With the model heart’s double doors cracked
open, its network of ventricles and veins
exposed in the doctor’s palms

he walks us through circulation, pointing
out where my blood backflows and eddies
at the base of the aorta thanks to a stuttering valve.

Now we keep an eye on it, he says, placing the heart
back on its shelf. Later, we wait in the atrium
for an elevator. At least we know

you keep insisting. Better we know than not.
You stand at the water’s edge seeking my response
but I’m still treading that ultrasound’s

black river, bicuspid inheritance in stark white.
How strange now to feel the cadences

of this my plastic heart, one malformed
valve mawing like the mouth of a fish
caught and tossed on the shore.