[Verse 1]
Follow the tide where the vena cava spills,
superior, inferior, two rivers off the hills,
into the right atrium, a dim and unlit room,
blood the color of midnight, hauling carbon's fume.
Tricuspid swings open, three flaps like a fan,
feeds the right ventricle, the engine's second hand,
pulmonic valve exhales it, sends it up and away,
through the pulmonary artery, the one vessel painted gray.
[Chorus]
Right side blue, left side true,
tricuspid, pulmonic, that's the right side's cue,
mitral, aortic, on the left we flow,
deoxygenated enters, oxygenated go.
Trace the loop, don't drop the thread,
blue goes out and comes back red,
four rooms, four doors, one steady beat,
structure by structure, the circuit's complete.
[Verse 2]
Lungs hand it back through four pulmonary veins,
oxygen riding shotgun, rinsing out the stains,
left atrium receives it, the calmest of the four,
mitral valve, two leaflets, closing like a bicuspid door.
Left ventricle flexes, the thickest wall in town,
built to shove a body's worth of pressure around,
aortic valve springs open, semilunar and precise,
out through the aorta — the artery of highest price.
[Verse 3]
Now follow the spark, not the crimson tide,
sinoatrial node, the pacemaker, sits high on the right side,
sixty to a hundred, it's whispering the beat,
down to the AV node, taking a purposeful retreat,
a pause that lets the atria empty out their share,
then the Bundle of His splits — a left lane and a right,
Purkinje fibers scatter like roots beneath the floor,
squeezing ventricles skyward, that's the systole roar.
Septum stands the border between the blue and red,
coronary arteries crown the muscle, keep it fed,
pericardium's the coat, myocardium's the might,
endocardium's the lining, smooth and satin-tight.
[Bridge]
This isn't memorized, it's mapped and understood,
connection to connection, the way the current should —
chamber feeds a valve, a valve feeds an artery's line,
learn the wiring once and the whole thing stays online.
[Verse 4]
Every heartbeat's a lesson, a loop you can retrace,
map the chambers, valves, and vessels, give the current its place,
from vena cava's whisper to aorta's mighty shout,
the body's story circulates, and never runs out,
diastole fills the chambers, systole sends the wave,
this rhythm keeps repeating from the cradle to the grave.
[Chorus]
Right side blue, left side true,
tricuspid, pulmonic, that's the right side's cue,
mitral, aortic, on the left we flow,
deoxygenated enters, oxygenated go.
Trace the loop, don't drop the thread,
blue goes out and comes back red,
four rooms, four doors, one steady beat,
structure by structure, the circuit's complete.
[Outro]
Sinoatrial whispers, the Bundle carries on,
vena cava to aorta, gone before the dawn —
say it slow, structure by structure, till the whole map wakes.