Assessment of adult congenital heart disease with multi-detector computed tomography – beyond coronary lumenography

Congenital heart disease in aircrew

This article focuses i on the broad aviation medicine considerations that are required to optimally manage aircrew ii with suspected or confirmed congenital heart disease (both pilots and non-pilot aviation professionals). It presents expert consensus opinion and associated recommendations and is part of a series of expert consensus documents covering all aspects of aviation cardiology. This expert opinion was born out of a 3 year collaborative working group between international military aviation cardiologists and aviation medicine specialists, as part of a North Atlantic Treaty Organization (NATO) led initiative to address the occupational ramifications of cardiovascular disease in aircrew (HFM-251) many of whom also work with and advise civil aviation authorities.

Diagnosis and Management of Patent Ductus Arteriosus

Preterm infants are at increased risk for patent ductus arteriosus (PDA). Prolonged exposure to PDA may be deleterious and has been associated with neonatal morbidity and mortality. Although the molecular mechanisms underlying regulation of postnatal ductus arteriosus closure are not fully understood, clinical experience and research trials have informed recent changes in PDA management strategies and refocused treatment strategies on smaller subsets of infants who require intervention. This review examines current diagnostic and management approaches to PDA in preterm neonates.

Korean guidelines for the appropriate use of cardiac CT

The development of cardiac CT has provided a non-invasive alternative to echocardiography, exercise electrocardiogram, and invasive angiography and cardiac CT continues to develop at an exponential speed even now. The appropriate use of cardiac CT may lead to improvements in the medical performances of physicians and can reduce medical costs which eventually contribute to better public health. However, until now, there has been no guideline regarding the appropriate use of cardiac CT in Korea. We intend to provide guidelines for the appropriate use of cardiac CT in heart diseases based on scientific data. The purpose of this guideline is to assist clinicians and other health professionals in the use of cardiac CT for diagnosis and treatment of heart diseases, especially in patients at high risk or suspected of heart disease.

Assessment of the myocardium with cardiac computed tomography

The imaging of myocardial disease is of increasing importance for cardiologists from all subspecialties, for diagnosis, risk stratification, or to facilitate therapy. While the gold standard modalities for such assessment are cardiac magnetic resonance and echocardiography, these are not universally suitable. Cardiac computed tomography (CT), well-established for the assessment of coronary artery disease (CAD), can be of value in the assessment of myocardial pathology, due to excellent patient compatibility and tolerability, high spatial resolution, and acceptable tissue characterization. This review considers the value and limitations of CT in the assessment of the myocardial sequelae of CAD, and for patients with a variety of other cardiomyopathic diseases, depicts some of the common findings, and considers current developments in this area.

Imaging congenital heart disease in adults

Transthoracic echocardiography is the first-line modality for cardiovascular imaging in adults with congenital heart disease (ACHD). The windows of access that are possible with transthoracic echocardiography are, however, rarely adequate for all regions of interest. The choice of further imaging depends on the clinical questions that remain to be addressed. The strengths of MRI include comprehensive access and coverage, providing imaging of all parts of the right ventricle, the pulmonary arteries, pulmonary veins and aorta. Cine images and velocity maps are acquired in specifically aligned planes, with stacks of cines or dynamic contrast angiography providing more comprehensive coverage. Tissues can be characterised if necessary, and MRI provides relatively accurate measurements of biventricular function and volume flow. These parameters are important in the assessment and follow-up of adults after repairs for tetralogy of Fallot or transposition of the great arteries and after Fontan operations. The superior spatial resolution and rapid acquisition of CT are invaluable in selected situations, including the visualisation of anomalous coronary or aortopulmonary collateral arteries, the assessment of luminal patency after stenting and imaging in patients with pacemakers. Ionising radiation is, however, a concern in younger patients who may need repeated investigation. Adults with relatively complex conditions should ideally be imaged in a specialist ACHD centre, where dedicated echocardiographic and cardiovascular MRI services are a necessary facility. General radiologists should be aware of the nature and pathophysiology of congenital heart disease, and should be alert for previously undiagnosed cases presenting in adulthood, including cases of atrial septal defect, aortic coarctation, patent ductus arteriosus, double-chambered right ventricle and congenitally corrected transposition.

