Not All Plaque Erosions Are Equal

The Characteristics of Coronary Artery Lesions in COVID-19 Infected Patients With Coronary Artery Disease: An Optical Coherence Tomography Study

COVID-19 may predispose patients to cardiac injuries but whether COVID-19 infection affects the morphological features of coronary plaques to potentially influence the outcome of patients with coronary artery disease (CAD) remains unknown. By using optical coherence tomography (OCT), this study compared the characteristics of coronary plaque in patients with CAD with/without COVID-19 infection. The 206 patients were divided into 2 groups. The COVID-19 group had 113 patients between December 7, 2022, and March 31, 2023, who received OCT assessment after China decided to lift the restriction on COVID-19 and had a history of COVID-19 infection. The non-COVID-19 group had 93 patients without COVID-19 infection who underwent OCT before December 7, 2022. The COVID-19 group demonstrated a higher incidence of plaque ruptures (53.1% vs 38.7%, p = 0.039), erosions (28.3% vs 11.8%, p = 0.004), fibrous (96.5% vs 89.2%, p = 0.041) and diffuse lesions (73.5% vs 50.5%, p <0.001) compared with the non-COVID-19 group, whereas non-COVID-19 group exhibited a higher frequency of cholesterol crystals (83.9% vs 70.8%, p = 0.027), deep calcifications (65.6% vs 51.3%, p = 0.039) and solitary lesions (57.0% vs 34.5%, p = 0.001). Kaplan-Meier survival analysis revealed a significantly lower major adverse cardiac events-free probability in the COVID-19 group (91.6% vs 95.5%, p = 0.006) than in the non-COVID-19 group. In conclusion, OCT demonstrated that COVID-19 infection is associated with coronary pathological changes such as more plaque ruptures, erosions, fibrosis, and diffuse lesions. Further, COVID-19 infection is associated with a higher propensity for acute coronary events and a higher risk of major adverse cardiac events in patients with CAD.

Association between Eicosapentaenoic Acid to Arachidonic Acid Ratio and Characteristics of Plaque Rupture

AIMS

Eicosapentaenoic acid (EPA) has shown beneficial effects on coronary plaque stabilization. Based on our previous study, we speculated that EPA might be associated with the development of healed plaques and might limit thrombus size. This study aimed to elucidate the association between EPA and arachidonic acid (AA) ratios and various plaque characteristics in patients with plaque rupture.

METHODS

A total of 95 patients with acute coronary syndrome (ACS) caused by plaque rupture who did not take lipid-lowering drugs and underwent percutaneous coronary intervention using optical coherence tomography (OCT) were included. Clinical characteristics, lipid profiles, and OCT findings were compared between patients with lower and higher EPA/AA ratios (0.41) according to the levels in the Japanese general population.

RESULTS

In the high EPA/AA (n=29, 30.5%) and low EPA/AA (n=66, 69.5 %) groups, the high EPA/AA group was significantly older (76.1 vs. 66.1 years, P＜0.01) and had lower peak creatine kinase (556 vs. 1651 U/L, P=0.03) than those with low EPA/AA. Similarly, patients with high EPA/AA had higher prevalence of layered and calcified plaque (75.9 vs. 39.4 %, P＜0.01; 79.3 vs. 50.0 %, P＜0.01, respectively) than low EPA/AA group. Multivariate logistic regression analysis demonstrated that a high EPA/AA ratio was an independent factor in determining the development of layered and calcified plaques.

CONCLUSION

A high EPA/AA ratio may be associated with the development of layered and calcified plaques in patients with plaque rupture.

Superficial Calcified Plates Associated to Plaque Erosions in Acute Coronary Syndromes

This study investigates the clinical relevance and therapeutic implications of the OCT identification of intracoronary superficial calcified plates (SCPs) in acute coronary syndromes (ACSs). In 70 consecutive ACS patients (pts), we studied the three main underlying ACS mechanisms: plaque erosion (PE), plaque rupture and eruptive calcified nodule (CN). The PE lesions, occurring on an intact fibrous cap overlying a heterogeneous substrate, were identified in 12/70 pts (17.1%). PE on superficial calcified plates (PE-SCP) represented 58.3% of the PE lesions (7/12 pts) and had a 10% overall incidence in the culprit lesions (7/70 pts). PE-SCP lesions occurred mostly on the left anterior descending artery, correlated with white thrombi (85.7%) and had a proximal intraplaque site (71.4%). PE-SCP lesions were treated conservatively, as nonsignificant lesions, in 4/7 pts. Our study emphasizes that the coronary calcium-related ACS risk is not only associated with the spotty calcifications or CN but also with the PE-SCP lesions.

