Role of Percutaneous Interventions in Adult Congenital Heart Disease
Congenital heart disease (CHD) is a major public health problem that is largely underrecognized. Surgical and medical advances over the past decades have dramatically improved the once bleak prognosis of patients with CHD. Eighty-five percent of infants born with congenital anomalies can now expect to reach adulthood. The current estimates of the prevalence of adult CHD in North America is 0.9 million.1,2 According to a recent population-based study, there are now more adults with severe CHD than children.2 Adults with both operated and unoperated CHD present with complex problems requiring long-term and close follow-up. The American College of Cardiology and American Heart Association (ACC/AHA) recently came out with guidelines on the management of adults with congenital heart disease (ACHD).3 The percutaneous interventional approach is becoming increasingly recognized as an alternative to surgery for a wide range of CHDs. For adult cardiologists in clinical practice, it is extremely important to have a sound understanding of CHD and the role of percutaneous interventions in the management of these disorders.
Atrial Septal Defect. Incidence. Atrial septal defects (ASD) account for 6–10% of all CHDs, and is the most common congenital heart defect diagnosed in adulthood.4 There are four types of ASDs, the most common being the ostium secundum ASD that is located in the area of the fossa ovalis, and accounts for 75% of all ASDs. It occurs due to either excessive resorption of the septum primum or from deficient growth of the septum secundum. An ostium primum ASD is usually associated with a group of defects that originate from the absence of an atrioventricular septum. A sinus venosus-type ASD is situated high in the septum at the cardiac junction of the superior vena cava and is usually associated with partial anomalous pulmonary venous return. Coronary sinus ASDs are rare and arise from an opening of the wall with the left atrium, allowing for atrial shunting.5
Indications for closure. Patients with uncorrected ASDs can reach old age, but have been shown to have a shortened life expectancy.6 On the other hand, the survival rate of young patients who have undergone surgical closure of an ASD is comparable to an age-matched control population.7 Long-term studies with surgical correction have shown excellent outcomes, with low morbidity and mortality. However, the surgical approach is associated with perioperative complications, longer hospital stays, and time away from work. Percutaneous ASD closure has thus been offered as an alternative to surgical repair.
The ACC/AHA Committee on ACHD recently released recommendations on interventional or surgical closure of ASDs.3 The presence of an enlarged right atrium or ventricle is considered a Class I indication for closure, regardless of symptoms. In patients with ASD, left-to-right shunting causes volume overload of the right heart, leading to right ventricular dilatation and elevation of pulmonary artery pressure. This is usually seen when the ratio of pulmonary-to-systemic blood flow (Qp/Qs) is > 1.5.5,8 Brochu et al showed that in asymptomatic or mildly symptomatic adults, there was subnormal VO2 max, even with modest left-to-right shunting (Qp/Qs 1.2–2.0), and that percutaneous closure improves exercise capacity, hemodynamics and right ventricular dimensions after 6 months.9 The presence of paradoxical embolism, regardless of the ASD diameter or shunt severity, is a Class IIa indication for closure.3
Surgical closure is considered the standard of therapy for ostium primum, sinus venosus and coronary sinus ASDs. Percutaneous closure of secundum ASDs is considered acceptable if certain criteria are met, as listed in Table 1. Transesophageal echocardiography (TEE) with agitated saline provides most, if not all, of the information needed in the evaluation of an ASD. The ACC/AHA guidelines do not require diagnostic cardiac catheterization for uncomplicated ASDs in younger patients with adequate noninvasive imaging.
In patients with an ASD and advanced pulmonary hypertension, it is recommended that careful assessment be performed prior to closure of the defect, since it may be serving as a relief valve, and repairing it could result in further elevations in pulmonary pressures and a drop in cardiac output. One way to assess the feasibility of repair is through right heart catheterization and pulmonary vasodilator testing. Another method is to transiently occlude the defect with a balloon and to examine the effect on pulmonary and systemic pressures.8,10
Surgery versus percutaneous intervention. Several nonrandomized studies have compared percutaneous ASD closure to surgical repair. The largest concurrent, nonrandomized multicenter study was reported by Du et al.11 They followed a total of 614 patients with secundum ASDs, in which 442 were assigned to the device group and 154 to the surgical group. The procedural success rate (no significant residual shunt) was 95.7% for the former and 100% for the latter. Efficacy rates (defined as successful closure without major complications and without a need for surgical intervention) were not significantly different between the two groups on discharge (94.8% vs. 96.1%), at 12 months (98.5% vs. 100%) and after the 2-year study period (91.6% vs. 89.0%). However, the complication rate was statistically higher (24%) for the surgical group compared to the device group (7.2%), which was largely influenced by more pericardial effusion with or without tamponade in the surgical group (p
Several improvements have been made to ASD occluder devices, delivery systems and percutaneous techniques since they were first described in 1976.13 Currently, percutaneous closure of secundum ASDs is performed through a femoral venous approach. The defect is crossed with a multipurpose catheter and a sizing balloon is inflated across the septum to determine the diameter. The occlusion device is deployed with the help of TEE and fluoroscopy, and is unscrewed from its cable once in the desired position (Figure 1).
The most frequently implanted ASD devices are the CardioSEAL/STARflex devices (CS/SF) (NMT Inc., Boston, Massachusetts), the Amplatzer Septal Occluder (ASO) (AGA Medical Group, Golden Valley, Minnesota), and the Helex Septal Occluder (HSO) (W.L. Gore and Associates, Flagstaff, Arizona) (Figure 2). The self-centering CS/SF incorporates a self-adjusting flexible spring system so that it can automatically adjust to different shapes and locations of ASDs.14 Initial studies have shown procedural success in 92.5% of cases. Some criticisms of the device include a complicated implantation technique and an inability to close defects > 2.0 cm in diameter. A newer device, the ASO, was approved by the U.S. Food and Drug Administration (FDA) in 2003. A head-to-head comparison of the two devices was made by Butera et al in 274 patients with small-to-moderate (up to 18 mm) ASDs.15 They found that the procedure and fluoroscopy time was shorter in the ASO group. Residual shunting during the procedure and at discharge was significantly more frequent in the CS/SF group. At 1-, 12- and 24-month follow up, the CS/SF group still had higher rates of residual shunting, with ASO achieving 100% complete occlusion after 1 month. Similar success rates were observed by Masura et al in 151 patients using the ASO after a median follow up of 78 months.16 The use of the Helex device in comparison to surgical closure was reported by Jones et al, who showed similar closure success (98.1% vs. 100%) and clinical success after 12 months (91.7% vs. 83.7%; p
Clinical outcomes with percutaneous intervention. Several authors have reported their experiences with percutaneous closure of secundum ASDs in the past decade (Table 2). In most patients, a defect in the interatrial septum can be occluded by a single device. However, around 2% of cases may require several devices due to multiple or complex fenestrated defects.18 In a registry of 33 patients with large secundum ASDs (> 30 mm but
Cardiac perforation is a rare, life-threatening and often avoidable complication of transcatheter closure.21 Divekar et al noted that late perforations account for two-thirds of all reported events, with 1 occurring as many as 3 years after device implantation. It occurs predominantly in the antero-superior walls and the adjacent aorta.22
Ventricular Septal Defect. Incidence. After a bicuspid aortic valve, ventricular septal defects (VSD) are the most common form of CHD, accounting for 20% of all congenital heart abnormalities.23 However, in the adult population, VSD is a rare diagnosis, with the estimated prevalence being only 0.3 in 1000.1 This is because moderate- to large-sized VSDs are usually recognized in childhood due to clinical symptoms that require closure. On the other end of the spectrum, most small-sized VSDs remain asymptomatic in childhood, and 90% close spontaneously by 10 years of age.23 VSDs encountered initially in adulthood (age > 20 years) are unlikely to close spontaneously. They may be asymptomatic or present with left-heart volume overload, pulmonary hypertension, aortic regurgitation, cardiac arrhythmia or infective endocarditis.24 Anatomically, these defects are located either in the perimembranous (more common) or muscular part of the septum. Patients with atrioventricular canal defects or inlet VSDs rarely survive into adulthood due to severe symptoms and pulmonary hypertension.
Indications for VSD closure. According to the recently-published ACC/AHA Guidelines, Class I indications for VSD closure in adults include: i) hemodynamically significant shunt with Qp/Qs ≥ 2.0 and clinical evidence of left ventricular (LV) overload; and ii) a history of infective endocarditis.3,24–26 Closure of a VSD is considered reasonable (Class IIa) when the Qp/Qs is > 1.5 with: i) pulmonary artery pressure less than two-thirds of systemic pressure and pulmonary vascular resistance (PVR) less than two-thirds of systemic vascular resistance; or ii) in the presence of LV systolic or diastolic failure.
Surgery versus percutaneous intervention. Surgery has been the mainstay of treatment for congenital VSDs for many years. It has low operative mortality (
In the late 1990s, the Amplatzer VSD occluder device (AGA Medical) was developed to close muscular VSDs. It gained popularity due to better and more reproducible results than earlier devices.33 This device has 2 discs made of nitinol, a thermoelastic alloy, and is filled with polyester fabric that is secured to the discs to increase closing ability.34 It requires the presence of a good-sized septal rim (> 5 mm) for closure of muscular defects. This device is not well suited for closure of perimembranous VSDs due to close proximity to the aortic valve, leading to the risk of aortic valve obstruction. A new Amplatzer occluder device with asymmetric discs has been introduced subsequently to specifically close perimembranous VSDs, but is not yet FDA-approved.
Percutaneous closure of VSDs is usually performed under both echocardiographic and fluoroscopic guidance. The defect is crossed from the left ventricular side of the septum with a balloon-tipped catheter, snaring the guidewire in the pulmonary artery and externalizing it through the internal jugular or femoral vein to form an arteriovenous loop. Subsequently, a sheath is introduced across the defect, and device deployment is performed to close the defect without interference with adjacent intracardiac structures (especially with perimembranous VSDs due to their close proximity to the atrioventricular valves and conduction system) (Figure 3). Patients are discharged the next day on aspirin and endocarditis prophylaxis for 6 months. Early complications include the risk of complete heart block, especially with perimembranous VSD closure (1–6%), aortic or tricuspid regurgitation, device dislodgement, residual shunt, ventricular rupture, air embolism, hemolysis or death. Late complications are usually uncommon, although a few reports of late-onset heart block have been reported and may require close surveillance.
Clinical outcomes with percutaneous intervention. Early registry experience with percutaneous VSD closure has demonstrated a good safety and efficacy profile. In the U.S. multicenter Amplatzer Muscular Ventricular Septal Occluder registry, 83 procedures were performed in 75 patients with a median age of 1.4 years (mostly pediatric, but a few adults were included). Successful deployment occurred in 86.7%, the major complication rate was 10.7%, and procedural mortality was 2.7%. The closure rates were excellent at long term, increasing from 47.2% at 24 hours to 92.3% at 12 months.35 A single-center experience from Italy in 40 adult patients using the Amplatzer device (22 muscular and 18 perimembranous VSDs) also reported 100% procedural success and no mortality. The complication rate was 14.6%, and the most frequent complication was a rhythm abnormality.36
Butera et al from Italy also recently reported their experience in 104 patients with perimembranous VSDs using the Amplatzer device.37 The mean age at closure was 14 years (range 0.6–63 years). Successful device deployment was achieved in 96.2% cases, with no mortality. The total occlusion rate was 47% at completion of the procedure, rising to 84% at discharge and 99% during follow up. The most significant complication was CHB, which required pacemaker implantation in 6 patients (5.7%; 2 in the early phase and 4 during the follow up phase). A similar study by Fu et al evaluated 35 patients who underwent catheter-based closure of membranous VSDs. There was a successful closure rate of 96%, no mortality, and 3 patients had major complications (1 patient each with complete heart block, perihepatic bleeding and ruptured tricuspid valve chordae tendinae).38 The results are encouraging and comparable to surgical treatment, although long-term follow up is clearly needed.
Recent results from the U.S. CardioSEAL VSD Registry with high surgical risk VSD patients (due to associated medical conditions or high-risk anatomy, i.e., multiple VSDs, posterior apical VSD or failed prior surgical closure), described 55 patients from 18 centers between the ages of 5 days and 65 years. There was a procedural success rate of 92%.39 Thirty-three patients had multiple VSDs and 23 of them were closed with a single device, while 10 patients required 2 devices. There was a major adverse event rate of 8%, including a 6% explantation rate and a 3.7% device embolization rate. There was no procedural mortality, but 30-day mortality was 6.6%. These results were comparable to surgery in high-risk patients.39,40
Clinical experience with percutaneous VSD closure is increasing. Complications seem to be limited to the acute phase of the procedure, with no significant late events. Enough concerns are raised, however, to warrant a multicenter national trial to verify the safety and feasibility of perimembranous and muscular device closure with direct comparison to surgery in terms of mortality and morbidity.41 Surgery still remains the treatment of choice in patients with large defects, coexistent congenital anomalies requiring surgical correction and defects with close proximity to the aortic valve. In appropriately selected patients and with good operator experience, the initial results with percutaneous device closure have been excellent, and the future looks bright.
Patent Ductus Arteriosus. Patent ductus arteriosus (PDA) accounts for about 10% of all CHD and is the second most common congenital anomaly seen in adults.23 It presents in isolation in 75% of adults, unlike in children, where it is frequently associated with more complex heart defects.42 Large uncorrected PDAs can lead to pulmonary hypertension and an increased risk of bacterial endocarditis. Both of these are corrected with closure of the PDA. Giroud et al proposes routine closure of all PDAs, including small silent PDAs, due to the devastating effects of endocarditis and the low risk of interventions.43 The ACC/AHA guidelines strongly recommend closure of a PDA either percutaneously or surgically in the presence of left atrial and/or ventricular enlargement, if pulmonary hypertension is present, or in the presence of net left-to-right shunting. A history of prior endarteritis is also a Class I indication. However, these are largely based on expert opinion.3 Unless there are other defects that require a surgical approach, percutaneous closure is favored due to the high success and low complication rates. In adults, however, closure is not as straightforward as in children due to the occurrence of Eisenmenger syndrome or the presence of calcification of the PDA. Options for percutaneous closure include the use of Cook detachable coils (Cook Inc., Bloomington, Indiana) and occluder devices (Rashkind-type occluders, Amplatzer duct occluders) (Figure 4). Both types of devices have been used with good procedural success and low morbidity rates. The procedure may be performed using the venous approach under local anesthesia.
For small PDAs, coils are often adequate to close the defect. Multiple coils may be used to close a single defect. Patel et al reported their experience with 149 patients aged 2 months to 55 years who underwent attempted coil embolization. The procedure was successful in 146 patients with PDAs measuring 2–7 mm. Complications occurred in 9 patients, including coil migration in 6 patients, left pulmonary artery stenosis in 2 infants and loss of femoral pulse in 1 patient.44 In a purely adult cohort of 9 patients (age range 16–65 years), Pas et al showed that use of coil embolization and the Rashkind device results in excellent 24-hour closure rates by echocardiography in PDAs up to 6 mm in diameter.45
For moderate-to-large PDAs, the Amplatzer device has been more commonly used, with sizes available up to 14 mm in diameter. However, most of the experience with its use is in children.46–49 Chessa et al reported successful embolization in 32 patients with ages ranging from 18–68 years, 10 of whom received an Amplatzer occluder, with good procedural and 6-month follow-up success rates.48 According to the National Institute for Clinical Excellence in the United Kingdom, the total mortality rate for PDA closure is 1/2317, or 0.04%.43 Other rare late complications include hemolysis due to small high-velocity residual shunting and iatrogenic left pulmonary stenosis.50
Fenestrated Fontan. Children born with inadequate pulmonary flow due to tricuspid or pulmonic atresia or single-chamber physiology require surgical connection of venous return to the pulmonary arteries in an operation called the Fontan procedure. Total cavopulmonary conduits are widely used for extracardiac Fontan. The first phase involves the bidirectional Glenn procedure, which requires anastomosis of the superior vena cava (SVC) to the right pulmonary artery. The Fontan completion is then done by connecting the inferior vena cava (IVC) to the right pulmonary artery. A high conduit pressure may result from many factors, including pulmonary artery stenosis (if present), elevated pulmonary vascular resistance and increased left ventricular end-diastolic pressure. Fenestrations are surgically created between the systemic venous and pulmonary venous circulation, which tends to decrease the pressure and improve cardiac output at the expense of low systemic oxygen saturations.
