Intravascular Ultrasound Research Articles

Comparison of deep learning-based image segmentation methods for intravascular ultrasound on retrospective and large image cohort study

ObjectivesThe aim of this study was to investigate the generalization performance of deep learning segmentation models on a large cohort intravascular ultrasound (IVUS) image dataset over the lumen and external elastic membrane (EEM), and to assess the consistency and accuracy of automated IVUS quantitative measurement parameters.MethodsA total of 11,070 IVUS images from 113 patients and pullbacks were collected and annotated by cardiologists to train and test deep learning segmentation models. A comparison of five state of the art medical image segmentation models was performed by evaluating the segmentation of the lumen and EEM. Dice similarity coefficient (DSC), intersection over union (IoU) and Hausdorff distance (HD) were calculated for the overall and for subsets of different IVUS image categories. Further, the agreement between the IVUS quantitative measurement parameters calculated by automatic segmentation and those calculated by manual segmentation was evaluated. Finally, the segmentation performance of our model was also compared with previous studies.ResultsCENet achieved the best performance in DSC (0.958 for lumen, 0.921 for EEM) and IoU (0.975 for lumen, 0.951 for EEM) among all models, while Res-UNet was the best performer in HD (0.219 for lumen, 0.178 for EEM). The mean intraclass correlation coefficient (ICC) and Bland–Altman plot demonstrated the extremely strong agreement (0.855, 95% CI 0.822–0.887) between model's automatic prediction and manual measurements.ConclusionsDeep learning models based on large cohort image datasets were capable of achieving state of the art (SOTA) results in lumen and EEM segmentation. It can be used for IVUS clinical evaluation and achieve excellent agreement with clinicians on quantitative parameter measurements.

Stabilization of Rapidly Progressive Cardiac Allograft Vasculopathy Using mTOR Inhibition After Heart Transplantation

Inhibition of the mammalian target of rapamycin (mTor) pathway after heart transplantation has been associated with reduced progression of coronary allograft vasculopathy (CAV). The application of low-dose mTOR inhibition in the setting of modern immunosuppression, including tacrolimus, remains an area of limited exploration. This retrospective study included patients who received heart transplantation between January 2009 and January 2019 and had baseline, 1-year and 2-3-year coronary angiography with intravascular ultrasound (IVUS). Intimal thickness in 5 segments along the left anterior descending artery was compared across imaging time points in patients who were transitioned to low-dose mTOR inhibitor (sirolimus) vs standard treatment with mycophenolate on a background of tacrolimus. Long-term adverse cardiovascular outcomes (revascularization, severe CAV, retransplant, and cardiovascular death) were also assessed. Among 216 patients (mean age 51.5 ± 11.9 years, 77.8% men, 80.1% white), 81 individuals (37.5%) were switched to mTOR inhibition. mTOR inhibition was associated with a reduction in intimal thickness by 0.05 mm (95% CI 0.02-0.07; P < 0.001). This reduction was driven by patients who met the criteria for rapidly progressive CAV 1-year post-transplant (0.12 mm; P = 0.016 for interaction). After a median follow-up of 8.6 (IQR 6.6-11) years, 40 patients had major adverse cardiovascular outcomes. The use of mTOR inhibitors was not significantly associated with cardiovascular outcomes (P = 0.669). Transitioning patients after heart transplantation to an immunosuppression regimen composed of low-dose mTOR inhibition and tacrolimus was associated with a lack of progression of CAV, particularly in those with rapidly progressive CAV at 1 year, but not with long-term cardiovascular outcomes.

Intravascular imaging guided versus coronary angiography guided percutaneous coronary intervention: systematic review and meta-analysis

ObjectiveTo assess the absolute treatment effects of intravascular imaging guided versus angiography guided percutaneous coronary intervention in patients with coronary artery disease, considering their baseline risk.DesignSystematic review and meta-analysis.Data sourcesPubMed/Medline,...

Clinical outcomes of deferred lesions by IVUS versus FFR-guided treatment decision: the FLAVOUR trial substudy

Abstract Background There is limited data regarding the safety of deferral of percutaneous coronary intervention (PCI) based on intravascular ultrasound (IVUS) findings. Current study sought to compare the prognosis between deferred lesions based on IVUS and FFR (fractional flow reserve)-guided treatment decision. Methods Study population was derived from FLAVOUR trial which is a multinational, open-label, randomized, and non-inferiority trial that compared 2-year clinical outcomes between IVUS and FFR-guided treatment decision using predefined criteria. In both IVUS and FFR groups, vessels were classified into deferred or revascularized vessels, and patients into those with or without deferred lesion. Vessel-oriented composite outcomes (VOCO) (cardiac death, target-vessel myocardial infarction, or target-vessel revascularization) in deferred vessels and patient-oriented composite outcomes (POCO) (death, myocardial infarction, or any revascularization) in patients with deferred lesion were compared between IVUS and FFR group. Results A total of 1682 patients and 1820 vessels were analyzed. At 2 years, there is no difference in cumulative incidence of VOCO in deferred vessels between IVUS and FFR groups (3.8% vs. 4.1%; hazard ratio [HR] 0.91; 95% confidence interval [CI] 0.47-1.75; P=0.771). The risk of VOCO was comparable between deferred and revascularized vessels following both IVUS (3.8% vs. 3.5%; HR 1.09; 95% CI 0.54-2.19; P=0.813) and FFR-guided treatment decision (4.1% vs. 3.6%; HR 1.14; 95% CI 0.56-2.32; P=0.715). In comparison of POCO in patients with deferred lesion, there was no significant difference between IVUS and FFR groups (6.2% vs. 5.9%; HR 1.05; 95% CI 0.61-1.80; P=0.856). Conclusion In patients with intermediate coronary artery stenosis, deferral of PCI based on IVUS-guided treatment decision showed comparable risk of clinical events with FFR-guided treatment decision.

