Balloon coarctation angioplasty in adolescents and adults: early and intermediate results

Small-Diameter Stents in Cardiovascular Applications

Small-diameter stents play a crucial role in treating congenital heart diseases and variety of vascular conditions that have application from paediatrics to geriatric conditions, and a comprehensive review in this direction is lacking. This review explores historical development, design innovations, material compositions and mechanistic insights into functions of small-diameter stents, with a specific emphasis on biodegradable options. The necessity for stents that can adapt to growth of paediatric patients is discussed, highlighting the transition from durable polymers to bioresorbable materials such as polylactic acid (PLA) and magnesium alloys. While acknowledging the advancements made in reducing complications like restenosis and thrombosis, the review addresses the challenges that persist, including the need for improved biocompatibility and minimization of late adverse cardiac events associated with certain stent technologies. A detailed examination of various stent generations emphasizes the importance of drug release kinetics, structural integrity and potential for personalized interventions based on patient-specific factors. The exploration of novel therapeutic compounds, including nanoparticles and interfering RNA, illustrates the ongoing research aimed at enhancing stent efficacy. Ultimately, the review seeks to provide a comprehensive understanding of current landscape while identifying the gaps that future research must address to develop the ideal stent for diverse patient populations.

Immediate results of percutaneous management of coarctation of the aorta: A 7-year single-centre experience

BACKGROUND

Coarctation of the aorta (CoA) is often treated percutaneously. The aim of this study was to describe the immediate results of percutaneous management of native aortic coarctation (NaCoA) and recoarctation of the aorta (ReCoA) at our institution.

METHODS

We identified all patients with NaCoA or ReCoA who underwent percutaneous dilatation by either balloon angioplasty (BAP) or endovascular stent implantation (ESI) between 2011 and 2017. Success was defined as a residual peak-to-peak gradient (PPG) <20 mmHg or a ≥50% reduction in the gradient if the pre-intervention PPG was <20 mmHg.

RESULTS

63 patients (median age 6.8 years, interquartile range [IQR] 0.4-14.2) were identified. Among 11 patients with NaCoA, 7 underwent BAP and 4 had ESI, and among 52 patients with ReCoA, 42 underwent BAP and 10 had ESI. In patients with NaCoA, BAP was successful in 71%, with median PPG decreasing from 32 mmHg (IQR 25-46) to 17 mmHg (IQR 4-23) (p = .02), and ESI was successful in 100%, with median PPG decreasing from 20 mmHg (IQR 14.5-40) to 2 mmHg (IQR 0-6) (p < .01). In patients with ReCoA, BAP was successful in 69%, with median PPG decreasing from 20 mmHg (IQR 16-31.3) to 9 mmHg (IQR 0-14.3) (p < .001), and ESI was successful in 100%, with median PPG decreasing from 18 mmHg (IQR 11.5-22.8) to 0 mmHg (IQR 0-3.5) (p < .01). ESI was more successful than BAP (p = .01). There was only one complication.

CONCLUSIONS

Percutaneous management of CoA is safe and effective in both NaCoA and ReCoA. Stent implantation is more effective than BAP.

Endovascular Techniques in Adult Aortic Coarctation: The Use of Stents for Native and Recurrent Coarctation Repair

Purpose:

To report initial experiences with stent implantation in the treatment of native and recurrent aortic coarctation in adults.

Methods:

Two adult patients were diagnosed with aortic coarctation: in one, the native aorta was involved, and in the other, the stenosis involved a prior coarctation repair. Both patients were offered and selected angioplasty with possible stent implantation as an alternative to surgery.

Results:

In the patient with recurrent narrowing, thrombolysis and balloon dilation preceded the successful deployment of three Palmaz stents along the grafted segment. In the case of native disease, one Palmaz stent was implanted primarily at the site of a critical, focal stenosis. No complications were encountered, and recovery was uneventful. Follow-up at 12 and 6 months, respectively, showed sustained clinical improvement with resolution of symptoms and excellent hemodynamic values.

Conclusion:

The positive outcome in these early cases supports further evaluation of the efficacy of adjunctive or primary stenting for treatment of native or recurrent aortic coarctation in adults.

Recurrent coarctation: interventional techniques and results

Coarctation of the aorta (CoA) accounts for 5% to 8% of all congenital heart defects. With all forms of interventions for native CoA, repeat intervention may be required due to restenosis and/or aneurysm formation. Restenosis rates vary from 5% to 24% and are higher in infants and children and in those with arch hypoplasia. Although repeat surgery can be done for recurrent CoA, guidelines from a number of professional societies have recommended balloon angioplasty with or without stenting as the preferred intervention for patients with isolated recoarctation. For infants and young children with recurrent coarctation, balloon angioplasty has been shown to be safe and effective with low incidence of complications. However, the rates of restenosis and reinterventions are high with balloon angioplasty alone. Endovascular stent placement is indicated, either electively in adults or as a bailout procedure in those who develop a complication such as dissection or intimal tear after balloon angioplasty. Conventionally bare metal stents are used; these can be dilated later if required. Covered stents, introduced more recently, are best reserved for those who have aneurysm at the site of previous repair or who develop a complication such as aortic wall perforation or tear. Stents produce complete abolition of gradients across the coarct segment in a majority of cases with good opening of the lumen on angiography. The long-term results are better than that of balloon angioplasty alone, with very low rates of restenosis. However, endovascular stenting is a technically demanding procedure and can be associated with serious complications rarely.

