A pericardiocentesis apparatus and method for accessing the pericardial space. The invention consists of inserting a percutaneous tube whose tip has a hole which is positioned over and contacts the anterior pericardium. Introducing a vacuum within the tube forms a pericardial bleb within that hole. A guided needle within the tube is advanced to puncture the pericardial bleb while avoiding contact with the epicardium. A hollow filament or electrocardial lead or flexible guide wire within the needle can then be advanced into said pericardial cavity. The guide wire may be used to guide a intrapericardial catheter into the pericardial space for injection or infusion of selected therapeutic agents into the pericardial space to treat various heart and blood vessel diseases. Controlled drug release material(s) can be injected through the needle for the slow and/or sustained delivery of the therapeutic agents into the pericardial cavity.