Evaluation of the residual myocardial ischemia after PCI to long diffuse left anterior descending artery lesions: comparison of IVUS vs FFR

Abstract Background Up to 30% of coronary artery lesions continue to induce myocardial ischemia (FFR ≤ 0.8) despite angiographically successful PCI. This proportion is even larger after PCI to the left anterior descending (LAD) artery as it supplies blood to the largest myocardial territory and often has diffuse disease. Post PCI FFR is an important tool to risk stratify patients, as lower values are associated with a worse prognosis. Therefore, achieving a good functional PCI result after LAD treatment is crucial. PCI optimization tools such as intravascular ultrasound (IVUS) and FFR were both proven to be superior to angiography-guided PCI, however, there is a lack of studies comparing these two modalities head-to-head, especially in the long LAD lesions. Purpose To compare functional PCI result assessed with FFR measured immediately post PCI and at 9-12 months follow-up between IVUS optimization and FFR optimization strategies after percutaneous treatment of long LAD lesions. Methods This was a single center observational study, which enrolled 127 patients. 61 patients underwent PCI optimized with FFR (historical FFR optimization group) and for 66 patients PCI was optimized with IVUS. FFR measurement was performed using intravenous adenosine with a pullback before and after PCI for all patients. Post PCI FFR was recorded in both groups when the PCI result was considered to be final and no more optimization was performed afterwards. Patients also underwent invasive follow-up at 9-12 months post PCI with FFR measurement at the same location (Figure 1). A case example of IVUS optimization strategy is demonstrated in Figure 2. Results The average patients age (66.5 ± 9.5) and baseline clinical characteristics (males 70.1%, diabetes 20.5%, hypertension 92.1%, dyslipidemia 91.3%, smoking 23.0%, chronic kidney disease 21.3%) did not differ between IVUS and FFR optimization groups. IVUS strategy resulted in the longer stented segment compared to FFR group (62 [48-75] mm vs 52 [36-63] mm, p=0.03). The proportion of patients with optimal functional PCI result (FFR &amp;gt; 0.9) did not differ significantly between two groups (16.7% in IVUS group vs 15% in FFR group), however, there was a lower incidence of residual myocardial ischemia in the IVUS optimization group: 0% of patients with post-PCI FFR ≤ 0.8 in the IVUS group vs 13.3% in the FFR group (p=0.002). The trend for smaller ischemia prevalence in IVUS optimization strategy continued during follow-up: there were 4.5% of patients with target vessel related myocardial ischemia in IVUS group and 18.0% in FFR group (p=0.015). Conclusion(s) In the treatment of long LAD lesions IVUS PCI optimization strategy was associated with lower incidence of poor functional PCI result and smaller ischemia burden at follow-up compared to FFR optimization strategy. The implementation of intravascular imaging should be mandatory in the treatment of long diffuse coronary disease.Figure 1Figure 2

Discordance between quantitative coronary angiography and fractional flow reserve or intravascular ultrasound: a substudy of the FLAVOUR trial

Abstract Background Discrepancies between quantitative coronary angiography (QCA) and fractional flow reserve (FFR) or intravascular ultrasound (IVUS) are often observed in coronary lesions with intermediate stenosis. Objectives We investigated the impact of physiology- or intracoronary imaging-directed revascularization strategies on clinical outcomes in patients with discordant coronary lesions between QCA and FFR or IVUS. Methods This study was a post hoc analysis of the FLAVOUR study, an investigator-initiated, prospective, randomized, open-label, multinational trial performed at 18 sites in Korea and China. In the FLAVOUR study, 200 patients with ≥60% diameter stenosis (DS) deferred percutaneous coronary intervention (PCI) according to FFR &amp;gt; 0.8 (n=141) or a minimal lumen area &amp;gt; 3 mm2 or 3-4 mm2 with a plaque burden &amp;lt;70% on IVUS whereas 351 patients with &amp;lt;60% DS performed PCI according to positive FFR (n=118) or positive IVUS (n=233) results. The primary outcome was a patient-oriented composite outcome (POCO), a composite of death, myocardial infarction, or revascularization. Results The incidence of discordance was 28.1% in the FFR group and 32.4% in the IVUS group. At 24 months, among patients with ≥60% DS, the incidence of POCO was similar between FFR-guided and IVUS-guided deferral strategies (4.4% vs. 3.4%, p=0.757). Among patients with &amp;lt;60% DS, FFR-directed or IVUS-directed PCI did not differ in the POCO incidence (5.2% vs. 2.6%, p=0.207). However, FFR-guided PCI showed a higher incidence of periprocedural myocardial infarction than IVUS-guided PCI in &amp;lt;60% DS lesions (2.6% vs. 0.0%, p=0.014). Conclusions In patients with discordant intermediate stenosis between QCA and FFR or IVUS, physiology- and imaging-directed revascularization strategies are comparable concerning POCO at 24 months.

