At the end of the show when Dr. Kalu is comforting his patient, the patient reaches up with his right hand and rests it on the doctor's shoulder. Prominently shown is the fingertip monitor with the red LED light. During cuts back and forth between their faces, the monitor disappears and then reappears.
You can still die when you have a pacemaker implanted. A pacemaker only corrects the pace or rhythm of the heart muscle contractions. The only device capable of preventing death is an implantable defibrillator.