Pediatr Cardiol I2:24-27, 1991

Pediatric Cardiology 9 Springer-VerlagNew York Inc. 1991

Right Heart Thrombus in Infants and Children K. K~td~.r, I. Harty~nszky, L. Kir~ly, and L. Bendig H u n g a r i a n Institute of Cardiology, S e m m e l w e i s University Medical School, Pediatric Department, No. l l, Heim P~.I Hospital, B u d a p e s t , H u n g a r y

SUMMARY. The echocardiographic features and management of 10 children with right heart thrombus (RHT) are presented. The patients' ages ranged from 2 weeks to 12 years. Three patients were less than 3 weeks old. The echocardiographic diagnosis was confirmed in five patients by surgery or autopsy. The thrombus was detected in the right atrium (five patients), in the right ventricle (three), on the tricuspid valve or within the inferior vena cava, the superior vena cava, or its extension following Senning's operation for transposition of great arteries (TGA). Seven patients had structural heart disease: TGA in four, tricuspid atresia in three. In two of three patients with anatomically normal heart, the thrombus occurred as a complication of a ventriculoatrial and a iymphovenous shunt system. The third patient had no predisposing factor. Five patients were treated with anticoagulants or platelet anti-aggregating agents and four by surgery. Seven patients survived and were followed by echocardiography. KEY WORDS: Right heart thrombus - - Echocardiography

Right heart thrombus (RHT) is a life-threatening disorder and has rarely been recognized before death. It frequently results in pulmonary embolism and may be responsible for cerebrovascular accidents in certain forms of congenital heart disease [10]. As far as we know, there are only single case reports in the literature of right heart thrombus diagnosed noninvasively in children [4, 5, 7-9, 12, 15]. During the period of 1984-1988, using two-dimensional echocardiography (2DE), we identified 10 cases with RHT. Because the clinical significance of RHT detected by 2DE is unclear, we retrospectively analyzed the clinical features, predisposing factors, management, and outcome of our cases.

Methods 2DE was performed with a Hewlett-Packard phased array 77020A S y s t e m and a 2.5 or 5 M H z transducer. Standard transd u c e r positions were u s e d to obtain sections in the standard imaging planes.

Address offprint requests to." H u n g a r i a n Institute of Cardiology, S e m m e l w e i s University Medical School, Pediatric D e p a r t m e n t , No. 11, H e i m P~.I Hospital, B u d a p e s t , H u n g a r y .

Patients During the period of 1984-1988, we performed a total of 6244 2DE studies. We diagnosed R H T in 10 patients. Only three of these had been sent urgently for 2DE investigation because of the suspicion of an intracardiac t h r o m b u s . In the others, 2DE was performed to a s s e s s left ventricular function, the effect of a Rashkind s e p t o s t o m y , or to exclude a congenital heart defect. The patients' age ranged from 2 weeks to 12 years. Three patients were less than 3 w e e k s old. T h e 2DE diagnosis was confirmed in five patients by surgery or autopsy; seven survivors were followed by 2DE for 1-3 years.

Results Clinical features and other data are listed in Table 1. Three patients with transposition of the great arteries (TGA) were 1-2 weeks of age, after Rashkind septostomy, and one was 3 months old, after a Senning operation. Among the patients with tricuspid atresia, one had had a Waterston-Cooley anastomosis and two a Fontan operation (Figs. 1 and 2). In two of the three patients with anatomically normal heart, RHT occurred as a complication of a ventriculoatrial (Pudenz) shunt and a lymphovenous shunt (Lee-Ven) system, respectively. The third patient, a 3-week-old preterm baby, had multiple thrombi on the tricuspid valve. He had not had an

K~id~iret al.: Right Heart Thrombus

Fig. 1. (A) Two-dimensional echocardiogram demonstrating right atrial thrombus (arrows) in a 5-year-old child, 1 year after Fontan procedure. (B) After 10 days of anticoagulant therapy, the thrombus is absent. RA, right atrium; LA, left atrium. Fig. 2. A large thrombus in the right atrium in a 2-year-old child with tricuspid atresia confirmed by surgery. Fig. 3. (A) Right atrial thrombus 5 days after Rashkind septostomy. (B) Autopsy showed the thrombus formed on atrial septa and right atrial posterior wall. RA, right atrium; LA, left atrium.