Routine functional testing in high-risk patients after imaging- or physiology-guided percutaneous coronary intervention

Abstract Background Imaging-guided or physiology-guided percutaneous coronary intervention (PCI) improved clinical outcomes in complex coronary artery disease. However, it is not known to what extent routine functional testing after imaging or physiology-guided PCI affect clinical outcomes among high-risk patients. Objectives To assess clinical impact of routine functional test or standard care alone after intravascular ultrasound (IVUS) or fractional flow reserve(FFR) guided PCI. Methods Of the 1706 randomized patients with high-risk anatomical or clinical features enrolled in the POST-PCI (Pragmatic Trial Comparing Symptom-Oriented versus Routine Stress Testing in High-Risk Patients Undergoing Percutaneous Coronary Intervention) trial, 1269 patients underwent IVUS-guided PCI and 609 patients underwent FFR-guided PCI. The primary outcome was a composite of death from any cause, myocardial infarction, or hospitalization for unstable angina at 2 years. Results The rate of the 2-year primary outcomes was similar between strategies of routine functional-testing or standard-care in IVUS use group (5.3% vs. 6.6%, respectively; HR, 0.79; 95% CI, 0.50–1.24; P=0.30) and in IVUS non-use group (5.7% vs. 3.8%, respectively; HR,1.52; 95% CI, 0.63–3.68; P=0.21); there was no significant interaction between IVUS use and follow up strategies (p for interaction=0.21). The rate of the 2-year outcomes was not significantly different with functional-testing or standard-care in FFR use group (2.6% vs. 3.9%, respectively; HR, 0.65; 95% CI, 0.26–1.58, P=0.34) and in FFR non-use group (7.0% vs. 7.1%, respectively; HR, 0.99; 95% CI, 0.63–1.55, P=0.97) without significant interaction (p for interaction=0.59). Conclusions In patients with high-risk PCI, IVUS and FFR use did not affect clinical outcome of routine surveillance stress testing and standard-care alone during follow-up.TableFigure

Impact of intravascular ultrasound parameters on revascularization decision in grey zone fractional flow reserve: data from IRIS FFR registry

Abstract Background The optimal revascularization strategy for coronary stenosis with grey-zone fractional flow reserve (FFR) value (0.75-0.80) is still debated. This study investigated the prognostic impact of the lesion characteristics measured by intravascular ultrasound (IVUS) in grey-zone FFR. Methods A total of 734 native coronary stenoses with grey-zone FFR in 734 patients from the prospective multicenter IRIS-FFR registry were simultaneously evaluated by IVUS. The primary outcome was a composite of cardiac death, myocardial infarction and target vessel revascularization. Results Among the 734 patients, revascularization was deferred for 293 patients and performed for 441. During a median follow-up of 4.4 years, the primary outcome occurred in 31 (10.6%) patients in deferred group and 42 (9.5%) in performed group. With the best cut-off values of 2.62 mm2 (area under curve 0.64) and 75% (area under curve 0.63), respectively, the minimal lumen area (MLA) and plaque burden (PB) at the MLA site were significant predictors of the primary outcome in the deferred group, whereas they were not predictive in the performed group. Revascularization performed group showed lower incidence rate of the primary outcome than deferral group in 348 patients with smaller MLA (&amp;lt;2.62 mm2) and larger PB (&amp;gt;75%) (19.3% vs. 36.8%, hazard ratio 0.58, 95% confidence interval [CI] 0.34-0.91, P=0.017), whereas other patients showed similar incidence rate of primary outcome between two groups (15.7% vs. 19.8%, hazard ratio 0.78, 95% CI 0.47-1.31, P=0.35). Conclusions For coronary stenoses with grey-zone FFR and smaller MLA and larger PB measured by IVUS, revascularization was associated with better clinical outcomes than deferral. The incorporation of FFR and IVUS may improve the revascularization decision in native coronary stenoses with grey-zone FFR.

Intracoronary imaging guided percutaneous coronary intervention of stent restenosis: does it make a difference?

Abstract Background In-stent restenosis (ISR) remains the most common cause of stent failure after percutaneous coronary intervention (PCI). Compared to coronary angiography (CA), intracoronary imaging (ICI) provides a more accurate and detailed characterization of the degree of ISR and may help identify the underlying pathophysiological mechanism. Although recommended in the European guidelines, the impact of ICI in clinical outcomes in ISR is still under discussion. Purpose Our study aimed to analyze and compare clinical outcomes between CA PCI (group 1 - G1) and ICI-guided PCI (Intravascular ultrasound (IVUS) or optical coherence tomography (OCT)) (group 2 - G2). Methods We performed a retrospective single-center review of all consecutive patients with ISR treated in our center from September 2014 to January 2022. Patients with acute stent thrombosis were excluded. Primary endpoint was defined as death by all causes and secondary endpoint as a composite of cardiovascular (CV) mortality, culprit ISR PCI and ischemic stroke. Results 130 patients were included (mean age 66.23 ± 11.832 years, 77.7% male and mean follow-up period (FUP) 48.70 ± 27.356 months). Mean left ventricular ejection fraction was 50.19 ± 10.509%, 66.2% had dyslipidemia, 45.3% hypertension, 38.5% diabetes, 36.2% heart failure and 29.2% previous multivessel PCI. A total of 142 ISR lesions from 136 arteries were treated and ICI was used in 37 (28.5%) patients (IVUS in 16 (12.3%) and OCT in 21 (16.2%)). The ISR coronary segment and pattern is described in Table 1. The mechanism for ISR was identified in 23 lesions. The most common indication for coronary angiography was stable angina in 34.6% and NSTEMI in 31.5% and ISR was the culprit in 128 (98.5%) of the cases. The groups were well matched regarding baseline characteristics and comorbidities. PCI strategy was more often drug-eluting stenting (DES) vs drug-coated balloon (DCB) in group 2 (DES 18.3% vs 51.4% and DCB 81.7% vs 43.2% in G1 and G2 respectively). And, as expected, treatment of bifurcation lesions was more frequent in group 2 (9.7% G1 vs 30.6% G2). During the FUP there were 10 (7.7%) CV deaths and 19 (14.6%) non-CV deaths (19 in G1 and 0 in G2). The composite outcome of CV mortality, ischemic stroke and culprit ISR PCI occurred in 19 (20.2%) patients in G1 and 1 (2.7%) patient in G2. The use of ICI was associated with reduced all-cause mortality (HR=0.667 [95% CI 0.584-0.760], p=0.011) and reduced composite outcome (B (95%CI): -0.251 (-0.455 - -0.046), p=0.017). No difference between IVUS or OCT was found. The PCI strategy (DES vs DCB), stent type, length or diameter were not predictors of outcomes. Conclusion In IRS PCI, the use of ICI compared to standard of care CA was associated with a reduction in all-cause mortality and composite outcome of CV mortality, culprit ISR PCI and ischemic stroke. The strategy of PCI differed with DES being used more frequently than DCB. No difference between IVUS or OCT was found.

