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Fig. 19.6 Aortic anastomosis. The suture line commences at the 4:30 position in a clockwise fashion to the 12 o’clock position. The second arm of the suture is then used to complete the anastomosis from the 4:30 position running in an anticlockwise fashion

suture is used for the aortic anastomosis starting from outside-in at the 4:30 position of the recipient aorta and progressing rightward along the posterior wall of the aorta and up the right side of the anastomosis to the 12:00 position (Fig.19.6). During this time, the recipient is rewarmed. The second arm of the aortic running suture is then progressed up the left side of the anastomosis towards the 12 o’clock position to complete the anastomosis and tied against the rst arm. Retrograde blood cardioplegia is discontinued, and the coronary sinus cannula is removed. A cardiotomy sucker is connected to the DLP vent in the ascending aorta to de-air the aortic root before the aortic cross-clamp is removed and the donor heart reperfused. Mean arterial pressure of 60 mmHg is maintained during this phase. The remaining segments of the LA and PA anastomoses are then completed during donor heart reperfusion. Debrillation of the donor heart is attempted when body temperatures reach 34°C (Fig.19.6).

IVC Anastomosis

The caval anastomoses are best performed from the left side of the operating table. Since the donor heart is being perfused, tilting the operating table to the reverse Trendelenburg position and towards the left will divert coronary sinus blood away from the IVC towards the right ventricle. A cardiotomy

A. Al-Adhami and S. Tsui

Aortic root vent

Cardiotomy sucker

Fig. 19.7 Inferior vena cava anastomosis. The posterior wall of the anastomosis is constructed rst starting at the right lateral margin 9 o’clock (corresponding to the double pericardial fold between the IVC and the right inferior pulmonary vein) progressing leftward along the posterior wall towards the coronary sinus and then upward to the anterior wall of the anastomosis. The second arm of the suture is then used to complete the complete the anastomosis from the 9 0’clock position running in a clockwise fashion

sucker can be placed in the coronary sinus via the SVC stump and another is placed in the most dependent point of the pericardial cavity behind the IVC (Fig. 19.7). A stay suture is placed at the 12 o’clock position on the donor IVC and retracted cranially. A second stay suture is placed in the corresponding 12 o’clock position in the recipient IVC and retracted anteriorly. An extra-long 3-0 polypropylene suture is used for the IVC anastomosis starting at the right lateral margin of the donor and recipient IVC cuffs which can be identied by the remnants of the divided pericardial reections between the right inferior pulmonary vein and the IVC (9 o’clock position).An additional stay suture can be placed in the donor and recipient IVC cuffs at the 6 o’clock position and retracted towards the patient’s left hip to elevate and align the IVC cuffs to facilitate anastomosis. The posterior wall of the IVC anastomosis is constructed rst starting at the right lateral margin progressing leftward along the posterior wall towards the coronary sinus and then onto the anterior wall (from 9 o’clock to 6 o’clock, 3 o’clock and then 12 o’clock). The other arm of the suture is then progressed along the anterior wall to complete the anastomosis (from 9 o’clock to 3 o’clock). There is always a degree of compensatory suturing required by travelling longer distances between bites on the recipient IVC relative to the donor IVC to account for the differences in their respective circumferences. If there is too much size mismatch, the anterior margin of the donor IVC cuff can be incised to increase its circumference to match that of the recipient (Fig.19.7).

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SVC Anastomosis

Given a very thin wall, the SVC anastomosis more at risk of stenosis and compression than the IVC. To avoid this potential pitfall, the SVC cuffs must be cut to the appropriate length and correctly aligned. Gentle traction is applied to the donor SVC and this is transected at the point where it reaches the recipient SVC and thus eliminating excess tissue. To correctly align the stumps of the donor and recipient SVC, a stay suture is placed at the 12 o’clock position and retracted leftwards. The 12 o’clock position on the recipient SVC corresponds to the SVC cannulation point and on the donor SVC, the apex of the RA appendage ridge. The SVC anastomosis is performed using a 4-0 polypropylene suture commencing posteriorly at the 6 o’clock position, diagonally opposite the 12 o’clock stay suture (Fig. 19.8). The left half of the SVC anastomosis is performed rst from the endothelial aspect and once the 12:00 stay suture is reached, the second arm of the suture is used to perform the right half of the anastomosis from the adventitial aspect. Bites should be shallow and closely spaced to avoid gathering excessive tissue and narrowing the anastomosis. Both caval tapes can now be released (Fig.19.8).