When desaturation becomes a concern, closure of this shunt may be done surgically or using occluder devices designed for ASD closure. In a registry of 154 patients following successful fenestration occlusion with either the clamshell or the CardioSeal device, Goff et al reported improvement in hospitalization, reduction in the need for digoxin and diuretics and lower rates of decompensation and death.51
Closure of Atrial Baffle Leaks after the Mustard or Senning Operations. Patients with complete transposition of the great arteries have greatly benefited from the “atrial switch” operation, also known as the Mustard and Senning operation, which involves excision of the atrial septum and the creation of a pericardial “baffle” in the atria that directs systemic venous flow across the mitral valve into the left ventricle, and pulmonary venous blood across the tricuspid valve into the right ventricle.52 This procedure has allowed patients to survive well into adulthood. Approximately 25% of patients who have undergone atrial baffle repair have been shown to have baffle leak, but a large majority of these are not hemodynamically significant.53 About 1–2% will have shunts that are significant enough to require intervention. Most baffle leaks are at the suture line of the superior limb of the systemic venous baffle, and may be closed using a transcatheter approach.54 Apostolopoulou et al reported a case of successful closure of a 10–12 mm atrial baffle leak in a 25-year-old patient with significant shunting using the STARFlex device. Follow up at 10 months still showed no shunting and improvement in exercise tolerance.55
Pulmonary Arteriovenous Fistulae. Pulmonary arteriovenous fistulae (PAVFs) provide a direct communication between arterial and venous circulation. About 500 cases have been reported and roughly half were part of hereditary generalized angiomatosis or Rendu-Osler-Weber disease.56 Patients with PAVFs experience shortness of breath, easy fatigability and cyanosis. Since these conduits bypass the capillary bed, they may also lead to stroke and brain abscesses. Percutaneous closure using the Amplatzer Duct Occluder was described by Bialkowski et al in 5 patients with a diameter range of 7–14 mm. They reported 100% procedural success with improved oxygen saturation and no major complications.57 For larger PAVFs (up to 45 mm), the Amplatzer Vascular Plug may be an option.58
Coarctation of the Aorta. Coarctation of the aorta (CoA) accounts for about 8% of all congenital defects. Discrete coarctation consists of short-segment narrowing at the area ligamentum arteriosum adjacent to the origin of the left subclavian artery. In adults, it is usually discovered during a workup for secondary systemic hypertension. Clinical examination reveals a radial-femoral pulse delay and differential systolic blood pressure between brachial and popliteal pressures of at least 10 mmHg.5 Doppler echocardiography of the descending aorta is also a useful noninvasive screening method. A resting peak velocity of ≥ 3.2 m/sec or diastolic velocity of ≥ 1.0 m/sec suggests significant coarctation.42 Magnetic resonance imaging has become the preferred imaging modality both for diagnosis and surveillance after correction.
Intervention for coarctation is recommended by the ACC/AHA guidelines in the following circumstances: i) a peak-to-peak coarctation gradient ≥ 20 mmHg; or ii) a peak-to-peak coarctation gradient
Surgical options for aortic coarctation include: resection with end-to-end anastomosis, prosthetic patch aortoplasty and interposition (tube bypass) grafting. Percutaneous angioplasty has been performed since 1982, but this has been associated with significant recoarctation.59 Balloon angioplasty produces a controlled injury of the intima and part of the media, increasing the vessel diameter and healing by fibrous scar. Suboptimal results due to hypoplasia or elastic recoil, restenosis and late aneurysm formation limited the long-term efficacy of angioplasty alone. The use of stents has improved outcomes due to the mechanical stability they provide and the prevention of recoil, making percutaneous intervention the procedure of choice for both native and recoarctation in patients > 6 years of age.42,60
Stent implantation for aortic coarctation is the second most frequently used procedure after ASD/PFO closure in a report on 40 patients by Chessa et al. After the procedure, the systolic peak pressure gradient dropped from 33.3 ± 13.5 to 3.1 ± 5 mmHg. In a report on 40 patients with coarctation, Chessa et al showed that stent implantation causes the systolic peak pressure gradient to drop post procedure from 33.3 ± 13.5 to 3.1 ± 5 mmHg. The diameter of the coarcted segment increased from 7.9 ± 3.1 mm to 15.7 ± 3.3 mm. Exercise testing after 6 months revealed hypertension in 8 patients (20%), with 5 having a nonsignificant transisthmus gradient (14 ± 5 mmHg).48 In some cases, there is a need for stent redilation due to recoarctation and recurrence of a gradient. In the same series, 3 patients (7.5%) required stent redilation as early as 13 months after the initial procedure.
Post-coarctation aneurysms occur after the performance of angioplasty for native coarctation. In their 21-year experience, Suarez De Lezo et al reports that the rate of late aneurysm formation was 6%.60 This complication appears less of a problem with the wider use of stents.61 Once an aneurysm has formed, a covered stent may be implanted. A potentially fatal complication is post-procedure aortic rupture. Two separate studies reported 1 death each (2.5% and 1.7%) due to this complication. Minor complications included a periaortic hematoma (2.5%) that was seen after stent implantation, but was absent on follow up, and femoral pseudoaneurysm requiring vascular surgical correction (5%).48
Post-Tetralogy of Fallot Repair. Tetralogy of Fallot (TOF) consists of subpulmonary infundibular stenosis, a VSD, an aorta that overrides the VSD, and right ventricular hypertrophy.5 The pulmonary valve is often small and stenotic. Pulmonary artery hypoplasia is frequent and may involve the pulmonary trunk or the branch pulmonary arteries, causing significant stenosis. The presence of TOF may be associated with other congenital defects such as secundum ASD, atrioventricular septal defect and a right aortic arch. Coronary artery anomalies also occur, most commonly with a left anterior descending coronary artery arising from the right coronary artery and crossing the right ventricular outflow tract (RVOT).
Unoperated patients are now rare in developed countries, except in immigrant populations. Surgical repair includes closure of the VSD, relief of RV outflow tract obstruction involving infundibular muscle resection, pulmonary valvotomy or valvectomy and commonly, RVOT augmentation with a subvalvular or transannular patch. The long-term outcome is excellent, with a survival rate of 86% at 30 years.62
The most common problem among adults who have undergone TOF repair is pulmonic regurgitation. Patients presenting with decreased exercise capacity should have a thorough evaluation with echocardiography. Other potential problems may be mechanical (tricuspid regurgitation, residual RVOT obstruction, branch pulmonary artery stenosis or hypoplasia) or electrical (ventricular tachycardia, atrioventricular block, atrial flutter/fibrillation, sudden cardiac death).