Reduced trans-myocardial extraction of endothelin-1 in cardiac allograft vasculopathy

Abstract Introduction Cardiac allograft vasculopathy (CAV) is a major cause of graft failure due to microvascular dysfunction and ischaemia following heart transplant. Endothelin-1 (ET-1) is an endothelium derived vasoconstrictor peptide with multiple adverse effects including vascular smooth muscle proliferation and pro-inflammatory signalling. Elevated circulating ET-1 has been associated with accelerated CAV. We assessed the trans-myocardial gradient (TMG: coronary sinus minus coronary artery concentration: negative=extraction, positive=secretion) of ET-1 in heart transplant patients to determine correlations with angiographic, Intravascular Ultrasound (IVUS) and Optical Coherence Tomography (OCT) features of CAV. Methods 23 patients underwent invasive coronary angiography, 3-vessel grey scale IVUS (Opticross, 60mHz, Boston Scientific) and OCT (Dragonfly, Abbott Vascular) to define morphological features of vasculopathy 18±3 months post-transplant. Paired blood samples were obtained from the guide catheter and coronary sinus at the time of coronary imaging. Plasma was analysed using specific enzyme-linked immunosorbent assay for ET-1 peptide quantification. Survival was determined 98±5 months after initial assessment. Results ET-1 TMG distribution was mostly in the negative range reflecting net extraction across the coronary vascular bed (median [IQR]: -0.23 [-0.54, -0.02] pg/ml). However, vessels with more severe CAV demonstrated significantly more positive TMG i.e. less ET-1 trans-myocardial extraction (IVUS Stanford Grade IV: -0.05 [-0.21, 0.13] pg/ml versus Stanford Grade I-III: -0.31 [-0.64, -0.11] pg/ml, p = 0.01). ET-1 TMG was positively correlated with mean intimal thickness on both IVUS and OCT (IVUS: Kendall’s tau-b = 0.254, p=0.02 and OCT: Kendall’s tau-b = 0.344, p&amp;lt;0.0001). Patients who died had net ET-1 secretion compared with surviving patients (died: 0.21 [0.19 - 0.24] versus surviving: -0.28 [-0.52, -0.17], p = 0.01). Conclusions In heart transplant patients, coronary arteries with more intimal thickening had less trans-myocardial extraction, and more secretion of ET-1. ET-1 secretion in CAV may mediate the distal microvascular dysfunction commonly seen in this condition. These findings suggest a rationale for testing ET-1 receptor antagonists as a treatment for CAV.ET-1 TMG and IVUS Stanford Grade of CAVET-1 TMG and OCT derived MIT

Intravascular ultrasonography guided percuatneous coronary intervention with everolimus-eluting stents or bypass surgery for multivessel coronary artery disease: post-hoc analysis of the BEST study

Abstract Background Previous studies suggested that intravascular ultrasonography (IVUS)-guided percutaneous coronary intervention (PCI) improved clinical outcomes compared with coronary angiography (CAG)-guided PCI in complex coronary artery disease. Objectives We compared long-term clinical outcomes of IVUS-guided PCI with everolimus-eluting stent and coronary-artery bypass grafting (CABG) in multivessel coronary disease (MVD). Methods Among 880 patients with MVD enrolled in the BEST Extended Follow-up study, 333 patients underwent IVUS-guided PCI and 131 patients underwent CAG-guided PCI, which were compared with 401patients underwent CABG. The primary endpoint was the composite of death from any cause, myocardial infarction, or target-vessel revascularization during a median follow-up of 11.8 years (interquartile range, 10.6 to 12.5 years). Results During an extended follow-up, primary endpoint occurred in 75 patients (22.8%) in the IVUS-guided PCI group, in 58 patients (44.38%) in the CAG-guided PCI group, and in 95 patients (24.0%) in the CABG group. Compared with the CABG group, the IVUS-guided PCI group had a similar rate of primary endpoint (adjusted hazard ratio [HR], 1.013; 95% confidence interval [CI], 0.747-1.374; P=0.93), whereas the CAG-guided PCI group had a significantly higher risk of clinical events (adjusted HR, 2.231; 95% CI, 1.582-3.145; P&amp;lt;0.001). Similarly, whereas the IVUS-guided PCI group had similar rate (adjusted HR, 0.845; 95% CI, 0.605-1.181; P=0.324), the CAG guided PCI group had the significantly higher rate of the safety composite of death, stroke and myocardial infarction (adjusted HR, 2.016; 95% CI, 1.405-2.895; P&amp;lt;0.001) compared with the CABG group. However, both IVUS- and CAG-guided PCI groups had significantly higher rate of any repeat revascularization than CABG group. Conclusions In patients with MVD, IVUS-guided PCI appeared to be an safe and effective alternative to CABG. This study advocated the routine use of intravascular imaging during PCI for MVD.KM curve of outcomesPrimary and secondary outcome

