It was the first beautiful Saturday in spring, and I was in

It was the first beautiful Saturday in spring, and I was in
Beating a
Sudden
Killer
When a young woman nearly
died from a ruptured aneurysm,
the author and the woman’s
husband began searching for
ways to save other aneurysm
patients from catastrophe
BY JOHN A. ELEFTERIADES
It was the first beautiful Saturday in spring, and I was in
charge of my children. We were out browsing the stores
around our local green when the page came in. Lawrence Cohen, a preeminent cardiologist and my colleague at Yale University, was distraught. Normally a
man of few words, Cohen was speaking quickly, almost
feverishly. “I need you, John. In the ER. Right away.
She’s dying, John. She’s dying right in front of me.”
The situation was particularly distressing because
Cohen had been following the woman’s condition for
three years, ever since her husband had come to teach
at Yale. So Carmela Kolman was like a member of the
family. She was 32 years old and had Marfan’s syndrome, a connective tissue disorder that tends to produce thoracic aortic aneurysms: dangerous swellings in
the upper part of the large artery that carries blood
from the heart, down through the chest and into the
abdomen. Left untreated, these aneurysms can grow
until they rupture, an event that is often fatal. The only
64
SCIENTIFIC A MERIC A N
intervention is a preemptive operation to replace the
damaged regions with artificial components. But the
surgery has its own risks, so physicians hold off on
making that call until it seems absolutely necessary.
Because Carmela’s aorta had been only modestly enlarged, Cohen had not recommended surgery.
Yet this Saturday morning Carmela had come to the
emergency room complaining of severe chest pain. A
computed tomographic (CT) scan and an echocardiogram showed an aortic dissection: blood had seeped
through a tear in the inner part of the arterial wall,
causing the inner half of the wall to separate from the
outer half, down the entire length of the vessel. Dissection alone can be deadly, because it can result in blocked
or diverted blood flow, robbing the heart and other organs of essential oxygen and nutrients. But that was not
the worst of the story. The scans indicated that Carmela had blood in her pericardium, the sac that sur-
COPYRIGHT 2005 SCIENTIFIC AMERICAN, INC.
ANEURYSMS, or bulges, in the aorta pose a silent, but
potentially deadly, threat to those who harbor them.
COPYRIGHT 2005 SCIENTIFIC AMERICAN, INC.
havior of thoracic aortic aneurysms: notably, how fast they grow, how to tell
when they are likely to become critical
and who is most susceptible to them.
These insights have helped physicians
decide when to intervene so as to avert
the kind of catastrophic event that
brought Carmela to the ER that Saturday morning.
■
■
66
a s a c a r di ac su rg e on , I focus on
disorders that can damage the heart,
such as thoracic aneurysms. But aneurysms can arise in any artery. A good
number occur in the lower, or abdominal, aorta: the section that runs from the
diaphragm to the area above the pelvis,
where the artery branches to carry blood
to the legs. Research by other investigators has revealed that the mechanisms
underlying the growth, dissection and
rupture of abdominal aortic aneurysms
are similar to those that control the behavior of aneurysms in the chest.
Aneurysms that strike the aorta are
the most life-threatening. Every year
more than 15,000 people in the U.S. die
when an aneurysm in the chest or abdomen bursts or dissects — more people
than die from AIDS. Albert Einstein,
Olympic volleyball star Flo Hyman,
Florida State University basketball player Ronalda Pierce, and actors Lucille
Ball, George C. Scott and John Ritter
were all killed by thoracic aortic aneurysms. Individuals with Marfan’s syndrome are especially susceptible. Medical historians have suggested that Abraham Lincoln might have had this
disorder, a condition that, before surgery
became feasible, killed most victims by
Clinicians have classically been unsure when to operate on an aortic
aneurysm — a swelling in the large artery that carries blood from the heart.
Left alone, an aneurysm could fatally rupture or dissect, the inner layer
peeling away from the vessel wall. But the only proven intervention,
replacement of the damaged aorta with artificial parts, is itself risky.
Detailed analyses of thousands of patients have now led to guidelines for
the best time to operate.
