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expose the femoral artery and vein before opening the chest. If the right ventricle is injured during sternal
opening, expeditious femoral cannulation and cardiopulmonary bypass can be achieved.
Recipient Coagulopathy
Excellent hemostasis is critical during the dissection of the recipient's native heart. Recipients with right heart
failure usually have liver congestion and coagulopathy, which may lead to excessive blood loss.
In redo surgeries, the native heart is dissected so that the superior vena cava, inferior vena cava, and the
ascending aorta are accessible for cannulation and cross-clamping. The remainder of the dissection can be
completed once the heart is arrested.
Clot Embolization
Patients with end-stage heart disease and global hypokinesis are at high risk of developing left ventricular
thrombus. It is important to minimize the manipulation of the native heart before aortic cross-clamping in order to
reduce the risk of clot dislodgment and possible embolization.
Injury to Bypass Grafts
In patients who have undergone previous coronary artery bypass grafting, it is important to identify the left
internal thoracic artery and other conduits and to protect them during dissection of the heart. Any graft injury or
manipulation leading to spasm or distal embolization of debris may result in hemodynamic instability.
Aortic and bicaval venous cannulation are performed (see Chapter 2). The superior and inferior venae cavae are
cannulated as distant from the heart as possible. This will allow adequate vena caval cuffs for tension-free
anastomoses to the donor heart. Cardiopulmonary bypass is initiated once the donor heart is in the operating
room and the patient is cooled to 28°C. The aortic cross-clamp is applied, and cardioplegia is administered into
the aortic root until the native heart is arrested. The snares around the superior and inferior venae cavae are
tightened and the native heart is excised.
BICAVAL TECHNIQUE
The excision of the recipient's native heart is begun with an incision in the right atrial appendage, 1 cm from and
parallel to the atrioventricular groove. The incision is extended inferiorly toward the inferior vena cava.
Superiorly, the incision is extended onto the roof of the left atrium, between the superior vena cava and aorta.
The aorta is then transected circumferentially approximately 1 cm distal to the sinotubular junction. The
pulmonary artery is divided approximately 2 cm distal to the pulmonic valve. The atrial septum, which is now
exposed, is incised through the fossa ovalis. The incision is extended superiorly to the dome of the left atrium to
meet the superior extension of the right atrial incision. It is then directed toward the base of the left atrial
appendage. Inferiorly, the incision extends across the posterior left atrial wall parallel to the coronary sinus. The
inferior aspect of the right atrial incision is extended onto the medial aspect of the inferior vena cava and
posterior to the coronary sinus to meet the left atrial incision. With the apex of the heart elevated out of the
pericardium, this incision is extended to the base of the left atrial appendage, completing the left atrial excision.
The recipient's native heart is delivered off the field. A portion of the remaining wall of the right atrium is removed,
leaving cuffs of superior and inferior venae cavae. The cuffs of recipient left atrium, inferior vena cava, superior
vena cava, aorta, and main pulmonary artery are prepared for anastomosis to the donor heart (Fig. 11.4).
Optimal hemostasis of exposed muscle in the left atrial wall is accomplished with electrocautery before bringing
the donor heart onto the operative field. A vent is placed through the recipient's right superior pulmonary vein into
the left atrium with the tip in the left inferior pulmonary vein. The vent is inserted through a purse-string suture
and connected to an active suction to remove the pulmonary venous return that can warm the donor heart.
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FIG. 11.4 The recipient's native heart has been removed, leaving a cuff of left atrium. The transected pulmonary
artery, aorta, inferior and superior venae cavae are shown.
Warm Ischemia of Donor Heart
If a vent is not used, the accumulation of venous return from the lungs can lead to warming of the donor heart
which may negatively impact the function of the allograft.
The donor heart is inspected again for a patent foramen ovale and valvular lesions by the implanting surgeon.
Any clots noted on the valves are removed by cold saline irrigation.
