Atherectomy of the subclavian artery for patients with symptomatic coronary-subclavian steal syndrome

Subclavian atherectomy and angioplasty for coronary subclavian steal syndrome post CABG

Coronary subclavian steal syndrome is an uncommon complication occurring in patients with coronary artery bypass graft (CABG). We describe a case of a 69-year-old male with a remote history of CABG who presented with exertional left arm pain and angina. Computed Tomographic Angiography of the chest demonstrated a severe left proximal subclavian artery stenosis. The case demonstrates successful application of subclavian atherectomy with use of embolic protective device, alleviating the need of stent, for treatment of Coronary subclavian steal syndrome in patient with remote history of CABG.

Review of coronary subclavian steal syndrome

The clinical benefits of using the left internal mammary artery (LIMA) to bypass the left anterior descending artery are well established making it the most frequently used conduit for coronary artery bypass surgery (CABG). Coronary subclavian steal syndrome (CSSS) occurs during left arm exertion when (1) the LIMA is used during bypass surgery and (2) there is a high grade (≥75%) left subclavian artery stenosis or occlusion proximal to the ostia of the LIMA resulting in "stealing" of the myocardial blood supply via retrograde flow up the LIMA graft to maintain left upper extremity perfusion. Although CSSS was once thought to be a rare phenomenon, its prevalence has been underestimated and is becoming increasingly recognized as a serious threat to the success of CABG. Current guidelines are lacking on recommendations for screening of subclavian artery stenosis (SAS) pre- and post-CABG. We hope to provide an algorithm for SAS screening to prevent CSSS in internal mammary artery bypass recipients and review treatment options in the percutaneous era.

Subclavian Stent Implantation to Alleviate Coronary Steal through a Patent Internal Mammary Artery Graft

Purpose:

Interventional techniques are rapidly supplanting conventional surgical therapies for the treatment of brachiocephalic occlusive disease. Although coronary-subclavian steal has been successfully alleviated with subclavian angioplasty, we report the first use of a Palmaz stent in the left subclavian artery (SCA) of a patient with a compromised left internal mammary artery (IMA) graft.

Methods and Results:

A 65-year-old male patient had undergone triple coronary artery bypass grafting in 1992, but 6 months later, severe narrowing occurred in two of the saphenous vein grafts, and arteriography identified a high-grade stenosis in the SCA supplying the left IMA graft to the left anterior descending coronary artery. Following balloon dilation of one saphenous vein graft stenosis, the left SCA was stented primarily with a P3008 Palmaz stent. Normal hemodynamics were restored, and the patient has been free of coronary steal symptoms for over 1 year.

Conclusion:

This case illustrates yet another aspect to the usefulness of intravascular stents in restoring and maintaining in flow to bypass grafts.

Coronary subclavian steal syndrome

PURPOSE OF REVIEW

Coronary subclavian steal syndrome (CSSS) is the reversal of blood flow in an internal mammary artery bypass graft that results in coronary ischemia. CSSS is an uncommon but treatable cause of coronary ischemia. In this review, we highlight the historical background and epidemiology of CSSS, common clinical presentations, diagnosis of CSSS and management strategies for relieving ischemia. We also present a case report to illustrate the complexity of CSSS and percutaneous management using current technology.

RECENT FINDINGS

Most commonly, CSSS results from atherosclerotic stenosis of the subclavian artery and occurs in 2.5-4.5% of patients referred for coronary artery bypass grafting (CABG). All patients referred for CABG should have bilateral noninvasive brachial blood pressures checked to screen for the underlying subclavian stenosis. A review of 98 case reports with 128 patients demonstrated a diverse clinical presentation of CSSS, including acute myocardial infarction, unstable angina and acute systolic heart failure. Resolution of CSSS symptoms has been reported with both surgical and percutaneous revascularization. Long-term patency with either revascularization strategy is excellent. Percutaneous revascularization is largely considered the first-line therapy for CSSS and can be safely performed prior to CABG to prevent CSSS.

SUMMARY

CSSS should be suspected in patients presenting with angina, heart failure or myocardial infarction after CABG. Successful amelioration of CSSS symptoms can be safely and effectively performed via percutaneous revascularization.

