European Journal of Echocardiography 2008 9(1):88-91; doi:10.1016/j.euje.2007.02.010
Published on behalf of the European Society of Cardiology. All rights reserved. © The Author 2007. For permissions please email: journals.permissions@oxfordjournals.org.
Extensive dehiscence of a stentless bioprosthesis with only mild paravalvular regurgitation after replacement of a degenerated bicuspid aortic valve
Dirk Poppe*,
Peter Blank,
Uta Böge,
Tatjana Kölzow,
Jürgen Loh and
Bernhard Schwaab
Curschmann-Klinik, Timmendorfer Strand, Germany
Received 2 February 2007; accepted after revision 14 February 2007; online publish-ahead-of-print 2 April 2007.
* Corresponding author. Curschmann-Klinik der Klinikgruppe Dr. Guth, Saunaring 6, D-23669 Timmendorfer Strand, Germany. Tel: +49 (0)4503 602 154; fax: +49 (0)4503 602 660. E-mail address: dr.poppe{at}drguth.de
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Abstract
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We report the case of a 54-year-old patient admitted for rehabilitation
after implantation of a stentless bioprosthesis due to severe
insufficiency of a degenerated bicuspid aortic valve. The patient
could fully participate in a standard cardiac rehabilitation
program without any signs of haemodynamic instability. Transthoracic
echocardiography showed a small mobile subvalvular structure
and only mild paravalvular reflux. Transesophageal echocardiography,
however, revealed extensive dehiscence of the bioprosthesis
with the need for urgent reoperation. We discuss the probable
causes and encourage routine echocardiography after valve operations
with generous application of transesophageal echocardiography
in every suspicious case.
Keywords: Echocardiography; Transesophageal; Stentless; Valve; Surgery; Complication
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Case report
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In June, 2005, a 54-year-old male patient was admitted to our
rehabilitation hospital 11 days after implantation of a stentless
bioprosthesis (diameter 29 mm, Pericarbon
TM Freedom, Sorin Biomedica
Cardio S. p. A., Saluggia, Italy) in aortic position due to
severe insufficiency of a degenerated bicuspid aortic valve
(BAV). In the operation report the use of continuous sutures
for both the anulus and the commissures was described. Apart
from a short episode of atrial fibrillation which was converted
by amiodarone and electric cardioversion, the further postoperative
course had been eventless.
On admission, the patient reported only slight postoperative chest pain and denied any palpitation, dyspnea, leg swelling, vertigo or syncope. Physical examination revealed normal body temperature, a regular heart rate of 78/min, a blood pressure of 120/70 mmHg and no signs of cardiorespiratory insufficiency. Auscultation revealed normal heart sounds with no systolic or diastolic murmurs. The lungs were clear with no rales or wheezing.
The electrocardiogram showed normal sinus rhythm with complete left bundle branch block. Laboratory tests revealed light postoperative anemia without elevated inflammatory parameters or lactate-dehydrogenase. Chest X-ray showed only a small left-sided pleural effusion.
On day one after admission to our institution, a standard 2-dimensional transthoracic echocardiography (TTE) was performed (Vivid 3 Expert, GE Healthcare Technologies, Waukesha, Wisconsin, USA) showing left ventricular (LV) hypertrophy (14–15 mm) and enlargement (enddiastolic/endsystolic diameters 66/48 mm, enddiastolic/endsystolic volume 245/130 ccm, respectively). LV ejection fraction was reduced to 45–50% (biplane Simpson's method) due to general hypokinesia and paradoxical septal movement. A circumferential pericardial effusion of less than 5 mm was present without compression of the right atrium or ventricle. In the TTE, morphology of the aortic bioprosthesis was normal. Below the valve, however, an echodense structure of 16 mm in length raised from the wall of the left ventricular outflow tract (LVOT) in systole and seemed to be attached to the anulus of the aortic valve prosthesis on the side of the right coronary cusp (RCC) (Figure 1). Color Doppler showed a mild paravalvular regurgitation in this area (Figure 2).
In repeated TTE investigations, morphology of the aortic valve
prosthesis, the subvalvular structure and the small paravalvular
regurgitation remained unchanged; the pericardial effusion had
disappeared. The patient, staying in stable physical condition
with no signs of cardiorespiratory insufficiency, could fully
participate in the routine rehabilitation program (maximum work
load of 75 Watts during bicycle-ergometry, continuous bicycle
training at 50 Watts over 20 min, participation in walking and
gymnastics groups). Repeated laboratory tests showed no elevation
of inflammatory parameters or lactate-dehydrogenase.
