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Chapter 5 · Cardiology
Signs on Doppler Sonography
5 Doppler sonography should be performed for
patients with PE or patients with high risk of DVT who
show signs of respiratory distress (e.g., bedridden
patients).
5 DVT is diagnosed on Doppler sonography when an
intravenous echogenic material is detected (e.g.,
thrombus), the vein is distended and noncompressible
5
a
(most speci c and diagnostic sign), and there is loss of
color duplex signal within the vein. The thrombus
should be followed by the probe to detect its free
edge, and an observation of labile, freely moving
edge on real-time sonography should be reported. A
labile, free edge thrombus has a high risk of
embolization (. Fig. 5.1.6 ).
b
. Fig. 5.1.6 Sagittal, Doppler sonography ( a ) and Duplex ( b ) images of a patient with DVT show hypoechoic material within the external
iliac vein with free labile edge
Signs on CTA
5 PE is detected as complete filling defect with failure
to enhance the entire lumen (complete thrombosis).
The thrombosed vessel may be enlarged, and the
thrombus may appear hyperdense on non
contrast-enhanced images.
5 Partial filling defect of a pulmonary vessel
surrounded by areas of contrast material
enhancement (. Fig. 5.1.7 ) may be seen.
5 Pulmonary infarction is visualized as a wedge-shaped
area of lung parenchyma with high density located in
the periphery of the lung, with the base lying along
the pleura (. Fig. 5.1.5 ).
5 Areas of lobar atelectasis in PE may show contrast
enhancement.
5 Chronic PE is visualized as a peripheral intra-arterial
wall filling defect. Calcification of the organized
thrombus may be seen.
5 Saddle thrombus is a term used to describe a big
thrombus that abuts over the bifurcation of the main
pulmonary arteries (. Fig. 5.1.7 ).
5 Signs of right ventricular enlargement might be seen
in CT with displacement of the ventricular septum
toward the left ventricle, as a sign pulmonary
hypertension.
5 Areas of mosaic lung parenchyma pattern with
pruning of the pulmonary vessels may be seen
(. Fig. 5.1.8 ) .
5.1 · Acute Chest Pain
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a
199
b
5
. Fig. 5.1.7 Axial pulmonary CTA of two di erent patients ( a and b ) with pulmonary embolism (PE) shows saddle thrombus in ( a )
( arrowhead ) and distal complete thrombosis of the right pulmonary artery with partial thrombosis of the distal part of the left pulmonary
artery ( arrow in b )
Aortic Dissection
e term acute aortic syndrome is applied to multiple acute
chest pain presentations that are caused by thoracic aortic
diseases, including aortic dissection, aortic intramural hematoma (IMH), and penetrating atherosclerotic ulcer.
Aortic dissection is a condition characterized by separa-
tion of the aortic intima with presence of blood in a false
lumen between the intima and the medial layers of the aortic
wall.
e intima is the innermost layer of the aortic wall. Aortic
wall intimal tear starts typically at sites of highest intramural
pressure and wall tension. A er intimal tear, the blood ow
inside the tear dissects its way between the intima and the
. Fig. 5.1.8 Axial chest HRCT lung window illustration shows
mosaic pulmonary parenchymal pattern ( arrowheads ) and
pruning of the pulmonary arteries ( yellow circle )
media layer, creating a false lumen. e structure between
the true and the false lumen is called “intimal ap,” which is
the key diagnosis of aortic dissection on radiological examinations.
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Chapter 5 · Cardiology
e most common predisposing factors of aortic dissection are systemic hypertension, bicuspid aortic valve, aortic
coarctation, and Marfan’s syndrome. Patients typically present with sudden acute chest pain that is described as “tear-
ascending aorta, it is classi ed as type A. is type is managed medically; however, in the current era, even type B is
managed with endovascular stent across the origin of the
dissection.
ing” sensation and classically radiation to the back.
Debakey Classi cation
Aortic Dissection Is Classi ed According
totheStanford andDebakey Classi cations
Type I involves ascending aorta only.
Type II involves the ascending and the descending aorta.
Type III involves the descending aorta only.
