Kirsten is a congenital cardiac surgeon trained in New Zealand and the UK and leading the Greenlane and then the Starship congenital cardiac surgical unit from 1996 until her recent retirement in March 2024. During this career there has been a focus on providing cardiac surgery to those in less well developed countries. From 2014 Kirsten and a surgical team worked together to travel to Fiji for a yearly visit to operate on children with simple cardiac defects. In 2023 the team operated in the Suva Sanjeevani hospital, built with charitable funds, and are now planning ongoing visits with the support of the Pacific Medical Association Group and staff from Starship Hospital, to do children from all over the south Pacific.