Outcomes of Transcatheter ASD Closure Guided by 3D-TEE

Atrial Septal Defect (ASD) is a common cardiac diagnosis among adults.Three-dimensional transesophageal echocardiography (3D-TEE) improve the visualization of ASD, its rims and surrounding structures and can be used for guidance during percutaneous transcatheter closure. Proper device size selection is important for success of ASD device closure. 3D-TEE can assess the ASD morphology, maximal diameter, area and determine the device size without balloon sizing during percutaneous closure.There are some adverse outcomes reported in previous studies following transcatheter secundum ASD closure as: residual shunt, new onset atrial fibrillation(AF) and mitral regurgitation(MR)deterioration . These adverse outcomes are responsible for morbidity and mortality following transcatheter ASD closure, so it is essential to study risk factors associated with these adverse outcomes in order to minimize their incidence.The investigators will study the role of 3D-TEE in proper device size selection, also the percentage and predictors of adverse outcomes after device closure guided by 3D-TEE.

The investigators will include 80 patients in a prospective cohort study .

For all patients the following study tools will be done:

1. Written consent.
2. Detailed history including Age, sex, symptoms (NYHA class).
3. Clinical examination.
4. Electrocardiogram (ECG) (to detect baseline rhythm).
5. Two-dimensional transthoracic echocardiography (2D TTE):

   All patients will undergo 2D TTE before device closure to assess:
   * ASD (type, size, shunt direction).
   * Pulsed Doppler quantification of the pulmonary (Qp) to systemic (Qs) blood flow ratio
   * Right ventricle (RV) enlargement: RV linear dimensions are best measured from a RV-focused apical four-chamber view.
   * RV systolic function by :

     1. Tricuspid annular plane systolic excursion(TAPSE) ,
     2. 2D RV fractional area change (FAC)= 100 X \[(end-diastolic area - end-systolic area)/end-diastolic area)\].
   * Pulmonary artery systolic pressure (PASP).
   * Grade of MR by Color Doppler: The color Doppler jet area of MR and left atrial area at the time of midsystole will be measured by the area trace method in the apical 4-chamber view, and the ratio of MR jet area to left atrial area will be calculated. The grade of MR will be determined by the ratio, where 0% to 10%\>\> none/trivial, 10% to 20% \>\> mild, 20% to 40% \>\>moderate, and \>40% \>\> severe.
   * Left ventricle (LV) systolic function by m-mode,
   * LV diastolic function :

     1. Pulsed wave (PW) Doppler of trans-mitral flow during diastole.
     2. Tissue Doppler imaging (TDI).
6. Three-dimensional transesophageal echocardiography (3D-TEE):

   All patients will undergo 3D-TEE before device closure of secundum ASD to assess:
   1. The number of defects.
   2. Defect size: The maximum dimension (length), minor dimension (width), and area by planimetry will be measured from the 3D en face view.
   3. ASD morphology will be categorized by the shape seen in the en face view. ASD will be defined as circular when the minor dimension is \>75% of the maximum length. If the minor dimension is \<75% of the maximum length ASD will be defined as having an oval shape. Asymmetric, irregularly shaped defects that are not elliptical will be defined as having a complex shape.
   4. The surrounding rims: aortic rim, atrioventricular (AV) rim, superior vena cava (SVC) rim, inferior vena cava (IVC) rim and posterior rim.

   According to recent study, the optimal ASD device size will be calculated as :

   Device size = 0.964 x 3Dmax - 2.622 x circular index +7.084 Where maximal ASD diameter on 3D-TEE (3Dmax) and the circular index is defined as the ratio of the maximal to minimal diameters on the 3D-TEE image.
7. Transcatheter secundum ASD device closure procedure:

   All patients suitable for device closure will undergo transcatheter device closure procedure in cath lab under general anesthesia. After venous access is gained following local anesthesia via the right femoral vein, the ASD is crossed using a Multipurpose catheter. The Multipurpose catheter is then exchanged for a device-specific delivery system. Its tip is placed into the left atrium. The left-sided disk is then deployed and gently pulled back against the atrial septum under fluoroscopic guidance in a left anterior oblique projection. To deploy the right atrial disc, tension is maintained on the delivery cable while the delivery sheath is further withdrawn.

   The whole procedure will be under fluoroscopic and 3D-TEE guidance. Device size that will be used in ASD closure according to the previously mentioned formula based on 3D-TEE measurements.
8. Follow up:

   * Clinical follow up for 24 hours to detect post-ASD closure acute heart failure.
   * 2D-TTE will be performed 24 hours post-procedure to visualize the device position and to look for residual shunting and MR grade using color Doppler.
   * Clinical follow up, ECG and 2D-TTE at 6-month follow up to detect new onset AF, residual shunt and MR deterioration.
9. After 6 months of device closure :

Patients will be divided into two groups according to occurrence of adverse outcomes (residual shunt , MR deterioration and new onset AF ) and the following predictors will be evaluated in each group and their influence on occurrence of these adverse outcomes:

Echocardiographic data:

* RV systolic function by TAPSE and FAC on 2D-TTE.
* LV systolic function by m-mode on 2D-TTE.
* LV diastolic function on 2D-TTE.
* Estimated PASP on 2D-TTE.
* ASD shape on 3D-TEE.
* ASD maximal diameter on 3D-TEE.
* ASD minimal diameter on 3D-TEE.
* ASD area on 3D-TEE.
* Size of implanted device.

Eligibility Criteria:
Inclusion Criteria:

* Patients with suitable indication for ASD closure according to recent guidelines :

  1. Impaired functional capacity.
  2. Right atrial and/or RV enlargement.
  3. Left-to-right shunt with \[Qp: Qs\] ≥1.5:1.
  4. Paradoxical embolism.
* Patients with isolated secundum ASD with sufficient rims suitable for device closure.

Exclusion Criteria:

* Small ASD with Qp/Qs \<1.5:1 or no signs of RV volume overload
* A single defect too large for closure (\>38 mm)
* Multiple ASDs unsuitable for percutaneous closure.
* Anterior, posterior, superior, or inferior rim \<5 mm.
* Abnormal pulmonary venous drainage.
* Associated structural heart disease requiring cardiac surgery.
* ASD with severe pulmonary arterial hypertension and bidirectional or right-to-left shunting.
* Intracardiac thrombi diagnosed by echocardiography.