A 35-year-old, gravida (G2,P0) patient with a history of hypothyroidism presented at 26 weeks’ gestation with progressive exertional dyspnea and fatigue of several weeks duration. She also reported several recent syncopal episodes. Her first pregnancy was uncomplicated, and she denied prior cardiopulmonary disease, illicit drug use, or ingestion of anorexigens. On physical examination, her vital signs were as follows: BP, 90/60 mm Hg; heart rate, 105 beats/min; respiratory rate, 20 breaths/min; and oxygen saturation as measured by pulse oximetry, 92%. Jugular venous distension was present. Cardiac auscultation revealed a loud S2 and a grade 3/6 systolic murmur over the left lower sternal border that was accentuated on inspiration. Lung fields were clear to auscultation bilaterally. Extremities were without clubbing, and 1+ edema was present. An ECG was interpreted as representing normal sinus rhythm. A chest radiograph was unremarkable for parenchymal infiltrates, and a ventilation-perfusion scan was interpreted as revealing a low probability for a pulmonary embolism. Arterial blood gas measurements revealed the following: pH, 7.45; PCO2, 29 mm Hg; PO2, 79 mm Hg; and bicarbonate level, 20 mEq/L. An echocardiogram displayed a dilated right ventricle, paradoxical septal wall motion, and normal left ventricular wall motion.
The patient was admitted to labor and delivery and was prescribed bed rest, oxygen, diuretics, and heparin. Fetal heart tones were noted at 150 beats/min, and IM corticosteroids were administered to accelerate fetal lung development. Despite this therapy, the patient continued to report progressive dyspnea, and at 32 weeks’ gestation the placement of a pulmonary artery catheter (PAC) demonstrated moderate pulmonary hypertension. IV epoprostenol therapy was initiated at 4 ng/kg/min, producing an improvement in the hemodynamic profile. At 36 weeks’ gestation, while receiving IV epoprostenol, the premature rupture of membranes occurred followed by active labor. However, the progression of labor was inadequate, and a cesarean section was scheduled. Preoperatively, a PAC was placed and epidural anesthesia was administered. Subsequently, the cardiac output declined from 7.4 to 4.1 L/min and the epoprostenol infusion was increased to 10 ng/kg/min. The patient remained hemodynamically stable throughout the cesarean section and delivered a healthy male infant weighing 7 lbs with Apgar scores of 5 and 9, respectively, at 1 and 5 min. A bilateral tubal ligation was performed with patient consent. Following extubation, the PAC was maintained for 48 h to assist with IV fluid administration, and the hemodynamic profile remained stable with the patient receiving 10 ng/kg/min epoprostenol. On postoperative day 2, heparin therapy was resumed.
Three weeks later, the patient underwent a vasodilator trial with calcium-channel blockers but did not have a favorable response, hence, she was continued on epoprostenol therapy. Presently, she has resumed an active lifestyle as a housewife and mother. Furthermore, her 2-year-old son is in good health without any developmental delays.