Cerebral microembolism during transcatheter closure of patent foramen ovale

Cerebral Microemboli Detection and Differentiation During Transcatheter Closure of Patent Ductus Arteriosus

The aim of this prospective study was to determine the frequency and composition of cerebral microemboli in a pediatric population, during transcatheter closure of patent ductus arteriosus (PDA). Multifrequency transcranial Doppler was used to monitor cerebral blood flow velocity (CBFV) and detect microembolic signals (MES) in the middle cerebral artery in 23 patients (median age 18 months). MES were automatically identified and differentiated according to composition; gaseous or solid. The procedure was divided into five periods: Arterial catheterization; venous catheterization; ductal catheterization; angiography; device placement and release. Timing of catheter manipulations and MES were registered and compared. MES were detected in all patients. The median number of signals was 7, (minimum 1, maximum 28). Over 95 % of all MES were gaseous. 11 % were detected during device placement while 64 % were detected during angiographic studies, significantly higher than during any other period (P < 0.001). There was a moderate correlation between the number of MES and volume of contrast used, (R = 0.622, P < 0.01). There was no correlation with fluoroscopic time or duration of procedure. This is the first study to investigate the timing and composition of cerebral microemboli during PDA occlusion. Microemboli were related to specific catheter manipulations and correlated with the amount of contrast used.

Silent cerebral emboli following percutaneous closure of atrial septal defect in pediatric patients: a diffusion-weighted MRI study

PURPOSE

The aim of this prospective study was to investigate the incidence of silent cerebrovascular embolic events associated with percutaneous closure of atrial septal defect (ASD) in pediatric patients.

METHODS

A total of 23 consecutive pediatric patients (mean age, 10.4±3.8 years; range, 4-17 years) admitted for transcatheter closure of ASD were recruited in the study. The patients were scanned with a 1.5 Tesla clinical scanner. Two cranial magnetic resonance imaging (MRI) examinations were acquired before the procedure and within 24 hours following the catheterization. MRI included turbo spin-echo fluid-attenuated inversion recovery (FLAIR) sequence and diffusion-weighted imaging technique with single-shot echo-planar spin-echo sequence. The transcatheter closure of ASD was performed by three expert interventional cardiologists. Amplatzer septal occluder device was implemented for the closure of the defect. No contrast medium was administered in the course of the procedure.

RESULTS

None of the patients had diffusion restricted cerebral lesions resembling microembolic infarctions on postprocedural MRI. Preprocedural MRI of two patients revealed nonspecific hyperintense white matter lesions on FLAIR images with increased diffusion, which were considered to be older ischemic lesions associated with previously occurred paradoxical embolism.

CONCLUSION

The current study suggests that percutaneous closure of the ASD, when performed by experienced hands, may be free of cerebral microembolization in pediatric patients. However, due to the relatively small sample size, further studies with larger patient groups are needed for the validation of our preliminary results.

Cerebral microemboli detection and differentiation during transcatheter closure of atrial septal defect in a paediatric population

INTRODUCTION

The aim of this prospective study was to determine the frequency and composition of cerebral microemboli in a paediatric population during transcatheter atrial septal defect closure.

METHODS

Multi-frequency transcranial Doppler was used to detect microembolic signals in the middle cerebral artery of 24 patients. Embolic signals were automatically identified and differentiated according to their composition, gaseous or solid. The procedure was divided into five periods: right cardiac catheterisation; left cardiac catheterisation; pulmonary angiography; balloon sizing; and device placement.

RESULTS

Microemboli were detected in all patients. The median number of signals was 63 and over 95% gaseous. The total number of microembolic signals detected during two periods - balloon sizing and sheath placement and device placement - was not significantly different (median: 18 and 25, respectively) but was significantly higher than each of the other three periods (p<0.001). In eight patients, the device was opened more than once and the number of embolic signals decreased with each successive device deployment. There was no correlation between the number of microembolic signals and fluoroscopic time, duration of procedure, age, or device size.