On day 14 after admission, a transesophageal echocardiography (TEE) was performed to identify the subvalvular structure and further clarify the mechanism of the paravalvular leakage. The most significant findings are shown in Figures 3–5: The bioprosthesis itself showed no signs of deterioration, the cusps were tender and showed normal mobility without any transvalvular regurgitation. The short axis view (40–50° rotation), however, showed an almost circular dehiscence between the anulus of the valve and the aortic wall with tight contact only at the commissures between the non-coronary cusp (NCC) and the left coronary cusp (LCC) as well as between NCC and RCC (Figure 3). In systole, the anulus bulged inwards on the level of the commissure between RCC/LCC giving space to a significant paravalvular systolic outflow in this area. In diastole, this part of the anulus moved back into close contact with the aortic wall thus allowing only little diastolic regurgitation (Figure 4). In the longitudinal axis (134° rotation) the subvalvular structure, undefined in TTE, could be identified as part of the aortic wall attached to the anulus of the valve (Figure 5) suggesting a circumscript dissection of the aortic wall in this area. Also in longitudinal axis, an echo-free space was detected between the tubular part of the prosthesis and the aortic wall, while the top of the prosthesis seemed to be closely fixed to the aortic wall (Figure 5). Figure 6 shows color Doppler imaging in longitudinal axis.
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Figure 3 Transesophageal echocardiography (TEE), short axis view (50°) in midesophageal level. Left: Extensive dehiscence between the anulus of the bioprosthesis and the aortic wall during systole, with tight contact only at the commissures between NCC and LCC (NL) as well as between NCC and RCC (NR). Right: In diastole, the anulus moves back into close contact with the aortic wall.
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Figure 4 TEE, short axis view (46°) in midesophageal level, color Doppler imaging. Left: In systole, flow can be seen through the center of the valve as well as through the space between anulus and aortic wall in the area of the commissure between LCC and RCC (arrow). Right: In diastole, only mild regurgitation is visible.
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Figure 5 TEE, long axis view (134°) in midesophageal level. Left: In systole, the subvalvular mobile structure (MS) and parts of the anulus of the bioprothesis raise from the aortic wall. Also, an echofree space (SP) is visible between the tubular part of the bioprosthesis and the aortic wall. Right: In diastole, these structures move back into close contact to the aortic wall.
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Figure 6 TEE, long axis view (134°) in midesophageal level, color Doppler imaging. Same view as in Figure 5, showing significant paravalvular forward flow during systole (left) with only mild regurgitation during diastole (right) (arrows).
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On the basis of these TEE findings, significant dissolution
or rupture of sutures for most parts of the proximal anulus,
the commissure between RCC and LCC and probably part of the
other commisures was diagnosed. Even though urgent reoperation
was recommended, the patient hesitated and surgery was not performed
until 2 months after the primary operation.
At time of reoperation the intraoperative inspection of the stentless bioprosthesis revealed intact sutures only in the area of the NCC/LCC commissure and the distal end of the tubular part of the prosthesis. The structurally intact bioprosthesis was removed in total, several lacerations on the inside of the ascending aorta were repaired and finally a mechanical valve was implanted. 14 months later, the patient has fully recovered and is in a good state of health.
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Discussion
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Stentless aortic bioprostheses are increasingly implanted due
to better hemodynamic performance and patient survival
1,2. Implantation
procedure, however, is technically more demanding given the
necessity of sewing not only the anulus but also the commissures
and the distal end of the prosthesis to the aortic wall rigorously
avoiding any geometric distortion
3–5. Several techniques
exist using interrupted or continuous sutures or a combination
of both.
In our case, continuous sutures were used which may have contributed to the extensive dehiscence of the valve, as disruption of a continuous suture leads to larger areas of dehiscence than disruption of a single or several interrupted sutures.