Stanford Classi cation
5
Type A : this type involves the ascending aorta, and it is man-
aged surgically. is type carries the risk of spontaneous
rupture into the pericardium resulting in pericardial tamponade, or it can continue dissection to involve the coronary arteries (right coronary more than the le ). Patients
with this type can also develop aortic regurgitation (50 %
of cases).
Type B : this type involves the descending aorta only. e site
of dissection is typically just distal to the subclavian artery,
near the insertion of the ligamentum arteriosum. When
the dissection involves both the descending and the
Signs on Radiographs
There is mediastinal widening with obliteration of the aortic knuckle on plain radiographs.
D i erential Diagnoses andRelated Diseases
Vascular Ehlers–Danlos syndrome is a disease characterized
by joint hypermobility, skin abnormalities (e.g., easy bruising), fragility of intestinal and genitourinary organs, and vascular fragility leading to dissection or rupture of medium to
large muscular arteries. e disease has an autosomal dominant mode of inheritance and caused by mutation in collagen
type 3 gene (COL3A1). e dissection arises in vascular
Ehlers–Danlos syndrome that occurs typically without preceding aneurysm.
Signs on CTA
5 The key diagnostic nding in aortic dissection is
identi cation of the intimal ap, which appears as a
thin “line” of soft tissue within the aortic lumen
separating the false lumen from the true lumen
(. Fig. 5.1.9 ).
5 The true lumen shows higher enhancement than the
false lumen, because lling of the false lumen is slower
than the true lumen. Moreover, the false lumen may
show signs of intravascular thrombosis.
5 In the ascending aorta, the false lumen is typically the
more anterior lumen, while in the descending aorta,
it is typically the more posterior lumen.
5 Coronary artery dissection can be suspected when
the intimal flap is detected at or near the site of a
coronary ostium. When this sign is identified,
coronary CTA should be performed to detect the
extension of the dissection.
5 Pericardial hemorrhagic e usion may be detected as
highly attenuated uid within the pericardial space
(40–50 HU).
5.1 · Acute Chest Pain
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a
201
b
5
. Fig. 5.1.9 Axial cardiac CTA of two di erent patients with aortic dissection Stanford type A ( a ) and Stanford type B ( b ) shows the
classic intimal ap ( arrowheads ) separating the true from the false lumen
Aortic Intramural Hematoma
IMH is a condition characterized by rupture of the vasa vasorum, the network of vessels that supply the aorta itself, resulting in bleeding within the aortic wall, mostly within the
media layer.
IMH is clinically indistinguishable from aortic dissection.
Patients present with signs of acute aortic syndrome consisting of sudden chest pain that is radiating to the back or chest
depending on which part of the aorta is a ected. IMH
accounts for 10–30 % of cases of acute aortic syndrome, and it
may be caused by hypertension, blunt trauma, or penetrating
atherosclerotic ulcer. In contrast to aortic dissection, no intimal tear ap is identi ed in this condition. However, the
hematoma can progress into a true dissection if the aortic wall
continues to enlarge in thickness by the hematoma >5cm.
Signs on CTA
On contrast-enhanced scan, the aortic wall show a
crescentic area of wall thickening that may show high
attenuation if the bleeding is fresh. There is no intimal
ap (. Fig. 5.1.10 ).
. Fig. 5.1.10 Axial cardiac CTA shows posterior aortic arch
focal area of aortic wall thickening due to intramural hematoma
( arrowheads )
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Chapter 5 · Cardiology
Penetrating Atherosclerotic Ulcer
Penetrating atherosclerotic ulcer is a condition that results
from ulceration and break of an aortic atherosclerotic plaque
resulting in an intimal defect. is defect causes bleeding
within the aortic wall surrounding the ulcer, which will result
in IMH formation or pseudo-aortic aneurysm formation.
5.2 Diseases oftheGreat Vessels
e great vessels include the aorta, the superior and inferior
vena cava, the pulmonary artery, and the pulmonary veins.
ere are multiple medical conditions a ecting the great vessels
that require imaging to assess their complications, establish
their diagnosis, or monitor their therapy response. is topic
discusses some of the common medical conditions where radiology plays an important role in their diagnosis and assessment.
Signs on CTA
5
The scan will show an area of intimal defect within the
aorta with the formation of saccular pseudoaneurysm,
IMH, or periaortic mediastinal hematoma (. Fig. 5.1.11 ).
