Ann Thorac Surg 1999;68:1838-1840
© 1999 The Society of Thoracic Surgeons
Case Reports
Hemolytic anemia after atrioventricular septal defect repair without synthetic material
John C. Tsang, MDa,
Dominique Shum-Tim, MDa,
Christo I. Tchervenkov, MDa,
Luc Jutras, MDb,
Brian Sinclair, MDb
a Department of Cardiovascular Surgery, The Montreal Children’s Hospital, McGill University, Montreal, Quebec, Canada
b Department of Cardiology, The Montreal Children’s Hospital, McGill University, Montreal, Quebec, Canada
Address reprint requests to Dr Tchervenkov, Department of Cardiovascular Surgery, The Montreal Children’s Hospital, 2300 Tupper St, Room C-829, Montreal, PQ H3H JP3, Canada
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Abstract
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We report a rare case of severe hemolytic anemia following repair of a congenital heart defect without the use of prosthetic material. A review of the literature, diagnosis, and management are described. Although this is an unusual complication following congenital heart surgery, a high index of suspicion must be maintained and a possible mechanical cause should be sought and corrected.
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Introduction
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Hemolytic anemia is an infrequent but well-documented complication associated with intravascular or intracardiac prosthesis. With the improvement of surgical materials and techniques, this complication has recently become exceptionally rare. We describe an infant who developed severe hemolysis after primary repair of an atrioventricular septal defect (AVSD) without synthetic materials.
A newborn girl with trisomy 21 was diagnosed with a large AVSD (Rastelli type A). At 2 months of age, she underwent a primary intracardiac repair through median sternotomy using a single untreated pericardial patch closure of the AVSD and stitch closure of the left atrioventricular (AV) valve cleft. Postoperative transthoracic echocardiography (TTE) revealed good biventricular function with mild-to-moderate left-AV valve regurgitation, but no evidence of residual atrial (ASD) or ventricular septal defect (VSD).
The patient was well until 6 weeks postoperatively, when she was admitted to The Children’s Hospital of Eastern Ontario with bronchiolitis. At this time she was noted to have had a decrease in hemoglobin from 104 g/L to 85 g/L. She was stable and was subsequently discharged for further work-up of her normochromic, normocytic anemia as an outpatient. She was readmitted to the hospital 3 weeks later with influenza A viral illness. Upon admission, she was noted to have had a further significant decline in hemoglobin to 52 g/L. Subsequent work-up revealed elevated reticulocyte count at 8% (normal 0.2%–2%), increased schistocytes on peripheral blood smear indicating fragmentation of red cells, a lactate dehydrogenase (LDH) of 6260 U/L (normal 470–920 U/L), and a low haptoglobin level of less than 0.12 g/L (normal 0.50–3.20 g/L). Antibody screening revealed no abnormal autoantibodies and Coombs test was negative. Urinalysis demonstrated moderate amounts of hemoglobin but iron stains were negative. Repeat TTE was unchanged from the previous echocardiography. The diagnosis of mechanical hemolytic anemia due to left-AV valve regurgitation was entertained. Despite a trial of medical treatment with Lasix (Hoechst Marion Roussel, Kansas, MO), iron, ferritin supplements, and blood transfusions, the anemia persisted and it was decided to reoperate.
An intraoperative transesophageal echocardiography (TEE) confirmed the preoperative findings (Figure 1A). A right thoracotomy approach was elected to facilitate the mitral valve exposure without having to extensively mobilize the heart through a repeat median sternotomy. The patient was cannulated through bicaval and ascending aorta for cardiopulmonary bypass (CPB) support. Following cardioplegic arrest of the heart, inspection of the left atrium revealed an intact and completely endothelialized patch with no interventricular communication. The left-AV valve cleft which had been partially reapproximated previously was further closed with two interrupted pledgeted sutures. An annuloplasty was performed by plicating the two commissures. Examination of the left-AV valve by volume loading of the left ventricle with saline did not reveal any significant regurgitation and the patient was easily weaned off CPB. A repeat TEE confirmed that the central regurgitation jet had resolved. However, a previously unidentified, narrow, high-velocity regurgitant jet, originating anteriorly near the aortic valve area and projecting posteriorly along the floor of the left atrium to strike the left atrial septum, was identified (Figure 1B). Cardiopulmonary bypass was resumed and the left atrium re-exposed. Upon everting traction of the crevice formed by the left-AV valve annulus in the subaortic area, a 2 x 1 mm, slit-like defect was identified. This was at the junction of the left superior leaflet attachment to the pericardial patch. The defect was caused by a Prolene suture (Ethicon, Somerville, NJ) which had cut through the leaflet tissue. This defect was closed with a single pledgeted horizontal mattress suture. Subsequently, the TEE showed trivial residual left-AV valve regurgitation and the narrow high velocity jet had completely resolved. The patient had an uneventful recovery with no further blood transfusion requirements. Early postoperative and 6-week follow-up investigations revealed an increasing hemoglobin of 120 g/L, no schistocytes, normal LDH of 793 U/L, haptoglobin of 0.85 g/L, and no further hemoglobinuria on urinalysis. Repeat TTE showed no residual left-AV valve regurgitation.
