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1595
□ REVIEW ARTICLE □
Deterioration of Cardiac Function during the Progression ofCardiac Sarcoidosis: Diagnosis and Treatment
Fumio Terasaki and Nobukazu Ishizaka
Abstract
The cardiac involvement of sarcoidosis causes progressive heart failure symptoms and is a life-threatening
condition; thus, an early and appropriate diagnosis of this condition is crucial. On the other hand, the decline
in the cardiac function is rapid; therefore, patients usually have moderate-severe left ventricular dysfunction
when diagnosed with cardiac sarcoidosis, which may decrease the effectiveness of therapies. We herein report
three illustrative cases of heart failure due to cardiac sarcoidosis in patients who were or were not diagnosed
with preceding systemic sarcoidosis. We also discuss the currently available diagnostic modalities and possi-
ble biomarkers for the diagnosis of cardiac sarcoidosis.
Key words: cardiac sarcoidosis, cardiac function, congestive heart failure
(Intern Med 53: 1595-1605, 2014)(DOI: 10.2169/internalmedicine.53.2784)
Introduction
The clinical presentation of sarcoidosis with cardiac in-
volvement may depend on the extent and location of the
granulomatous processes (1, 2). The most frequent cardiac
manifestations of cardiac sarcoidosis (CS) include conduc-
tion disturbances and arrhythmias, sudden death and conges-
tive heart failure (CHF), the latter being reported in up to
30% of affected patients (3-9). Increased awareness, early
medical treatment, the use of pacemakers and implantable
cardioverter-defibrillators (ICDs) and cardiac resynchroniza-
tion therapy with ICD (CRTD) are changing the causes of
death in CS patients, with CHF becoming the most common
cause.
Yazaki et al. followed 95 CS patients for a mean period
of 68 months. Of these, 40 died, and 73% of the deaths
were associated with heart failure. The hearts of patients
with sarcoidosis-associated CHF often display a similar
morphology to that of patients with idiopathic dilated car-
diomyopathy (DCM). In a study of more than 100 patients
undergoing left ventriculoplasty for idiopathic DCM, we
found that 7% actually had CS, which had been undiag-
nosed prior to the cardiac symptoms (9). Yazaki et al. dem-
onstrated a five-year survival rate of 37% in patients with
sarcoidosis and 64% in patients with idiopathic DCM; both
groups had a similar New York Heart Association (NYHA)
functional class and left ventricular ejection fraction
(LVEF) (10). Therefore, the prognosis of CS may be worse
than that of idiopathic cardiomyopathy, and the onset and
severity of CHF may be a prognostic indicator of CS. On
the other hand, the prognosis of the patients with CS and
DCM has recently been improving due to the use of
evidence-based therapies and/or early detection of the dis-
ease. In a systematic review of the mortality data in patients
with CS, it was found that the five-year survival now ranges
from 75% to 100%, and that the extent of left ventricular
(LV) dysfunction is the strongest predictor of survival (11).
Considering that CS, when untreated, causes progressive
heart failure, which is frequently life-threatening, early de-
tection of the cardiac sarcoid involvement and the initiation
of appropriate therapies is mandatory; however, patients di-
agnosed with CS usually have advanced LV dysfunction at
the time of diagnosis of the CS (12). This is in part due to
the fact that cardiac dysfunction may occur suddenly and
progresses rapidly in the patients with systemic sarcoidosis,
who may not be followed-up very frequently as outpatients.
In the present study, we report three illustrative cases of
CHF and review the clinical issues associated with CS, with
special reference to the deterioration of the cardiac function
Department of Cardiology, Osaka Medical College, Japan
Received for publication February 27, 2014; Accepted for publication March 18, 2014
Correspondence to Dr. Fumio Terasaki, [email protected]
Intern Med 53: 1595-1605, 2014 DOI: 10.2169/internalmedicine.53.2784
1596
Figure 1. The temporal changes in the LV end-diastolic dimension (LVDd; vertical axis in A, mm) and LVEF (vertical axis in B, %) on the echocardiograms of the three patients. The horizontal axis represents years, and the 0 indicates the time at which cardiac sarcoid involvement was diagnosed. The pink dotted lines represent 55 mm LVDd in A and 50% LVEF in B, which are critical levels considered to indicate the progressive deterioration of the LV function in cardiac sarcoidosis.
