She was taken to a hospital suffering from an irregular heartbeat.

她因心律不齐而被送进医院。

《柯林斯英汉双解大词典》

Symptoms: Tiredness, lethargy, irregular heartbeat.

症状：疲劳、昏睡、心跳不规律。

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Anemia can lead to a rapid or irregular heartbeat - an arrhythmia.Your heart must pump more blood to compensate for the lack of oxygen in the blood when you're anemic.

贫血会导致心律失常——这是因为贫血时血液的供氧能力下降，作为代偿心脏不得不燃烧小宇宙，在单位时间内泵出更多的血，从而使心跳变快，或不规则。

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An irregular heartbeat, known as atrial fibrillation, can also lead to ischaemic stroke.

BBC: Andrew Marr: Why do healthy people have strokes?

Best has been diagnosed with an irregular heartbeat but has now been given the all-clear by doctors in Bordeaux.

BBC: McCall slams Ulster performance

Cardiac ablation therapy to control an irregular heartbeat will no longer be available to most patients at the hospital.

BBC: NEWS | UK | England | Oxfordshire | Trust could axe 600 health posts