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  2. Heart rate variability - Wikipedia

    en.wikipedia.org/wiki/Heart_rate_variability

    Heart rate variability (HRV) is the physiological phenomenon of variation in the time interval between heartbeats. It is measured by the variation in the beat-to-beat interval. Other terms used include "cycle length variability", "R–R variability" (where R is a point corresponding to the peak of the QRS complex of the ECG wave; and R–R is ...

  3. Bradycardia - Wikipedia

    en.wikipedia.org/wiki/Bradycardia

    Bradycardia, also called bradyarrhythmia, is a resting heart rate under 60 beats per minute (BPM). [1] While bradycardia can result from various pathologic processes, it is commonly a physiologic response to cardiovascular conditioning or due to asymptomatic type 1 atrioventricular block. Resting heart rates of less than 50 BPM are often normal ...

  4. Heart rate - Wikipedia

    en.wikipedia.org/wiki/Heart_rate

    The American Heart Association states the normal resting adult human heart rate is 60–100 bpm. An ultra-trained athlete would have a resting heart rate of 37–38 bpm. [3] Tachycardia is a high heart rate, defined as above 100 bpm at rest. [4] Bradycardia is a low heart rate, defined as below 60 bpm at rest.

  5. Cardiac conduction system - Wikipedia

    en.wikipedia.org/wiki/Cardiac_conduction_system

    A slow heart rate of 60 or less beats per minute is defined as bradycardia. A fast heart rate of more than 100 beats per minute is defined as tachycardia. An arrythmia is defined as one that is not physiological such as the lowered heart rate that a trained athlete may naturally have developed; the resting heart rates may be less than 60 bpm.

  6. What You Need to Know About Abnormal Heart Rhythm - AOL

    www.aol.com/know-abnormal-heart-rhythm-145227534...

    Types of Abnormal Heart Rhythms Tachycardia. Tachycardia is a heart rate that's too fast—a resting heart rate of over 100 BPM. The normal range for heart rates is between 60 and 100 BPM. When ...

  7. Cardiac pacemaker - Wikipedia

    en.wikipedia.org/wiki/Cardiac_pacemaker

    The rate at which these impulses fire controls the rate of cardiac contraction, that is, the heart rate. The cells that create these rhythmic impulses, setting the pace for blood pumping, are called pacemaker cells, and they directly control the heart rate. They make up the cardiac pacemaker, that is, the natural pacemaker of the heart.

  8. Cardiac physiology - Wikipedia

    en.wikipedia.org/wiki/Cardiac_physiology

    The resting heart rate of a newborn can be 120 beats per minute (bpm) and this gradually decreases until maturity and then gradually increases again with age. The adult resting heart rate ranges from 60 to 100 bpm. Exercise and fitness levels, age and basal metabolic rate can all affect the heart rate. An athlete's heart rate can be lower than ...

  9. Cardiac output - Wikipedia

    en.wikipedia.org/wiki/Cardiac_output

    Major factors influencing cardiac output – heart rate and stroke volume, both of which are variable. [1]In cardiac physiology, cardiac output (CO), also known as heart output and often denoted by the symbols , ˙, or ˙, [2] is the volumetric flow rate of the heart's pumping output: that is, the volume of blood being pumped by a single ventricle of the heart, per unit time (usually measured ...