Wearable and implantable monitoring devices are useful for tracking physiologic parameters like heart rate and rhythm and can easily share this information with doctors. Wearable devices like smartwatches and Holter monitors can record heart rhythms over extended periods. Implantable devices like the implantable loop recorder can be used for long-term monitoring without the need for charging or removal. They can detect infrequent arrhythmias and assess the efficacy of related treatment regimens. More invasive devices, like ventricular assist devices and total artificial hearts, are reserved for severely diseased patients. These innovative technologies extend beyond cardiology, transforming all fields of medicine.