Distinctive Morphological Patterns of Complicated Coronary Plaques in Acute Coronary Syndromes: Insights from an Optical Coherence Tomography Study

Optical coherence tomography (OCT) is an ideal imaging technique for assessing culprit coronary plaque anatomy. We investigated the morphological features and mechanisms leading to plaque complication in a single-center observational retrospective study on 70 consecutive patients with an established diagnosis of acute coronary syndrome (ACS) who underwent OCT imaging after coronary angiography. Three prominent morphological entities were identified. Type I or intimal discontinuity, which was found to be the most common mechanism leading to ACS and was seen in 35 patients (50%), was associated with thrombus (68.6%; p = 0.001), mostly affected the proximal plaque segment (60%; p = 0.009), and had no distinctive underlying plaque features. Type II, a significant stenosis with vulnerability features (inflammation in 16 patients, 84.2%; thin-cap fibroatheroma (TCFA) in 10 patients, 52.6%) and a strong association with lipid-rich plaques (94.7%; p = 0.002), was observed in 19 patients (27.1%). Type III, a protrusive calcified nodule, which was found to be the dominant morphological pattern in 16 patients (22.9%), was found in longer plaques (20.8 mm vs. 16.8 mm ID vs. 12.4 mm SS; p = 0.04) and correlated well with TCFA (93.8%; p = 0.02) and inflammation (81.3%). These results emphasize the existence of a wide spectrum of coronary morphological patterns related to ACS.

In vivo detection of plaque erosion by intravascular optical coherence tomography using artificial intelligence

Plaque erosion is one of the most common underlying mechanisms for acute coronary syndrome (ACS). Optical coherence tomography (OCT) allows in vivo diagnosis of plaque erosion. However, challenge remains due to high inter- and intra-observer variability. We developed an artificial intelligence method based on deep learning for fully automated detection of plaque erosion in vivo, which achieved a recall of 0.800 ± 0.175, a precision of 0.734 ± 0.254, and an area under the precision-recall curve (AUC) of 0.707. Our proposed method is in good agreement with physicians, and can help improve the clinical diagnosis of plaque erosion and develop individualized treatment strategies for optimal management of ACS patients.

Morphological Characteristics of Eroded Plaques with Noncritical Coronary Stenosis: An Optical Coherence Tomography Study

AIMS

Recent studies suggested plaque erosion with noncritical stenosis could be treated distinctly from that with critical stenosis, but their morphological features remained largely unknown. The present study aimed to investigate morphological features of eroded plaques with different lumen stenosis using optical coherence tomography (OCT).

METHODS

A total of 348 ST-segment elevated myocardial infarction patients with culprit OCT-defined plaque erosion (OCT-erosion) were analyzed. Based on the severity of lumen area stenosis, all patients with OCT-erosions were divided into the following three groups: Group A (area stenosis ＜50%, n=50); Group B (50% ≤ area stenosis ＜75%, n=146); Group C (area stenosis ≥ 75%, n=152).

RESULTS

Compared with patients in Groups A and B, patients in Group C were older (p=0.008) and had higher prevalence of hypertension (p=0.029). Angiographic analysis showed that 72.0% of the eroded plaques in Group A were located in the left anterior descending artery, followed by 67.8% in Group B, and 53.9% in Group C (p=0.039). OCT analysis showed that Group A had the highest prevalence of fibrous plaques (p＜0.001) and nearby bifurcation (p=0.036), but the lowest prevalence of lipid-rich plaques (p＜0.001), macrophage accumulation (p＜0.001), microvessels (p=0.009), cholesterol crystals (p＜0.001), and calcification (p=0.023). Multivariable regression analysis showed fibrous plaque (odds ratio [OR]: 3.014, 95% confidence interval [CI]: 1.932-4.702, p＜0.001) and nearby bifurcation (OR: 1.750, 95% CI: 1.109-2.761, p=0.016) were independently associated with OCT-erosion with an area stenosis of ＜75%.

