+++
Pregnancy and
Contraception
++
Risk stratification for maternal outcomes for pregnancy are limited. Table 500-1 provides our best current practical guidelines
for counseling patients regarding risks. Collaborative management
by a pediatric cardiologist, or adult cardiologist with experience
in congenital heart disease, and a perinatologist is optimal.
++
++
Prevention of pregnancy with steroidal birth control increases
the risk of thromboembolic events and is contraindicated in patients
with residual right-to-left shunts, pulmonary hypertension, and
single ventricles with passive pulmonary blood flow. Alternative
approaches should be utilized.
++
Physical exertion at some level is beneficial for almost all
people, including those with congenital heart disease. The goal
is to balance the beneficial effects of increased cardiac work associated
with exercise with the risk of disease progression or serious injury
and death, which may occur. Making recommendations for the type
or extent of physical activity for children with congenital heart
disease is quite difficult and secondary to the heterogeneity within
defects. In addition, secondary to changes in surgical techniques
and the timing of interventions, there is a lack of data in making
recommendations for various lesions for which we have not necessarily
had enough time to know the long-term risks.
++
The 36th Bethesda Conference, published in 2005, deals with eligibility
recommendations for competitive athletes with cardiovascular abnormalities.1 As
such, it does not deal with recreational activities or physical
education at school. Generally, sports are broken down into categories
based upon the amount of dynamic and static activity (eTable
500.1). All exertion and physical activity can be broken down
into these components. Restrictions for patients with congenital
heart disease vary depending on the actual increase on myocardial
oxygen demands and the physiologic stress placed on the underlying
cardiac conditions. For instance, wrestling, a sport with a high
static component, is not recommended for patients with moderate
or severe aortic insufficiency, as it potentially will increase
the amount of leakage. It should also be noted that the exact classification
of some sports varies in the amount of dynamic and static components from
training to competition. Many sports not considered to have a high
static component during competition include training sessions with
weightlifting. Training regimens may need to be modified. Different
positions in different sports also have very different physical
demands. Examples would include goalie versus a midfielder in soccer,
a catcher versus first-base player in baseball, and an offensive
lineman versus wide receiver in football. In addition, bicycling
will vary on whether a ride is level or up hill with an increasing
static component as the grade or slope increases. Exercise activities
are also classified as to whether there is a collision risk or increased
risk secondary to dizziness or momentary loss of coordination. For
instance, patients with pacemakers and patients who take anticoagulation
agents such as Coumadin or enoxaparin will have restrictions that
are not related to myocardial demands.
++
++
Patients with cyanotic heart lesions usually restrict themselves, because they become more cyanotic with increasing
physical effort. They may participate in physical education at school
but must be allowed to rest or stop, and they should not be forced
or induced to do any competitive activity, such as running a mile
for time or performing so many push-ups or sit-ups. Most children
with repaired lesions can participate in all sports. The timing after
repair will depend on the type of surgery or intervention. Patients with
atrial and ventricular septal defects that are repaired surgically must
wait 3 to 6 months before full participation in sports. They should have
an echocardiogram and EKG to make sure that they do not have any
arrhythmias, pulmonary hypertension, or ventricular dysfunction. Patients
with atrial septal defects, especially those closed after childhood,
may have tachyarrhythmias as long-term sequelae and should be followed
for this possibility. Small atrial septal defects/patent
foramen ovales and ventricular septal defects with QP/QS ratios
of less than 1.5:1 are not always repaired. These patients are cleared
for all activity, except for patients with atrial septal defects and
patent foramen ovales who should not scuba dive, secondary to the
risk of embolic stroke. Moderate-to-large atrial septal defects, ventricular
septal defects, and patent ductus arteriosus are usually repaired
either by surgery or interventional catheterization once they are
found in children old enough to compete competitively (approximately
age 12 years). They can participate in routine exercise, as long
as they are allowed to rest and limit their exertion until they
are repaired.
++
Tetralogy of Fallot patients should not compete in any sports
until after they are repaired. Their postrepair recommendations
depend on right ventricular function, volume and pressure, and on
the presence or absence of atrial or ventricular arrhythmias. The
right ventricular volume should be normal or only mildly enlarged,
and the right ventricular pressure should be less than one-half
systemic. They should have exercise stress tests to specifically
look for ventricular arrhythmias, because many have had a ventriculotomy
as part of the repair.
++
Asymptomatic patients with aortic stenosis, including subvalvar
and supravalvar stenosis, who have mild stenosis, defined as a mean
gradient of less than 25 mmHg by echocardiogram or as a peak gradient
of 30 mmHg in the catheterization lab, can participate in all sports
as long as they have a normal ECG. Asymptomatic moderate aortic
stenosis defined as a catheterization gradient of 30 to 50 mmHg
or a mean gradient of 25 to 40 mmHg on echocardiogram may participate
in some sports, but they will need an echocardiogram/exercise
testing prior to approval. Patients with severe aortic stenosis
should not participate in competitive sports or in physical education
at school, and their level of exercise should be adjusted by a cardiologist. Because
all forms of subvalvar, valvar, and supravalvar aortic stenosis
tend to progress with time, these patients will need serial follow-up
every 1 to 2 years with the possibility of a change in recommendations.