Stents in paediatric and adult congenital interventional cardiac catheterization

A 'stent' is a tubular meshed endoprosthesis that has contributed to the development of interventional catheterization over the past 30 years. In congenital heart diseases, stents have offered new solutions to the treatment of congenital vessel stenosis or postsurgical lesions, to maintain or close shunt patency, and to allow transcatheter valve replacement. First, stents were made of bare metal. Then, stent frameworks evolved to achieve a better compromise between radial strength and flexibility. However, almost all stents used currently in children have not been approved for vascular lesions in children and are therefore used 'off-label'. Furthermore, the inability of stents to follow natural vessel growth still limits their use in low-weight children and infants. Recently, bioresorbable stents have been manufactured and may overcome this issue; they are made from materials that may dissolve or be absorbed in the body. In this review, we aim to describe the history of stent development, the technical characteristics of stents used currently, the clinical applications and results, and the latest technological developments and perspectives in paediatric and adult congenital cardiac catheterization.

The unusual hypertensive patient

Many young patients with systemic hypertension have secondary causes which if identified early could lessen the cardiovascular complications associated with long standing hypertension. Coarctation of the aorta is one of those rare causes. We describe a 40 year old male with hypertension, coarctation of the aorta, bicuspid aortic valve, PDA and an adrenal mass.

Endovascular management of recurrent adult coarctation of the aorta

Traditional open surgical repair has proven to be an effective treatment for the management of primary and recurrent coarctation of the thoracic aorta. Potential complications at short-term and long-term follow-up have included recurrent coarctation, hypertension, premature coronary artery disease, cerebrovascular disease, and anastomotic pseudoaneurysm. Endovascular repair of recurrent coarctation of the thoracic aorta offers a less invasive treatment approach in potential high-risk surgical patients.

Stent implantation for coarctation of the aorta in children <30 kg

OBJECTIVES

Our aim was to determine key characteristics of stents commonly implanted in the aorta through bench testing and to describe our technique and acute results in patients weighing <30 kg.

BACKGROUND

Despite the increasing use of stents for interventional treatment for coarctation of the aorta (CoA) in larger patients, use of large stents is controversial in small children.

METHODS

Methods included bench testing of large stents, and retrospective review of all patients over 1 year of age who had stent implantation for treatment of CoA. Patients were divided into 2 groups based on weight. Paired comparisons were made before and after stent implantation, and group outcomes were compared.

RESULTS

Sixty patients comprised the entire sample, with 22 patients assigned to group I (<30 kg) and 38 patients assigned to group II (>or=30 kg). The mean minimum diameters of the CoA (group I 5.0 to 10.7 mm; group II 8.0 to 15.0 mm) and the ratio of the coarctation diameter to the descending aorta diameter measured at the level of the diaphragm (CoA/DAo ratio) (group I 0.4 to 0.93; group II 0.46 to 0.94) increased significantly in both groups (all p < 0.05). The mean systolic gradient decreased significantly in both groups (group I 23.0 to 2.0 mm Hg; group II 24.0 to 2.8 mm Hg; both p = 0.001). No difference was found between the groups in the CoA/DAo ratio, residual systolic gradients, or the decrease in systolic gradient after stent implantation. There were no significant complications in patients under 30 kg.

CONCLUSIONS

As in larger patients, use of large stents for treatment of CoA in small children is effective and safe in the short term. In these patients, stent redilations will be required, and follow-up is ongoing.

Procedural results and acute complications in stenting native and recurrent coarctation of the aorta in patients over 4 years of age: a multi-institutional study

BACKGROUND

We report a multi-institutional experience with intravascular stenting (IS) for treatment of coarctation of the aorta.

METHODS AND RESULTS

Data was collected retrospectively by review of medical records from 17 institutions. The data was broken down to prior to 2002 and after 2002 for further analysis. A total of 565 procedures were performed with a median age of 15 years (mean=18.1 years). Successful reduction in the post stent gradient (<20 mm Hg) or increase in post stent coarctation to descending aorta (DAo) ratio of >0.8 was achieved in 97.9% of procedures. There was significant improvement (P<0.01) in pre versus post stent coarctation dimensions (7.4 mm+/-3.0 mm vs. 14.3+/-3.2 mm), systolic gradient (31.6 mm Hg+/-16.0 mm Hg vs. 2.7 mm Hg+/-4.2 mm Hg) and ratio of the coarctation segment to the DAo (0.43+/-0.17 vs. 0.85+/-0.15). Acute complications were encountered in 81/565 (14.3%) procedures. There were two procedure related deaths. Aortic wall complications included: aneurysm formation (n=6), intimal tears (n=8), and dissections (n=9). The risk of aortic dissection increased significantly in patients over the age of 40 years. Technical complications included stent migration (n=28), and balloon rupture (n=13). Peripheral vascular complications included cerebral vascular accidents (CVA) (n=4), peripheral emboli (n=1), and significant access arterial injury (n=13). Older age was significantly associated with occurrence of CVAs. A significant decrease in the technical complication rate from 16.3% to 6.1% (P<0.001) was observed in procedures performed after January 2002.

CONCLUSIONS

Stent placement for coarctation of aorta is an effective treatment option, though it remains a technically challenging procedure. Technical and aortic complications have decreased over the past 3 years due to, in part, improvement in balloon and stent design. Improvement in our ability to assess aortic wall compliance is essential prior to placement of ISs in older patients with coarctation of the aorta.

