Optical detection of atherosclerosis at molecular level by optical coherence tomography: An in vitro study

There is an urgent need for contrast agents to detect the first inflammation stage of atherosclerosis by cardiovascular optical coherence tomography (CV-OCT), the imaging technique with the highest spatial resolution and sensitivity of those used during coronary interventions. Gold nanoshells (GNSs) provide the strongest signal by CV-OCT. GNSs are functionalized with the cLABL peptide that binds specifically to the ICAM-1 molecule upregulated in the first stage of atherosclerosis. Dark field microscopy and CV-OCT are used to evaluate the specific adhesion of these functionalized GNSs to activated endothelial cells. This adhesion is investigated under static and dynamic conditions, for shear stresses comparable to those of physiological conditions. An increase in the scattering signal given by the functionalized GNSs attached to activated cells is observed compared to non-activated cells. Thus, cLABL-functionalized GNSs behave as excellent contrast agents for CV-OCT and promise a novel strategy for clinical molecular imaging of atherosclerosis.

High-definition intravascular ultrasound: current clinical uses

Intravascular ultrasound (IVUS) provides grayscale images of the entire vessel wall, and its technology has recently been improved, resulting in more accurate tissue characterization. Compared with conventional IVUS, high-definition (HD) IVUS provides better resolution, better image quality, faster acquisition and integration of processing tools for more efficient cath lab workflow. HD-IVUS includes transducers with higher frequencies (≥ 45 MHz), allowing a higher near field resolution combined with enough tissue penetration for a more precise assessment of the entire vessel wall. HD-IVUS preserves the potential advantages of conventional (40 MHz) IVUS over optical coherence tomography by adding a substantially higher spatial resolution. For this reason, this technology has generated increasing interest among interventional cardiologists and researchers to provide better detailed morphological evaluation on complicated plaques in acute coronary syndrome patients and better stent optimization. In this review, we provide the state-of-the-art on this technology and its current clinical applications.

Overlapping versus single long stents in long chronic total occlusions: insights of the Iberian CTO Registry

BACKGROUND

It is unknown whether the availability of long drug-eluting stents modify the PCI strategy of long CTO. To describe the contemporary PCI strategy of long chronic total occlusions (CTO) using overlapping (OS) or single long stents (SS) and to analyze its results.

METHODS

2842 consecutive CTO PCIs were included. T hose with an occlusion length ≥20 mm in which ≥ 1 DES was implanted were analyzed. We compared procedural characteristics and clinical outcomes of CTO treated with OS or SS.

RESULTS

1088 CTO PCIs were analyzed (79.9% males; 64.7±10.6 years). Mean J-score was 2.8 ± 0.9. A SS was used in 38.5% of cases and OS in 61.5%. Total stent length was 64.1±29.9 mm; it was higher in the OS group (OS:79.9±25.5 mm vs SS:38.3±14.7 mm; p<0.0001). Mean number of stents in the OS group was 2.3±1. Very long stents (≥40 mm) were used in 27.4% of cases, more frequently in the OS group (OS:32.4% vs SS:19.3%; p<0.0001). After a mean follow-up of 19±15.9 months, the rate of adverse events (MACE) was 2% (cardiac death:1.6%, myocardial infarction:1.6%, target lesion revascularization:1.9% and stent thrombosis: 0.18%) with no significant differences between both groups. Overlapping was not an independent predictor of MACE.

CONCLUSIONS

In long CTO PCIs, OS is more frequently used than single stenting, especially in more complex procedures. Clinical outcomes at a mid-term follow-up are favorable. Using newer generation DES, overlapping was not an independent predictor of MACE, however a trend toward a higher event rate was observed in the OS group.

The double injection technique to improve visualization of severe coronary lesions with optical coherence tomography

BACKGROUND

Optical coherence tomography (OCT) is a high-resolution imaging modality that provides a precise evaluation of coronary anatomy. However, the presence of severe coronary lesions can prevent the required adequate distal contrast flushing resultting in inadequate blood clearance and poor image quality or complete blood shadowing of the underlying vessel wall.

OBJECTIVES

The aim of this prospective study was to evaluate the feasibility and safety of a novel "double injection technique" (DIT) to overcome the limitations of the conventional technique (CT) in patients with severely stenotic lesions.

METHODS

Twenty-three patients with severe angiographic lesions were sequentially imaged before intervention with OCT with the CT and then with DIT. A total of 5125 OCT frames were carefully matched and analyzed by an independent central core lab. A semiquantitative image quality score was used to grade the number of quadrants (0-4) with vessel wall visualization.

RESULTS

Optimal OCT visualization (Grades 3-4) significantly improved by the DIT (68% vs. 38% of frames, p < 0.001). The DIT also improved the mean score (3.1 ± 0.6 vs. 2.0 ± 0.8; p < 0.05; mean improvement of 1.1 ± 0.5 per patient). There were no complications associated with the DIT.

CONCLUSION

The DIT significantly improved preintervention image quality of OCT in severe coronary lesions.

Plaque modification in calcified chronic total occlusions: the PLACCTON study

INTRODUCTION AND OBJECTIVES

Severe calcification is present in> 50% of coronary chronic total occlusions (CTOs) undergoing percutaneous intervention. We aimed to describe the contemporary use and outcomes of plaque modification devices (PMDs) in this context.

METHODS

Patients were included in the prospective, consecutive Iberian CTO registry (32 centers in Spain and Portugal), from 2015 to 2020. Comparison was performed according to the use of PMDs.

RESULTS

Among 2235 patients, wire crossing was achieved in 1900 patients and PMDs were used in 134 patients (7%), requiring more than 1 PMD in 24 patients (1%). The selected PMDs were rotational atherectomy (35.1%), lithotripsy (5.2%), laser (11.2%), cutting/scoring balloons (27.6%), OPN balloons (2.9%), or a combination of PMDs (18%). PMDs were used in older patients, with greater cardiovascular burden, and higher Syntax and J-CTO scores. This greater complexity was associated with longer procedural time but similar total stent length (52 vs 57mm; P=.105). If the wire crossed, the procedural success rate was 87.2% but increased to 96.3% when PMDs were used (P=.001). Conversely, PMDs were not associated with a higher rate of procedural complications (3.7 vs 3.2%; P=.615). Despite the worse baseline profile, at 2 years of follow-up there were no differences in the survival rate (PMDs: 94.3% vs no-PMDs: 94.3%, respectively; P=.967).

CONCLUSIONS

Following successful wire crossing in CTOs, PMDs were used in 7% of the lesions with an increased success rate. Mid-term outcomes were comparable despite their worse baseline profile, suggesting that broader use of PMDs in this setting might have potential technical and prognostic benefits.

Clinical implications of arterial hypertension in patients with spontaneous coronary artery dissection

BACKGROUND

Spontaneous coronary artery dissection (SCAD) is a rare but increasingly recognized cause of acute coronary syndrome. Many patients with SCAD have associated coronary risk factors. However, the implications of arterial hypertension in SCAD patients remain unknown.

OBJECTIVE

This study sought to assess the clinical implications of arterial hypertension in a nationwide cohort of patients with SCAD.

METHODS

The Spanish SCAD registry (NCT03607981) prospectively enrolled 318 consecutive patients. All coronary angiograms were centrally analyzed to confirm the diagnosis of SCAD. Patients were classified according to the presence of arterial hypertension.

RESULTS

One-hundred eighteen patients (37%) had a diagnosis of arterial hypertension. Hypertensive SCAD patients were older (60 ± 12 vs. 51 ± 9 years old) and had more frequently dyslipidemia (56 vs. 23%) and diabetes (9 vs. 3%) but were less frequently smokers (15 vs. 35%) than normotensive SCAD patients (all P < 0.05). Most patients in both groups were female (90 vs. 87%, NS) and female patients with hypertension were more frequently postmenopausal (70 vs. 47%, P < 0.05). Hypertensive SCAD patients had more severe lesions and more frequently multivessel involvement (15 vs. 7%, P < 0.05) and coronary ectasia (19 vs. 7%, P < 0.05) but showed a similar prevalence of coronary tortuosity (34 vs. 26%, NS). Revascularization requirement was similar in both groups (17 vs. 26%, NS) but procedural success was significantly lower (65 vs. 88%, P < 0.05) and procedural-related complications more frequent (65 vs. 41%, P < 0.05) in SCAD patients with hypertension.

CONCLUSION

Patients with SCAD and hypertension are older, more frequently postmenopausal and have more coronary risk factors than normotensive SCAD patients. During revascularization SCAD patients with hypertension obtain poorer results and have a higher risk of procedural-related complications (NCT03607981).

Intracoronary thrombus assessment with cardiac computed tomography angiography in a deferred stenting strategy

Funding Acknowledgements

Type of funding sources: None.

Background.

Cardiac computed tomography angiography (CCTA) is precise in non-invasive coronary atherosclerosis characterization but its value in the diagnosis of intracoronary thrombus remains unknown. Therefore, our aim was to evaluate the diagnostic accuracy of CCTA for intracoronary thrombus and stenosis detection in acute coronary syndromes (ACS) with high thrombus burden selected for a deferred stenting (DS) strategy.

Methods.

