American College of Cardiology

Quinones ET AL., ACC/AHA CLINICAL COMPETENCE STATEMENT ON ECHOCARDIOGRAPHY
J Am Coll Cardiol 2003;41:687-708

ACC/AHA Clinical Competence Statement on Electrocardiography and Ambulatory Electrocardiography

A Report of the American College of Cardiology/American Heart
Association/American College of Physicians–American Society of Internal Medicine Task Force on Clinial Competence

III. Transthoracic Echocardiography in Adult Patients

Overview and Indications for the Procedure. Transthoracic two-dimensional and Doppler echocardiography is one of the most important and frequently performed diagnostic procedures for patients with cardiovascular disease. It provides highly accurate diagnostic information regarding the anatomy and physiology of the cardiac chambers, valves, major vessels, and pericardium in a noninvasive and instantaneous manner. This information can immediately affect the further diagnostic work-up for the patient, dictate therapeutic decisions, determine response to therapy, and predict patient outcome. Because transthoracic two dimensional/Doppler echocardiography plays such a major role in the care of patients with suspected or known cardiovascular diseases, the widely accepted indications for the procedure span the breadth of cardiovascular medicine, including but not limited to the diagnosis of and guiding treatment for: coronary artery disease, valvular heart disease, heart failure, hypertensive heart disease, congenital abnormalities, complications of pulmonary disease, tumors/masses, cardiac trauma, pericardial disease, and others. Details of accepted indications have been recently revised (ACC/AHA Guidelines revision, publication pending). This section will discuss the cognitive requirements, training, proof of competence, and maintenance of competence for performance and/or interpretation of TTE in adult patients with acquired diseases and/or simple congenital heart defects. A separate section is dedicated to the use of echocardiography in pediatric patients and adults with complex congenital defects, as defined by the Task Force 1 Report from the 32nd Bethesda Conference on "Care of the Adult with Congenital Heart Disease".⁵ Simple lesions are listed in Table 3.

Minimum Knowledge Required for Performance and Interpretation (Table 4). Competence in performing and/or interpreting TTE in adult patients requires all of the basic knowledge of ultrasound physics, of instrumentation, and of cardiac anatomy, physiology and pathology described in the section on General Principles. Transducer manipulation is perhaps the most difficult and underestimated skill set to master when performing a transthoracic echocardiographic examination. It is the most important factor in obtaining optimal image quality in standard tomographic imaging planes and optimal Doppler flow velocity signals. As previously mentioned, appropriate knowledge of ultrasound instrument settings such as depth, gain, time-gaincompensation, dynamic range, filtering and display of received signals is essential for performing an optimal examination. Even though the majority of echocardiographic examinations are performed by sonographers and interpreted by physicians in most clinical settings in the United States, all physicians interpreting scans are required to be skilled in echocardiographic data acquisition as well. This facilitates the physician's understanding of optimal echocardiographic data acquisition and technical quality. Physicians who are ultimately responsible for the diagnostic data should play an appropriate role in quality control and teaching in the sonographer-physician relationship. The echocardiographic physician should accordingly be available for consultation with the sonographer. Furthermore, a physician properly trained in echocardiographic data acquisition should be able to perform emergency bedside echocardiographic examinations when a sonographer is not available.

Training Requirements (Table 5). Training in adult TTE remains intimately linked to training in other aspects of adult cardiovascular medicine, including cardiovascular catheterization, inpatient and outpatient clinical care, electrocardiography, pacing and electrophysiology, cardiac surgery, and other noninvasive imaging. The number of procedures required to accomplish clinical competence in twodimensional Doppler echocardiography is, in reality, somewhat arbitrary because there is individual variation in cognitive, analytical, and manual-dexterity skills. Furthermore, the breadth of the clinical experience is equally as important as the numbers themselves, in that supplemental training may be required in centers where patient populations are skewed by specific referral patterns. It is important to emphasize that the numbers of examinations refer to comprehensive two-dimensional and Doppler echocardiographic studies that are diagnostic, complete, and quantitatively accurate.

The numbers set forth in this document reflect the minimum requirements for the average trainee engaged in a training program in adult cardiovascular medicine. These numbers have been revised specifically to reflect the reality of mainstream training programs in cardiovascular medicine in the current era. A new distinction has been made between the performance of echocardiograms and interpretation of echocardiograms. Expert consensus remains that all physicians involved in the practice of the subspecialty of cardiovascular medicine or who participate in interpreting echocardiograms must be trained at a minimum level in performing echocardiograms (Table 5).

Level 1 Training (3 months, 75 examinations performed, 150 examinations interpreted). Level 1 is defined as the minimal introductory training that must be achieved by all trainees in adult cardiovascular medicine. This includes a basic understanding of the physics of ultrasound, the fundamental technical aspects of the examination, cardiovascular anatomy and physiology as it relates to echo and Doppler imaging, and recognition of simple as well as complex cardiac pathology and pathophysiology. Level 1 trainees are required to train in echocardiography for a minimum of three months and perform and interpret a minimum of 75 two-dimensional and Doppler TTEs, and interpret an additional 75 two-dimensional and Doppler TTEs (total of 150 exams interpreted). This nominal hands-on training should enable a physician to expand on or clarify the data acquired by a sonographer, and to understand potential technical limitations and artifacts. Level 1 training is not sufficient for a trainee to perform or interpret echocardiograms independently.