10203040506070
-4 -3 -2 -1 0 1 2 3 4
Case 1
Case 2Case 3
Case 1
Case 2
Case 3
A B
Years Years
during progressive congestive cardiomyopathy. We also dis-
cuss the rate of the decrease in cardiac contractility in pa-
tients diagnosed or undiagnosed with systemic sarcoidosis
without known cardiac abnormalities prior to the emergence
of the cardiac manifestations.
Case Presentations
Case 1
A 51-year-old woman was admitted to our hospital with
sudden-onset symptoms of heart failure, which had started
about one month earlier. She reported no history of systemic
sarcoidosis. Echocardiography showed LV enlargement and
a diffusely decreased LVEF. She had undergone echocar-
diography 2.4 years prior, which showed a normal ejection
fraction (Fig. 1). Chest X-rays demonstrated cardiomegaly
and right hilar lymph node enlargement (Fig. 2A). An elec-
trocardiogram (ECG) showed normal sinus rhythm, albeit
with prolonged PQ intervals, incomplete right bundle branch
blocks, low voltages in the limb leads and ST-T abnormali-
ties (Fig. 2B). These changes in X-rays and ECG indicators
were not observed in the ECG obtained 2.4 years earlier, ex-
cept for slight PQ prolongation (Fig. 2C).
On admission, the patient’s plasma brain natriuretic pep-
tide (BNP) levels were markedly elevated (706 pg/mL).
Coronary angiography showed normal coronary arteries, and
left ventriculography showed hypokinesis of the anterior and
inferior walls (Fig. 2D, E). A histological examination of bi-
opsied endomyocardial samples revealed the infiltration of
mononuclear cells and enhanced fibrosis, although
sarcoidosis-like granulomatous formations were not detected
(Fig. 2F). The serum angiotensin-converting enzyme (ACE)
activity (17.0 IU/L) and soluble interleukin-2 receptor (sIL-2
R; 395 U/mL) levels were within the normal limits. There-
fore, we tested her for possible CS in further imaging ex-
aminations.
Cardiac magnetic resonance (CMR) imaging demonstrated
late gadolinium (Gd) enhancement (LGE) from the mid-wall
to the epicardial sites of the anteroseptal, anterolateral and
inferior walls of the left ventricle (Fig. 3A, D). T2-weighted
CMR showed high-intensity signal areas between the endo-
myocardial and mid-ventricular regions (Fig. 3B, E),
whereas 99m-technetium myocardial scintigraphy showed
perfusion defects on the basal areas and on the anterolateral
wall of the left ventricle (Fig. 3C, F). Subsequent 18F-
fluorodeoxyglucose positron emission tomography (18F-FDG
PET) showed increased nuclear uptake in the myocardium
and the hilar, para-aortic and subclavian lymph nodes
(Fig. 4A-C).
The cytology of fine-needle aspiration samples obtained
from the right supraclavicular lymph node clearly showed
multinucleated giant cells (Fig. 4D). To confirm the absence
of tuberculosis, nodal biopsies were examined, which re-
vealed noncaseating-epithelioid cell granulomas with multi-
nucleated giant cells, confirming the diagnosis of sarcoidosis
(Fig. 4E) (13). Following the diagnosis of systemic sarcoi-
dosis with cardiac involvement, prednisolone treatment was
initiated at a dose of 60 mg/day every other day; this dose
was gradually tapered to 20 mg/day every other day and has
been maintained.
Case 2
A 57-year-old woman with lung and lymph node sarcoi-
dosis that had been histologically diagnosed from biopsy
specimens two years earlier was transported by ambulance
to an emergency center after developing cardiogenic shock.
