**Losartan for Diffuse Myocardial Fibrosis in Sickle Cell Disease** This study is exploring if *losartan*, a medicine that blocks certain body chemicals, can help people with Sickle Cell Disease (SCD). SCD is a condition where red blood cells are shaped like a sickle, causing them to block blood flow. The study will last for 12 months and include 24 participants aged 6 and older. **Key Points:** - Study lasts **12 months**. - Participants will be checked without needing to sleep through the tests. - **24 patients** will be part of the study. Participants must have SCD and be on stable medicine for it. They should not be on regular blood transfusions or have heart issues. Pregnant individuals can't join, and those with certain health problems or on specific medications are excluded. The study aims to see if losartan is safe and effective in reducing certain heart issues in SCD patients.