Pacemakers and pacemaker electrodes

An electrode line for a pacemaker, the electrode line comprising a lead having an end and an electrode electrically connected to the end of the lead, the electrode comprising:

• a carbon nanotube composite structure comprising a matrix and at least one carbon nanotube structure located in the matrix;
• wherein the matrix comprises a first surface and a second surface opposite to the first surface, the at least one carbon nanotube structure comprises a first end and a second end opposite to the first end, the first end of the at least one carbon nanotube structure protrudes out of the first surface of the matrix, and the second end of the at least one carbon nanotube structure protrudes out of the second surface of the matrix and is electrically connected to the end of the lead.