lung embolismsubsegmental pulmonary embolismmultiple pulmonary embolismspulmonary embolism diagnosissubmassive pulmonary embolismpulmonary embolism prognosispulmonary embolism pregnancypulmonary embolism postpartummassive pulmonary embolismchronic pulmonary embolismbilateral pulmonary embolismsegmental pulmonary embolism