++
Pulmonic stenosis is very well tolerated, and as long as the
right ventricular pressures are less than one-half systemic and
the right ventricular function is normal, patients should not have
any restrictions. Patients with a peak gradient by echocardiogram
of more than 50 mmHg undergo intervention, usually by catheterization. Following
intervention, if they have right ventricular pressures less than
one-half systemic, good right ventricular function, and only mild pulmonary
insufficiency, they can participate in all sports 2 weeks postcatheterization
intervention and 3 months postsurgical intervention.
++
D transposition (simple transposition) patients at present
will almost all have had arterial switch repairs. The important
caveat to remember here is that their coronary arteries were moved
as part of the operation. They should all undergo exercise stress
testing prior to approval for competitive sports. Additional sequelae
that may affect their ability to participate are supravalvar pulmonic
stenosis or supravalvar aortic stenosis and dilation of the neoaortic
root. Fontan patients are such a heterogeneous group, that it is
difficult to predict how they will react to physical exertion.
++
Coarctation patients also have their own set of considerations.The
first is to remember that they often have other associated lesions,
including subaortic stenosis, bicuspid aortic valve, aortic stenosis,
and dilated aortic roots that must also be factored into exercise
participation. Patients after repair will sometimes have mild residual
gradients at rest, a recurrence of a gradient with exercise, left
ventricular hypertrophy or systemic hypertension. Patients repaired
by stent or balloon angioplasty should have magnetic resonance imaging (MRI)
to look for aneurysms prior to competitive sports participation.
++
Kawasaki disease is now the most common type of acquired heart
disease. Aneurysms will develop in 4% of those patients
treated with high-dose gamma globulin in the acute phase. The risks
of exercise in individuals depend on the degree of coronary involvement. There
are two avenues for the development of coronary ischemia from Kawasaki
disease. Coronary thrombi may form in large aneurysms and spread
distally if the aneurysms do not resolve. Second, since coronary
aneurysms represent a vasculitis and damage to the coronary wall,
progressive coronary artery stenosis may develop. The limitations
are varied, and the most important piece of information to remember
is that patients who develop aneurysms need stress testing with
myocardial perfusion imaging to delineate their safe exercise levels.
++
Oxygen delivery to tissues is equal to the oxygen content of
the blood times the cardiac output. Exposure to higher altitudes
where the partial pressure of oxygen (PO2) and inspired
oxygen (PIO2) are reduced, decreases alveolar oxygen (PaO2) as
can be calculated from the alveolar gas equation: PaO2 = PIO2 – PaCO2/R + F
R is the respiratory quotient, normally about 0.8, and F is the
correction factor, usually less than 2 mmHg. The normal PIO2 is
about 150 mmHg and is equal to 21% of 760 mmHg (barometric pressure
minus 47 mmHg) water vapor pressure. The partial pressure of oxygen
(PO2) is determined by barometric pressure, and the barometric
pressure decreases as altitude increases. Because the oxygen dissociation
curve is S-shaped, it does not show a significant decrease in oxygen
saturation until the PO2 is about 60 mmHg.
++
When there is normal cardiopulmonary function, alveolar oxygen
PaO2 is about 100 mmHg. The difference between alveolar
and arterial oxygen (AaDO2) is normally less than 15 mmHg, producing
arterial PaO2 of at least 85 mmHg and oxygen saturation
in the high 90s. In practical terms, up to a level of 3000 feet,
there is no response to altitude because there is essentially no change
in oxygenation. The oxygen dissociation curve is almost horizontal
at this point. The PaO2 at 5000 feet is 82 mmHg, and the oxygen
dissociation curve starts to become more vertical at this point, although
the slope is shallow. Between 5000 to 10,000 feet (moderate elevation)
the slope of the curve is still not steep, but there will be changes
of oxygen saturation and initiation of physiologic responses to
the decreased oxygen saturation (hypoxia). An elevation of 10,000
feet corresponds to a PaO2 of 62 mmHg. Above 10,000 feet, high
altitude, the oxygen dissociation curve is much more vertical, and
increases in altitude cause much more precipitous falls in PaO2 and
O2 saturation and stronger physiologic responses.