Chest X-rays demonstrated cardiomegaly and pulmonary
congestion. ECG analyses showed ventricular tachycardia
(VT; Fig. 5A), which was cured to sinus rhythm using elec-
trical cardioversion. Coronary angiography showed no sig-
nificant luminal stenosis, but left ventriculography showed
severe diffuse hypokinesis, particularly in the basal regions
(areas 1 and 5). The patient was transferred to our hospital
Intern Med 53: 1595-1605, 2014 DOI: 10.2169/internalmedicine.53.2784
1597
Figure 2. The chest X-ray, electrocardiogram (ECG), left ventriculography and cardiac biopsy findings for case 1. The chest X-ray showed cardiomegaly (cardiothoracic ratio of 60%) and enlarge-ment of the right hilar lymph nodes (A). The ECG showed normal sinus rhythms, PQ prolongation, incomplete right bundle branch block, low voltage in the limb leads and ST-T abnormalities (B). An ECG obtained 2.4 years earlier showed only slight PQ prolongation (C). Left ventriculography showed diffuse hypokinesis, particularly in the anterior (areas 1-2, arrows) and inferior walls (areas 3-4, arrow heads; D, end-diastolic phase; E, end-systolic phase). The histological evaluation of the endomyocardial biopsies showed the infiltration of mononuclear cells and enhanced fibrosis (F, scale bar indicates 50 μm).
A B C
D E F
the following day for further examination and treatment.
On admission, a chest X-ray demonstrated cardiomegaly
and an ECG showed normal sinus rhythm, with slight PQ
prolongation, complete right bundle branch block and occa-
sional premature ventricular contraction (Fig. 5C). Echocar-
diography showed LV enlargement and a diffusely decreased
LVEF (Fig. 5B), and the plasma BNP levels were elevated
(181 pg/mL). The echocardiographic data were almost nor-
mal, except for local hypokinesis at the anteroseptal LV wall
of the basal region, which had also been identified during
the examination performed two years earlier (Fig. 1, 5D).
The serum ACE activity (17.0 IU/L) was normal, but the
sIL-2R (771 U/mL) levels were elevated.
CMR imaging showed LGE on the epicardial site of the
left ventricle, but not on the lateral wall (Fig. 6A, B). T2-
weighted images showed hyperintense signals on the endo-
cardial and mid-wall sites of the anterolateral wall and inter-
ventricular septum (Fig. 6C), while 99m-technetium myocar-
dial scintigraphy showed perfusion defects in the basal parts
of the anteroseptal-inferoposterior wall of the left ventricle
(Fig. 6D). The previous 18F-FDG PET analyses had demon-
strated enhanced nuclear uptake in the lung and hilar and
mediastinal lymph nodes, but not in the heart. Cardiac biop-
sies were not obtained, because informed consent was not
obtained. An ICD was implanted and corticosteroid therapy
was initiated at a dose of 60 mg/day every other day; this
dose was gradually tapered to 5 mg/day every day and has
been maintained.
Case 3
In a previous study, we analyzed the clinical history of 54
patients diagnosed with systemic sarcoidosis (14). Among
these patients, two were not diagnosed with CS and were
eventually diagnosed with cardiac involvement during the
follow-up. One of these patients was a 69-year-old man with
systemic, but not cardiac, sarcoidosis confirmed by lymph
node biopsy. The patient had previously undergone periodic
follow-up with electrocardiography and echocardiography
for possible cardiac involvement. Although his LVEF was
within the normal range at the time of follow-up, it sud-
denly declined (Fig. 1). The 18F-FDG PET study showed in-
creased nuclear uptake in the left ventricle (Fig. 7A) and
CMR showed LGE, which was more prominent in the
epicardial regions (Fig. 7B). An endomyocardial biopsy
Intern Med 53: 1595-1605, 2014 DOI: 10.2169/internalmedicine.53.2784
1598
Figure 3. The cardiac magnetic resonance (CMR) imaging and 99m-technetium myocardial scin-tigraphy findings for case 1. Late gadolinium enhancement (LGE) was observed at the mid-wall-epi-cardial sites of the anteroseptal, anterolateral and inferior walls of the left ventricle (A and D, white arrows). The short axis shows the black-blood T2-weighted images demonstrating hyperintense sig-nals on the endocardial-mid-wall site of the anterolateral and inferior walls (B and E, yellow arrows). 99m-technetium myocardial scintigraphy showed perfusion defects in the basal part of the anterosep-tal-inferoseptal and the anterolateral wall of the left ventricle (C and F).
A
D
CB
E F
showed fibrotic degeneration with the infiltration of CD45-
positive lymphocytes and CD68-positive monocytes/macro-
phages, although granulomatous changes were not detected
(Fig. 7C). Sustained VT was documented, and after the di-
agnosis of cardiac sarcoid involvement, corticosteroid ther-
apy was initiated and a CRTD was implanted.
