavian steal 5 (19) AVF failure 1 (4) Pre-CABG inflow to LIMA 1 (4) CABG, coronary artery bypass graft; RIMA, right internal mammary artery; TIA, transient ischemic attack; CCA, common carotid artery; ICA, internal carotid artery; VBI, vertebral-basilar insufficiency.
Table III. Mortality and morbidity Complication
Mortality 30-day all-cause 90-day all-cause Morbidity Stroke Transient ischemic attack Myocardial infarction Congestive heart failure Acute renal failure Access siteerelated Hematoma Distal occlusion Pseudoaneurysm
n (%)
0 (0) 0 (0) 0 1 0 0 0
(0) (2) (0) (0) (0)
2 (4) 2 (4) 1 (2)
0% Table III. Additionally, no stroke or persistent neurological event was identified in any patient through the course of follow-up. The major adverse event rate was 2% and involved transient neurological symptoms in a patient undergoing intervention for an LCCA lesion who also had chronic occlusion of the contralateral carotid artery. Symptoms were first noted while positioning the catheter tip near the LCCA ostium. The lesion was successfully stented, and the patient’s neurological status returned to baseline within 12 hr. A postprocedure head computed tomographic (CT) scan showed no evidence of stroke. The access site complication rate was 11% and included two instances of local hematoma formation, one pseudoaneurysm successfully treated with
thrombin injection, and two vessel thromboses distal to the sheath at access sites, one brachial and one femoral (Table III). Both were successfully treated with Fogarty catheter thrombectomy without negative sequelae. No embolic complications were identified. The 1-, 2-, and 3-year primary patency rates were 92 ± 5%, 84 ± 8%, and 77 ± 11%, respectively (Fig. 1). These rates reflect a total of five failed primary interventions over the period of follow-up. Of the two failed LCCA interventions, one occluded asymptomatically and was therefore not reintervened upon observation of adequate flow in the contralateral artery. The other LCCA underwent cryoplasty for asymptomatic in-stent restenosis recognized by duplex ultrasound at 2.3 years. Of two failed LSCA interventions, one failed due to inability to pass the guidewire at the time of intervention, while the other was found to have a blood pressure differential of 90 mm Hg at 1 month postintervention, despite having initial anatomical and hemodynamic success. This patient was not initially stented at the primary intervention due to vessel tortuosity and subsequently underwent carotidesubclavian bypass. The only failed primary BCA intervention was found to have in-stent restenosis at 1.3 years postintervention and was treated by balloon angioplasty at that time, before ultimately undergoing open surgical bypass at 3.8 years postintervention. This yielded 1-, 2-, and 3-year assisted primary patency rates of 95 ± 3%, 88 ± 8%, and 78 ± 11%, respectively. The 1-, 2-, and 3-year secondary patency rates were 95 ± 5%, 88 ± 8%, and 88 ± 8%, respectively (Figs. 2 and 3). Over the course of follow-up, symptom recurrence was noted in two of the 44 treated vessels (5%). This was comprised of one recurrence in the BCA group (13%) and one recurrence in the LSCA group (4%). Cox proportional hazards analysis was undertaken to investigate the impact of pre- and perioperative factors related to outcomes of primary, assisted primary, and secondary patencies. When analyzing across the patient cohort as a whole, no factor was significantly associated.
DISCUSSION The approach to supra-aortic trunk revascularization falls into three general categories: transthoracic, extrathoracic, and endovascular. Where advocated, the transthoracic approach is typically applied to major BCA disease or significant multivessel arch branch disease. It has demonstrated excellent longterm durability, with 10-year cumulative patency
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Fig. 1. Primary patency after percutaneous angioplasty and stenting of lesions of the noncoronary arch ostia. Hatched lines indicate where standard error exceeds 10%. Numbers at risk are shown in the table at the base of the figure.
Fig. 2. Assisted primary patency following repeat endovascular interventions for two of the total of five treatment failures. Hatched lines indicate where standard error exceeds 10%. Numbers at risk are shown in the table at the base of the figure.
rates in two of the largest series ranging 88-94%.3,4 In these series, Berguer et al.4 and Takach et al.3 reported operative mortality rates of 6% and 3%, respectively, and stroke rates of 10% and 3%, respectively. Additional morbidity included myocardial infarction, upper extremity swelling, pericardial tamponade, and sternal wound infection. Concern over these peri- and postoperative events has led many to utilize an extrathoracic, typically cervical, approach to manage patients with less extensive or single-vessel supra-aortic trunk disease or those with substantial comorbidities thought to make transthoracic repair prohibitively risky. In this setting, extrathoracic bypass has demonstrated 5-year cumulative patency ranging from 91-100% and 10year cumulative patency in the range 82-88%.5-8
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Fig. 3. Secondary patency following repeat endovascular intervention for reoccluded ostial lesion of the BCA. Hatched lines indicate where standard error exceeds 10%. Numbers at risk are shown in the table at the base of the figure.