Weight lifters with aneurysms are in particular danger of sudden death while
exercising and should take special precautions.
SCIENTIFIC A MERIC A N
a
Silent Stalker
Overview/Aneurysms
■
The normal aorta (a) is shaped like a candy cane
and is roughly as wide as a garden hose. An
aneurysm, which can occur anywhere along the
tube, is a ballooning of the wall (b), which thins
Ascending
aorta
Descending
aorta
Abdominal
aorta
middle age. Thus, it is possible that our
16th president would have died early
even if he had not been assassinated.
Aortic aneurysms are insidious because they are silent stalkers. The vessel
can balloon without causing pain. Indeed, most people discover their aneurysms while being tested for something
else: a physician will spot the telltale
bulge while performing an ultrasound to
investigate a heart murmur or a CT scan
to evaluate a chronic cough. Pain most
often occurs only when an aneurysm
ruptures or dissects. And it is severe: the
knifelike tearing sensation that accompanies the crisis is described by patients
as being orders of magnitude worse than
the agony of childbirth or kidney stones.
Survival after such an event tends to
be poor. Ruptures usually kill instantly.
In some fortunate cases, however, neighboring tissues can press up against the
rent in the aorta and hold the structure
COPYRIGHT 2005 SCIENTIFIC AMERICAN, INC.
AUGUS T 2005
T A M I T O L P A ( p r e c e d i n g p a g e s)
rounds the heart. So the dissection had
ruptured. She was drifting in and out of
consciousness, her blood pressure was
falling, and she was in shock. She needed surgery immediately.
I left the children with a neighbor
and rushed to the hospital. There my
surgical team and I replaced the weakened part of Carmela’s aorta with an artificial vessel made of Dacron, a fabric
that is woven into a flexible but sturdy
tube. We also traded her damaged aortic
valve, which controls the flow of blood
as it exits the heart, for a mechanical version. After the surgery, Carmela was
very sick. But she clung to life and improved steadily.
Each night on my evening rounds, I
spoke with Carmela’s husband, John
Rizzo, about her condition. As she got
better, we found our conversations turning to more scientific topics, particularly
issues relating to aortic disease.
Rizzo, it turned out, was an economist working in the epidemiology division of the school of public health and
was an expert in data analysis and management. He took a keen interest in my
group’s work, and in the decade since
Carmela’s trip to the hospital, Rizzo has
helped us compile a database containing
the records of all our patients with thoracic aortic aneurysms. As a result, my
colleagues and I now have computerized
information on more than 3,000 patients
with this condition, including some
9,000 images and 9,000 patient-years of
follow-up (when our work with all these
patients is totaled). We know of no larger
organized database on this disorder.
This extensive clinical resource has
allowed us to learn more about the be-
THE PERILS OF ANEURYSMS
and weakens as it enlarges. The condition can be fatal if the tissue
ruptures (c) or dissects (d and photograph), or both. Dissection, the
separation of the inner and outer parts of the vessel wall, results when
blood seeps into the middle of the wall through a tear of the inner lining.
By analyzing thousands of cases, the author and his colleagues have
learned how to predict when an aneurysm is highly likely to rupture or
dissect. Such information can help determine when the need for
corrective surgery outweighs the substantial risks of the procedure.
b
c
d
Vessel wall
Outer wall
Blood
flow
Blood
Examples of
aneurysms
Inner wall
RUPTURE
DISSECTION
S A R A C H E N ( i l l u s t r a t i o n) ; C N R I / P H O T O R E S E A R C H E R S , I N C . ( p h o t o g r a p h)
Cross-sectional view of
dissected aneurysm
together long enough for the patient to
get to the hospital. For dissections, survival depends on the location. If left untreated, those that begin in the ascending aorta — the segment that emerges
from the heart— are fatal within hours
or days. Tears in this area can unseat the
aortic valve, causing shock, or occlude
the coronary arteries, triggering a heart
attack. Dissections in the descending
aorta, which runs down the back of the
chest, are not as threatening: they rupture less frequently than those in the ascending aorta and do not share the same
complications.