As indicated in Fig. 1, the CHF progressed rapidly within
only a few months or years in all three cases, sometimes in
association with ventricular tachyarrhythmias. The data from
the present cases suggest that a LV end-diastolic dimension
<55 mm and a LVEF <50% may be critical factors indicat-
ing the progressive deterioration of the LV function in CS
patients.
Strategies for Diagnosing Cardiac Sarcoidosis
CMR imaging
In cases with cardiac involvement of sarcoidosis, the
myocardium is replaced by fibrotic fibrogranulomatous tis-
sue. These fibrotic changes in the heart can be observed us-
ing magnetic resonance imaging (MRI) with the LGE tech-
nique. Previous studies demonstrated that characteristic LGE
patterns and locations are diagnostic of CS, and that CMR
imaging with LGE facilitates the prediction of the LV func-
tion. T2-weighted MRI has also been used to detect acute
inflammatory processes associated with myocardial sarcoido-
sis in CS patients (15). Therefore, T2-weighted sequences
may provide increased sensitivity for predicting progressive
deterioration in the cardiac function in CS patients.
In case 1 in the present study, CMR imaging demon-
strated LGE that may represent chronic myocardial dam-
age (16) from the mid-wall to the epicardial sites. In addi-
tion, T2-weighted CMR, which can demonstrate acute in-
flammation or edema (16), showed high-intensity signal ar-
eas between the endomyocardial and mid-ventricular re-
gions. These findings collectively suggested that the
inflammation-associated injury had migrated from the
epicardial region to the endomyocardial region.
Matoh et al. studied 12 sarcoidosis patients using Gd-
MRI, myocardial perfusion single photon-emission com-
puted tomography (SPECT) (17), gallium-67 citrate (Ga-67)
scintigraphy and/or 18F-FDG PET. LGE was observed in five
patients, and was positive in 39 (39%) of 100 LV segments.
LGE was distributed primarily from the mid- to the epimyo-
cardium, and the lack of perfusion defects on myocardial
perfusion SPECT was more prominent in less transmural
LGE segments. Two patients with diffuse LGE and one case
with focal LGE exhibited positive cardiac uptake on Ga-67
scintigraphy, while two other patients with focal LGE
showed cardiac uptake on 18F-FDG PET. The authors con-
cluded that LGE was useful for diagnosing CS and evaluat-
ing the cardiac function, suggesting that the distribution of
LGE from the mid- to the epi-myocardium is characteristic
Intern Med 53: 1595-1605, 2014 DOI: 10.2169/internalmedicine.53.2784
1599
Figure 4. The 18F-fluorodeoxyglucose positron emission tomography (18F-FDG PET) and cytohisto-logical findings of the lymph nodes from case 1. The frontal plane FDG PET/CT fusion images dem-onstrated abnormal uptake in the cervical and mediastinal lymph nodes and the anterior and inferior walls (A), horizontal plane, the interventricular septum and the lateral wall (B) of the left ventricle (arrows). The whole-body FDG PET maximum intensity projection image showed abnormal uptake into the general lymph nodes, including the right cervical lymph nodes, from which fine-needle aspi-ration cytology and biopsy specimens were obtained (C). The fine-needle aspiration cytology of the right supraclavicular lymph nodes; Papanicolaou staining of the aspirated specimens demonstrated the three-dimensional appearance of multinucleated giant cells (D). The staining of paraffin-embed-ded lymph node specimens from biopsies revealed noncaseating epithelioid cell granulomas with mul-tinucleated giant cells containing asteroid bodies, confirming the diagnosis of sarcoidosis (E). The scale bars in D and E indicate 50 μm.
A C D
B E
Figure 5. The ECG and echocardiogram findings for case 2. Ventricular tachycardia was docu-mented at an emergency center (A). Echocardiography performed at this admission showed LV en-largement (LV end-diastolic dimension, 59 mm) and a diffusely decreased LV ejection fraction of 38% (B). An ECG obtained on admission showed normal sinus rhythm, slight PQ prolongation and right bundle branch block (C). The echocardiographic findings obtained two years earlier were al-most normal, except that local hypokinesis in the anteroseptal LV wall of the basal region was ob-served (D).