Among two of the largest series of such patients, again by the groups Berguer et al.4 and Takach et al.3 but in separate publications from the aforementioned transthoracic data, operative mortality was 0.5% and 0.9%, respectively, while stroke rates were 3.8% and 1.3%, respectively. Additional morbidity included myocardial infarction, pulmonary complications, and graft infection; but the overall rate was less than in the case of transthoracic repair. In spite of this proven record for operative bypass in achieving superior long-term durability,3-8 percutaneous therapy for aortic arch branch disease has flourished, as it has in all vascular beds.9 This growth is related to certain inherent advantages over open surgical methods, including minimal invasiveness and avoidance of general anesthesia, leading to greater patient acceptance, among other reasons. Additionally, percutaneous therapy has been reported to produce lower costs, at least initially, when compared to open surgical therapy.7 We report outcomes on 44 patients undergoing endovascular treatment by way of balloon angioplasty (in 98%) and primary stenting (in 93%) of 45 ostial lesions of the aortic arch. In contrast to existing reports on percutaneous therapy for supraaortic branch disease, we chose to focus on ostial lesions out of concern that they may represent extension of aortic disease encroaching on the ostium with intervention outcomes that may differ from those of more distal disease, as is the case in renal ostial lesions.1,10,11 Ultimately, we achieved a 98% technical success rate with a cumulative patency rate of 88% at 3 years and a reintervention rate of 7% at an average of 2 years and 10 months clinical follow-up. These results are comparable
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with those reported to date for lesions encompassing all segments of the arch branches. Additionally, this level of patency was attained without any strokes or deaths within the postoperative period and with a low morbidity rate. Reports on endoluminal therapy for lesions of the supra-aortic branches began with balloon angioplasty and demonstrated rates of initial technical success ranging 88-100%, with some indication that rates were lower in the setting of occluded vessels relative to stenotic vessels.12-17 Cumulative patencies at around 3 years of follow-up were reported to range 86-98%, although one report including nine patients with occlusions reported a clinical success rate of 56% at a mean follow-up of 29 months.18 Subsequently, in the mid-1990s, reports of primary stenting began to emerge as aortic branch lesions were more aggressively pursued with endovascular therapy. Technical success rates again were high, ranging 92-100%.19-24 Bates et al.22 and Sullivan et al.,21 the largest such series to date, along with Takach et al.,7 have reported 3-year patency rates of 84-86%, all of which are in line with our own cumulative patency at 3 years of 88% after our initial technical success rate of 98%. These results suggest that stenting for ostial lesions yields results in line with stenting for lesions throughout the supra-aortic branches. It should be noted that, while others have reported differences in patency outcomes between the BCA and LSCA,24 we cannot make any such judgments because of our small number of patients (8) undergoing treatment of ostial innominate disease. In our series of 44 patients including 11 who underwent stenting of the LCCA, we encountered no periprocedural or postintervention strokes and one transient ischemic attack. In comparison, Takach et al.7 noted a stroke rate of 0%, while Sullivan et al.21 encountered two ischemic strokes (14%) among 14 patients undergoing common carotid artery intervention. It may be important to note that we, like Takach et al., utilized a transfemoral approach in treating common carotid artery lesions with one exception, while Sullivan et al. utilized a direct retrograde approach following neck incision and, in the two cases of stroke, performed bifurcation endarterectomy. It may be that direct manipulation of the carotid artery places the vessel at greater risk of ischemic events. Additionally, six of our LCCA interventions involved some form of distal embolic protection, while the remaining five, having been performed earlier in our experience, did not involve any attempt at distal protection. It is our current policy to employ a distal embolic protection device in all carotid interventions whenever
Endoluminal Therapy of Arch Ostial Disease 393
it can be safely achieved. However, one caveat must be made. This was a retrospective trial. Patients were not seen routinely postoperatively by a neurologist and did not undergo formal neurological evaluations. Self-reporting of neurological events can be three times lower than independently adjudicated events. By way of Cox proportional hazards analysis, we investigated the impact of all pre- and perioperative factors on treated vessel patency and survival and found no significant association with any of the factors studied. Notably, while some have found associations in outcomes with factors such as number of stents placed,2 low stent diameters,24 and hypothyroidism,22 we found no such significant association in our series. This is, however, not entirely surprising given the relatively small number of patients in this series. We conclude that our results support the continued use of percutaneous therapy to treat focal lesions of the BCA, LCCA, and LSCA, including those of the branch ostia. We do not find a decrease in initial or long-term patency or an increase in morbidity or mortality in treating solely ostial lesions relative to reports of more broadly based interventions of the supra-aortic branches. Furthermore, it retains a low morbidity and mortality rate, well below that published for open bypass procedures. REFERENCES 1. Baumgartner I, von Aesch K, Do DD, et al. Stent placement in ostial and nonostial atherosclerotic renal arterial stenoses: a prospective follow-up study. Radiology 2000;216:498-505. 2. Grundy SM, Brewer HB, Jr, Cleeman JI, et al.; for the Conference Participants. Definition of metabolic syndrome: report of the National Heart, Lung, and Blood Institute/ American Heart Association conference on scientific issues related to definition. Circulation 2004;109:433-438. 3. Takach TJ, Reul GJ, Cooley DA, et al. Brachiocephalic reconstruction I: operative and long-term results for complex disease. J Vasc Surg 2005;42:47-54. 4. Berguer R, Morasch MD, Kline RA. Transthoracic repair of innominate and common carotid artery disease: immediate and long-term outcome for 100 consecutive surgical reconstructions. J Vasc Surg 1998;27:34-42. 5. Fry WR, Jartin JD, Clagett GP, et al. Extrathoracic carotid reconstruction: the subclavian-carotid artery bypass. J Vasc Surg 1992;15:83-88. 6. Perler BA, Williams GM. Carotidesubclavian bypassda decade of experience. J Vasc Surg 1990;12:716-722. 7. Takach TJ, Duncan JM, Livesay JJ, et al. Brachiocephalic reconstruction II: operative and endovascular management of single-vessel disease. J Vasc Surg 2005;42:55-61. 8. Berguer R, Morasch MD, Kline RA, et al. Cervical reconstruction of the supra-aortic trunks: a 16-year experience. J Vasc Surg 1999;29:239-248. 9. Anderson PL, Gelijins A, Moskowitz A, et al. Understanding trends in inpatient surgical volume: vascular interventions, 1980-2000. J Vasc Surg 2004;39:1200-1208.
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