With the advantages of echocardiography, magnetic resonance imaging (MRI), computed tomography (CT), and single-photon emission tomography as primary analytical and treatment planning tools for cardiovascular disease, the chest radiograph has less importance for primary cardiac assessment than it did in the past. Nevertheless, the ubiquity of chest radiography in medical care presents many opportunities for recognition of intrathoracic manifestations of cardiovascular pathology and pathophysiology that could then lead to definitive diagnosis with one of the aforementioned advanced imaging techniques. Moreover, within the acute care setting, chest radiography is a critical tool for assessing the position of supportive devices and for detecting life-threatening complications of such devices (eg, hemorrhage and pneumothorax).
Despite its loss of primacy for the assessment of many primary cardiac disorders,1,2,3,4 a systematic search of the radiograph performed independent of the results of other imaging tests allows for recognition of such complications. Although some experts recommend performing the initial interpretation without clinical information to prevent erroneous information from misleading the radiographic interpretation, there are no published data to support this approach. Moreover, the development of the electronic health record and its associated widespread availability at the time of radiographic interpretation provides a basis for substantially greater value of an interpretation made within the context of prior information and leading to clinically actionable analyses. Nevertheless, bearing in mind the principle of blinded radiographic interpretation will prepare the interpreter to identify unexpected findings that might have been missed in a search directed by symptoms and medical history. Even when the interpreter prefers a blinded initial interpretation. the final radiographic diagnosis should be made only after correlating the radiographic findings with clinical information and other laboratory data.5
The radiographic examination for heart disease consists of four major steps. They are (1) radiographic examination for anatomy, (2) comparison to prior studies, (3) clinical correlation, and (4) conclusion and recommendations.
VISUAL SEARCH AND CHARACTERIZATION OF ABNORMALITIES
A detailed explanation of chest radiographic search and interpretation is beyond the scope of this chapter. As was mentioned, a search pattern that involves comprehensive evaluation of all thoracic structures is key to ensuring a thorough analysis. There is no one correct approach to the patterned search, but each search and assessment should include a dedicated assessment of all visible structures.
In the setting of cardiac disease, it is tempting to principally focus on the heart, but cardiac conditions can be manifest in noncardiac structures. For instance, a right-sided stomach with an absent inferior vena cava (IVC) margin suggests congenital interruption of the IVC with azygos continuation6,7 (Fig. 14–1). A narrowed anteroposterior (AP) diameter of the thorax can be the cause of an innocent murmur8 (Fig. 14–2).
Patient with situs ambiguus, interruption of the inferior vena cava ...