Case Background

Our patient is a 37-year-old woman with a chief complaint of shortness of breath and intermittent palpitations of three months duration.

The pertinent features of her history include the following: at the age of twelve she had a febrile illness associated with painful joints that resolved with bed rest and aspirin therapy. During the third trimester of her only pregnancy at the age of thirty, she developed nocturnal dyspnea that was treated with diuretics. Her symptoms completely resolved after delivery and a follow-up chest X ray was normal. One year ago she developed progressive fatigue and dyspnea on exertion.

In spite of therapy with diuretics, three months ago she again developed paroxysmal nocturnal dyspnea with 2-pillow orthopnea, intermittent palpitations, and ankle swelling.
There is no history of a murmur heard during childhood, chest pain, cyanosis, syncope, or cerebrovascular events.

Choose the best diagnosis based on the history in our patient: