Current Trends in the Prevalence of Adult Congenital Heart Disease (Slides with Transcript)

I am going to give you an overview of adult congenital heart disease (ACHD). I will also discuss the unique group of patients that we are going to talk about in our subsequent talks in terms of therapies for those patients. This population is growing. In almost every journal, almost every month, there is an article about adults with congenital heart disease (CHD), so it is an important population. No matter whether you come from a pediatric cardiology background or an internal medicine cardiology background, these patients will be in your practice.

Congenital heart disease is present in about 0.8 % of all live births, and I put a question mark there because we still don't know the incidence. A number of patients are born with CHD, but certainly we find them in adulthood as well with ASDs and congenitally corrected transposition, so the exact incidence is not always known.

If you are a mom with CHD and you have a child, your risk of having a child with CHD is about 3% to 6%, so it is again about a 5 to 7-fold increase, but still only about 3% to 6%. With some types of congenital heart lesions, such as left-sided obstructive lesions, we see a bit higher incidence of transmission to a fetus.

Although there are some genetic associations, as well as known toxins and viral causes, the majority are still without a known cause. Trisomy 21, we all know, has a higher incidence of ventriculoseptal defects (VSDs) and atrioventricular septal defects (AVSDs), as does 22q deletion in terms of great artery malformations. Other causes include maternal use of lithium during pregnancy, Ebstein anomaly, rubella, and peripheral pulmonary artery stenosis, but in most of the patients born with CHD, we do not know the etiology.

Many anatomic abnormalities can be affected by CHD, certainly ASDs, and defects in the upper portion of the septum, primum. We have right-side obstructive lesions, suggested tricuspid atresia, pulmonary valve atresia, and again, anything along this pathway here could be affected. We have VSDs; the location of the defect and the size of the defect definitely portends prognosis in these patients and determines how to treat these patients. We have anomalous pulmonary venous return; we have left-sided obstruction -- it could be at the mitral valve level, below the aortic valve, subaortic valve obstruction, aortic valve obstruction, coarctation of the aorta, and then single ventricle complexes -- right ventricular complexes, left ventricular complexes, in which the patients have to go through a pathway of single ventricle repair, and transposition complexes as well, transposition and congenitally corrected transposition and detransposition.

We see a wide variety of lesions in CHD, and we can categorize them primarily by pathophysiology and somewhat by anatomy. We see shunt lesions in the right-side and left-side obstruction, and how these patients are treated either surgically or with palliative repair

Every patient is quite unique, and adults with CHD comprise a very unique population varying widely by the surgery they have had, palliation, the type of anatomy.

What is a successful outcome? What do we consider a successful outcome for a patient or a child born with CHD? In the past, we were trying to just get them through the initial surgical repair, and if we could do that, it was considered a successful outcome. Another successful outcome was surviving the first year of life. Infant mortality rates are always looked at in CHD centers, so just surviving that first year was important. Having a normal childhood -- we hope that our children born with CHD will have a normal childhood and be able to do the things that other children can do, normal adolescence. Finally, surviving to adulthood is certainly a benchmark that we look at in terms of the era in which we are treating patients, and getting them to adulthood is very important. We will discuss about what surviving to adulthood means in a minute.

Let's look at surviving to adulthood by decade, and these statistics are for simple and moderate and complex. All lesions have an estimate of averages. Based on the decade, in 1940 about 30% of those born with CHD would have made it to adulthood, and. since we did not have cardiopulmonary bypass and complex repairs, most of those were simple lesions -- VSDs, and some of the more balanced lesions. ASDs, of course, would have made it to adulthood.

By the 1960s, with the advent of cardiopulmonary bypass and some of the repairs that we do, the survival rate went all the way up to 65% and in 1970 75%. By 1980, 85% to 90% of all lesions -- simple, moderate, and complex -- we expected to make it to adulthood.