In patients who have undergone TOF repair and have unexplained LV or RV dysfunction, fluid retention, chest pain or cyanosis, the ACC/AHA gives a Class IIb recommendation to performing cardiac catheterization for possible transcatheter interventions. These interventions include: i) elimination of residual shunts or aortopulmonary collateral vessels (Level of Evidence [LOE]: C); ii) dilatation (with or without stent implantation) of the RVOT obstruction (LOE: B); iii) elimination of additional muscular or patch margin VSD (LOE: C); and iv) elimination of a residual ASD (LOE: B).3 In patients with severe pulmonic regurgitation and symptoms or signs of RV dysfunction, valve replacement surgery has a Class I indication. Percutaneous pulmonic valve implantation is a promising technique with good procedural and early success rates, but long-term data are still unavailable (see section on pulmonic stenosis).
Pulmonary Artery Stenosis. Pulmonary artery stenosis may result from an intrinsic abnormality in the pulmonary arteries as seen in CHDs like TOF, or may be a result of prior surgery such as shunt or arterial switch procedures. Percutaneous interventional therapy is recommended by the ACC/AHA as the treatment of choice in the management of appropriate focal branch and/or peripheral pulmonary artery stenosis with > 50% diameter narrowing, an elevated RV systolic pressure > 50 mmHg, and/or symptoms (LOE: B).3
Balloon angioplasty has been performed with modest success, showing a 50% increase in diameter in 64% of cases. However, the restenosis rate in this particular series was about 35% in early follow up.63 In a series of 200 patients, stent implantation was performed with early gradient reductions and increased vessel diameters.64 Medium-term follow up (average 14 months) showed minimal restenosis. Complications included death (1%), stent migration (2%), and stent thrombosis (1.5%).
Baffle Stenosis. Stenosis of systemic venous baffles after the Mustard operation occurs in 5–10% of patients. A study of 20 survivors of the Mustard procedure for TGA and with angiographically-proven baffle stenosis showed good procedural success with the balloon-expandable Palmaz stents. There was significant improvement in diameter and a decrease in the pressure gradient across the lesion.65 However, long-term follow-up data are still not available.
Valvular Heart Disease
Pulmonic Stenosis. Pulmonic stenosis (PS) is a common form of adult CHD, accounting for 10–12% of cases. Ninety percent of cases are due to valvular stenosis, which is related to commissural fusion of thin and pliable leaflets. Ten percent of cases are due to supravalvular PS (narrowing of pulmonary trunk, e.g., William’s syndrome) or subvalvular PS (infundibular stenosis that usually occurs in association with VSD).23 Most of the adults have asymptomatic mild PS (defined as a transvalvular gradient of 50 mmHg), however, become symptomatic with RV dysfunction, arrhythmia and sudden cardiac death. Sixty percent of these patients will need correction in the next 10 years. Even if the patients are asymptomatic, there is no benefit in delaying intervention.
Percutaneous balloon dilatation of the pulmonic valve is a safe and acceptable procedure to relieve obstruction from valvular PS.67 The results are comparable to surgery, have low morbidity and mortality, and most of these patients do not require any further procedures. The ACC/AHA guidelines give a Class I recommendation to balloon valvotomy for asymptomatic patients with a domed pulmonary valve and a peak instantaneous Doppler gradient > 60 mmHg or a mean Doppler gradient > 40 mmHg (in association with less-than-moderate pulmonic valve regurgitation) (LOE: B). In the presence of symptoms, a peak gradient of > 50 mmHg or a mean gradient of > 30 mmHg is also a Class I indication for balloon valvotomy (LOE: C). On the other hand, surgery is recommended for patients with severe PS and an associated hypoplastic pulmonary annulus, severe pulmonary regurgitation, subvalvular PS or supravalvular PS. Surgery is also preferred for most dysplastic pulmonary valves and when there is associated severe tricuspid regurgitation or the need for a surgical Maze procedure (LOE: C).3
Recently, late outcomes of patients who underwent pulmonic valve dilatation have reported that, similar to results with surgical valvotomy, late moderate or severe pulmonary regurgitation is increasingly recognized, and patient counseling and postprocedural surveillance are recommended.68
Percutaneous pulmonic valve implantation. Percutaneous pulmonary valve implantation (PPVI) has been one of the most fascinating recent developments in nonsurgical treatment of patients with dysfunction of the RVOT. A significant proportion of patients who undergo surgical correction of RV-to-pulmonary artery conduit obstruction in childhood present later in life with recurrent stenosis or regurgitation.69 This is associated with the development of RV failure, atrial or ventricular arrhythmias and sudden cardiac death. Though conduit stenosis can be treated with balloon dilatation, pulmonary regurgitation has conventionally required surgical correction. Thus, multiple operations are anticipated and performed in these adults with CHD. PPVI represents an important advance because it deals successfully with both the stenosis and regurgitation components of RVOT dysfunction.
The first successful human percutaneous implantation of a catheter-based stent valve was accomplished in the pulmonic position by Bonhoeffer in 2000. A bovine jugular vein valve was sutured onto a platinum stent and the stent-valve device was crimped on an 18 mm balloon catheter and enclosed within an 18 Fr sheath. The stent valve was delivered percutaneously via the femoral vein in a 12-year-old boy with a severely stenosed pulmonary valve in a RV-to-pulmonary artery conduit. Since then, further modifications have occurred in the design of percutaneous pulmonic valves.70 Two types of valves currently available for percutaneous implantation in the pulmonary position are the Melody valve (Medtronic) and the Edwards-Sapien transcatheter valve (same as the aortic valve). The Melody valve has been implanted in over 700 patients in more than 60 centers in Europe, Canada, Israel and Saudi Arabia. In the U.S., these valves are currently approved by the FDA only for investigational use (Figure 5).
