# 44 - 282 Atrial Myxoma and Other Cardiac Tumors

### 282 Atrial Myxoma and Other Cardiac Tumors

a normal or slightly enlarged heart. Pericardial calcification is most 
common in tuberculous pericarditis. Pericardial calcification may, 
however, occur in the absence of constriction, and constriction may 
occur without calcification.

Inasmuch as the common physical signs of cardiac disease (mur­
murs, cardiac enlargement) may be inconspicuous or absent in chronic 
constrictive pericarditis, hepatic enlargement and dysfunction asso­
ciated with jaundice and intractable ascites may lead to a mistaken 
diagnosis of hepatic cirrhosis. This error can be avoided if the neck 
veins are inspected and found to be distended with the characteristic 
waveform features.
PART 6
Disorders of the Cardiovascular System
The transthoracic echocardiogram often shows pericardial thicken­
ing, dilation of the inferior vena cava and hepatic veins, and a sharp halt 
to rapid left ventricular filling in early diastole, with normal ventricular 
systolic function and flattening of the left ventricular posterior wall. 
There is a distinctive pattern of transvalvular flow velocity on Doppler 
echocardiography (Fig. 281-4). During inspiration, there is an exagger­
ated reduction in blood flow velocity in the pulmonary veins and across 
the mitral valve, and a leftward shift of the ventricular septum; the 
opposite occurs during expiration. Diastolic flow velocity in the inferior 
vena cava into the right atrium and across the tricuspid valve increases 
in an exaggerated manner during inspiration and declines during 
expiration. However, echocardiography cannot definitively establish or 
exclude the diagnosis of constrictive pericarditis; CT and MRI are more 
accurate, with the latter useful in evaluating myocardial involvement.
■
■DIFFERENTIAL DIAGNOSIS
As with chronic constrictive pericarditis, cor pulmonale (Chap. 264) 
may be associated with marked systemic venous hypertension, little 
pulmonary congestion, a (left) heart that is not enlarged, and a para­
doxical pulse. However, in cor pulmonale, advanced parenchymal 
pulmonary disease is usually apparent and venous pressure falls dur­
ing inspiration (i.e., Kussmaul’s sign is negative). Tricuspid stenosis 
(Chap. 277) may also simulate chronic constrictive pericarditis with 
congestive hepatomegaly, splenomegaly, ascites, and venous distention. 
However, the characteristic murmur and that of accompanying mitral 
stenosis are usually present.
Because it can be corrected surgically, it is important to distin­
guish chronic constrictive pericarditis from restrictive cardiomyopathy 
(Chap. 266), which has a similar pathophysiologic underpinning (i.e., 
restriction of ventricular filling). The differentiating features are sum­
marized in Table 281-2. When a patient has progressive, disabling, and 
unresponsive congestive heart failure and displays any of the features of 
constrictive heart disease, Doppler echocardiography to record respira­
tory effects on transvalvular flow (Fig. 281-4) should be performed and 
an MRI or CT scan should be obtained to detect or exclude constrictive 
pericarditis because the latter is usually correctable.
TREATMENT
Constrictive Pericarditis
Pericardial resection is the only definitive treatment of constric­
tive pericarditis and should be as complete as possible. Coronary 
arteriography should be carried out preoperatively in patients aged 
>50 years to exclude accompanying coronary artery disease. The 
benefits derived from cardiac decortication are usually progressive 
over a period of months. The risk of this operation depends on the 
extent of penetration of the myocardium by the fibrotic and calcific 
process, the severity of myocardial atrophy, the extent of second­
ary impairment of hepatic and/or renal function, and the patient’s 
general condition. Operative mortality is in the range of 5–10% 
even in experienced centers; the patients with the most severe dis­
ease, especially secondary to radiation therapy, are at highest risk. 
Therefore, surgical treatment should, if possible, be carried out as 
early as possible.
Subacute Effusive-Constrictive Pericarditis 
This form of 
pericardial disease is characterized by the combination of a tense effu­
sion in the pericardial space and constriction of the heart by thickened 

