>> WE HAD EXPERIENCED
TWO MISCARRIAGES PRIOR
TO BECOMING PREGNANT
WITH GRACE.
SO ONCE WE MADE IT THROUGH
THAT 12TH, 13TH WEEK
OF THE PREGNANCY,
WE KIND OF FELT LIKE,
OK, THINGS ARE GREAT.
>> WE'RE BEYOND
THAT--THAT HUMP,
THAT HURDLE WE HADN'T CLEARED
WITH TWO MISCARRIAGES,
AND NOW HERE IT WAS,
LIKE, GREAT, YOU KNOW.
>> THINGS ARE LOOKING UP.
>> YEAH, CLEAR
SAILING FROM HERE ON OUT.
>> SO THEN WE APPROACHED
THE 20-WEEK ANATOMY SCAN
AND WENT TO THE
DOCTOR'S OFFICE.
AND I COULD TELL THAT THE
TECHNICIAN WAS STICKING ON
THE HEART FOR A VERY
LONG PERIOD OF TIME.
AND SHE LEFT THE ROOM
AND BROUGHT IN OUR
MATERNAL/FETAL
MEDICINE DOCTOR.
AND SHE SAID, YOU KNOW,
"YOUR BABY HAS A CONGENITAL
HEART DEFECT, AND IT'S
REFERRED TO AS TRANSPOSITION
OF THE GREAT ARTERIES."
>> ALL OF HEART
SURGERY IS 50 YEARS OLD,
AND WE'VE COME FROM
A SITUATION OF BEING ABLE
TO TREAT NOTHING TO BEING ABLE
TO AT LEAST DEAL WITH MOST,
IF NOT THE VAST MAJORITY OF,
CONGENITAL HEART DEFECTS
IN A WAY THAT ALLOWS CHILDREN
TO GROW INTO ADULTHOOD.
>> WE LIVE IN AN ERA WHERE
THERE ARE VERY FEW THINGS
THAT WE REALLY CAN'T
TAKE CARE OF WITH EXCELLENT
OUTCOME AFTER BIRTH.
>> ONLY TIME WILL TELL WHAT THE
LONG-TERM OUTCOME REALLY IS.
>> AND AS WE FOLLOW
THEM FORWARD IN TIME,
THERE MAY BE NEW THINGS
THAT WE'LL LEARN ABOUT THEM.
BUT THE GOOD NEWS IS THAT
THE VAST MAJORITY OF THESE
PATIENTS PERFORM EXCELLENTLY
AND GO ON TO LEAD HAPPY,
HEALTHY LIVES.
>> TRANSPOSITION OF THE
GREAT ARTERIES IS A COMPLEX
CONGENITAL HEART LESION
WHERE THE TWO GREAT VESSELS
THAT COME OUT OF
THE HEART, THE AORTA,
WHICH TAKES BLOOD FROM THE
LEFT VENTRICLE TO THE REST
OF THE BODY, AND
THE PULMONARY ARTERY,
WHICH COMES OFF THE RIGHT
VENTRICLE AND GOES
TO THE LUNGS, ARE
ESSENTIALLY SWITCHED.
>> THE BLOOD THAT COMES BACK
FROM THE BODY GOES BACK OUT
TO THE BODY AGAIN, AND THE
BLOOD THAT COMES BACK
FROM THE LUNGS GOES
TO THE LUNGS AGAIN.
AND OBVIOUSLY,
THAT DOESN'T WORK.
>> BLOOD IS JUST GOING IN
TWO SEPARATE CIRCULATIONS
IN A CIRCLE, AND YOU DON'T GET
ANY OXYGENATION TO THE BODY.
SO THESE CHILDREN CAN GET
INTO TROUBLE VERY QUICKLY
AFTER BIRTH.
>> IN ORDER TO UNDERSTAND
AND TO COMPREHEND ANY
OF THE DIFFERENT FORMS OF
HEART DISEASE THAT EXIST,
IT'S VERY IMPORTANT TO MAKE
SURE WE UNDERSTAND WHAT
THE HEALTHY OR THE NORMAL
HEART LOOKS LIKE.
THE NORMAL HEART
HAS TWO SIDES,
A RIGHT SIDE
AND A LEFT SIDE,
AND FOUR CHAMBERS,
THE TOP RECEIVING CHAMBERS,
OR ATRIUM,
AND THE LOWER CHAMBERS,
WHICH ARE THICK-WALLED
PUMPING CHAMBERS
CALLED VENTRICLES.
RED BLOOD CELL WILL COME
FROM EITHER THE SUPERIOR
VENA CAVA OR THE INFERIOR
VENA CAVA AND ENTER
INTO THE RIGHT ATRIUM.
THE BLOOD THEN FLOWS
ACROSS THE TRICUSPID VALVE
TO THE RIGHT VENTRICLE.
THE RIGHT VENTRICLE THEN
SQUEEZES AND EJECTS THAT
BLOOD CELL INTO A VESSEL
CALLED THE PULMONARY ARTERY.
THE PULMONARY ARTERY
SPLITS INTO TWO VESSELS,
EACH GOING TO THE LUNGS.
AS THAT RED BLOOD CELL MAKES
ITS WAY THROUGH THE LUNG,
IT RETURNS THROUGH THE PULMONARY
VEINS TO THE LEFT ATRIUM.