indwelling line or any other known predisposing factor. Five patients were treated with anticoagulants or antiplatelet aggregation agents and four by surgery. In two patients, an e m e r g e n c y operation was performed because of sudden cardiovascular collapse (patients 1 and 8). Both children died. The third patient, an infant, was sent for operation because the multiple mobile thrombi on the tricuspid valve caused transient neurologic episodes, presumably from paradoxical emboli through a patent foramen ovale [6]. A fourth patient had a L e e - V e n shunt system which was changed because it had thrombus formation on its end. Both these children are alive. Only one child, an infant, died in the ini-

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tial cerebral attack after a Rashkind septostomy. Autopsy confirmed the presence of a right atrial thrombus as seen on 2DE (Fig. 3A and B). In Table 2, 2DE features of R H T in our patients are presented.

Discussion 2DE is a useful m e t h o d in the early detection of major cardiac thrombi: the early and accurate identification of R H T by 2DE may provide important therapeutic and prognostic information [1, 14]. In our study, R H T was surprisingly c o m m o n (0.015% of 6244 2DE studies). The importance of 2DE in recognizing R H T is demonstrated by the fact that previously only three of 10 patients had been suspected clinically o f having intracardiac thrombi. Assessing the predisposing factors for R H T , we found that in two patients (nos. 8 and 9) the thrombus formation may have been a direct consequence of shunt systems. T w o patients (nos. I and 4) had blood flow stasis (inferior vena cava thrombosis and polycythemia). The other three infants (nos. 4-6) had had a balloon atrial septostomy 2 weeks before the right atrial thrombi were detected. The postoperative patients (Fontan, Senning) were examined 6-18 months after the p r o c e d u r e (nos. 2, 3, and 7).

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Pediatric Cardiology Vol. 12, No. 1, 1991

Table 1. Clinical and other features of patients with RHT

Patients

Age

1. K.E.

2 years

2. F.G.

3 years

3. V.K.

5 years

4. 5. 6. 7.

2 3 2 5

M.T. P.E. P.J. M.P.

weeks weeks weeks years

8. B.A.

5 years

9. F.I.

12 years

10. L.D.

3 weeks

Cardiac anatomy

Position of thrombus

Treatment

Outcome

TA Waterston TA Fontan TA Kreutzer TGA TGA TGA TGA Senning Normal Pudenz shunt Normal Lee-Ven shunt Normal

RA IVC

Surgery

Died at operation

RA

AP

Alive

RA

H/AC

Alive

RA RV RA SVC channel

0 AC H/AC AC

Sudden death Alive Alive Alive

RA SVC

Surgery

RV

Change of cath.

Died postoperatively, low cardiac output Alive

TV RV

Surgery

Alive

0, no treatment; AC, acenocoumarol; H, heparin; AP, antiplatelet drugs: TV, tricuspid valve; RV, right ventricle; RA, right atrium; SVC, superior vena cava; IVC, inferior vena cava; TGA, transposition of great arteries: TA, tricuspid atresia.

Table 2. Echocardiographic features of thrombi

evidence of an extracardiac origin of RHT. All infants with T G A were catheterized via the femoral Patient Position 2DE features" vein, but also had intracardiac manipulations no. of thrombus (Rashkind septostomy). We sent patients for emergency surgery when 1 RA 1VC "Snake-like," M, huge the thrombi were very large, highly mobile, or they 2 RA "Snake-like," NM, small 3 RA "Snake-like," NM, large had an impaired cardiac state. In spite of the high 4 RA "Snake-like," NM, small risk of operative therapy, we believe that surgery 5 RV "Snake-like," NM, small should be performed immediately and that it is po6 RA "Snake-like," NM, small tentially life-saving in patients with sudden cardio7 SVC channel "'Snake-like," NM, small vascular collapse. 8 RA, SVC Laminated in IVC, NM, large in RA In conclusion, T G A and tricuspid atresia are 9 RV NM, small, on Lee-Van shunt 10 TV, RV "high-risk a n o m a l i e s " for R H T even after surgery. M, huge, multiplex thrombi on TV and in RV R H T can be treated successfully by anticoagulants, but in some circumstances (mobile, very large RA, right atrium; tVC, inferior vena cava; RV, right ventricle; thrombi, neurological attacks) urgent surgery is SVC, superior vena cava; TV, tricuspid valve; M, mobile, NM, necessary. R H T can occur in an anatomically nornonmobile. mal heart without any known risk factors. ~ Small, 2 cm.