Predictors of successful post-PCI optimization in vessels with post-PCI fractional flow reserve &amp;lt;0.90: findings from the FFR REACT trial

Abstract Introduction Recent studies demonstrated a strong relation between suboptimal post-PCI fractional flow reserve (FFR) and clinical outcome. The feasibility of post-PCI FFR optimization and its impact on future clinical outcome remains topic of debate. Purpose The aim of the present substudy of the FFR REACT trial was to identify predictors of 1) absolute FFR increase following optimization and 2) successful functional optimization (final FFR ≥0.90). Methods The FFR REACT trial was a single-center, investigator initiated, randomized controlled trial including patients with (un)stable angina or non-ST segment elevation myocardial infarction and angiographically successful PCI. Following a post-PCI FFR &amp;lt;0.90, patients were randomized to intravascular ultrasound (IVUS)-guided optimization according to a dedicated optimization protocol (intervention arm) or no further treatment (control arm). In case of PCI optimization, FFR and IVUS were repeated to evaluate the optimization result. The present analysis included all patients randomized to IVUS-guided optimization, who actually underwent PCI optimization, and who had pre- and post-optimization FFR values available. We performed multivariate linear and logistic regression models to identify predictors of absolute FFR increase and FFR ≥0.90 following optimization. Results A total of 145 patients were allocated to the IVUS-guided optimization arm with 152 vessels having a post-PCI FFR &amp;lt;0.90 (mean post-PCI FFR: 0.83±0.05), of which 104 vessels (68.4%) underwent additional treatment after IVUS evaluation. Paired FFR measurements (pre- and post-optimization) were available in 100/104 optimized vessels. The mean absolute change in FFR was 0.03±0.06 (p&amp;lt;0.001), and 20/100 (20%) vessels achieved a final FFR ≥0.90. Both left anterior descending arteries (LAD) (mean change = -0.033, 95%CI -0.055- -0.010, p=0.004) and higher post-PCI FFR values (mean change per 0.01 unit increase = -0.005, 95%CI -0.007 - -0.004, p&amp;lt;0.001) were associated with lower changes in FFR following optimization. Independent predictors of achieving a final FFR ≥0.90 were higher post-PCI FFR values (OR 1.26 per 0.01 unit increase, 95%CI 1.06-1.51, p=0.009) and non-LAD vessels (OR 5.72, 95%CI 1.73-18.94, p=0.004). Conclusions Within the FFR REACT trial, we observed that the likelihood of improvement in final FFR values was driven by the initial post-PCI FFR values (before optimization) and the location of the target vessel, with non-LAD lesion location being a significant predictor of FFR increase.

Drug coated balloon treatment with or without long inflation time in patients undergoing percutaneous coronary intervention: a propensity score matching analysis

Abstract Aim Although drug coated balloon (DCB) treatment for coronary de novo or in-stent restenosis lesions is a widespread strategy, consensus is lacking regarding appropriate DCB inflation time during percutaneous coronary intervention (PCI). We sought to evaluate the effect of long inflation time of DCB on procedural results and clinical outcomes after PCI. Methods Between January 2019 and August 2020, 314 consecutive patients with 445 lesions underwent intravascular imaging-guided PCI with paclitaxel DCB using different inflation time. In the entire cohort, the median follow-up duration was 966 days. We classified patients into DCB inflation time of ≥180 sec (prolonged group, n = 101) or &amp;lt;180 sec (standard group, n = 212). The primary clinical endpoint was a composite of death, myocardial infarction (MI), stroke, and target lesion revascularization. One-to-one propensity score matching was performed for potential bias. A total of 92 pairs were matched. Results In the matched population, the median age was 73 years, 82.1% was male, and 35.8% was treated for in-stent restenosis. The median duration of DCB inflation was 300 sec in the prolonged group and 60 sec in the standard group during PCI. After PCI, angiographic acute lumen gain was similar between the groups, but diameter stenosis was smaller in the prolonged group than in the standard group (30.0% vs. 33.5%, p = 0.042). Intravascular ultrasound (IVUS) analysis revealed that the prolonged group resulted in smaller plaque burden at the MLA (61.9% vs. 66.7%, p = 0.002), smaller area stenosis (66.6% vs. 69.4%, p = 0.044), and less mean increase in percent atheroma volume (-11.2 ± 7.1% vs. -7.4 ± 5.9%, p = 0.004). The rate of the primary clinical endpoint was lower in the prolonged group compared with the standard group (log-rank p = 0.025). The rate of IVUS dissection and hematoma and the incidence of periprocedural MI were not different among the 2 groups. Conclusions Despite comparable acute lumen gain, long DCB inflation time was associated with favorable angiographic and IVUS results and reduced adverse events compared with standard DCB treatment in patients with coronary artery disease.