pericardium. As such, it shares a number of features with both chronic 
pericardial effusion producing cardiac compression and with pericar­
dial constriction. It may be caused by tuberculosis (see below), multiple 
attacks of acute idiopathic pericarditis, radiation, traumatic pericardi­
tis, renal failure, scleroderma, and neoplasms. The heart is generally 
enlarged, and a paradoxical pulse is usually present. After pericardio­
centesis, the physiologic findings may change from those of cardiac 
tamponade to those of pericardial constriction. Furthermore, the intra­
pericardial pressure and the central venous pressure may decline, but 
not to normal. The diagnosis can be established by pericardiocentesis 
followed by pericardial biopsy. Wide excision of both the visceral and 
parietal pericardium is usually effective therapy.
Tuberculous Pericardial Disease 
This chronic infection is a 
common cause of chronic pericardial effusion, especially in the 
developing world where active tuberculosis and HIV are endemic. 
Tuberculous pericarditis may present as pericardial effusion, chronic 
constrictive pericarditis, or subacute effusive-constrictive pericarditis 
(see above). The clinical picture is that of a chronic, systemic illness 
in a patient with pericardial effusion. It is important to consider this 
diagnosis in a patient with known tuberculosis, with HIV, and with 
fever, chest pain, weight loss, and enlargement of the cardiac silhouette 
of undetermined origin. If the etiology of chronic pericardial effusion 
remains obscure despite detailed analysis including culture of the peri­
cardial fluid, a pericardial biopsy, preferably by a limited thoracotomy, 
should be performed. If definitive evidence is still lacking but the speci­
men shows granulomas with caseation, antituberculous chemotherapy 
(Chap. 183) is indicated.
If the biopsy specimen shows a thickened pericardium after 
2–4 weeks of antituberculous therapy, pericardiectomy should be per­
formed to prevent the development of constriction. Tubercular cardiac 
constriction should be treated surgically while the patient is receiving 
antituberculous chemotherapy.
■
■FURTHER READING
Arula S, Madsen N: Management of acute pericarditis. Curr Opin 
Caradiol 38:364, 2023.
Bayes-Coenis A et al: Colchicine in pericarditis. Eur Heart J 38:1706, 
2017.
Garcia MJ: Constrictive pericarditis versus restrictive cardiomyopa­
thy? J Am Coll Cardiol 67:2061, 2016.
Imazio M et al: New developments in the management of recurrent 
pericarditis. Can J Cardiol 2023.
Janus SE, Hoit BD: Effusive-constrictive pericarditis in the 
spectrum of pericardial comprehensive syndromes. Heart 
15:heartjnl-2020-316664, 2021.
LeWinter MM: Acute pericarditis. N Engl J Med 371:2410, 2014.
Mircanda WR, Oh JK: Effusive-constrictive pericarditis. Cardiol Clin 
3:551, 2017.
Vistarini N et al: Pericardiectomy for constrictive pericarditis. Ann 
Thorac Surg 100:107, 2015.
Welch TD: Constrictive pericarditis: Diagnosis, management, and 
clinical outcomes. Heart 104:725, 2018.
Stephen Tsaur, Eric H. Awtry

Atrial Myxoma and 

Other Cardiac Tumors
Cardiac tumors can be broadly classified into those that arise primar­
ily in the heart and those that reflect metastatic disease from a distant 
primary source. Primary cardiac tumors can be further divided into 
those that are pathologically benign and those that are malignant.

TABLE 282-1  Imaging Modalities and Their Utility in the Evaluation of 
Cardiac Tumors
MODALITY
UTILITY IN CARDIAC TUMOR EVALUATION
Transthoracic 