Evaluation of coronary subclavian steal syndrome using sestamibi imaging and duplex scanning with observed vertebral subclavian steal

Coronary subclavian steal is defined as retrograde blood flow from the myocardium through the internal mammary artery graft, secondary to a proximal subclavian artery stenosis. The incidence of this syndrome in patients undergoing internal mammary artery grafts for coronary artery bypass is estimated to be 0.44%. Angiography remains the definitive diagnostic test for confirming this condition. We describe a noninvasive method for evaluating coronary subclavian steal syndrome in a 57-year-old man, with a 50-55% subclavian stenosis confirmed by angiography. Noninvasive evaluation using duplex scanning demonstrated normal vertebral artery blood flow. Technetium 99m-sestamibi (99mTc) imaging confirmed a fixed anterolateral defect. When left-arm isometric exercise was employed, retrograde vertebral artery blood flow was observed by Doppler imaging. A repeat 99mTc-sestamibi study documented an increase in tracer distribution in the anterolateral defect confirming reperfusion of the myocardium through the left internal mammary artery graft. The use of duplex scanning and 99mTc-sestamibi may serve as an adjunct in evaluating coronary subclavian steal syndrome as well as documenting transient vertebral subclavian steal in this patient population.

Myocardial thievery: the coronary-subclavian steal syndrome

Coronary-subclavian steal syndrome entails the reversal of blood flow in a previously constructed internal mammary artery coronary conduit, which produces myocardial ischemia. The most frequent cause of the syndrome is atherosclerotic disease in the ipsilateral, proximal subclavian artery. Although coronary-subclavian steal was initially reported to be rare, the increasing documentation of this phenomenon and its potentially catastrophic consequences in recent series suggests that the incidence of the problem has been underreported and that its clinical impact has been underestimated. We review the causes and background of coronary-subclavian steal; methods of preventing, diagnosing, and treating it; and the potential influence of various treatment regimens on long-term survival and the likelihood of late adverse events in patients with coronary-subclavian steal syndrome.

Concomitant Brachiocephalic and Coronary Artery Disease: Outcome and Decision Analysis

BACKGROUND

In patients with coronary artery disease, concomitant brachiocephalic disease may affect outcome and influence decision making regarding operative staging, technique, and choice of conduit.

METHODS

Eighty consecutive patients (mean age, 59.3 years; 60.0% male) with concomitant brachiocephalic and coronary artery disease were identified either before (group A, n = 48) or after (group B, n = 32) coronary artery bypass grafting. Patients who had symptomatic brachiocephalic and coronary artery disease before surgery underwent concomitant brachiocephalic reconstruction and coronary artery bypass grafting using either all-vein coronary conduits (n = 41) or vein-and-internal mammary artery conduits (n = 7). Patients who had coronary-subclavian steal syndrome after coronary artery bypass (group B, n = 32) underwent either surgical (n = 5) or endovascular (n = 27) brachiocephalic reconstruction only.

RESULTS

All patients were asymptomatic after intervention. Operative mortality was 4.2% for group A and 3.1% for group B. The perioperative stroke rate was 2.1% for group A and 0% for group B. Actuarial 10-year freedom from specific events for group A was as follows: death 59.9 +/- 12.8%, brachiocephalic restenosis 100%, coronary-subclavian steal syndrome 100%, myocardial infarction 83.5 +/- 10.5%, stroke 82.1 +/- 9.9%, redo coronary artery bypass grafting 95.8 +/- 4.1%, other vascular operation 82.2 +/- 8.9%, and adverse cardiac outcome (death, redo coronary artery bypass grafting, or myocardial infarction) 52.9% +/- 13.2% (for patients with all-vein conduits) or 100% (for patients with vein-and-internal mammary artery conduits). At midterm follow-up (mean, 2.92 years), both the surgical and the endovascular treatment subgroups of group B had 100% brachiocephalic patency.

CONCLUSIONS

Long-term results in a limited population support continued evaluation of concomitant brachiocephalic reconstruction and coronary artery bypass grafting with use of the internal mammary artery conduit in an attempt to improve late survival in patients with concomitant disease. The excellent midterm brachiocephalic patency after either surgical or endovascular treatment of patients with coronary-subclavian steal syndrome supports continued evaluation of both methods.

