Dr. Mack has been intimately involved in research throughout his career. During his training he spent two years in the Cardiothoracic Surgery Research Laboratory. His work at this time focused on alternative treatments for patients with coronary artery disease. In collaboration with Dr. Ronald Crystal, this work focused on gene therapy for myocardial angiogenesis and transmyocardial laser revascularization. Results of this preclinical work laid the foundation for the first human heart gene therapy trials. During this time, Dr. Mack was awarded the Merle Wood Scholar Research Award of the Morrow Society. In addition, he developed and patented a gene transfer device for the purpose of direct myocardial gene transfer. More recently his primary interest has been the surgical treatment of atrial fibrillation (Maze Procedure). In addition to maintaining a large database of patients who have undergone Maze procedures in conjunction with concomitant cardiac procedures, he is actively involved in further developing cryothermy ablation technology. Dr. Mack developed a "cryoclamp device" that can be used on the beating heart in patients with atrial fibrillation. He is currently actively involved in optimizing a minimally invasive surgical approach to treat patients with atrial fibrillation. In addition, to his work in atrial fibrillation, Dr. Mack is also interested in other areas of ongoing research including the development of percutaneous valve technology and heart failure. His many publications in multiple areas of cardiothoracic surgery and gene therapy have been presented at various national meetings.