For many White people, particularly those who live in White-centric communities, we never have to consider our own racial identity. I cannot tell you how many times Iâve heard White people called upon to describe their race only to have them say, âIâve never really thought about it. I guess Iâm just normal.â Hell, Iâm pretty sure I was talking this way not too long ago.
Sinus rhythm. A sinus rhythm is any cardiac rhythm where depolarisation of the cardiac muscle begins at the sinus node. It is characterised by the presence of correctly oriented P waves on the electrocardiogram (ECG). Sinus rhythm is necessary, but not sufficient, for normal electrical activity within the heart.
The normal heart rate is between 60 and 100 beats per minute. If the sinus node is without nerves (for example a transplanted heart) the heart rate is about 80 beats per minute. Two types of nerves regulate the heart rate. The sympathetic nerve speeds up the heart rate with exertion or excitement. The vagal nerves slow the heart rate.