A 35-year-old female with a 10-year history of rheumatic arthritis presents with 4 years of palpitations and shortness of breath on exertion, recently worsened and unable to lie flat at night. Physical exam reveals: diastolic rumbling murmur at the apex, fine crackles heard at the lung bases, abdominal distension, and bilateral lower extremity edema. The type of heart failure in this patient is: