US Patent 7226440 Method and device for accessing a pericardial space

A method for accessing a pericardial space of a heart of a mammalian patient is disclosed comprising: guiding a catheter through a coronary sinus of the heart and to a cardiac vein; advancing said catheter to a distal segment of the cardiac vein; intentionally puncturing the vein with the catheter to access the pericardial space, and performing a therapy or a diagnostic procedure using the catheter an the puncture in the vein and using the pericardial space.