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Development of severe string sign in internal thoracic arterial graft during first month
Nobuaki Hirata1, Nobuaki Asaoka2, Akira Amemiya2
1Division of Cardiovascular Surgery, Takarazuka Municipal Hospital, Hyogo, Japan. hirata@xd5.so-net.ne.jp.
Insights
The string sign, a narrowing of the internal thoracic artery graft, was observed post-surgery. This finding, visualized with Doppler echocardiography, indicates graft compromise and potential blood flow reduction.
Area of Science:
- Cardiovascular Surgery
- Vascular Imaging
- Interventional Cardiology
Background:
- Internal thoracic artery grafts are crucial for coronary artery bypass grafting.
- Graft failure can lead to adverse cardiac events.
- Early detection of graft stenosis is vital for patient outcomes.
Purpose of the Study:
- To report a case of internal thoracic artery graft "string sign" development.
- To illustrate the utility of Doppler echocardiography in diagnosing graft stenosis.
- To highlight the progression of graft compromise.
Main Methods:
- Transthoracic Doppler echocardiography was used to monitor the internal thoracic artery graft post-surgery.
- Serial imaging assessed graft diameter and flow velocity.
- Coronary arteriography confirmed the graft morphology.
Main Results:
- A decrease in internal thoracic artery graft diameter was noted post-surgery.
- Flow velocity changes indicated progressive stenosis.
- Coronary arteriography confirmed severe "string sign" morphology on postoperative day 31.
Conclusions:
- The "string sign" can develop in internal thoracic artery grafts.
- Doppler echocardiography is effective in detecting and monitoring this complication.
- Early identification of graft stenosis is essential for timely intervention.
Abstract:
In the present case, development of the string sign in an internal thoracic arterial graft was observed using transthoracic Doppler echocardiography. Following surgery, the diameter of the internal thoracic graft decreased; however, the diameter of the left anterior descending coronary artery did not change from 1.9 mm. Further, the flow velocity in the internal thoracic artery during the systolic phase became greater than that in the early phase and then decreased on postoperative day 19, and it was not detected on postoperative day 31. Coronary arteriography performed on postoperative day 31 revealed a severely stringed internal thoracic artery.