Surgery can prevent rupture or dissection, but the operation to replace the
aorta is very serious and as invasive as
procedures get. The operation involves
stopping the heart and shunting the
blood through a heart-lung machine. In
some cases, depending on the location of
the aneurysm, surgeons must shut down
w w w. s c ia m . c o m
blood flow entirely and cool the patient
from 37 to 18 degrees Celsius to slow
metabolism and prevent brain damage
while they repair the aorta. Although
most people do very well after the surgery, the operation carries risks of stroke,
paralysis and death.
To assess whether such a dangerous
intervention is warranted, a physician
must know how likely it is that an aortic
aneurysm will rupture or dissect. In general, a large aneurysm is more dangerous
than a small one. But specific data were
sorely lacking when Carmela fell ill. Although more than 300 papers had been
written on how to operate on the aorta,
we could find precious little information
on how aortic aneurysms behave before
surgery, namely, how fast they expand
and how likely they are to burst or tear at
any given size. Carmela’s aorta, for example, had dissected at 4.8 centimeters
in diameter, a relatively modest size —
COPYRIGHT 2005 SCIENTIFIC AMERICAN, INC.
which was why the event was so unexpected. (The normal thoracic aorta is
typically about 2.5 to 3.5 centimeters.)
Thus, questions regarding aneurysm
growth and stability, we reasoned, were
a good place to begin our investigations.
A Threshold Emerges
to h e l p dr aw this information from
our clinical database, Rizzo fi rst developed sophisticated statistical techniques
that allowed us to determine accurately
the growth rate of aneurysms. We found
that most grow inexorably and surprisingly slowly: only about 0.12 centimeter
per year. Thus, an aneurysm will generally take a decade to grow one centimeter. This finding suggests that aneurysms detected in middle-aged adults
probably began growing when the patients were young adults or earlier.
A statistical method devised by Rizzo
also permitted us to assess the probabilSCIENTIFIC A MERIC A N
67
40
Percentage Point Increase in the Likelihood of
Rupture or Dissection
LARGE ANEURYSM
is shown before
surgery; the
patient is
oriented with
head toward the
bottom right.
30
20
10
0
3
4
5
6
Aneurysm Diameter (centimeters)
7
YEARLY RISK OF COMPLICATIONS
Average Yearly Rate of Complications (percent)
16
14
12
10
Diameter of
Aneurysm (cm)
4.0 to 4.9
5.0 to 5.9
6.0 or greater
8
6
4
2
0
Rupture
Dissection
Rupture or
Dissection
Death
Rupture, Dissection
or Death
PROBABILITIES that rupture or dissection will occur have been calculated for aortic aneurysms in the
chest. In one study, the author and his colleagues plotted risk relative to that posed by small
aneurysms of 4.0 to 4.9 centimeters. They found a dramatic surge in danger when aneurysms
reach six centimeters in the ascending aorta (top graph) or seven centimeters in the descending
aorta (not shown). Another study (bottom graph) revealed that the likelihood of rupture, dissection
or death within the coming year also jumps sharply for aneurysms that reach six centimeters or
higher. (The rates indicated for “Rupture or Dissection” and for “Rupture, Dissection or Death” are
lower than the sum of the rates in individual categories because patients with multiple
complications were counted only once in the combined categories.) Based on such information,
the investigators have determined that many patients with aneurysms in the ascending aorta
need corrective surgery when the artery balloons to 5.5 centimeters.
ity of rupture or dissection for thoracic
aneurysms of different sizes. We were
amazed by the definitiveness of the results. According to our data, the probability of rupture or dissection skyrockets
when an aneurysm in the ascending aorta reaches a diameter of about six centimeters, roughly that of a soft drink can.
More than 30 percent of patients whose
aneurysms reached that size experienced
68
SCIENTIFIC A MERIC A N
a devastating complication, either rupture or dissection. In the descending aorta, the risk shoots up most dramatically
at about seven centimeters.
These numbers represent a lifetime
risk of complication: the chance that an
aneurysm of a given size will rupture or
dissect, although the figures do not indicate when the crisis will happen. But
patients who discover that they have an
aneurysm are more interested in numbers that predict the yearly rate of complication: in other words, whether their
aneurysm might harm them in the near
future.