De-airing andWeaning fromCPB

In preparation for weaning the recipient from CPB, an adrenaline infusion is commenced at a rate of 0.05–0.07 mcg/kg/min. Other inotropes and vasoconstrictors can be added to achieve a mean arterial pressure of 75 mmHg. The plasma haemoglobin level is restored to 100g/L with blood transfusions and/or haemoltration if necessary. Acidosis should be corrected aiming for a base excess of ±2 mEq, and electrolyte levels should be normalised. Temporary right ventricular and right atrial pacing wires are secured. Aortic root and RSPV vent suction should be maintained until de-airing is complete. The heart is then progressively lled to achieve a central venous pressure of 6–8 mmHg. Transoesophageal echocardiography is assessed continuously to for ventricular lling, contractility, and completeness of de-airing. When the LA is sufciently lled, the RSPV vent can be removed and the cannulation site repaired. As cardiac ejection increases, CPB is gradually weaned off. Aortic root suction is maintained at 500 mL/min until complete de-airing is conrmed on echocardiography. After separation from CPB, the caval canulae and the aortic root vents are removed. Protamine sulphate is administered, and the aortic cannula is removed. A pulmonary artery catheter is routinely oated, and measurements are taken. Inotropes and vasocontractions are adjusted accordingly. The right pleural cavity is widely opened to reduce the risk of late cardiac tamponade. General haemostasis is conrmed, pericardial and pleural drains are inserted, and the sternum is closed. In instances where there is a restrictive pericardial cavity, extensive pericardial release or pericardiectomy may be required to prevent cardiac compression and hemodynamic comprise on chest closure. In cases of signicant primary graft dysfunction, the sternum may be intentionally left open for a period of a few days prior to denitive closure or temporary mechanical circulatory support may be required.

Fig. 19.8 Superior vena caval anastomosis. A retraction stay suture is placed at the 12 o’clock position in the donor (in line with the RA ridge) and recipient (in line with the venous cannulation site) SVC and retracted leftward. The anastomosis is constructed rst starting at 6 o’clock progressing leftward (anticlockwise) towards 12 o’clock. The second arm of the suture is then used to anastomosis the right half of the SVC

Special Circumstances

Bi-atrial Implantation Technique

The bi-atrial (Shumway) technique for heart transplantation was rst described in the 1960s and was the original technique in the early era of heart transplantation. Due to associated complications relating to sinoatrial nodal injury and sequalae of atrial enlargement including arrythmias, conduction abnormalities, embolic events, and atrioventricular valve incompetence, it is now rarely performed. On occa-

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sions, the bi-atrial technique can sometimes be useful, e.g. in specic cases of congenital heart disease and in certain reoperative scenarios where mobilisation of the native SVC and IVC proves difcult due to dense adhesions. The donor operation is as for the bi-caval technique. In contrast to the bi-atrial technique however, the donor RA is opened with a curvilinear incision extending from the right lateral edge of the IVC towards the RA appendage (Fig.19.9). During cardiectomy, the technique for ventriculectomy is as described for the bi-caval technique with the exception that the atrial septal incision is made closer to the tricuspid valve annulus. This will leave behind a double layer of atrial septum to permit separate left and right atrial anastomoses. The entire recipient RA and LA are preserved with the exception of the LA appendage (Fig.19.10).

The LA, PA, and aortic anastomoses are performed as described in the bi-caval technique. The aortic cross-clamp is then removed, the donor SVC stump is shortened and ligated. The RA anastomosis is performed during donor heart reperfusion. The cut edge of the donor RA incision extends onto the donor IVC cuff. Using an extra-long 3-0 polypropylene suture, the RA anastomosis is constructed starting at the cranial end between the posterior margin of the donor RA incision and the recipient atrial septum (Fig. 19.11). As the suture line reaches the donor IVC cuff, extra care should be taken to avoid distortion or obstruction of the donor coronary sinus. The second arm of the suture is then used to construct the anterior rim of the anastomosis from cranial to caudal to meet with the rst arm of the suture and then tied (Figs.19.9,

19.10, and 19.11).

