Lost Life ~Dakedo Kimi ni Tsutaetai Koto~

Main character is a doctor with a congenital heart disease, so he can die at any time. He wants to live on, but it's selfish to involve anyone in his life. The life without loving anyone or grieving anyone...
But there are girls around him who wish to make his life positive. They support him and share their warmth with him.

[From vndbreview]