Incidental Cor Triatriatum Sinister During Coronary Artery Bypass Surgery

Melnick, Abigail H. MD; Brzezinski, Marek MD; Mark, Jonathan B. MD

Anesthesia & Analgesia:
doi: 10.1213/01.ANE.0000175207.19332.6C
Cardiovascular Anesthesia: Echo Didactics & Rounds
Author Information

Department of Anesthesiology, Duke University Medical Center, Durham, North Carolina

Supplemental data available at

Accepted for publication March 2, 2005.

Address correspondence and reprint requests to Abigail H. Melnick, MD, Department of Anesthesiology, Box 3094, Duke University Medical Center, Durham, NC 27710. Address electronic mail to

Article Outline

A 64-yr-old man presented for elective coronary artery bypass graft surgery. He gave a 2-wk history of chest pain but denied symptoms of dyspnea or orthopnea. His medical history was significant for myocardial infarction 7 yr earlier, hypertension, and noninsulin dependant diabetes mellitus. Cardiac catheterization demonstrated three-vessel coronary artery disease and left ventricular (LV) end-diastolic pressure of 18 mm Hg. The preoperative chest radiograph was normal. Preoperative echocardiography was not performed.

Routine intraoperative transesophageal echocardiography (TEE) demonstrated a fenestrated membrane traversing the left atrium (LA) (Fig. 1A) (video loop available at Diastolic flow across the membrane was nonturbulent. All four pulmonary veins entered the LA proximal to the membrane (Fig. 1B), and the left atrial appendage (LAA) was distal to the membrane (Fig. 1C). The LA was not enlarged and the atrial septum was intact. The remainder of the TEE examination was unremarkable. The echocardiography findings were discussed with the surgical team, and a decision was made to resect the membrane using a transseptal approach through a right atriotomy in addition to performing the coronary revascularization (Fig. 2A). The TEE examination after resection of the membrane showed oscillating strand-like remnants of the membrane attached to the LA wall (Fig. 2B).

Cor triatriatum sinister is a rare congenital anomaly wherein, a fibromuscular membrane divides the LA into two chambers: the dorsal chamber receives the pulmonary veins and the ventral chamber contains the mitral valve and the LAA (1). Depending on the degree of communication between the chambers, the obstruction to left ventricular inflow can manifest clinically from infancy to late adulthood, with symptoms of pulmonary venous congestion that imitate mitral stenosis. The primary concern with cor triatriatum is the potential for LV inlet obstruction, leading to mitral stenosis physiology, although rarely pulmonary venous inflow can be compromised. The chest radiograph usually shows increased vascular markings, and a cardiac murmur is frequently noted. Some patients with cor triatriatum may remain asymptomatic, whereas others may have late onset of symptoms, possibly related to fibrosis and calcification of the membrane with associated atrial fibrillation or mitral regurgitation (2). Currently, TEE is the standard procedure for diagnosing this congenital anomaly (3), but its incidental intraoperative diagnosis presents a management dilemma because surgical excision exposes the patient to increased risk associated with an open-chamber procedure.

Appropriate TEE assessment of this condition should include the following key steps. The anatomy of the LA membrane should be defined and flow obstruction should be assessed using color flow Doppler. When obstruction is suspected from these images and any discreet jets of abnormal transmembrane or pulmonary venous flow are identified, spectral Doppler measurements can help quantify the hemodynamic impairment. In addition, pulmonary venous and atrial septal anatomy should be evaluated, as these may be abnormal in this condition. Although the preferred management of “incidental” cor triatriatum remains anecdotal at best, a comprehensive and accurate TEE examination undoubtedly will aid clinical decision making.

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1. Marin-Garcia J, Tandon R, Lucas RV Jr, Edwards JE. Cor triatriatum: study of 20 cases. Am J Cardiol 1975;35:59–66.
2. Chen Q, Guhathakurta S, Vadalapali G, et al. Cor triatriatum in adults: three new cases and a brief review. Texas Heart Inst J 1999;26:206–10.
3. Schluter M, Langenstein BA, Their W, et al. Transesophageal two-dimensional echocardiography in the diagnosis of cor triatriatum in the adult. J Am Coll Cardiol 1983;2:1011–5.
© 2005 International Anesthesia Research Society