In an implantable sensor lead for sensing mechanical cardiac activity of a heart, as well as a sensing method and a cardiac stimulator embodying such a sensor lead, multiple cardiac activity sensing elements are distributed along a portion of a length of the lead body of the implantable lead. The sensing elements sense or detect mechanical cardiac activity and respectively emit electrical signals corresponding to the detected mechanical cardiac activity. The delivery of cardiac stimulation pulses can be controlled dependent on an analysis of the detected mechanical cardiac activity.