LAUSR

Background: A 35-year-old G1P1 woman with a history of bioprosthetic mitral valve (MVR) and aortic valve (AVR) replacements and a tricuspid valve annuloplasty for presumed rheumatic heart disease who presented at 35 weeks gestational age with COVID-19 ARDS and shock. Case: The patient arrived with ARDS requiring intubation and distributive shock. Transthoracic echocardiogram (TTE) revealed a small left ventricular (LV) cavity with LV hypertrophy, MVR with mean gradient of 14 mmHg, and a mid-peaking transaortic gradient of 96 mmHg consistent with fixed obstruction. This gradient was likely due to LV outflow tract obstruction (LVOTO) from the combination of a small LV cavity and septal angulation of the MVR struts rather than AVR dysfunction. The patient underwent emergent cesarean section. Decision-making: The maternal and fetal risks of ARDS and distributive shock were primary considerations in undergoing cesarean section. Decisions regarding management thereafter were driven by three elements of her clinical presentation - anticipated peripartum hemodynamic shifts, multivalvular disease, and ARDS. The increased plasma volume from postpartum autotransfusion risked worsening her ARDS but also potentially benefited the LVOTO through increased preload. The effect of lower postpartum cardiac output and heart rate on valvular obstruction in series also had to be considered. To balance these hemodynamic demands, after delivery, her vasopressors were switched from norepinephrine to phenylephrine, and she was judiciously diuresed. A postpartum TTE demonstrated improved transmitral gradients (mean 5 mmHg) but ongoing LVOTO. Higher filling pressures than otherwise ideal in ARDS were tolerated given persistent gradients. She was liberated from hemodynamic and ventilator support and transferred out of ICU care. Though she died of infectious complications weeks later, close collaboration between the critical care, obstetrical, and cardiovascular teams were essential to her care. Conclusion: Care of the peripartum patient with cardiovascular disease, especially valvular disease, must take into consideration both their cardiac pathology and expected peripartum hemodynamic shifts.