Influence of treatment modality and neointimal characteristics on optical coherence tomography on clinical outcomes of in-stent restenosis

Background

In-stent restenosis (ISR) represents the more frequent modality of stent failure. The currently recommended treatment strategies are represented by repeat drug-eluting stent (DES) implantation or drug-coated balloon (DCB) angioplasty. Optical coherence tomography can display important information regarding mechanisms of stent failure as well as neointimal characterization.

Purpose

Aim of the present study was to determine the impact of treatment modality (DES vs. DCB) as well as neointimal characteristics (homogeneous vs. non-homogeneous) as determined by intravascular OCT, on clinical outcomes and explore whether there is an interaction between neointimal pattern of ISR and treatment modality.

Methods

Patients presenting with ischemic symptoms and/or evidence of myocardial ischemia in three European centers and undergoing intravascular OCT prior to percutaneous coronary intervention (PCI) for ISR, were retrospectively included in this study. Characterization of neointimal tissue was performed at the frame displaying the maximal %AS as well as the 5 preceding and following analyzed frames. Each frame was subdivided in 4 quadrants (90°) and the neointimal characteristics separately characterized for each of them. Based on its optical characteristics, neointimal tissue was categorized as homogeneous, heterogeneous, layered or neoatherosclerosis.

Based on the dominant neointimal type, the study population was divided in two groups, (predominantly homogeneous and non-homogeneous). Primary endpoints of the study were represented by major adverse cardiac events (MACE) and its idividual components (death, cardiac death, myocardial infarction and target lesion revascularization (TLR)) at 2 years follow-up.

Results

A total of 197 patients undergoing OCT prior to PCI for ISR were included in this study. 100 patients were classified as having predominantly homogeneous and 97 as having predominantly non-homogeneous neointima.

No association was found between predominant OCT pattern (homogenous vs. non-homogenous) and MACE at 2 years follow-up (HR=1.01, 95% CI: 0.59–1.75; p=0.94), or the individual MACE components. Analogously, no significant differences in terms of MACE at 2 years were found between predominantly homogeneous vs. non-homogeneous neointima in the patient subgroup receiving a DES (p=0.10) and in that undergoing DCB treatment (p=0.11).

However, a significant interaction was found between neointimal tissue pattern and treatment modality in terms of MACE (p=0.02) aa well as death or MI (p=0.016). Predominantly non-homogeneous neointima in patients treated with DCB was associated with a higher incidence of MACE.

Conclusions

Our results indicate that there is a significant interaction between treatment modality of ISR (DES vs. DCB) and neointimal pattern as determined by intravascular OCT. These results land initial support to an OCT-guided treatment of ISR and should be confirmed by larger trials.

Funding Acknowledgement

Type of funding source: None

Severe coronary spasm in a COVID-19 patient

Myocardial injury is frequently detected in coronavirus disease 2019 (COVID‐19) patients. However, up to one‐third of COVID‐19 patients showing ST‐segment elevation on the electrocardiogram have angiographically normal coronary arteries. We present a case of an acute coronary syndrome due to a coronary spasm in a severe acute respiratory syndrome coronavirus 2 (SARS‐CoV‐2) patient. This pathophysiological mechanism was clearly demonstrated by intracoronary imaging techniques (optical coherence tomography) and invasive vasospasm test.

Renin-Angiotensin System Inhibition Following Transcatheter Aortic Valve Replacement

BACKGROUND

Several studies have demonstrated the benefits of transcatheter aortic valve replacement (TAVR) in patients with aortic stenosis, but the presence of persistent fibrosis and myocardial hypertrophy has been related to worse prognosis.

OBJECTIVES

The aim of this study was to explore the potential benefits of renin-angiotensin system (RAS) inhibitors on left ventricular remodeling and major clinical outcomes following successful transcatheter aortic valve replacement (TAVR).

METHODS

Patients from 10 institutions with severe aortic stenosis who underwent TAVR between August 2007 and August 2017 were included. All baseline data were prospectively recorded, and pre-specified follow-up was performed. Doses and types of RAS inhibitors at discharge were recorded, and matched comparison according to their prescription at discharge was performed.

RESULTS

A total of 2,785 patients were included. Patients treated with RAS inhibitors (n = 1,622) presented similar surgical risk scores but a higher rate of all cardiovascular risk factors, coronary disease, and myocardial infarction. After adjustment for these baseline differences, reduction of left ventricular volumes and hypertrophy was greater and cardiovascular mortality at 3-year follow-up was lower (odds ratio: 0.59; 95% confidence interval: 0.41 to 0.87; p = 0.007) in patients treated with RAS inhibitors. Moreover, RAS inhibitors demonstrated a global cardiovascular protective effect with significantly lower rates of new-onset atrial fibrillation, cerebrovascular events, and readmissions.