Determining such probabilities requires a large number of cases, and we
have recently amassed enough data to
begin the appropriate statistical analyses; this data set combines information
from patients with aneurysms anywhere
in the thoracic aorta, although about
two thirds of the patients were affected
in the ascending region. We see a trend
of gradual increase in the probability of
adverse events within the coming year
as the aneurysm grows from 4.0 to 5.9
centimeters and then a sharp jump in
risk once the aorta reaches six centimeters [see bottom graph in illustration at
left]. For instance, we fi nd that for a
thoracic aneurysm of six centimeters or
greater, the risk of rupture, dissection or
death within a year soars to a staggering
15.6 percent. Many forms of cancer do
not carry as great an annual probability
of mortality.
Based on these observations, we recommend that aneurysms in the ascending aorta be surgically removed well before the defect grows to six centimeters.
For most people with no family history
of aneurysms, we suggest operating at
5.5 centimeters. For the descending aorta, we might perform surgery at six centimeters if a patient is healthy enough to
withstand it, but we sometimes delay
until about 6.5 centimeters if the patient
is frail. We operate at smaller sizes than
those listed above for patients with
Marfan’s or a family history of aneurysm-related disorders, as aneurysms in
these people tend to become life-threatening earlier. Using these criteria, we
believe, should prevent the vast majority
of ruptures and dissections without exposing patients unduly or prematurely
to the dangers of aortic surgery. Before
an aneurysm warrants going under the
knife, doctors may attempt to protect
the aorta with medicines that control
blood pressure and slow the heart, to
limit the stress that is exerted on the ballooned wall.
The abdominal aorta is normally
COPYRIGHT 2005 SCIENTIFIC AMERICAN, INC.
AUGUS T 2005
A L I S O N K E N D A L L ( g r a p h s) ; J O H N A . E L E F T E R I A D E S ( p h o t o g r a p h) ; L I N E G R A P H S O U R C E : M . A . C O A D Y E T A L . I N J O U R N A L O F T H O R A C I C C A R D I O V A S C U L A R S U R G E RY, V O L . 11 3 , N O . 3 , P A G E S 4 7 6 – 4 9 1 ; M A R C H 1 9 9 7;
B A R G R A P H S O U R C E : R . R . D A V I E S E T A L . I N A N N A L S O F T H O R A C I C S U R G E RY, V O L . 7 3 , N O . 1 , P A G E S 17 – 2 7; J A N U A R Y 2 0 0 2 .
RELATION OF SIZE TO RISK OF COMPLICATIONS
smaller than the thoracic aorta, and
rupture of the abdominal aorta usually
occurs at smaller sizes than in the thorax. Accordingly, physicians usually intervene surgically at smaller sizes for
abdominal aortic aneurysms. Some authorities recommend intervention at
four centimeters for women and five
centimeters for men, as rough general
guidelines.
to sav e mor e l i v e s , doctors would
benefit from knowing which asymptomatic individuals are at risk for aneurysms,
so that the condition could be detected
early, monitored closely and treated
promptly. Marfan’s syndrome is a wellknown warning; many with the condition wind up having aortic aneurysms.
But people with Marfan’s account for
only 5 percent of all aneurysm patients.
The remaining 95 percent of cases are idiopathic— their cause is not yet known.
Physicians once believed that aneurysms were caused by atherosclerosis —
the accumulation of plaque (fatty gunk)
in the arterial wall. But we have found
that patients with aneurysms in the ascending aorta are actually less susceptible to atherosclerosis than the general
population, so plaque deposition probably is not causal in their cases. Aneurysms in the descending and abdominal
areas, on the other hand, are often accompanied by plaque throughout the
aorta and in its branches, which suggests that atherosclerosis probably does
contribute to those aneurysms.
Our database has revealed that most
thoracic aneurysms have a strong genetic
component of some kind— and the same
appears to be true for aneurysms in the
abdominal aorta and in the brain. Reviewing family histories, we were astounded to discover how often people
with aneurysms report having a relative
with one or a family member who died
suddenly or unexpectedly at a young age.