CONCLUSIONS

More than half of OCT-erosions presented with ＜75% area stenosis, having distinct morphological features from those of OCT-erosions with critical stenosis. Fibrous plaque and nearby bifurcation were independently associated with noncritically stenotic OCT-erosion, suggesting that eroded plaques might need individualized treatment.

Plaque Erosion: A Distinctive Pathological Mechanism of Acute Coronary Syndrome

Plaque erosion (PE) is one of the most important pathological mechanisms underlying acute coronary syndrome (ACS). The incidence of PE is being increasingly recognized owing to the development and popularization of intracavitary imaging. Unlike traditional vulnerable plaques, eroded plaques have unique pathological characteristics. Moreover, recent studies have revealed that there are differences in the physiopathological mechanisms, biomarkers, and clinical outcomes between PE and plaque rupture (PR). Accurate diagnosis and treatment of eroded plaques require an understanding of the pathogenesis of PE. In this review, we summarize recent scientific discoveries of the pathological characteristics, mechanisms, biomarkers, clinical strategies, and prognosis in patients with PE.

Predictors of Coronary Plaque Erosion in Current and Non-Current Smokers With ST-Segment Elevation Myocardial Infarction - An Optical Coherence Tomography Study

BACKGROUND

Smoking is an important risk factor of plaque erosion. This study aimed to investigate the predictors of plaque erosion in current and non-current smokers presenting with ST-segment elevation myocardial infarction (STEMI).

METHODS AND RESULTS

A total of 1,320 STEMI patients with culprit plaque rupture or plaque erosion detected by pre-intervention optical coherence tomography were divided into a current smoking group (n=715) and non-current smoking group (n=605). Plaque erosion accounted for 30.8% (220/715) of culprit lesions in the current smokers and 21.2% (128/605) in the non-current smokers. Multivariable analysis showed age <50 years, single-vessel disease and the absence of dyslipidemia were independently associated with plaque erosion rather than plaque rupture, regardless of smoking status. In current smokers, diabetes mellitus (odds ratio [OR]: 0.29; 95% confidence interval [CI]: 0.10-0.83; P=0.021) was negatively associated with plaque erosion as compared with plaque rupture. In non-current smokers, minimal lumen area (MLA, OR: 1.37; 95% CI: 1.16-1.62; P<0.001) and nearby bifurcation (OR: 3.20; 95% CI: 1.98-5.16; P<0.001) were positively related to plaque erosion, but not plaque rupture.

CONCLUSIONS

In patients with STEMI, the presence of diabetes mellitus significantly increased the risk of rupture-based STEMI but may not have reduced the risk of plaque erosion-based STEMI in current smokers. Nearby bifurcation and larger MLA were associated with plaque erosion in non-current smokers.

Association between apolipoprotein B/A1 ratio and coronary plaque vulnerability in patients with atherosclerotic cardiovascular disease: an intravascular optical coherence tomography study

Background

Apolipoprotein (Apo) A1 and Apo B are strongly associated with the risk of atherosclerotic cardiovascular disease (ASCVD). However, the relationship between the Apo B/A1 ratio and the morphology of coronary vulnerable plaques has not been fully elucidated in patients with ASCVD.

Methods

A total of 320 patients with ASCVD undergoing percutaneous coronary intervention were enrolled and assigned into acute coronary syndrome (ACS) or chronic coronary syndrome (CCS) group. The morphology of culprit plaque was analyzed by intravascular optical coherence tomography. Association between the Apo B/A1 ratio and coronary vulnerable plaques were evaluated using logistic regression models and receiver operator characteristic (ROC) curve analyses.

Results

The Apo B/A1 ratio was higher in ACS patients than CCS patients (0.77 ± 0.28 vs. 0.64 ± 0.22, P < 0.001) and it was also higher in patients with plaque rupture, erosion or thrombus than those without culprit plaques. The high Apo B/A1 ratio was associated with high percent of vulnerable plaques compared with low ratio group. The Apo B/A1 ratio was negatively related to fibrous cap thickness in lipid-rich plaque (r = − 0.228, P = 0.043). Univariate and multivariate logistic regression analyses revealed that the Apo B/A1 ratio was an independent factor of plaque rupture, erosion, and thrombus. The area under the ROC curve of the Apo B/A1 ratio for plaque rupture, erosion, and thrombus were 0.632, 0.624, and 0.670 respectively (P < 0.001 for all), which were higher than that of low-density lipoprotein cholesterol.