Coarctation of the aorta

Coarctation of the aorta is an important, treatable cause of secondary hypertension. Its prevalence varies from 5% to 8% of all congenital heart defects. This condition is most often detected because of a murmur or hypertension found on routine examination. Delayed or absent femoral pulses and an arm/leg systolic blood pressure difference of 20 mm Hg or more in favor of the arms may be considered as evidence for aortic coarctation. The coarctation may be demonstrated on a suprasternal notch two-dimensional echocardiographic view along with increased Doppler flow velocities across the coarctation site. Cardiac catheterization reveals significant systolic pressure gradient (> 20 mm Hg) across the coarctation and angiography demonstrates the degree and type of aortic narrowing. Aortic obstruction may be relieved by surgery or by transcatheter techniques; the latter include balloon angioplasty and stent implantation. In the past, surgery has been used exclusively, but because of morbidity and complications associated with surgery, catheter techniques are increasingly used in the management of aortic coarctation. Balloon angioplasty in children and stents in adolescents and adults are becoming initial therapeutic options for management of coarctation. Studies evaluating long-term follow-up results of the interventional techniques are needed.

Stenting vs. balloon angioplasty for discrete unoperated coarctation of the aorta in adolescents and adults

More information is needed to clarify whether stenting is superior to balloon angioplasty (BA) for unoperated coarctation of the aorta (CoA). From September 1997, 21 consecutive adolescents and adults (24 +/- 11 years) with discrete CoA underwent stenting (G1). The results were compared to those achieved by BA performed in historical group of 15 patients (18 +/- 10 years; P = 0.103; G2). After the procedure, systolic gradient reduction was higher (99% +/- 2% vs. 87% +/- 17%; P = 0.015), residual gradients lower (0.4 +/- 1.4 vs. 5.9 +/- 7.9 mm Hg; P = 0.019), gain at the CoA site higher (333% +/- 172% vs. 190% +/- 104%; P = 0.007), and CoA diameter larger (16.9 +/- 2.9 vs. 12.9 +/- 3.2 mm; P < 0.001) in G1. Aortic wall abnormalities were found in eight patients in G2 (53%) and in one in G1 (7%; P < 0.001). There was no major complication. Repeat catheterization (n = 33) and/or MRI (n = 2) was performed at a median follow-up of 1.0 year for G1 and 1.5 for G2 (P = 0.005). Gradient reduction persisted in both groups, although higher late gradients were seen in G2 (median of 0 mm Hg for G1 vs. 3 for G2; P = 0.014). CoA diameter showed no late loss in G1 and a late gain in G2 with a trend to being larger in G1 (16.7 +/- 2.9 vs. 14.6 +/- 3.9 mm; P = 0.075). Two patients required late stenting due to aneurysm formation or stent fracture in G1. Aortic wall abnormalities did not progress and one patient required redilation in G2. Blood pressure was similar in both groups at follow-up (126 +/- 12/81 +/- 11 for G1 vs. 120 +/- 15/80 +/- 10 mm Hg for G2; P = 0.149 and 0.975, respectively). Although satisfactory and similar clinical outcomes were observed with both techniques, stenting was a better means to relieve the stenosis and minimize the risk of developing immediate aortic wall abnormalities.

Initial experience using the NuMED Cheatham Platinum (CP) stent for interventional treatment of coarctation of the aorta in children and adolescents

We report the immediate results in a group of selected patients with native or recurrent coarctation of the aorta who underwent endovascular stent implantation using the newly designed Cheatham-Platinum (CP)-stent. The balloon-expandable stents were implanted in 6 patients (mean age 12.7 years) with coarctation of the aorta (5 native, 1 recurrent). The maximal systolic peak pressure gradient was decreased from 49 to 3 mmHg (p <0.001). There was a 350% increase in the mean diameter at the original coarctation site (3.8 to 13.8 mm, p <0.01). Although the maximal diameter varied from 8 to 18 mm, there was only a minor reduction in the length of the CP-stents used (max. 11%). The dilatation was successful in all patients and there were no complications during balloon dilatation or stent implantation. All patients were hypertensive prior to stent implantation, with three of them requiring antihypertensive drug therapy. In 2 patients only a moderate dilatation diameter was chosen initially due to the extremely small coarctation site (1 mm) and repeat dilatation after 12 months was performed in order to obtain a maximal aortic diameter. At a mean of 18 months of follow-up, 5 of 6 patients are normotensive. There is no recurrence of coarctation, aortic dissection or aneurysm formation and no stent displacement. These findings suggest that the implantation of CP-stents for coarctation of the aortamay cover a wide spectrum of aortic diameters and consequently hereby offer an effective alternative approach to surgery or ballon dilatation alone even in infancy and childhood. The potential for redilatation of CP-stents in a wide range of diameters without significant shortening adds to the benefit of this device in growing children.

Long-term outcome (up to 15 years) of balloon angioplasty of discrete native coarctation of the aorta in adolescents and adults

OBJECTIVES

This study evaluated the long-term follow-up results of balloon angioplasty (BA) in adolescent and adult patients with discrete coarctation of the aorta.

BACKGROUND

Although the immediate and intermediate term results of BA for patients with aortic coarctation (AC) have been encouraging, there is a paucity of data on long-term follow-up results.

METHODS

This basis of this study was follow-up of 49 patients (mean age, 22 +/- 7 years) undergoing BA for discrete AC at median interval of 10.2 years, including cardiac catheterization, magnetic resonance imaging, and Doppler echocardiography.

RESULTS

No early or late deaths occurred. Balloon angioplasty produced a reduction in peak AC gradient from 66 +/- 23 mm Hg (95% confidence interval [CI]: 59.5 to 72.7) to 10.8 +/- 7 mm Hg (95% CI: 8.8 to 12.5) (p < 0.0001). Follow-up catheterization 12 months later revealed a residual gradient of 6.2 +/- 6 mm Hg (95% CI: 4.4 to 7.9) (p < 0.001). Four patients (7.5%) with suboptimal initial outcome with peak gradient >20 mm Hg had successful repeat angioplasty. Aneurysm developed at the site of dilation in four patients (7.5%). Magnetic resonance imaging follow-up results revealed no new aneurysm or appreciable changes in the size of pre-existing aneurysms, and no recoarctation was observed. Also, no appreciable changes in the Doppler gradient across the AC site were noted. The blood pressure had normalized without medication in 31 (63%) of the 49 patients.