Coronary subclavian steal syndrome: non-invasive imaging and percutaneous repair

Although coronary subclavian steal syndrome (CSSS) is relatively uncommon, it is a well documented cause of graft failure in patients having undergone coronary artery bypass grafting (CABG) using the left internal mammary artery (LIMA). Here we report a case of CSSS induced by restenosis of a left subclavian artery (SCA) origin stent, identified by increased velocities within the stent and an abnormal ipsilateral vertebral artery (VA) waveform on Duplex ultrasound imaging. This was successfully treated percutaneously by re-stenting, resulting in restoration of normal SCA waveforms and velocities, and normalization of the ipsilateral VA waveform.

Ultrasound of the extracranial vertebral artery

Ultrasound of the extracranial vertebral artery (VA) is a valuable technique. This review outlines VA anatomy and the technical aspects of ultrasound scanning of the VA, then proceeds to demonstrate and discuss the use of ultrasound of the VA in identifying vertebral-subclavian and coronary-subclavian steal syndromes, aortic valve disease, stenosis or occlusion of the VA itself, dissection and aneurysm of the VA, and vertebrobasilar insufficiency.

Angioplasty of an asymptomatic total occlusion of the left subclavian artery to provide access for coronary angiography and intervention: A case report

Reports and follow-up of angioplasty and stenting of asymptomatic totally occluded subclavian arteries are limited. We present a case of unstable angina and arterial occlusion of all four extremities treated with subclavian angioplasty and stenting with subsequent coronary angiography and percutaneous coronary intervention. Twelve-month follow-up is also provided.

Percutaneous angioplasty and stenting of left subclavian artery stenosis in patients with left internal mammary-coronary bypass grafts: clinical experience and long-term follow-up

The authors report their experience with percutaneous transluminal angioplasty (PTA) and stenting of the left subclavian artery (LSA) in patients with recurrent angina and a left internal mammary (LIMA)-coronary bypass graft or in patients who will be undergoing LIMA-coronary artery bypass grafting. From November 1990 to February 2001, 21 patients (11 men and 10 women) with significant left subclavian artery stenosis were treated; 18 patients had a prior LIMA bypass graft, and 3 patients were treated before coronary artery bypass surgery. Angiographic follow-up was performed in 12 patients and clinical follow-up was obtained in all patients. All lesions were atherosclerotic in etiology and located in the proximal left subclavian artery. The mean stenosis was 81% (range 50-100%). All patients initially underwent PTA. Stents were placed in 7 patients for suboptimal PTA results. Technical success was achieved in all patients. Pressure gradient measurements were available in 6 patients. Mean pretreatment gradient was 29 mm Hg (range, 10-50 mm Hg) and fell to 3 mm Hg (0-8 mm Hg) posttreatment. There were 2 minor and 2 major complications. The 30-day mortality rate was 9.5% (2 patients). The remaining 19 patients had clinical or angiographic follow-up of 4-68 months (mean, 27 months). Three patients were found to have recurrent stenoses by angiography 8-43 months after PTA and 3 more had clinical signs of recurrent stenosis. Therefore, the long-term clinical patency rate of LSA PTA and stent was 15 of 19 (79%). One was managed with bypass surgery, 1 with repeat PTA and stent placement, and 1 was managed conservatively. Therefore, the assisted patency was 15 of 19 (79%). Eleven of 19 (58%) of the patients in long-term follow-up had cardiac symptoms, but repeat angiography excluded recurrent LSA stenosis as the cause of their symptoms in 7 cases. Only 4/19 (21%) had cardiac symptoms potentially attributable to LSA restenosis. Four patients expired during follow-up, but 3 had no evidence of subclavian stenosis. PTA and stenting is an effective treatment of proximal left subclavian artery stenosis in patients who develop angina after a LIMA-coronary artery bypass, or in patients before a LIMA-CABG. Cardiac symptoms after LSA PTA and stent are most often due to progressive coronary artery disease rather than to recurrent LSA stenosis.

Surgical treatment of coronary subclavian steal syndrome with carotid subclavian bypass

Coronary subclavian steal syndrome (CSS) results from proximal subclavian artery occlusive disease causing reversal of flow in an internal mammary artery used as conduit for coronary artery bypass leading to myocardial ischemia. Although percutaneous transluminal angioplasty and stent (PTAS) for subclavian lesions has been successful, it is not always feasible. In this study, the results of carotid subclavian bypass (CSB) for symptomatic CSS due to subclavian occlusion and stenosis not amenable to PTAS were analyzed. The records of patients undergoing CSB for CSS between 1991 and 2001 were reviewed. Patients with lesions not amenable to angioplasty or stent were selected for CSB. Degree of preoperative myocardial ischemia was stratified according to New York Heart Association classification. Graft patency was analyzed by life-table methods. Our results showed that CSB for treatment of symptomatic CSS can be performed safely with excellent mid-term durability. In the setting of proximal subclavian artery disease not amenable to PTAS, CSB provides an acceptable means of treatment for symptomatic CSS.

