Case 2 68-year-old Mr. Quincy is complaining of left leg swelling for the past 2

Case 2
68-year-old Mr. Quincy is complaining of left leg swelling for the past 2 weeks. The swelling started while he was on a cruise. The swelling is intermittent and below the knee to his foot. He describes a cramplike pain in his left calf. Lately, both legs have been cramping while walking, but it resolves when he sits. He denies any fever, warmth, erythema, or trauma. 
Past medical history: iliofemoral deep vein thrombosis of his left leg after he had left hip replacement for osteoarthritis 9 months ago; treated with rivaroxaban for 6 months; stable angina; obesity (BMI 31); dyslipidemia. 
Social history: quit smoking 4 years ago but resumed one-fourth pack per day 1 year ago. 
Medications: simvastatin; aspirin; metoprolol.
Note: Assume history and examination is within normal limits if not listed. 
Physical examination: vital signs are within normal limits; right leg is within normal limits except hairless, shiny skin; left leg has 1+ pitting edema in the pretibial area and foot; mild pain with left calf compression and one small tortuous vein on the medial aspect of his calf; left leg is also hairless and shiny. A venous duplex Doppler ultrasound of his left leg was done and reveals no deep vein thrombosis. 
Activity
Identify the probable diagnosis and what data support your decision.  
Describe the pathogenesis for the diagnosis. 
What data are inconsistent with your diagnosis?  
What diagnostic tests would you order, if any, and how would you treat this patient?