Level 2 Training (6 months, 150 examinations performed [75 additional] and 300 interpreted [150 additional]. Level 2 training is the minimum recommended training for a physician to perform and interpret echocardiograms independently. These requirements are specifically for transthoracic two-dimensional and Doppler echocardiography. Level 2 is defined as a minimum of an additional 3 months of training in echocardiography (6 months cumulative) and the addition of 150 transthoracic two-dimensional and Doppler examinations interpreted (300 cumulative exams interpreted). Additional training in special procedures, such as TEE and stress echocardiography, is detailed subsequently in this document. Although some experience in special procedures may be attained as a part of Level 2 training, in most instances, full competence in these areas will require additional training beyond Level 2.

Level 3 Training (12 months, 300 transthoracic twodimensional and Doppler echocardiograms performed [150 additional] and 750 interpreted [450 additional]). Level 3 represents a high level of expertise that would enable an individual to serve as a director of an echocardiography laboratory and be directly responsible for quality control and for the training of sonographers and physicians in echocardiography. Although these guidelines reflect the minimum number of TTE and Doppler studies, most physicians who are Level 3-trained will also have additional training in TEE and stress echocardiography. It should be emphasized that these numbers reflect the minimum examinations considered for clinical competence; many training programs will offer a greater experience in interpretation of transthoracic echocardiograms over the time periods previously outlined.

Physicians who trained in Cardiovascular Disease before July 1990 (when the Level 1 to 3 guidelines were adopted) are considered clinically competent for independent performance and interpretation if they have either the equivalent of Level 2 training, as previously set forth, or have the experience of providing echocardiographic services for a minimum of 400 examinations performed and/or interpreted per year for a minimum of 3 years. Physicians who completed training in Cardiovascular Disease between July 1990 and July 1998 are considered clinically competent in echocardiography with the equivalent of Level 2 training, as previously set forth, if they completed 3 months training in echocardiography with performance and interpretation of 150 transthoracic echocardiograms, and have provided echocardiographic services of a minimum of 400 echo and Doppler examinations per year for a minimum of 2 years. Physicians who completed training in Cardiovascular Disease after July 1998 can be considered clinically competent in echocardiography with 6 months of training, a minimum of 150 examinations performed and a total of 300 examinations interpreted.

Proof of Competence (Table 6). The optimal evaluation of clinical competence is performed by an individual or individuals who observe the trainee directly. This is usually accomplished by the director of the echocardiography laboratory or by qualified faculty who participate in the training activities of the laboratory. Trainees are strongly encouraged to maintain a log with counts of all performed and interpreted echocardiograms that should be updated regularly. A letter or certificate from either the supervising echocardiography laboratory director or the training program director, with input from the echocardiography laboratory director, should document both the duration of training and the counts of performed and interpreted echocardiograms at the end of their training program (Table 6).

In addition to the training requirements outlined in the foregoing text, proof of competence for individuals trained before 1990 may be established in one of the following three ways: 1) NBE Board Certification; 2) active participation by the physician in a laboratory accredited by the Intersocietal Commission for the Accreditation of Echocardiography Laboratories (ICAEL), with demonstration that the physician interprets a minimum of 300 studies per year, or 3) Endorsement by a Level 3-trained physician who has overread a minimum of 25 examinations interpreted by the individual. This Level 3-trained echocardiography physician may be either on-site or off-site in circumstances where a Level 3-trained physician is not available on-site.

Board Examination. The NBE was formed in December of 1998 to establish criteria for Special Competence in Adult Echocardiography. These requirements include the successful completion of a written board examination for Special Competence in Adult Echocardiography, known as the ASCeXAM, and the completion training requirements consistent with this statement and the COCATS document.

Certification. The NBE has established a process to issuing certification for Special Competence in Adult Echocardiography, specifically in transthoracic two-dimensional and Doppler echocardiography, to physicians who have successfully completed all training requirements and have passed the ASCeXAM. Specific details regarding certification are offered on the NBE web site: www.echoboards.org.

Maintenance of Competence (Table 6). Clinical competence in echocardiography requires continued maintenance of skills in two-dimensional and Doppler echocardiography. Upon completion of the training requirements as previously discussed, a minimum of performance and/or interpretations of 300 examinations per year are required to remain proficient in providing echocardiographic services at Level 2. Because Level 3 skills include the supervision and education of sonographers and physicians training in echocardiography, maintenance of these skills requires physicians to perform and/or interpret a minimum of 500 transthoracic echocardiograms annually. In addition, it is essential that Level 3 physicians maintain their skills by performing transthoracic examinations. This can be done by periodically assisting the sonographers with the performance of more complex cases. Continuing medical education in echocardiography is essential to keep pace with ongoing technical advances, refinements in established techniques, and applications of new methods. Although minimal guidelines for CME are outlined in Section A, it is recommended that Level 3 physicians exceed these minimal standards so that they can remain as true experts in echocardiography. A program for continuous quality improvement in echocardiography should be employed as outlined in the ASE Continuous Quality Improvement document.⁽⁶⁾