In one patient tqo. I0) no predisposing factor was identified. The management of R H T is still controversial. Some investigators [2, 16] have suggested that R H T may be treated with anticoagulants. Others [8, 18] preferred streptokinase. Most adults with extensive R H T , but no previous surgery, had died of pulmonary embolism [3, 11, 13, 17]. The mobile R H T probably originates in the venous system, in contrast to nonmobile R H T , which usually forms in situ because of decreased blood flow or intracardiac foreign bodies. The latter seem to have a better prognosis [3, 12]. In our series we could not find any

Addendum. Two more cases of RHT have been diagnosed since completion of this study. Both had cyanotic congenital heart disease, namely TGA and tetralogy of Fallot. Some of our cases have been incorporated into the European Cooperative Study reported by G. Kronik [(1989) Euro Heart J 10:1046-1059].

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K~d~ir et al.: Right Heart Thrombus

3. Covarrubias EA, Sheikh MU, Fowx LM (1977) Echocardiography and pulmonary embolism. A n n Intern M e d 87:720 4. Delaplane D, Scott JP, Riggs TW, et al. (1982) Urokinase therapy for a catheter related right atrial thrombus. J Pediatr 100:149 5. Grollier G, Gerard JL, Commeau P, et al. (1986) Thromboses des cavites cardiaques diagnostic echocardiographique et indications therapeutiques a propos de 2 cas et d'une revue de la litterature. Can J Cardiol 2:68 6. Harty~inszky IL, K~id~.r K, H/Jttl T, S~pi E, Lozs~idi K (1989) Thrombotic lesions of the tricuspid valve in a newborn surgical management. Pediatr Cardiol 10:109-112 7. Keck EW, Fiege M, Riesner K (1978) Pulmonarer Hochdruck and cot pulmonale als Komplikationen eines ventriculovasalen Shunts bei Hydrocephalus. Herz 3:120 8. Ouyang P, Camara EJ, Jain A, et al. (1983) Intracavity thrombi in the right heart associated with multiple pulmonary emboli. Chest 84:84 9. Pham MG, Mc Gough EC, Nixon GW, et al. (1979) Right atrial ball valve thrombus a complication in an infant. J Thoracic Cardiovasc Surg 78:579 10. Pietro DA, Parisei AF (1980) Intracardiac masses: Tumors, vegetations, lhrombi and foreign bodies. M e d Clin North A m 64:239 I I. Redish GA, Anderson AL (1983) Echocardiographic diagnosis of right atrial thromboembolism. J A m Coil Cardiol 4:1167

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12. Riggs T, Milton H, De Leons et al. (1981) Two-dimensional echocardiography in evaluation of right atrial masses five cases in pediatric patients. A m J Cardio148:961 13. Rosenznweig MS, Nanda DC (1982) Two-dimensional echocardiographic detection of circulating right atrial thrombi. A m Heart J 103:435 14. Schmalz AA, Heunges R, Hell RP (1980) Thrombosis and embolism complicating ventriculoatrial shunt for hydrocephalus echocardiographic findings. Br H e a r t J 43:241 15. Shannon FL, Campbell DN, Clarke DR (1986) Rare complication of the modified Fontan procedure. Pediatr Cardiol 7:209 16. Shiu MF, Abrams LD (1983) Echocardiographic feature of free floating thrombus mimicking right ventricular myxoma. Br H e a r t J 49:612 17. Starkey 1R, DeBono DPL (1982) Echocardiographic identification of right sided cardiac intracavitary thromboembolus in massive pulmonary embolism. Circulation 66:1322 18. Stowers SA, LeiboffRH, Wasserman AG, et al. (1983) Right ventricular thrombus formation in association with acute myocardial infarction diagnosis by two-dimensional echocardiography. A m J Cardiol 52:912 19. Torbicki A, Pasierski T, Uchman B, et al. (1987) Two-dimensional echocardiographic diagnosis and clinical outcome. Cor Vasa 4:293