c© 2012 Wiley Periodicals, Inc. 1

CASE REPORT

Left Ventricular OutflowTract–Right Atrial FistulaFollowing Aortic ValveReplacement

Elsayed Elmistekawy, M.D.,∗ Sean Dickie,

M.D.,† Donna Nicholson, M.D.,† and

Thierry Mesana, M.D., Ph.D.∗

Departments of ∗Cardiac Surgery;and †Anesthesia, Ottawa Heart Institute,Ottawa, Canada

ABSTRACT A 59-year-old male, undergoing outpa-

tient treatment of a sternal wound infection fol-

lowing elective aortic valve replacement surgery,

presented with decompensated heart failure. The

patient required emergency redo surgery after in-

vestigations revealed a left ventricular outflow

tract to right atrial fistula due to endocarditis with

right ventricular dysfunction. Echocardiography, in

particular transesophageal echocardiography, was

essential for the diagnosis of this rare event. doi:10.1111/j.1540-8191.2012.01486.x (J Card Surg2012;**:1-3)

The occurrence of a left ventricular outflow tract–right atrial (LVOT-RA) fistula is very rare after aorticvalve replacement. It has been associated with traumato the LVOT and excessive debridement during valveimplantation.1–3 We report the case of a 59-year-oldmale who developed an LVOT-RA fistula secondaryto endocarditis following elective aortic valve replace-ment.

CASE REPORT

A 59-year-old male with a medical history of coronarydisease treated with patent stents, severe peripheralvascular disease with previous bilateral femoral-popliteal bypass, hypertension, and type 2 diabetesmellitus presented with severe bicuspid aortic steno-sis. The patient underwent an elective aortic valvereplacement with a mechanical valve with nonpled-geted 2/0 Ethibond sutures (#23 On-X, Medical CarbonResearch Institute, Austin, TX, USA). Transesophagealechocardiogram (TEE) showed a well-seatedvalve and no paravalvular leak or shunts. His initial

Conflict of interest: None to disclose.

Address for correspondence: Thierry Mesana, M.D., Ph.D., F.R.C.S.C.,Professor, University of Ottawa, Chief, Division of Cardiac Surgery,University of Ottawa Heart Institute, Ottawa, Canada. Fax: +1 613761 4712; E-mail: tmesana@ottawaheart.ca

postoperative course was complicated by reexplo-ration for excessive bleeding on the day of surgery.The patient was discharged home on postoperativeday 6 but was readmitted because of a sternal woundinfection which required sternal debridement. Woundand blood cultures showed Staphylococcus aureusand the patient was placed on intravenous Cefazolin(Ancef R©) therapy. The transthoracic echocardiog-raphy performed on readmisison demonstrated awell-seated prosthetic aortic valve with no evidenceof vegetations or fistula, shunts other abnormalities.Unfortunately, the general condition of the patientdeteriorated and he required ICU admission andreintubation for decompensated cardiogenic shock asevidenced by hypotension, oligurea, and an alteredlevel of consciousness. The patient was stabilized withmultiple inotropic medications. Workup for suspectedseptic shock included a TEE which revealed a newfistula between the LVOT and the right atrium withleft-to-right shunt which was not seen on previoustransthoracic echocardiograms. The patient was takenurgently to the operative room for repair of the fistulaas well as rereplacement of the aortic valve. Intraop-eratively, the TEE showed a fistula tract measuring8 mm in diameter with a measured pulmonary tosystemic flow (Qp/Qs) ratio of 3 to 1 (Figure 1).The right ventricle was moderately dilated withmoderate systolic dysfunction on inotropic support.The interatrial septum was intact with no evidencefor an atrial septal defect. There was no obvious rootabscess but there was a distinct area of thickeningnear the noncoronary cusp that was in continuity withthe LVOT-RA fistula.

Because of the wound infection, the sternal reentrywas difficult due to active infection and recently ad-hesions. Transaortic exploration showed no evidenceof vegetations on the prosthetic valve but there wasa mild dehiscence at the commissure between noneand right coronary cusps. Once the valve was ex-tracted, it was easy to identify the fistulous tract belowthe aortic valve into the right atrium. The surround-ing area of the fistula was inflamed and infected. Theexplanted valve and tissues from the fistula edgeswere sent for microbiology. No organisms were cul-tured. Repair was achieved with a pericardial patchand 4/0 prolene stitches. After repair of the fistula, theright atrium was filled with saline and there was noevidence of any residual fistulous communication. Abioprosthetic aortic valve (#23 perimount CE valve, Ed-wards Lifesciences, Irvine, CA, USA) was implanted us-ing 2/0 pledgeted Ethibond stitches. Transesophagealechocardiography showed mild tricuspid regurgitation,no evidence of a residual LVOT-RA fistula, no paravalvu-lar leaks, and good biventricular function on inotropicsupport. There was no evidence of LVOT obstructionwith normal LVOT gradients observed. Blood gas analy-sis from the RA, pulmonary artery (PA) and arterial linesdid not suggest the presence of any significant resid-ual shunt. Closure of the median sternotomy incision