If we look at just complex lesions, only about 5% of patients would have survived in 1940 -- again, they would be very balanced lesions such as the patient with a single ventricle and pulmonary stenosis, or VSDs or tetralogy of Fallot (TOF)–type patients. In 1960 15% and only 1% of transposition patients would have made it to adulthood; about 10% of TOF patients probably would have made it to adulthood. In 1970, again, we saw the greatest change. From 1980 until now, 80% to 90% of those patients with complex lesions have been expected to make it to adulthood. If you could look back over time and see what has happened over the last 2 or 3 decades, all patients, the majority of patients are expected to make it to adulthood, which has changed the landscape of CHD.

We start with an incidence that really doesn't change--this incidence has not changed much over time. Yet, with early diagnosis and advances in intensive care unit (ICU) care and improved surgical techniques, we do early complete repair instead of palliative-type repairs; we lower perioperative mortality and increase early mid-term survival. Then we have this expanded population of adults with CHD. For multiple reasons, not just one reason, this expanded population now exists,

If we look at raw numbers -- these are just estimates -- we propose that there are about a million adults with CHD now, and at the current rate, we will have about 1,300,000 by the year 2010. The incidence goes up by about 20,000 new patients a year, at about a 5% increase a year. This number is going to continue to rise as the population ages. The pediatric population will stay fairly constant, and the adult population will continue to rise.

Taking the CHD population as a whole, in the 1960s, there was about a 70/30 split between adult and pediatric patients, with the majority being pediatric patients. By 1985 there was about a 50/50 split. Since about the year 2002-2003, we think that the shift has gone more towards adult patients, so that today, there are more adults with CHD than pediatric patients, and again, the latter continue to age and survive at a much greater rate. Right now, the ratio is about 1,000,000 to 600,000, and this will continue to rise on the adult side, most likely.

These are some data from the Mayo Clinic showing some of their population of patients, greater-than age by diagnosis and age. By far, the majority of their patients are complex – this may be a selected group because when you are a large referral center, you are going to be referred patients that are much more complex than some of the patients with an ASD or a VSD, who may be taken care of outside of a select center. It gives you a feel for the types of diagnoses they see in that particular clinic, and again, patients are aged greater than 40, this is nice picture in terms of ages of patients.

These are European data from the CONCOR Registry (from the Netherlands) that they pulled together from about 10 universities or academic centers, and it is more updated information than 2005. Again, TOF is a large population. This other group had a mixed bag of different types of diagnoses, but here is coarctation of the aorta and VSD, so again, a wide range of diagnoses are seen in these large clinics in these large registries.

From the Mayo Clinic and from Toronto, you can look at the age of the patients they are seeing in their clinics – somewhat of a bell-shaped curve. The majority of patients are in the prime of life; they are in their 20s, 30s, and early 40s. In this age group, we see patients who want to become pregnant in so again, a large portion of patients are in this 20 to 30–age group. We see the same with this bell-shaped curve of patients with the Toronto clinics, but again, we still see patients in their 40s and 50s now as well.

These are European data from that same CONCOR registry. Again, patients in their 20s and 30s make up the majority of the patient group. These patients are in the prime of their life, in their 20s and 30s, and 85% were less than 45 years of age in this registry of about 5000 patients.

In this large population, the question then becomes what is happening to those patients as they reach adulthood? They are reaching adulthood, but what is happening with this large group of patients?

These are Michael Silka's data from the Oregon Health Systems, from about 3500 patients. They looked at survival, sudden cardiac death–free survival, postoperative years after having the repairs, and if you look at TOF, as well as coarctation of the aorta, again, patients do well for the first 10 to 15 years, but then they rapidly start dropping off the curve. Remember, these patients are young, in their 20s and 30s, so their instance of sudden cardiac death is somewhere around 25 to 50 times greater than the norm for people their own age. Aortic stenosis and transposition are even worse in terms of prognosis and outcome, so when we look at these data, we see a much greater instance of sudden cardiac death than we had ever thought there would be.

Those were Oregon's data, and here are data from Europe, again showing the mean age of death for tricuspid atresia, transposition, coarctation, and again, much younger than we had ever expected, this incidence of sudden death, congestive heart failure, and perioperative in terms of causes of death in this population. There is a large population in this age group, but unfortunately this age group seems to not be surviving as long as we expected it to.