Percutaneous Transluminal Angioplasty and Stent Placement for Subclavian Steal Syndrome With Concomitant Anterograde Flow in the Left Internal Mammary Artery Graft for Coronary Artery Bypass-Case Report-

A 63-year-old man presented with subclavian steal syndrome associated with left internal mammary artery (IMA) bypass graft to a coronary artery. He was admitted with a history of oppressive sensation in the chest, dizziness, and light headedness on exertion for 2 weeks in March 2002. He had undergone myocardial revascularization consisting of a left IMA-to-left anterior descending coronary artery graft in April 1988. His blood pressure was 140/70 mmHg in the right arm and 80/64 mmHg in the left arm. Aortic arch arteriography revealed complete occlusion of the left subclavian artery proximal to the left IMA takeoff and subclavian steal with anterograde flow of the left IMA. Percutaneous angioplasty and stent placement with protection of the left IMA bypass graft using a balloon catheter was successfully performed without complication by cerebral or myocardial ischemia. Complete recanalization of the occluded left subclavian artery and anterograde flow of the left vertebral artery were achieved. His symptoms disappeared and blood pressure in the left arm recovered. This variant of coronary subclavian steal might require protection of the left IMA during angioplasty and stent placement.

Restenting for subclavian in-stent restenosis with symptomatic recurrent coronary-subclavian steal

PURPOSE

To determine whether restenting for recurrent coronary-subclavian syndrome is technically feasible, provides durable results, and is a reasonable alternative to surgery.

CASE REPORT

A 58-year-old woman with a left internal mammary artery (LIMA) bypass to the left anterior descending artery underwent angioplasty and stent placement for left subclavian stenosis and coronary-subclavian steal. Twenty-three months later, she returned with progressive angina and left arm claudication; heart catheterization demonstrated restenosis of the subclavian artery at the stent site with recurrence of the coronary-subclavian steal. Successful redo angioplasty and stenting resulted in normal antegrade flow through the LIMA graft. The patient has remained asymptomatic for 3 years without evidence of recurrent in-stent stenosis on serial noninvasive studies.

CONCLUSIONS

Restenting is technically feasible and appears to be a durable response to subclavian in-stent restenosis in patients with coronary subclavian steal.

Incidence of coronary-subclavian steal syndrome in patients undergoing noncardiac surgery

OBJECTIVE

To identify the incidence of coronary-subclavian steal syndrome in patients undergoing noncardiac surgery.

DESIGN

Prospective.

SETTING

Veterans Affairs Medical Center and university-affiliated medical center.

PARTICIPANTS

Adult patients with prior coronary artery bypass graft surgery and documented use of an internal mammary artery.

INTERVENTIONS

Bilateral simultaneous brachial blood pressures were determined noninvasively. The presumptive diagnosis of ipsilateral subclavian artery stenosis and coronary-subclavian steal syndrome was made if the systolic blood pressure differential was >20 mmHg.

MEASUREMENTS AND MAIN RESULTS

The presumptive diagnosis of ipsilateral subclavian artery stenosis based on a blood pressure differential was made in 6 of 86 (5%) patients screened. The diagnosis of coronary-subclavian steal syndrome was confirmed at cardiac catheterization by observing retrograde internal mammary artery flow in 3 patients or lack of internal mammary artery flow in 1 patient (3.4%). All 4 patients with angiographic confirmation had either angina or silent ischemia. Three patients had successful carotid subclavian bypass, and 1 patient refused surgery. Two patients had no evidence of myocardial ischemia and underwent their planned procedure without incident.

CONCLUSION

Coronary-subclavian steal syndrome occurs with relative frequency in noncardiac surgery patients with prior coronary artery bypass graft surgery using internal mammary artery conduits. Bilateral blood pressure measurements should be routinely performed during the preoperative evaluation. A pressure differential >20 mmHg should suggest the possibility of coronary-subclavian steal syndrome.