CONCLUSIONS

Post-TAVR RAS inhibitors are associated with lower cardiac mortality at 3-year follow-up and offer a global cardiovascular protective effect that might be partially explained by a positive left ventricular remodeling. An ongoing randomized trial will help confirm these hypothesis-generating findings. (Renin-Angiotensin System Blockade Benefits in Clinical Evolution and Ventricular Remodeling After Transcatheter Aortic Valve Implantation [RASTAVI]; NCT03201185).

Clinical and Angiographic Outcomes With Drug-Coated Balloons for De Novo Coronary Lesions: A Meta-Analysis of Randomized Clinical Trials

Background

The role of drug‐coated balloons (DCBs) in the treatment of de novo coronary lesions is not well established.

Methods and Results

Electronic databases and major conference proceedings were searched for randomized controlled trials that compared DCBs with stents or angioplasty for de novo coronary lesions. The primary outcome was target lesion revascularization. Summary estimates were conducted using random‐effects analysis complemented by several subgroup and sensitivity analyses. A total of 14 randomized controlled trials with 2483 patients were included. At a mean follow up of 12 months, DCBs were associated with no difference in the incidence of target lesion revascularization as compared with alternative strategies (risk ratio [RR], 0.79; 95% CI, 0.35–1.76). There was no difference in treatment effect based on the indication (ie, small‐vessel disease, myocardial infarction, bifurcation, or high bleeding risk) (P_interaction=0.22). DCBs were associated with lower target lesion revascularization compared with bare metal stents and similar target lesion revascularization compared with drug‐eluting stents (P_interaction=0.03). There was no difference between DCBs and control in terms of major adverse cardiac events, vessel thrombosis, or cardiovascular mortality. However, DCBs were associated with a lower incidence of myocardial infarction (RR, 0.48; 95% CI, 0.25–0.90) and all‐cause mortality (RR, 0.45; 95% CI, 0.22–0.94).

Conclusions

In patients with de novo coronary lesions, use of DCBs was associated with comparable clinical outcomes irrespective of the indication or comparator device. DCBs had a similar rate of target lesion revascularization compared with drug‐eluting stents. A randomized trial powered for clinical outcomes and evaluating the role of DCBs for all‐comers is warranted.

Spontaneous coronary artery dissection in Spain: clinical and angiographic characteristics, management, and in-hospital events

INTRODUCTION AND OBJECTIVES

Spontaneous coronary artery dissection (SCAD) is an uncommon cause of acute coronary syndrome. The characteristics and in-hospital clinical course of patients with SCAD in Spain remain unknown.

METHODS

We present data from consecutive patients included in the national prospective SCAD registry. Angiographic analysis was performed in a centralized core laboratory.

RESULTS

Between June 2015 and April 2019, we included 318 patients with SCAD (358 lesions) from 31 centers. Median age was 53 years, and 88% were women. The most frequent presentation was non-ST-segment elevation acute myocardial infarction (53%). The most frequently involved artery was the left anterior descending coronary artery (44%), predominantly affecting the distal segments (39%) and secondary branches (54%). Most lesions (62%) appeared on angiography as intramural hematoma, without double lumen. Conservative management was selected as the initial approach in most patients (78%). During the index admission, 6% of patients had a major adverse event and 4 patients (1.3%) died. Independent predictors of adverse events were initial management with percutaneous coronary intervention (OR, 5.97; P=.004) and angiographic presentation as intramural hematoma (OR, 4.96; P=.028).

CONCLUSIONS

In Spain, SCAD affects mainly middle-aged women. In most patients, the initial management strategy was conservative with excellent in-hospital survival. Initial management with percutaneous coronary intervention and angiographic presentation as intramural hematoma were related to the presence of in-hospital adverse events. Registered at ClnicalTrials.gov (Identifier: NCT03607981).

Correlation between fractional flow reserve and instantaneous wave-free ratio with morphometric assessment by optical coherence tomography in diabetic patients

Currently there is lack of data regarding the use of optical coherence tomography (OCT) to depict the hemodynamic relevance of coronary stenoses in diabetic patients. We sought to assess the diagnostic accuracy of OCT-derived morphologic assessment in identifying hemodynamically significant coronary lesions as determined by both, the resting instantaneous wave-free ratio (iFR) and the hyperemic fractional flow reserve (FFR) in diabetic patients. Diabetic patients presenting with at least one intermediate coronary lesion were prospectively and consecutively enrolled. All lesions were systematically assessed by iFR, FFR and OCT. A total of 41 intermediate lesions were analysed. Mean iFR and FFR values were 0.90 ± 0.04 and 0.81 ± 0.06, respectively (intra-class correlation coefficient 0.49; 95% CI 0.22-0.79). A moderate correlation between iFR and OCT derived minimal lumen diameter (MLD, r = 0.49) and minimal lumen area (MLA, r = 0.50) was found. Conversely, there was a poor correlation between FFR and OCT-derived MLD (r = 0.34) and MLA (r = 0.32). The diagnostic efficiency of MLA and MLD to identify iFR significant stenoses showed an AUC of 0.82 (95% CI 0.69-0.95) for MLD and 0.83 (95% CI 0.71-0.96) for MLA. A worse diagnostic efficiency was found when FFR was used as the reference with an AUC of 0.71 (95% CI 0.54-0.87) for MLD and 0.70 (95% CI 0.53-0.87). OCT-derived MLA and MLD were the strongest independent anatomic predictors of abnormal iFR and FFR values. In diabetic patients, OCT-derived MLA and MLD showed a moderate diagnostic efficiency in identifying functionally significant coronary stenoses by FFR or iFR. In diabetics, anatomic OCT measurements better predicted resting than FFR-determined physiologically significant lesions.