Incisions are made connecting the two right and two left pulmonary vein orifices of the donor heart. A third
incision then connects these two openings to create one large left atrial cuff (Fig. 11.5). The aorta and the
pulmonary artery are dissected free from one another. If the donor heart has been harvested with attached
branch pulmonary arteries, these are incised posteriorly to create a confluence, which is then trimmed to the
appropriate length (Fig. 11.5). The implantation of the donor heart is begun with the left atrial anastomosis, which
is started at the level of the left atrial appendage (Fig. 11.6). This suture line is performed with 3-0 Prolene using
an everting-edge technique,
approximating intima to intima, which minimizes the risk of suture line clot formation.
FIG. 11.5 The donor heart is prepared for implantation.
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FIG. 11.6 The implantation of the donor heart begins with the left atrial anastomosis.
The use of a large noncutting circular needle allows adequate bites of both the donor and recipient left atrial
walls to be taken. By incorporating 8 to 10 mm of donor and recipient tissue in this everting manner, hemostasis
is better ensured. This is especially important for the left atrial suture line, which is difficult to expose after the
transplant is completed.
The left atrial suture line is continued inferiorly and then anterior to the recipient's right inferior pulmonary vein.
The suture is tagged when the suture line reaches the level of the right superior pulmonary vein. The second
needle is used to complete the left atrial suture line superiorly. Before securing the suture line, a 12-French chest
tube flushed with cold plasmalyte is placed under direct vision into the left ventricle and the suture is snared
around the chest tube. The flow of plasmalyte is begun and adjusted to 300 to 500 mL per hour for optimal
cooling of left ventricular cavity.
Malalignment of the Venae Cavae
The surgeon must be sensitive to the respective positions of the recipient and donor inferior and superior venae
cavae while constructing the left atrial suture line. If the inferior and superior venae cavae are not lined up
appropriately, these anastomoses may be compromised.
The pulmonary artery of the donor heart is anastomosed to the recipient's pulmonary artery using 4-0 Prolene
suture. In patients with preexisting pulmonary hypertension, this suture line may be reinforced with a strip of
donor pericardium.
Pulmonary Artery Kinking
Kinking of the pulmonary artery may occur when the heart is filled. This may be caused by leaving the donor
pulmonary artery too long. It also may occur if the donor ascending aorta and pulmonary artery are not
adequately dissected free of one another. In either case, a gradient is created across the pulmonary artery
anastomosis, which results in right ventricular hypertension and dysfunction.
While the patient is being rewarmed, the aortic anastomosis is performed using 5-0 Prolene continuous suture
(Fig. 11.7). This suture line is always reinforced with a strip of donor pericardium. After the completion of this
anastomosis, the left ventricle is deaired before reperfusion of the heart begins. The chest tube that was used for
cooling the inside of the left ventricle is removed, and the left atrial suture line is secured.
Modified reperfusion solution is administered into the aortic root at a pressure of 40 mm Hg for 3 to 5 minutes.
After this period, the modified reperfusion is switched to leukocyte-depleted blood until the aortic cross-clamp is
removed (for a minimum total of 10 minutes).
FIG. 11.7 Completed bicaval heart transplant.
There is ample experimental data suggesting that modification of the initial reperfusate improves myocardial
functional recovery after regional or global ischemia. The modification of the initial reperfusate involves
leukofiltration, addition of substrates such as aspartate, glutamate, and glucose for metabolism, addition of
magnesium to minimize calcium influx, supplementation with dextran to reduce cellular swelling, and addition of
nitroglycerin to ensure homogeneous distribution of reperfusate.
During this period of reperfusion, the inferior vena caval anastomosis followed by superior vena cava
anastomosis is performed using 4-0 Prolene continuous sutures. These anastomoses are performed in such a
way that endocardium is attached to endocardium in an everting manner. This technique minimizes the risk of
clot formation.
Narrowing of Caval Anastomosis
Suturing of the cavae should be done carefully to avoid narrowing or purse-stinging of the anastomosis, which
could complicate future endomyocardial biopsies.
This allows for direct measurement of left ventricular filling pressures during the immediate postoperative period.
A left atrial line is placed through the right superior pulmonary vein and secured in place with two pledgeted
Prolene sutures. The patient is then gradually weaned off cardiopulmonary bypass. Transesophageal
echocardiography is always used to assess both right ventricular and left ventricular function during the weaning
process.
