What does a rapid irregular pulse mean after a car accident?

Irregular heartbeat: If the heartbeat is irregular and not just fast, it is either what/s referred to as atrial fibrillation or supraventricular tachycardia. It's not unusual to have a rapid heartbeat after an accident as your body has a huge catecholamine output. It can be irregular for the same reason, but it should resolve. If the blood pressure is affected, it may require medical intervention.

Could be serious: Depending on the transfer of energy with the car crash, it is possible to have a cardiac contusion and associated heart arrhythmia. Okay to get evaluated; ekg and cardiac echo. With trauma the missed injury or the injury with a delay in presentation must be considered, especially if new symptoms develop.