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Published on: June 28, 2019
Collateral Flow Reversal: Exploring Protective Role of Collateral Circulation in Acute Coronary Syndrome
Udit B Bhatnagar1,2, Gavin Nelson2, Adam Stys2
1Sanford Cardiovascular Institute, Sioux Falls, South Dakota.
Insights
Pre-existing collateral circulation may protect against severe heart attacks in acute coronary syndrome (ACS). This case study shows how robust collaterals mitigated damage during a myocardial infarction.
Area of Science:
- Cardiology
- Vascular Biology
- Interventional Cardiology
Background:
- The impact of pre-existing collateral circulation on acute coronary syndrome (ACS) presentation remains unclear.
- Collateral vessels can potentially supply blood flow to ischemic areas during coronary artery occlusion.
Abstract:
The effect of pre-existing collateral circulation on presentation of acute coronary syndrome (ACS) is not well known. We present a case of a 54-year-old male with a known history of chronic total occlusion of left circumflex artery and well-developed collaterals, who presented to the emergency department with non-STsegment elevation myocardial infarction. He underwent urgent coronary angiogram which showed an acute total thrombotic occlusion in proximal large right coronary artery with collaterals from left to right. After percutaneous coronary intervention, the collaterals reversed to a right to left direction. We postulate that the well-developed collateral circulation protected the patient from larger transmural ischemia and ST elevation myocardial infarction.
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