echocardiography (TTE) 
(including two-dimensional, 
three-dimensional, and contrast)
Assessment of tumor location and size and its 
impact on adjacent structures (e.g., valves, 
pericardium).
Transesophageal 
echocardiography (TEE)
Improved tumor characterization and spatial 
resolution compared with TTE. May aid in 
determining surgical approach.
Cardiac magnetic resonance 
imaging (MRI) with gadolinium 
contrast
Improved tissue characterization, definition of 
tumor size, and identification of local invasion 
when compared with TTE or TEE. May 
differentiate tumor from thrombus.
Gated cardiac computed 
tomography (CT)
Provides anatomic assessment and tissue 
characterization of the tumor. Useful when 
patients cannot tolerate MRI or when 
MRI is not feasible (e.g., patients with 
implantable cardiac devices). Allows for 
better assessment of calcified lesions and 
evaluation of extracardiac tumor involvement.
Nuclear imaging (including 
18F-fluorodeoxyglucose positron 
emission tomography [FDG-PET])
Definition of extracardiac disease. May 
be useful in diagnosis of certain cardiac 
tumors (e.g., neuroendocrine tumors), but 
assessment of smaller tumors may be limited 
by surrounding myocardial FDG uptake.
Overall, primary cardiac tumors are relatively uncommon, whereas 
secondary involvement of the heart or pericardium occurs in as many 
as 20% of patients with end-stage metastatic cancer. While patients 
with cardiac tumors may present with a variety of symptoms, many 
patients are asymptomatic at the time of diagnosis, with the tumor 
being identified incidentally on imaging studies performed for other 
reasons. Cardiac tumors need to be differentiated from other cardiac 
masses such as vegetation, thrombus, inflammatory myofibroblastic 
tumors, or myocardial hypertrophy. Echocardiography is usually the 
initial imaging modality used to evaluate cardiac tumors; however, a 
variety of imaging modalities are now available, and a multimodality 
approach is often necessary for accurate diagnosis and clarification of 
treatment options (Table 282-1). When diagnosis is uncertain after 
echocardiography, cardiac magnetic resonance imaging (MRI) is often 
useful to help further differentiate lesions. Imaging characteristics, 
including size, location, presence of myocardial infiltration, and first 
pass perfusion of gadolinium contrast agents, can help differentiate 
benign from malignant tumors. However, tissue histology remains the 
gold standard for diagnosis of cardiac tumors.
■
■PRIMARY TUMORS
Primary tumors of the heart are rare, occurring in ~1 in 2000 patients 
in autopsy series. Approximately three-quarters are histologically 
benign, the majority of which are myxomas. Malignant tumors, almost 
all of which are sarcomas, account for 25% of primary cardiac tumors. 
All cardiac tumors, regardless of pathologic type, have the potential to 
cause life-threatening complications. Many tumors are now surgically 
curable; thus, early diagnosis is imperative.
Clinical Presentation  
Cardiac tumors may present with a wide 
array of cardiac and noncardiac manifestations. These manifestations, 
which depend in large part on the location and size of the tumor as well 
as its impact on surrounding cardiac structures, are often nonspecific 
features of more common forms of heart disease, and include chest 
pain, syncope, congestive heart failure (CHF), murmurs, arrhythmias, 
conduction disturbances, pericardial effusion, and pericardial tampon­
ade. Additionally, embolic phenomena and constitutional symptoms 
may occur.
Myxoma  
Myxomas are the most common type of primary cardiac 
tumor in adults, accounting for one-third to one-half of all cases at 
postmortem examination, and approximately three-quarters of the 
tumors treated surgically. They occur at all ages most commonly in the 

third through sixth decades, with a female predilection. Approximately 
90% of myxomas are sporadic; the remainder are familial with autoso­
mal dominant transmission. The familial variety often occurs as part 
of a syndrome complex (Carney complex) that includes (1) myxomas 
(cardiac, skin, and/or breast), (2) lentigines and/or pigmented nevi, 
and (3) endocrine overactivity (primary nodular adrenal cortical dis­
ease with or without Cushing’s syndrome, testicular tumors, and/or 
pituitary adenomas with gigantism or acromegaly). The genetic basis of 
this complex has not been elucidated completely; however, inactivating 
mutations in the tumor-suppressor gene PRKAR1A, which encodes the 
protein kinase A type I-α regulatory subunit, have been identified in 
~70% of patients with Carney complex.