Thoracic Aortic Aneurysm
oracic aortic aneurysm (TAA) is a disease characterized by
dilatation of the wall of the aorta a ecting its three layers
(intima, media, and adventitia). In contrast, pseudo-aortic
aneurysm is a condition characterized by saccular dilatation
of the outer most layers of the aortic wall (media and/or
adventitia) with an intact inner wall layer (intima).
e most common cause of TAA is atherosclerosis, while
the most common cause of pseudo-aortic aneurysm is aortic
trauma violating the wall integrity. TAA originates in the
ascending aorta (50 %), descending aorta (40 %), and the aortic arch (10 %). In contrast, pseudo-aortic aneurysm usually
arises at three basic levels: the aortic root, the aortic isthmus,
and the aortic diaphragm.
Patients with TAA are typically in their 50s and 70s and
. Fig. 5.1.11 Axial cardiac CTA shows an area of aortic wall
ulceration of the descending thoracic aorta ( arrowhead ) with a
jet of bleeding into the aortic wall creating a periaortic
mediastinal hematoma ( arrowhead )
usually are asymptomatic. Up to 30 % of patients present with
complications due to TAA rupture. Pain or dysphagia due to
mass e ect over the adjacent mediastinal structure may be
seen uncommonly.
TAA expands at a rate of 0.5cm per year, with an increased
risk of rupture when it is >5cm in diameter. Patients with
Further Reading
Birchard KR. Acute aortic syndrome and acute traumatic
aortic injury. Semin Roentgenol. 2009. doi:10.1053/j.
ro.2008.10.002.
Castañer E, etal. Congenital and acquired pulmonary anom-
alies in the adult: radiologic overview. RadioGraphics.
2006;26:349–71.
Choe YH, etal. Comparison of MDCT and MRI in the detec-
tion and sizing of acute and chronic myocardial infarcts.
Eur J Radiol. 2008;66:292–9.
De Becker J, etal. Marfan and Marfan-like syndromes. Artery
Res. 2009;3:9–16.
H o mann U, etal. Cardiac CT in emergency department
patients with acute chest pain. RadioGraphics.
2006;26:963–80.
Jeudy J, etal. Nontraumatic thoracic injuries. Radiol Clin N
Am. 2006;44:273–93.
Oliver TB, etal. Spiral CT in acute non-cardiac chest pain.
Clin Radiol. 1999;54:38–45.
Winter-Muram HT, etal. Suspected acute pulmonary embo-
lism: evaluation with multi-detector row CT versus digital
subtraction pulmonary arteriography. Radiology.
2004;233:806–15.
TAA >6mm may present with spontaneous bleeding resulting in hemomediastinum or periaortic hematoma formation.
D i erential Diagnoses andRelated Diseases
5 Marfan’s syndrome is a disease characterized by ocular,
musculoskeletal, central nervous system, and
cardiovascular complications. Marfan’s syndrome
patients are known to su er from aortic root dilatation in
up to 80 % of cases. Patients may su er also from mitral
valve prolapse, or dissection of the aorta.
5 Loeys–Dietz syndrome is a disease characterized by aortic
aneurysm and dissection, with widespread arterial
tortuosity/aneurysms (seen in the thoracic aorta and neck
vessels mainly). e disease has an autosomal dominant
mode of inheritance. e disease is divided into two
types: type I Loeys–Dietz syndrome is characterized by
craniosynostosis, hypertelorism, bi d uvula, cle palate,
and/or arterial aneurysms and tortuosity; type II lacks the
hypertelorism, craniosynostosis, and cle palate.
5 Aortoduodenal syndrome is a very rare disease
characterized by obstruction of the duodenum by
aneurysmal dilatation of the abdominal aorta. Patients
classically present with abdominal pain, bilious vomiting,
and pulsatile abdominal mass.
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5
Signs on Radiographs
5 Aortic aneurysm is detected as a marked dilatation
of the aortic knuckle and mediastinal widening
(. Fig. 5.2.1 ).
5 Bronchial compression or erosion of the thoracic
vertebrae due to mass effect and chronic pressure
causing anterior scalloping may be seen on lateral
views.