A. Al-Adhami and S. Tsui

Fig. 19.10 Recipient preparation and cuff preparation for bi-atrial heart transplantation

Tied superior

vena cava

Repaired left atrial appendage

Curvilinear

incision

IVC

Fig. 19.9 Donor heart preparation for bi-atrial heart transplantation. The donor right atrium is opened with a curvilinear incision extending from the right lateral edge of the IVC towards the right atrial appendage

Fig. 19.11 Right atrial anastomosis for bi-atrial heart transplantation. The right atrial anastomosis is constructed starting at the cranial end of the donor and recipient RA cuffs and progressed caudally along the posterior rim of the anastomosis. After reaching the caudal extent of the anastomosis, the needle is switched and the anterior rim of the anastomosis is completed in the cranial to caudal direction

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Implantable Left Ventricular Assist Devices (LVADs)

The use of implantable LVAD as a bridge to heart transplant has increased over the last decade and has undoubtedly improved the long-term outcomes of patients with advanced heart failure. However, this has introduced new technical challenges for the heart transplant surgeon. The transplant procedure in these circumstances must be viewed as a sequel of the LVAD implant, where technical considerations should be taken into account that would facilitate the subsequent transplant procedure. The LVAD outow graft should be anastomosed laterally on the aorta and as proximal as possible to allow enough length of recipient ascending aorta for the subsequent transplant procedure. The lie of the device outow graft should be made as lateral as possible curving around the RA, thereby avoiding the area immediately behind the sternum. Moreover to reduce the likelihood of adhesions between the sternum and the outow graft, ascending aorta, and the right ventricle, the LVAD implanting surgeon should either close the pericardium directly or use a protective synthetic membrane (e.g. GORE-TEX or silicone).

Donor organ retrieval teams should be informed to ensure that long lengths of major vessels are included with the donor heart to account for any potential difculties. After resternotomy, pericardial dissection, and initiation of CPB, the LVAD speed should be reduced to avoid the risk of air entrainment and embolisation. Moreover, the LVAD should not be switched off until the outow graft is clamped to prevent regurgitant ow through the LVAD with resultant LV distension and pulmonary congestion.

Following sternotomy, it is important to delineate the native pericardial edges which are most easily found at the

margins of the synthetic membrane if one was used at the time of LVAD implantation. In contrast to standard reoperative cardiac procedures where the diaphragmatic pericardium is usually the best site for starting cardiac dissection, this area is often densely scarred from the presence of the LVAD and outow graft.

Clinical Outcomes

The International Society for Heart and Lung Transplantation (ISHLT) Thoracic Organ sTransplant Registry has recorded data on more than 150,000 heart transplants worldwide since 1982. The median survival of the whole cohort is 12.5years. The most common causes of early mortality include primary graft dysfunction, rejection, and infection. Cardiac allograft vasculopathy, nonspecic graft failure, malignancy, and renal dysfunction are common causes of late mortality. Of the more recent series, reported 1-, 5-, 10-year survival have increased to 86%, 74.9%, 58.1%, respectively. The quality of life and functional recovery after transplantation are excellent with the majority of recipients not requiring further hospitalisations and the majority scoring ≥80% on the Karnofsky Performance Status Score denoting people able to carry on normal activity and work without need for specic care.

Suggested Reading

Berman M, Tsui S.Orthotopic heart transplantation. In: Oniscu GC,

Forsythe JLR, Pomfret EA, editors. Transplantation surgery. Springer surgery atlas series. Berlin, Heidelberg: Springer; 2019.

https://doi.org/10.1007/978- 3- 540- 73796- 4_2.

Heart-Lung Transplantation

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MuhammadU.Raq andStevenTsui

Heart-lung transplantation is a complex, infrequently performed operation. The indication for this operation is restricted to those with combined advanced heart and lung failure.

Key facts to consider include:

• Careful mediastinal dissection is paramount to preserve

the phrenic, left recurrent laryngeal and vagal nerves.

• Meticulous haemostasis must be achieved after excision

of the native heart and lungs before donor organ

implantation.

Indications

• Idiopathic pulmonary hypertension with non-recoverable

cardiac impairment.

• Congenital heart disease with Eisenmenger syndrome.

• Selected cystic brosis patients.

Preparation ofRecipient

Preoperative correction of clotting abnormality is advisable according to local protocol. The patient is prepped and draped in the supine position with arms tucked-in on the sides.