Morbidity is also an issue. These are data from Royal Clinic showing hospital admissions over time. If you look at the age 12 to 19, it is fairly steady, in terms of from this era to here, if you look at age 20 to 29, a much greater increase from less than 50 hospital admissions to about 150 or so. But look at greater than age 30 -- we see this in all of our hospitals-- less than 50 admissions, but now 250 admissions for the greater than 30-year-old age group with CHD. We are seeing them in the clinic, in the hospital, in much greater proportion than ever.

Why is this happening in terms of the morbidity and mortality issue for these patients? Adults with CHDs have arrhythmias -- atrial arrhythmias, ventricular arrhythmias, sudden cardiac death, and vascular lesions. They have valvular heart disease, residual shunts, and then heart failure, and not only right-heart failure, but left-heart failure, systolic and diastolic dysfunction, and pulmonary arterial hypertension (pulmonary hypertension). Every facet of cardiology care can be affected by these patients. Most of us who take care of patients in this group find that normally our patients don't have just one of these problems, they have multiple problems -- arrhythmias along with valvular heart disease or heart failure.

How about the arrhythmia risk? These data are from this large database from Europe. We have arrhythmias in 5000 patients; some of the main diagnoses are shown on the bottom of the graph. Look at the supraventricular incidence and the prevalence. About 50% of our Fontan patients will have atrial arrhythmias we have to deal with, and these are very complex lesions, not simple forms of atrial arrhythmias. They are very difficult to control and to treat -- patients with transposition have multiple suture lines within the atria; there is hemodynamic load; there is enlargement of the atria, causing atrial arrhythmias.

The ventricular incidence is much less, but still, quite significant, particularly for TOF and transposition -- 2 of the lesions that I presented earlier, quoting the fact that they have a high instance of sudden cardiac death.

As I leave arrhythmias, it is important to know that today, we do not have primary prevention for this patient group. Even though we know they have a high incidence of ventricular arrhythmias and sudden cardiac death risk, we still don't have good criteria for primary prevention in this age group. Something for the future.

Vascular lesions, again, are common in our patient group. Here is a patient with coarctation of the aorta that has had repair with a restenosis. Here is coarctation of the aorta; on the other side is another more complex-looking aorta, in which there is stenosis and a little bit of dilation or aneurysm beyond that site.

This 28-year-old with coarctation of the aorta repair came in for a routine visit actually feeling well. We do a lot of screening studies on our patients, and when we did this screening study, we found a huge aneurysm, almost a 7-cm aneurysm, at the site of the coarctation repair, obviously a very concerning a lesion. Again, we see this type of aneurysm in another gentleman who is in his 40s who came with hypertension but really no other symptoms. We found a large aneurysm that we need to deal with, so we do have vascular lesions.

On the left side, we see a 48-year-old with repaired TOF. You can see the right-ventricular outflow tract in severe pulmonary stenosis, both the branch of the right and left pulmonary artery. They could have these with prior shunts, but in this case, probably part of the anatomy and the repair of TOF. These are very difficult lesions. Dr. Hellenbrand will talk about how we treat some of these lesions.

On the right, we have another woman, a schoolteacher, who came to us and wanted to become pregnant. She is 26 years of age, and you can see the main pulmonary artery. This is a difficult angiogram; she has a mechanical tricuspid valve, we are across that valve shooting an angiogram, and it is sort of a negative image. Here is the main pulmonary artery; here are the branch pulmonary arteries; and with a cardiac MRI, you can see how small these pulmonary arteries are, off to the left and to the right. Again, these are very difficult lesions to treat and to deal with, but very common in our population.

In terms of vascular lesions, here is an atrial-switch patient, detransposition, Mustard operation. SVC comes down and goes into the heart, and we frequently see stenosis at this level. This doesn't seem like a concerning level of stenosis, but again, most of these patients with transposition atrial switch require pacemaker placement. We place pacemaker wires through this and eventually these areas will obstruct with 2 or 3 wires going through this area. On the right, we see a more concerning look at SVC stenosis, actually probably complete obstruction here, with collateral vessels and a patient in which a pacemaker lead was pulled out and then couldn't be placed back in again.