A CB D
of CS, and that larger LGE areas correlate with poor LV
function.
Ichinose et al. analyzed the topographic localization of
myocardial lesions on CMR imaging and their relationships
Intern Med 53: 1595-1605, 2014 DOI: 10.2169/internalmedicine.53.2784
1600
Figure 6. The CMR and myocardial scintigraphy findings for case 2. Long- (A) and short- (B) axis CMR images showed LGE at the epicardial site of the mid-basal portions of the left ventricle (ar-rows), but not the lateral wall. The short axis showed black-blood T2-weighted images demonstrating hyperintense signals at the endocardial and mid-wall sites of the anterolateral-inferoseptal wall (C, arrows). 99m-technetium myocardial scintigraphy showed perfusion defects in the basal part of the anteroseptal-inferoposterior wall of the left ventricle (D).
A CB D
Figure 7. The 18F-FDG PET, CMR and cardiac biopsy findings for case 3. 18F-FDG PET showed abnormal uptake in the heart (arrows) and cervical, mediastinal and hilar lymph nodes (A). CMR showed LGE at the epicardial site of the anteroseptal-lateral wall of the left ventricle (B, arrows). The histological study of an endomyocardial biopsy sample showed fibrotic degeneration with the infiltra-tion of mononuclear cells (C, scale bar indicates 50 μm). Most mononuclear cells were CD45-positive lymphocytes or CD68-positive monocytes/macrophages (data not shown), although granulomatous changes were not detected.
A CB
with the plasma BNP levels and cardiac function parameters
in 10 CS patients. Myocardial hyperenhancement was sig-
nificantly more common in the subepicardial layers than in
the subendocardial layers (18). Moreover, the authors
showed a significant correlation between the global extent of
LGE and the plasma BNP levels, and a negative correlation
between the LV end-diastolic volume indices and LVEF in
CS patients. Therefore, the extent of myocardial lesions may
be related to the LV dysfunction and plasma BNP levels in
CS patients.
Watanabe et al. retrospectively evaluated 17 CS patients
who were diagnosed according to the 2006 revised guide-
lines of the Japanese Ministry of Health and Welfare (13)
and underwent CMR imaging (19). In that study, the LGEs
were located, and the relationship between the LGE and
LVEF characteristics and duration of sarcoidosis was evalu-
ated. While the LGE was most frequently found in the
subepicardial layer, the affected LGE segments were corre-
lated with the LVEF (r=-0.84, p<0.0001) and LV diastolic
volumes (r=0.88, p<0.0001). Transmural lesions were also
significantly more common in patients with an LVEF of
35% or lower than in those with an LVEF greater than 35%
(p=0.0004). All patients with an LVEF of 35% or lower had
both subepicardial and transmural lesions, and the affected
LGE segments were positively correlated with the duration
of sarcoidosis originating in the extracardiac organs (r=0.76,
p=0.005). The authors concluded that CMR imaging with
LGE facilitates the diagnosis of CS and predicts the LV
function.
Patel et al. performed an observational study of 152 pa-
tients with biopsy-identified extra-cardiac sarcoidosis (20),
no known cardiac sarcoidosis, and an LVEF of �50%. The
presence of LGE in the LV myocardium was considered to
be diagnostic for CS. Compared with patients without LGE,
those with LGE had higher heart rates (84±19 vs. 76±18
bpm, p=0.002), a greater prevalence of abnormal ECGs (76
vs. 31%, p<0.001), more diastolic dysfunction (67 vs. 33%,
p=0.05), a decreased right ventricular ejection fraction (49±8
Intern Med 53: 1595-1605, 2014 DOI: 10.2169/internalmedicine.53.2784
1601
vs. 55±6%, p=0.012), and evidence of non-sustained VT (33
vs. 6%). The authors concluded that patients with sarcoido-
sis and preserved systolic function commonly had myocar-
dial damage, which may increase the risk of ventricular
tachyarrhythmias.
18F-FDG PET
More recently, 18F-FDG PET has been increasingly used
for the evaluation and monitoring of CS patients (21-23).
