The "Heart Monitor" is a feature that was scrapped from Metroid Fusion. It was represented as a small electrocardiographic circle on the screen that would vibrate whenever X Parasites were nearby. Why it was scrapped is unknown.
Since it seemingly tracks X, it is similar to the motion tracker used to detect the Xenomorph creatures of the Alien films which inspired Metroid.
| Targeting Reticule | Threat Assessment | Radar | Map | Energy Meter | Phazon level | "Heart Monitor"|
Translator Module | Screen-Shot Tool | Sight Window | Scan Point | Infrared Ray Scope
Charge Meter | Missile Counter | Ammo Gauge | Visor Select | Command Icon