Simultaneous, free-breathing, non-contrast 3D whole-heart coronary magnetic resonance angiography and vulnerable plaque imaging in patients with suspected acute coronary syndrome

Abstract Background Coronary artery high-risk plaque identified on cardiovascular magnetic resonance (CMR) is associated with future coronary events, independent of coronary artery luminal stenosis. We have recently developed a 3-dimensional whole-heart free-breathing non-contrast CMR sequence that allows for simultaneous high-resolution visualisation of the coronary arteries and vulnerable plaque on co-registered bright and black blood images (iT2prep-BOOST) with 100% respiratory scan efficiency. Objectives To validate iT2prep-BOOST in patients with non-ST-segment elevation myocardial infarction (NSTEMI) against the reference standard imaging modalities of invasive X-ray coronary angiography and intravascular imaging [optical coherence tomography (OCT)/intravascular ultrasound (IVUS)]. Methods 41 consecutive patients with suspected NSTEMI, based upon clinical history, electrocardiographic changes and positive high-sensitivity troponin assays, were recruited into the study. Invasive coronary angiography ± intravascular imaging was used to classify coronary segments into the following categories: normal, non-culprit and culprit segments; stenosed segments as well as segments with vulnerable plaque features (lipid, calcium, fibroatheroma, thin cap fibroatheroma (TCFA), plaque rupture and thrombus). The highest plaque/myocardial signal intensity ratio (PMR) in each coronary segment was analysed on iT2prep-BOOST. Results The mean iT2prep-BOOST acquisition time was 10.8 ± 1.3 minutes. The mean ± standard error of mean (SEM) PMR of culprit segments was significantly higher than non-culprit segments, which was significantly higher than normal segments (1.01 ± 0.05 vs. 0.67 ± 0.01 vs. 0.35 ± 0.01, P&amp;lt;0.001). Coronary segments with lipid, calcium and fibroatheroma had a significantly higher PMR compared to normal coronary segments (P&amp;lt;0.001) but lower than segments with TCFA, plaque rupture and thrombus (P&amp;lt;0.001). There was a progressive increase in PMR with increasing degree of coronary stenosis (P&amp;lt;0.001). Patients with type 2 diabetes, hypertension, hyperlipidaemia and family history of coronary artery disease had a significantly higher PMR on iT2prep-BOOST (P&amp;lt;0.001, P=0.02, P=0.04 and P=0.02 respectively). Finally, PMR was positively correlated with HbA1c, total cholesterol, non-HDL cholesterol, LDL cholesterol and triglyceride levels (P&amp;lt;0.001, P=0.02, P=0.02, P=0.05 and P=0.05 respectively). Conclusions In summary, the proposed iT2prep-BOOST framework has the potential to simultaneously acquire coronary artery angiography and to differentiate normal segments from non-culprit and culprit plaque segments. Furthermore, PMR is associated with both biochemical and patient related risk factors for coronary artery disease (CAD). The long-term prognostic value of PMR needs to be investigated in a longitudinal multi-centre study of patients with suspected CAD.Figure 1Figures 2 and 3

Clinical profile and incidence of 36-month cardiovascular events in patients with MINOCA: a regional registry of 126 patients in a tertiary cardiology hospital

Abstract Introduction Atherosclerotic plaque rupture is the main etiology of acute myocardial infarction (AMI). In 5% to 6% of AMIs, however, no obstructive lesions greater than 50% are observed, which are then classified as MINOCA (Myocardial Infarction with Non-obstructive Coronary Arteries).The paradigm of MINOCA as a benign condition has been revisited in recent years, as reduced survival rates and a higher risk of subsequent AMIs have been observed when compared to control groups. Purpose To describe the clinical profile and the risk of cardiovascular outcomes in patients diagnosed with MINOCA in a tertiary cardiology hospital between March 2000 and June 2022. Methods In this single-center cohort, all patients meeting the diagnostic criteria for MINOCA with (1) AMI, as follows: (a) no coronary stenosis ≥ 50% in any potential infarct-related artery; and (b) no other clinically overt specific cause for the acute presentation were evaluated with a median follow-up of 30(9.5-67.3) months. Information was obtained by medical chart. Sample characteristics were described in frequencies and median values(p25%-p75%). The incidence of a new cardiovascular event within 36 months after the MINOCA was estimated using the Kaplan-Meier method and the log-rank test applied to compare groups, accompanied by confidence intervals at 95% and an alpha of 5%(R 3.6.1 for MacOS). Results Of the 126 patients, 57.1% were women about 50 years of age (42.0-57.8). 20.6% had diabetes, 47.6% dyslipidemia, 60.3% hypertension and 20% a previous AMI. The predominant clinical presentation was NSTEMI (55.6%) (Table 1), and 7 patients had an episode of aborted sudden death during hospitalization. 38.1% of patients did not have an identified etiology. The most prevalent pathophysiological mechanism was plaque disruption (16.7%), followed by coronary thromboembolism (13.5%) and spontaneous coronary dissection (SCAD) (13.5%). Among the less frequent causes, we had vasospasm (7.1%) and myocardial bridge (2.4%). Only 3.2% underwent optical coherence tomography (OCT) or intravascular ultrasound (IVUS). No provocative testing was performed. 44.4% underwent cardiac magnetic resonance (CMR), within a median time to perform of 180.0 (60.0-707.5) days after the event. Regarding the discharged medical therapy, 79.4% had a beta-blocker and ACEI/ARB prescribed, 14.3% started anticoagulation and only 34.1% received DAPT. The incidence of a composite outcome (CV death, new AMI, stroke and cardiovascular hospitalization) at 36 months was 15% (CI95% 8.9%-24.6%)(Figure 2). The incidence of new MI was 6.3%(N=8), of stroke 2.4% (N=3), and of cardiovascular hospitalization 17.5%(N=22), with only one death. Conclusion The risk of the primary outcome in 36 months is worthy of note. Notably, most of the incidence was attributable to CV hospitalization. An important number of patients were discharged without a known etiology for their clinical presentation, and, consequentially, lacked individualized treatment.Figure 1.Outcomes