++
The heart lesions which do not tolerate the physiologic increase
in pulmonary vasoconstriction caused by hypoxia (increased altitude) include
single ventricles with Fontan circulation, as these patients do
not have a ventricle to pump blood to the pulmonary circulation. In general,
Fontan circulation patients will tolerate increased altitude if
they have an atrial fenestration, but this improved toleration depends on
the reason for the presence or continued presence of the fenestration
(eg, some centers only fenestrate high-risk Fontans, and these high-risk
patients would be expected to do poorly with any added stress). Other
patients who have the potential to be affected at moderate altitudes
include patients with pulmonary hypertension from pulmonary vascular
disease and patients with either severe tricuspid regurgitation
(eg, Ebstein anomaly), severe pulmonary insufficiency (eg, tetralogy
of Fallot status posttransanular patch repair or with longstanding
homograft valves), or both. This intolerance to altitude will be
increased if exertional activity is involved, as the reduced alveolar
oxygen tension created by exercise may increase pulmonary vasoconstriction.
++
Patients with cyanotic heart disease and those with Fontan physiology
should live below 5000 feet (low altitude) so that there will not be
a significant compromise of O2 delivery to the body or
a significant increase in pulmonary vasoconstriction. They usually
will be able to visit moderate elevations, 5000 to 10,000 feet for
short periods, such as airline flights without sequelae. The longer
they stay at elevation and the closer the elevation is to 10,000
feet, the more likely they are to develop symptoms and distress.
Trips to relatives who live at moderate elevation or family ski
vacations should have contingency plans that allow the patient to
return to low altitude quickly. Even if they are not symptomatic
at rest, their exercise tolerance will likely be affected. Supplemental
oxygen will be helpful in alleviating symptoms.
++
All commercial airlines carry supplemental oxygen, but they have differing
policies on the use of supplemental oxygen, and it is wise to contact
and arrange ahead of time the O2 delivery system to be
used. (In this day and age, expect to be charged a handsome supplemental fee.) Commercial
aircraft can maintain a cabin pressure equivalent to sea level or
local ground level up to an altitude of 22,500 feet. Above that
altitude, cabin pressure will start to decrease, inducing lower
arterial saturation/PO2 in the travelers. The
maximum altitude allowed is roughly 9000 feet, but at usual cruising
altitudes, the cabin pressure is usually 7000 to 8000 feet. Because
most flights are of short duration (less than 6 hours) and there
is little physical activity, commercial flights are well tolerated.
Special consideration for layovers at altitude must be considered
in planning travel.
++
Another travel consideration is the actual altitude to be visited.
Most major US cities are listed at elevations near or below 5000
feet (low altitude). Unfortunately, some of the cities at around
5000 feet are situated in mountain valleys, and some of their greater
metropolitan areas may be at much higher elevation. For example,
Albuquerque is listed at an elevation of 4945 feet, and Salt Lake
is listed at an elevation of 4390 feet, but both cities have associated
areas of between 7000 and 8000 feet of elevation. Long-term plans
for higher education and job selection will also be affected by
altitude. In the western United States, some schools are located
at high altitudes, and school performance and the possibility of
having to be more self-sufficient while away at school can be quite
demanding.
++
Patients with severe tricuspid regurgitation, severe pulmonary
insufficiency, tricuspid regurgitation and pulmonary insufficiency,
or right ventricular dysfunction will be increasingly affected at
increasing moderate elevation. They can be expected to have the
same problems as Fontan circulation patients at moderate elevations
when they live at high elevations, and they should live below 10,000
feet in elevation. Every patient will vary in their clinical response,
so recommendations in medications need to be customized. Most effects
of elevation are reversible over time, although subsequent response
to hypoxia may be more vigorous.
++
Patients who should remain at low altitude also include unrepaired
tetralogy of Fallot and unrepaired tetralogy of Fallot physiology patients
(eg, tricuspid atresia, ventricular septal defect, pulmonic stenosis,
and transposition ventricular septal defect pulmonic stenosis, because
they are at risk of hypoxic (hypercyanotic episodes). They should
not fly or visit moderate or high altitude until they are repaired.
The patient with an absent pulmonary artery on the side opposite
the aortic arch (a rare condition) should not spend time in elevations
above 5000 feet because of the risk of acute pulmonary edema.
++
Besides supplemental oxygen, there are now other medical options
to aid patients who are planning visits to moderate and high altitudes or
who have pulmonary vasoconstriction. Phosphodiesterase type-5 inhibitors,
such as sildenafil, have a rapid onset of action, and they may be
started a few days prior to the expected change in altitude. The
endothelin blocker bosentan would not be a good choice, since it does
not achieve its maximal effect for weeks or months after institution
of therapy. There is also a much higher risk of side effects. Inhaled (nebulized)
iloprost a stable analog of prostacyclin is another alternative.
Because it is inhaled, side effects are uncommon and include headache,
flushing, and most importantly hypotension. The major limitations
are the frequency of application, up to 6 times per day, and the
need for a nebulizer. The L type calcium channel blocker, nifedipine,
is also effective at treating pulmonary edema caused by acute pulmonary
hypertension.2-6