Cardiovascular diseases are the main cause of death worldwide, with coronary artery disease being the predominant underlying etiology. The most prevalent coronary lesions are represented by the atherosclerotic plaques, in more than 85% of cases, but there are several other non-atherosclerotic lesions such as spontaneous coronary artery dissection and/or hematoma and spontaneous recanalization of coronary thrombus, which are less common, approximately 5% of cases, but with similar clinical manifestations as well as complications. There are insufficient data regarding the pathological mechanism, true prevalence and optimal treatment of these kind of coronary lesions. Optical coherence tomography (OCT) is an intracoronary imaging technique, developed in order to overcome the diagnostic limitations of a standard coronary angiography and has an extremely high resolution, similar to that of a usual histological evaluation of a biopsy sample, thus, OCT provides a histological-like information, but in a in vivo environment. The aim of this article is to review the current knowledge regarding non-atherosclerotic coronary lesions, with an emphasis on the importance of OCT for optimal identification, characterization of pathogenic mechanisms and optimal treatment selection.

Multiple clinical trials have reported favorable outcomes after drug-coated balloon therapy for peripheral artery disease in above-the-knee and below-the-knee lesions and in both de novo and in-stent restenosis. However, there are still insufficient data to identify and tackle the risk factors associated with a higher risk of restenosis, which is the primary concern for patients who are treated with an endovascular approach. A modern armamentarium, which includes improved lesion preparation techniques such as plaque modification balloons, mechanical atherectomy, intravascular lithotripsy, and imaging, is crucial for obtaining better long-term clinical outcomes. Moreover, a better understanding of the molecular properties of drug-coated balloons has led to improved devices that could tackle the shortcomings of previous generations. This comprehensive review focuses on drug-coated balloon technology as a tool to treat peripheral artery disease and the effects of the molecular mechanisms involved in preventing vascular restenosis.

Background: The aim of this study was to evaluate the benefit of standard practice Optical Coherence Tomography (OCT) imaging, as a complement to coronary angiography (CA), for optimizing the indications, strategy, and results of percutaneous coronary interventions (PCI). Methods: We retrospectively analyzed 182 patients with OCT imaging in a single tertiary center. Results: OCT use had a low prevalence (3.1% of 4256 CAs and 1.7% of 3027 PCIs). OCT was used post-CA in 71.5% and post-PCI in 28.5% of cases, mainly in acute coronary syndromes—95.6%. OCT was performed for borderline lesions in 43.4% of cases; lesion severity was reassessed as severe and led to PCI in 64.5% of them. OCT was performed for nonsignificant lesions in 17% of cases; lesion severity was reassessed as severe and led to PCI in 38.7% of them. OCT provided optimal selection for PCI strategy in 11% of cases. OCT identified suboptimal PCI results in 54% left main PCIs and in 48% bifurcation PCIs with optimal CA; PCI optimization was performed. In the only seven patients with suboptimal PCI, OCT revealed an optimal result in four cases, thus avoiding unneccessary optimization. In 27.3% of patients with post-CA OCT and PCI result “systematic” OCT control, a PCI optimization was indicated. Conclusion: OCT supplied a major benefit in 86.2% of cases, especially by identifying significant coroanry stenosis in CA borderline and nonsignificant lesions; OCT led to PCI indication in two-thirds and, respectively, one-third of these cases. In the post-PCI context, OCT led to an indication of PCI optimization in half of the complex left main and bifurcation lesions, as well as in a quarter of “systematic” post-PCI OCT controls.

Background: There is a lack of a comprehensive picture of plaque geometry and composition of unstable atherosclerotic lesions as observed with intravascular ultrasound techniques.We analysed through a systematic review with meta‐analysis 39 characteristics of atherosclerotic plaques in three scenarios involving culprit and non‐culprit lesions from acute coronary syndromes vs stable angina pectoris patients, and culprit vs non‐culprit lesions in acute coronary syndromes patients.Methods: A systematic search of PubMed and EMBASE, from inception to April 2020 was performed. The combined odds ratios or mean differences of all IVUS characteristics were calculated with random‐effects models.Results: Twenty‐eight studies involving 5434 subjects, and 5618 lesions were included. Culprit lesions in acute coronary syndromes have larger plaque areas and remodeling indexes (MD = 0.13 [0.08; 0.17], p < 0.001) and contained larger necrotic cores (MD = 0.67 (95% CI 0.19;1.15), p = 0.006) that stable angina culprit lesions. In acute patients, culprit plaques were also more remodeled, had larger necrotic cores and had more frequently a Thin‐Cap Fibroatheroma morphology (OR = 1.79 (95% CI 1.21; 2.65), p = 0.004) than non‐culprit lesions. Non‐culprit lesions in acute syndromes were more often ruptured (OR = 2.25 (95% CI:1.05; 4.82), p = 0.037) or Thin‐Cap Fibroatheromas than in stable angina.Conclusion: Culprit lesions from acute coronary patients are larger, more positively remodeled and contained more lipids as compared to stable angina lesions or non‐culprit in acute patients. Non culprit lesions are also more often complicated or vulnerable in acute than stable patients.

The process of coronary calcification represents one of the numerous pathophysiological mechanisms involved in the atherosclerosis continuum. Optical coherence tomography (OCT) represents an ideal imaging modality to assess plaque components, especially calcium. Different calcification patterns have been contemporarily described in both early stages and advanced atherosclerosis. Microcalcifications and spotty calcifications correlate positively with macrophage burden and inflammatory markers and are more frequently found in the superficial layers of ruptured plaques in acute coronary syndrome patients. More compact, extensive calcification may reflect a later stage of the disease and was traditionally associated with plaque stability. Nevertheless, a small number of culprit coronary lesions demonstrates the presence of dense calcified plaques. The purpose of the current paper is to review the most recent OCT data on coronary calcification and the interrelation between calcification pattern and plaque vulnerability. How different calcified plaques influence treatment strategies and associated prognostic implications is of great interest.

Background: Patients with ST-segment elevation myocardial infarction (STEMI) and primary percutaneous coronary intervention (PPCI) on a left main culprit lesion have very high mortality rates. The interaction of chronic kidney disease (CKD) with such a catastrophic acute event on the background of their highly complex atherosclerotic lesions is not well established. Therefore, we sought to evaluate in these patients the influence of the estimated glomerular filtration rate (eGFR) on short- and long-term mortality. Methods: We retrospectively analyzed renal function in 81 patients with STEMI and PPCI on a left main culprit lesion from two tertiary centers. Results: Patients were divided in two groups according to an eGFR cut-off of 60 mL/min/1.73 m²: 40 patients with CKD and 41 without CKD. Patients with renal failure were older, had more diabetes, and had experienced more frequent myocardial infarction MIs. CKD patients had a higher baseline-SYNTAX score (p = 0.015), higher residual-SYNTAX score (p < 0.001), and lower SYNTAX revascularization index-SRI (p = 0.003). Mortality at 30-day, 1-year, and 3-year follow-ups were not significantly different between the two groups. However, when analyzed as a continuous variable, eGFR emerged as a predictor of 1-year mortality, both in univariate analysis (OR = 0.97, 95% CI: 0.95–0.99, p = 0.005) and in multivariate analysis, after adjusting for cardiogenic shock and Thrombolysis in Myocardial Infarction TIMI 0/1 flow (OR = 0.975, 95% CI: 0.95–0.99, p = 0.021). Conclusions: In STEMI with PPCI on a left main culprit lesion, renal failure was associated with more complex coronary lesions and less complete revascularization, and turned out to be an independent predictor of mortality at 1-year follow-up.