5 Aortic wall calcification may be seen.
a
b
. Fig. 5.2.1 Posteroanterior chest radiograph of a patient
with thoracic aortic aneurysm (TAA) shows marked dilatation of
the aortic knuckle and the descending thoracic aorta
Signs on CTA
5 The thoracic aorta is considered dilated when its
diameter is >4cm (. Fig. 5.2.2 ).
5 Periaortic hematoma is detected as a hypodense
mass located in the mediastinum surrounding the
aorta. If the bleeding is fresh, the hematoma may
show high density (. Fig. 5.2.3 ).
5 Aortic wall calcification may be seen.
. Fig. 5.2.2 Axial thoracic CTA demonstrates TAA with fresh
blood leak into the mediastinum ( arrowhead )
. Fig. 5.2.3 Axial mediastinal window ( a ) and lung window ( b )
HRCT illustrations of a patient with pulmonary veno-occlusive
disease (PVOD) show right-sided heart chambers dilatation with
normal left heart chambers size. In ( b ), the lung parenchyma
shows bilateral di use linear interstitial lung pattern. Notice also
the small pericardial e usion in ( a ) ( arrowhead )
Pulmonary Hypertension
Pulmonary hypertension (PHT) is a disease characterized
hemodynamically by a mean pulmonary artery pressure
>25mmHg at rest (normal level, 10mmHg) or >30mmHg
during exercise (normal level, 15mmHg) with increased pulmonary vascular resistance.
Causes of PHT can be divided into two main groups: a
group with pathology is con ned to the arterial side of the
pulmonary circulation ( precapillary PHT ) and a second
group with pathology con ned to the venous circulation,
between the capillary bed and the le atrium ( postcapillary
PHT ). When the cause of the PHT is unknown, it is called
“idiopathic or primary” PHT, and when the cause of the PHT
is known, it called “secondary” PHT.
Causes ofPHT
5 Precapillary PHT : primary PHT, congenital heart defects
with le -to-right shunt, pulmonary embolism, parasites
(e.g., schistosomiasis), and talcosis (lung disease due to
talc crystals inhalation).
5 Postcapillary PHT : primary veno-occlusive disease,
mitral stenosis, and mediastinal brosis.
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Chapter 5 · Cardiology
Primary PHT is an idiopathic condition characterized by
precapillary PHT in the absence of an identi able cause.
a
Patients typically present with dyspnea (60 %), fatigue,
angina, cor pulmonale, and Raynaud’s phenomenon.
Typically, the patient is a young or middle-aged female. Risk
factors associated with primary PHT include portal hypertension, collagen vascular disease, pregnancy, and women
who use contraceptive pills.
Congenital heart defects associated with le -to-right
shunts predispose to PHT. Common defects with PHT
5
include atrial septal defects, ventricular septal defects, and
truncus arteriosus. Eisenmenger syndrome is an advanced
stage of PHT associated with congenital heart defects. e
disease is characterized by dyspnea, cyanosis, generalized
fatigue, and syncope. Patients with Eisenmenger syndrome
may die at a young age due to cardiac arrhythmias, which are
common features of this disease. Patients may also develop
paradoxical embolus passing from the right side of the heart
to the le through a heart defect.
b
Pulmonary veno-occlusive disease ( PVOD ) is a rare idio-
pathic disease characterized by postcapillary PHT, in the
presence of normal le atrial and le ventricular pressures.
PVOD is characterized by PHT, congestive heart failure, and
interstitial pulmonary edema with a normal wedge pressure
on cardiac catheterization. e pathological ndings in
PVOD show extensive and di use occlusion of pulmonary
veins by brous tissue, which may be loose edematous or
dense and sclerotic. Patients present with dyspnea, u-like
symptoms, and hemoptysis. It commonly a ects children
(30 % of cases), transplant patients, and pregnant women.
e disease may be misdiagnosed initially as interstitial lung
disease (
. Fig. 5.2.3 ) .
Signs on Chest Radiograph
5 The pulmonary vasculature diminishes in caliber as
it extends from the center toward the periphery
(pruning), with a mean width of the right
descending pulmonary artery >24mm (normal
<17mm in width).
5 Dilatation of the right and left main pulmonary
arteries (. Fig. 5.2.4 ).