Valvular heart disease is also very common, probably the most common form of valvular heart disease that we see is in a patient with TOF, in which they have had a complete repair.

Most of our patients with TOF, status post repair, do have pulmonary insufficiency, and this is just showing on a lateral projection, severe pulmonary insufficiency.

Residual shunts, again, can be common in our patient populations.

Unfortunately, this was a young m an in his 20s, who presented to us with cyanosis and had a stroke. This is the SVC baffle limb of an atrial baffle, and again this blue blood should only go this way, toward these pacemaker leads, out to the morphologic left ventricle, but there is a huge baffle leak here, It is not uncommon to see leaks in our patients. On the right is a patient with a Fontan who has a lateral tunnel, again a leak where the blue blood is going into the systemic circulation; he is at high risk for cyanosis, high risk for having thromboembolic disease, and then finally, heart failure.

We see all forms of heart failure.

This is a patient with TOF. Patients with TOF who have undergone repair, have pulmonary insufficiency and, with cardiac MRI, we can get exquisite views of the right ventricle and measure right-ventricular size and systolic function. This is a young girl who is only 23 years old who came to us with palpitations and heart failure symptoms and has reduced right-ventricular systolic function from pulmonary insufficiency; we should be aware of this and treat this.

On the right we have another young man, also in his 20s, who has double-outlet right ventricle, and has severe systolic dysfunction of his single ventricle, with an ejection fraction of only about 10% to 15%. He fortunately was able to undergo a heart transplant about 4 or 5 months ago and is doing well now.

Finally, pulmonary hypertension is within this group.

The CONCOR study looked at the prevalence of pulmonary hypertension in these particular groups. They found about 6% of those patients in this large registry of about 5000 patients had pulmonary hypertension. The highest prevalence was in AVSD. About 10% to 15% of ASDs and VSDs will have pulmonary hypertension. These are all adult patients who will have pulmonary hypertension, 10% to 15% of those, single-ventricle patients. The right-ventricle patients have again about 30% incidence, in this particular database.

Here is an AVSD, in terms of an anatomic picture, and it has both an ASD and a VSD, and a common AV valve. This is just showing traditional left to right shunting that would occur. As time goes on, the patient can reverse the shunt and go right to left and become cyanotic with this lesion.

In this large registry of patients, focusing just on pulmonary hypertension, it is about 5000, almost 6000 patients actually from this European database. Before, I was showing you the main diagnostics, but overall for their entire group, it was about 4.2%, and 1% of those had Eisenmenger syndrome; 10% of those are considered at risk, and at risk would be those with septal defects, those with single ventricles, surgical shunts, and truncus arteriosis, and again 10% of those would be the risky lesions, who have pulmonary hypertension. That's a high proportion of patients in a database of 5000 patients.

There were 1824 patients in the septal-defect group, 6% incidence; half of those, or more than half of those, had Eisenmenger's syndrome. The mean age for that 6% was about 38, so again, they are young patients. VSD was the most common defect, by far, but the highest prevalence was the AVSD group at 41%. Almost half of the them had pulmonary hypertension as an adult.

This is just another way of looking at it. The VSDs were the highest group of patients, in terms of population, but if you look at prevalence overall, in terms of prevalence of pulmonary hypertension, the highest was in patients with VSDs and ASDs -- around 10% for this population.

In summary for the ACHD population, we now expect that about 90% of those with CHD will survive to adulthood. It is an expanding population and appears to be exceeding those pediatric patients with CHD. Once the patients reach adulthood, their survival is not what we would expect. Obviously we have an opportunity to do something about this, and we should continue to work with this. They have residual anatomic and physiologic abnormalities, which that we just demonstrated, and we need to be proactive in our approach to these patients with our medical therapies; we should treat heart failure aggressively, employ interventional therapy, and place implantable cardioverter-defibrillators (ICDs) when indicated, go to the cath lab and fix these lesions, and then perform surgical therapies when they are indicated. We need to improve the long-term outcome for the patients.

Although we can see this as not being what we expect, there are opportunities to improve the care of our adult patients with CHD.