The largest single-center experience of PPVI by Bonhoeffer et al included 155 patients who underwent this procedure from 2000 to 2007. Survival at 83 months was 96.9%. There was significant reduction in RV systolic pressure (from 63 ± 18 mmHg to 45 ± 13 mmHg; p
A recent report also examined the efficacy of repeat PPVI as a treatment modality for early device failure. Out of 173 percutaneous pulmonic valve implants, 20 patients had device failure in the early experience due to imperfect device design and stent fracture. Repeat PPVI provided an effective treatment for restenosis related to device failure and led to freedom from reintervention that was similar to rest of the cohort.72
These results are encouraging, and suggest that PPVI should reduce the number of operations and the cumulative hemodynamic burden on the RV over the total lifetime of children and young adults, potentially improving the life expectancy of patients with CHD that involves the RVOT.
Aortic Stenosis. Bicuspid aortic valve is the most common CHD, occurring in approximately 2% of the population. In infants and children, the stenosis is secondary to bicuspid commissural fusion. In this setting, balloon valvuloplasty may cause separation of the commissures, resulting in increased valve area, and consequently decreasing the transvalvular gradient. According to the ACC/AHA guidelines, as long as there are no significantly calcified aortic valves and no aortic regurgitation, aortic balloon valvotomy is indicated in the presence of: i) angina, syncope, dyspnea on exertion, and peak-to-peak gradients at catheterization > 50 mmHg; and ii) ST or T-wave abnormalities on electrocardiography at rest or with exercise and a peak-to-peak catheter gradient > 60 mmHg.3
In older adults, the presence of calcification causes poor tissue compliance making percutaneous intervention more difficult. A series of 165 studies involving percutaneous aortic valvuloplasty have shown dismal long-term clinical results after an average of 3.9 years of follow up.73 The ACC/AHA guidelines suggest that balloon valvotomy may be considered as a bridge to surgery in hemodynamically unstable adults with aortic stenosis, adults at high risk for aortic valve replacement (AVR), or when AVR cannot be performed secondary to significant comorbidities.3 Its current utility in adults is therefore limited to bridging and palliation.
Advances in device technology and improved outcomes have allowed more adults with CHD to pursue the option of percutaneous intervention. With further enrichment of clinical experience, procedural success rates and device safety are expected to improve in the future. However, some of the less common CHDs have limited availability of data on long-term outcomes, and pursuing percutaneous therapy should be done with an understanding of the potential risks and benefits. Data surveillance and reporting will play a crucial role in improving the quality of care of these patients. Percutaneous pulmonic valve implantation is one of the most fascinating recent developments in the management of patients with adult CHD. Appropriate patient selection and operator experience are keys to the success of catheter-based therapy in adult CHD.
1. Warnes CA, Liberthson R, Danielson GK, et al; Task force 1: The changing profile of congenital heart disease in adult life. J Am Coll Cardiol 200;3:1170–1105.
2. Marelli AJ, Mackie AS, Ionescu-Ittu R, et al. Congenital heart disease in the general population: Changing prevalence and age distribution. Circulation 2007;115:163–172.
3. Warnes CA, Williams RG, Bashore TM, et al. ACC/AHA 2008 guidelines for the management of adults with congenital heart disease. Circulation 2008, Nov 7 (Epub ahead of press).
4. Carlgren LE. The incidence of congenital heart disease in children born in Gothenburg 1941–1950. Br Heart J 1959;21:40–50.
5. Zipes DP. Braunwald’s Heart Disease: A Textbook of Cardiovascular Medicine. 7th ed. Vol. 2. 2005, Philadelphia: Elsevier, Inc., pp.1505–1506.
6. Campbell M. Natural history of atrial septal defect. Br Heart J 1970;32:820–826.
7. Murphy JG, Gersh BJ, McGoon MD, et al. Long-term outcome after surgical repair of isolated atrial septal defect. Follow-up at 27 to 32 years. N Engl J Med 1990;323:1645–1650.
8. Krasuski RA. When and how to fix a “hole in the heart”: Approach to ASD and PFO. Cleve Clin J Med 2007;74:137–147.
9. Brochu MC, Baril JF, Dore A, et al. Improvement in exercise capacity in asymptomatic and mildly symptomatic adults after atrial septal defect percutaneous closure. Circulation 2002;106:1821–1826.
10. de Lezo JS, Medina A, Romero M, et al. Effectiveness of percutaneous device occlusion for atrial septal defect in adult patients with pulmonary hypertension. Am Heart J 2002;144:877–880.
11. Du ZD, Hijazi ZM, Kleinman CS, et al. Comparison between transcatheter and surgical closure of secundum atrial septal defect in children and adults: Results of a multicenter nonrandomized trial. J Am Coll Cardiol 2002;39:1836–1844.
12. Durongpisitkul K, Soongswang J, Laohaprasitiporn D, et al. Comparison of atrial septal defect closure using Amplatzer septal occluder with surgery. Pediatr Cardiol 2002;23:36–40.
13. King TD, Thompson SL, Steiner C, Mills NL. Secundum atrial septal defect. Nonoperative closure during cardiac catheterization. JAMA 1976;235:2506–2509.
14. Budts W, Gewillig M, Van de Werf F. Left-to-right shunting in common congenital heart defects: Which patients are eligible for percutaneous interventions? Acta Cardiol 2003;58:199–205.
15. Butera G, Carminati M, Chessa M, et al. CardioSEAL/STARflex versus Amplatzer devices for percutaneous closure of small to moderate (up to 18 mm) atrial septal defects. Am Heart J 2004;148:507–510.
16. Masura J, Gavora P, Podnar T. Long-term outcome of transcatheter secundum-type atrial septal defect closure using Amplatzer septal occluders. J Am Coll Cardiol 2005;45:505–507.
