Case of a Blue, Painful Finger

endocarditisA 37-year-old female presented to the emergency department for evaluation of numbness and discoloration to her left fourth finger, which had started the day before. The patient stated that she was gardening the previous day and afterward she noticed the discoloration and pain. The patient denied taking any medications. She reported recreational methamphetamine and heroin use. She denied any chest pain or difficulty breathing. She denied any history of Raynaud’s phenomenon, venous thromboembolism, or history of trauma. The patient was afebrile with normal vital signs. Physical exam revealed cyanotic discoloration to the left distal fourth finger.  Sensation was intact to light touch and strength was 5 out of 5 in the finger. The capillary refill was diminished. Radial and ulnar pulses were 2+ bilaterally. Initially, a warm pack was placed to the patient’s finger with slight improvement, but without resolution of the pain and cyanosis. What is the diagnosis?