Abstract 11095: Abdominal Paraganglioma: A Rare but Non-Negligible Etiology of Severe Dyspnea in Late Gestation

With a history of cesarean delivery of a dead baby at 36 weeks of pregnancy due to severe dyspnea two years ago, a 25-year-old woman with 32 weeks of pregnancy complained severe dyspnea again and was transferred to our emergency department. Her serum test showed extremely elevated NT-proBNP. Her echocardiography exhibited normal left ventricular ejection fraction (LVEF) but diffused myocardial hypertrophy/edema, resulting in decreased inner diameters in the left ventricle and left atrium, which is quite different from other diastolic heart dysfunctions usually showing an enlarged left atrium. After emergency cesarean delivery, her cardiac walls became thinner, and the left ventricle and atrium inner diameters increased correspondingly on echocardiography along with the relieved dyspnea, but the baby did not survive either. The prominent elevation in serum norepinephrine as well as the abdominal vascular ultrasound indicated the probability of a paraganglioma below the abdominal aorta bifurcation, which was finally confirmed by pathology. However, whole exome sequencing did not exhibit the usual gene mutation reported but exhibited the RYR2 heterozygous mutation in c.2642T>G, which was likely pathogenic according to bioinformatic analysis. Therefore, the severe dyspnea in her late gestation was due to the occupancy of the enlarged uterus on the paraganglioma below the abdominal aorta bifurcation, thus inducing considerable catecholamine excretion and the incidence of catecholamine cardiomyopathy (Takotsubo syndrome). To the best of our knowledge, this is the first report showing the special location of a paraganglioma exacerbated by pregnancy. The adverse pregnancy outcome emphasized the importance of the early diagnosis of paraganglioma-induced cardiomyopathy, which is rare and easily neglected by clinical obstetricians. Our case implicates that for pregnant patients with diastolic dysfunction who are contraindicated for cardiac MRI, the diffused myocardial hypertrophy/edema, especially the decreased left atrium inner diameter displayed in echocardiography, could suggest the incidence of paraganglioma-induced cardiomyopathy rather than other diastolic heart dysfunctions, such as hypertensive heart failure of pregnancy.