Predictors of periprocedural myocardial infarction after left main bifurcation percutaneous coronary intervention guided by optical coherence tomography imaging: the PREVENT study

Abstract Background PMI is one of the most common and relevant complications that occur after PCI, but it is still a matter of controversy. This clinical entity has been frequently correlated to peculiar plaque morphological features by several intravascular imaging studies. PCI of the LM coronary artery is a complex procedural setting, where the prognostic value of PMI is higher. Intravascular ultrasound (IVUS) has a traditional predominance in the guidance of LM-PCI, but optical coherence tomography (OCT) outperforms IVUS in spatial resolution and has affirmed itself as a strong support to PCI. Purpose The aim of this study is to identify preprocedural and postprocedural optical coherence tomography (OCT) findings potentially related to periprocedural myocardial infarction (PMI) in patients undergoing percutaneous coronary intervention (PCI) for non-ostial left main (LM) bifurcation disease. Methods We retrospectively analyzed 76 patients who underwent OCT before and after LM-PCI. Definitions of OCT findings were derived from expert consensus documents and major OCT studies. PMI was defined in accordance with the Academic Research Consortium-2 (ARC-2) definition. Results The presence of TCFA was found to be an independent predictor of PMI, and coherently a significantly higher lipid core arc was observed in the PMI group. Mean stent area was the only post-PCI feature to result significantly higher in the PMI group. Conclusions We found the presence of TCFA at pre-PCI OCT was an independent predictor of PMI. A higher mean stent area at post-PCI OCT in patients who developed PMI may suggest that aggressive stent expansion could not always be the right choice in such a context.

Trends and outcomes of intravascular imaging in patients undergoing percutaneous coronary intervention for coronary chronic total occlusion: a 5-year retrospective analysis

Abstract Background Elderly patients with coronary chronic total occlusions (CTO) represent a vulnerable population with comorbid conditions and complex coronary anatomy. Intracoronary imaging has become an important tool in the treatment of complex lesions with percutaneous coronary intervention (PCI). There is limited data on its impact in patients undergoing percutaneous coronary intervention (PCI) for coronary CTO. Purpose We aimed to identify the trends in utilization of intravascular ultrasound (IVUS) and optical coherence tomography (OCT) in patients undergoing single vessel (SV) - CTO PCI and its impact on clinical outcomes. Methods We queried the Nationwide Inpatient Sample database to identify hospitalizations for SV PCI between 2016 – 2020. Patients with CTO were identified using the ICD-10 diagnosis code. The use of IVUS and OCT was identified using the ICD-10 codes. We compared utilization of IVUS-OCT for SV-CTO PCI to those without and studied the impact of their utilization on clinical outcomes. The primary outcome was major adverse cardiovascular and cerebrovascular events (MACCE). Secondary outcomes included in-hospital mortality, re-infarction, stroke and post-procedural AKI. Outcomes were compared using univariate and multivariate logistic regression analysis. Results A total of 135,745 weighted hospitalizations for SV CTO-PCI were identified of which 13,610 (10%) utilized IVUS/OCT (mean age 66+/-12, 26.5 % females). Hospitalizations were stratified by patient age into a younger cohort &amp;lt;75 years (mean age 61 ± 9 years) and an older cohort ≥75 years (mean age 81 + 4). Male sex, Caucasians, and admissions to a large urban hospital were associated with higher IVUS/OCT use in both cohorts (p &amp;lt; 0.001). The use of IVUS/OCT was associated with significantly lower MACCE (aOR 0.73, 95% CI 0.6 - 0.8, p &amp;lt; 0.001) and lower incidence of re-infarction in both cohorts (OR 0.6, 95% CI 0.5-0.6, p&amp;lt;0.001 for both cohorts). In-hospital mortality was significantly lower in both cohorts utilizing intravascular imaging (OR 0.8, 95% CI 0.7-1.0, p&amp;lt;0.05 for age ≥75 years and OR 0.6, 95% CI 0.5-0.7, p &amp;lt;0.001) for age &amp;lt; 75). Overall, the rates of stroke and length of stay (4 + 5 days) were comparable but associated with higher hospitalization costs (153k-170k vs 110k-120k, p &amp;lt; 0.001). In patients undergoing CTO-PCI, there was an increasing trend towards the utilization of IVUS and OCT over the study period. Conclusion The use of IVUS/OCT guidance for CTO-PCI was associated with a significant reduction in MACCE, re-infarction and in hospital mortality regardless of age. There was a significant increase in the utilization of IVUS and OCT for the study period in all groups.