CONCLUSIONS

Long-term results of BA for discrete AC are excellent and should be considered as first option for treatment of this disease.

The adult patient with native coarctation of the aorta: balloon angioplasty or primary stenting?

OBJECTIVE

To compare results of dilatation of native coarctation of the aorta with and without stent implantation.

DESIGN

Open, observational, non-randomised study.

PATIENTS

54 consecutive adult patients: 32 with balloon angioplasty alone (group 1) and 22 with stent placement (group 2).

INTERVENTIONS

Balloon dilatation from 1995 to 1997; dilatation with Palmaz stent placement from 1997 to 1999.

MAIN OUTCOME MEASURES

The primary end point was a composite index of failure including heart related death, a residual gradient of > 20 mm Hg, the need of reintervention, and aneurysm formation.

RESULTS

Peak systolic gradient (mean (SD)) was reduced both in group 1 (from 63.3 (22.8) to 10.7 (10.8) mm Hg, p < 0.001) and group 2 (from 63.9 (20.8) to 2.7 (4.3) mm Hg, p < 0.001), but Delta change was significantly greater in group 2. A residual gradient of > 10 mm Hg was shown to be the best cut off point to separate risk groups, representing a hazard ratio (HR) of 9.59 compared with a residual gradient of < or = 10 mm Hg (95% confidence interval (CI) 1.92 to 47.8). From multivariate Cox regression analysis, the only risk marker was the residual gradient (HR 8.9, 95% CI 1.2 to 63.0). The type of the coarctation and the use of stent were the factors associated with a residual gradient of < or = 10 mm Hg.

CONCLUSIONS

Mid term outcome in adult patients with native aortic coarctation receiving percutaneous treatment is strongly related to the immediate residual gradient. When treating these cases, efforts should be made to obtain gradients under 10 mm Hg, either by angioplasty alone or by placing a stent. Patients with discrete aortic coarctation have similar mid term results when the immediate residual gradient is < or = 10 mm Hg despite the implantation of a stent. To achieve these gradients, patients with hypoplastic isthmus or tubular coarctation should be treated with primary stenting. Further studies including exercise tests and non-invasive imaging are still needed before definitive conclusions can be drawn.

Angioplasty for coarctation in different aged patients

BACKGROUND

Differences in the indication and outcome of balloon angioplasty for coarctation in children and adults have not been elucidated sufficiently. The results of balloon angioplasty for coarctation are compared between pediatric and adult age groups.

METHODS

Balloon angioplasty for coarctation of the aorta was performed in 85 patients who were classified according to age and native coarctation/recoarctation. Groups A (patients aged <16 years, n = 32) and B (patients aged > or =16 years, n = 17) included patients with native coarctations. Groups rCoA A (patients aged <16 years, n = 33) and rCoA B (patients aged > or =16 years, n = 3) included patients with recoarctations. Follow-up included 2-dimensional Doppler scanning echocardiography and additional angiography or magnetic resonance imaging. Gradient reductions in groups were compared by use of the independent-samples t test. Kaplan-Meier and log-rank analyses were performed as a means of comparing long-term outcome.

RESULTS

No mortality occurred. Immediate success was equal in groups A, B, and rCoA A (94%). Dilatation was unsuccessful in 2 patients in group rCoA B. Pressure gradients decreased 23 mm Hg in group A, 31 mm Hg in group B, 18 mm Hg in group rCoA A, and 11 mm Hg in group rCoA B. Pressure gradient drops, compared between groups A and B, showed a significant difference (P <.001). The length of hospital stay ranged from 12 to 48 hours. The period of follow-up ranged from 6 months to 12 years (mean, 4.9 years). Kaplan-Meier curves of groups A and B are not different, as determined by means of log-rank analysis. No aneurysm formation was encountered.

CONCLUSIONS

The results of balloon angioplasty for native coarctation in both selected children and adults are excellent. In recoarctation, we recommend balloon angioplasty in the pediatric patients.

Percutaneous recanalization and balloon angioplasty of congenital isolated local atresia of the aortic isthmus in adults

Congenital isolated local atresia of the aortic isthmus is anatomically similar and morphogenetically related to congenital coarctation of the aorta and was encountered in 4 out of 26 consecutive adult patients selected for coarctation angioplasty at our center. Anterograde recanalization of the atresia was safely and successfully accomplished in all four patients, using a brachial approach. Balloon dilation in the four patients, with ancillary stent implantation in one patient, resulted in reduction of translesion gradient from 84 +/- 11 mm Hg to 9 +/- 7 mm Hg without complications. Angiography in the three non-stented patients after a mean follow-up of 13 months showed no evidence of restenosis, dissection or aneurysm formation, though one patient had mild dilatation of the posterior aspect of the aortic isthmus. The clinical presentation of patients with isolated local aortic atresia, and their short- to mid-term response to percutaneous treatment, is similar to that of patients with isolated severe coarctation of aorta.

Endovascular stents in the management of coarctation of the aorta in the adolescent and adult: one year follow up

OBJECTIVES

To test the hypothesis that endovascular stents used with dilation of coarctation of the aorta (CoA) improve late outcomes. Balloon dilation for CoA has been limited by concerns over the risk for acute dissection, late restenosis, or aneurysm formation.

DESIGN

All patients seen with CoA between November 1994 and September 1997 underwent attempted stent implantation. Follow up was obtained for all patients and a subgroup (n = 18) had repeat catheterisation at a mean (SD) of 1.3 (0.5) years to assess residual gradient and stent-CoA morphology.

