title: Optical coherence tomography of the pulmonary arteries: A systematic review.
abstract: Optical coherence tomography (OCT) is an imaging technique extensively used for visualizing the coronary circulation, where it assists clinical decision-making. Along with the new interventional procedures being introduced for pulmonary vascular disease, there is an increasing need for intravascular imaging of the pulmonary arteries. Additionally, measurements of the wall thickness of the pulmonary arteries of patients with various types of pulmonary hypertension (PH) may provide relevant diagnostic and prognostic information. The aim of this review is to summarize all the available evidence on the use of OCT for imaging the pulmonary bed and to describe a simple protocol for OCT image acquisition. We conducted a systematic review of the literature using electronic reference databases through February 2015 (MEDLINE, Cochrane Library, Web of Knowledge, and references cited in other studies) and the search terms "optical coherence tomography," "pulmonary hypertension," and "pulmonary arteries." Studies in which OCT was used to image the pulmonary vessels were considered for inclusion. We identified 14 studies reporting OCT imaging data from the pulmonary arteries. OCT was able to identify intravascular thrombi in patients with chronic thromboembolic PH (CTEPH), and an increase in vessel wall thickness was found in most patients with PH, compared with the controls. OCT has also been reported to be useful for the selection of balloon size in the setting of balloon pulmonary angioplasty for CTEPH. The main limitations include lack of standardization, little data on outcomes, cost, and the technical limitations involved in visualizing small-diameter (<1mm) pulmonary vessels. OCT has become a potential tool for the in vivo study of vascular changes in the pulmonary arteries, and may provide additional information in the assessment of patients with PH. Prospective high-quality studies assessing the safety, validity, and clinical impact of OCT imaging for pulmonary vessels are warranted.
authors.affiliation: Department of Cardiology, Hospitais da Universidade de Coimbra, Centro Hospitalar e Universitário de Coimbra, Coimbra, Portugal. Electronic address: elisabetejorge@gmail.com.
authors.forename: Elisabete
authors.initials: E
authors.lastname: Jorge
authors.affiliation: Department of Cardiology, Hospitais da Universidade de Coimbra, Centro Hospitalar e Universitário de Coimbra, Coimbra, Portugal; Faculty of Medicine, University of Coimbra, Coimbra, Portugal.
authors.forename: Rui
authors.initials: R
authors.lastname: Baptista
authors.affiliation: Department of Cardiology, Hospitais da Universidade de Coimbra, Centro Hospitalar e Universitário de Coimbra, Coimbra, Portugal.
authors.forename: João
authors.initials: J
authors.lastname: Calisto
authors.affiliation: Department of Cardiology, Hospitais da Universidade de Coimbra, Centro Hospitalar e Universitário de Coimbra, Coimbra, Portugal.
authors.forename: Henrique
authors.initials: H
authors.lastname: Faria
authors.affiliation: Department of Cardiology, Hospitais da Universidade de Coimbra, Centro Hospitalar e Universitário de Coimbra, Coimbra, Portugal; Faculty of Medicine, University of Coimbra, Coimbra, Portugal.
authors.forename: Pedro
authors.initials: P
authors.lastname: Monteiro
authors.affiliation: Department of Cardiology, Hospital Universitário Reina Sofia, Cordoba, Spain.
authors.forename: Manuel
authors.initials: M
authors.lastname: Pan
authors.affiliation: Department of Cardiology, Hospitais da Universidade de Coimbra, Centro Hospitalar e Universitário de Coimbra, Coimbra, Portugal.
authors.forename: Mariano
authors.initials: M
authors.lastname: Pêgo
mesh_terms: D000800:Angioplasty, Balloon; D006801:Humans; D011651:Pulmonary Artery / Q000000981:diagnostic imaging*; D011859:Radiography; D013923:Thromboembolism / Q000000981:diagnostic imaging; D041623:Tomography, Optical Coherence
keywords: Chronic thromboembolic pulmonary hypertension; Optical coherence tomography; Pulmonary arterial hypertension; Pulmonary artery; Pulmonary hypertension