Amplatzer patent foramen ovale occluder: safety and efficacy

Every Patent Foramen Ovale Should Be Closed

At present, the patent foramen ovale (PFO) does not receive the deserved medical attention. The PFO poses a serious threat to health and even the life of mankind. The first respective case report in the medical literature dates back to the 19th century. It led to death. The fact that a PFO is present in roughly 25% of people underscores its overall potential to cause harm. Yet at the same time, the sheer number discourages the medical community from screening for it and from treating it. About 5% of the population have particularly dangerous forms of PFOs. Such PFOs portray a high enough risk for clinical events, the likes of death, stroke, myocardial infarction, or ocular, visceral, and peripheral embolism, to justify screening for them. Highly significant health incidents being at stake, it appears obvious that PFO closure should be used for primary prevention. This is supported by the fact that closing a PFO is the simplest intervention in cardiology, with presumably the highest clinical yield. Being mainly a preventive measure, PFO closure represents a mechanical vaccination. When closing PFOs for one of the rarer therapeutic indications (migraine, platypnea orthodeoxia, etc.), patients automatically profit from the collateral benefit of getting, at the same time, mechanically vaccinated for life against paradoxical embolism. Vice versa, closing a PFO for the prevention of paradoxical embolism betters or cures migraine or exercise dyspnea not infrequently, thereby improving quality of life as a collateral benefit.

Comparison of the short-term efficacy of different Amplatzer models and similar occluders in the treatment of patent foramen ovale

Objective

To compare the recent efficacy and safety of different Amplatzer models and similar occluder in the treatment of patent foramen ovale (PFO).

Methods

Patients with PFO complicated with cryptogenic stroke or migraine who underwent transcatheter closure of PFO in the First Affiliated Hospital of Nanjing Medical University from September 2019 to March 2021 were selected. Patients were grouped according to the type of occluder device. The basic data of the patients were collected and followed up within 1 year after occlusion. Effectiveness was defined as no recurrence of stroke/remission of migraine symptoms and a negative postoperative foaming test, and safety events were counted as the combined results of serious adverse events.

Results

A total of 92 patients were selected, including 45 cases in the symmetrical group and 47 cases in the asymmetric group. There were no serious adverse events in the 2 groups during follow-up. 3 days and 1 month after occlusion, the number of shunt patients in the asymmetric group was significantly less than that in the symmetric group (χ² = 5.484, P = 0.019; χ² = 5.146, P = 0.023). The negative rate of blocked residual shunts in the asymmetric group was higher than that in the symmetric group at 1, 3, 6 and 12 months after occlusion (χ² = 6.473, P = 0.011; χ² = 4.305, P = 0.038; χ² = 4.842, P = 0.027; χ² = 4.034, P = 0.045). Headache in migraine patients in the asymmetric group was significantly better than headache in patients in the symmetric group (P = 0.038; P = 0.049).

Conclusion

Asymmetric Amplatzer and similar occluders provide greater efficacy in short-term occlusion than symmetric ones.

Outcomes of Patent Foramen Ovale Transcatheter Closure: Should a Short Aortic Rim Preclude Closure?

Background

The risk of erosion of an atrial septal closure device, in particular the Amplatzer Septal Occluder, has been described as higher in patients with a short aortic rim. Similar concern has been applied to patent foramen ovale (PFO) closure devices, but there are only rare reported cases of erosion. It may be that smaller devices are chosen due to fear of device erosion in PFO patients when this is not necessarily an issue.

Objectives

The authors aimed to assess outcomes after PFO closure with the Amplatzer PFO device in patients with a short (<9 mm) aortic rim.

Methods

We performed a retrospective analysis of PFO closure for any indication, between 2006 and 2017 at a quaternary center. Preprocedural transesophageal echocardiographic parameters including the aortic rim were remeasured. Long-term outcomes were obtained by linkage to provincial administrative databases.

Results

Over the study period, 324 patients underwent PFO closure with the Amplatzer PFO device, with a mean age of 49.8 years; 61% had a short aortic rim (<9 mm). The most common indication was cryptogenic stroke (72%); those with longer aortic distance were more likely to have a non-stroke indication for closure, diabetes (15% vs 6.5%, P = 0.04), and heart failure (15.7% vs 4%, P < 0.001). Over a median 7 years of follow-up, there were no cases of device erosion or embolization requiring cardiac surgery.

Conclusions

In a large cohort with long-term administrative follow-up (1,394 patient-years), implantation of an Amplatzer PFO device was performed safely even in patients with a short aortic rim.