RESULTS

Stents were placed in 27 patients (15 male and 12 female patients, mean age 30.1 (13.1) years), of whom seven had prior surgical coarctectomy and one had a prior balloon dilation. Hypertension was present in 26 patients (mean pressure 164 (26)/86 (13) mm Hg), of whom 16 were on antihypertension drugs. CoA gradients were 46 (20) mm Hg (range 18-106 mm Hg) at baseline and 3 (5) mm Hg after the procedure. One patient had a stroke following the procedure; another patient had incomplete dilation and underwent a second procedure. At 1.8 (1) years after the procedure the mean pressure was 130 (14)/74 (11) mm Hg with seven patients on antihypertension treatment. The clinical gradient was 4 (8) mm Hg (range 0-32 mm Hg). At follow up angiography, the mean gradient was 4(6) mm Hg, and two patients had a gradient over 10 mm Hg. Aneurysms formed in three patients at the dilation site; one patient was referred for surgery.

CONCLUSION

In this age group stent management for CoA appears to be an effective technique and results in sustained reduction in CoA gradients at early term follow up, but aortic aneurysm was detected in 17% of patients who had repeat angiography.

Endovascular stents in the management of coarctation of the aorta in the adolescent and adult: one year follow up

OBJECTIVES

To test the hypothesis that endovascular stents used with dilation of coarctation of the aorta (CoA) improve late outcomes. Balloon dilation for CoA has been limited by concerns over the risk for acute dissection, late restenosis, or aneurysm formation.

DESIGN

All patients seen with CoA between November 1994 and September 1997 underwent attempted stent implantation. Follow up was obtained for all patients and a subgroup (n = 18) had repeat catheterisation at a mean (SD) of 1.3 (0.5) years to assess residual gradient and stent-CoA morphology.

RESULTS

Stents were placed in 27 patients (15 male and 12 female patients, mean age 30.1 (13.1) years), of whom seven had prior surgical coarctectomy and one had a prior balloon dilation. Hypertension was present in 26 patients (mean pressure 164 (26)/86 (13) mm Hg), of whom 16 were on antihypertension drugs. CoA gradients were 46 (20) mm Hg (range 18–106 mm Hg) at baseline and 3 (5) mm Hg after the procedure. One patient had a stroke following the procedure; another patient had incomplete dilation and underwent a second procedure. At 1.8 (1) years after the procedure the mean pressure was 130 (14)/74 (11) mm Hg with seven patients on antihypertension treatment. The clinical gradient was 4 (8) mm Hg (range 0–32 mm Hg). At follow up angiography, the mean gradient was 4(6) mm Hg, and two patients had a gradient over 10 mm Hg. Aneurysms formed in three patients at the dilation site; one patient was referred for surgery.

CONCLUSION

In this age group stent management for CoA appears to be an effective technique and results in sustained reduction in CoA gradients at early term follow up, but aortic aneurysm was detected in 17% of patients who had repeat angiography.

Balloon angioplasty of coarctation of the aorta: a safe alternative for surgery in adults: immediate and mid-term results

Patients with coarctation of the aorta can be treated either with surgery or with balloon angioplasty. So far, the last method has proved to be successful in children, but results of this treatment in (young) adults are virtually unknown. The aim of this study was to evaluate the immediate and mid-term follow-up results of balloon angioplasty of native coarctation in (mainly young) adults. Coarctation of the aorta was diagnosed by means of ultrasound or angiography, and defined as a stenosis with a pressure gradient greater than 20 mm Hg. The balloon angioplasty-procedure was carried out under complete anesthesia, and was considered to be successful, if the pressure gradient was reduced to less than 20 mm Hg. Nineteen consecutive adults (12 males, 7 females; aged 14-67 years, median 29) with native coarctation were treated from 1995-99. Mean pressure gradient decreased from 49.3+/- 20.8 to 4.8+/-8.2 mm Hg (P<0.0001). One patient showed a suboptimal result with a residual pressure gradient of 28 mm Hg. In one other patient a stent was placed on request of the referring physician. Follow-up was 100% complete and ranged from 3-47 months (mean 20.2+/- 12.9). At 1-year follow-up mean systolic blood pressure was reduced from 159.4+/-19.5 to 132.5+/-17.6 mm Hg (n = 18; P<0.0001), and mean ankle-arm pressure index improved from 0.73+/-0.09 to 0.96+/-0.05 (n = 18; P<0.0001). Anti-hypertensive medication could either be reduced or stopped in 7 patients (53.8%). With ultrasound or angiography or MRI, no patients had signs of aneurysm formation or worsening restenosis during follow-up. In adult patients with uncomplicated native coarctation of the aorta, balloon angioplasty (without stenting) would seem to be an excellent and safe alternative for surgery. In our hospital it has completely replaced surgical correction in such patients.

Coarctation of the Aorta

Balloon angioplasty or early surgical correction is recommended once coarctation of the aorta has been diagnosed. Medical management is not a long-term option. The rate of restenosis is higher in infants and children than in adults, but the incidence of residual or late hypertension increases with age at initial intervention. Current angioplasty and stent placement techniques have reduced the rate of aneurysm formation and expanded the types of complex anatomic configurations amenable to nonsurgical intervention. Patients require long-term follow-up for restenosis and late or residual hypertension. Coarctation treatment is straightforward in patients with simple isolated coarctation. In neonates with associated lesions and diffuse arch hypoplasia, aggressive (albeit higher-risk) arch-enlargement procedures can be done at the time of open-heart correction of intracardiac defects. Changes in aortic compliance, vascular reactivity, and vascular homeostasis mechanisms in patients who have late surgery are associated with a higher incidence of residual hypertension.