2 ELMISTEKAWY, ET AL.LEFT VENTRICULAR OUTFLOW TRACT-RIGHT ATRIAL FISTULA

J CARD SURG2012;**:1-3

Figure 1. (A) Two-dimensional mid-esophageal view of the left ventricular outflow tract–right atrium fistula at 46◦. Thick arrowpoints to the fistula location (LA = left atrium; LV = left ventricle; MV = mitral valve; RA = right atrium; RV = right ventricle;TV = tricuspid valve); (B) 2D mid-esophageal four-chamber view of the left ventricular outflow tract–right atrium fistula at 0◦.Thick arrow points to the fistula location (LVOT = left ventricular outflow tract); (C) Color Doppler mid-esophageal view of the leftventricular outflow tract–right atrium fistula at 46◦. Thick arrow points to the shunt through the fistula (RA = right atrium; LVOT =left ventricular outflow tract).

J CARD SURG2012;**:1-3

ELMISTEKAWY, ET AL.LEFT VENTRICULAR OUTFLOW TRACT-RIGHT ATRIAL FISTULA

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required further debridement of the sternum and aRobicsek technique closure, the soft tissue and skinwere closed en bloc with interrupted vertical mattressNylon stitches. Postoperative transthoracic echocardig-raphy showed no residual shunt, a well-seated biopros-thetic aortic valve without evidence of vegetations orparavalvular leaks. Postoperatively, the patient devel-oped a superficial wound infection and was ultimat-ley discharged home with intravenous antibiotics. Cur-rently (six months after his second surgery), the patientis in a good general condition with no recurrence ofinfection and a well-healed wound. Patient was con-sented for publication without personal identificationdata or personal images. Approval by the Human Re-search Ethics Board at our institute was obtained topublish this case report.

COMMENT

The congenital left ventricle to RA shunt is a well-described entity; however, acquired LVOT to RA fis-tula is a rare entity after aortic valve surgery.1,3 In hisreview, Jackson et al. found that the incidence is lessthan 0.5% for left-to-right shunt after aortic valve re-placement.4 The etiology of this type of fistula is un-clear but may be due to injury to the membranous sep-tum during dissection below the noncoronary cusps,perivalvular damage attributable to improper retraction,excessive debridement of calcium from the annulus,and/or ischemic necrosis resulting from inclusion of themembranous portion of the ventricular septum in theprosthetic valve suture line.5 Endocarditis is a possiblecause as in the case described earlier. The timing andpresentation is often highly variable, from the immedi-ate postoperative period to months or years after theinitial surgical procedure, and from asymptomatic tohemodynamic instability or shock.1,2,6 The diagnosis

of this fistula may be difficult but echocardiography,more specifically, transesophageal echocardiography,is the definitive method for diagnosis.2,7 Surgical treat-ment is recommended to prevent the developmentof right-sided congestive heart failure. LVOT-RA fis-tula can be closed from the right atrium or throughthe aorta especially if there is a need to deal with theaortic valve. Depending on the size, the fistula can berepaired by primary surgical closure with pledgeted su-tures, or by patch repair using a synthetic patch or apericardial patch. The latter is preferred in endocarditissettings.7

REFERENCES

1. Silverman N, Sethi G, Scott S: Acquired left ventricular-right atrial fistula following aortic valve replacement. AnnThorac Surg 1980;30(5):482-486.

2. Subramaniam K, Wei L: Left ventricular outflow tract toright atrial fistula after aortic valve replacement. J Cardio-thorac Vasc Anesth 2009;23(3):360-363.

3. Sinisalo J, Sreeram N, Jokinen E, et al: Acquired leftventricular—right atrium shunts. Eur J Cardiothorac Surg2011;39(4):500-506.

4. Jackson DH Jr, Murphy GW, Stewart S, et al: Delayedappearance of left-to-right shunt following aortic valvu-lar replacement. Report of two cases. Chest 1979;75(2):184-186.

5. Lorenz J, Reddy CV, Khan R, et al: Aortico-right ven-tricular shunt following aortic valve replacement. Chest1983;83(6):922–925.

6. Hilberath JN, Shook D, Shernan SK, et al: Left ventricularoutflow tract to right atrial fistula diagnosed by intraop-erative transesophageal echocardiography. Anesth Analg2007;104(2):261-262.

7. Al Ahmari S, Malouf J, Al Atawi F, et al: Anatomical ba-sis for acquired intracardiac shunt postaortic valve re-placement: Doppler echocardiographic diagnosis. Eur JEchocardiogr 2004;5:68-71.