CONCLUSION

This is the first study to investigate the timing and composition of cerebral microemboli in a paediatric population during cardiac catheterisation. Microembolic signals were related to specific catheter manipulations but were not associated with fluoroscopic time or duration of procedure.

Migraine attacks after transcatheter closure of atrial septal defect

Objective

The purpose of our study was to evaluate the effect of atrial septal defect (ASD) closure on migraine headache attacks (MHA).

Methods

A total of 247 patients who underwent percutaneous ASD closure at our facilities were sent a structured questionnaire. We diagnosed MHA according to the criteria of the International Headache Society.

Results

A total of 207 patients were included in the study. New-onset MHA occurred in 23 patients and persisted in 15 at a mean follow-up of 45 months. Of the 29 patients who had MHA prior to ASD closure, 11 reported exacerbation of MHA, 11 reported no change and seven reported improvement within three months after ASD closure. Compared with the patients who had no MHA, patients with de novo MHA were younger and patients with MHA improvement tended to be older. Switching from aspirin to ticlopidine or clopidogrel rapidly aborted frequent MHA in nine patients who had severe symptoms after ASD closure.

Conclusions

These results indicate that Amplatzer device implantation can act as a permanent trigger of MHA in not a few patients, and that age may be an important predictive factor of the influence of ASD closure on MHA.

Microembolic signals measured by transcranial Doppler during transcatheter closure of atrial septal defect using the Amplatzer septal occluder

PURPOSE

To determine the frequency and factors associated with increase in microembolic signals during transcatheter closure of atrial septal defect using the Amplatzer septal occluder.

METHODS

During the procedure in 16 patients, we measured microembolic signals using transcranial Doppler. Procedure time was divided into five periods: right cardiac catheterisation; left cardiac catheterisation; left cardiac angiocardiography; sizing and long sheath placement; device placement and release. We compared numbers of microembolic signals among the five periods and identified factors associated with them.

RESULTS

Mean size of septal occluder was 16 millimetres in diameter. Total number of microembolic signals was a median of 31.5, ranging from 3 to 113. Microembolic signals in three periods, left cardiac catheterisation; sizing, and long sheath placement; and device placement and release, were not significantly different from one another, but were significantly higher than those in the remaining two periods, right cardiac catheterisation and left cardiac angiocardiography (median was 9 in left cardiac catheterisation; 6 in sizing and long sheath placement; 6.5 in device placement and release, versus 0 in right cardiac catheterisation and 1 in left cardiac angiocardiography, p less than 0.05, respectively). Importantly, the time for device manipulation positively correlated with total number of microembolic signals (r equals 0.77, p less than 0.001), although fluoroscopic time, age, or size of septal occluder did not.

CONCLUSIONS

Transcatheter closure of atrial septal defect using the Amplatzer septal occluder produces microemboli, especially during device placement. To minimise the risk of systemic embolism, we must decrease the time for device manipulation.

Evolution of surgical techniques for atrial septal defect repair in adults: A 10-year single-institution experience

OBJECTIVE

We retrospectively analyzed our experience in atrial septal defect repair with varied minimally invasive surgical approaches.

METHODS

From 1997 to 2006, 64 patients underwent surgical repair of atrial septal defects in our center. Patients were grouped into four groups according to the approach used; group 1 (n = 16), partial lower sternotomy; group 2 (n = 20), right anterior small thoracotomy with transthoracic clamping; group 3 (n = 4), right anterior small thoracotomy with endoaortic balloon clamping; and group 4 (n = 24), totally endoscopic approach with the use of the da Vinci surgical system (Intuitive Surgical, Mountain View, Calif). Preoperative diagnosis was a large secundum type atrial septal defect in 60 patients, primum type in 3 patients, and sinus venosus type in 1 patient.

