To the Editor:
The report of right pulmonary artery-to-left atrium (PA-to-LA) communication by Alexi-Meskishvili and colleagues 1 (June 2001) was interesting, but we would like to differ with some of their observations by means of comparison with a similar case that we reported earlier. 2 Further, we present the transesophageal findings of the lesion that we reported at that time. 2
A 19-year-old patient presented at Sri Sathya Sai Institute of Higher Medical Sciences (Puttaparthi, India) with cyanosis that had been progressive from childhood. Transthoracic echocardiography showed color flow into the LA. Injection of agitated saline into the cubital vein showed the contrast filling the LA, immediately after entering the PA. Transesophageal echocardiography delineated a vessel arising from the right PA and entering the LA. Color-flow mapping showed the direction of flow from the right PA to the LA (Fig. 1). A type I PA-to-LA communication was diagnosed noninvasively. There were no other intracardiac lesions. A PA angiogram was done for confirmation.
Fig. 1 Color-flow mapping upon transesophageal echocardiography shows drainage of the right pulmonary artery (RPA) into the left atrium (LA).
(From: Krishnamoorthy KM, Rao S. Pulmonary artery to left atrial fistula. Eur J Cardiothorac Surg 2001;20:1052–3. ©2001 Elsevier Science. Reproduced with permission from Elsevier Science.)
A right thoracotomy was performed through the 3rd intercostal space. Upon dissecting the right PA, we saw an anomalous vessel arising from its posteroinferior aspect after its right lower lobe branch. This tract (1.5-cm diameter) was traced and seen to enter the LA posterolaterally, separate from and superior to the opening of the right lower pulmonary vein. The right PA branched normally, distal to the anomalous vessel. On clamping the communication, we saw the oxygen saturation rise to 99.8% within 3 minutes. The anomalous vessel was simply ligated (without cardiopulmonary bypass), which resulted in a complete cure.
In differing with the authors, we would like to make the following points: 1) although angiography is considered essential, 3 we made the diagnosis noninvasively by contrast injection and TEE; 2) diagnosis of a right pulmonary artery-to-left atrium communication is not difficult if one has a high index of suspicion in the presence of cyanosis, few or no precordial findings, normal 2nd heart sound, and a shadow parallel to the cardiac border on the chest radiograph; 3) there may be no associated lesions; and 4) ligation or division of the anomalous vessel (without bypass) is sufficient, being simple and curative. 3 Cardiopulmonary bypass is required if dissection of the vessel is technically difficult, 4 or if biopsy of the vessel is performed. 3
References
- 1.Alexi-Meskishvili V, Dahnert I, Ovroutski S, Hetzer R. Right pulmonary artery-to-left atrium communication: a rare cause of systemic cyanosis. Tex Heart Inst J 2001;28:122 [PMC free article] [PubMed]
- 2.Krishnamoorthy KM, Rao S. Pulmonary artery to left atrial fistula. Eur J Cardiothorac Surg 2001;20:1052–3. [DOI] [PubMed]
- 3.Ohara H, Ito K, Kohguche N, Ohkawa Y, Akasaka T, Takarada M, et al. Direct communication between the right pulmonary artery and the left atrium. A case report and review of the literature. J Thorac Cardiovasc Surg 1979;77: 742–7. [PubMed]
- 4.Abe T, Kuribayashi R, Sato M, Nieda S. Direct communication of the right pulmonary artery with the left atrium. A case report and review of the literature. J Thorac Cardiovasc Surg 1972;64:38–44. [PubMed]