Middle aortic syndrome treated by stent implantation

OBJECTIVES

To determine outcome of stent implantation in patients with middle aortic syndrome.

DESIGN

Prospective study, case series.

SETTING

A tertiary paediatric cardiology centre in a children's hospital.

PATIENTS

Five patients, aged 4 to 17 years (mean 11.4 years), with upper limb hypertension due to middle aortic syndrome.

INTERVENTION

Stents were implanted in the mid/lower thoracic/upper abdominal aorta.

MAIN OUTCOME MEASURE

Satisfactory deployment of stents and blood pressure control.

RESULTS

In all patients, angiocardiography showed long segment stenosis in the mid or lower thoracic/upper abdominal aorta. The pressure gradient was between 40 and 90 mm Hg (mean 63.2 mm Hg). Seven Palmaz stents were implanted. Immediately after implantation, the gradient decreased to between 0 and 35 mm Hg (mean 13.6 mm Hg). Angiography showed a satisfactory result with widely patent stents in all. In one patient, thrombosis of the stent occurred six days after implantation. This was successfully treated with infusion of alteplase, further balloon dilatation, and implantation of a second stent overlapping the first, both dilated to 10 mm diameter. One patient had elective redilatation of the stent six months after implantation, with further reduction of the gradient from 35 mm Hg to 10 mm Hg. At the latest follow up between three and 20 months (mean 12.2 months) after stent implantation, in four patients blood pressure was better controlled with antihypertensive drugs. One patient was normotensive without drugs. Computed tomography showed no aneurysm formation in the region of the stents.

CONCLUSIONS

Stent implantation is a preferable alternative to surgery in the treatment of patients with middle aortic syndrome and merits further evaluation.

One- to ten-year follow-up results of balloon angioplasty of native coarctation of the aorta in adolescents and adults

OBJECTIVES

We attempted to evaluate the role of balloon angioplasty in the treatment of discrete coarctation of the aorta in adolescents and adults, with special emphasis on long-term results.

BACKGROUND

Controversy persists over the use of balloon dilation for the treatment of native coarctation of the aorta.

METHODS

Between July 1986 and January 1997, 43 consecutive adolescent and adult patients with discrete coarctation of the aorta underwent balloon angioplasty. One- to 10-year follow-up data of 37 patients, including results of cardiac catheterization and magnetic resonance imaging (MRI), form the basis of this study.

RESULTS

No early or late deaths occurred. Balloon angioplasty produced a reduction in the peak to peak coarctation gradient from a mean +/- SD of 69 +/- 24 mm Hg (95% confidence interval [CI] 61 to 76) to 12 +/- 8 mm Hg (95% CI 10 to 14.8) (p < 0.001). Follow-up catheterization 12 months later (37 patients) revealed a residual gradient of 6.7 +/- 6 mm Hg (95% CI 4.6 to 8.9); 3 (7%) of 43 patients had suboptimal results with development of recoarctation, defined as peak gradient >20 mm Hg, with successful repeat angioplasty. A small aneurysm developed at the site of dilation in 3 (7%) of the 43 patients. MRI follow-up data 1 to 10.8 years (mean 5.2 +/- 2.7) after angioplasty (37 patients) revealed no new aneurysm or appreciable change in the size of the preexisting aneurysm in the three patients. The blood pressure had normalized without medication in 27 (73%) of 37 patients at follow-up examination.

CONCLUSIONS

Balloon angioplasty is safe and effective and should be considered a viable alternative to operation for treatment of discrete coarctation of the aorta in adolescents and adults.

Dilation mechanism, causes of restenosis and stenting in balloon coarctation angioplasty

This review focuses on the individual dilation mechanism, the possible cause of restenosis after balloon angioplasty and the clinical application of a stent in coarctation of the aorta. Balloon angioplasty is still not the first choice of therapy in neonates with native coarctation because of the potential risk of aortic disruption, the high incidence of restenosis and the satisfactory results of surgical coarctectomy. Intravascular ultrasound imaging provides the individual mechanism of aortic dilation by balloon, and this will be a new modality for assessing the relationship between restenosis and aortic luminal morphology after balloon dilation. Although the cause of restenosis after balloon angioplasty remains uncertain, it may be due to a combination of elastic recoil by ductal tissue constriction, intimal hyperplasia and arterial remodelling. A stent could be an effective alternative to conventional balloon angioplasty in native coarctation of the aorta, preventing ductal tissue constriction. However, the problematic relationship between patient growth and relative stenosis of the stent should be clarified before clinical application of a stent for this disease.

Acute results of balloon angioplasty of native coarctation versus recurrent aortic obstruction are equivalent. Valvuloplasty and Angioplasty of Congenital Anomalies (VACA) Registry Investigators

OBJECTIVES

This study sought to compare the immediate results and risk factors for suboptimal outcomes of percutaneous balloon angioplasty for native versus recurrent aortic obstruction.

BACKGROUND

Some cardiology centers have been reluctant to adopt balloon angioplasty for treatment of native aortic coarctation, while advocating balloon angioplasty over an operation for treatment of postsurgical or recurrent aortic obstruction.

METHODS

Acute results were analyzed from 970 procedures (422 native and 548 recurrent lesions) performed between 1982 and 1995 in 907 patients from 25 centers. An acute suboptimal outcome was defined as one or more of the following: residual systolic pressure gradient > or = 20 mm Hg, residual proximal to distal systolic pressure ration > or = 1.33 or a major complication (death, aortic transmural tear, stroke).