The latter occurrence is often chalked up
to cardiac arrest, but in many instances
an autopsy would have revealed a ruptured aneurysm. In the 500 families
whose pedigrees we have analyzed, approximately 20 percent display some hisw w w. s c ia m . c o m
WALL OF AORTA became so thin in a six-centimeter aneurysm that a ruler placed behind it can
be seen through the tissue. New findings indicate that aneurysms are caused in part by
excessive activity of enzymes known as metalloproteinases (MMPs), which digest proteins
that are needed for the elasticity of the artery wall.
tory of aneurysm. In most families, the
trait appears to be dominant— in other
words, an individual need only inherit an
“aneurysm gene” from one parent to be
affected; in one of these families, the father passed on aortic disease to all four
of his children. Other families showed
different patterns of inheritance, suggesting that more than one gene can play
a role in susceptibility.
If genetic markers that signify increased susceptibility could be identified, physicians might someday use a
simple blood test to pinpoint those who
need close monitoring — say, by CT
scans or echocardiograms— to catch aneurysms early and determine the best
time for surgery. And if the actual genes
at fault could be found, researchers
might even be able to develop therapies
that specifically counteract their ill effects— potentially slowing or preventing
the growth of aneurysms by blocking
the undesirable activities of the proteins
encoded by those genes.
THE AUTHOR
JOHN A . ELEF TERIADES
All in the Family
With better detection and, ultimately, improved treatment in mind, we have
begun to collaborate with scientists at
Celera Diagnostics in Alameda, Calif.,
to search for genetic markers called
SNPs — single nucleotide polymorphisms — that correlate with aortic disease. SNPs are DNA sequences that differ by a single nucleotide, or code letter,
between one part of a population and
another. James Devlin, Olga Iakoubova
and their Celera team are comparing
DNA samples obtained from 500 of our
patients with thoracic aneurysms and
from 500 healthy individuals, in this
case the patients’ spouses. Then, using
automated equipment, they will scan
some 16,000 genetic regions for SNPs
that appear more often in patients than
in the healthy controls.
Our preliminary work has revealed
a number of SNPs that might signify increased risk, and we are pursuing these
leads in our large patient group. In addition, we are conducting a similar
JOHN A. ELEFTERIADES attended Yale University as an undergraduate and never left. He
graduated magna cum laude with a triple major in physics, French and psychology before
completing his medical degree and clinical training in general and cardiothoracic surgery. Elefteriades is currently professor and chief of cardiothoracic surgery at Yale and
the Yale–New Haven Hospital. He began a weight-training program while on his seventhgrade wrestling team and has been lifting ever since; he benches 75 percent of his weight
and has confirmed, by echocardiogram, that he does not harbor an aneurysm.
COPYRIGHT 2005 SCIENTIFIC AMERICAN, INC.
SCIENTIFIC A MERIC A N
69
A Warning for Weight Lifters
What Goes Wrong
o n c e w e i d e n t i f y the genes in
which aneurysm-related SNPs occur, we
can discern which proteins those genes
encode and learn how they contribute to
aortic malfunction. But already researchers have a sense of some of the
proteins that might be involved. For instance, we know that in most patients
with aortic aneurysms, the stretched
part of the vessel wall shows a loss of
70
SCIENTIFIC A MERIC A N
extremely heavy weights bears the scar of the surgery that saved
his life. Chances are good that a sharp rise in blood pressure during
a workout precipitated the dissection. Even in healthy individuals,
blood pressure can soar to astronomical values, exceeding 300 mm Hg,
during weight lifting (graph).
350
Sedentary former athlete
300
Author, who lifts
weights regularly
250
200
16-year-old athlete
150
100
50
0
25
50
75
100
Body Weight Lifted (percent)
125
body weight or less. Weight lifting can be highly beneficial for
preserving muscle mass and bone strength, but we strongly
advise that individuals who intend to embark on heavy weighttraining programs get an echocardiogram to check for
potential aneurysms before they begin.
— J.A.E.
elastic fibers and collagen as compared
with healthy tissue. Together these proteins give the artery its strength and flexibility. The defects that contribute to this
problem could occur in the genes that
code for those proteins or in other genes
that regulate the manufacture or maintenance of elastin and collagen.
