Is pectus excavatum going to affect my heart over time?

If severe. In severe pectus deformity, pediatric patients experience excersise intolerance, lack of stamina because of dyspnea, sometimes chest pains, mitral valve prolapse, experience palpitations and recurrent respiratory tract disease. Therefore if the pectus deformity is so mild that did not get repaired early in life, chances of cardiac problems are less.