17. Jones TK, Latson LA, Zahn E, et al. Results of the U.S. multicenter pivotal study of the HELEX septal occluder for percutaneous closure of secundum atrial septal defects. J Am Coll Cardiol 2007;49:2215–221.
18. Omeish A, Hijazi ZM. Transcatheter closure of atrial septal defects in children and adults using the Amplatzer Septal Occluder. J Interv Cardiol 2001;14:37–44.
19. Lopez K, Dalvi BV, Balzer D, et al. Transcatheter closure of large secundum atrial septal defects using the 40 mm Amplatzer septal occluder: Results of an international registry. Catheter Cardiovasc Interv 2005;66:580–584.
20. Post MC, Suttorp MJ, Jaarsma W, Plokker HW. Comparison of outcome and complications using different types of devices for percutaneous closure of a secundum atrial septal defect in adults: A single-center experience. Catheter Cardiovasc Interv 2006;67:438–443.
21. Chessa M, Carminati M, Butera G, et al. Early and late complications associated with transcatheter occlusion of secundum atrial septal defect. J Am Coll Cardiol 2002;39:1061–1065.
22. Divekar A, Gaamangwe T, Shaikh N, et al. Cardiac perforation after device closure of atrial septal defects with the Amplatzer septal occluder. J Am Coll Cardiol 2005;45:1213–1218.
23. Brickner ME, Hillis LD, Lange RA. Congenital heart disease in adults — First of two parts. N Engl J Med 2000;342:256–263.
24. Inglessis I, Landzberg MJ. Interventional catheterization in adult congenital heart disease. Circulation 2007;115:1622–1633.
25. Minette MS, Sahn DJ. Ventricular septal defects. Circulation 2006;114:2190–2197.
26. Gabriel HM. Long-term outcome of patients with ventricular septal defect considered not to require surgical closure during childhood. J Am Coll Cardiol 2002;39:1066–1071.
27. Bridges ND, Perry SB, Keane JF, et al. Preoperative transcatheter closure of congenital muscular ventricular septal defects. N Engl J Med 1991;324:1312–1317.
28. Bass JL, Kalra GS, Arora R, et al. Initial human experience with the Amplatzer perimembranous ventricular septal occluder device. Catheter Cardiovasc Interv 2003;58:238–245.
29. Sideris EB, Walsh KP, Haddad JL, et al. Occlusion of congenital ventricular septal defects by the buttoned device. “Buttoned device” Clinical Trials International Register. Heart 1997;77:276–279.
30. Kalra GS, Verma PK, Dhall A, et al. Transcatheter device closure of ventricular septal defects: Immediate results and intermediate-term follow-up. Am Heart J 1999;138(2 Pt 1):339–344.
31. Lock JE. Transcatheter closure of ventricular septal defects. Circulation 1988;78:361–368.
32. Knauth AL, Lock JE, Perry SB, et al. Transcatheter device closure of congenital and postoperative residual ventricular septal defects. Circulation 2004;110:501–507.
33. Carminati M, Butera G, Chessa M, et al. Transcatheter closure of congenital ventricular septal defect with Amplatzer septal occluders. Am J Cardiol 2005;96(12A):52L–58L.
34. Hijazi ZM, Hakim F, Al-Fadley F,, et al. Transcatheter closure of single muscular ventricular septal defects using the amplatzer muscular VSD occluder: Initial results and technical considerations. Catheter Cardiovasc Interv 2000;49:167–172.
35. Holzer R, Balzer D, Cao QL, et al. Device closure of muscular ventricular septal defects using the Amplatzer muscular ventricular septal defect occluder: Immediate and mid-term results of a U.S. registry. J Am Coll Cardiol 2004;43:1257–1263.
36. Chessa M, Butera G, Negura D, et al. Transcatheter closure of congenital ventricular septal defects in adult: Mid-term results and complications. Int J Cardiol 2008.
37. Butera G, Carminati M, Chessa M, et al. Transcatheter closure of perimembranous ventricular septal defects: Early and long-term results. J Am Coll Cardiol 2007;50:1189–1195.
38. Fu YC, Bass J, Amin Z, et al. Transcatheter closure of perimembranous ventricular septal defects using the new Amplatzer membranous VSD occluder: Results of the U.S. phase I trial. J Am Coll Cardiol 2006;47:319–325.
39. Lim DS, Forbes TJ, Rothman A, et al. Transcatheter closure of high-risk muscular ventricular septal defects with the CardioSEAL occluder: Initial report from the CardioSEAL VSD registry. Catheter Cardiovasc Interv 2007;70:740–744.
40. Kitagawa T, Durham LA 3rd, Mosca RS, Bove EL. Techniques and results in the management of multiple ventricular septal defects. J Thorac Cardiovasc Surg 1998;115:848–856.
41. Schmitz C, Esmailzadeh B, Herberg U, et al. Hybrid procedures can reduce the risk of congenital cardiovascular surgery. Eur J Cardiothorac Surg 2008;34:718–725.
42. Krasuski RA, Bashore TM. The emerging role of percutaneous intervention in adults with congenital heart disease. Rev Cardiovasc Med 2005;6:11–22.
43. Giroud JM, Jacobs JP. Evolution of strategies for management of the patent arterial duct. Cardiol Young 2007;17(Suppl 2):68–74.
44. Patel HT, Cao QL, Rhodes J, Hijazi ZM. Long-term outcome of transcatheter coil closure of small to large patent ductus arteriosus. Catheter Cardiovasc Interv 1999;47:457–461.
45. Pas D, et al. Persistent ductus arteriosus in the adult: Clinical features and percutaneous closure. Acta Cardiol 2002;57:275–78.
