Myotonic dystrophy (MyD) is a rare progressive multisystemic-inherited neuromuscular disease. It is often associated with cardiovascular disorders which require surgical procedures. However, it high sensitivity to anesthetic and neuromuscular blocking agents may result in respiratory complications. Myotonic dysorder due to hypothermia and conductive disorder following open-heart surgery are also risk-factor of perioperative management, thus open-heart surgery for MyD has rarely been reported. We describe the perioperative management for a MyD patient with an atrial septal defect (ASD) and mitral regurgitation (MR), who successfully underwent cardiac surgery. Minimally invasive cardiac surgery (MICS) with reverse-L-shaped partial sternotomy were useful method to minimize postoperative respiratory problems.