Failure of drug-coated balloon angioplasty to treat bare metal in-stent restenosis accompanied by late stent thrombosis but successful treatment of binary in-stent restenosis

Noninvasive detection of coronary artery stents by transthoracic echocardiography postprocessing subtraction technique

AIM

To explore the feasibility and value of transthoracic echocardiography (TTE) postprocessing subtraction technique in the detection of a stent in the coronary artery.

METHOD

Transthoracic echocardiography was used to examine 46 coronary artery stents in 30 patients by two-dimensional ultrasound postprocessing subtraction technique. The shape of each stent and its flow patency were observed. The patency was assessed according to blood flow and mosaic flow in the stent. Then, the results were compared with those of percutaneous coronary intervention (PCI) records and coronary angiography (CAG).

RESULTS

Transthoracic echocardiography detected 36 stents among 46 stents (two in the LMCA, 23 in the LAD, seven in the RCA, and two in the LCX); the detection rate was 78.3%. The average length of the stents was 21.8 ± 4.1 mm, and the average diameter was 2.4 ± 0.5 mm; both are shorter than those from PCI records (P < .001). Of the 36 stents, blood flow could be observed in 27. Compared with the results of CAG, TTE had 75% feasibility and 92.6% accuracy in detecting flow patency in the stents.

CONCLUSION

Transthoracic echocardiography postprocessing subtraction technique could be a noninvasive method for detecting a coronary artery stent and, although the measurements of stent length and diameter were shorter than those of PCI records, an accurate detection of flow patency in the stents was achieved.