Anesth Analg 2004;99:38-40
© 2004 International Anesthesia Research Society
doi: 10.1213/01.ANE.0000117281.95170.24
CARDIOVASCULAR ANESTHESIA
An Unusual Cause of Left Ventricular Outflow Tract Obstruction After Mitral Valve Repair
Kathryn E. Glas, MD*,
Jack S. Shanewise, MD*, and
Robert A. Guyton, MD
Departments of *Anesthesiology and
Cardiothoracic Surgery, Emory University School of Medicine, Atlanta, Georgia
Address correspondence and reprint requests to Kathryn E. Glas, MD, Department of Anesthesiology, 550 Peachtree St., Atlanta, GA 30308. Address e-mail to kathryn_glas{at}emoryhealthcare.org
 |
Abstract
|
|---|
Left ventricular outflow tract (LVOT) obstruction caused by systolic anterior motion is a cause of failed mitral valve repair. Intraoperative transesophageal echocardiography has been very helpful in diagnosing problems with mitral valve repairs intraoperatively, allowing immediate correction. We report an unusual cause of LVOT obstruction attributed to prolapse of the annuloplasty ring into the LVOT. Intraoperative hemodynamics were normal, and the diagnosis would not have been made before leaving the operative suite without the transesophageal echocardiography.
IMPLICATIONS: The authors describe the intraoperative diagnosis of an unusual cause of left ventricular outflow obstruction in a patient with normal hemodynamic status after mitral valve repair.
|
Introduction
|
|---|
The benefits of operative transesophageal echocardiography (TEE) for mitral valve surgery are well known (1–6). Lack of availability of TEE has been suggested as a risk factor for reoperation (7). In the case of mitral valve repair, operative TEE allows confirmation of reduction in mitral regurgitation (MR), evaluation for presence of systolic anterior motion (SAM), and gradients across the mitral valve or left ventricular (LV) outflow tract (LVOT). We report an unusual cause of LVOT obstruction diagnosed by intraoperative TEE after repair of an ostium primum atrial septal defect (ASD) and cleft anterior mitral leaflet.
|
Case Report
|
|---|
A 49-yr-old woman presented for repair of an ostium primum ASD and repair of a cleft anterior mitral valve leaflet. She presented for treatment when her exercise tolerance decreased from 5-mile-per-day run to 1 mile per day with chest discomfort. She was taking no medications.
She had preoperative placement of a radial artery catheter, and a right internal jugular vein sheath introducer, into which a pulmonary artery (PA) catheter was inserted to 20 cm. The plan was to advance the catheter into the PA after ASD closure. Anesthetic induction and management before cardiopulmonary bypass (CPB) were uneventful. Baseline TEE examination confirmed the diagnosis of an ostium primum ASD with left-to-right interatrial shunting and a cleft in the anterior mitral valve leaflet associated with severe MR (Fig. 1). Biatrial and biventricular enlargement were noted, with an ejection fraction of 55%. The cleft of the anterior leaflet was closed with interrupted sutures. A #30 Carpentier-Edwards Classic annuloplasty ring (Edwards Lifesciences, Irvine, CA) was inserted to remove tension from the sutures in the cleft. The ASD was closed primarily. The patient was weaned from CPB without difficulty using norepinephrine at 4 µg/min, and the PA catheter was advanced. The systolic blood pressure was 100/52, with central venous pressure of 5 and PA pressure of 32/15 (all measurements in mm Hg). TEE revealed trace MR, with no mitral SAM. The annuloplasty ring was seen to protrude into the LVOT, and color flow Doppler showed aliasing in the ascending aorta (Fig. 2), consistent with high velocity, turbulent flow. Continuous wave Doppler directed through the LVOT and aortic valve (AV) revealed a peak systolic gradient of 90 mm Hg (Fig. 3A). Pulsed wave Doppler examination showed the gradient to be near the annuloplasty ring. The right and noncoronary cusps of the AV were immobile. There was no aortic insufficiency. The surgeon measured simultaneous LV and aortic pressures a few minutes later, and found an LV pressure of 154, with an aortic pressure of 95 mm Hg. The patient was returned to CPB. Examination of the mitral repair revealed marked protrusion of the rigid annuloplasty ring into the LVOT, directly underneath the right and noncoronary cusps of the AV. The ring was removed. The ASD closure was converted from a primary repair to a patch closure to take tension off the suture line. The patient was weaned from CPB using milrinone at 0.5 µg · kg–1 · min–1, and norepinephrine at 6 µg/min. On TEE examination, there was initially mild MR, which decreased to trace MR after chest closure, and there was no obstruction of the LVOT (Fig. 4) or evidence of residual gradient between the LV and the aorta (Fig. 3B). Color flow Doppler evaluation of the interatrial septum revealed no evidence of residual interatrial shunt. The patient recovered uneventfully and was discharged from the hospital on the fifth postoperative day.