Conclusions

The Apo B/A1 ratio is an independent predictor for plaque rupture, erosion, and thrombus in patients with ASCVD.

Supplementary Information

The online version contains supplementary material available at 10.1186/s12933-021-01381-9.

Pancoronary Plaque Characteristics in STEMI Caused by Culprit Plaque Erosion Versus Rupture: 3-Vessel OCT Study

OBJECTIVES

This study sought to investigate nonculprit plaque characteristics in patients with ST-segment elevation myocardial infarction (STEMI) presenting with plaque erosion (PE) and plaque rupture (PR). Pancoronary vulnerability was considered at nonculprit sites: 1) the CLIMA (Relationship Between OCT Coronary Plaque Morphology and Clinical Outcome) study (NCT02883088) defined high-risk plaques with simultaneous presence of 4 optical coherence tomography (OCT) features (minimum lumen area <3.5 mm²; fibrous cap thickness [FCT] <75 μm; maximum lipid arc >180º; and macrophage accumulation); and 2) the presence of plaque ruptures or thin-cap fibroatheromas (TCFA).

BACKGROUND

PE is a unique clinical entity associated with better outcomes than PR. There is limited evidence regarding pancoronary plaque characteristics of patients with culprit PE versus culprit PR.

METHODS

Between October 2016 and September 2018, 523 patients treated by 3-vessel OCT at the time of primary percutaneous intervention were included with 152 patients excluded from final analysis.

RESULTS

Overall, 458 nonculprit plaques were identified in 202 STEMI patients with culprit PE; and 1,027 nonculprit plaques were identified in 321 STEMI patients with culprit PR. At least 1 CLIMA-defined OCT nonculprit high-risk plaque was seen in 11.4% of patients with culprit PE, but twice as many patients were seen with culprit PR (25.2%; p < 0.001). This proportion was also seen when individual high-risk features were analyzed separately. When patients with PE were divided by a heterogeneous substrate (fibrous or lipid-rich plaque) underlying the culprit site, the prevalence of nonculprits with FCT <75 μm, macrophages, and TCFA showed a significant gradient from PE_(Fibrous) to PE_{lipid-rich plaque (LRP)} to PR. Interestingly, nonculprit rupture was rarely found in patients with culprit PE_(Fibrous) (1.9%), although it was exhibited with comparable prevalence in patients with culprit PE_(LRP) (16.3%) versus PR (17.8%). Culprit PE predicted decreased pancoronary vulnerability independent of conventional risk factors.

CONCLUSIONS

STEMI patients with culprit PE have a limited pancoronary vulnerability that may explain better outcomes in these patients than in STEMI patients with culprit PR.

Macrophage infiltrates in coronary plaque erosion and cardiovascular outcome in patients with acute coronary syndrome

BACKGROUND AND AIMS

Plaque erosion (PE) is responsible for at least one-third of acute coronary syndrome (ACS), and inflammation plays a key role in plaque instability. We assessed the presence of optical coherence tomography (OCT)-defined macrophage infiltrates (MØI) at the culprit site in ACS patients with PE, evaluating their clinical and OCT correlates, along with their prognostic value.

METHODS

ACS patients undergoing OCT imaging and presenting PE as culprit lesion were retrospectively selected. Presence of MØI at culprit site was assessed. The incidence of major adverse cardiac events (MACEs), defined as the composite of cardiac death, recurrent myocardial infarction and target-vessel revascularization (TVR), was assessed [follow-up median (interquartile range, IQR) time 2.5 (2.03-2.58) years].

RESULTS

We included 153 patients [median age (IQR) 64 (53-75) years, 99 (64.7%) males]. Fifty-one (33.3%) patients presented PE with MØI and 102 (66.7%) PE without MØI. Patients having PE with MØI compared with PE patients without MØI had more vulnerable plaque features both at culprit site and at non-culprit segments. MACEs were significantly more frequent in PE with MØI patients compared with PE without MØI [11 (21.6%) vs. 6 (5.9%), p = 0.008], mainly driven by a higher risk of cardiac death and TVR. At multivariable Cox regression, PE with MØI was an independent predictor of MACEs [HR = 2.95, 95% CI (1.09-8.02), p = 0.034].

CONCLUSIONS

Our study demonstrates that among ACS patients with PE the presence of MØI at culprit lesion is associated with more vulnerable plaque features, along with a worse prognosis at a long-term follow-up.