Concomitant subclavian and coronary artery disease

BACKGROUND

Proximal subclavian artery occlusive disease in the presence of a patent internal mammary artery used as a conduit for a coronary artery bypass graft procedure may cause reversal of internal mammary artery flow (coronary-subclavian steal) and produce myocardial ischemia.

METHODS

We reviewed outcome to determine whether subclavian artery revascularization can provide effective protection from and treatment for coronary-subclavian steal. Between 1985 and 1997, 20 patients had either concomitant subclavian and coronary artery disease diagnosed before operation (group 1, 5 patients) or symptomatic coronary-subclavian steal occurring after a previous coronary artery bypass graft procedure (group 2, 15 patients). Patients in group 1 received direct subclavian artery bypass and a simultaneous coronary artery bypass graft procedure in which the ipsilateral internal mammary artery was used for at least one of the bypass conduits. Patients in group 2 received either extrathoracic subclavian-carotid bypass (5 patients, 33.3%) or percutaneous transluminal angioplasty and stenting (10 patients, 66.7%) as treatment for symptomatic coronary-subclavian steal.

RESULTS

All patients were symptom-free after intervention. One patient treated with percutaneous transluminal angioplasty and stenting died of progressive renal failure. Follow-up totaled 58.5 patient-years (mean, 3.1 years/patient). In group 1, primary patency was 100% (mean follow-up, 3.7 years). In group 2, one late recurrence was treated by operative revision, yielding a secondary patency rate of 100% (mean follow-up, 2.9 years).

CONCLUSIONS

Subclavian artery revascularization can provide effective protection from and treatment for coronary-subclavian steal with acceptably low operative risk. Midterm follow-up demonstrates good patency.

[Angina caused by subclavian-coronary steal in patients revascularized with internal mammary artery]

After coronary bypass surgery in the left internal mammary artery, occlusive atherosclerosis in the proximal subclavian artery can produce reverse flow in the mammary artery and myocardial ischemia (coronary-subclavian steal syndrome). This is a rare cause of recurrent myocardial ischemia. We present two patients with postoperative complete obstruction in the proximal subclavian artery and inverse flow in the mammary artery producing severe ischemia in the left anterior descending artery territory. Both patients were treated with subclavian-subclavian bypass, which in one patient was ineffective in producing an adequate anterograde flow in the left internal mammary artery. We review clinical management, diagnostic methods and therapeutic options used in the coronary-subclavian steal syndrome.

Concomitant occlusive disease of the coronary arteries and great vessels

BACKGROUND

Although an increasing number of elderly and high-risk patients, including those with generalized atherosclerosis, are undergoing coronary revascularization, few reports exist regarding the management of patients who have both occlusive disease of the great vessels and coronary artery disease.

METHODS

Between 1972 and 1996, 31 consecutive patients (mean age, 56.5 years; 74% men) with multivessel coronary artery disease and symptomatic occlusive disease of the great vessels (25 single-vessel, 80.6%; 6 multiple-vessel, 19.4%) had 40 great vessels reconstructed by transthoracic bypass (n = 17, 42.5%), transthoracic endarterectomy (n = 8, 20%), or extrathoracic bypass (n = 15, 37.5%). All patients had simultaneous coronary artery bypass grafting (mean, 2.6 grafts per patient), and 8 patients had 10 distal carotid bifurcation endarterectomies (6 staged, 4 simultaneous).

RESULTS

The early primary patency rate was 100%, and symptoms resolved completely in all 31 patients. There was 1 in-hospital death (3.2%) in a patient who had a respiratory arrest 11 days after operation. Perioperative morbidity included two myocardial infarctions (6.5%) and one opposite-hemisphere, embolic stroke (3.2%). Long-term follow-up of the 30 survivors (167.4 patient-years; mean, 5.6 years per patient) documented 5- and 10-year actuarial survival rates of 88.6% and 60.4%, respectively, with a 100% late brachiocephalic primary patency rate. Ten-year actuarial rates of freedom from the following events were as follows: death, 60.4%; myocardial infarction, 82.5%; stroke, 90.9%; percutaneous transluminal coronary angioplasty or redo coronary artery bypass grafting, 95.2%; and vascular operation or amputation, 78.4%.