Trapped Left Atrial Line
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After securing the left atrial line, it is important to pull on the catheter to ensure that it can be removed easily in
the postoperative period.
Training the Right Ventricle
Preexisting pulmonary hypertension and the effects of cardiopulmonary bypass on pulmonary vascular
resistance may give rise to perioperative right ventricular dysfunction, following heart transplantation. To
minimize the risk of right ventricular dysfunction and to “train” the right ventricle of the donor heart, we use a
segmental strategy in weaning cardiopulmonary bypass. This entails maintaining the systemic perfusion
pressure while at the same time reducing the right ventricular afterload. The technique involves leaving the
pulmonary artery anastomosis suture line untied and snared. A sucker with 3/4 in. tubing (to minimize the risk of
hemolysis) is inserted into the pulmonary artery and placed on suction at approximately 1 L per minute. The
systemic perfusion pressure is maintained at 60 mm Hg or above by the perfusionist. If the donor right ventricular
function remains stable with acceptable central venous pressure, the venting of the pulmonary artery is slowly
decreased and the suction tubing is removed. The pulmonary artery suture line is tied. This “segmental weaning
protocol” has been associated with a low incidence of postoperative right ventricular dysfunction.
Postoperative Hypoxemia
Persistence of a patent foramen ovale postoperatively can lead to right-to-left shunting and hypoxemia,
especially if the pulmonary vascular resistance is high.
Sinoatrial Node Injury
The sinoatrial node of the donor heart should not be manipulated during harvest or implantation to minimize the
risk of sinoatrial node injury.
12
Cardiac Tumors
BENIGN TUMORS
Myxoma
Primary tumors of the heart are very rare. More than half of the benign tumors are myxomas. Although they can
occur in any chamber of the heart, most myxomas arise from the interatrial septum and are seen most commonly
in the left atrium. In approximately 15% of patients, the tumor is located within the right atrium.
The diagnosis may be suggested by the patient's symptoms, often related to obstruction of flow through the
mitral orifice or systemic embolization. Echocardiography confirms the diagnosis.
Technique
The heart is exposed through a median sternotomy. The aorta is cannulated in the usual manner. The superior
and inferior venae cavae are both directly cannulated (see Chapter 2). This is accomplished with great care to
avoid manipulation of the atria.
Venous Cannulation through the Right Atrium
The introduction of large cannulas into the superior and inferior venae cavae through the right atrium may
dislodge tumor fragments as well as clutter the operative field during tumor resection. Therefore, direct
cannulation of both cavae is always preferred.
The aorta is clamped, and the heart is arrested with cold blood cardioplegia administered into the aortic root (see
Chapter 3). Previously placed snares around both venae cavae are snugged down on the venous cannulas. An
oblique incision is begun on the right superior pulmonary vein with a long-handled no. 15 blade. The opening is
extended obliquely across the right atrial wall. Two small retractors are placed on the atriotomy edges to expose
the right atrial cavity, interatrial septum, and any right atrial tumor that may exist (Fig. 12.1).
Right Atrial Myxoma
Myxomas occurring in the right atrium are usually bulky and may have a relatively wide base. The incision is now
extended across the interatrial septum, encircling the base of the tumor with an approximately 5-to-8-mm margin
of grossly normal septal wall. The tumor is excised and removed (Fig. 12.1).
Left Atrial Myxoma
Myxomas occurring in the left atrium are usually pedunculated and have a relatively small base attached to the
septum. The septal incision is extended across the septum under direct vision, and the base of the tumor is
excised, leaving a 5-to-8-mm margin of normal septal tissue (Fig. 12.2).
Artery to the Sinoatrial Node
The artery to the sinoatrial node traverses the atrial septum superiorly. Injury to this vessel may result in sick
sinus syndrome. The base of a myxoma in this vicinity should be shaved off.
Injury to the Atrioventricular Node
Dissection near the anterior aspect of the coronary sinus orifice may cause atrioventricular node injury with
resultant heart block.
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Myxomas can occasionally arise from the atrial wall. The base of the tumor is removed with a margin of
normal atrial wall. The resection need not be full thickness. The defect, if any, is approximated with fine Prolene
sutures or patched with a piece of autologous pericardium. To minimize the risk of local recurrence, we usually
apply a cryoprobe to the edges of the defect, especially when transmural resection cannot be done.