5 Signs of right ventricular enlargement, right atrial
enlargement, or left atrial enlargement (mitral
stenosis).
5 POVD is suggested radiographically when the
radiograph shows signs of pulmonary PHT
associated with pulmonary interstitial edema and
normal-sized left atrium. The interstitial edema is
visualized as a diffuse linear interstitial pattern.
Mediastinal hilar lymphadenopathy may be
present.
. Fig. 5.2.4 Anteroposterior chest radiograph ( a ) and coronal
CTA ( b ) of a patient with primary pulmonary hypertension (PHT)
shows massively dilated pulmonary arteries ( arrowheads )
Signs on HRCT and CTA
5 PHT is diagnosed when the mean diameter of the
pulmonary artery is >29mm, with a segmental
artery-to-bronchus ration >1:1in three or four
pulmonary lobes (. Fig. 5.2.4 ).
5 The lung parenchyma shows mosaic pattern of lung
attenuation due to variation in parenchymal perfusion.
5 Arteriography shows symmetric enlargement of
the central arteries with tapering subsegmental
vessels toward the peripheries (pruning).
5 The right ventricle is considered dilated when the
ratio of its diameter to the diameter of the left
ventricle is greater than 1:1, with bowing of the
interventricular septum toward the left ventricle.
5.2 · Diseases oftheGreat Vessels
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205
5
5 Right ventricular hypertrophy is con rmed when the
myocardial wall thickness is >5mm (normally
<4mm).
5 Signs of pericardial thickness with small pericardial
effusion can be seen in a percentage of patients
with PHT without an obvious reason.
5 I n PVOD , classical CT finding shows the
combination of diffuse linear interstitial lung
pattern with or without mosaic ground glass
opacities, dilated pulmonary arteries, right-sided
heart chambers dilatation, mediastinal
lymphadenopathy, and pericardial or pleural
effusion, with normal-sized left atrium and
pulmonary veins (. Fig. 5.2.3 ) .
Coral Reef Aorta
Coral reef aorta is a rare condition characterized by excessive
calci cation of the suprarenal and juxtarenal aorta resembling the growth of hyperplastic bone, in the absence of
abnormalities in serum calcium levels.
Coral reef aorta can cause malignant hypertension due to
signi cant abdominal aortic lumen stenosis or renal artery
stenosis when it involves the renal arteries. Other complications include blue toe syndrome due to dislodged ulcerated
atherosclerotic plaques.
Signs on CT
On nonenhanced images, the aorta shows hard, irregular,
and gritty intra-aortic mass of calci cation. In contrast to
the typical appearance of atherosclerosis of the great
vessels, which follows the curve of the vessel wall, the
calci cation in coral reef aorta is irregular and protrudes
into the lumen (. Fig. 5.2.5 ).
Superior Vena Cava Syndrome
Superior vena cava syndrome (SVCS) is a disease characterized by a triad of edema of the upper torso, venous distension
of the neck, and chylothorax. SVCS arises due to extrinsic or
intrinsic SVC obstruction, causing disturbance of the venous
back ow from the head and neck region and formation of
venous collaterals.
Extrinsic causes of SVCS include bronchogenic carcinoma or lymphoma compressing the SVC (80 % of cases).
Intrinsic causes of SVCS are mostly due to thrombosis,
most commonly due to intravenous catheter use. Other
causes of intrinsic SVCS include thrombus propagation
from the subclavian veins to the SVC due to thoracic outlet
syndrome.
Patients with SVCS typically present with marked cyanosis and swelling involving the head and neck region and
the upper extremities, with development of super cial collateral circulation. Complications include pulmonary
embolism (5–35 % of cases), thrombophlebitis, sepsis, and
thrombus propagation into intracranial sinuses or veins. In
some patients, blood may be “sucked” into the thorax during inspiration, but because of the limited ventricular lling, the neck veins may become further distended
(Kussmaul’s sign).
In infants, SVCS has been linked with the formation of
hydrocephalus, called extraventricular obstructive hydroceph-
alus (EVOH). e mechanism of hydrocephalus is believed
to be caused by decrease in cerebrospinal uid absorption at
the level of the arachnoid granulation secondary to the elevated venous pressure. EVOH can be seen in up to 91 % in
infants with SVCS.Complications of EVOH include hemorrhagic infarction and seizures.