A median sternotomy and a midline pericardiotomy are performed (Fig.20.1). Both pleurae are opened and accessible pleural adhesions are released before heparin is administered to minimise bleeding. The pleural adhesions are either cauterised, ligated with surgical ties and divided or a staple gun can be used. After systemic heparinisation and achieving

M. U. Raq · S. Tsui (*) Department of Cardiothoracic Surgery and Transplantation, Royal Papworth Hospital, Cambridge, UK e-mail: Muhammad.raq@nhs.net; steven.tsui@nhs.net

Fig. 20.1 Median sternotomy with intact pericardium

the appropriate activated clotting time (ACT), cardiopulmonary bypass is established by inserting an aortic cannula in the proximal aorta arch and bi-caval venous cannulation (the SVC can be cannulated directly with a right- angled cannula). The patient is systemically cooled to 30°C.

The inferior and superior vena cavae are snared with nylon tapes, and a cross clamp is applied across the distal ascending aorta. Cardiotomy is performed by incising the right atrium on the atrial side of the atrioventricular groove and extending the incision into the coronary sinus. The left atrium is entered by a stab incision in the fossa ovalis and extending this cranially towards the left atrial roof. From this

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point, the incision is directly towards to base of the left atrial appendage and then the posterior mitral valve annulus. From the fossa ovalis, the stab incision is then extended caudally towards the coronary sinus and then along the posterior mitral annulus until it meets with the cranial incision. The SVC is divided just cranial to its junction with the right atrium. The rest of the right atrium is incised leaving a 3cm cuff of tissue around the recipient IVC for anastomosis with the donor IVC.The aorta and pulmonary artery are then transected at the sino-tubular junction, and the heart can be removed (Fig.20.2).

If a domino heart transplant is planned (where the native heart of the heart-lung recipient is to be used as a donor heart for a heart transplant recipient), an aortic root cardioplegia cannula is inserted, aortic cross clamp is applied, and antegrade cardioplegia is administered before cardiectomy. Careful dissection is performed to excise the domino heart by keeping the right atrium intact, leaving only a two centimetre cuff of tissue around the IVC of the heart-lung recipient and dividing the four pulmonary veins individually.

Once the heart is removed, the posterior left atrial wall is divided vertically in the midline (Fig.20.3).

The pulmonary ligaments are either divided using diathermy or divided between ligatures to ensure haemostasis. The phrenic nerves are identied and carefully preserved.

M. U. Raq and S. Tsui

Fig. 20.2 Recipient heart excised leaving a left atrial cuff and stumps of recipient SVC, IVC, aortic and pulmonary artery

Fig. 20.3 Midline division of recipient posterior left atrium

A longitudinal slit in the pericardium is created posterior to the phrenic nerves just anterior to the right and left pulmonary veins for hilar mobilisation. Each half of the hemisected left atrial cuff is retracted anteriorly to allow division of the pericardial reections from the back of the superior and inferior pulmonary veins (Fig.20.4). This incision in the pericardium is then extended cranially to encircle the respective pulmonary artery and caudally beyond the inferior pulmonary vein to provide a sufciently large window through which the donor lung could pass.

The hilar structures are released from the pericardial and pleural reections by diathermy. Denser tissue bridges and lymph nodes are best divided between ligatures to ensure haemostasis. Posterior to the bronchi, soft tissues should be teased away by blunt dissected with a dental swab to avoid injury to the vagus nerves. When dissecting around the bronchi, special attention is required to Liga-clip or ligate any substantial bronchial arteries. Each main bronchus is stapled with a TA-30 stapler just proximal to the upper lobe bronchus,

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Fig. 20.4 Division of the pericardial reections from the back of the pulmonary veins

and the main bronchus is transected distal to the stapler with a blade. Any soft tissue behind the bronchi can then be divided between ligatures. The lungs are free now and can be removed from the operative eld.

On the right side, the pulmonary artery needs to be dissected away from the back of the SVC; the left atrial roof needs to be separated from the posterior mediastinum where the oblique sinus of the pericardium creates the pericardial reection. The ligamentum arteriosum between the left pulmonary artery and aortic arch is spared by leaving a 1cm disc of pulmonary artery attached to the underside of the aortic arch, avoiding injury to the left recurrent laryngeal nerve (see Fig.20.5). Occasionally, the stump of the ligamentum may need over sewing if patent.