Assessing patent foramen ovale on coronary computed tomographic angiography: a comparison with transesophageal echocardiography

PURPOSE

This study was undertaken to determine if coronary computed tomographic angiography (CCTA) can help to assess patent foramen ovale (PFO) with high accuracy and reproducibility when compared to transesophageal echocardiography (TEE).

MATERIALS AND METHODS

In total, 75 suspected PFO cases (31 men, 44 women; mean age, 45 ± 9 years) were evaluated by coronary CTA and TEE. PFO tunnel length (TL) and the opening diameter of the left atrial entrance (ODLAE) and right atrial entrance (ODRAE), as well as contrast shunt (if present due to PFO), were measured by both modalities.

RESULTS

PFO was detected in 68 patients with TEE. The sensitivity for the detection of PFO with CCTA was 85.3%; specificity, 71.4%; positive predictive value, 96.7%; and negative predictive value, 33.3%. Both modalities demonstrated good agreement in measuring TL and ODLAE of PFO. However, the ODRAE of TEE was different from that of CCTA (1.14 ± 0.4 mm and 1.45 ± 0.5 mm, respectively, p = 0.04). The intra-observer and inter-observer variability and agreement for TL, ODRAE, and ODLAE of PFO were excellent between the two measurements.

CONCLUSION

CCTA provided a method for detection of PFO with high accuracy and reproducibility compared with TEE. Therefore, CCTA is a practical and efficient alternative to TEE for PFO diagnosis.

Presence of a Septal Occluder Is No Longer an Obstacle for Pulmonary Vein Isolation by Cryoablation

Cryoablation for pulmonary vein isolation in atrial fibrillation has been considered a relative contraindication in the presence of a septal occluder device. We describe the successful conduct of this technique with a multimodality imaging approach.

Nickel Hypersensitivity to Atrial Septal Occluders: Smoke Without Fire?

Nickel is one of the most common contact allergens worldwide; it is used as the main component of the devices used for atrial septal defects (ASDs) and patent foramen ovale (PFO) closure. Developing nickel hypersensitivity after PFO/ASD occlusion is significantly rarer described in medical literature than typical nickel contact sensitization. The exact pathophysiological mechanism of this "device syndrome" remains unknown, and many question the real incidence or even the existence of this clinical entity. Nevertheless, it has been associated with a wide spectrum of symptoms, including chest pain, migraines, palpitation, and dyspnea. Skin patch tests are the first-line approach to diagnose nickel hypersensitivity. However, diagnostic criteria for the device syndrome have not been developed, and diagnosis in reported cases is established by a process of elimination. Management-drug therapy (corticosteroids, clopidogrel, etc.) or even surgical explantation in severe cases-of patients developing such clinical manifestations after percutaneous PFO/ASD occlusion is empirical. Undoubtedly, endocardiac device-related nickel hypersensitivity requires more focused research to discover the underlying mechanism as well as to develop reliable prognostic tests for detecting high-risk patients and preventing severe nickel hypersensitivity reactions.

Analytical methods for braided stents design and comparison with FEA

Braiding technology is nowadays commonly adopted to build stent-like devices. Indeed, these endoprostheses, thanks to their typical great flexibility and kinking resistance, find several applications in mini-invasive treatments, involving but not limiting to the cardiovascular field. The design process usually involves many efforts and long trial and error processes before identifying the best combination of manufacturing parameters. This paper aims to provide analytical tools to support the design and optimization phases: the developed equations, based on few geometrical parameters commonly used for describing braided stents and material stiffness, are easily implementable in a worksheet and allow predicting the radial rigidity of braided stents, also involving complex features such as multiple twists and looped ends, and the diameter variation range. Finite element simulations, previously validated with respect to experimental tests, were used as a comparator to prove the reliability of the analytical results. The illustrated tools can assess the impact of each selected parameter modification and are intended to guide the optimal selection of geometrical and mechanical stent proprieties to obtain the desired radial rigidity, deliverability (minimum diameter), and, if forming processes are planned to modify the shape of the stent, the required diameter variations (maximum and minimum diameters).

Antiplatelet and Antithrombotic Therapy After Patent Foramen Oval and Atrial Septal Defect Closure

Pathologies of the atrial septum include different interatrial communications varying from patent foramen ovale (PFO) to actual defects. Atrial septal defects (ASDs) may be localized within the fossa ovalis such as the secundum type ASD or outside the region of fossa ovalis, such as the ostium primum defect and sinus venosus defect. Over the last decades, the percutaneous closure of interatrial shunts has become a feasible and safe method. During these procedures, the delicate balance between thrombotic risk, device sealing process and bleeding risk is crucial. In this review, we sought to describe current available data on the antiplatelet and antithrombotic management of patients after percutaneous ASD or PFO closure.

