and to reconstruct three-dimensional images of anatomic structures make it unique for the understanding of the congenitally malformed heart. real-time three-dimensional echocardiography can be used to guide the location of bioptomes during right ventricular endomyocardial biopsies, placement of catheter-delivered valvular devices, and in many other intraoperative assessments. three-dimensional echocardiography technology may feature anatomical intelligence, or the use of organ-modeling technology, to automatically identify anatomy based on generic models. all generic models refer to a dataset of anatomical information that uniquely adapts to variability in patient anatomy to perform specific tasks. built on feature recognition and segmentation algorithms, this technology can provide patient-specific three-dimensional modeling of the heart and other aspects of the anatomy, including the brain, lungs, liver, kidneys, rib cage, and vertebral column. contrast echocardiography contrast echocardiography or contrast-enhanced ultrasound is the addition of an ultrasound contrast medium, or imaging agent, to traditional ultrasonography. the ultrasound contrast is made up of tiny microbubbles filled with a gas core and protein shell. this allows the microbubbles to circulate through the cardiovascular system and return the ultrasound waves, creating a highly reflective image. there are multiple applications in which contrast-enhanced ultrasound can be useful. the most commonly used application is in the enhancement of lv endocardial borders for assessment of global and regional systolic function. contrast may also be used to enhance visualization of wall thickening during stress echocardiography, for the assessment of lv thrombus, or for the assessment of other masses in the heart. contrast echocardiography has also been used to assess blood perfusion throughout myocardium in the case of coronary artery disease. accreditation echocardiography can at many times be subjective, meaning that the person reading the echo may have personal input that affects the interpretation of the findings, leading to so-called "inter-observer variability", where different echocardiographers might produce different reports when examining the same images. it necessitated the development of accreditation programs around the world. the aim of such programs is to standardize the practice of echocardiography and to ensure that practitioners have the proper training prior to practicing echocardiography which will eventually limit inter-observer variability. europe at the european level individual and laboratory accreditation is provided by the european association of echocardiography (eae). there are three subspecialties for individual accreditation: adult transthoracic echocardiography (tte), adult transesophageal echocardiography (tee) and congenital heart disease echocardiography (chd). uk in the uk, accreditation is regulated by the british society of echocardiography. accredited radiographers, sonographers, or other professionals are required to pass a mandatory exam. united states the "intersocietal accreditation commission for echocardiography” (iac) sets standards for echo labs across the us. cardiologists and sonographers who wish to have their laboratory accredited by iac must comply with these standards. the purpose of accreditation is to maintain quality and consistency across echocardiography labs in the united states. accreditation is offered in adult and pediatric transthoracic and transesophageal echocardiography, as well as adult stress and fetal echo. accreditation is a two-part process. each facility will conduct a detailed self-evaluation, paying close attention to the iac standards and guidelines. the facility will then complete the application and submit actual case studies to the board of directors for review. once all requirements have been met, the lab will receive certification. iac certification is a continual process and must be maintained by the facility: it may include audits or site visits by the iac. there are several states in which medicare and/or private insurance carriers require accreditation (credentials) of the laboratory and/or sonographer for reimbursement of echocardiograms. there are two credentialing bodies in the united states for sonographers, the cardiovascular credentialing international (cci), established in 1968, and the american registry for diagnostic medical sonography (ardms), established in 1975. both cci and ardms have earned the prestigious ansi-iso 17024 accreditation for certifying bodies from the international organization for standardization (iso). accreditation is granted through the american national standards institute (ansi). recognition of ardms programs in providing credentials has also earned the ardms accreditation with the national commission for certifying agencies (ncca). the ncca is the accrediting arm of the national organization for competency assurance (noca). under both credentialing bodies, sonographers must first document completion of prerequisite requirements, which contain both didactic and hands-on experience in the field of ultrasound. applicants must then take a comprehensive exam demonstrating knowledge in both the physics of ultrasound and the clinical competency related to their specialty. credentialed sonographers are then required to maintain competency in their field by obtaining a certain number of continuing medical education credits, or cme's. in 2009, new mexico and oregon became the first two states to require licensure of sonographers. the american society of echocardiography (ase) is a professional organization made up of physicians, sonographers, nurses, and scientists involved in the field of echocardiography. one of the most important roles that the ase plays is providing their recommendations through the ase guidelines and standards, providing resource and educational opportunities for sonographers and physicians in the field. there have been various institutes who are working on use of artificial intelligence in echo but they are at a very early stage and still needs full development. terminology the most commonly used terminology in echocardiography diagnostics are: bsa – body surface area dt – deceleration time ivrt – isovolumic relaxation time la – left atrium ra – right atrium lv – left ventricle rv – right ventricle lvot – left ventricular outflow tract rvot – right ventricular outflow tract pht – pressure half time tapse – tricuspid annular plane systolic excursion vc – vena contracta edd – end diastolic diameter esd – end systolic diameter ivsd – interventricular septal end diastole pwd – posterior wall thickness lvmi – left ventricular mass index ao asc – ascending aorta st jxn – sinotubular junction lavi – left atrial volume index edv – end-diastolic volume esv – end-systolic volume ef – ejection fraction fs – fractional shortening ravi – right atrial volume index rvot – right ventricular outflow tract rvd – basal rv diameter ivc – inferior vena cava gls – global longitudinal strain rvsp – right ventricular systolic pressure e/a ratio