Ifat Lavi

The incremental impact of residual SYNTAX score on long-term clinical outcomes in patients with multivessel coronary artery disease treated by percutaneous coronary interventions

To broaden the data supporting the use of the residual SYNTAX score (rSS) to define “reasonable” incomplete coronary revascularization (ICR) in order to improve the allocation of patients with severe coronary artery disease (CAD) to surgical/percutaneous revascularization and long‐term clinical outcomes.

Biomechanical factors in coronary vulnerable plaque risk of rupture: intravascular ultrasound-based patient-specific fluid-structure interaction studies.

ObjectivesThe aim of this study was to elucidate the mechanisms and underlying biomechanical factors that may play a role in the risk of rupture of vulnerable plaques (VPs) by studying patient-based geometries of coronary arteries reconstructed from intravascular ultrasound (IVUS) imaging utilizing fluid—structure interaction (FSI) numerical simulations. BackgroundAccording to recent estimates, coronary artery disease is responsible for one in six deaths in the USA, and causes about one million heart attacks each year. Among these, the rupture of coronary VPs followed by luminal blockage is widely recognized as a major cause of sudden heart attacks; most importantly, the patients may appear as asymptomatic under routine screening before the occurrence of the index event. Materials and methodsFSI simulations of patient-based geometries of coronary arteries reconstructed from IVUS imaging were performed to establish the dependence of the risk of rupture of coronary VP on biomechanical factors, such as the fibrous cap thickness, presence of microcalcification in the fibrous cap, arterial anisotropy, and hypertension. ResultsParametric FSI simulations indicated that mechanical stresses (von Mises stresses) increase exponentially with the thinning of the fibrous cap as well as with increasing levels of hypertension. The inclusion of a microcalcification in the fibrous cap considerably increases the risk of rupture of VP , with an ∼two-fold stress increase in the VP stress burden. Furthermore, the stress-driven reorientation and biochemical degradation of the collagen fibers in the vessel wall because of atherosclerosis (studied with an anisotropic fibrous cap 65° fiber reorientation angle) results in a 30% increase in the stress levels as compared with simulations with isotropic material models, clearly indicating that the latter, which are commonly used in such studies, underestimate the risk of rupture of VP. ConclusionThe results indicate that IVUS-based patient-specific FSI simulations for mapping the wall stresses, followed by analysis of the biomechanical risk factors, may be used as an additional diagnostic tool for clinicians to estimate the plaque burden and determine the proper treatment and intervention.

Fractional Flow Reserve Derived From Routine Coronary Angiograms

Pressure wire-based fractional flow reserve (FFR) has become the standard of reference for decision making regarding coronary revascularization. Deriving FFR from routine angiograms could facilitate the uptake of FFR-based clinical decisions. Several angiography-derived FFR methods have recently

Effect of coronary artery disease severity and revascularization completeness on 2-year clinical outcomes in patients undergoing transcatether aortic valve replacement.

AimsTo evaluate the effect of coronary artery disease (CAD) severity and completeness of revascularization on clinical outcomes following transcatheter aortic valve replacement (TAVR) using the SYNTAX score (SS), clinical SYNTAX score (cSS), and residual SYNTAX score (rSS). Methods and resultsWe studied 287 consecutive patients undergoing TAVR at our institution. Patients were classified as having CAD or no CAD and coronary patients were stratified according to SS and cSS. The completeness of revascularization was stratified using the rSS. We compared the 2-year outcomes according to SS/cSS/rSS. Forty-nine patients (17.1%) had CAD and sustained a higher rate of the primary endpoint at 2 years (28.3 vs. 16.1%, P=0.026). Stratified by CAD severity, the difference was driven by the high-severity groups (75.0 vs. 16.1%, P=0.002 for SS>22 and 41.2 vs. 16.1%, P=0.001 for cSS>63). Low-severity CAD patients did not have worse outcomes versus no CAD. When evaluating the effect of revascularization, patients with a rSS less than 8 did not have worse outcomes versus patients who did not have CAD. ConclusionIn patients undergoing TAVR, it is the severity of CAD (as assessed by the SS/cSS) that is associated with worse prognosis and not the mere presence of CAD. More complete revascularization attenuates the effect of CAD on clinical outcomes.