CONCLUSIONS

Depending on the anatomic distribution of the disease, an integrated approach to great vessel reconstruction that incorporated transthoracic and extrathoracic approaches and techniques of endarterectomy and bypass resulted in few adverse outcomes and excellent long-term patency. Simultaneous revascularization of the great vessels and coronary arteries can produce immediate and long-term, symptom-free outcome with acceptably low operative risk.

Concomitant cerebral and coronary subclavian steal

We report the unusual presentation of simultaneous coronary and cerebrovascular insufficiency secondary to subclavian steal in a patient previously treated with coronary artery bypass grafting. Movement of the arm produced reversal of flow ("steal") in both the left vertebral and left internal thoracic arteries and resulted in the onset of angina and neurologic symptoms.

Coronary subclavian steal syndrome following coronary by-pass surgery

The coronary steal syndrome is an uncommon but well recognised occurrence following coronary artery by-pass surgery using the internal mammary artery. We report a case of coronary steal successfully treated with percutaneous transluminal angioplasty of a subclavian stenosis.

Percutaneous transluminal stent placement to treat subclavian steal syndrome

PURPOSE

To describe nonsurgical stent placement to treat subclavian steal syndrome after failure of traditional balloon angioplasty.

PATIENTS AND METHODS

Seven patients with subclavian steal syndrome underwent diagnostic angiography, which showed four stenoses and three occlusions of the proximal left subclavian artery. Most patients presented with vertigo, left arm claudication, or syncope. Initial balloon angioplasty failed; there was elastic recoil with more than 30% residual stenosis or subintimal dissection. The three occlusions were treated with urokinase pulse-spray thrombolysis. All seven patients then underwent stent placement.

RESULTS

Initial technical success was achieved in all seven cases (100%), with an average right versus left arm blood pressure gradient of 0 mm Hg (-11 to 12 mm Hg) at mean follow-up of 12 months (4-24 months) (positive gradient = systolic pressure of right arm > that of left arm; negative gradient = systolic pressure of left arm > that of right arm). Symptoms of arm claudication and syncope resolved, and vertigo improved or resolved after the procedure. There were no deaths, strokes, or emboli in the perioperative or follow-up period.

CONCLUSION

Percutaneous transluminal stent placement may be an effective treatment of subclavian steal syndrome in patients with lesions that are refractory to traditional angioplasty.

Coronary subclavian steal: a recurrent case with notes on detecting the threat potential

A 43-year-old military patient with silent myocardial ischemia due to proximal anterior descending coronary artery and major diagonal branch stenoses had left and right internal mammary artery grafts in 1973, with excellent angiographic results. In 1984, silent ischemia recurred, due to proximal subclavian occlusion with collateral subclavian steal from the left internal mammary artery. A carotid-subclavian artery graft required replacement in 1987 and in 1989 for steal recurrence from graft stenosis due to thrombosis/atherosclerosis. The final 12-mm graft remained smooth with conventional anticoagulant therapy. However, in 1994, ostial compromise of the left internal mammary artery reduced flow enough to require relief of the original and unchanged anterior descending stenosis by transluminal angioplasty and stent placement. Observations are made on subclavian steal and simple methods for detecting its potential for occurrence.

Subclavian stent implantation to alleviate coronary steal through a patent internal mammary artery graft

PURPOSE

Interventional techniques are rapidly supplanting conventional surgical therapies for the treatment of brachiocephalic occlusive disease. Although coronary-subclavian steal has been successfully alleviated with subclavian angioplasty, we report the first use of a Palmaz stent in the left subclavian artery (SCA) of a patient with a compromised left internal mammary artery (IMA) graft.

METHODS AND RESULTS

A 65-year old male patient had undergone triple coronary artery bypass grafting in 1992, but 6 months later, severe narrowing occurred in two of the saphenous vein grafts, and arteriography identified a high-grade stenosis in the SCA supplying the left IMA graft to the left anterior descending coronary artery. Following balloon dilation of one saphenous vein graft stenosis, the left SCA was stented primarily with a P3008 Palmaz stent. Normal hemodynamics were restored, and the patient has been free of coronary steal symptoms for over 1 year.

CONCLUSION

This case illustrates yet another aspect to the usefulness of intravascular stents in restoring and maintaining inflow to bypass grafts.