CHAPTER 282
Atrial Myxoma and Other Cardiac Tumors 
Pathologically, myxomas are gelatinous structures that consist of 
myxoma cells embedded in a stroma rich in glycosaminoglycans. 
Most sporadic tumors are solitary, arise from the interatrial septum 
in the vicinity of the fossa ovalis (particularly in the left atrium), and 
are often pedunculated on a fibrovascular stalk. In contrast, familial 
or syndromic tumors tend to occur in younger individuals, are often 
multiple, may be ventricular in location, and are more likely to recur 
after initial resection.
Myxomas commonly present with obstructive signs and symptoms. 
The most common clinical presentation mimics that of mitral valve dis­
ease: either stenosis owing to tumor prolapse into the mitral orifice or 
regurgitation resulting from tumor-induced valvular trauma or distor­
tion. Ventricular myxomas may cause outflow tract obstruction similar 
to that caused by subaortic or subpulmonic stenosis. The symptoms 
and signs of myxoma may be sudden in onset or positional in nature, 
owing to the effects of gravity on tumor position. A characteristic lowpitched sound, a “tumor plop,” may be appreciated on auscultation 
during early or mid-diastole and is thought to result from the impact 
of the tumor against the mitral valve or ventricular wall. Myxomas 
also may present with peripheral or pulmonary embolic phenomenon 
(resulting from embolization of tumor fragments or tumor-associated 
thrombus) or with constitutional signs and symptoms, including fever, 
weight loss, cachexia, malaise, arthralgias, rash, digital clubbing, and 
Raynaud’s phenomenon. These constitutional symptoms are likely the 
result of cytokines (e.g., interleukin 6) secreted by the myxoma. Labo­
ratory abnormalities, such as hypergammaglobulinemia, anemia, poly­
cythemia, leukocytosis, thrombocytopenia or thrombocytosis, elevated 
erythrocyte sedimentation rate, and elevated C-reactive protein level 
are often present. These features account for the frequent misdiagnosis 
of patients with myxomas as having endocarditis, collagen vascular 
disease, or a paraneoplastic syndrome.
Two-dimensional and three-dimensional transthoracic and/or 
transesophageal echocardiography are useful in the diagnosis of 
cardiac myxoma and allow for assessment of tumor size and deter­
mination of the site of tumor attachment, both of which are impor­
tant considerations in the planning of surgical excision (Fig. 282-1). 
A
B
FIGURE 282-1  Transthoracic echocardiogram demonstrating a large atrial 
myxoma. The myxoma (Myx) fills the entire left atrium in systole (A) and prolapses 
across the mitral valve and into the left ventricle (LV) during diastole (B). RA, right 
atrium; RV, right ventricle. (Courtesy of Dr. Michael Tsang; with permission.)

PART 6
Disorders of the Cardiovascular System
FIGURE 282-2  Cardiac magnetic resonance imaging demonstrating a rounded 
mass (M) within the left atrium (LA). Pathologic evaluation at the time of surgery 
revealed it to be an atrial myxoma. LV, left ventricle; RA, right atrium; RV, right 
ventricle.
Computed tomography (CT) and MRI may provide important addi­
tional information regarding size, shape, composition, and surface 
characteristics of the tumor (Fig. 282-2).
Although cardiac catheterization and angiography were previously 
performed routinely before tumor resection, they no longer are con­
sidered mandatory when adequate noninvasive information is avail­
able and other cardiac disorders (e.g., coronary artery disease) are not 
considered likely. Additionally, catheterization of the chamber from 
which the tumor arises carries the risk of tumor embolization. Because 
myxomas may be familial, echocardiographic screening of first-degree 
relatives is appropriate, particularly if the patient is young and has 
multiple tumors or features of a myxoma syndrome.
TREATMENT
Myxoma
Surgical excision using cardiopulmonary bypass is indicated regard­
less of tumor size and is generally curative. Myxomas recur in 
12–22% of familial cases but in only 1–2% of sporadic cases. Tumor 
recurrence most likely results from multifocal lesions in the former 
setting and incomplete tumor resection in the latter.
Other Benign Tumors  
Cardiac lipomas, although relatively com­
mon, are usually incidental findings at postmortem examination; 
however, they may grow as large as 15 cm, may present as an abnor­
mality of the cardiac silhouette on chest x-ray, and should be resected 
if they produce symptoms owing to mechanical interference with 
cardiac function, arrhythmias, or conduction disturbances. Papillary 
fibroelastomas are friable tumors with frond-like projections that are 
usually solitary and are the most common tumors of the cardiac valves. 
Although usually clinically silent, they can cause valve dysfunction and 
may embolize distally, resulting in transient ischemic attacks, stroke, 
or myocardial infarction. In general, these tumors should be resected 
even when asymptomatic, although a more conservative approach may 
be considered for small, right-sided lesions. Rhabdomyomas and fibro­
mas are the most common cardiac tumors in infants and children and 
usually occur in the ventricles, where they may produce mechanical 
obstruction to blood flow, thereby mimicking valvular stenosis, CHF, 
restrictive or hypertrophic cardiomyopathy, or pericardial constriction. 
Rhabdomyomas are probably hamartomatous growths, are multiple in 

