This study will compare two treatments: pacemaker implantation and percutaneous transluminal septal ablation (PTSA) for patients with hypertrophic cardiomyopathy (HCM), a condition in which the heart muscle thickens and obstructs the flow of blood out of the heart. The reduced blood flow can cause chest pain, shortness of breath, palpitations, tiredness, lightheadedness and fainting.