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 Echocardiography

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

Developed in Collaboration with the American Society of Echocardiography, the Society of Cardiovascular Anesthesiologists, and the Society of Pediatric Echocardiography

VII. Echocardiography for CHD Patients

Overview and Indications for the Procedure. Echocardiography is an important resource used in the evaluation of infants, children, and adults with suspected or documented CHD. It has been widely applied for the last several decades and has become a mainstay in daily clinical use. As applied to infants, children, and adults with CHD, echocardiography is comprised of all of the previously described modalities. When combined, they provide a comprehensive anatomic diagnosis along with the assessment of associated flow disturbances. Such information is obtained noninvasively, without patient risk or discomfort. The high accuracy of the information is often sufficient to preclude the need for further invasive diagnostic studies such as cardiac catheterization. Numerous echocardiographic methods have been developed with high sensitivity and specificity for individualized diagnosis and assessment of disease severity. In addition to the method's high accuracy, it has prime utility in serial evaluation of patients for surveillance of the severity and progression of the disease, and the response to therapy.

Echocardiography is indicated in the evaluation of the cardiac anatomy and physiology of infants and children in whom cardiac concerns are present, and in adults with known or suspected CHD. This includes patients in whom cardiac malformations are suspected because a heart murmur has been detected or because of concerns about cyanosis, or congestive failure, or abnormal findings on chest X-ray or ECG. The frequency of repeat echocardiographic examination depends on the severity of the disease, the type of intervention performed, and the age of the patient. Whether it is performed in infants, children, or adults, echocardiography of patients with CHD requires a special knowledge base that is usually acquired during a fellowship in pediatric cardiology. In most cases, a properly trained adult cardiologist with Level 2 or 3 competence in echocardiography should be capable of recognizing simple congenital heart defects (Table 3) and treating affected patients appropriately. However, the same does not apply to complex lesions. Few adult cardiology training programs have a sufficient caseload and case mix of complex lesions to ensure an adequate level of training. Although adult cardiologist echocardiographers may often recognize the presence of a complex CHD, the comprehensive evaluation and management of these lesions require special skills not usually acquired during a conventional adult cardiology fellowship. With the growing number of adults with complex CHD, there is an acknowledged need for cardiologists trained specifically in the care of these patients ⁽¹⁵⁾. Practitioners in adult CHD require special expertise in echocardiography similar to that possessed by pediatric echocardiographers. This section describes the skills required for performing echocardiography in pediatric patients and in adults with complex CHD, along with the training requirements and criteria for proof of competence and maintenance of competence in this area. The definition of "complex CHD" is any congenital lesion other than those mentioned in Table 3.

Minimum Knowledge Required for Performance and Interpretation (Table 17). Competence in performing and/or interpreting echocardiograms in pediatric patients and in adults with complex CHD 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. In addition, a pediatric echocardiographer must be skilled in observing and understanding the behavioral and developmental aspects of infants and children of all ages, in order to alleviate patient fear, establish patient confidence, and be persuasive enough to allow the proper completion of a cardiac ultrasound examination. At times, echocardiographers may be required to administer sedation to obtain adequate examinations, and knowledge of these agents is necessary. These skills are specific to those practitioners performing examinations in children and do not apply to individuals performing examinations only in adults with CHD.

Technical Aspects of the Examination. An echocardiographer must be personally skilled in all aspects of the technical performance and recording of the examination. This includes a review of the indications and goals of the study and the formulation of a plan to accomplish those goals. One must know how to use ultrasound probes of different frequencies to obtain the most comprehensive information possible in a given patient, particularly infants and premature babies. An echocardiographer must be able to scan from all available echo windows and integrate the information from each view. In addition, he/she must be familiar with the use of ultrasound contrast agents, which can enhance the detection of intracardiac shunts. These skills are required even when a physician has access to a sonographer for performance of the examination. Supervising physicians cannot supervise adequately unless they themselves, are capable of performing echocardiograms on infants and children.

Anatomy and Physiology. An echocardiographer examining a patient with complex CHD must be skilled in recognizing anatomic features that identify and characterize specific cardiac structures and allow for diagnosis of specific cardiac malformations. Echocardiographers must be able to identify the abdominal and thoracic situs and perform an anatomic assessment in a segmental anatomic sequence that identifies not only anatomy but also connections. He or she must be fully familiar with associated disease processes and their effect on anatomic findings.

The physiology of many congenital lesions and combinations of lesions is interrelated. The echocardiographer must be familiar with the influence of age, patient size, and hemodynamic state in each lesion, and they must understand the transitional physiology of the neonate, shunt physiology, and the concepts and manifestations of pulmonary hypertension throughout the full pediatric and adultage spectrum. The echocardiographer must be familiar with established techniques used to quantify cardiac function and evaluate different physiologic states and must know how to evaluate the consistency (or lack thereof) of results obtained with these techniques in a given patient.

Recognition of Simple and Complex Pathology. An echocardiographer must have sufficient knowledge and experience to be aware of defects or problems that may cluster together. He/she must be aware of cardiac defects associated with various syndromes and be able to recognize the dysmorphic features of those syndromes.

An echocardiographer must know how to evaluate the several anatomic and physiologic abnormalities that coexist in patients with complex malformations and recognize the effects of altered physiology. They will commonly encounter patients who have undergone surgical intervention for a variety of cardiac problems and for each, they must be aware of the type of surgical procedure and its specific echocardiographic findings. For some lesions, surgical techniques have evolved over the years, so echocardiographers must be aware not only of contemporary surgical approaches but also procedures performed differently in the past. For many of these surgical evaluations, a substantial modification of examination techniques may be required. Interventional procedures for palliation of CHD have become increasingly common. The echocardiographer must have knowledge of the residua and sequelae of these surgical and non-surgical procedures.

Training Requirements (Tables 18 and 19). Training in pediatric echocardiography today involves exposure to echocardiographic principles and techniques during a pediatric cardiology fellowship. One may elect to spend additional time in echocardiography, depending on the fellowship program. Close supervision and guidance by experienced pediatric echocardiographers is essential for proper education, training, and development of technical experience. Training involves not only observation, but also actual hands-on performance of the examination.

Echocardiographic training for cardiologists specializing in adult CHD varies according to the level of training. We recognize that minimum numbers are difficult to define and standardize. However, we endorse the recommendations of the 32nd Bethesda Conference that only cardiologists with Level 2 or 3 training should care for such patients independently ⁽⁵⁾. Training in complex adult congenital disease requires a minimum of 150 complete TTE and 25 TEE (10 intraoperative) studies performed and interpreted in patients with CHD, as well as participation in the interpretation of at least 300 TTE and 50 TEE studies (20 intraoperative) ⁽¹⁶⁾. Case mix is an important aspect of the training experience, and when adequate diversity is not available among adult patients, training should include echocardiographic examinations in children.

Proof of Competence (Table 20). Letter or certificate from training supervisor, or other means of documentation (i.e., log) of fulfillment of the training requirements as outlined above. No test is presently available for evaluating competence in pediatric echocardiography or in assessing complex CHD in adults.

Maintenance of Competence (Table 20). Maintenance of competence in pediatric echocardiography requires a minimum of 400 studies annually for Level 2 practitioners and 800 studies annually for Level 3, with at least 25% of the studies performed in patients under a month of age. For cardiologists caring for patients with adult CHD, the number of examinations performed annually to maintain competence has not been defined. Our recommendation is a minimum of 100, as long as an adequate case mix is assured.