We read with great interest the excellent case report by Espeel et al.  1that describes two patients experiencing pulmonary embolism with additional extrapulmonary thrombi requiring surgical intervention. The positive outcome of both patients corroborates the favorable experience in patients from our institution undergoing surgical pulmonary embolectomy.2We agree with the authors that intraoperative transesophageal echocardiography is a relatively safe and noninvasive diagnostic modality that allows early detection of intracardiac thrombi. However, we were surprised that the importance of transesophageal echocardiography for the guidance of surgical extraction was not emphasized in this case report. We recently demonstrated that extrapulmonary thromboemboli can be present in the right heart and the vena cava in up to 26% of all patients with massive pulmonary embolism undergoing pulmonary embolectomy.3Such extrapulmonary thromboemboli may have a significant impact on the surgical procedure, because they may influence cannulation placement and surgical technique during the operation. For example, it may become necessary to perform circulatory arrest in order to evacuate thrombi from the inferior vena cava. Moreover, extrapulmonary thromboemboli that remain unrecognized and are not surgically removed can become the source of recurrent pulmonary embolism.4Therefore, we believe that intraoperative transesophageal echocardiography is not only an excellent tool for hemodynamic monitoring5and management of acute right heart failure6during surgical pulmonary embolectomy, but should also be considered an important diagnostic tool to detect concurrent extrapulmonary thrombi and should guide their surgical extraction.

*Brigham and Women's Hospital, Harvard Medical School, Boston, Massachusetts. prosenberger1@partners.org

1.
Espeel B, Crispin V, Fraselle B, Payen B, Versailles H: Floating thrombus entrapped in a patent foramen ovale complicating acute pulmonary embolism. Anesthesiology 2005; 103:895–7
2.
Aklog L, Williams CS, Byrne JG, Goldhaber SZ: Acute pulmonary embolectomy: A contemporary approach. Circulation 2002; 105:1416–9
3.
Rosenberger P, Shernan SK, Mihaljevic T, Eltzschig HK: Transesophageal echocardiography for detecting extrapulmonary thrombi during pulmonary embolectomy. Ann Thorac Surg 2004; 78:862–6
4.
Rosenberger P, Shernan SK, Rawn JD, Scott J, Eltzschig HK: Critical role of inferior vena caval filter placement after pulmonary embolectomy. J Card Surg 2005; 20:289–90
5.
Rosenberger P, Shernan SK, Body SC, Eltzschig HK: Utility of intraoperative transesophageal echocardiography for diagnosis of pulmonary embolism. Anesth Analg 2004; 99:12–6
6.
Eltzschig HK, Zwissler B, Felbinger TW: Perioperative implications of heart transplantation. Anaesthesist 2003; 52:678–89