wave

[wāv]

1. a uniformly advancing disturbance in which the parts undergo a change in direction, such as a progressing disturbance on the surface of a liquid.

2. variation in the transmission of electromagnetic energy, especially the periodic change in direction of a reading on a monitoring device.

A wave the wave on a His bundle electrogram that represents atrial activation.

alpha w's brain waves having a frequency of 8 to 13 per second, typical of a normal person awake in a quiet resting state; they occur primarily in the occipital region.

B wave a sharp rhythmic oscillation with a sawtooth pattern, occurring every 30 seconds to two minutes during intracranial pressure monitoring, associated with unstable increases in pressure.

beta w's brain waves having a frequency of 18 to 30 per second, typical during periods of intense central nervous system activity; they occur primarily in the parietal and frontal regions.

brain w's changes in electric potential of different areas of the brain, as recorded by electroencephalography. See also alpha, beta, delta, and theta waves.

C wave in intracranial pressure monitoring, a small rhythmic oscillation in pressure that occurs every four to eight minutes.

delta w's

1. brain waves having a frequency below 3½ per second, typical in deep sleep, in infancy, and in serious brain disorders.

2. an early QRS vector in the electrocardium in wolff-parkinson-white syndrome.

dicrotic wave the second portion of the tracing of a sphygmograph of the arterial pulse or arterial pressure after the dicrotic notch, attributed to the reflected impulse of closure of the aortic valves. Called also recoil wave

electromagnetic w's the entire series of ethereal waves, which are similar in character and move at the speed of light but vary enormously in wavelength. The unbroken series is known from radio waves that may be many kilometers in length through light waves, ultraviolet rays, x-rays, and gamma rays, to the cosmic rays, whose wavelength may be as short as 40 femtometers (4 × 10⁻¹⁴ m).

light w's the electromagnetic waves that produce sensations on the retina; see also vision.

P wave a positive deflection in the normal surface electrocardiogram produced by the wave of excitation passing over the atria; it represents atrial depolarization, an intrinsic atrial event.

papillary wave (percussion wave) the chief ascending portion of the tracing of a sphygmograph.

plateau wave a wave seen during intracranial pressure monitoring in advanced stages of increased pressure, signaling hypoxia of the brain cells.

pulse wave the elevation of the pulse felt by the finger or shown graphically in a recording of pulse pressure.

Q wave in the QRS complex, the initial electrocardiographic downward (negative) deflection, related to the initial phase of depolarization.

QRS wave QRS complex.

R wave in the normal surface electrocardiogram, the initial upward deflection of the QRS complex, following the Q wave; it represents ventricular depolarization. In cardiac pacing, it may be the entire native or intrinsic QRS complex.

radio w's electromagnetic waves of wavelength between 10⁻¹ and 10⁶ cm and frequency of about 10¹¹ to 10⁴ hertz.

recoil wave dicrotic wave.

S wave a downward deflection of the QRS complex following the R wave in the normal surface electrocardiogram.

sonic w's audible sound waves.

sound w's longitudinal waves of mechanical energy that transmit the vibrations interpreted as sound (def. 2).

T wave the second major deflection of the normal surface electrocardiogram, reflecting the potential variations occurring with repolarization of the ventricles.

theta w's brain waves having a frequency of 4 to 7 per second, occurring mainly in children but also seen in adults under emotional stress.

tidal wave the wave after the percussion wave on a sphygmograph recording; the second elevation of the tracing, preceding the dicrotic wave.

ultrasonic w's waves similar to sonic waves but of such high frequency (20,000 hertz or higher) that the human ear does not perceive them as sound; see ultrasonics.

S wave

a negative (downward) deflection of the QRS complex following an R w; successive downward deflections within the same QRS complex are labeled S', S'', etc.

shear wave

A seismic body wave that shakes the ground perpendicularly to the direction in which the wave is moving.

S wave

(wāv)

A component of the cardiac cycle seen on electrocardiography as a negative (downward) deflection of the QRS complex following an R wave; successive downward deflections within the same QRS complex are labeled S', S'', and so on.

Patient discussion about S wave

Q. What kind of depression is characterized by waves? It's not a constant depression, like if you can be happy but then you feel the depression creeping up on you, like a wave, lasts for a few to several days/weeks? Is there even a name for it?

A. Depression doesn't have to be a constant 24/7 nightmare. You can smile and laugh all day but by the evening be miserable. Its still depression. There are however different labels with depression. There is acute depression (lasting less than two weeks) there is Major Depression (lasting more than two weeks) and there is chronic (lasting a LONG time). People all have different levels of severity and different expressions of it. Some people stop eating and can't leave their bed, others have a smile on there face and seem fine at work, all while they are being torn apart on the inside. As far as diagnosis and treatment goes: if depression is disturbing your life, if you have been experiencing symptoms including loss of interest everyday (not necessarily ALL day) for more than two weeks, you are depressed and deserve treatment.

(Bipolar is actually a very different thing and treated very differently than depression.)

More discussions about S wave

This content is provided by iMedix and is subject to iMedix Terms. The Questions and Answers are not endorsed or recommended and are made available by patients, not doctors.