**4. Pre-operative investigations**


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*Minimally Invasive Right Anterior Mini-Thoracotomy Aortic Valve Replacement*

4.CT-scan: Pre-operative non-contrast axial CT scan is mandatory before MIAVR through a right anterior mini-thoracotomy (RAMT) approach, in contrast to mini-sternotomy (MS) approach. Patients are suitable for RAMT-MIAVR only if the following criteria are met: (a) At the level of main pulmonary artery, the ascending aorta is rightward (more than one half located on the right in respect to the right sternal border.) (b) The distance from ascending aorta to sternum does not exceed 10 cm. (c) The alpha angle (angle between angle midline and

*At the level of the main pulmonary artery, the ascending aorta is rightward (more than one half located on the right in respect to the right sternal border). The distance from the ascending aorta to the sternum does not exceed 10 cm.*

5.Coronary angiography: It is the gold standard investigation for detection of coronary artery anatomy and pathology. Its importance is (a) to detect abnormal coronary anatomy which influences myocardial protection strategies (b) in finding of critical coronary artery lesions which may change an isolated AVR procedure to AVR + CABG. This will change the approach for

6.Peripheral femoral Doppler: It is an extremely important investigation to assess the size of femoral vessels especially the femoral artery. Diameter less than 5 mm may not be adequate for femoral arterial cannulation and to maintain adequate flows on cardiopulmonary bypass. Also, it is important to rule out any atherosclerotic plaques in femoral arteries, which can interfere with the passing of a guide wire for femoral cannulation. If so, it may be necessary to change the

The two most commonly used approaches today are (a) Ministernotomy and (b)

a.Ministernotomy: It is the most common technique in use. A 6–10 cm midline vertical incision, with a partial J sternotomy is made. Murtuza et al. [27] reported superior results in peri-operative mortality, shorter ventilation time,

approach. Few studies have analyzed this approach. Glauber et al. [28] in their 192 patient series reported 0.7% in-hospital mortality. Compared to ministernotomy, right anterior mini-thoracotomy patients had lower post-operative

b.Right anterior minithoracotomy: It is the second most frequently used

ICU and hospital stay compared to full sternotomy AVR.

inclination of ascending aorta) should be >45° (**Figure 1**).

the procedure required to a full sternotomy.

cannulation site from femoral to central.

Right anterior minithoracotomy (**Figure 2**).

**5. Surgical techniques**

*DOI: http://dx.doi.org/10.5772/intechopen.85242*

**Figure 1.**

*Minimally Invasive Right Anterior Mini-Thoracotomy Aortic Valve Replacement DOI: http://dx.doi.org/10.5772/intechopen.85242*

**Figure 1.**

*Cardiac Surgery Procedures*

**3.3 Clinical assessment**

Pre-operative physical examination is a mandatory step in the work up and

a.Previous incisions in the chest and groin: These indicate adhesions and distortion of anatomy in the area of dissection. If there are adhesions around right atrium, femoral venous cannulation is a good alternative. It allows for increased exposure

b.Increased chest rigidity: Partial retraction of sternum in upper hemi-sternotomy (UHS) or ribs in anterior right mini-thoracotomy (ART) is required for exposure. Increased chest rigidity due to previous chest surgery, chest trauma or ankylosing spondylitis can compromise the retraction required for exposure. Very muscular and, more commonly in young patients, slightly stiff chest walls can be encountered. Costochondral cartilages can be transected in patients with narrow intercostal spaces. Such a step helps to increase exposure. These can be sutured

c.Chest wall deformity: Pectus excavatum is the most common chest wall deformity [25]. It displaces heart to the left. Patients with moderate or severe pectus excava-

d.Morbid obesity: In obese patients the heart is more cranially displaced, due to excess fat in abdomen. It improves the exposure and access to ascending aorta. But there is also increased difficulty in getting into chest cavity due to abundant

e.Height: In very tall patients (>185 cm), peripheral venous cannula may not reach the superior vena cava leading to insufficient venous drainage and distention of right atrium/ventricle. Insertion of another venous cannula into superior vena cava and connecting it to venous line through Y-connector can help improve the venous drainage. However, the heart is more caudally placed in very tall patients, impacting the distance to be negotiated to reach the

1.Chest X-ray: It helps to (a) identify acute and chronic lung pathology, (b) assess basic thoracic anatomy and (c) To note generally that aortic valve is in

2.ECG: Pre-operative conduction disorders are an independent risk factor for permanent pacemaker insertion [26]. Use of rapid deployment or suture less bio prosthesis increases the risk of complete atrioventricular block. The possible reason could be increased pressure on aortic annulus and left ventricular

3.Echocardiography: It is the gold standard to assess the aortic valve pathology. Size of the aortic annulus, gradients across the aortic valve, bicuspid or tricuspid aortic valve, and left ventricle ejection fraction are all the important

outflow tract (LVOT) and then on the conduction tissue.

information to be gathered prior to surgery.

appropriate selection of patients. Important considerations are:

of aortic root and ascending aorta.

back into position at the end of procedure.

tum with Haller index >3.2 are contraindicated.

subcutaneous and mediastinal fat.

aortic valve.

**4. Pre-operative investigations**

close relation to 4th intercostal space.

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*At the level of the main pulmonary artery, the ascending aorta is rightward (more than one half located on the right in respect to the right sternal border). The distance from the ascending aorta to the sternum does not exceed 10 cm.*

