A 57-year-old woman presents to her primary
care physician complaining of shortness of
breath. These symptoms first began after strenuous exercise approximately 6 months ago, but
over the past month she has felt short of breath
after climbing 10 steps and sometimes at rest.
She has no known medical problems, but has
not seen a physician in 5 years. She is not taking any medication and is a nonsmoker. Cardiac examination is notable for a loud P2 component of S2 but no murmurs. Her fingers are
shiny, swollen, and indurated. She also has several telangiectasias on her hands and hard,
subcutaneous nodules on her finger pads. Laboratory evaluation is significant for elevated an ticentromere antibody but normal antitopoisomerase I antibody. What is the most likely diagnosis in this patient?