Plasmonic Copper Sulfide Nanoparticles Enable Dark Contrast in Optical Coherence Tomography

Optical coherence tomography (OCT) is an imaging technique affording noninvasive optical biopsies. Like for other imaging techniques, the use of dedicated contrast agents helps better discerning biological features of interest during the clinical practice. Although bright OCT contrast agents have been developed, no dark counterpart has been proposed yet. Herein, plasmonic copper sulfide nanoparticles as the first OCT dark contrast agents working in the second optical transparency window are reported. These nanoparticles virtually possess no light scattering capabilities at the OCT working wavelength (≈1300 nm); thus, they exclusively absorb the probing light, which in turn results in dark contrast. The small size of the nanoparticles and the absence of apparent cytotoxicity support the amenability of this system to biomedical applications. Importantly, in the pursuit of systems apt to yield OCT dark contrast, a library of copper sulfide nanoparticles featuring plasmonic resonances spanning the three optical transparency windows is prepared, thus highlighting the versatility and potential of these systems in light-controlled biomedical applications.

Spontaneous Coronary Artery Dissection: Mechanisms, Diagnosis and Management

Spontaneous coronary artery dissection (SCAD) is a relatively infrequent cause of acute coronary syndrome that usually affects young to middle-aged women. Mainly because of its low prevalence, until recently, most of the evidence on this condition was derived from case reports and small series. Over the last 5 years, more robust evidence has become available from larger retrospective and prospective cohorts of patients with SCAD. The increase in knowledge and recognition of this entity has led to the publication of expert consensus on both sides of the Atlantic. However, new data are continuously accumulating from larger cohorts of patients with SCAD, bringing new light to this little-understood condition. The aim of this article is to update the knowledge on SCAD, including new information from recent studies published since the consensus documents from the European Society of Cardiology and the American Heart Association.

Individual Lesion-Level Meta-Analysis Comparing Various Doses of Intracoronary Bolus Injection of Adenosine With Intravenous Administration of Adenosine for Fractional Flow Reserve Assessment

BACKGROUND

Intravenous infusion of adenosine is considered standard practice for fractional flow reserve (FFR) assessment but is associated with adverse side-effects and is time-consuming. Intracoronary bolus injection of adenosine is better tolerated by patients, cheaper, and less time-consuming. However, current literature remains fragmented and modestly sized regarding the equivalence of intracoronary versus intravenous adenosine. We aim to investigate the relationship between intracoronary adenosine and intravenous adenosine to determine FFR.

METHODS

We performed a lesion-level meta-analysis to compare intracoronary adenosine with intravenous adenosine (140 µg/kg per minute) for FFR assessment. The search was conducted in accordance to the Preferred Reporting for Systematic Reviews and Meta-Analysis statement. Lesion-level data were obtained by contacting the respective authors or by digitization of scatterplots using custom-made software. Intracoronary adenosine dose was defined as; low: <40 µg, intermediate: 40 to 99 µg, and high: ≥100 µg.

RESULTS

We collected 1972 FFR measurements (1413 lesions) comparing intracoronary with intravenous adenosine from 16 studies. There was a strong correlation (correlation coefficient =0.915; P<0.001) between intracoronary-FFR and intravenous-FFR. Mean FFR was 0.81±0.11 for intracoronary adenosine and 0.81±0.11 for intravenous adenosine (P<0.001). We documented a nonclinically relevant mean difference of 0.006 (limits of agreement: -0.066 to 0.078) between the methods. When stratified by the intracoronary adenosine dose, mean differences between intracoronary and intravenous-FFR amounted to 0.004, 0.011, or 0.000 FFR units for low-dose, intermediate-dose, and high-dose intracoronary adenosine, respectively.

CONCLUSIONS

The present study documents clinically irrelevant differences in FFR values obtained with intracoronary versus intravenous adenosine. Intracoronary adenosine hence confers a practical and patient-friendly alternative for intravenous adenosine for FFR assessment.