RESULTS

Complete atrial septal defect closure was verified by intraoperative transesophageal echocardiography in all patients. There was neither perioperative mortality nor major complication. Groups 3 and 4 had significantly longer aortic crossclamp, cardiopulmonary bypass, and skin-to-skin operative times than had groups 1 and 2 (P = .000). All groups had similar ventilation time, postoperative drainage, and intensive care unit and hospital stays. Only 2 patients in group 4 were converted to the minithoracotomy owing to endoaortic balloon failure. During the follow-up of 30 +/- 24.3 months, 1 patient in group 3 was reoperated on owing to significant residual shunting.

CONCLUSIONS

All types of atrial septal defects can be repaired via those four different approaches as safely as can be done by the conventional technique. General complications during surgical procedures are negligible. These approaches may be considered a standard treatment and an adjunct to transcatheter treatment options in atrial septal defect repair.

Patent foramen ovale: the evident paradox between the apparently simple treatment and the really complex pathophysiology

The simplicity and high safety profile of the new generation family of devices, and in particular of the last generation of occluder device, has given impetus to the diffusion of patent foramen ovale (PFO) transcatheter closure, which appears to be very simple and safe. Paradoxically, the pathophysiology of PFO is all but simple and the fact that many details of PFO-mediated syndromes are not yet fully understood is taken as proof of improper PFO closure by skeptics. However, on careful in-depth analysis of this apparently straightforward operation, many potential problems can be found at different stages; from a technical point of view, nickel toxicity, the possibility of thrombus formation, presence of residual shunt, malpositioning, and erosions are still active and real problems, whereas the pathophysiology of right-to-left shunt, role of coagulation abnormalities, significance of atrial septal aneurysm and other sources of shunt remain unresolved issues. Multidisciplinary task forces with PFO-related syndromes surveillance programs and highly-skilled interventional cardiologists are likely to increase the effectiveness and safety of PFO management.

Patent foramen ovale: The never-ending story

Several uncontrolled studies suggested a relationship between patent foramen ovale (PFO) and stroke. But recent data indicate that previous studies may overestimate the association between PFO and stroke. First, among patients who have had a cryptogenic stroke under treatment (with either warfarin or aspirin), the main data from the French PFO/atrial septal aneurysm (ASA) and PICSS (Patent Foramen Ovale in Cryptogenic Stroke Study), analyzed separately and in combination, indicate that PFO alone does not announce a significantly increased risk of recurrent stroke or death. But a small increase or decrease in risk cannot be excluded by this meta-analysis. Second, the data concerning the association between PFO and ASA are not clear and variable: the French PFO/ASA study found a significantly increased risk of recurrent stroke in patients with cryptogenic stroke and an association between PFO and ASA when treated medically. In contrast, PICSS found no association between the combined PFO-ASA with stroke or death, but the two populations had meaningful differences. Patients in the PICSS were much older than those in the French PFO/ASA study and had more risk factors for stroke, such as hypertension, diabetes, and history of prior stroke. Third, there were inadequate data to conclude about ASA alone. Possible practice recommendations could come from this meta-analysis: the evidence indicates that the risk of recurrent stroke or death is not different for patients with a PFO who underwent cryptogenic stroke compared to patients without a PFO who underwent a cryptogenic stroke under treatment with either aspirin or warfarin. But aspirin is more preferable (300 mg/d). However, it seems that the association between PFO and ASA confers an increased risk of recurrent stroke in medically treated patients who are less than 55 years of age. This subgroup of younger stroke patients may benefit from other treatments, such as the percutaneous closure of PFO or mini-invasive surgery to a lesser extent, but their efficacy and safety are not yet assessed by large randomized trials. However, we must also keep in mind that some stroke patients with PFO are psychologically attached to their PFO and prefer to close it.

Migraine: traditional or "innovative" treatment? A preliminary case-control study

The aim of this preliminary case-control study was to compare, in patients with migraine and PFO, transcatheter closure of PFO vs. medical treatments. Twelve patients were treated with antimigraine drugs and twelve underwent percutaneous transcatheter closure. All patients were followed-up for 12 months. Our preliminary results seem to confirm that, compared to medical treatment, PFO closure is by far more effective in reducing both frequency, duration and intensity of migraine attacks. Furthermore, the occurrence of prodromal aura is almost abolished.