Validation Study of Image-Based Fractional Flow Reserve During Coronary Angiography

Background— Fractional flow reserve (FFR), an index of the hemodynamic severity of coronary stenoses, is derived from invasive measurements and requires a pressure-monitoring guidewire and hyperemic stimulus. Angiography-derived FFR measurements (FFRangio) may have several advantages. The aim of this study is to assess the diagnostic performance and interobserver reproducibility of FFRangio in patients with stable coronary artery disease. Methods and Results— FFRangio is a computational method based on rapid flow analysis for the assessment of FFR. FFRangio uses the patient’s hemodynamic data and routine angiograms to generate a complete 3-dimensional coronary tree with color-coded FFR values at any epicardial location. Hyperemic flow ratio is derived from an automatic resistance-based lumped model of the entire coronary tree. A total of 203 lesions were analyzed in 184 patients from 4 centers. Values derived using FFRangio ranged from 0.5 to 0.97 (median 0.85) and correlated closely (Spearman &rgr;=0.90; P<0.001) with the invasive FFR measurements, which ranged from 0.5 to 1 (median 0.84). In Bland–Altman analyses, the 95% limits of agreement between these methods ranged from −0.096 to 0.112. Using an FFR cutoff value of 0.80, the sensitivity, specificity, and diagnostic accuracy of FFRangio were 88%, 95%, and 93%, respectively. The intraclass coefficient between 2 blinded operators was 0.962 with a 95% confidence interval from 0.950 to 0.971, P<0.001. Conclusions— There is a high concordance between FFRangio and invasive FFR. The color-coded display of FFR values during coronary angiography facilitates the integration of physiology and anatomy for decision making on revascularization in patients with stable coronary artery disease. Clinical Trial Registration— URL: https://www.clinicaltrials.gov. Unique identifier: NCT03005028.

Intracoronary monocyte chemoattractant protein 1 and vascular endothelial growth factor levels are associated with necrotic core, calcium and fibrous tissue atherosclerotic plaque components: an intracoronary ultrasound radiofrequency study.

Aims: To investigate the relationship between various serum biomarkers and coronary atherosclerotic plaque composition obtained by intravascular ultrasound virtual histology (IVUS-VH). Methods: Using ELISA, we measured the serum levels of CD40 ligand, C-reactive protein, monocyte chemoattractant protein 1 (MCP-1), metalloproteinase 9, P-selectin and vascular endothelial growth factor (VEGF) in 40 patients with manifested coronary artery disease. Results: Correlation analysis between biomarkers levels, IVUS grayscale parameters and VH-defined necrotic core (NC), calcium, fibrous and fibrofatty components was performed. MCP-1 and VEGF levels correlated with the severity of area stenosis (r = 0.35, p = 0.03 and r = 0.38, p = 0.017, respectively) and inversely correlated with the remodeling index (r = –0.35, p = 0.03 and r = 0.35, p = 0.02, respectively). Higher levels of MCP-1 were associated with increased calcium (r = 0.47, p = 0.004), NC (r = 0.38, p = 0.02) and less fibrous tissue components (r = –0.34, p = 0.03), whereas VEGF had an inverse correlation with both calcium components (r = –0.37, p = 0.02) and NC (r = –0.34, p = 0.036) but was strongly associated with increased fibrous components (r = 0.47, p = 0.003). No significant correlation was noted for any of the other biomarkers. Conclusions: MCP-1 and VEGF serum levels in patients with ischemic heart disease are correlated with coronary artery plaque burden and composition.

Transcatheter aortic valve implantation of a CoreValve device using novel real-time imaging guidance☆

Thorough imaging of the aortic valve and related structures is highly important before and during transcatheter aortic-valve implantation. However, conventional aortography is limited for guiding precise valve placement and depends on contrast injections. A real-time imaging system capable of guiding the operator during Edwards-SPAIEN valve procedures has been introduced (C-THV, Paieon, Inc.). We describe the first application of the novel C-THV system during CoreValve implantation in a very challenging clinical scenario that required precise high implantation using minimal contrast.

