Nairobi, Jan. 22 -- It's the carpentry of bones that intrigued him at the start. How someone could arrive with a broken limb and, through pulling, setting, casting, be walking again months later-the bone healed. The artistry of it is astonishing. The big-bone energy. "Orthopaedics felt like carpentry," says Dr Leonard Ngunga. "This idea of working with your hands."

So his first love wasn't the heart. It was bones. The heart came accidentally-sneakily, the way hearts often do. And once it arrived, it was relentless. It wanted what it wanted. And it wanted Ngunga.

Today, after years of training and experience, Dr Ngunga, a Consultant Interventional Cardiologist, serves as Head of Cardiac Care at Aga Khan University Hospital, while also le...