Clinical significance of optical coherence tomography-guided angioplasty on treatment selection

Abstract

The present study aimed to observe whether optical coherence tomography (OCT)-guided angioplasty is able to provide useful clinical information beyond that obtained by angiography as well as provide recommendations for physicians that may improve treatment selection. This prospective study included 83 patients with coronary artery disease (>18 years) undergoing coronary angiography (CAG) for ST-elevation myocardial infarction (n=13), non-ST-elevation myocardial infarction (n=19), stable angina (n=22), unstable angina (n=10), silent ischemia (n=11), or elective percutaneous coronary intervention (n=8). Following the initial CAG (CAG-pre), the patients underwent OCT before angioplasty (OCT-pre, 24 patients), after angioplasty (OCT-post, 22 patients), or both (37 patients). The thrombus burden, calcification and plaque dissection or rupture were compared between the OCT-pre and CAG-pre recordings. Following angioplasty, stent malapposition, suboptimal stent deployment, suboptimal stent lesion coverage, and edge dissection were compared between OCT-post and CAG-post alone. Among the 83 patients, 45.7% had single-vessel and 54.3% had multiple-vessel disease. OCT pre- and post-angioplasty revealed significantly more information on the procedure than CAG alone. This clinical information changed the clinical strategies in 41/83 (49.4%) patients, including 58 modifications of therapeutic strategy (69.9%, 58/83): Thrombus aspiration in 2 cases (2.4%), administration of glycoprotein IIb/IIIa inhibitors in 8 cases (9.6%), additional balloon inflation in 23 cases (27.7%), additional stent implantation in 17 cases (20.5%), avoiding stent implantation in 4 cases (4.8%), collateral intervention in 2 cases (2.4%), and guidewire reposition in 2 cases (2.4%). In conclusion, OCT-pre and OCT-post provided additional clinical information beyond that obtained by angiography alone, which resulted in modification of the treatment strategies in half of the included patients.

Keywords: coronary angiography; coronary artery disease; optical coherence tomography; percutaneous coronary intervention.

Figure 1.

Flow chart of OCT-guided angioplasty and treatment strategy alterations based on the OCT data. OCT, optical coherence tomography; OCT-pre, OCT performed following the initial coronary angiography; OCT-post, OCT performed following angioplasty.

Figure 2.

Comparisons of CAG and OCT findings in a patient with variant angina. (A) CAG image showing vascular stenosis (arrow) in the middle segment of the left anterior descending artery. (B) OCT image showing vascular stenosis with a thrombus along the vessel wall in situ without significant atherosclerotic lesions. The patient's symptoms were relieved by the administration of nitroglycerin. Therefore, coronary thrombosis with occasional coronary spasms was considered in this patient following the OCT examination. Accordingly, stent implantation was not conducted and the clinical treatment strategy was changed to the administration of glycoprotein IIb/IIIa receptor inhibitor and antispasmodic medications. Follow-up demonstrated treatment efficacy. CAG, coronary angiography; OCT, optical coherence tomography

Figure 3.

Comparison of OCT and CAG findings in patients after the implantation of a single stent in the proximal LAD. (A and B) CAG images demonstrating no residual stenosis in the ostium of the LAD post-stent implantation (marked as *) and 40% stenosis in the distal edge of the stent (marked as **). (C) OCT image showing the ostium of LAD (marked as *) in which incomplete expansion with malapposition was found by OCT. (D) OCT image showing the distal edge of the stent (marked as *) and edge dissection with stenosis. The treatment strategy was adjusted to the implantation of another stent at the distal edge of the original stent, while the proximal portion of the original stent in the ostium of LAD was deflated by a high-pressure balloon. CAG, coronary angiography; OCT, optical coherence tomography; LAD, left anterior descending artery.

Figure 4.

OCT image obtained at 6 months of follow-up in a patient with stent malapposition in the left anterior descending artery. Coronary angiography revealed stenosis distal to the stent; however, OCT identified stent malapposition, endothelial uncovering on the struts of the stent, and that the guidewire (arrow) was protruding beyond the stent. The treatment strategy consisted of guidewire repositioning. OCT, optical coherence tomography.