The septal defect is closed with a patch of autologous pericardium treated with glutaraldehyde or bovine
pericardium using a continuous suture of 4-0 Prolene. The opening on the superior pulmonary vein and the right
atriotomy are closed with a running 4-0 Prolene suture (Fig. 12.3). Deairing is carried out, and the aortic clamp is
removed.
Thick Atrial Septum
Occasionally, the atrial septum is thickened with hypertrophied muscle and fatty tissue. It is important to position
the pericardial patch on the endothelial surface of the left
atrial side of the septum to prevent possible embolism of fatty tissue or thrombus formation (Fig. 12.4).
FIG. 12.1 Exposure of a left atrial myxoma and its base. Inset: Exposure of a right atrial myxoma and its base.
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FIG. 12.2 Excision of a left atrial myxoma and its base with a generous margin of septal wall.
Rhabdomyoma
Rhabdomyomas arise from cardiac myocytes and are most commonly seen in infants and children. It is usually
part of the disease complex tuberous sclerosis. The gray-white tumor mass often may disappear totally with time.
Rhabdomyomas tend to grow as multiple tumors from the ventricular septum and cause obstruction of the inflow
and outflow tracts of both sides of the heart. The most common symptom is heart failure caused by obstruction of
a cardiac chamber or valve orifice.
FIG. 12.3 Closure of a septal defect with autologous pericardium.
Surgery is indicated before 1 year of age in patients without tuberous sclerosis when it may be possible to
enucleate the tumor. Unfortunately, symptomatic patients with tuberous sclerosis often have extensive, multiple
tumors and surgery has little to offer.
Fibroma
A fibroma arises from fibrous tissue cells as a single mass and is the second most common benign cardiac tumor.
The majority of fibromas occur in children. Classically, it presents as a solitary white whorley mass in either
ventricle, and frequently undergoes calcification. The symptoms are secondary to the obstruction of blood flow
through the
affected segment of the heart. If calcified, it may be appreciated on a chest x-ray. Echocardiography confirms the
presence and location of the mass.
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FIG. 12.4 Attaching a pericardial patch to the left atrial aspect of a thickened atrial septum.
Surgical excision is performed if the tumor is localized and can be enucleated. If the entire mass cannot be
removed, a debulking procedure can be palliative. Children with extensive fibromas may be considered for heart
transplant.
Papillary Fibroelastoma
Papillary fibroelastomas are solitary small tumors resembling vegetations. They are often seen arising from atrial
aspect of the mitral and tricuspid valves, and may involve chordal structures. Papillary fibroelastomas can also
arise from the ventricular surface of the aortic and pulmonary valves. These tumors are generally asymptomatic,
but they can obstruct flow and embolize. They may be found incidentally at the time of surgery or seen on
echocardiogram mimicking vegetations on the valves.
Because they can cause devastating complications, papillary fibroelastomas should be removed when
diagnosed. A conservative resection, allowing for a valve repair rather than replacement, should be performed.
Lipoma
Lipomas are generally localized discrete tumors. They can occur anywhere in the heart or on the pericardium.
Lipomas are generally asymptomatic. Large tumors causing significant symptoms should be resected. If a smaller
lipoma is noted incidentally during a cardiac procedure, it may be excised if it can be done without increasing the
risk of the surgery.
MALIGNANT TUMORS
Whether the tumor is primary or metastatic, the indication for surgery is determined by the tumor size, location,
and the absence of metastatic spread beyond the heart. If complete resection is possible, surgery results in
better palliation than radiation and/or chemotherapy alone. Complex left-sided cardiac malignancies are difficult
to adequately expose at the time of surgery. In these cases, cardiac autotransplantation may allow the surgeon
to completely remove the tumor. The patient's heart is explanted and the tumor is resected. Any resulting defects
are reconstructed, and the heart is then reimplanted.
Metastatic tumors are much more common than primary malignancies of the heart. Cardiac metastases are rarely
solitary. They commonly cause pericardial effusion. The surgical treatment of these patients is usually limited to
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