A premature atrial contraction (PAC) occurs when a focus in the atrium (not the SA node), generates an action potential before the next scheduled SA node action potential. When this occurs prior to ...

A premature ventricular contraction occurs when a focus in the ventricle generates an action potential before the next scheduled sinoatrial nodal action potential. Premature, occurring earlier than ...

Sometime during your second or third trimester, you might start to feel mild, sporadic contractions, especially when you are tired or dehydrated, or after sex. These normal contractions, called ...

Peng Du is a co-founder and has shares in Alimetry Ltd. He receives funding from Royal Society Te Apārangi and the US National Institute of Health. peikai.zhang@auckland.ac.nz is affiliated with The ...