In Marfan’s, the genetic defects that
are at fault usually hobble the gene for
fibrillin, a protein that combines with
elastin to form elastic fibers. As a consequence, the synthesis and deposition of
fibrillin are disrupted, a problem that
presumably weakens the aortic wall and
renders it vulnerable to the formation of
an aneurysm. No one yet knows, though,
whether mutations in the fibrillin gene
are common in patients who do not have
Marfan’s.
We have recently found evidence
that an overabundance of certain enzymes in the aortic wall probably contributes to the formation and growth of
aneurysms in many victims. All blood
vessels harbor enzymes called metalloproteinases (MMPs) that chew up old
proteins to make way for new. The same
vessels also possess inhibitory proteins
that help hold MMPs at bay. In a healthy
COPYRIGHT 2005 SCIENTIFIC AMERICAN, INC.
AUGUS T 2005
J A K E M E S S E R E ( p h o t o g r a p h) ; A L I S O N K E N D A L L ( g r a p h)
study on aneurysm patients in Europe,
to be sure that the findings will hold up
in a different population.
YOUNG MAN who suffered an aortic dissection induced by lifting
Systolic Blood Pressure (mm Hg)
In late 2003 my colleagues and I described in the Journal of
the American Medical Association the tragic occurrence of a
dissection of the aorta in fi ve seemingly healthy individuals
who were engaged in strenuous strength training. Each
unknowingly harbored a bulge in the part of the aorta
emerging from the heart, and the inner half of the distended
wall suddenly, and life-threateningly, separated from the
outer part. At the time of dissection, two were lifting weights,
two were doing push-ups, and the fifth was attempting to lift a
heavy piece of granite. Three were saved by surgical
intervention. We have since become aware
of dozens of additional cases of aortic dissection during
weight lifting, suggesting that the phenomenon is not
a medical rarity.
What might account for this link? Part of the explanation
seems to be that exercise that involves straining against a
fi xed resistance, as weight lifting does, can push the blood
pressure to dangerously high levels. Some studies have
recorded a systolic pressure (that in the arteries when the
heart contracts) of 380 millimeters of mercury (mm Hg) in
competitive weight lifters, as compared with a normal value of
120 or below. We have confirmed such soaring pressures in a
small, three-volunteer study of our own. One of our volunteers
hit 319 mm Hg when lifting just three quarters of his body
weight (graph).
Such pressure can be too much for an already stretched
artery to bear. From separate studies of the mechanical
properties of the distended aorta, we find that at 200 mm Hg,
a six-centimeter aneurysm experiences 800 kilopascals of
pressure — a value that equals the ultimate tensile strength of
the tissue. So it should come as no surprise that an aortic
aneurysm subject to a blood pressure that approaches or
exceeds 300 mm Hg will not hold.
Because of this pressure elevation, we tell athletes with a
personal or family history of aortic aneurysm or any known
aortic enlargement to use great discretion in pursuing weightlifting activities, perhaps limiting bench presses to half their
JOHN A . ELEF TERIADES
aortic wall the activity of these proteins
is balanced, so that protein turnover remains constant. In segments of aorta
removed from our aneurysm patients, in
contrast, we find an excess of two types
of MMP and decreased amounts of one
of the inhibitory proteins.
This imbalance could lead to an enhanced degradation of proteins, including elastin and fibrillin, in the aortic
wall — a situation that might pave the
way for thoracic aortic aneurysms by
weakening the vessel wall. In one patient, the aorta had become so thin that
the markings of a ruler could be read
through its wall. Other scientists have
also found evidence of a role for overzealous MMPs. These fi ndings suggest
that drugs able to block MMP activity
might help retard growth or forestall
rupture of aortic aneurysms, but study
of this concept is just beginning.
With our Yale colleague George
Koullias, we have recently begun to assess the mechanical properties of the
dilated aorta to better understand why
it becomes more dangerous as it enlarges. Before surgically removing an aneurysm, we measure its diameter, the
thickness of its wall, and the blood pressure as the heart contracts and relaxes.