46. Faella HJ, Hijazi ZM. Closure of the patent ductus arteriosus with the amplatzer PDA device: Immediate results of the international clinical trial. Catheter Cardiovasc Interv 2000;51:50–54.
47. Bilkis AA, Alwi M, Hasri S, et al. The Amplatzer duct occluder: Experience in 209 patients. J Am Coll Cardiol 2001;37:258–261.
48. Chessa M, Carrozza M, Butera G, et al. The impact of interventional cardiology for the management of adults with congenital heart defects. Catheter Cardiovasc Interv 2006;67:258–264.
49. Santoro G, Bigazzi MC, Palladino MT, et al. Comparison of percutaneous closure of large patent ductus arteriosus by multiple coils versus the Amplatzer duct occluder device. Am J Cardiol 2004;94:252–255.
50. Presbitero P, Lisignoli V, Zavalloni D, et al. Endovascular intervention in the treatment of congenital heart disease in adults. Minerva Cardioangiol 2007;55:669–679.
51. Goff DA, Blume ED, Gauvreau K, et al. Clinical outcome of fenestrated Fontan patients after closure: The first 10 years. Circulation 2000;102:2094–2099.
52. Brickner ME, Hillis LD, Lange RA. Congenital heart disease in adults. Second of two parts. N Engl J Med 2000;342:334–342.
53. Park SC, Neches WH, Mathews RA, et al. Hemodynamic function after the Mustard operation for transposition of the great arteries. Am J Cardiol 1983;51:1514–1519.
54. Hornung TS, Benson LN, McLaughlin PR. Catheter interventions in adult patients with congenital heart disease. Curr Cardiol Rep 2002;4:54–62.
55. Apostolopoulou SC, Papagiannis J, Hausdorf G, Rammos S. Transcatheter occlusion of atrial baffle leak after mustard repair. Catheter Cardiovasc Interv 2000;51:305–307.
56. Burke CM, Raffin TA. Pulmonary arteriovenous malformations, aneurysms and reflections. Chest 1986;89:771–772.
57. Bialkowski J, Zabal C, Szkutnik M, et al. Percutaneous interventional closure of large pulmonary arteriovenous fistulas with the amplatzer duct occluder. Am J Cardiol 2005;96:127–129.
58. Ferro C, Rossi UG, Bovio G, et al. Percutaneous transcatheter embolization of a large pulmonary arteriovenous fistula with an Amplatzer vascular plug. Cardiovasc Intervent Radiol 2007;30:328–331.
59. Singer MI, Rowen M, Dorsey TJ. Transluminal aortic balloon angioplasty for coarctation of the aorta in the newborn. Am Heart J 1982;103:131–132.
60. Suárez de Lezo J, Pan M, Romero M, et al. Percutaneous interventions on severe coarctation of the aorta: A 21-year experience. Pediatr Cardiol 2005;26:176–189.
61. Piechaud JF. Stent implantation for coarctation in adults. J Interv Cardiol 2003;16:413–418.
62. Murphy JG, Gersh BJ, Mair DD, et al. Long-term outcome in patients undergoing surgical repair of tetralogy of Fallot. N Engl J Med 1993;329:593–599.
63. Bush DM, Hoffman TM, Del Rosario J, et al. Frequency of restenosis after balloon pulmonary arterioplasty and its causes. Am J Cardiol 2000;86:1205–1209.
64. Shaffer KM, Mullins CE, Grifka RG, et al. Intravascular stents in congenital heart disease: Short- and long-term results from a large single-center experience. J Am Coll Cardiol 1998;3:661–667.
65. Bu’Lock FA, Tometzki AJ, Kitchiner DJ, et al. Balloon expandable stents for systemic venous pathway stenosis late after Mustard’s operation. Heart 1998;79:225–229.
66. Hayes CJ, Gersony WM, Driscoll DJ, et al. Second natural history study of congenital heart defects. Results of treatment of patients with pulmonary valvar stenosis. Circulation 1993;87(2 Suppl):I28–I37.
67. Chen CR, Cheng TO, Huang T, et al. Percutaneous balloon valvuloplasty for pulmonic stenosis in adolescents and adults. N Engl J Med 1996;335:21–25.
68. Garty Y, Veldtman G, Lee K, Benson L. Late outcomes after pulmonary valve balloon dilatation in neonates, infants and children. J Invasive Cardiol 2005;17:318–322.
69. Khambadkone S, Coats L, Taylor A, et al. Percutaneous pulmonary valve implantation in humans: Results in 59 consecutive patients. Circulation 2005;112:1189–1197.
70. Feldman T, Leon MB. Prospects for percutaneous valve therapies. Circulation 2007;116:2866–2877.
71. Lurz P, Coats L, Khambadkone S, et al. Percutaneous pulmonary valve implantation: Impact of evolving technology and learning curve on clinical outcome. Circulation 2008;117:1964–1972.
72. Nordmeyer J, Coats L, Lurz P, et al. Percutaneous pulmonary valve-in-valve implantation: A successful treatment concept for early device failure. Eur Heart J 2008;29:810–815.
73. Lieberman EB, Bashore TM, Hermiller JB, et al. Balloon aortic valvuloplasty in adults: Failure of procedure to improve long-term survival. J Am Coll Cardiol 1995;26:1522–1528.
74. Hein R, Büscheck F, Fischer E, et al. Atrial and ventricular septal defects can safely be closed by percutaneous intervention. J Interv Cardiol 2005;18:515–522.
75. De Ridder S, Suttorp MJ, Ernst SM, et al. Percutaneous transcatheter closure of atrial septal defects: initial single-centre experience and follow-up results. Initial experience with three-dimensional echocardiography. Acta Cardiol 2005;60:171–178.
76. Egred M, Andron M, Albouaini K, et al. Percutaneous closure of patent foramen ovale and atrial septal defect: Procedure outcome and medium-term follow-up. J Interv Cardiol 2007;20:395–401.