The video talks about the difference between one lead, two leads and three leads pacemakers by Dr. Aparna Jaswal, Cardiologist, Fortis Escorts Heart Institute. Pacemakers are generally are implanted in the right atrium and right ventricle. A bi-ventricular pacemaker has one lead in the right atrium and tow leads in both the ventricles. She will also talk about lead-less pacemakers which are a recent technology and are US FDA approved and have a battery life of 9 – 12 years.