doi: 10.1161/CIRCIMAGING.108.790931
Cardiovascular Images |
An Unusual Cause of Aortic Regurgitation
From the Department of Cardiology, Methodist DeBakey Heart and Vascular Center, The Methodist Hospital, Houston, Tex.
Correspondence to Sherif F. Nagueh, MD, Methodist DeBakey Heart Center, 6550 Fannin, SM-677, Houston, TX 77030. E-mail snagueh{at}tmhs.org
A 42-year-old man presented with acute onset of severe dyspnea, fever, and positive blood cultures for Staphylococcus aureus. His medical history was relevant for aortic root surgery, including replacement of the aortic root and aortic valve with a homograft 3 years ago. His physical examination revealed sinus tachycardia, a heart rate of 120 bpm, and a blood pressure of 84/45 mm Hg. Bibasilar rales were present, and the jugular veins were distended to the angle of the mandible. Transesophageal echocardiography was performed to examine the underlying reasons for his acute deterioration.
Transesophageal echocardiography revealed the presence of a dehiscence of the homograft, with flow occurring between the left ventricular outflow tract and a pseudoaneurysm in the plane of the intervalvular fibrosa, without vegetations on the aortic valve. Hemodynamically significant aortic regurgitation (AR) was present through the site of the dehiscence, but not the aortic valve itself (Data Supplement Movies I-IV), and pulsed wave Doppler of the descending aorta revealed holodiastolic flow reversal (Figure 1). Continuous wave Doppler signal of the AR jet was consistent with significant AR, showing a short pressure half-time (Figure 2). In addition, echolucent areas with septations were seen surrounding the homograft (Data Supplement Movie I), consistent with multiple abscess cavities. Doppler interrogation showed early closure of the mitral valve and diastolic mitral regurgitation (Figure 3, left). Pulmonary venous flow (Figure 3, right) revealed a reduced systolic velocity to diastolic velocity ratio and a prominent atrial reversal signal. Collectively, these Doppler findings are consistent with a highly elevated left ventricular end-diastolic pressure (atrial reversal >50 cm/s, premature closure of the mitral valve, and diastolic mitral regurgitation), as well as an increased mean left atrial pressure (systolic/diastolic, <1) due to AR.
|
|
|
Aortic graft dehiscence is a rare complication after aortic root surgery, whether with composite grafts or homografts. The hemodynamic consequences depend on the extent of dehiscence and can lead to severe perivalvular regurgitation and acute heart failure, as in this case. Aortography may not visualize a single site dehiscence, nor the mechanism of regurgitation. On the other hand, transesophageal echocardiography has a high accuracy in identifying the location and extent of the dehiscence, the presence of aortic root and aortic valve pathology, and the severity of regurgitation, as seen in this case.
 |
Acknowledgments |
|---|
Disclosures
None.
|
Footnotes |
|---|
The online-only Data Supplement is available at http://circimaging.ahajournals.org/cgi/content/full/1/2/e13/DC1
| ||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||