We systematically performed a CCTA in consecutive DS patients 24 hours before the scheduled repeated coronary angiography that also included optical coherence tomography (OCT) imaging. Intracoronary thrombus and residual stenosis were blindly and independently evaluated by both non-invasive and invasive diagnostic tests. Agreement was determined per lesion using weighted Kappa (K) coefficient and  absolute intra-class correlation coefficient (ICC). A stratified analysis according to OCT-detected thrombus burden was also performed.

Results.

Thirty lesions in 28 consecutive patients with a large thrombus burden were analyzed. Concordance between CCTA and repeated coronary angiography in thrombus detection was good (K= 0.554; p&lt; 0.001), but both showed a poor agreement with OCT. CCTA needed &gt;11.5% thrombus burden on OCT to obtain adequate diagnostic accuracy. The lesions detected by angiography were more frequently classified as red thrombus (76.5 vs 33.3%; p= 0.087) on OCT. CCTA showed an excellent concordance with coronary angiography in diameter stenosis (ICC= 0.85; p&lt; 0.001), and was able to identify all the patients with severe residual stenosis.

Conclusion.

CCTA is able to assess intracoronary thrombus. Although CCTA showed just a good concordance with angiography in thrombus detection, the agreement in residual stenosis was excellent. Thus, in patients with a high-thrombus burden CCTA may substitute repeat angiography in patients considered for DS. Abstract Figure.

Procedural Results and One-Year Clinical Outcomes of Treatment of Bioresorbable Vascular Scaffolds Restenosis (from the RIBS VII Prospective Study)

Currently, both drug-eluting stents (DES) and drug-eluting balloons are recommended in patients with in-stent restenosis (ISR) of metallic stents. However, the clinical results of repeated interventions in patients with restenosis of bioresorbable vascular scaffolds (BVS) remain unsettled. We sought to assess the results of interventions in patients with BVS-ISR as compared with those obtained in patients with ISR of DES and bare-metal stents (BMS). Restenosis Intrastent: Treatment of Bioresorbable Vascular Scaffolds Restenosis (RIBS VII) is a prospective multicenter study (23 Spanish sites) that included 117 consecutive patients treated for BVS-ISR. Inclusion/exclusion criteria were similar to those of previous RIBS studies. Patients in the RIBS IV (DES-ISR, n = 309) and RIBS V (BMS - ISR, n = 189) randomized trials, were used as controls. Most patients with BVS-ISR were treated with DES (76%). Patients with BVS-ISR were younger, had larger vessels, and after interventions had higher in-segment residual diameter stenosis (19 ± 13%, 15 ± 11%, 15 ± 12%, p <0.001) than those treated for DES-ISR and BMS-ISR, respectively. At 1-year clinical follow-up (obtained in 100% of patients) target lesion revascularization (6%) was similar to that seen in patients with DES-ISR and BMS-ISR (8.7% and 3.7%, p = 0.32). Freedom from death, myocardial infarction, and target vessel revascularization (primary clinical end point) was 8.5%, also similar to that found in patients with DES-ISR and BMS-ISR (14.2% and 7.4%, p = 0.09). Results were also similar when only patients treated with DES in each group were compared and remained unchanged after adjusting for potential confounders in baseline characteristics. Time to BVS-ISR did not influence angiographic or clinical results. This study demonstrates the safety and efficacy of coronary interventions for patients presenting with BVS-ISR. One-year clinical results in these patients are comparable to those seen in patients with ISR of metallic stents (ClinicalTrials.gov ID:NCT03167424).

Coronary Endothelium-Dependent Vasomotor Function After Drug-Eluting Stent and Bioresorbable Scaffold Implantation

Background Early generation drug-eluting stents (DESs) showed a high grade of coronary endothelial dysfunction that was attributed to lack of stent reendothelialization. Endothelium-dependent vasomotor response of current DESs and bioresorbable scaffolds (BRSs) remains unknown. This study sought to assess the device-related endothelial function of current devices and to correlate neointima healing with endothelial function. Methods and Results A total of 206 patients from 4 randomized trials treated with the durable-polymer everolimus-eluting Xience (n=44), bioresorbable-polymer sirolimus-eluting Orsiro (n=35), polymer-free biolimus-eluting Biofreedom (n=24), bioactive endothelial-progenitor cell-capturing sirolimus-eluting Combo DES (n=25), polymer-based everolimus-eluting Absorb (n=44), and Mg-based sirolimus-eluting Magmaris BRS (n=34) underwent endothelium-dependent vasomotor tests and optical coherence tomography imaging, as per protocol, at follow-up. Crude vasomotor responses of distal segments to low-dose acetylcholine (10^-6 mol/L) were different between groups: bioresorbablepolymer DEShad the worst (-8.4%±12.6%) and durable-polymer DES had the most physiologic (-0.4%±11.8%; P=0.014). High-dose acetylcholine (10^-4 mol/L) showed similar responses between groups (ranging from -10.8%±11.6% to -18.1%±15.4%; P=0.229). Device healing was different between devices. Uncovered struts ranged from 6.3%±7.1% (bioresorbable-polymer DES) to 2.5%±4.5% (bioactive DES; P=0.056). In multivariate models, endothelium-dependent vasomotor response was associated with age, bioresorbable-polymer DES, and angiographic lumen loss, but not with strut coverage nor plaque type. Endothelial dysfunction (defined as ≥4% vasoconstriction) was observed in 46.6% of patients with low-dose and 68.9% with high-dose acetylcholine, without differences between groups. Conclusions At follow-up, endothelial dysfunction was frequently observed in distal segments treated with current stents without remarkable differences between devices. Although neointima healing was different between devices, poor healing was not associated with endothelial dysfunction.

