[Verse 1]
Forget the number on the old worn chart,
Anderson says look closer, read the septum like a map,
Three coordinates, not just one,
borders, geography, and where the great vessels run.
Is the rim stitched with fibrous thread,
valve continuity holding the margin's edge,
or is it muscle all the way round,
a closed horizon with no fibrous ground?
[Chorus]
Borders, position, and the valves up top,
three clues to limn every gap you've got,
Perimembranous, muscular, doubly committed too,
sing the crosswalk till the old names come through,
Type one, two, three — watch them fall in line,
Anderson's compass, reading the septal design.
[Verse 2]
Perimembranous hugs the fibrous trigone,
tricuspid and aortic touching, never alone,
it opens toward the inlet, the trabecular floor,
sometimes the outlet too — it's a doorway, not a wall.
Muscular defects, they wander and hide,
apical, mid, or marginal, muscle on every side,
no valve tissue lining their rim,
a closed muscular ring, self-contained within.
[Chorus]
Borders, position, and the valves up top,
three clues to limn every gap you've got,
Perimembranous, muscular, doubly committed too,
sing the crosswalk till the old names come through,
Type one, two, three — watch them fall in line,
Anderson's compass, reading the septal design.
[Verse 3]
Now the doubly committed, juxta-arterial kind,
sits just below where pulmonary and aortic valves align,
no muscle bar dividing the two,
a confluence of great vessels sharing one view,
the outlet septum's practically gone,
so the ventricle's crest can't carry on,
this is the defect the textbooks call its own,
subarterial, supracristal — same tale, different tone.
[Bridge]
Perimembranous meets inlet, trabecular, outlet too,
Roman numerals fading as the picture comes through,
Kirklin's numbers, Soto's rings, all converge right here,
three simple coordinates make the whole map clear.
[Verse 4]
So when the echo shows a hole in the wall,
don't just measure millimeters, don't just recall a number at all,
ask what borders it, ask where it lies,
ask which great vessels are peering down from above,
that's the language the surgeons and the anatomists share,
a rim, a route, a roof — that's how you get there.
[Chorus]
Borders, position, and the valves up top,
three clues to limn every gap you've got,
Perimembranous, muscular, doubly committed too,
sing the crosswalk till the old names come through,
Type one, two, three — watch them fall in line,
Anderson's compass, reading the septal design.
[Outro]
Borders, position, the valves overhead,
three coordinates instead of a number in your head,
Perimembranous, muscular, doubly committed call,
Anderson's compass maps the septal wall.