Antiplatelet therapy and prognosis at the onset of stent thrombosis

Abstract Background/Introduction Antiplatelet therapy is the standard therapy after stent implantation. Stent thrombosis (ST) has dramatically decreased by appropriate antiplatelet therapy and advancement in stent technology, but remains a life-threatening event if it occurs. Some patients develop ST even under intensive antiplatelet therapy (dual antiplatelet therapy; DAPT). The association of prognosis of ST and antiplatelet therapy at the onset of ST is unclear. Purpose We aimed to investigate the association of prognosis and antiplatelet therapy at the onset of ST. Methods We used the database of Long-term Outcomes following Occurrence of Stent Thrombosis registry, a multicenter, retrospective, observational study (Long ST registry). Definite ST cases from January 2008 to December 2017 were enrolled, and long-term clinical outcomes were investigated. Results A total of 187 patients (male: 86.1%, median age at the time of ST: 69.0) were eligible. Ninety patients were under DAPT at the onset of ST (DAPT group), whereas 97 patients were under single antiplatelet therapy or no antiplatelet therapy (non-DAPT group). The median follow-up duration was 1054.0 (inter-quartile range, 239.5 – 1850.0) days. Findings of intravascular ultra sounds at the time of ST were similar between two groups. Patients in DAPT group were independently associated with higher incidence of major adverse cardiac events (MACE: a composite of cardiovascular death, nonfatal myocardial infarction, and target lesion revascularization) than in non-DAPT group (adjusted hazard ratio: 2.36, 95% confidence interval [1.27 - 4.34], P value = 0.006). Conclusion Patients who developed ST under DAPT were independently associated with a higher incidence of MACE than patients under single or no antiplatelet therapy.

Abstract 15540: Comparative Outcomes of Femoropopliteal Intravascular Ultrasound Interventions: A Report From the XLPAD Registry

Background: Intravascular ultrasound (IVUS) during peripheral artery intervention is being increasingly used, however there is limited real-world procedural and outcomes data. Methods: We examined 4847 patients from the XLPAD Registry (NCT01904851) from 2006-2021 that underwent femoropopliteal (FP) endovascular intervention. The primary outcome was the incidence of major adverse limb events (MALE), which includes death, clinically driven revascularization, amputation, myocardial infarction (MI), and stroke. Comparative analyses were done between patients with IVUS and no IVUS interventions. Results: 322 (6.6%) patients underwent an IVUS guided FP intervention and 4525 without. Mean age 67, predominantly men (83% IVUS-group vs. 71% non-IVUS, p&lt;0.0001) and Caucasian (71% vs. 69%, p=NS). IVUS patients had worse risk profiles, with more smokers (59% vs. 47 %, p&lt;0.0001), heart failure (20% vs. 14%, p=0.006) and prior-MI (31% vs. 22%, p&lt;0.0001), and similar proportion of hypertensives, diabetics, dyslipidemics, or those with chronic kidney disease. IVUS patients had more multivessel intervention (2.4 vs. 1.9 lesions, p&lt;0.0001), SFA being the most common artery, followed by the popliteal artery in both groups. Balloon angioplasty was more common in the non-IVUS group (68% vs. 75%, p=0.005), whereas drug coated balloons (19% vs. 12%, p=0.005), drug-eluting stents (15 vs. 9%, p=0.001) and vascular mimetic stents (13 vs. 4%, p&lt;0.0001) were more frequent in the IVUS patients. Fluoroscopy time was longer in IVUS patients (35 min vs 30 min., p=0.005) with similar rates of procedural (90% vs. 93, p=NS) and technical success (94% vs. 95%, p=NS). There were no differences in peri-procedural complications, or 12-month MALE (21% vs. 20%, p=NS). Only death from any cause was significantly higher in the non-IVUS group (0.7 vs 3.0%, p=0.017). Conclusion: IVUS use is under 7% of all FP interventions in the XLPAD registry with IVUS guidance is used in patients with more adverse clinical risk profile, however with no difference in technical, procedural success and 12-month MALE events.

Abstract 14832: Comparative Effectiveness of Intravascular Ultrasound versus Angiography in Abdominal and Thoracic Endovascular Aortic Repair: Systematic Review and Meta-Analysis

Introduction: The effectiveness of intravascular ultrasound (IVUS) with angiography compared with angiography guidance alone in the treatment of aortic conditions remains unclear. Objective: This systematic review and meta-analysis evaluates the evidence for IVUS use during thoracic (TEVAR) and abdominal (EVAR) endovascular aortic repair. Methods: A comprehensive search of MEDLINE, EMBASE, and Cochrane CENTRAL databases was conducted to identify studies comparing outcomes of patients undergoing TEVAR/EVAR with and without IVUS. The primary outcome was all-cause mortality during follow-up. Secondary outcomes included contrast volume, fluoroscopy time, perioperative mortality, and reinterventions during follow-up. Continuous variables, risk ratios (RRs), and hazard ratios (HRs) with 95% confidence intervals (CIs) were extracted from each study. Pooled analysis was performed using a random-effects model. Results: A total of 6,888 patients (n=4,226 IVUS and n=2,662 non-IVUS) from nine observational studies were included in the meta-analysis. The follow-up period ranged from 9 months to 25 months. The IVUS group exhibited a reduction in contrast agent volume (weighted mean difference (WMD) [95% CI] = -34.65 mL [-54.73, -14.57]) and fluoroscopy time (WMD [95% CI] = -6.13 min [-11.10, -1.15]) ( Figure 1A&amp;B ). Perioperative mortality was comparable between both groups (RR [95% CI] = 0.67 [0.40-1.12], respectively). Reintervention rates and all-cause mortality during the follow-up period were similar between the two groups (HR [95% CI] = 0.80 [0.33-1.97], HR [95% CI] = 0.75 [0.47-1.18], respectively) ( Figure 1C ). Conclusions: This systematic review and meta-analysis provides evidence that the use of IVUS enables safe and effective deployment of TEVAR and EVAR with reduced contrast agent usage and shorter fluoroscopy duration. These findings support the potential of IVUS as a valuable tool in endovascular aortic interventions.