El dorsal ancho y el serrato no necesitan ser seccionados. Aorta y ambas cavas pueden ser canuladas directamente fig. El resto de los pacientes fue extubado en las 6 h siguientes a su llegada a la UCI. Nuestro trabajo presenta varios sesgos. Queremos expresar nuestro agradecimiento al Dr.
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Multiplanar transesophageal echocardiography for the evaluation and percutaneous management of ostium secundum atrial septal defects in the adult.
Corresponding author: Annie Dore. Telephone: E-mail: annie. Received on February 1, ; Accepted on October 3, The purpose of this paper is to review the usefulness of multiplanar transesophageal echocardiography before, during and after percutaneous transcatheter closure of secundum atrial septal defects. Transesophageal echocardiography imaging techniques, including their role in patient selection, procedural guidance and immediate assessment of technical success and complications are described and discussed in this review.
Percutaneous transcatheter closure is indicated for ostium secundum atrial septal defects of less than 40 mm in maximal diameter.
The defect must have a favorable anatomy, with adequate rims of at least 5 mm to anchor the prosthesis. Transesophageal echocardiography plays a critical role before the procedure in identifying potential candidates for percutaneous closure and to exclude those with unfavorable anatomy or associated lesions, which could not be addressed percutaneously.
Transesophageal echocardiography is also important during the procedure to guide the deployment of the device. After device deployment, the echocardiographer must assess the device integrity, position and stability , residual shunt, atrio-ventricular valve regurgitation, obstruction to systemic or venous return and pericardial effusion, in order to determine procedural success and diagnose immediate complications.
Key words: Transesophageal echocardiography; Percutaneous closure; Atrial septal defect; Canada. The role of echocardiography during interventional procedures is well documented 3,4 and several techniques have been described for the guidance of PTC of ASD. Current indications for ASD closure are out of the scope of this paper and can be reviewed elsewhere.
TEE assessment of ASD includes evaluation of the number and localization of the defect s , dimensions and adequacy of the rims, direction and severity of the shunt, and the presence of possible associated defects. The ideal scenario for PTC is a single ASD with a maximal diameter of less than 20 mm, 8 with firm and adequately sized rims. Defects up to 40 mm in diameter with firm and adequate rims have been closed successfully via PTC, as have multiple ASDs and those associated with atrial septal aneurysms.
The size of the ASD changes during the cardiac cycle; the maximal ASD diameter must be measured at the end of ventricular systole. It is critical to recognize the nomenclature and understand the anatomical disposition of the rims or edges bordering the ASD Figure 2. The minimal two-dimensional measurement is taken. Several authors have referred to these edges with anatomical connotations and others with spatial connotations.
For example, some authors describe the "antero-septal rim", which corresponds anatomically to the aortic rim Ao. To simplify this classification we refer to Table 1. For reasons of clarity, anatomic connotations are used herein.
From the mid-esophageal 4-chamber view, the probe should be pulled out with a slight right rotation to permit the localization of the right upper pulmonary vein RUPV rim at the upper-esophageal level Figure 5. Sometimes the Ao is very small, or even absent Figure 7 , this finding makes the procedure more challenging but does not, preclude PTC of the defect.
With slight probe rotation to the right clockwise rotation of the shaft of the probe , the IVC and the superior vena cava SVC are seen. The mid-esophageal bi-caval view provides an excellent view of the inter-atrial septum, allowing interrogation of the septum with CD. The evaluation of the IVC rim is fundamental Figure 8B , because PTC would be very challenging in its absence, 14 it is, however, usually the most diffcult to visualize and measure, and retrofexion of the probe may help when it is not visible in the standard bi-caval view.
It is necessary to perform a slight retroflexion of the probe to obtain a view of both the lower end of the ASD and the CS. The presence of multiple defects of the inter-atrial septum have been reported in 7. In such cases, the device should be implanted in the largest defect, with the smaller adjacent septal defect being enclosed in the area covered by the two disks, hence being occluded by the same device.
A major concern in the presence of two separate septal defects Figure 10 is the possibility of missing other supplementary defects. In these cases, it has been suggested to infate two balloons simultaneously under TEE guidance and to exclude a possible third atrial septal defect with CD assessment.
In summary, the baseline TEE must meet the criteria described in Table 2 in order for the patient to be eligible for percutaneous closure.
In most centers, PTC is performed under general anesthesia with echocardiographic TEE guidance because intracardiac echo without anesthesia remains an expensive option. CD is used to image fow through the ASD and the balloon is then gently pulled back, at which stage color fow on the TEE will disappear when balloon occlusion is complete.
While maintaining firm but not undue pressure on the septum and under continuous TEE guidance, the balloon is slowly defated until it pops through the defect into the right atrium. The amount of contrast needed to infate the balloon to this diameter is carefully recorded and the balloon is then completely defated and withdrawn from the patient.
Afterwards, it is re-infated to the SBD volume and measured against a sizing plate. It is important to have a good alignment when doing the measurement of the SBD, because misalignment will produce incorrect measurements. The ideal image is that of a figure "8" see below. In most centers, the static balloon measurement technique is used. This typically creates an indentation sometimes minimal on the balloon Figure Overstretching of the ASD should be avoided to prevent erosion related to the utilization of oversized devices.
The main advantage of this technique is its short inflation-deflation cycle, making the procedure much simpler. It is important to recognize that only when the largest diameter is strictly craneo-caudal in direction, will it truly estimate the full size of the defect, achieving a figure "8" pattern view. The diameter of the indentation can also be measured with fuoroscopy Figure 12 using calibration markers on the balloon catheter.
