Discover the EACVI Textbook of Echocardiography 2nd edition
Chapter 5 Storage and report Steven Droogmans, Alessandro Salustri, and Bernard Cosyns Contents Storage 42 Report 43 Mandatory items 43 Recommended items 43 Findings and measurements 43 Comments and conclusions 44 References 45 Storage In recent years, many echocardiography labs have made the transition from analogue video recording towards digital acquisition and storage . Major advantages of digital storage (see % Box 5.1) are the improved image quality, lack of degradation over time (in contrast to video storage), side-by-side comparison of image loops, and post- processing of data for advanced two- (2D) and three-dimensional (3D) analyses (e.g. strain and volume) . Remote reviewing stations provide easy access to a patient study and facilitate quality control, multidisciplinary round-table discussions, and data analyses for investigational purposes. Acquisition time is also shortened by recording at least one, but preferably three, cardiac cycles compared to the storage of longer video loops. Despite the disadvantages of videotape storage, niche indications might remain when image loops have to be captured immediately with no time for loop selection. This might occur during emergency echocardiography, transoesophageal echocardiography, during intravenous saline or contrast administration, and especially when echo is performed during interventional procedures (e.g. transcatheter aortic valve implantation, patent foramen ovale closure, or MitraClip®). Longer acquisition loops with up to 2 minutes of real-time images are also possible on the latest generation of echo machines, completely obviating the need for the aforementioned videotape indication. Digital echocardiographic data are stored either locally on a hard disk or exchangeable media such as magneto-optical disks or even more frequently on DVDs. DVDs are easily obtainable and the cheapest solution. Data might also be periodically or directly transferred to network-attached storage systems which are becoming more frequent in hospital environments. These solutions have the same purpose, but differ considerably in memory capacity, retrieval speed, and cost. Back-up storage is also necessary for protecting against data loss and (network) stacks of identical copies of hard disks (RAID) need to be considered. In the early 1990s, the Digital Imaging and Communications in Medicine (DICOM) standard was developed allowing easier sharing of digital images between multivendor systems that otherwise used closed formats . However, in practice, several problems persist. For example, different types of ‘DICOM-compatible’ compressions are used, making it difficult to store and review data of different vendors into one universal system. By consequence, different (vendor-specific) storage servers and review software packages are often needed. The problems are usually solved with difficulty and need to be addressed and tested carefully when implementing network and storage systems from different vendors. Scientific societies and industry are working together in the Integrating Healthcare Enterprise (IHE) to address these issues. Ideally, the data of management of the echo laboratory should interface with other digital data management systems in the hospital (e.g. via Health Level 7 interface) to ensure that patient identity and examination data are uniformly registered.
Chapter 6 Transoesophageal echocardiography Frank A. Flachskampf, Mauro Pepi, and Silvia Gianstefani Contents Clinical indications and contraindications 46 Equipment 47 Competence 47 The examination 48 Patient preparation 48 Introduction of the probe 48 General course of the examination 48 Lower transoesophageal views 49 Upper transoesophageal views 50 Transgastric views 54 Aortic views 55 Three-dimensional examination 56 References 58 Clinical indications and contraindications Transoesophageal echocardiography (TOE) is a semi-invasive ultrasound imaging technique which uses the upper gastrointestinal tract to image cardiovascular structures, thus avoiding the problems for ultrasound imaging created by the thoracic ribcage and the lungs. It is indicated whenever transthoracic echocardiography is unable or unlikely to answer the clinical question. Its marked superiority in the diagnosis of left atrial thrombi, atrial septal pathology, endocarditic vegetations and abscesses, prosthetic valve dysfunction, and aortic pathology has made it a standard and indispensable technique which should be available in every echocardiographic laboratory as well as in every centre performing cardiac surgery [1,2]. In situations where transthoracic images are particularly difficult to obtain, such as in the ventilated patient, TOE may be used to obtain all information usually expected from transthoracic echo. Furthermore, valvular heart surgery is now routinely performed under intraoperative TOE monitoring. Several catheter-based interventional techniques for structural heart disease such as transcutaneous mitral repair, atrial septal defect closure, and others are further established indications for TOE guidance ; see % Box 6.1. Being a semi-invasive procedure, a small risk of harm to the patient and some discomfort in the awake patient have to be considered. Serious complications include oesophageal perforation (which may manifest with delay causing fever, neck pain, and subcutaneous emphysema), haemorrhage from oesophageal tumour, laryngospasm, and arrhythmias including cardiac arrest, but are very rare; mortality is about 1 in 10,000 [4,5]. The most frequent problem during introduction of the probe is entrapment of the tip in the piriform recess, resulting in an elastic obstruction and necessitating re-positioning; if substantial resistance to introduction or advancement of the probe is encountered, upper endoscopy should be performed prior to a new attempt. Death during or immediately after TOE has been reported in patients with acute aortic dissection and ascribed to a sudden surge in blood pressure due to the examination. Anticoagulation or thrombocytopenia raise the bleeding risk but are not strict contraindications. Sedation may lead to hypoxia and apnoea. Methaemoglobinaemia due to the topical anaesthetic agents prilocaine and benzocaine has been observed in rare instances . Infective endocarditis prophylaxis should not be given for TOE.