Optical Coherence Tomography Guided Percutaneous Coronary Intervention With Nobori Stent Implantation in Patients With Non-ST-Segment-Elevation Myocardial Infarction (OCTACS) Trial: Difference in Strut Coverage and Dynamic Malapposition Patterns at 6 Months

BACKGROUND

Incomplete strut coverage has been documented an important histopathologic morphometric predictor for later thrombotic events. This study sought to investigate whether optical coherence tomography (OCT)-guided percutaneous coronary intervention with Nobori biolimus-eluting stent implantation in patients with non-ST-segment-elevation myocardial infarction would provide improved strut coverage at 6 months in comparison with angiographic guidance only.

METHODS AND RESULTS

One hundred patients were randomized 1:1 to either OCT-guided or angio-guided Nobori biolimus-eluting stent implantation. Postprocedure OCT was performed in all patients. In the OCT-guided group, prespecified criteria indicating additional intervention were related to (1) stent underexpansion, (2) strut malapposition, (3) edge dissection(s), and (4) residual stenosis at the distal or proximal reference segment(s). A final OCT was performed in case of reintervention. Six-month OCT follow-up was available in 85 patients. Twenty-three (46%) OCT-guided patients had additional postdilation or stenting. The percentage of acutely malapposed struts was substantially lower in the OCT-guided group (3.4% [interquartile range, 0.3-7.6] versus 7.8% [interquartile range, 2.3-19.4]; P<0.01). At 6-month follow-up, the OCT-guided group had a significantly lower proportion of uncovered struts; 4.3% [interquartile range, 1.2-9.8] versus 9.0% [interquartile range, 5.5-14.5], P<0.01. Furthermore, OCT-guided patients had significantly more completely covered stents: 17.5% versus 2.2%, P=0.02. The percentages of malapposed struts and struts being both uncovered and malapposed at follow-up were comparable between groups.

CONCLUSIONS

OCT-guided optimization of Nobori biolimus-eluting stent implantation improves strut coverage at 6-month follow-up in comparison with angiographic guidance alone.

CLINICAL TRIAL REGISTRATION

URL: http://www.clinicaltrials.gov. Unique identifier: NCT02272283.

Percutaneous Coronary Intervention Planning and Optimization with Optical Coherence Tomography

Coronary angiography confirms or excludes coronary artery disease, assesses lesions severity, and helps to decide percutaneous coronary interventions (PCI). Coronary angiography has clear limitations. Intravascular imaging guides PCI. Frequency domain optical coherence tomography (OCT) gained attention for accurate planning and guidance of complex PCI. High-speed OCT image acquisition enables prompt vessel assessment in stable and unstable patients. The high-resolution images provide precise tissue characterization and a reliable quantitative assessment of the coronary pathology. Immediately after stent implantation, OCT allows accurate evaluation of stent expansion and symmetry. Real-time angio-OCT co-registration integrates OCT into the PCI workflow for accurate decision making.

Does optical coherence tomography optimize results of stenting? Rationale and study design

BACKGROUND

To date, no randomized study has investigated the value of optical coherence tomography (OCT) in optimizing the results of coronary angioplasty for non-ST-segment elevation acute coronary syndromes.

METHODS

DOCTORS is a randomized, prospective, multicenter, open-label clinical trial to evaluate the utility of OCT to optimize results of angioplasty of a lesion responsible for non-ST-elevation acute coronary syndromes. Patients (n = 250) will be randomized to undergo OCT-guided angioplasty (use of OCT to optimize procedural result, including change to strategy with the possibility of additional interventions) or angioplasty under fluoroscopy alone. The primary end point is the functional result of the angioplasty procedure as assessed by fractional flow reserve (FFR) measured at the end of the procedure. Secondary end points include safety of OCT in the context of angioplasty for ACS, percentage of patients in whom OCT reveals suboptimal result of stenting, percentage of patients in whom a change in procedural strategy is decided based on OCT data, correlation between quantitative measures by OCT and FFR, determination of a threshold for quantitative OCT measure that best predicts FFR ≥ 0.90, and identification of OCT variables that predict postprocedure FFR. Adverse cardiac events (death, recurrent myocardial infarction, stent thrombosis, and repeat target lesion revascularization) at 6 months will be recorded.

CONCLUSION

The DOCTORS randomized trial (ClinicalTrials.gov NCT01743274) is designed to investigate whether use of OCT yields useful additional information beyond that obtained by angiography alone and, if so, whether this information changes physician strategy and impacts on the functional result of angioplasty as assessed by FFR.

Exploring coronary atherosclerosis with intravascular imaging

Coronary angiography has been widely used for five decades to evaluate a range of vascular pathologies and triage patients to therapeutic interventions. The inability to directly visualize the artery wall with conventional angiographic techniques has stimulated development of a number of intravascular imaging modalities. These approaches have the potential to provide a more comprehensive characterization of the burden, composition and functionality of atherosclerotic plaque, neointimal hyperplasia and allograft vasculopathy that develop within coronary arteries. The ability to use these modalities in vivo and in a serial fashion has provided a greater insight into the factors that underlie the disease process and guide therapeutic interventions.