1. Congenital Absence of the Pericardium Lane R. Miller, MD*, Tehreen Khan, MD, Reynolds Delgado, MD, and Raymond F. Stainback, MD Department of Cardiology, Texas Heart Institute at St. Luke’s Episcopal Hospital, Houston, TX Address for correspondence: Raymond F. Stainback, MD, Department of Cardiology, St. Luke’s Episcopal Hospital, Houston, TX 77030; phone: 832-355-6676; FAX: 932-355- 8374; e-mail: rstainback@sleh.com. © 2001-2002 Texas Heart Institute Cardiac Society

2. A 41-year-old black man presented with severe congestive heart failure. Following an extensive workup, idiopathic dilated cardiomyopathy was diagnosed. The patient’s echocardiogram was remarkable for marked anterior rotation of the right-sided chambers, yielding the unusual appearance of a 4-chamber view in the parasternal long-axis window (Figure 1). This abnormal cardiac orientation, which has been reported in patients with congenital absence of the pericardium, was confirmed in this case by cardiac magnetic resonance imaging (MRI) (Figure 2). Despite aggressive medical therapy, the patient’s clinical status worsened. The patient then underwent implantation of a left ventricular assist device. Congenital absence of the pericardium was confirmed at the time of surgery. This rare anomaly is due to abnormal formation of the pleuropericardial membrane. 1 Between 1982 and 1992, 10 patients who underwent echocardiography at the Mayo Clinic were found to have this anomaly. 2 Most patients are asymptomatic and rarely seek medical attention. A displaced precordial apical impulse that shifts medially when placing the patient in the left lateral decubitus position may be characteristic of the pericardial absence. 3 Congenital absence of the pericardium may be suspected when abnormal leftward rotation of the cardiac apex is detected on chest x-ray. 4 In our patient, however, this finding was masked by massive cardiomegaly. The echocardiographic features of congenital absence of the pericardium, in order of frequency, are (1) unusual echocardiographic windows, (2) cardiac hypermobility, (3) abnormal ventricular septal motion, and (4) abnormal swinging motion of the heart. 2

3. LA RA RV LV Figure 1. (Left) Parasternal long-axis view with unusual substernal, anterior displacement of the right atrium (RA). With pericardial absence, the entire heart is allowed to collapse into the left thorax due to the effects of gravity. Right ventricle (RV), left ventricle (LV), left atrium (LA). Still image. (Right) Click here for motion image.Click here for motion image

4. Figure 2. Coronal cardiac MR image demonstrating leftward displacement of all cardiac structures. The right atrium (RA) lies in an immediate substernal position, illustrating how the unusual parasternal long axis echo image (see Figure 1) was obtained. Still image. LA RA

5. References 1.Braunwald E, Zipes D, Libby, P. Heart Disease: A Textbook of Cardiovascular Medicine. 6 th ed. Philadelphia: W.B. Saunders Company, 2001. 2.Connolly HM, Click RL, Schattenberg TT, et al. Congenital absence of the pericardium: echocardiography as a diagnostic tool. J Am Soc Echocardiogr 1995;8:87-92. 3.Hermann H, Raizner AE, Chahine RA, Luchi RJ. Congenital absence of the left pericardium: an unusual palpation finding and echocardiographic demonstration of the defect. Southern Med J 1976;69:1222-5. 4.Raman SV, Daniels CF, Katz SE, Ryan JM, King MA. Congenital absence of the pericardium. Circulation 2001;104:1447.