Accordingly, 18F-FDG PET imaging plays a significant role
in the clinical diagnosis, assessment of disease activity,
monitoring of therapeutic responses and evaluation of the
prognoses of CS patients (24). In 18F-FDG PET imaging for
CS, the patterns of glucose metabolism and myocardial per-
fusion are known markers of inflammation. Whereas en-
hanced glucose metabolism with normal perfusion indicates
active inflammation, decreased perfusion with high glucose
metabolism represents advanced stage disease, and absent or
decreased perfusion with limited glucose metabolism indi-
cates end-stage CS. It should be noted that, for appropriate
interpretation of the PET images, the suppression of physi-
ological myocardial 18F-FDG PET uptake is crucial, which
can be achieved by fasting, dietary carbohydrate restriction
and the administration of heparin before the nuclear injec-
tion (25).
McArdle et al. (26) compared the locations and degrees
of FDG uptake in 20 CS patients with either advanced atrio-
ventricular block (AVB) or VT and compared the results
with those of seven CS patients without AVB or VT. Both
the mean LV standardized uptake (SUV) values and maxi-
mum SUV in the CS patients with VT were significantly
higher than those in CS patients with AVB (mean SUV: me-
dian VT, 5.33; range 4.7-9.35 vs. median AVB, 2.48; range
0.86-8.59; p=0.016; Max SUV: median VT, 11.07; range,
9.24-14.4 vs. median AVB, 5.63; range 3.42-15.71, p=0.005)
and those in control patients. The SUV values did not differ
significantly between the AVB patients and controls. The
receiver-operator characteristic (ROC) analyses were used to
identify patients with VT, and showed areas under the curve
(AUCs) of 0.93 and 0.895 for a mean LV SUV value of
>3.42 and a maximum SUV value of >8.56, respectively (p<
0.001). Moreover, the mean overall LV SUV value was cor-
related with the number of abnormal segments determined
by a visual analysis (Spearman’s coefficient =0.506, p=
0.006) and was negatively correlated with the resting LVEF
(Spearman’s coefficient =-0.42, p=0.024). In addition, the
mean EF was measured using gated rest PET perfusion
scanning and was found to be lower in VT patients than in
AVB patients (median VT, 33%; range 15-56 vs. median
AVB, 51%; range 18-71, p=0.082) and significantly lower in
VT patients than in clinically silent CS patients (p=0.0026).
These observations suggest that there is a relationship be-
tween the degree of abnormal FDG uptake and the clinical
presentation, particularly with reference to ventricular tachy-
arrhythmia and decreased LV function. Further prospective
studies are required to confirm these relationships.
Mehta et al. (27) evaluated 62 ambulatory patients with
sarcoidosis and diagnosed CS by assessing abnormalities de-
tected using CMR imaging or 18F-FDG PET. CS patients
were referred for risk stratification by electrophysiology
(EPS). Among the 62 patients examined, the prevalence of
CS was 39%, and CS patients were more likely to have ab-
normal Holter ECG recordings (50 vs. 3%, p<0.001) and
echocardiographic parameters (25 vs. 5%, p=0.02). The de-
gree of pulmonary impairment was not predictive of CS.
Two of the 17 patients analyzed using EPS had abnormal
test findings and received ICDs. Over a mean follow-up of
1.8 years, no patient died or exhibited ventricular arrhyth-
mias, and the authors concluded that the sarcoid lesions
identified on 18F-FDG PET are not predictive of arrhythmias
in patients with preserved cardiac function.
Matthews et al. (28) described a patient with CHF and
biopsy-diagnosed sarcoidosis whose imaging data were con-
sistent with cardiac involvement, as evidenced by extensive18F-FDG uptake into the ventricles and multiple focal areas
of myocardial hyperintense signals on T2-weighted CMR
images and corresponding areas of LGE. Significant clinical
improvements were observed after the initiation of medical
therapy for CHF and corticosteroids. Subsequent follow-up
CMR imaging studies performed three and nine months later
demonstrated improvements in the LVEF and the almost
complete disappearance of abnormal T2 signals, with persis-
tent LGE. However, the three- and 12-month 18F-FDG PET
analyses demonstrated complete resolution of all cardiac and
extracardiac sarcoid activity. Therefore, although both the
CMR and 18F-FDG PET analyses facilitated the diagnosis of
CS, only 18F-FDG PET imaging demonstrated serial assess-
ments that reflected the disease activity in response to ther-
apy.