RA 
RV 
T
T
LV 
T
T
FIGURE 282-3  Transthoracic echocardiogram revealing multiple tumors (T) 
consistent with rhabdomyomas in a 1-day-old infant. The largest tumor (arrows) 
was located in the left antrioventricular groove and measured 2 cm × 2 cm. LV, left 
ventricle; RA, right atrium; RV, right ventricle.
90% of cases, occur in ~50% of children with tuberous sclerosis, and 
are associated with mutations in the tumor-suppressor genes TSC1 and 
TSC2 (Fig. 282-3). These tumors have a tendency to regress completely 
or partially; only tumors that cause obstruction require surgical resec­
tion. Fibromas are usually single, universally ventricular in location, 
often calcified, and may be associated with mutations in the tumorsuppressor gene PTCH1. Fibromas tend to grow and cause arrhythmias 
and obstructive symptoms and should be completely resected when 
possible. Paragangliomas are rare chromaffin cell tumors that represent 
extra-adrenal pheochromocytomas. Most are located in the roof of the 
left atrium and can be identified on cardiac CT or MRI or with nuclear 
scanning using 131I-metaiodobenzylguanidine. They are highly vascu­
lar and may be hormonally active, resulting in uncontrolled hyperten­
sion. Extensive surgical resection is usually required. Hemangiomas 
and mesotheliomas are generally small tumors, most often intramyo­
cardial in location, and may cause atrioventricular (AV) conduction 
disturbances and even sudden death as a result of their propensity to 
develop in the region of the AV node. Other benign tumors arising 
from the heart include teratoma, chemodectoma, neurilemoma, and 
granular cell myoblastoma.
Malignant Tumors  
Almost all malignant primary cardiac tumors are 
sarcomas, which may be of several histologic types; angiosarcomas are 
the most common type in adults, whereas rhabdomyosarcomas are the 
most common type in children. In general, sarcomas are characterized 
by rapid progression that culminates in the patient’s death within weeks 
to months from the time of presentation as a result of hemodynamic 
compromise, local invasion, or distant metastases. Almost one-third 
are metastatic at the time of initial diagnosis, usually involving the 
lungs. Sarcomas commonly involve the right side of the heart, are rap­
idly growing, frequently invade the pericardial space, and may obstruct 
the cardiac chambers or venae cavae. Sarcomas also may occur on 
the left side of the heart and may be mistaken for myxomas. Isolated 
cardiac lymphomas have been rarely described but more commonly 
occur in the context of systemic disease. They are more common in 
men and in the elderly; usually involve the right heart; may present 
with arrhythmias, syncope, CHF, or constitutional symptoms; and are 
usually of the large B-cell type.
TREATMENT
Malignant Tumors
The optimal therapy for cardiac sarcoma is complete resection, 
often with neoadjuvant and postoperative chemotherapy; however, 
at the time of presentation, many of these tumors have spread 
too extensively to allow for surgical excision. Although there are