OCT or Angiography Guidance for PCI in Complex Bifurcation Lesions.

BACKGROUND: Imaging-guided percutaneous coronary intervention (PCI) is associated with better clinical outcomes than angiography-guided PCI. Whether routine optical coherence tomography (OCT) guidance in PCI of lesions involving coronary-artery branch points (bifurcations) improves clinical outcomes as compared with angiographic guidance is uncertain. METHODS: We conducted a multicenter, randomized, open-label trial at 38 centers in Europe. Patients with a clinical indication for PCI and a complex bifurcation lesion identified by means of coronary angiography were randomly assigned in a 1:1 ratio to OCT-guided PCI or angiography-guided PCI. The primary end point was a composite of major adverse cardiac events (MACE), defined as death from a cardiac cause, target-lesion myocardial infarction, or ischemia-driven target-lesion revascularization at a median follow-up of 2 years. RESULTS: We assigned 1201 patients to OCT-guided PCI (600 patients) or angiography-guided PCI (601 patients). A total of 111 patients (18.5%) in the OCT-guided PCI group and 116 (19.3%) in the angiography-guided PCI group had a bifurcation lesion involving the left main coronary artery. At 2 years, a primary end-point event had occurred in 59 patients (10.1%) in the OCT-guided PCI group and in 83 patients (14.1%) in the angiography-guided PCI group (hazard ratio, 0.70; 95% confidence interval, 0.50 to 0.98; P = 0.035). Procedure-related complications occurred in 41 patients (6.8%) in the OCT-guided PCI group and 34 patients (5.7%) in the angiography-guided PCI group. CONCLUSIONS: Among patients with complex coronary-artery bifurcation lesions, OCT-guided PCI was associated with a lower incidence of MACE at 2 years than angiography-guided PCI. (Funded by Abbott Vascular and others; OCTOBER ClinicalTrials.gov number, NCT03171311.).

Long-term multimodality imaging follow-up of ST-segment elevation myocardial infarction patients treated with bioresorbable vascular scaffold: advantages and challenges.

BACKGROUND: Multislice computed tomography (MSCT) offers a non-invasive method of imaging bioresorbable scaffolds (BRS). OBJECTIVES: To investigate the advantages and challenges using MSCT in the follow-up after BRS implantation. METHOD: The BRS cohort consisting of 31 patients in the 'BRS in STEMI' trial was examined by multimodality imaging and followed long-term. Minimum lumen area (MLA) and average lumen area (ALA) were examined 12 and 36 months after BRS implantation with MSCT. Optical coherence tomography (OCT) at 12 months was used as a reference. RESULTS: Measured by MSCT, the mean MLA was 0.05 ±â€…1.32 mm² ( P  = 0.85), but ALA was 1.32 (±2.59 mm², P  = 0.015) greater than by OCT. ALA and MLA did not change significantly from 12 to 36 months. MSCT identified all cases of restenosis but missed one patient with massive malapposition. CONCLUSION: Our data support using MSCT in the follow-up after BRS implantation. Invasive investigation should still be considered for patients with unexplained symptoms.

Validation of a semi-automatic software for optical coherence tomography - analysis in heart transplanted patients.

Optical Coherence Tomography (OCT) is an intravascular imaging modality enabling detailed evaluation of cardiac allograft vasculopathy (CAV) after heart transplantation (HTx). However, its clinical application remains hampered by time-consuming manual quantitative analysis. We aimed to validate a semi-automated quantitative OCT analysis software (Iowa Coronary Wall Analyzer, ICWA-OCT) to improve OCT-analysis in HTx patients. 23 patients underwent OCT evaluation of all three major coronary arteries at 3 months (3M) and 12 months (12M) after HTx. We analyzed OCT recordings using the semiautomatic software and compared results with measurements from a validated manual software. For semi-automated analysis, 31,228 frames from 114 vessels were available. The validation was based on a subset of 4287 matched frames. We applied mixed model statistics to accommodate the multilevel data structure with method as a fixed effect. Lumen (minimum, mean, maximum) and media (mean, maximum) metrics showed no significant differences. Mean and maximum intima area were underestimated by the semi-automated method (ß-methodmean = - 0.289 mm2, p < 0.01; ß-methodmax = - 0.695 mm2, p < 0.01). Bland-Altman analyses showed increasing semi-automatic underestimation of intima measurements with increasing intimal extent. Comparing 3M to 12M progression between methods, mean intimal area showed minor underestimation (ß-methodmean = - 1.03 mm2, p = 0.04). Lumen and media metrics showed excellent agreement between the manual and semi-automated method. Intima metrics and progressions from 3M to 12M were slightly underestimated by the semi-automated OCT software with unknown clinical relevance. The semi-automated software has the future potential to provide robust and time-saving evaluation of CAV progression.

