Which group of rhythms is considered immediately life-threatening and requires the technician to summon help right away?

Giải thích

Ventricular fibrillation, pulseless ventricular tachycardia, and asystole produce no effective cardiac output, so survival depends on immediate recognition and activation of the emergency response. The sinus rhythms in the first choice are common and often benign. First-degree block, flutter, and premature atrial beats need reporting but not emergency action, and junctional or paced rhythms usually maintain perfusion.