Signs on Chest Radiographs
5 Pleura effusion (chylothorax).
5 The chest may show the cause of SVCS if the
reason was obstruction from a mediastinal tumor.
5 Rib notching may present with long-standing SVC
obstruction.
. Fig. 5.2.5 Axial abdominal CT illustration demonstrates coral
reef aorta seen as di usely calci ed arterial wall with projection
of the calci ed plaques into the aortic lumen ( arrowhead )
Signs on Superior Vena Cavography
There is partial or complete SVC lling defect with
formation of numerous venous collaterals (. Fig. 5.2.6 ).
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Chapter 5 · Cardiology
Karmazyn N, etal. Neuroimaging ndings in neonates and
infants from superior vena cava obstruction a er cardiac
operation. Pediatr Radiol. 2002;32:806–10.
Rosenberg GD, etal. Blue toe syndrome from a “coral reef”
aorta. Ann Vasc Surg. 1995;9:561–4.
Rosenberger A, etal. Superior vena cava syndrome: a new
radiologic approach to diagnosis. Cardiovasc Intervent
Radiol. 1980;3:127–30.
Schulte K-M, etal. Coral reef aorta: a long-term study of 21
patients. Ann Vasc Surg. 2000;14:626–33.
5
Takagi H, et al. Aortoduodenal syndrome. J Vasc Surg.
2006;43:851.
5.3 Myocardial Diseases
(Cardiomyopathies)
Cardiomyopathies are a group of diseases with di erent etiologies, all characterized by cardiac muscle dysfunction.
Cardiomyopathies are an important cause of arrhythmias
. Fig. 5.2.6 Superior vena cava venography shows
occlusion of the superior vena cava (SVC) due to
thrombosis ( arrowhead )
Signs on Chest CT
5 Mediastinal masses (e.g., bronchogenic carcinoma)
can be found in cases of extrinsic SVC obstruction.
5 After contrast injection, partial or complete filling
defects representing SVC thrombosis can be seen
in cases of intrinsic SVC obstruction.
and sudden cardiac death in young patients. ree types of
cardiomyopathies have been described by the World Health
Organization (WHO):
5 Hypertrophic cardiomyopathy ( HCM ) is characterized by
inappropriate le ventricular hypertrophy, with
preservation of the myocardium contractility.
5 Dilated cardiomyopathy ( DCM ) is characterized by
ventricular dilatation with contractility dysfunction.
Most secondary causes of cardiomyopathies are related to
this type.
5 Restrictive cardiomyopathy ( RCM ) is characterized by
diastolic dysfunction and restricted contractility.
Signs on Brain CT
In infants with EVOH, brain CT may be normal in early
stages or show signs of ventricular dilatation due to
hydrocephalus.
Further Reading
Akpinar E, et al. PVOD suggested by MDCT and clinical
ndings in a pregnant woman. Emerg Radiol. 2008;
15:193–5.
Beghetti M, etal. Eisenmenger syndrome. A clinical perspec-
tive in a new therapeutic era of pulmonary arterial hypertension. JACC. 2009;53:733–40.
Deitch JS, etal. Abdominal aortic aneurysm causing duode-
nal obstruction: two case reports and review of the literature. J Vasc Surg. 2004;40:543–7.
Frazier AA, etal. Pulmonary vasculature: hypertension and
infarction. RadioGraphics. 2000;20:491–524.
Gotway MB, etal. oracic aorta imaging with multislice
CT.Radiol Clin N Am. 2003;41:521–43.
Johnson PT, etal. Loeyz-Dietz syndrome: MDCT angiogra-
phy ndings. AJR. 2007;189:W29–35.
Other uncommon forms of cardiomyopathies include athlete’s heart, arrhythmogenic right ventricular dysplasia (ARVD),
noncompaction cardiomyopathy (NCCM), and peripartum
cardiomyopathy. Each of the classic three forms and the uncommon forms of cardiomyopathies are discussed below.
Hypertrophic Cardiomyopathy
Primary HCM is a disease characterized by inappropriate
myocardial hypertrophy in the absence of a cause (e.g.,
hypertension). In contrast, secondary HCM can be seen due
to diseases of protein deposition (e.g., amyloidosis).