From these parameters we can calculate
the vessel’s mechanical properties.
We have shown that as the aorta
grows larger its distensibility, or ability
to stretch, falls. We have also demonstrated that by the time an aneurysm in
the ascending aorta reaches six centimeters— the same critical value we encountered in our previous studies of aneurysm behavior— the vessel behaves as a
rigid tube. This stiffening maximizes
the stress that gets absorbed by the wall
of the aorta as blood pounds against it
with every heartbeat and helps to explain why trouble often ensues when an
aneurysm hits the crucial dimension of
six centimeters.
Inflexibility sets an aortic aneurysm
up for disaster. But what sends it over the
edge? We have begun to categorize the
specific events that cause dissection to
occur at one particular moment in time
in a susceptible individual. After interviewing patients in our database, we find
w w w. s c ia m . c o m
Who Should Worry
In some ways, an aortic aneurysm is like a time bomb in the chest. It can sit
silently until one day it ruptures or dissects. But certain conditions often signal
a susceptibility to aortic aneurysms:
■
■
■
A family history of aneurysms
Having someone in the family
collapse and die suddenly or
unexpectedly
Marfan’s syndrome or its hallmarks.
These include long limbs, a tall, thin
frame and loose joints (such as are
evident in the ability, shown at right,
to cross the thumb all the way over the
palm while keeping the hand flat)
My colleagues and I tell patients who meet any of these criteria — or who plan
on engaging in serious weight training — to have regular CT scans or echocardiograms to check for aneurysms. Weight training does not elevate risk for having an
aneurysm, but, as noted in the box on the opposite page, it can increase the
likelihood that an existing aneurysm will suddenly become lethal.
—J.A.E.
that nearly three out of four recall experiencing an intense episode of extreme
emotion or physical exertion immediately preceding the dissection. What
these activities have in common is that
both presumably cause a spike in blood
pressure that splits the vulnerable aorta.
For one class of athletic activity— weight
lifting— we have specific evidence that
this is the case; indeed, this activity can
put so much stress on an aneurysm that
it prompts a crisis even when the swelling has not crossed the six-centimeter
mark [see box on opposite page]. It seems
logical to surmise that pressure spikes
from other events could also induce rupture, although we have not looked at
that possibility directly yet.
The renowned 19th-century physician Sir William Osler once observed
that “there is no disease more conducive
to clinical humility than aneurysm of the
aorta.” Today investigations into the biology and behavior of thoracic aortic aneurysms— from the genetic susceptibility
that drives their formation to the physical or emotional events that cause them
to blow out or tear— are helping to render
the condition a little less humbling.
As for Carmela, she continues to be
in good health and has returned to her
work as an artist. “I know it sounds clichéd,” she says, “but I feel I’ve been given a second chance to live my life”— a
chance her father did not have when he
died from an aortic dissection at the age
of 34. We hope that our research, inspired by Carmela’s crisis that terrifying
spring day, will provide many others
with the same opportunity.
MORE TO EXPLORE
Surgical Intervention Criteria for Thoracic Aortic Aneurysms: A Study of Growth Rates
and Complications. Michael A. Coady et al. in Annals of Thoracic Surgery, Vol. 67, No. 6,
pages 1922–1926; June 1999.
Yearly Rupture or Dissection Rates for Thoracic Aortic Aneurysms: Simple Prediction Based
on Size. R. R. Davies, L. J. Goldstein, M. A. Coady, S. L. Tittle, J. A. Rizzo, G. S. Kopf and
J. A. Elefteriades in Annals of Thoracic Surgery, Vol. 73, No. 1, pages 17–27; January 2002.
Weight Lifting and Rupture of Silent Aortic Aneurysms. John Elefteriades et al. in Journal of
the American Medical Association, Vol. 290, No. 21, page 2803; December 3, 2003.
Perspectives on Diseases of the Thoracic Aorta. John A. Elefteriades in Advances in
Cardiology, Vol. 41, pages 75–86; 2004.
Kevin Helliker and Thomas M. Burton’s Wall Street Journal series on aortic aneurysms:
www.pulitzer.org/year/2004/explanatory-reporting/works/
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