Effect of PM2.5 on circulating inflammatory cells and microRNA expression in acute coronary syndrome

Background

Air pollutants increase the risk of myocardial infarction. Air pollution-induced atherosclerotic plaque destabilization may be related to inflammation, but the specific inflammatory alterations remain unclear.

Purpose

The aim of this prospective study was to assess the inflammatory changes in circulating immune cells and microRNAs in patients with acute coronary syndrome related to short-term exposure to PM2.5.

Methods

We prospectively included all consecutive patients admitted between March 2017 and July 2018 with the diagnosis of acute coronary syndrome (STEMI, NSTEMI, unstable angina) and coronary angiography in the acute phase of the disease. We also included a control group of patients with stable angina. For each patient we collected air concentrations of PM2.5 from the closest meteorological station to the patient residence obtaining the previous 24-hour average before hospital admission. All patients underwent systematic circulating inflammatory cell analysis. A selection of patients underwent miRNAs analysis.

Results

A total of 261 patients were included. According to PM2.5 exposure, 31 patients were selected for miRNA analyses. STEMI patients exposed to PM2.5 showed a reduction of CD4+ regulatory T (Treg) cells (Figure 1A). In the microRNA assessment, PM2.5 exposure was associated with higher circulating levels of let-7f-5p, miR-223-3p, miR-423-3p, miR-197-3p, miR-335–5, miR-376c-3p and miR-501-3p. Regarding clinical presentation, PM2.5 exposure in STEMI and NSTEMI patients was associated with an increase of miR-let-7f-5p, whereas miR-423-3p and miR-146a-5p were increased only in STEMI patients (Figure 1B).

Conclusions

STEMI related to PM2.5 short-term exposure is associated to specific changes involving CD4+CD25+Foxp3+ Treg cells and miR-146a-5p.

Funding Acknowledgement

Type of funding sources: Other. Main funding source(s): Ministerio de Ciencia e Innovaciόn; Fundaciόn BBVA Equipos de Investigaciόn Científica 2018 and from Caixa Banking Foundation; Sociedad Espanola de Cardiologia; Ministerio de Ciencia, Innovaciόn y Universidades, Carlos III Institute of Health-Fondo de Investigaciόn Sanitaria; Comunidad de Madrid; Fondo Europeo de Desarrollo Regional

Transcatheter aortic valve replacement using the new Evolut-Pro system: a prospective comparison with the Evolut-R device

Background

Evolut Pro (EVP) is a novel self-expandable aortic valve. This prosthesis consists of an external porcine pericardial wrap designed to reduce paravalvular leak (PVL), maintaining the benefits of its predecessor, the Evolut R (EVR). The aim was to compare the functional and clinical results in the short and medium term of the new EVP with the EVR system.

Methods

Consecutive patients receiving either the EVR (n=50) or the EVP (n=33) from June 2015 to October 2018 were compared. Baseline characteristics, cardiovascular imaging, procedural outcomes, short and mid-term follow-up outcomes were prospectively collected and assessed.

Results

Residual mild PVL was common and comparable in the two groups (EVR 79% vs. EVP 70%; P=0.4). In the EVR group, the presence of PVL was directly related to prosthesis size, but this correlation was not observed in the EVP group. Conduction abnormalities were more prevalent with the EVP, but these did not translate into a higher need of permanent pacemaker implantation. Vascular and bleeding complications were infrequent in both groups. At mid-term clinical follow-up (median survival time: EVR 11±0.3 months, EVP 12±0.2 months), the 1-year rate of adverse events was similar (EVR: 24%, EVP: 33%; P=0.3).

Conclusions

Both protheses are effective for the treatment of severe aortic stenosis with excellent results at mid-term clinical follow up. The EVP remains associated with a significant rate of residual mild PVL that appears to be similar to that observed with EVR.