Cardiac muscle hypertrophy in HCM is described as
“concentric” or “eccentric.” Concentric heart hypertrophy
means increased heart muscle bulk and wall thickness, and it
is best assessed on cardiac MRI by looking at the heart thickness in the short-axis view. Eccentric heart hypertrophy means
general increase in the heart muscles with preservation of the
normal cardiac wall thickness (isometric).
Patients with HCM o en present with symptoms that
include ischemic cardiac pain and arrhythmias, although
most patients may be asymptomatic. HCM is the most common cause of sudden cardiac death in athletes. Up to 25 % of
HCM patients have le ventricle out ow tract (LVOT)
5.3 · Myocardial Diseases (Cardiomyopathies)
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obstruction due to the thickened interventricular septum.
Venturi e ect is a term used to describe LVOT obstruction by
hypertrophic interventricular septum during systole, which
causes retrograde jet ow toward the mitral valve, causing
anterior mitral valve lea et regurgitation.
Athlete’s heart is a physiological cardiac hypertrophy.
Sports are divided into endurance sports (e.g., weight li ing)
and dynamic sports (e.g., running). Endurance sports cause
concentric cardiac hypertrophy (<12mm) thickness, while
dynamic sports cause eccentric cardiac hypertrophy that may
reach (13mm) in thickness.
Di erentiation between athlete’s heart and HCM can be dif cult by imaging alone. However, evidences of bizarre electrocardiogram (ECG) patterns, female sex, abnormal le ventricular
lling, and marked le ventricular enlargement all favor
HCM.Moreover, athlete’s heart shows reduction in the heart
muscle wall thickness from 2 to 5mm a er a 3-month period of
athletic abstaining, a feature that is not seen in true HCM.
D i erential Diagnoses andRelated Diseases
5 Yamaguchi syndrome , also known as apical HCM , is a
disease characterized by HCM that is con ned to, or
located primarily in, the le ventricle (LV) apical region.
Up to 40 % of patients are asymptomatic. ECG leads
show characteristic deeply inverted T wave, which might
be mistaken for coronary ischemic disease.
5 Barth syndrome is an X-linked recessive disorder
characterized by HCM, neutropenia, skeletal myopathy,
growth delay, hypocholesterolemia, and urinary
excretion of 3-methylglutarate, 3-methylglutaconate, and
2- ethyldracrylate.
5 Romano–Ward syndrome is an autosomal dominant
disease characterized by long ECG QT interval, cardiac
arrhythmia, and occasional incidence of HCM.
5 Jervell and Lange-Nielsen syndrome is an autosomal
recessive disease characterized by long ECG QT interval,
cardiac arrhythmia, sensorineural hearing loss, syncopal
attacks evoked by emotional stress, and occasional HCM.
5 Abnormal, late (>10min) patchy contrast
enhancement of the hypertrophic muscles is
found in 79 % of patients of HCM, probably due to
small-vessel disease and ischemia.
5 Venturi effect is seen as an area of signal void and
mitral valve regurgitation with LVOT obstruction
on cine images during systole.
5 Yamaguchi syndrome shows hypertrophic left
ventricular apex, causing the left ventricular cavity to
exhibit characteristic “spade-like” con guration.
5 Athlete’s heart is visualized as mild increase in the
left ventricular myocardial wall thickness that does
not exceed 13mm in thickness on short-axis views.
There is no abnormal wall enhancement after
contrast injection.
a
b
207
5
Signs on Chest Radiographs
The heart size can be enlarged with signs of left
ventricular dilatation.
Signs on MRI
5 Normal LV end-diastolic septal wall thickness is
8.5–9.0mm. In athletes, the LV end-diastolic septal
wall thickness should not exceed >13mm in males
and >11mm in females. LV end-diastolic septal
wall thickness >15mm is definitely abnormal.
5 Disproportional ventricular wall hypertrophy with
end-diastolic septal wall thickness >15mm. The
interventricular septum is a ected in >70 % of
patients (. Fig. 5.3.1 ).
. Fig. 5.3.1 Four-chamber white blood cardiac MRI ( a ) and
two-chamber view ( b ) show concentric hypertrophic
cardiomyopathy (HCM). Notice the thickened chordae
tendineae in ( a )
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