>> WHEN I WAS PREGNANT WITH JOSEPH,
WE EXPECTED JUST TO HAVE ANOTHER NORMAL PREGNANCY,
NORMAL CHILD.
AND I WENT TO FIND OUT IF HE WAS A BOY OR A GIRL,
AND INSTEAD OF FINDING OUT THAT,
WE ALSO FOUND OUT THAT HE HAD A HEART PROBLEM.
THAT WAS VERY SHOCKING AFTER HAVING HAD HEALTHY BOYS BEFORE.
>> WE HEARD--IT WAS JUST BEFORE CHRISTMAS,
SO IT WAS--YOU KNOW, IT WAS A BAD TIME AND,
YOU KNOW, I MEAN ALL OF US, EVERYONE IN THE FAMILY
PULLED, YOU KNOW, TOGETHER.
>> IT WAS VERY HARD ON ME TO BE PREGNANT AND TO BE THAT
SAD AND SCARED AND ALSO TO HAVE MY OTHER TWO CHILDREN
TO TAKE CARE OF WHEN I HAD ALL THAT CONSTANTLY
IN THE BACK OF MY MIND.
>> 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 A 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.
>> AND CHILDREN WITH A HEART DEFECT BORN TODAY,
I AM SURE, ARE GOING TO HAVE A MUCH BETTER OUTCOME AT AGE
50 THAN SOMEBODY BORN 30 YEARS AGO.
>> IT USED TO BE WE WERE JUST TRYING TO GET THE BABIES
TO SURVIVE TO DISCHARGE, AND NOW WE'RE REALLY FOCUSING
ON MORE THAN THAT.
NOW WE'RE FOCUSING ON HOW TO GIVE THE PARENTS A BETTER
CHILD TO TAKE HOME.
>> AND AS THINGS CONTINUALLY IMPROVE,
AND AS THESE CHILDREN HAVE ISSUES WHEN THEY GET OLDER,
I HAVE NO DOUBT WE WILL HAVE WAYS TO TREAT THOSE ISSUES.
SO I DON'T SEE ANY REASON TO BE PESSIMISTIC ABOUT
THE LONG-TERM OUTLOOK FOR THESE CHILDREN.
>> THE TERM "SINGLE VENTRICLE" RELATES TO A SERIES
OF ABNORMALITIES IN WHICH NATURE HAS ONLY ALLOWED
FOR THE DEVELOPMENT OF ONE PUMPING CHAMBER.
NORMALLY, THERE SHOULD BE TWO VENTRICLES,
ONE ASSIGNED TO DELIVERING BLOOD TO THE LUNG,
ONE ASSIGNED TO DELIVERING BLOOD TO THE BODY.
BUT THERE ARE A VERY WIDE SPECTRUM OF ABNORMALITIES
IN WHICH THERE IS FUNCTIONALLY, OR EVEN ANATOMICALLY,
ONLY ONE PUMPING CHAMBER.
>> THIS IS A REALLY COMPLEX GROUP OF LESIONS IN GENERAL,
AND FROM A MEDICAL STANDPOINT,
THEY'RE CATEGORIZED THROUGH A NUMBER OF COMPLEX
ANATOMICAL NAMES.
BUT PRACTICALLY, YOU CAN DIVIDE THEM INTO SORT OF
THREE DIFFERENT CATEGORIES.
THE FIRST WOULD BE THOSE IN WHICH IT'S DIFFICULT
FOR BLOOD TO GET FROM THE HEART OUT TO THE BODY.
SECOND WOULD BE THOSE IN WHICH IT'S DIFFICULT TO GET
BLOOD FROM THE HEART TO THE LUNGS.
AND THE THIRD IN WHICH THERE'S A BALANCE SITUATION
IN WHICH BLOOD GETS BOTH FROM THE HEART TO THE LUNGS
AND THE HEART TO THE BODY, AND YET YOU STILL CAN'T USE
TWO VENTRICLES.
YOU CAN ONLY USE ONE PUMPING CHAMBER.
>> 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.
SO ONE CAN IMAGINE THAT IF YOU ARE SOLELY DEPENDENT ON
YOUR ONE VENTRICLE TO DO THE JOB OF DELIVERING BLOOD
TO THE BODY, ONCE THAT DUCTUS ARTERIOSUS BEGINS
TO CONSTRICT OR CLOSE, THEN THERE'S NO WAY FOR BLOOD
TO GET TO THE BODY, AND UNFORTUNATELY THESE BABIES--
THESE BABIES DIE.
>> BUT IF WE KNOW A COMPLEX LESION IS COMING UP,
A CHILD THAT'S SUFFERING FROM ONE OF THESE,
WE CAN PREPARE FOR THAT AHEAD OF TIME.
>> WE CAN AVOID HAVING A SUDDEN CARDIAC ARREST
AT HOME, OR EVEN DEATH, SUDDEN DEATH AT HOME,
BY KNOWING THAT THE BABY HAS THE HEART DEFECT.
IF NECESSARY, WE CAN ARRANGE TO HAVE THE BABY DELIVERED
AT CHOP--
>> IN A MUCH MORE CONTROLLED TREATMENT STRATEGY.
SO THAT'S A HUGE ADVANTAGE IN TERMS OF PRENATAL DIAGNOSIS.