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. Alternatively, it could have been a decibel meter that would measure the amount of noise Samus was making; such a feature would be used many years later in The Legend of Zelda: Breath of the Wild.
|Targeting Reticule | Threat Assessment | Radar | Map | Energy Meter | Phazon level | "Heart Monitor"|
Translator Module | Screen-Shot Tool | "Low battery warning" Sight Window | Scan Point | Infrared Ray Scope
Charge Meter | Missile Counter | Ammo Gauge | Visor Select | Command Icon | Hover Gauge | Aeion Gauge | Bookmark/Map Pin | Nav point | Points bonus