Echokardiographische Diagnostik angeborener Herzfehler im Erwachsenenalter

Zusammenfassung

Echo- und dopplerechokardiographische Verfahren haben in der modernen Diagnostik kongenitaler Erkrankungen im Erwachsenenalter einen unverzichtbaren Stellenwert gewonnen. Diese Verfahren erlauben eine detaillierte Erfassung der Pathomorphologie des Herzens ebenso wie eine zuverlässige Beurteilung der hämodynamischen Veränderungen. Dabei ergeben sich für die verschiedenen Verfahren, wie die transthorakale und transösophageale Echokardiographie, die Doppler- und Farbdopplerechokardiographie, die Kontrastechokardiographie sowie die dreidimensionale Echokardiographie differenzierte Indikationsstellungen.

Bei einfachen Fehlbildungen, wie kongenitalen Herzklappenerkrankungen, Erkrankungen des linksventrikulären Ausflußtraktes oder der aszendierenden Aorta, kann die Diagnose vielfach bereits mittels der transthorakalen Echo-und Dopplerechokardiographie gestellt werden. Jedoch sind gerade im Erwachsenenalter die Schallbedingungen häufig limitiert, um detailliert auch kleinere Veränderungen zu erkennen, so daß bei diesen Patienten zur endgültigen Sicherung der Diagnose häufig eine transösophageale Untersuchung erforderlich ist. Auch bei Erkrankungen der thorakalen deszendierenden Aorta, wie zum Beispiel bei Aortenisthmusstenose, ist die transösophageale der transthorakalen Echokardiographie deutlich überlegen.

In der Diagnostik von Shuntvitien haben die Farbdoppler-und die Kontrastechokardiographie eine besondere Bedeutung gewonnen. Vielfach ist auch bei diesen kongenitalen Erkrankungen eine transösophageale Untersuchung indiziert. Das vollständige Verständnis komplexer kongenitaler Fehlbildungen erfordert in der Regel die Durchführung aller echokardiographischen Verfahren. Erste Untersuchungen mittels der dreidimensionalen Echokardiographie sind dabei besonders im Hinblick auf die exakte räumliche Darstellung pathoanatomischer Strukturen sehr vielversprechend.

Abstract

Echo and Doppler echocardiographic procedures have gained special importance in the diagnostics of congenital diseases in adults. These procedures permit detailed visualization of the pathomorphology of the heart as well as reliable evaluation of the hemodynamic changes. There are differentiated indications for the various procedures, such as transthoracic and transesophageal echocardiography, Doppler and color-Doppler echocardiography, contrast echocardiography and 3-dimensional echocardiography. This article discusses the opposition of the various echo and Doppler echocardiographic procedures with respect to the diagnostics of the most frequent non-operated congenital diseases in adults. The pathomorphology of the various congenital diseases will be summarized and then the important echocardiographic criteria presented which are decisive for the diagnostic procedure.

In simple congenital malformation of cardiac valves, such as bicuspid aortic valve (Figure 1: aortic ring abscess), pulmonary valve stenosis (Figure 2), Ebstein’s anomaly (Figure 3) or malformations of the mitral valve (Figure 4: cleft in the anterior mitral cusp), the diagnosis can often be made using transthoracic echo and Doppler echocardiography, and the severity of the defect determined. However, the sonographic conditions, especially in adults, are frequently too limited to permit recognition of detailed smaller changes, so that transesophageal examination is required to finally confirm the diagnosis in these patients.

In the diagnostics of diseases of the left ventricular outflow tract and the thoracic aorta, such as subvalvular aortic valve stenosis (Figure 5), the sinus of Valsalva aneurysm or the coarctation of the aorta (Figure 6), the left ventricular outflow tract can be evaluated morphologically from a transthoracic procedure and the accelerations of flow can be recorded by continuous wave Doppler. If there is no sclerosis of the fibrous membrane, these can often not be depicted by transthoracic procedures, so that a supplementary transesophageal examination is meaningful. This is required in any case for diseases of the descending thoracic aorta.

In the case of congenital lesions, such as atrial septal defects (Figure 7: anomalous pulmonary venous return, Figure 8: 3-dimensional visualization of an atrial septal defect, Figure 9: sinus venosus defect), ventricular septal defect or a patent ductus arteriosus Botalli (Figure 10), color-Doppler and contrast echocardiography have become especially important. Transesophageal examination is also indicated for these congenital diseases for direct depiction of the defect as well as for precise evaluation of the shunt. Moreover, in atrial septal defects, it has been shown that a 3-dimensional echocardiography provides additional advantage with respect to spatial relationship of the defect to the other cardiac structures, as well as presenting dynamic changes during a heart cycle.

Extensive knowledge of complex congenital heart disease, such as tetralogy of Fallot (Figure 11), complete transposition of the great arteries, congenitally corrected transposition of the great arteries (Figure 12), the double-outlet right ventricle, truncus arteriosus communis, the cor triatriatum, tricuspid atresia (Figure 13) or the univentricular heart (Figure 14) usually requires performance of a transthoracic echo- and Doppler echocardiographic examination to assess the pathomorphological changes and to examine hemodynamics. In the majority of patients, supplementary transesophageal echocardiography and an echo contrast examination are important. Initial examinations using 3-dimensional echocardiography are very promising in this connection and with respect to the exact spatial presentation of pathoanatomical structures.