The multiple lacerations of the aortic wall seen during reoperation lead attention to the underlying valvular disease. A degenerated bicuspid aortic valve (BAV) may be associated with several concomitant conditions, such as a persistent ductus arteriosus Botalli or aortic coarctation.6 In addition, characteristic histologic changes of the aortic wall could be found in patients with a BAV7–9that explain the association between this particular valve disease and ectasia or aneurysms of the ascending aorta as well as aortic dissections.10,11Although the patient presented exhibited no dilatation of the ascending aorta, a possible higher vulnerability of the aortic wall may have contributed to the lacerations seen. As no specimen of the aortic wall was saved during either operation, further histologic investigation was not performed.
Usually the amount of regurgitation as detected by transthoracic echocardiography is presumed to correspond to the morphological size of the paravalvular leakage. In the case presented, however, there was only a mild regurgitation, due to the close contact between the anulus of the aortic valve and the aortic wall during diastole. In addition, there were no clinical or laboratory signs of relevant aortic insufficiency and transthoracic echocardiography was not able to detect the true pathology. Only transesophageal echocardiography revealed the impending danger of complete disruption and dislocation of the aortic valve bioprosthesis which might have later resulted in a critical hemodynamic situation with possible lethal consequences.
In conclusion, transthoracic echocardiography (TTE) should be used rigorously and routinely in every patient early after valve surgery. Transesophageal echocardiography should generously be used in cases of impaired transthoracic viewing conditions and in every case of suspicious findings in TTE, even in the absence of clinical signs of valve dysfunction.
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References
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- Westaby S, Horton M, Jin XY, Katsumata T, Ahmed O, Saito S, et al. Survival advantage of stentless aortic bioprostheses. Ann Thorac Surg (2000) 70:785–90.[Abstract/Free Full Text]
- Akar AR, Szafranek A, Alexiou C, Janas R, Jasinski MJ, Swanevelder J, et al. Use of stentless xenografts in the aortic position: determinants of early and late outcome. Ann Thorac Surg (2002) 74:1450–7.[Abstract/Free Full Text]
- Ennker J, Florath I, Rosendahl U, Bauer S, von Hodenberg E, Ennker IC. Risk of perioperative mortality and complications following biological aortic valve replacement in elderly patients: stented vs. unstented prostheses. Z Kardiol (2001) 90(Suppl 6):58–64.[CrossRef][Web of Science][Medline]
- Beholz S, Hunter S, Alcon CA, Zussa C. Recommendations for the implantation of the pericarbon freedom stentless valve. Heart Surg Forum (2005) 8:E409–11.[CrossRef][Web of Science][Medline]
- Van Nooten G, Caes F, Francois K, Van Belleghem Y, Taeymans Y. Stentless or stented aortic valve implants in elderly patients? Eur J Cardiothorac Surg (1999) 15:31–6.[Abstract/Free Full Text]
- Ward C. Clinical significance of the bicuspid aortic valve. Heart (2000) 83:81–5.[Free Full Text]
- Bauer M, Pasic M, Meyer R, Goetze N, Bauer U, Siniawski H, et al. Morphometric analysis of aortic media in patients with bicuspid and tricuspid aortic valve. Ann Thorac Surg (2002) 74:58–62.[Abstract/Free Full Text]
- Bonderman D, Gharehbaghi-Schnell E, Wolleneck G, Maurer G, Baumgartner H, Lang IM. Mechanisms underlying aortic dilatation in congenital aortic valve malformation. Circulation (1999) 99:2138–43.[Abstract/Free Full Text]
- De Sa M, Moshkovitz Y, Butany J, David TE. Histologic abnormalities of the ascending aorta and pulmonary trunk in patients with bicuspid aortic valve disease: clinical relevance to the Ross procedure. J Thorac Cardiovasc Surg (1999) 118:588–94.[Abstract/Free Full Text]
- Nkomo VT, Enriquez-Sarano M, Ammash NM, Melton LJ 3rd, Bailey KR, Desjardins V, et al. Bicuspid aortic valve associated with aortic dilatation: a community-based study. Arterioscler Thromb Vasc Biol (2003) 23:351–6.[Abstract/Free Full Text]
- Yasuda H, Nakatani S, Stugaard M, Tsujita-Kuroda Y, Bando K, Kobayashi J, et al. Failure to prevent progressive dilation of ascending aorta by aortic valve replacement in patients with bicuspid aortic valve: comparison with tricuspid aortic valve. Circulation (2003) 108(Suppl 1):II291–4.[Medline]
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