HOME HELP FEEDBACK SUBSCRIPTIONS ARCHIVE SEARCH TABLE OF CONTENTS		QUICK SEARCH:   [advanced] Author: Keyword(s): Year:  Vol:  Page:

This Article Full Text (PDF) Alert me when this article is cited Alert me if a correction is posted Citation Map Services Email this article to a friend Similar articles in this journal Similar articles in PubMed Alert me to new issues of the journal Add to Personal Folders Download to citation manager Author home page(s): Naoki Yoshimura Takuro Misaki Permission Requests Citing Articles Citing Articles via HighWire Citing Articles via Google Scholar Google Scholar Articles by Murakami, H. Articles by Misaki, T. Search for Related Content PubMed PubMed Citation Articles by Murakami, H. Articles by Misaki, T.

J Thorac Cardiovasc Surg 2006;132:1235-1236
© 2006 The American Association for Thoracic Surgery

Brief Communication

Collision of the caval flows caused early failure of the Fontan circulation

^a First Department of Surgery, Faculty of Medicine, University of Toyama, Toyama, Japan
^b First Department of Pediatrics, Faculty of Medicine, University of Toyama, Toyama, Japan.

Received for publication June 23, 2006; accepted for publication August 11, 2006.

^_* Address for reprints: Hirohisa Murakami, MD, First Department of Surgery, Faculty of Medicine, University of Toyama, Toyama 2630, Sugitani, Toyama, 930-0194, Japan. (Email: murahisa{at}med.u-toyama.ac.jp).

In 1988, de Leval and colleagues¹ demonstrated the importance of fluid dynamics in Fontan circulation. They developed the total cavopulmonary connection (TCPC), which has hemodynamic advantages compared with the traditional atriopulmonary connection. In regard to the hemodynamics of the cavopulmonary anastomosis, several studies demonstrated that collision of caval flows at the connection resulted in high dissipative energy losses and that introduction of an offset between the superior vena cava (SVC) and the inferior vena cava (IVC) inlets reduced those losses.^2,3 We describe an early failure of the Fontan circulation caused by collision of the caval flows.

Clinical Summary

The patient was a 2-year-old girl with a diagnosis of tricuspid atresia made soon after birth, for which a bidirectional Glenn (BDG) anastomosis was performed at the age of 7 months. Preoperative catheterization data showed a mean pulmonary artery (PA) pressure of 13 mm Hg, pulmonary vascular resistance of 3.8 U/m², Nakata's PA index of 252, and left ventricular ejection fraction of 58%. Angiography showed that mitral valve regurgitation was not present. The site of the BDG anastomosis was deviated to the left side over the vertebra (Figure 1), suggesting that a Fontan-type operation could be safely performed. Two months after the catheterization, extracardiac TCPC was completed with interposition of an expanded polytetrafluoroethylene graft (18 mm) between the right PA and the IVC. After Fontan circulation was established, the patient demonstrated low cardiac output syndrome; her heart rate was 190 beats/min and systolic blood pressure ranged from 50 to 60 mm Hg. Despite the use of inhaled nitric oxide therapy, the transpulmonary pressure gradient between the central venous pressure (17-19 mm Hg) and the left atrial pressure (2-3 mm Hg) increased. Immediate echocardiography showed marked dilatation of the IVC and collapse of the left ventricular cavity. No blood flow was detected in the extracardiac conduit. Urgent angiography was performed. Impingement of SVC flow onto IVC flow and marked stagnation of blood flow in the conduit were seen (Figure 2). Urgent reoperation was performed with cardiopulmonary bypass. After division of the BDG, the anastomosis between the conduit and the right PA was intact, and no thrombus was observed in the conduit through the incision of the PA. The BDG anastomosis was transferred to the right side to avoid significant collision of the caval inlet flows, which was speculated to be the cause of acute failure of the Fontan circulation. Subsequently, the patient's hemodynamics significantly improved. Postoperative echocardiography showed that both the SVC and IVC flows smoothly passed toward the PA. Both the left ventricular volume and the IVC diameter became normal. Although the patient had a severe chylothorax, which required prolonged pleural drainage and a fat-restricted diet, she was discharged in good condition.

View larger version (194K): [in this window] [in a new window]   Figure 1. Angiography of the SVC anastomosis to the PAs shows that the BDG is shifted to the left side over the center of the vertebrae.