Use of angioplasty in the prevention and treatment of coronary--subclavian steal syndrome

PURPOSE

The coronary-subclavian artery steal (CSS) syndrome is caused by critical stenosis in the subclavian artery proximal to a bypass graft from the internal mammary artery (IMA) to the coronary artery. The stenosis results in retrograde flow in the IMA and steal from the coronary artery.

PATIENTS AND METHODS

Percutaneous transluminal angioplasty (PTA) was performed in eight patients (five men, three women). In four patients (group 1), coronary ischemia had developed 0.5-70 months (mean, 31 months) after IMA-to-coronary artery bypass surgery. These four patients (mean age, 58 years; range, 44-68 years) underwent PTA of a single area of focal subclavian stenosis to treat CSS. In four other patients (group 2), atherosclerotic subclavian stenosis had developed proximal to a donor IMA before planned bypass surgery. These patients (mean age, 53 years; range, 50-57 years) underwent PTA of a single focal subclavian stenosis to prevent CSS.

RESULTS

Group 1 patients were free of myocardial ischemia at follow-up (mean follow-up, 39.0 months; range, 14-101 months). Three of four patients in group 2 underwent coronary artery bypass grafting with the ipsilateral IMA following PTA of the subclavian stenosis; they were free of angina at follow-up (mean follow-up, 14 months; range, 10-18 months).

CONCLUSION

PTA is a safe and efficacious short-term method for prevention and treatment of CSS syndrome.

Coronary-subclavian steal syndrome: report of five cases

The internal mammary artery (IMA) is the conduit of choice for cardiac revascularization. The phenomenon of retrograde flow in this graft secondary to proximal subclavian artery stenosis is an infrequent but increasingly recognized clinical entity and has been termed the "coronary-subclavian steal syndrome." We report on five patients with this syndrome. All were men. The average age was 65 years (range 56 to 68 years). The mean interval from coronary bypass to presentation was 7.8 years (range 1 month to 18 years). Three patients presented with unstable angina and one with congestive heart failure. One patient was asymptomatic from a cardiac standpoint. The mean arm systolic blood pressure differential was 45 mm Hg (range 30 to 60 mm Hg). Each patient underwent cardiac catheterization, and retrograde IMA flow was demonstrated in 100%. Arteriography confirmed the presence of a proximal high-grade (> 75%) subclavian stenosis in all patients. Stress thallium scanning was performed in two patients and demonstrated anterolateral ischemia in both. Operative intervention in four patients consisted of a left carotid-subclavian bypass using an 8 mm synthetic graft. There was no perioperative morbidity or mortality. Postoperative thallium scanning revealed resolution of the ischemic process. The average length of follow-up was 20 months (range 12 to 25 months) with all patients remaining asymptomatic. The one patient who refused surgery died at 12 months. When IMA grafting is contemplated, proximal subclavian stenosis should be suspected if there is > 20 mm Hg systolic pressure differential between the arms.(ABSTRACT TRUNCATED AT 250 WORDS)

Endoluminal stenting of a subclavian artery stenosis to treat ischemia in the distribution of a patent left internal mammary graft

Subclavian artery stenosis is a rare cause of recurrent myocardial ischemia in patients who have undergone left internal mammary-coronary artery bypass grafting. A patient with this syndrome was successfully treated by placement of Palmaz biliary stents in the left subclavian artery. Angiographic and hemodynamic evidence of restricted subclavian flow resolved following stenting, as did the patient's unstable angina syndrome. Endoluminal stenting of the proximal subclavian artery for the treatment of coronary-subclavian steal can be performed safely and provides an alternative to other forms of surgical or percutaneous (PTCA, directional atherectomy) revascularization for treatment of this disorder.

Angiographic evaluation of a carotid-subclavian bypass graft in a patient with subclavian artery stenosis and left internal mammary artery bypass graft

The incidence of coronary subclavian steal syndrome is estimated to be 0.4%. When revascularization is necessary, the preferred technique is the carotid-subclavian bypass graft. Failure of a carotid-subclavian graft is rare. We present a patient with subclavian stenosis who required reevaluation of both the carotid subclavian conduit and the left internal mammary bypass graft. A combined femoral and left brachial approach is recommended for evaluating the carotid-subclavian graft and left internal mammary artery graft in patients with bypassed subclavian artery stenosis and prior myocardial revascularization.