View larger version (132K):
[in this window]
[in a new window]
|
Figure 1. Baseline transesophageal echocardiography. A, Mid-esophageal four-chamber view showing an ostium primum atrial septal defect (arrowhead) and right heart enlargement. B, Mid-esophageal mitral commissural views showing a cleft anterior mitral leaflet. Left shows two-dimensional image of cleft (arrow) and right shows color flow Doppler of a large flow convergence indicating severe mitral regurgitation (arrowheads). LA = left atrium, LV = left ventricle, RA = right atrium, RV = right ventricle.
|
|
View larger version (61K):
[in this window]
[in a new window]
|
Figure 2. Transesophageal echocardiography mid-esophageal long-axis views after first cardiopulmonary bypass run. A, Two-dimensional image showing anterior aspect of mitral annuloplasty ring (arrowhead) protruding into the left ventricular outflow tract. The arrow indicates the posterior aspect of the ring. B, Color flow Doppler image showing high velocity, turbulent flow in the proximal ascending aorta (arrowheads) caused by the protruding annuloplasty ring (arrow). Asc Ao = ascending aorta, LA = left atrium, LV = left ventricle, RV = right ventricle.
|
|
View larger version (78K):
[in this window]
[in a new window]
|
Figure 3. Transesophageal echocardiography continuous wave Doppler velocity profiles through the left ventricular outflow tract from the transgastric long-axis view. A, Before mitral annuloplasty ring removal showing a peak outflow velocity of 4.8 m/s consistent with a gradient of 90 mm Hg. B, After ring removal showing a normal outflow velocity profile.
|
|
View larger version (141K):
[in this window]
[in a new window]
|
Figure 4. Transesophageal echocardiography mid-esophageal long-axis view after mitral annuloplasty ring removal showing no residual left ventricular outflow tract obstruction. LA = left atrium, LV = left ventricle, Ao = aorta.
|
|
|
Discussion
|
|---|
Immediately after mitral valve repair, TEE provides information about valve function, and numerous potential complications. The most common cause of failed mitral valve repair is mitral SAM (8,9), which has been reported after repairs with and without ring annuloplasties (10,11). Damage to the AV resulting in aortic regurgitation from mitral ring sutures has been reported (12,13), as well as late LVOT obstruction caused by pannus formation on prosthetic mitral valves and mitral annuloplasty rings (14,15). In the pediatric population, subaortic stenosis can occur as a late complication of atrioventricular septal defect repairs; it has not been reported in patients undergoing isolated ostium primum ASD closures (16,17).
We speculate that insertion of a rigid annuloplasty ring caused subaortic protrusion of the now rigid mitral annulus into the LVOT because of the presence of a partial endocardial cushion defect and abnormal fibrous mitral annulus. Although not reported with ostium primum ASD repairs, it is notable that protrusion of a rigid prosthetic mitral valve ring into the LVOT has been reported in complete endocardial cushion defects. Hemodynamic variables were acceptable immediately after CPB, and the severe obstruction of the LVOT was apparent only by TEE.
|
Footnotes
|
|---|
Supplemental material available at www.anesthesia-analgesia.org.
