Does Co-registration of OCT and Angiography Reduce Geographic Miss of Stent Implantation?

Background: When a stent fails to fully cover the lesion, it is termed "geographic miss"
(GM). Optical coherence tomography (OCT) is an intracoronary imaging modality that has
higher resolution than conventional intracoronary ultrasound. Although OCT allows
identification of the location of the culprit lesion and side branch using automated
measures, it is sometimes difficult to identify the exact segment corresponding to
angiography. Recently, co-registration of OCT and angiography has become available; however,
whether this reduces the incidence of GM during stenting is unknown.

Hypothesis: OCT reduces GM during percutaneous coronary intervention.

Objectives:

1. Determine the incidence of GM defined as residual disease* and significant edge
dissection† at proximal and distal reference

2. Determine the incidence of stent dislocation (distance between planned and actual
stented place)

3. Determine procedural findings (additional stent, total fluoro time, total contrast
volume)

- Minimum lumen area <4.0 mm2 in the presence of significant residual plaque within
5 mm distal and proximal to the stent edge.

- A flap of vessel wall of >60° is seen in ≥2 consecutive cross-section image
within 5 mm distal and proximal from stent edge Study Design and Methods:
Single-center, prospective, randomized study. Consented subjects who are to
undergo percutaneous coronary intervention are divided into 2 groups randomly
(OCT with co-registration vs OCT without co-registration). After stent
deployment guided by OCT, dissection, residual disease at the stent edge, and
distance between planned and actual stent location are assessed using OCT or
angiography. Additional stent deployment, procedure time, total fluoroscopy
time, and total contrast volume are also evaluated.

Sample size considerations: OCT with co-registration: 100, OCT without co-registration: 100
(α＝0.05, β ＝0.2). In a retrospective evaluation, the incidence of residual disease (lumen
area <4.0 mm2 in the presence of significant residual plaque) or significant stent edge
dissection was 36% (18/50, 34% [17/50] with residual stenosis, 4% [2/50] with significant
edge dissection). Under the assumption that GM occurs in 36% of patients without
co-registration and 18% of patients with co-registration, a group of 190 patients yields a
power 80% (with a 2-sided α=0.05) to detect a difference in GM between patients with and
without co-registration. In order to account for patient drop out and non-evaluable OCT
recordings (5%), a total of 200 patients will be enrolled.

Inclusion Criteria:

• Patients ≥18 years old who undergo percutaneous coronary intervention per clinical
indications.

Exclusion Criteria:

- Left main disease

- Ostial lesion at Right Coronary Artery

- Tortuous artery in which OCT is unable to pass

- Lesion at bypass graft

- In-stent restenosis

- Chronic total occlusion

- Cardiogenic shock (sustained [>10 min] systolic blood pressure <90 mm Hg in absence
of inotropic support or the presence of an intra-aortic balloon pump)

- Acute phase heart failure

- Sustained ventricular arrhythmias

- Known ejection fraction <35%

- Known severe valvular heart disease Known severe renal insufficiency (estimated
glomerular filtration rate <30 mL/min/1.72 m2)