RESULTS

Bal loon angioplasty significantly (p = 0.0001) increased lesion diameter fo r both native (mean [+/= SD] 128 +/= 94%) and recurrent aortic obstruction (97 +/= 87%), with a significantly greater increase in the native group (p = 0.0001). A reduction in systolic pressure gradients was significant in both groups (p = 0.0001), but slightly higher (p = 0.01) for native (-74 +/- 24%) versus recurrent obstruction (-70 +/- 31%). Death associated with angioplasty was reported in 0.7% of patients with native and in 0.7% of patients with recurrent lesions (p = 1.00). An acute suboptimal outcome was noted with angioplasty in 19% of native and in 25% of recurrent lesions (p = 0.04). Significant independent risk factors included higher preangioplasty systolic gradient (odds ratio [OR] 1.39/10-mm Hg increment; 95% confidence interval [CI] 1.28 to 1.50, p = 0.0001), earlier study date (OR 0.92/1-year increment, 95% CI 1.02 to 1.26, p = 0.02) and recurrent obstruction (OR 1.39 vs. native lesions, 95% CI 1.00 to 1.94, p = 0.05).

CONCLUSIONS

Acute results and complications of balloon angioplasty of native coarctation appear to be equivalent or slightly superior to those of recurrent aortic obstructions.

Aortic coarctation: a rare and unexpected cause of secondary arterial hypertension in the elderly

We present a 72-year-old man with long-standing moderate hypertension, due to an aortic coarctation, who presented with a myocardial infarction. In view of his advanced age the aortic coarctation was treated conservatively.

Late development of dissecting aneurysm following balloon angioplasty of native aortic coarctation

Acute aortic dissection during balloon angioplasty for coarctation of the aorta or aneurysm formation during follow-up are well-known complications of this procedure. Dissecting aneurysm development during long-term follow-up after balloon angioplasty of a native coarctation has not been previously reported. We report a case in which a huge dissecting aneurysm developed 3 years after the native coarctation angioplasty procedure. The aneurysm required surgical repair.

Long-term effects of balloon coarctation angioplasty on arterial blood pressure in adolescent and adult patients

In patients with coarctation of the aorta arterial hypertension frequently persists when surgical repair is performed after age 20 years. There are little data on the long-term effect of angioplasty and the question remains to be determined whether hypertension is sufficiently treated by this procedure. Twenty-nine consecutive patients (9 females and 20 males) 14 to 54 years old (median, 25) underwent angioplasty for native coarctation of the aorta. Twenty-five patients (86%) had pre-existing systolic arterial hypertension (> 140 mm Hg). The mean peak systolic pressure gradient decreased from 62 +/- 18 to 21 +/- 13 mm Hg immediately after angioplasty. At hospital discharge 13 patients still had hypertension. After a mean follow-up interval of 4.0 years (range, 0.3-9.5) the residual peak pressure gradient was 14 +/- 13 mm Hg. Blood pressure was normal without antihypertensive therapy in 23 patients (79%). In the six hypertensive patients the pressure gradients were 7, 13, 30, 30, 35, and 60 mm Hg. One patient died 8 months after angioplasty and another underwent surgery for aortic aneurysm. Although this was an uncontrolled study the data suggest that normalization of blood pressure may occur more frequently after angioplasty than after surgery in adolescents and adults with native coarctation.

Balloon angioplasty for native coarctation of the aorta

Balloon angioplasty of native coarctations of the aorta is one of the most controversial facets of the pediatric interventional cardiologist's practice. We have evaluated the history and experimental rationale of this technology. Presently accepted techniques are outlined and controversies intrinsic in performance of this procedure are discussed. Acute, short-term, and long-term results are reviewed with particular emphasis on differences in success of the procedure as related to patient age. Common and significant complications are discussed and in some cases compared to analogous surgical complications. Newer technologies and approaches to interventional therapy for coarctation of the aorta are also discussed.

Endovascular techniques in adult aortic coarctation: the use of stents for native and recurrent coarctation repair

PURPOSE

To report initial experiences with stent implantation in the treatment of native and recurrent aortic coarctation in adults.

METHODS

Two adult patients were diagnosed with aortic coarctation: in one, the native aorta was involved, and in the other, the stenosis involved a prior coarctation repair. Both patients were offered and selected angioplasty with possible stent implantation as an alternative to surgery.

RESULTS

In the patient with recurrent narrowing, thrombolysis and balloon dilation preceded the successful deployment of three Palmaz stents along the grafted segment. In the case of native disease, one Palmaz stent was implanted primarily at the site of a critical, focal stenosis. No complications were encountered, and recovery was uneventful. Follow-up at 12 and 6 months, respectively, showed sustained clinical improvement with resolution of symptoms and excellent hemodynamic values.

CONCLUSIONS

The positive outcome in these early cases supports further evaluation of the efficacy of adjunctive or primary stenting for treatment of native or recurrent aortic coarctation in adults.

Balloon angioplasty of native coarctation of the aorta: midterm follow-up and prognostic factors

OBJECTIVES, This retrospective analysis was designed to examine the intermediate and long-term effects of balloon angioplasty for native coarctation of the aorta and to determine whether any factors are predictive of outcome.

BACKGROUND

Balloon angioplasty for native coarctation of the aorta is controversial. Concerns exist over lack of long-term follow-up and possible formation of aneurysms. The role of transverse arch and isthmus hypoplasia after balloon dilation is unknown.

METHODS

Included in the study were all patients 3 days to 29 years old (mean age 4.6 years) referred for possible balloon dilation to the pediatric cardiac catheterization laboratory with evidence of a discrete coarctation of the aorta. The hemodynamic data, angiograms and clinical records of 102 patients were examined, with follow-up data from 2 to 117 months (median 36.2) available in 92 patients.

