My Husband Has Just Been Told That His Triglyceride Level

My husband has just been told that his triglyceride level is at 1000! Determined by analysis of fluid taken out of his lung. He had the aorta valve replacement last September through the tavor method. Had a lung biopsy in May - no cancer but inflammation in the lower lobe of one lung. What should he be doing to lower triglyceride level?