THAT BLOOD IS
NOW OXYGENATED.
IT'S PICKED UP OXYGEN, THEN
GOES ACROSS THE MITRAL VALVE
INTO THE LEFT VENTRICLE,
WHICH DOES MOST OF THE WORK
IN TERMS OF DELIVERY OF
BLOOD FLOW TO THE BODY.
THAT BLOOD CELL IS NOW
EJECTED INTO THE AORTA
TO SOME ORGAN OR MUSCLE
OR SKIN IN THE HUMAN BODY.
NOW, THERE ARE SOME
SIGNIFICANT DIFFERENCES
BETWEEN THE HEART IN THE
NEWBORN AND THE HEART
IN THE FETUS.
>> THE HEART ACTUALLY IS--
ASSUMES ITS ALMOST
COMPLETE ANATOMY OFTEN
BEFORE A WOMAN WOULD EVEN
KNOW SHE WAS PREGNANT.
>> THE HEART IS ACTUALLY
FUNCTIONING AND PUMPING
BLOOD TO THE BABY THROUGHOUT
MOST OF FETAL LIFE.
>> BECAUSE THE LUNGS ARE
COLLAPSED IN THE FETUS
AND IT'S REALLY THE PLACENTA
THROUGH WHICH MUCH
OF THE OXYGENATION TAKES
PLACE THROUGH THE MOTHER,
THERE ARE VARIOUS BYPASS
PATHWAYS WITHIN THE FETAL
HEART THAT DIRECT
BLOOD AWAY FROM THE LUNG.
THE FIRST IS A STRUCTURE
CALLED THE FORAMEN OVALE.
THAT'S COMMUNICATION BETWEEN
THE TWO TOP CHAMBERS
OF THE HEART THAT ALLOWS FOR
BLOOD TO GO FROM THE RIGHT
ATRIUM TO THE LEFT ATRIUM.
IN FACT, BECAUSE THERE IS
VERY LITTLE BLOOD THAT'S
RETURNING FROM THE LUNG
WHICH WOULD NORMALLY GO
TO THE LEFT SIDE, THE MAJORITY
OF BLOOD THAT FILLS THE LEFT
ATRIUM AND LEFT VENTRICLE
IS COMING ACROSS THE FORAMEN
OVALE FROM THE RIGHT SIDE.
BECAUSE THE
LUNGS ARE COLLAPSED,
THERE'S HIGH PRESSURE, HIGH
RESISTANCE IN THE LUNGS.
AS BLOOD IS EJECTED OUT THE
RIGHT VENTRICLE AND ENTERS
INTO THE MAIN
PULMONARY ARTERY,
VERY LITTLE GOES DOWN
INTO THE LUNGS THEMSELVES.
THE MAJORITY GOES INTO A
STRUCTURE CALLED THE DUCTUS
ARTERIOSUS, WHICH IS
THE SECOND IMPORTANT
COMMUNICATION BETWEEN
THE PULMONARY ARTERY
AND THE DESCENDING AORTA.
THE THIRD STRUCTURE THAT'S
IMPORTANT THAT CONNECTS
THE UMBILICAL VEIN TO THE
FETAL CIRCULATION IS A SITE--
A JUNCTION-- CALLED
THE DUCTUS VENOSUS.
THAT ACTS AS
SOMEWHAT OF A RESISTER,
IF YOU WILL, IN TERMS OF
CONTROLLING THE RETURN
OF BLOOD FROM THE PLACENTA
TO THE FETAL CIRCULATION.
BIRTH IS A WONDERFUL PROCESS
AND AN AMAZING PROCESS,
AND THERE'S A DRAMATIC
CHANGE THAT TAKES PLACE IN
WHAT WE CALL THE
FETAL TRANSITION,
THIS TRANSITION OF THE
CIRCULATION FROM FETAL LIFE
TO NEONATAL LIFE.
AS SOON AS THE
CORD IS CLAMPED,
THE DUCTUS VENOSUS CEASES
TO CARRY BLOOD TO THE HEART,
AND IT BEGINS TO CONSTRICT
WITHIN THE FIRST FEW HOURS
OR DAYS OF LIFE.
THE VERY FIRST THING THAT
HAPPENS WHEN A FETUS IS BORN
IS IT TAKES ITS
FIRST BREATH,
THE LUNGS EXPAND, AND SO
THE RESISTANCE OR PRESSURE
IN THE LUNGS DROP, AND
THAT PROMOTES BLOOD FLOW
INTO THE LUNG ITSELF.
THE DUCTUS ARTERIOSUS
BEGINS TO CONSTRICT
AND IS TYPICALLY FULLY CLOSED
WITHIN 24 TO 48 HOURS
OF LIFE, AND BLOOD IS
NOW THEN FULLY DIRECTED
INTO THE LUNG.
AS THE BLOOD RETURNS TO
THE LEFT SIDE OF THE HEART,
AFTER TRAVERSING THE
PULMONARY CIRCULATION
AND PICKING UP OXYGEN,
THE PRESSURE IN THE LEFT ATRIUM
RISES JUST A BIT, AND THE
TRAP DOOR OF THE FORAMEN
OVALE, WHICH WAS
OPEN BEFORE BIRTH,
NOW BEGINS TO CLOSE, USUALLY
WITHIN THE FIRST FEW DAYS
OF LIFE.
