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Background: Due to its high resolution, optical coherence tomography (OCT) is the most suitable modality for neointimal coverage assessments. Evaluation of stent healing seems crucial to accurately define their safety profile since delayed healing is connected with stent thrombosis. This study aimed to present an algorithm for automated quantitative analysis of stent strut coverage at the early stages of vessel healing in intravascular OCT. Methods: A set of 592 OCT frames from 24 patients one month following drug-eluting stent implantation was used to assess the algorithm's effectiveness. Struts not covered on any side or covered but only on one side were categorized as uncovered. The algorithm consists of several key steps: preprocessing, vessel lumen segmentation, automatic strut detection, and measurement of neointimal thickness. Results: The proposed algorithm proved its efficiency in lumen and stent area estimation versus manual reference. It showed a high positive predictive value (PPV) (89.7%) and true positive rate (TPR) (91.4%) in detecting struts. A qualitative assessment for covered and uncovered struts was characterized by high TPR (99.1% and 80%, respectively, for uncovered and covered struts) and PPV (77.3% and 87%). Conclusions: The proposed algorithm demonstrated good agreement with manual measurements. Automating the stent coverage assessment might facilitate imaging analysis, which might be beneficial in experimental and clinical settings.
RESUMO
Dual antiplatelet therapy (DAPT) is mandatory after percutaneous coronary intervention (PCI) with drug-eluting stent (DES) implantation, but optimal DAPT duration remains a topic of intense discussion. The shorter regimen of DAPT might be especially beneficial for high-bleeding-risk (HBR) patients. Novel stent platforms have been designed with innovations that should facilitate vessel healing following stent implantation and enable short DAPT. This review aimed to summarize evidence of the neointimal coverage of short-term stents and their implications for DAPT duration. Results from histological and optical coherence tomography (OCT) studies confirm the significant role of uncovered struts after the implantation of a stent in patients presenting with late stent thrombosis. Several studies have shown favorable vessel healing at one month (with 83.2% of covered struts, on average) and three months following stent implantation (with 93.3% of covered struts, on average). Solely HBR patient trials have proven that one month of DAPT can be applicable and safe in this population. Three-month DAPT was tested in a more diverse population and remains effective and safe in comparison to a longer DAPT regimen. That evidence proves that short-term DAPT might be applicable, especially for HBR patients.
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INTRODUCTION: Smoking is a wellestablished risk factor for cardiovascular diseases. However, in patients with STsegment elevation myocardial infarction (STEMI), smoking has been associated with better clinical outcomes; this phenomenon became known as the "smoker's paradox." OBJECTIVES: The aim of this study was to evaluate the association between smoking and clinical outcomes in STEMI patients treated with primary percutaneous coronary intervention (PCI), using 3 large national registries. PATIENTS AND METHODS: We retrospectively analyzed the data of 82 235 hospitalized STEMI patients treated with primary PCI. Among the analyzed population, 30 966 patients (37.96%) were smokers, and 51 269 (62.36%) were nonsmokers. We evaluated the baseline characteristics, pharmacotherapy, clinical outcomes, and readmission causes in a 36month followup. RESULTS: The smokers were significantly younger (median [interquartile range] age, 58 [52-64] vs 68 [59-77] years; P <0.001) than the nonsmokers, and there were more men in this group. The patients who smoked were less likely to have traditional risk factors, as compared with the nonsmokers. In the unadjusted analysis, inhospital and 36month mortality and rehospitalization rates were lower in the smokers group. However, after adjustment for baseline characteristics that differed between the 2 groups, the multivariable analysis showed that tobacco use was one of the independent risk factors for 36month mortality (hazard ratio, 1.11; 95% CI, 1.06-1.18; P <0.001). CONCLUSIONS: In the present largescale, registrybased analysis, the observed lower 36month crude rates of adverse events among the smokers, as compared with the nonsmokers, might be partially explained by a significantly lower burden of traditional risk factors and younger age of the smokers. After accounting for age and other baseline differences, smoking was found to be one of the independent risk factors for 36month mortality.
Assuntos
Intervenção Coronária Percutânea , Infarto do Miocárdio com Supradesnível do Segmento ST , Masculino , Humanos , Pessoa de Meia-Idade , Infarto do Miocárdio com Supradesnível do Segmento ST/cirurgia , Estudos Retrospectivos , Fumar/efeitos adversos , Fumar/epidemiologia , Fatores de Risco , Resultado do TratamentoRESUMO
BACKGROUND: Scientific statements recommend multimodality imaging in myocardial infarction with non-obstructive coronary arteries (MINOCA) to define the underlying cause. AIM: We evaluated the diagnostic yield of intravascular optical coherence tomography (OCT) and cardiac magnetic resonance (CMR) in the MINOCA setting. METHODS: In this prospective, single center, observational pilot study, we enrolled patients with MINOCA without previous coronary interventions. All patients underwent three vessel OCT, followed by CMR. Imaging results were combined to determine the mechanism of MINOCA, when possible. RESULTS: We enrolled 10 patients in this pilot study. Women constituted 50% of the analyzed population. The mean age of patients was 52 years. ST-segment elevation was found in 30% of patients. A possible culprit lesion was identified by OCT in 70% of participants, most commonly plaque rupture or erosion. An ischemic pattern of CMR abnormalities was identified in 70% of participants. Myocarditis and Tako-Tsubo were identified in 30%. A cause of MINOCA was identified in all patients using multimodality imaging, while using OCT alone identification occurred in only 70% of patients. CONCLUSION: In this pilot study, multimodality imaging with OCT and CMR identified potential mechanisms in all patients with a diagnosis of MINOCA, and it has the potential to guide medical therapy for secondary prevention.