View larger version (87K): [in this window] [in a new window]   Figure 2. A, Urgent angiography 15 seconds after injection of contrast medium shows the marked delay of blood flow from the conduit to the IVC. The tip of the catheter was located in the left PA, and the contrast medium was washed out immediately by blood flow from the BDG. B, At 30 seconds after injection. The contrast medium was stagnant.

A computational simulation model by de Leval and colleagues¹ demonstrated that flow competition between the SVC and the IVC can occur in TCPC. They also reported a decrease in dissipated power with an increase of at least 1.0 cm in caval offset. In vitro flow experiments by Sharma and colleagues⁴ showed that as the offset is increased from 0.0 to 0.5 SVC diameters, the power losses decrease significantly. However, there is no report of an actual patient with early failure of the Fontan circulation caused by collision of the SVC and IVC flows. In our case, the addition of an offset dramatically improved the Fontan circulation. Gentles and colleagues⁵ described that unexpected low cardiac output was noted in 20 of 500 patients (4.0%) undergoing the Fontan operation. They did not refer to the caval offset; however, early failure of the Fontan circulation might have been the result of dissipative energy losses of caval return in these patients.

Sharma and colleagues⁴ advocated that surgical strategies for these patients should include a caval offset of 1.0 to 1.5 diameters optimally. Although anatomic space constraints in some clinical situations may allow only a minimal offset, we should try to design an adequate anastomosis to prevent significant energy losses.

Conclusion

We describe a patient with early failure of the Fontan circulation caused by collision of the caval flows. The addition of caval offset dramatically improved the Fontan circulation. Our clinical experience showed that energy losses in blood flow might be an important factor that may impair the Fontan circulation.

References

1. de Leval MR, Kilner P, Gewillig M, Bull C. Total cavopulmonary connection: a logical alternative to atriopulmonary connection for complex Fontan operations. J Thorac Cardiovasc Surg 1988;96:682-695.[Abstract]
   
2. de Leval MR, Dubini G, Migliavacca F, Jalali H, Camporini G, Redington A, et al. Use of computational fluid dynamics in the design of surgical procedures: application to the study of competitive flows in cavopulmonary connections. J Thorac Cardiovasc Surg 1996;111:502-513.[Abstract/Free Full Text]
   
3. Ensley A, Lynch P, Chatzimavroudis G, Lucas C, Sharma S, Yoganathan A. Toward designing the optimal total cavopulmonary connection: an in vitro study. Ann Thorac Surg 1999;68:1384-1390.[Abstract/Free Full Text]
   
4. Sharma S, Goudy S, Walker P, Panchal S, Ensley A, Kanter K, et al. In vitro flow experiments for determination of optimal geometry of total cavopulmonary connection for surgical repair of children with functional single ventricle. J Am Coll Cardiol 1996;27:1264-1269.[Abstract]
   
5. Gentles TL, Mayer JE, Gauvreau K, Newburger JW, Lock JE, Kupferschmid JP, et al. Fontan operation in five hundred consecutive patients: factors influencing early and late outcome. J Thorac Cardiovasc Surg 1997;114:376-391.[Abstract/Free Full Text]
   

This article has been cited by other articles:

				K. Itatani, K. Miyaji, T. Tomoyasu, Y. Nakahata, K. Ohara, S. Takamoto, and M. Ishii Optimal conduit size of the extracardiac Fontan operation based on energy loss and flow stagnation. Ann. Thorac. Surg., August 1, 2009; 88(2): 565 - 572. [Abstract] [Full Text] [PDF]

				D. D. Soerensen, K. Pekkan, D. de Zelicourt, S. Sharma, K. Kanter, M. Fogel, and A. P. Yoganathan Introduction of a New Optimized Total Cavopulmonary Connection Ann. Thorac. Surg., June 1, 2007; 83(6): 2182 - 2190. [Abstract] [Full Text] [PDF]

This Article Full Text (PDF) Alert me when this article is cited Alert me if a correction is posted Citation Map Services Email this article to a friend Similar articles in this journal Similar articles in PubMed Alert me to new issues of the journal Add to Personal Folders Download to citation manager Author home page(s): Naoki Yoshimura Takuro Misaki Permission Requests Citing Articles Citing Articles via HighWire Citing Articles via Google Scholar Google Scholar Articles by Murakami, H. Articles by Misaki, T. Search for Related Content PubMed PubMed Citation Articles by Murakami, H. Articles by Misaki, T.