Hybrid PET/MRI
Rischpler et al. reviewed a comparative summary of the
existing applications for hybrid PET/MRI in the field of car-
diology, and suggested potential cardiac applications that ex-
ploit the unique properties of the newly introduced com-
bined instrumentation (29). Integrated hybrid PET/MRI
analyses allow for the assessment of the quantity of affected
myocardium using LGE, facilitate the assessment of disease
stage and help in treatment decision-making. Moreover, this
technique may be used to assess CS-related inflammatory
cardiomyopathy.
White et al. reported a patient in whom simultaneous
PET/MRI was used to diagnose active CS (30). Interest-
ingly, intrinsic spatial regions of increased 18F-FDG uptake
were found in the subepicardial LGE zone, indicating possi-
ble fibrosis and suggesting inward migration of the inflam-
matory injury. Subsequently, 18F-FDG PET and cardiac MRI
were exploited as a hybrid technique for diagnosing active
CS. Therefore, using cardiac PET/MRI may be clinically
feasible and effective for the detection of inflammatory car-
diac disease.
Intern Med 53: 1595-1605, 2014 DOI: 10.2169/internalmedicine.53.2784
1602
Echocardiography
Kaderli et al. evaluated the LV function using conven-
tional echocardiography and tissue Doppler imaging in 55
patients with early stage pulmonary sarcoidosis without car-
diac involvement, and compared the findings with those of
22 healthy subjects. The isovolumic acceleration (IVA) is a
measure of LV contractility that is determined by non-
invasive tissue Doppler imaging (31). The IVA was lower in
patients with sarcoidosis than in healthy controls, and the ra-
tio of the myocardial pre-contraction time (PCTm) and con-
traction time (CTm) was higher at the septal annulus (p=
0.026). The IVA values in both the lateral and septal annuli
were also significantly lower in the sarcoidosis group than
in the control group. These observations may reflect sub-
clinical myocardial sarcoid involvement, particularly that of
the interventricular septum. The authors concluded that these
analyses may contribute to clinical decision-making by fa-
cilitating the predictions of cardiac involvement in patients
with pulmonary sarcoidosis.
Focardi et al. evaluated 69 patients with chronic sarcoido-
sis without suspected cardiac involvement and 26 control
subjects using echocardiography, and determined the preva-
lence of LV systolic and diastolic dysfunction in patients
with chronic sarcoidosis without clinical evidence of heart
disease (32). No significant differences were observed in the
atrial size, LV diameter, wall thickness, LVEF or endocar-
dial fractional shortening (FS) between the sarcoid and con-
trol patients. However, the sarcoid patients had lower mid-
wall fractional shortening (mFS). Taken together, these ob-
servations demonstrated the absence of LV systolic dysfunc-
tion, as evaluated by traditional echocardiographic methods,
in patients with chronic sarcoidosis, and an absence of any
relationship between LV diastolic dysfunction and sarcoido-
sis. Only the mFS was lower among sarcoid patients, par-
ticularly in those with a long disease history. Further analy-
ses are required to confirm the significance of this index as
a potential marker of cardiac involvement in patients with
chronic sarcoidosis.
Cytokines
Extensive myocardial sarcoid granulomatous infiltration
results in DCM and heart failure, which can be either sys-
tolic or diastolic in nature. However, studies of autopsy
hearts have demonstrated that granulomatous infiltration is
not distributed diffusely, but instead appears in patches.
Therefore, it is speculated that, in addition to direct injury
from granulomas with myocardial cell loss and interstitial fi-
brosis, other factors, such as proinflammatory cytokines,
may play a role in myocardial dysfunction, particularly in
the acute or subacute phase of CHF in CS patients.
The levels of inflammatory cytokines, including tumor ne-
crosis factor-alpha (TNF-α), interleukin-1β (IL-1β),
interleukin-6 (IL-6) and their soluble receptors, are report-
edly increased in CHF patients (33, 34). Inflammatory cy-
tokines may modulate the myocardial functions through a
variety of mechanisms, including stimulation of hypertrophy
and fibrosis through direct effects on cardiomyocytes and fi-
broblasts, the impairment of myocardial contractile function
through direct effects on intracellular calcium transport and
adrenergic receptor signaling, the induction of apoptosis and
increasing the expression of genes involved in myocardial
remodeling (35).