Long-term outcomes of patients with complex coronary artery disease according to agreement between the SYNTAX score and revascularization procedure in contemporary practice.

AimsThe SYNTAX score (SS) has been shown to identify subgroups of patients with left main or triple-vessel coronary artery disease (LM/3VCAD) that can be treated with a percutaneous coronary intervention (PCI) with equal clinical outcomes as coronary artery bypass surgery (CABG).We sought to assess the adequacy of referral to PCI/CABG of patients with LM/3VCAD at our institution. Patients and methodsWe retrospectively matched all patients with LM/3VCAD referred to CABG (n=145) to patients referred to PCI in our institution during 2009–2010. We calculated the SS and clinical SS (cSS) according to the European Society of Cardiology guidelines and compared the agreement rates between the revascularization modality and the SS as well as clinical outcomes at the 3-year follow-up. ResultsThe overall agreement rates between the revascularization procedure and the SS was 67%, for example the rate was higher in patients referred to PCI compared with CABG (78 vs. 49%) and patients with 3VCAD compared with patients with LMCAD (68 vs. 51%). Patients without agreement between the revascularization modality and the SS had higher rates of combined adverse cardiac events (42.6 vs. 27% P=0.008). Similar results were observed when using the cSS at different cutoff levels. ConclusionAt our institution, there was considerable disagreement between a clinical judgment-based coronary revascularization and the SS/cSS-based allocation process as to the preferred revascularization modality for patients with complex CAD. Our results suggest that integrating the SS/cSS into the decision-making process for assigning patients to revascularization would yield better clinical outcomes.

C-THV measures of self-expandable valve positioning and correlation with implant outcomes

Accurate positioning of the valve device during transcutaneous aortic valve implantation (TAVI) is of crucial importance. The Paieon C‐THV navigation system has been designed to correctly guide device deployment during TAVI.

Necrotic core and thin cap fibrous atheroma distribution in native coronary artery lesion-containing segments: a virtual histology intravascular ultrasound study.

ObjectivesThe aim of this study was to assess the longitudinal topographical relationships between minimal luminal area (MLA) sites and plaques with the most vulnerable characteristics using radiofrequency-based virtual histology intravascular ultrasound analysis. MethodsWe analyzed 69 native coronary artery segments with de-novo lesions (>50% stenosis) obtained from 50 patients with ischemic coronary artery disease. Maximal necrotic core (maxNC) was defined as a virtual histology intravascular ultrasound frame with the maxNC area and virtual histology-characterized thin cap fibrous atheroma was defined as a cross-section, which contained a plaque burden of more than 40%, relative necrotic core area of 10% or more, and a narrow band encircling the lumen containing relative necrotic core area of more than 10%, in three consecutive frames. ResultsMaxNC was present at the MLA site in only 17.4% of the segments, proximal in 52.2% (by 5.0±5.4 mm), and distal to MLA in 30.4% (by 4.0±5.1 mm). Non-MLA sites with maxNC (n=57) compared with MLA sites had reduced plaque burden (64.5±11.2% vs. 76.0±10.5%, P<0.001), increased remodeling index (1.04±0.17 vs. 0.89±0.15, P<0.001), less fibrotic tissue (47.7±13.4% vs. 54.8±13.8%, P<0.001), and higher dense calcium deposition (15.3±10.8% vs. 11.9±10.3%, P<0.001). Plaques containing maxNC and virtual histology-characterized thin cap fibrous atheroma were found in 23 of the non-MLA sites compared with two of the MLA sites (P<0.0001). ConclusionsIn coronary artery segments with intermediate-to-severe stenosis, plaques containing maxNC are mostly located away from the MLA site and more often comprise virtual histology-characterized thin cap fibrous atheroma. Such data may carry practical implications for coronary revascularization procedures.