SBDs by both methods are compared and measurements are repeated if there is a greater than 1 mm discrepancy. It is recommended to choose a device that is the same size of the SBP to prevent oversizing and erosions. However, some operators prefer devices mm greater than the measured SBD 22 and up to mm greater than the SBD in the presence of large defects, in defects with a deficient or absent Ao, in defects with an aneurismal septum or in the presence of multiple defects.
In older patients, left diastolic ventricular dysfunction associated with elevated flling pressures is observed and may lead to secondary pulmonary hypertension. In these cases, the atrial septal defect, functioning as an over-fow, may mask the presence of left ventricular diastolic dysfunction by an enhanced left-to-right shunt.
If such a mechanism is suspected, temporary balloon occlusion of the defect should permit its unmasking. TEE during device positioning, deployment, and release. Device preparation for delivery is an important process of PTC and requires a meticulous approach on behalf of the interventional cardiologist Figure In order to ensure stability during device delivery, the interventional cardiologist will position a supportive guidewire, through the ASD and left atrium, most often into the left upper pulmonary vein LUPV.
Given the fragility of the left atrial appendage, it is essential to avoid entering this thin-walled structure with catheters or the stiff guidewire, because this could cause perforation and lead to pericardial effusion. After having loaded the device in the delivery sheath, its insertion must be performed under TEE guidance. It is important to ensure that the tip of the delivery sheath is located in the left atrium, before deploying the left atrial disk of the closure device, in order to avoid deployment in the LUPV, the left ventricle or the left atrial appendage as this could cause deformation of the device, device entrapment or perforation of the atrial wall.
Once the correct distal sheath position and the partially opened left disc position are confirmed by TEE, the left disk can be completely deployed Figure The device is then pulled back under TEE guidance toward the IAS so that the lower portion of the device catches the Ao or, in its absence, it encroaches the base of the aortic root. Thereafter the device is pulled toward the RA, so that its superior portion catches the superior aspect of the ASD Figure When resistance of the septum is encountered and TEE confirms good apposition of the LA disk with the rims of the ASD, the right atrial disk of the prosthesis is opened inside the RA, allowing the prosthesis to grasp the rims of the ASD between its two disks Figure Under TEE guidance, the occluder device is scanned in 2-D and with CD in several views, looking for proper positioning and residual shunts.
The echocardiographer must confirm that both disks are fattened with good apposition, and assess residual shunting. It is not uncommon to have discrete residual central or peri-prosthetic shunts, which usually will disappear after endothelialization of the occluder device Figure When the Ao is absent, a typical "Y" pattern of the device being sandwiched around the AA should be seen Figure Failure to achieve this "Y" pattern of both disks requires device repositioning before release because this could lead to laceration of the aortic wall.
When a large Eustachian valve EV or Chiari network is present, it should be mentioned to the operator because it can cause device entrapment during deployment of the right atrial disk. This serious complication can be prevented by pushing back the structure using a second catheter.
Nearby structures might be compromised after positioning of the occluder device. Mitral valve leafets might be encroached by the occluder device, producing mitral regurgitation in a defect with a defcient AV rim and, infow from the SVC and RUPV might be compromised in a defect with a defcient SVC rim. The Minnesota maneuver or wiggle is performed prior to release, to ensure stability of the occluder device. After this maneuver, the device is released.
It is not uncommon to observe a change of position of the device en bloc with the inter-atrial septum, as tension is relaxed Figure A thorough evaluation for presence of residual shunts is performed for future correlation. The device and adjacent structures are evaluated 8 to rule out device 14 mal-positioning, interference with aortic, mitral, or tricuspid valvular function, caval, CS, or pulmonary venous return obstruction, and pericardial effusion. The presence of residual shunts should be reassessed; this could be achieved with contrast echocardiography with agitated normal saline, which opacifies the right sided cardiac chambers and may demonstrate the un-opacified jet of the left to right shunt.
The potential of paradoxical embolus may be assessed by increasing right sided pressures with the Valsalva maneuver. Transcatheter ASD closure is followed by near normalization of heart structure and function.
The reversal of RV volume overload has been shown as early as 3 weeks post procedure in children and 9 months in adults, 28 also systolic pulmonary artery pressure dropped to near normal levels during the following few months. Abnormal septal motion of the inter-ventricular septum is expected to normalize shortly after the procedure. It is important to be aware of the potential long term complications such as encroachment of mitral or aortic valve leafets, impairment of fow from the pulmonary veins, reactive or hemorrhagic pericarditis, and migration or dislodgement of the device.
The use of aspirin 48 hours prior the procedure and for at least six months after the procedure is recommended, as well as antibiotic prophylaxis 7 for six months after the procedure.
Follow up should include transthoracic echocardiography TTE the day following device deployment. Long-term follow up should be performed with TTE at three, six and 12 months after the procedure and when clinically indicated thereafter.
Percutaneous closure of significant shunting associated with secundum ASD represents an attractive less-invasive alternative therapy to surgery and is being increasingly performed worldwide. TEE is the ideal imaging and assessment tool to evaluate and guide procedures and determine immediate procedural success, while ruling out complications.
Familiarization with TEE in this context is essential for the echocardiographer involved in the modern care of patients with ASD. Hoffman JI, Christianson R. Congenital heart disease in a cohort of 19, births with long-term follow-up.
Am J Cardiol ; Congenital heart disease among liveborn children in Liverpool to Implications for surgical treatment. Br Heart J ; Echocardiography-guided interventions. J Am Soc Echocardiogr ;