Everolimus-eluting bioresorbable scaffold versus everolimus-eluting metallic stent in primary percutaneous coronary intervention of ST-segment elevation myocardial infarction: a randomized controlled trial.

BACKGROUND: Primary percutaneous coronary intervention with implantation of a metallic drug-eluting stent (DES) is the standard treatment for patients presenting with ST-elevation myocardial infarction (STEMI). Implantation of a bioresorbable scaffold (BRS) during STEMI represents a novel strategy without intravascular metal. OBJECTIVE: The aim of the study was to investigate 12-month healing response in an STEMI population after implantation of either the Absorb BRS or Xience DES (Abbott Vascular, USA). METHODS: The present trial was a prospective, randomized, controlled, nonblinded, noninferiority study with planned inclusion of 120 patients with STEMI. Patients were randomly assigned 1:1 to treatment with Absorb BRS or Xience DES. Implantation result and healing response were evaluated by angiography and optical coherence tomography (OCT) at baseline and 12-month follow-up. The primary endpoint was minimum flow area (MFA) assessed at 12 months. Coronary stent healing index (CSHI) was calculated from OCT images. RESULTS: Out of 66 included patients, 58 had follow-up OCT after 12 months, and 49 entered matched analysis. One death occurred in each group; none were stent-related. MFA was 5.13 ± 1.70 mm2 (95% CI, 4.44-5.82) in the BRS group compared with 6.30 ± 2.49 mm2 (95% CI, 5.22-7.37) (P = 0.06) in the DES group. Noninferiority could not be evaluated. CSHI for both groups had a median score of 3. CONCLUSION: The DES group performed numerically better in primary and secondary endpoints, but the CSHI showed good stent healing in both groups.

Bioresorbable magnesium scaffold in the treatment of simple coronary bifurcation lesions: The BIFSORB pilot II study.

OBJECTIVES: To evaluate the feasibility, safety, and healing response of a magnesium-based bioresorbable scaffold (BRS) in the treatment of simple bifurcation lesions using the single stent provisional technique. BACKGROUND: BRS may hold potential advantages in the treatment of coronary bifurcation lesions, however low radial strength and expansion capacity has been an issue with polymer-based scaffolds. The magnesium BRS may prove suitable for bifurcation treatment as its mechanical properties are closer to those of permanent metallic drug-eluting stents. METHODS: The study was a proof-of-concept study with planned inclusion of 20 patients with stable angina pectoris and a bifurcation lesion involving a large side branch (SB) > 2.5 mm with less than 50% diameter stenosis. Procedure and healing response were evaluated by optical coherence tomography (OCT). The main endpoints were a composite clinical safety endpoint and an OCT healing index at 1 month (range: 0-98). RESULTS: Eleven patients were included in the study. The study was prematurely terminated due to scaffold fractures and embolization of scaffold fragments in three cases requiring bailout stenting with drug-eluting stents. One patient underwent bypass surgery at 3 months due to stenosis proximal to the study segment. All SB were patent for 1 month. One-month OCT evaluation showed strut coverage of 96.9% and no malapposition. Scaffold fractures and uncovered jailing struts resulted in a less favorable mean OCT healing index score of 10.4 ± 9.0. CONCLUSIONS: Implanting a magnesium scaffold by the provisional technique in nontrue bifurcation lesions was associated with scaffold fracture, embolization of scaffold fragments, and a high need for bailout stenting.

A randomized clinical study using optical coherence tomography to evaluate the short-term effects of high-intensity interval training on cardiac allograft vasculopathy: a HITTS substudy.

Cardiac allograft vasculopathy (CAV) remains a leading cause of long-term mortality after heart transplantation. Both preventive measures and treatment options are limited. This study aimed to evaluate the short-term effects of high-intensity interval training (HIT) on CAV in de novo heart transplant (HTx) recipients as assessed by optical coherence tomography (OCT). The study population was a subgroup of the 81-patient HITTS study in which HTx recipients were randomized to HIT or moderate intensity continuous training (MICT) for nine consecutive months. OCT images from baseline and 12 months were compared to assess CAV progression. The primary endpoint was defined as the change in the mean intima area. Paired OCT data were available for 56 patients (n = 23 in the HIT group and n = 33 in the MICT group). The intima area in the entire study population increased by 25% [from 1.8±1.4 mm2 to 2.3±2.0 mm2 , P < .05]. The change was twofold higher in the MICT group (.6±1.2 mm2 ) than in the HIT group (.3±.6 mm2 ). However, the treatment effect of HIT was not significant (treatment effect = -.3 mm2 , 95% CI [-.825 to .2 mm2 ] P = .29). These results suggest that early initiation of HIT compared with MICT does not attenuate CAV progression in de novo HTx recipients.