Recommendations for cardiovascular magnetic resonance in adults with congenital heart disease from the respective working groups of the European Society of Cardiology

This paper aims to provide information and explanations regarding the clinically relevant options, strengths, and limitations of cardiovascular magnetic resonance (CMR) in relation to adults with congenital heart disease (CHD). Cardiovascular magnetic resonance can provide assessments of anatomical connections, biventricular function, myocardial viability, measurements of flow, angiography, and more, without ionizing radiation. It should be regarded as a necessary facility in a centre specializing in the care of adults with CHD. Also, those using CMR to investigate acquired heart disease should be able to recognize and evaluate previously unsuspected CHD such as septal defects, anomalously connected pulmonary veins, or double-chambered right ventricle. To realize its full potential and to avoid pitfalls, however, CMR of CHD requires training and experience. Appropriate pathophysiological understanding is needed to evaluate cardiovascular function after surgery for tetralogy of Fallot, transposition of the great arteries, and after Fontan operations. For these and other complex CHD, CMR should be undertaken by specialists committed to long-term collaboration with the clinicians and surgeons managing the patients. We provide a table of CMR acquisition protocols in relation to CHD categories as a guide towards appropriate use of this uniquely versatile imaging modality.

X-ray computed tomography of the heart

INTRODUCTION

Cardiac imaging is an emerging application of multidetector computed tomography (MDCT). This review summarizes the current capabilities, possible applications, limitations and developments of cardiac CT.

SOURCES OF DATA

Relevant publications in peer reviewed literature and national and international guidelines are used to discuss important issues in cardiac CT imaging.

AREAS OF AGREEMENT AND CONTROVERSY

There is broad consensus that coronary CT angiography is indicated in patients with an intermediate pre-test probability of coronary artery disease (CAD) when other non-invasive tests have been equivocal. In this context, CT can reliably exclude significant CAD. Cardiac CT also has an established role in the evaluation of bypass grafts and suspected coronary anomalies. Radiation exposure from CT procedures remains a concern, although techniques are now available to reduce the X-ray dosage without significantly compromising the image quality. However, with the current level of knowledge, the cardiac CT examinations are not justified to screen for CAD in asymptomatic individuals. Neither is it considered appropriate in patients with a high pre-test probability of CAD, for whom invasive catheter coronary angiography is usually of more benefit.

GROWING POINTS AND AREAS TIMELY FOR DEVELOPING RESEARCH

The ability to reconstruct the volumetric cardiac CT data set opens up avenues for advanced physiological analyses of the heart. For example, if CT myocardial perfusion assessment becomes a reality, there is potential to revolutionize the practice of MDCT imaging. Research is also ongoing to investigate whether cardiac CT has a role in the appropriate triage of patients with chest pain in the emergency department.

MDCT features of cardiothoracic sources of stroke

Multidetector computed tomography (MDCT) is widely used in the assessment of cardiothoracic disease and provides high-resolution images of the heart, great vessels, and lungs. A range of cardiothoracic conditions can precipitate stroke, including intracardiac thrombus, right-to-left shunts, and diseases of the thoracic aorta. Many of these conditions may be identified on non-electrocardiogram (ECG)-gated studies, but the advent of high temporal resolution ECG-gated MDCT provides superior anatomical delineation. Radiologists should be familiar with the pathogenesis and CT features of cardiothoracic conditions that can precipitate stroke as their early identification to enables appropriate management and prognostic decisions.

Cardiac multi-detector CT: its unique contribution to cardiology practice

Medical practice is moving fast towards non-invasive and non-surgical disease management. While significant progress has been made with coronary artery disease prevention, MDCT stands as an ideal non-invasive tool for its progression. It accurately assesses both arterial lumen and wall disease. Although the main concern of current cardiology practice is the coronary stenotic disease, arterial wall calcification itself may significantly contribute to patients' symptoms. Thus, in addition to the beneficial use of MDCT in patients with mild to moderate risk for coronary disease, the unique information it provides on wall disease may assist the management of symptomatic patients with no flow-limiting lesions.

Multidetector computed tomography in the adolescent and young adult with congenital heart disease

As a result of improved postoperative management and transcatheter interventions, the number of adults with congenital heart disease in the United States has grown exponentially. Consequently, noninvasive imaging has taken an essential role in the evaluation of this patient population. Although standard noninvasive imaging tools such as transthoracic echocardiography and cardiovascular magnetic resonance may be invaluable to this group, occasionally there may be contraindications to their use or limitations in their utility. Multidetector computed tomography (MDCT) has only recently been used in the assessment of the adult with congenital heart disease. The ever-increasing availability of MDCT, along with its increased spatial and temporal resolution and rapidity of postprocessing, makes this an attractive first-choice to study this complex group. A successful scan requires familiarity with the complexity of the underlying anatomy and prior palliative or complete surgical repairs. It is with this knowledge in mind that MDCT provides exquisite detail of complex, 3-dimensional anatomic relations. This review illustrates the spectrum of MDCT findings in the adult with simple and complex forms of congenital heart disease.