|
References
|
|---|
- Marwick TH, Stewart WJ, Currie PJ, Cosgrove DM. Mechanisms of failure of mitral valve repair: an echocardiographic study. Am Heart J 1991; 122: 149–56.[ISI][Medline]
- Kalman JM, Jones EF, Lubicz S, et al. Evaluation of mitral valve repair by intraoperative transesophageal echocardiography. Aust N Z J Med 1993; 23: 463–9.[ISI][Medline]
- Grimm RA, Stewart WJ. The role of intraoperative echocardiography in valve surgery. Cardiol Clin 1998; 16: 477–89.[Medline]
- Muratori M, Berti M, Doria E, et al. Transesophageal echocardiography as predictor of mitral valve repair. J Heart Valve Dis 2001; 10: 65–71.[ISI][Medline]
- Click RL, Abel MD, Schaff HV. Intraoperative transesophageal echocardiography: 5-year prospective review of impact on surgical management. Mayo Clin Proc 2000; 75: 241–7.[ISI][Medline]
- Agricola E, Oppizzi M, Maisano F, et al. Detection of mechanisms of immediate failure by transesophageal echocardiography in quadrangular resection mitral valve repair technique for severe mitral regurgitation. Am J Cardiol 2003; 91: 175–9.[ISI][Medline]
- Gillinov AM, Cosgrove DM. Mitral valve repair for degenerative disease. J Heart Valve Dis 2002; 11: S15–20.
- Maslow AD, Regan MM, Haering JM, et al. Echocardiographic predictors of left ventricular outflow tract obstruction and systolic anterior motion of the mitral valve after mitral valve reconstruction for myxomatous valve disease. Am J Cardiol 1999; 23: 2096–104.
- Freeman WK, Schaff HV, Khandheria BK, et al. Intraoperative evaluation of mitral valve regurgitation and repair by transesophageal echocardiography: incidence and significance of systolic anterior motion. Am J Cardiol 1992; 20: 599–609.
- Pasic M, Von Segesser L, Niederhauser U, et al. Outflow tract obstruction after mitral valve repair without an annuloplasty ring. Eur J Cardiothorac Surg 1995; 9: 283–5.[Abstract]
- Lopez JA, Schnee M, Gaos CM, Wilansky S. Left ventricular outflow tract obstruction and hemolytic anemia after mitral valve repair with a Duran ring. Ann Thorac Surg 1994; 58: 987–7;Discussion 877–8.
- Ducharme A, Courval J, Dore A, et al. Severe aortic regurgitation immediately after mitral valve annuloplasty. Ann Thorac Surg 1999; 67: 1487–9.[Abstract/Free Full Text]
- Hill AC, Bansal RC, Razzouk AJ, et al. Echocardiographic recognition of iatrogenic aortic valve leaflet perforation. Ann Thorac Surg 1997; 64: 684–9.[Abstract/Free Full Text]
- Ibrahim MF, David TE. Mitral stenosis after mitral valve repair for non-rheumatic mitral regurgitation. Ann Thorac Surg 2002; 73: 34–6.[Abstract/Free Full Text]
- Khoshnevis R, Barasch E, Pathan A, et al. Echocardiographic diagnosis of left ventricular outflow tract obstruction caused by an acquired subaortic membrane after mitral valve replacement. J Am Soc Echocardiogr 1999; 12: 319–23.[ISI][Medline]
- Van Arsdell GS, Williams WG, Boutin GA, et al. Subaortic stenosis in the spectrum of atrioventricular septal defects. J Thorac Cardiovasc Surg 1995; 110: 1534–41.[Abstract/Free Full Text]
- Lim DS, Ensing GJ, Ludomirsky A, et al. Echocardiographic predictors for the development of subaortic stenosis after repair of atrioventricular septal defect. Am J Cardiol 2003; 91: 900–3.[ISI][Medline]
Accepted for publication December 29, 2003.
This article has been cited by other articles:
|
|
|
|
 
K. Bendjelid, K. E. Glas, and J. S. Shanewise
ECG Monitoring Is Essential for Echocardiographic Analysis * Response
Anesth. Analg.,
January 1, 2005;
100(1):
294 - 296.
[Full Text]
[PDF]
|
|
|
Top
Abstract
Introduction