Mechanical performance and healing patterns of the novel sirolimus-eluting bioresorbable Fantom scaffold: 6-month and 9-month follow-up by optical coherence tomography in the FANTOM II study.

Objectives: We aimed to evaluate the mechanical properties and healing patterns 6 and 9 months after implantation of the sirolimus-eluting Fantom bioresorbable scaffold (BRS). Background: The Fantom BRS (Reva Medical, San Diego, USA) has differentiating properties including radiopacity, strut thickness of 125 µm, high expansion capacity and has demonstrated favourable mid-term clinical and angiographic outcomes. Methods and results: FANTOM II was a prospective, single arm study with implantation of the Fantom BRS in 240 patients with stable angina pectoris. Guidance by optical coherence tomography (OCT) was encouraged and was repeated at 6-month (cohort A) or 9-month follow-up (cohort B). Matched baseline and follow-up OCT recordings were available in 152 patients. In-scaffold mean lumen area in cohort A was 6.8±1.7 mm2 and 5.7±1.4 mm2 at baseline and follow-up (p<0.0001) and was 7.2±1.6 mm2 and 5.6±1.4 mm2 in cohort B (p<0.0001). Mean scaffold area remained stable from 7.1±1.5 mm2 at baseline to 7.2±1.4 mm2 at 6 months (p=0.12), and from 7.4±1.5 mm2 to 7.3±1.4 mm2 at 9 months. Strut malapposition was median 0.8 (IQR 0.0;3.5)% and 1.8 (IQR 0.3;6.0)% at baseline and was 0.0 (IQR 0.0;0.0)% in both groups at 6-month and 9-month follow-up. Strut tissue coverage was 98.1 (IQR 95.9;99.4)% at 6 months and 98.9 (IQR 98.3;100.0)% at 9 months. Conclusions: The novel Fantom BRS had favourable healing patterns at 6-month and 9-month follow-up as malapposition was effectively resolved and strut coverage was almost complete. The scaffold remained stable through follow-up with no signs of systematic late recoil.

Mechanical performance and healing patterns of the novel sirolimus-eluting bioresorbable Fantom scaffold: 6-month and 9-month follow-up by optical coherence tomography in the FANTOM II study

OBJECTIVES: We aimed to evaluate the mechanical properties and healing patterns 6 and 9 months after implantation of the sirolimus-eluting Phantom bioresorbable scaffold (BRS). BACKGROUND: The Phantom BRS (Reva Medical, San Diego, USA) has differentiating properties including radiopacity, strut thickness of 125 µm, high expansion capacity and has demonstrated favorable mid-term clinical and angiographic outcomes. METHODS AND RESULTS: FANTOM II was a prospective, single arm study with implantation of the Phantom BRS in 240 patients with stable angina pectoris. Guidance by optical coherence tomography (OCT) was encouraged and was repeated at 6-month (cohort A) or 9-month follow-up (cohort B). Matched baseline and follow-up OCT recordings were available in 152 patients. In-scaffold mean lumen area in cohort A was 6.8±1.7 mm2 and 5.7±1.4 mm2 at baseline and follow-up (p<0.0001) and was 7.2±1.6 mm2 and 5.6±1.4 mm2 in cohort B (p<0.0001). Mean scaffold area remained stable from 7.1±1.5 mm2 at baseline to 7.2±1.4 mm2 at 6 months (p=0.12), and from 7.4±1.5 mm2 to 7.3±1.4 mm2 at 9 months. Strut malposition was median 0.8 (IQR 0.0;3.5)% and 1.8 (IQR 0.3;6.0)% at baseline and was 0.0 (IQR 0.0;0.0)% in both groups at 6-month and 9-month follow-up. Strut tissue coverage was 98.1 (IQR 95.9;99.4)% at 6 months and 98.9 (IQR 98.3;100.0)% at 9 months. CONCLUSIONS: The novel Phantom BRS had favorable healing patterns at 6-month and 9-month follow-up as malposition was effectively resolved and strut coverage was almost complete. The scaffold remained stable through follow-up with no signs of systematic late recoil. (AU)

Diagnostic Performance of In-Procedure Angiography-Derived Quantitative Flow Reserve Compared to Pressure-Derived Fractional Flow Reserve: The FAVOR II Europe-Japan Study.

