Patients with heart problems sometimes experience issues with regulating their heart beat and often require artificial pacemakers. but the problem with artificial pacemakers is that they aren't that great anymore and have to be checked and replaced periodically. A review article published on November 20 in Trends in Molecular Medicine highlights the promise and limitations of new methods based on stem cell and reprogramming technologies to generate biological pacemakers that might one day replace electronic pacemakers. Biological pacemakers, which are composed of electrically active cells, can functionally integrate with the heart and could provide natural heart rhythm regulation without the need for indwelling hardware. One way to work with stem cells; scientists can coax the stem cells into becoming cells found in the SAN (Sino-Atrial Node). The second way to work with stem cells; by directly programming supporting cells, already present in the heart - for example, fibroblas