Coronary subclavian steal from a left internal thoracic artery coronary bypass graft due to ipsilateral subclavian artery stenosis and an arteriovenous graft in a hemodialysis patient with left vertebral artery occlusion

Impact of coronary-subclavian steal after surgical myocardial revascularization with internal thoracic artery in chronic hemodialysis patients: A meta-analysis

Patients in hemodialysis with an arm arteriovenous fistula undergoing coronary artery bypass grafting (CABG) with an internal thoracic artery have been reported to suffer from coronary-subclavian steal (CSS) during dialysis session. However, its occurrence is still debated. A systematic literature review was performed to identify all studies investigating the occurrence of a CSS event in this subset of patients. The primary endpoint was the analysis of CSS and the following early and late survival outcomes. Independent determinants of CSS and the impact of the distance between the arteriovenous fistula (upper arm vs forearm) and the ipsilateral internal thoracic artery graft on CSS events and mortality were studied. Early and late survival outcomes were analyzed by comparing ipsilateral versus contralateral arteriovenous fistula. Of the 1,383 retrieved articles, 10 were included (n = 643 patients). The pooled event rate of CSS was 6.46% [95%CI=2.10-18.15], while of symptomatic CSS incidence was 3.99% [95%CI=0.95-15.25]. No survival differences were noted when comparing ipsilateral to contralateral arteriovenous fistula-internal thoracic artery combinations. On meta-regression, the upper arm was associated with more CSS events, while the forearm to lower late mortality rates. Independently from arteriovenous fistula-internal thoracic artery combination, CSS was not associated to higher mortality rates. Particular attention is warranted when selecting the type of conduits for CABG in patients with an arteriovenous fistula or if highly expected to need one in the near future after surgery. A contralateral arteriovenous fistula-internal thoracic artery combination is preferable. If this is not possible, a forearm arteriovenous fistula position should be preferred.

Coronary-subclavian steal syndrome causing myocardial infarction after arteriovenous fistula creation: a case report

Coronary subclavian steal syndrome (CSSS) caused by left subclavian artery (LSA) stenosis is a rare cause of myocardial infarction in patients having coronary artery bypass grafting (CABG), and it has also been observed after an arteriovenous fistula (AVF) was made. A 79-year-old woman who had undergone CABG years earlier and an AVF creation 1 month before experienced a non-ST-elevation myocardial infarction (NSTEMI). While selective catheterization of the left internal thoracic artery graft was impossible, a computed tomography scanner showed patency of all bypasses and proximal subocclusive LSA stenosis, and the digital blood pressure measurements objectified a haemodialysis-induced distal ischaemia. LSA's angioplasty and covered stent placement were successfully performed, resulting in symptom remission. A CSSS-induced NSTEMI due to a LSA stenosis aggravated by a homolateral AVF several years after CABG has been documented only infrequently. If vascular access is required in the presence of CSSS risk factors, the contralateral upper limb should be preferred.

An Interesting Observation Regarding Retrograde Vertebral Artery Flow in Patients With Dialysis Access Fistulas

OBJECTIVES

Retrograde vertebral artery flow, the steal phenomenon, is most frequently caused by a flow-limiting stenosis of the proximal subclavian artery. The reversal of flow can be incomplete, resulting in bidirectional flow: retrograde in systole and antegrade in diastole. Less often, retrograde vertebral artery flow is the consequence of increased subclavian flow, as might occur with a well-functioning dialysis access fistula. Our objective was to evaluate bidirectional vertebral artery flow associated with dialysis access fistulas.

METHODS

We retrospectively reviewed the direction of flow through the vertebral artery in systole and diastole of 335 patients with dialysis fistulas who had undergone extracranial cerebral vascular Doppler examinations.

RESULTS

Fifteen patients had retrograde flow in their vertebral artery ipsilateral with the side of their fistula. There was completely reversed flow in 1 patient and bidirectional flow in the other 14. For each of these 14, the flow was antegrade in early systole and retrograde in diastole. Compression of the fistula restored the antegrade flow.

CONCLUSIONS

Under conditions of reduced subclavian artery flow, bidirectional vertebral artery flow will be retrograde in early systole and antegrade in diastole. Under conditions of increased subclavian artery flow, bidirectional flow through the vertebral artery will be antegrade in early systole and retrograde in diastole.