BACKGROUND: Quantitative flow ratio (QFR) is a novel modality for physiological lesion assessment based on 3-dimensional vessel reconstructions and contrast flow velocity estimates. We evaluated the value of online QFR during routine invasive coronary angiography for procedural feasibility, diagnostic performance, and agreement with pressure-wire-derived fractional flow reserve (FFR) as a gold standard in an international multicenter study. METHODS AND RESULTS: FAVOR II E-J (Functional Assessment by Various Flow Reconstructions II Europe-Japan) was a prospective, observational, investigator-initiated study. Patients with stable angina pectoris were enrolled in 11 international centers. FFR and online QFR computation were performed in all eligible lesions. An independent core lab performed 2-dimensional quantitative coronary angiography (2D-QCA) analysis of all lesions assessed with QFR and FFR. The primary comparison was sensitivity and specificity of QFR compared with 2D-QCA using FFR as a reference standard. A total of 329 patients were enrolled. Paired assessment of FFR, QFR, and 2D-QCA was available for 317 lesions. Mean FFR, QFR, and percent diameter stenosis were 0.83±0.09, 0.82±10, and 45±10%, respectively. FFR was ≤0.80 in 104 (33%) lesions. Sensitivity and specificity by QFR was significantly higher than by 2D-QCA (sensitivity, 86.5% (78.4-92.4) versus 44.2% (34.5-54.3); P<0.001; specificity, 86.9% (81.6-91.1) versus 76.5% (70.3-82.0); P=0.002). Area under the receiver curve was significantly higher for QFR compared with 2D-QCA (area under the receiver curve, 0.92 [0.89-0.96] versus 0.64 [0.57-0.70]; P<0.001). Median time to QFR was significantly lower than median time to FFR (time to QFR, 5.0 minutes [interquartile range, -6.1] versus time to FFR, 7.0 minutes [interquartile range, 5.0-10.0]; P<0.001). CONCLUSIONS: Online computation of QFR in the catheterization laboratory is clinically feasible and is superior to angiographic assessment for evaluation of intermediary coronary artery stenosis using FFR as a reference standard. CLINICAL TRIAL REGISTRATION: URL: https://www.clinicaltrials.gov. Unique identifier: NCT02959814.

Detection of early changes in the coronary artery microstructure after heart transplantation: A prospective optical coherence tomography study.

BACKGROUND: Optical coherence tomography (OCT) enables in-vivo cardiac allograft vasculopathy (CAV) microstructure characterization. Early coronary artery microstructure changes after heart transplantation (HTx) may provide valuable mechanistic information regarding CAV development. Our in this study was to describe and characterize changes in the coronary artery microstructure during the first year after HTx using serial OCT scans. METHODS: Twenty-six patients were enrolled at routine baseline coronary angiography 3 months after HTx. Coronary OCT scans were performed on all 3 major vessels at baseline and were repeated 12 months after HTx. We contoured the vessel layers for absolute and relative measurements. Lipid plaques, calcified plaques, layered fibrotic plaques (LFPs) and bright spots were analyzed by delineating circumferential borders and measuring angulation of total circumference. RESULTS: A total of 8,789 frames from 71 vessels were analyzed after 3 and 12 months (vessel length 79 ± 24 mm vs 82 ± 23 mm, respectively, p = 0.39). Mean intima area increased by 20% from 3 months to 12 months (1.6 [1.2 to 2.7] mm2 vs 1.9 [1.3 to 3.2] mm2, p < 0.0001). Mean lumen area decreased by 2% (9.1 [7.5 to 11.6] mm2 vs 8.9 [6.9 to 10.9] mm2, p < 0.01). LFPs showed an almost 5-fold increase at follow-up (1.0% [0% to 6.5%] vs 4.8% [0% to 24.5%], p < 0.0001). Bright spots were also detected more frequently at 12 months (0% [0% to 2.8%] vs 0.8% [0% to 6.8%], p < 0.001). We found no significant difference in extent of lipid plaque (p = 0.78) or calcified plaque (p = 0.37) during follow-up. The intima area change and LFP progression during follow-up correlated strongly (r2 = 0.51, p < 0.0001). CONCLUSIONS: Early CAV formation during the first year after HTx is characterized by a pronounced intima layer thickening strongly associated with LFP progression. In contrast, the extent of lipid plaque and calcifications remained stable. LFP formation may be a key mechanism in CAV.