RESULTS

Immediate success with balloon angioplasty was achieved in 93 (91.2%) of the 102 patients. Seventy-one patients (77.2%) with intermediate follow-up data (range 12 to 117 months) available are asymptomatic and normotensive, with insignificant arm to leg blood pressure gradients (< or = 20 mm Hg). Twenty-one patients (22.8%) with an initial successful result developed an increase in gradient 2 at 86 months after angioplasty, requiring reintervention in 18. Follow-up > 72 months is available in 17 patients, 16 of whom are normotensive and have not required additional intervention. No additional intervention was needed in 88.4% of older children and infants > 7 months old. Ten of the 13 surviving neonates who initially had a successful dilation required reangioplasty or operation 14 days to 10 months (median 4.6 months) after angioplasty. Transverse arch hypoplasia had minimal effect on follow-up blood pressure gradient, whereas isthmic hypoplasia was associated with reintervention in 50%. A small aneurysm was noted in 2 (1.9%) of 102 patients.

CONCLUSIONS

Balloon angioplasty of native aortic coarctation is effective in infants and older children. In neonates, balloon angioplasty provides effective palliation only. Aneurysm formation is rare; however, lifetime follow-up is warranted.

Balloon angioplasty with stent implantation in experimental coarctation of the aorta

BACKGROUND

Balloon angioplasty of coarctation of the aorta is an effective method of treatment but is complicated by tearing of the aortic intima, formation of aneurysms, and restenosis. Stent placement at the time of balloon dilation could prevent restenosis and could also prevent progression of intimal tears to aneurysms. The purpose of this study was to evaluate the feasibility of balloon dilation and implantation of balloon-expandable stents in an experimental model of coarctation and to examine the effect of stent placement at the site of surgically created stenosis.

METHODS AND RESULTS

Coarctation of the aorta was surgically produced in 11 juvenile swine. Simultaneous coarctation angioplasty and stent implantation was performed in 10 animals 34 +/- 7.8 days after surgery. Repeat catheterization was performed 59 +/- 6 days after stent implantation. Five animals underwent reexpansion of stents with subsequent follow-up catheterization. Aortic specimens were examined by light microscopy and scanning electron microscopy. Coarctation angioplasty with stent implantation was successful in all, with an increase in coarctation diameter from 46 +/- 8.5% to 90 +/- 12.2% of proximal aortic diameter (P = .0001). Systolic pressure gradient decreased from 32 +/- 19.8 to 0.5 +/- 2.8 mm Hg (P < .001). All stents were patent at follow-up catheterization, with no evidence of intraluminal thrombosis. Reexpansion in five animals increased the stent diameter from a mean of 77.4 +/- 12.1% to 93 +/- 11.0% of proximal aortic diameter (P = .02). Gross examination of aortic specimens demonstrated formation of neointima over the stent wherever the stent struts were in contact with the aortic wall. The stent occupied a subintimal position and produced minimal compression of the underlying media. Medial compression was noted immediately beneath stent struts, but there was no evidence of intimal or medial dissection.

CONCLUSIONS

Balloon angioplasty with simultaneous implantation of balloon-expandable stents is effective in relieving aortic obstruction in experimental coarctation. Reexpansion of the rigid stent can be performed in an area of surgical aortotomy and coarctation without significant intimal or medial injury. Stent implantation may be useful in preventing restenosis and aneurysm formation after angioplasty of coarctation.

Balloon angioplasty of a tissue conduit stenosis after surgical repair of anomalous left coronary artery

Surgical correction of anomalous coronary arteries may result in late conduit or anastamotic stenosis. In this case report, we describe the use of coronary angioplasty to dilate a stenosis at the aortic ostium of an intrapulmonary tunnel created to correct an anomalous left coronary artery from the pulmonary artery.

Magnetic resonance imaging compared with angiography in the evaluation of intermediate-term result of coarctation balloon angioplasty

Between July 1986 and December 1990, 24 consecutive adult patients with native coarctation of the aorta underwent balloon dilatation. Their ages ranged from 15 to 55 (mean 25) years. Dissection of the aorta developed in one patient. The remaining 23 patients were restudied by catheterization and magnetic resonance imaging (MRI) 8 to 60 (mean 21) months after dilatation. Both studies were performed between 1 and 180 (mean 40) days of each other. The diameter of the aorta at the site of previous coarctation was measured on angiogram and MRI by two independent observers. The data were compared by means of linear regression analysis. The gradient across the previous coarctation site ranged from 0 to 20 (mean 7 +/- 7.3) mm Hg. The diameter of the aorta at the site of previous coarctation measured on angiogram was 13.7 +/- 3.7 mm and on MRI it measured 13.5 +/- 3.7 mm, with excellent correlation (r = 0.96, SEE = 0.92, p < 0.001). Two patients had small aneurysms 2 cm in diameter demonstrated by angiography and MRI, and two patients developed restenosis, diagnosed correctly by both cardiac catheterization and MRI. This study demonstrates that MRI provides excellent visualization of the anatomy of the aorta and is a good noninvasive method for follow-up of patients undergoing balloon coarctation angioplasty.

Initial experience with balloon dilatation of supravalvar aortic stenosis

Primary balloon dilatation of supravalvar aortic stenosis was attempted in three patients: a 20 year old woman, a seven month old boy, and a 12 year old girl. Balloon catheters (Mansfield) with diameters of 25 mm, 8 mm, and 15 mm were used in the three patients respectively. The systolic pressure gradient across the aortic narrowing decreased considerably and the diameter of the constricted area increased significantly. Balloon dilatation was feasible and provided good immediate results and sustained relief of supravalvar aortic stenosis in these three patients. However, a larger study is needed to establish the place of this procedure in treatment.