Percutaneous Closure of Post-infarction and Iatrogenic Ventricular Septal Ruptures Using Amplatzer Occluder®: A Systematic Review

Ventricular septal rupture (VSR) is a rare complication of myocardial infarction (MI), open heart surgery, and cardiac-based procedures, such as septal myectomy and valve replacement. VSR is associated with high mortality rates and the reported 30-day survival rate is less than 10% without any interventional therapy. Hence, prompt diagnosis and aggressive medical treatment with appropriate surgical intervention are necessary to improve survival. Immediate surgical intervention which is the standard treatment of VSR has a mortality rate of 19-60%. Due to persistent high mortality rate and challenging management of VSR, alternatives to surgical repair has been proposed; transcatheter approach as a new alternative method has been used for the closure of post-surgery residual defects or as a bridge to surgery and in some cases as a definitive therapy instead of surgical repair. Amplatzer Occluder® (AO), a type of transcatheter closure devices, is an approved method of repairing congenital atrial septal defects and it is being used as an alternative method of treatment in VSR. In this systemic review, we assessed the cases of VSR who underwent septal repair by using AO. The study shows that the total mortality rate of percutaneous VSR repair with AO is 20% which is comparable to 19-60% rate of death in patients who undergo surgery. While early intervention is necessary to prevent biventricular dysfunction, immediate surgical intervention on soft and friable tissue surrounding the infarction increases the risk of residual shunt and reoperation. However, this study reveals that the mortality rate of primary percutaneous VSR closure within 7 days of VSR detection was 37 % which is significantly lower than 60% in surgical repair in the same period. In conclusion, given that the prevalence of residual leak in both interventions are similar and close to 20%, percutaneous VSR closure with AO device could be superior to the surgical repair as a primary intervention in unstable or high-risk surgical patients.

Network meta-analysis on patent foramen ovale: is a stroke or atrial fibrillation worse?

OBJECTIVE

Systematic reviews suggest that patent foramen ovale closure (PFOc) is performed percutaneously with low complication rates. We did a network meta-analysis (NMA) comparing devices for PFO closures, evaluating safety and efficacy of transcatheter PFOc in preventing neurological events in patients with stroke when compared with medical therapy (MT), and assessing risk of atrial fibrillation (AF).

METHODS

We searched 3 databases (MEDLINE, EMBASE, CENTRAL/CCTR) identifying six randomized controlled trials from 2012 until December 2019. We performed a Bayesian NMA; number-needed-to-treat and number-needed-to-harm were derived by applying the estimated odds ratios (ORs). The likelihood of being helped or harmed (LHH) was evaluated to estimate the risk-effectiveness balance.

RESULTS

The 3560 patients allocated to PFOc were less subject to a stroke than patients with MT. The overall ORs of PFOc versus MT were 0.41 with fixed-effects, and 0.22 with random-effects model. NMA proves that PFOc induces AF episodes significantly higher than MT, even when analysis is limited to only new episodes of "serious AF." LHH (0.68 fixed-effects, 0.79 random-effects) showed that strokes saved are less than cases of AFs added. By considering only serious AF, strokes saved are higher than serious AFs induced by the PFOc (LHH was 3.46 and 4.00 respectively).

CONCLUSIONS

NMA supported PFOc in patients with cryptogenic stroke, confirming that devices are better than MT, but increase the risk of AF by over 2/4 times (serious or unserious AF). Considering serious AFs (real risky clinical condition), patients have more advantages in being treated, since LHH is ≥ 3-4.

Percutaneous Closure of Patent Foramen Ovale in the Setting of Pulmonary Embolism (Right-Left Shunt Causing Severe Hypoxia)

A patent foramen ovale (PFO) is well known to cause paradoxical embolism and stroke, but a less appreciated and life-threatening complication can occur when combined with severe pulmonary embolism (PE). Acutely elevated right-sided pressures from right ventricular strain due to PE can lead to right-to-left (R-L) shunting through the PFO and exacerbate hypoxia. We report a case of a 50-year-old female patient with massive PE with further desaturation from R-L shunting from a PFO that benefitted from percutaneous closure of the interartrial communication. Our patient recovered without any complications and had excellent long-term follow-up.

Surgical management of embolized Amplatzer septal occluder into the left ventricle tangled with the mitral valve

Device embolization is a rare major complication of atrial septal defect percutaneous closures which requires surgical management if noninvasive retrieval fails. We report a symptomatic delayed embolization of an Amplatzer septal occluder device into the left ventricle outflow tract tangled with the mitral valve, complicated with ventricular arrhythmias and cardiac tamponade during percutaneous retrieval attempt. Emergent surgical treatment was performed, requiring a combined approach through the right atrium and the aorta for surgical removal.