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Fig 1. (A) Intraoperative transesophageal echocardiography showed moderate left-AV valve regurgitation consisting of a broad jet through the medial aspect of the valve and a more discrete jet related to the residual cleft. (LA = left atrium; LV = left ventricle.) (B) Second intraoperative transesophageal echocardiography showed narrow, high-velocity regurgitant jet originating anteriorly near the aortic valve area and projecting posteriorly along the floor of the left atrium to strike the left atrial septum. (Ao = aorta; LA = left atrium; RV = right ventricle.)
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Comment
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Clinically significant hemolysis following cardiac surgery is uncommon. In congenital heart surgery, only 14 cases have been reported in the English literature over the past 30 years. The majority (10) of these cases were reported between the early 1970s and early 1980s. These reports commonly involved the use of prosthetic material (Teflon, Impra Inc, subsidiary of C.R. Bard, Tempe, AZ and Dacron, C.R. Bard, Haverhill, PA) for the repairs. The hemolysis was commonly due to traumatic blood contact with the prosthetic material caused by residual defects [1].
There have been only four cases over the past 30 years where hemolysis was described in patients following surgery for congenital heart disease in the absence of prosthetic materials. The first case involved a newborn baby with L-TGA, pulmonary stenosis, and VSD, palliated with a classic right Blalock-Taussig (B-T) shunt. At 7 1/2 months of age it was noted that the patient was severely jaundiced, requiring repeated transfusions. Following a Rastelli repair and ligation of the B-T shunt, the hemolysis resolved [2]. A second case was among Capouya and associates’ series of 105 patients with AVSD [3]. Although the details of this particular case were not evident from the original report, 1 patient required several reoperations and eventual left-AV valve replacement for severe refractory valve-related hemolysis. A third case involved a congenital mitral cleft defect that continued to cause hemolysis following cleft closure due to residual mitral regurgitation. The patient subsequently required a mitral valve replacement prior to resolution of the hemolysis [4]. The last case involved a patient with hemolysis due to a coarctation which resolved following repair [5].
In the present case, there was no prosthetic material used in the repair. An untanned pericardium with the visceral surface placed toward the left atrium was used. Inspection of the pericardium revealed no denuding of the endothelium, which has previously been shown to be a potential source of hemolysis following intracardiac repairs [6]. The most likely source of the hemolysis was the small, 2- x 1-mm defect located adjacent to the left ventricular outflow tract. This was identified by the intraoperative TEE only after the central regurgitation was repaired, removing the regurgitant flow that masked this jet on the color Doppler image. The high velocity of the jet through this narrow orifice most likely produced turbulent flow and resulted in a high shearing stress on the red blood cells. It has been shown that shearing stresses of 3000 dynes/cm2 are enough to destroy erythrocytes [7]. The hemolysis itself may have perpetuated the process as the subsequent anemia increased the stroke volume and shear stress. Mechanical hemolysis is characterized by: normochromic, normocytic anemia; schistocytosis; low serum haptoglobin; and elevated LDH. The bone marrow shows hyperactivity of the erythroid series reflected in an elevated reticulocyte count as documented in this patient. More extreme hemolysis will produce hemoglobinuria and hemosiderinuria. The present case confirmed other reports that in the presence of severe hemolytic anemia, a mechanical cause should be investigated. While the presence of a foreign material greatly facilitates this diagnosis, a high index of suspicion should also be maintained in the rare cases where prosthetic material was not used, but an area of high pressure gradient was involved. When the confounding mechanical factor is not always obvious, surgical exploration may be necessary. The definitive treatment is surgical repair of the anatomical defect.
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References
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Schroeder J., Albert J., Clarke D., Schaffer M., Wolfe R., Hays T. Hemolysis due to branch pulmonary stenosis after the arterial switch procedure. Ann Thorac Surg 1991;51:491-492.[Abstract]
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Kinney J.B., Jr, DeSantes K., Abelson H.T., Stevenson J.G. Severe intravascular hemolysis in an infant with cyanotic congenital heart disease. J Pediatr 1990;117:911-914.[Medline]
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Capouya E.R., Laks H., Drinkwater D.C., Pearl J.M., Milgalter E. Management of the left atrioventricular valve in the repair of complete atrioventricular septal defects. J Thorac Cardiovasc Surg 1992;104:196-203.[Abstract]
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Moisey C.U., Manohitharajah S.M., Tovey L.A.D., Deverall P.B. Hemolytic anemia in a child in association with congenital mitral valve disease. J Thorac Cardiovasc Surg 1972;63:765-768.[Medline]
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Ravenel S.D., Johnson J.D., Sigler A.T. Intravascular hemolysis associated with coarctation of the aorta. J Pediatr 1969;75:67-73.[Medline]
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Ersley A.J. Traumatic cardiac hemolytic anemia. In: Williams W.J., Beutler E., Ersley A.J., Lichtman M.A., eds. Hematology, 4th ed. New York: McGraw-Hill Book Co, 1990:656.
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Nevaril C.G., Lynch E.C., Alfrey C.P., Hellums J.D. Erythrocyte damage and destruction induced by shearing stress. J Lab Clin Med 1968;71:784-790.[Medline]
Accepted for publication March 31, 1999.
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Abstract
Introduction
