Skip to Main Content

KEY FEATURES

ESSENTIALS OF DIAGNOSIS

  • Post–coronary artery bypass grafting (CABG) using an internal thoracic artery pedicle graft

  • Angina with unilateral arm exercise

  • Subclavian artery stenosis demonstrated by imaging, proximal to the internal thoracic artery used for the coronary graft in the affected upper limb

GENERAL CONSIDERATIONS

  • The internal thoracic artery is the preferred conduit for proximal left anterior descending CABG because of its relative resistance to atherosclerosis and demonstrated excellent long-term patency

  • Unfortunately, the subclavian artery, from which the internal thoracic is a branch, is a common site of atherosclerotic plaque build-up

  • When the subclavian is obstructed proximal to the origin of the internal thoracic, coronary blood flow can be compromised, especially during arm exercise (coronary steal)

CLINICAL PRESENTATION

SYMPTOMS AND SIGNS

  • Angina pectoris with unilateral arm exercise

  • Vertebrobasilar symptoms with unilateral arm exercise

PHYSICAL EXAM FINDINGS

  • > 20 mm Hg difference in systolic blood pressure between right and left arm

  • Reduced pulse in affected arm

DIFFERENTIAL DIAGNOSIS

  • Progressive native coronary artery disease

  • Technical problems with the internal thoracic artery graft

  • Disease in vein grafts to other coronary arteries

DIAGNOSTIC EVALUATION

ELECTROCARDIOGRAPHY

  • ST-T changes of ischemia

IMAGING STUDIES

  • Stress myocardial imaging demonstrates ischemia

DIAGNOSTIC PROCEDURES

  • Catheterization and angiography demonstrate the subclavian obstruction proximal to the internal thoracic artery origin

TREATMENT

CARDIOLOGY REFERRAL

  • Recurrent angina after bypass surgery

HOSPITALIZATION CRITERIA

  • Acute coronary syndrome

  • Significant resting arm ischemia (rare)

MEDICATIONS

  • Standard antianginal drugs

THERAPEUTIC PROCEDURES

  • Angioplasty and stenting of the subclavian artery

SURGERY

  • Extrathoracic surgical approach:

    • – Conduit from carotid to the subclavian distal to the stenosis or distal subclavian to carotid anastomosis

  • Intrathoracic surgical approach:

    • – Subclavian endarterectomy or aortosubclavian grafting

MONITORING

  • ECG monitoring in hospital as appropriate

DIET AND ACTIVITY

  • Restrict arm exercise until problem corrected

  • Low-fat diet

ONGOING MANAGEMENT

HOSPITAL DISCHARGE CRITERIA

  • Resolution of symptoms

  • After successful procedure or surgery

FOLLOW-UP

  • Three months, 6 months, then yearly if stable

COMPLICATIONS

  • Ischemic digits due to emboli

  • Myocardial infarction

PROGNOSIS

  • Good, with correction of subclavian stenosis

PREVENTION

  • Because the incidence of significant asymptomatic subclavian artery disease is low (< 5%), routine angiography of this vessel at the time of cardiac catheterization is not recommended

  • The blood pressure ...

Pop-up div Successfully Displayed

This div only appears when the trigger link is hovered over. Otherwise it is hidden from view.