Carney complex (CNC) is a familial multiple neoplasia syndrome characterized by cardiac and extracardiac myxomas in the setting of spotty skin pigmentation and endocrinopathy. We previously identified PRKAR1A (regulatory subunit 1α of protein kinase A) mutations in CNC. Mutational analyses of the PRKAR1A gene in 51 unrelated CNC probands now detect mutations in 65%. All mutations, except for one unique missense mutation, lead to PRKAR1A haploinsufficiency. Therefore, we studied the consequences of prkar1a haploinsufficiency in mice. Although we did not observe cardiac myxomas or altered pigmentation in prkar1a +/– mice, we did observe some phenotypes similar to CNC, including altered heart rate variability. Moreover, prkar1a +/– mice exhibited a marked propensity for extracardiac tumorigenesis. They developed sarcomas and hepatocellular carcinomas. Sarcomas were frequently associated with myxomatous differentiation. Tumors from prkar1a +/– mice did not exhibit prkar1a loss of heterozygosity. Thus, we conclude that although PRKAR1A haploinsufficiency does predispose to tumorigenesis, distinct secondary genetic events are required for tumor formation.

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Thromboembolic disease accounts for thousands of hospitalizations every year in the US. Its primary management consists of anticoagulation. However, in certain instances this may be contraindicated or not sufficient. Mechanic occlusion of the inferior vena cava (IVC) becomes then a viable alternative. In this case a 35-year-old man presented with a saddle pulmonary embolus but was unable to be anticoagulated due to intestinal bleed. A removable IVC filter was then placed. The filter spontaneously migrated into the right atrium causing severe tricuspid regurgitation, perforation of the atrial wall, and cardiac tamponade. The device was successfully retrieved percutaneously and the patient discharged from the hospital in stable condition. This case illustrates the potentially lethal complications associated with the use of IVC filters, as well as the possibility to percutaneously recover them from within the right atrium.

Shortly after Kono and associates 1 reported their findings concerning the role of vascular endothelial growth factor (VEGF) gene expression in the development of cardiac myxomas, we had the opportunity to assay plasma VEGF before and after surgery in a 31-year-old black woman with multicentric recurring myxomas. At the age of 10 years, she had undergone excision of a left atrial myxoma. In the following decade, she had 4 more operations with excision of 19 myxomas. The tumors (9 on the right side and 10 on the left side), occurring at widely separated and random sites within both atria and on the tricuspid and mitral valves, appeared to develop de novo without invasion of surrounding tissue. The sizes ranged from a "nodule" to 3 × 4 cm, and the histologic features, by both light and electron microscopy, were typical for myxoma. Now, 12 years after her fifth heart operation, the tumor recurred and she underwent a sixth operation. We report our observations. MethodsThree tumors were resected. The largest (7.0 × 4.9 × 1.2 cm) arose from the floor of the right atrium between the inferior vena cava From the Division of Cardiovascular Diseases,