Once the lungs are removed, a Roberts artery forceps is applied to each stapled bronchial stump. Caudal traction on the Roberts brings the distal trachea in to the operative eld. The carina is exposed by incising the bro-fatty sleeve of peri-carinal tissue. The endotracheal tube is withdrawn into the upper trachea and the distal trachea is opened transversely just proximal to the carina with an incision between the cartilaginous rings, leaving the membranous trachea intact. Care needs to be taken not to denude the distal trachea unnecessarily to avoid devascularising the tracheal stump. Two 3-0 polypropylene sutures are applied to the 3 and 9 o’clock positions on the tracheal stump as stay sutures for traction. The tracheal

Fig. 20.5 Exposure of the distal trachea through the opening in the posterior pericardial following removal of the posterior left atrial wall. A 1 cm disc of pulmonary artery can be seen attached to the underside of the aortic arch by the ligamentum arteriosum

transection can then be completed by dividing the remaining membranous trachea without undue tension (Fig.20.4).

Ample time is now spent on meticulous haemostasis of the posterior mediastinum using a combination of Liga-clips, diathermy, and suture ligation (Fig.20.5). This is because once the heart-lung block has been lowered inside the recipient, access to the posterior mediastinum will become very limited.

Donor Heart-Lung Implantation

General inspection of the donor heart-lung block is performed for quality assessment and orientation. The donor trachea is transected just cranial to the carina. The donor heart-lung block is then placed onto the epigastric area of the recipient’s abdomen. The previously placed 3-0 polypropylene traction sutures on the recipient trachea are passed through the corresponding sides of the donor trachea. The tracheal anastomosis is commenced by suturing

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Fig. 20.6 Tracheal anastomosis commences at the 3 o’clock position of the recipient tracheal stump and working clockwise to anastomose the membranous tracheal

the membranous part, starting at the 3 o’clock position of the recipient tracheal stump and running the continuous suture in the clockwise direction. After the rst few sutures, the donor heart-lung block is delivered into the chest cavity (Fig.20.6). The donor left lung is placed into the left pleural cavity through the pericardial slit posterior to the phrenic nerve followed by the donor heart. The right lung is then lowered into the right pleural cavity. Initially placing the heart in the left pleural space greatly enhances the exposure for the tracheal anastomosis.

The tracheal anastomosis is completed by starting at the 3 o’clock position of the recipient tracheal stump and working with one end of the suture clockwise until it reached the 12 o’clock position. The other end of the suture is then brought from the 3 o’clock position anti-clockwise until it meets with the rst suture at the 12 o’clock position and the sutures are tied (Fig. 20.7). The soft tissue overlying the anterior surface of the tracheal anastomosis is approximated with a 4-0 polypropylene suture. At this stage, the anaesthetist can perform a breoptic bronchoscopy to check the tracheal anastomosis and clear the airways of any spillage and secretions.

The heart is now returned into the pericardial cavity. The donor ascending aorta is cut to the correct length and anastomosed with the recipient aorta using a 4-0 polypropylene suture (Fig.20.8). An aortic root cannula (if not inserted initially) is inserted for de-airing of the heart before the aortic

M. U. Raq and S. Tsui

Fig. 20.7 Tracheal anastomosis close-up

Fig. 20.8 Aortic anastomosis

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cross clamp is released. Now the donor heart is reperfused, the optimal mean arterial blood pressure is 60–70 mmHg. The patient is now rewarmed.

The IVC and SVC anastomosis are performed using 3-0 and 4-0 polypropylene sutures, respectively. This is best carried out from the left side of the recipient. To ascertain correct orientation, a stay suture is used on the IVC where the pericardial reection was present (right lateral surface); while for the SVC, the 12 o’clock position using the anterior surface as a reference for orientation. Surgeons must be aware that the recipient IVC cuff is more than twice the circumference of the donor, therefore careful suturing is required for correct size matching (Fig.20.9).

All anastomoses are checked for the haemostasis. Lung ventilation is commenced, and careful inspection of the lungs must be performed to exclude torsion of the lobes in each lung. Atrioventricular pacing wires are inserted. Once the patient is rewarmed, pre-weaning checks are performed aiming for a haemoglobin concentration of 100 g/L, base excess of ±2 mEq and appropriate inotropic and chronotropic agents, as required. The right heart is de-aired through the pulmonary trunk before it is repaired. The patient is weaned off cardiopulmonary bypass and decannulated. Heparin is reversed with protamine, and haemostasis is achieved. A posterior pleural drain is placed in each paravertebral gutter together with an anterior and a posterior pericardial drain. The sternotomy is closed in a standard fashion once satisfactory function and haemostasis are achieved.