Type 1 helper T cell (Th1)-related cytokines
The expression of Th1-related cytokines is enhanced by
sarcoidosis. Therefore, we investigated the inflammatory cy-
tokine mRNA expression in the myocardia of 12 CS and 10
idiopathic DCM patients (36). These analyses showed sig-
nificantly enhanced expression of Th1-related cytokines,
such as IL-12p40, IFN-γ and IL-2, in CS patients, and myo-
cardial immunostaining demonstrated that the enhanced ex-
pression of IL-12 was confined to macrophages and giant
granuloma cells. These data suggest that the expression pat-
terns of the Th1-related cytokines IL-12 and IFN-γ may be
differentially diagnostic of cardiac dysfunction in patients
with idiopathic DCM and CS.
TNF-α
TNF-α is known to be a major proinflammatory cytokine
that controls the strength, effectiveness and duration of local
and systemic inflammatory reactions. Numerous studies
have confirmed high TNF-α production in cases with sarcoi-
dosis, and have shown an important role of TNF-α in granu-
loma formation (37-41). Moreover, mononuclear phagocytes,
such as mature macrophages, are responsible for the TNF-αsecretion in patients with sarcoidosis (42). In the study of
the inflammatory cytokines described above, TNF-α mRNA
was expressed in the myocardia of both CS and idiopathic
DCM patients, but it tended to be higher in the sarcoid
myocardia.
Takashige et al. (43) investigated TNFA (TNF-α) and
TNFB (lymphotoxin-alpha) gene polymorphisms in 26 CS
patients of Japanese origin. Significant increases in the
TNFA2 allele were found in the patient group, suggesting
that the TNFA gene is involved in the genetic susceptibility
to CS. Subsequently, HLA-DQB1*0601 was found to be the
allele most significantly associated with CS susceptibility,
and was more significantly increased compared with
TNFA2 (44). Kuroda et al. also analyzed single nucleotide
polymorphisms and showed that the TNF-α-857C/T poly-
morphism may affect the susceptibility to CS (45).
The chimeric monoclonal anti-TNF-α antibody, inflixi-
mab, has been approved for use in patients with rheumatoid
arthritis and Crohn’s disease. Case reports (46-50) have de-
scribed the success of infliximab in patients with sarcoidosis
refractory to conventional therapy. Although the benefits and
indications have not been established in patients with sarcoi-
dosis, these reports suggest that anti-TNF-α therapy may be
effective in patients with certain phenotypes.
Crouser et al. reported five consecutive patients with
CD4+ lymphopenia and assessed the clinical disease mani-
Intern Med 53: 1595-1605, 2014 DOI: 10.2169/internalmedicine.53.2784
1603
Table 1. Clinical Characteristics of Patients with CD4+ Lymphopenic Sarcoidosis*
Patient Age Gender Race Disease manifestations Clinical improvement post infliximab
S1 60 M W Lung, LN, hrt, sinus Lung a , hrt b , sinus c
S2 41 M AA Lung, LN, hrt, sinus Lung a , hrt b , sinus c
S3 65 F W Lung, LN, sinus Sinus c
S4 57 M W Lung, LN, skin Skin d
S5 58 M AA Lung, LN, hrt, eyes Lung a , hrt b , eyes e
AA: African American, F: female, hrt: heart; LN: lymph node, M: male, W: white.a A > 10% increase in FVC, total lung capacity, or diffusing capacity was observed.b Initial left ventricular ejection fraction was < 45% with 10 % subsequent increase.c Resolution of chronic sinus symptoms (recurrent infections, congestion) was reported.d Objective improvement in sarcoidosis-mediated skin rash was observed.e Resolution of uveitis was documented.
*Crouser ED, Lozanski G, Fox CC, et al. The CD4+ lymphopenic sarcoidosis phenotype is highly
therapy. Chest 137: 1433, 2010.
Table 2. Possible Biologic Markers of Sarcoidosis Activity*
Monocyte Origin Neutrophil associated
Angiotensin converting enzyme Collagenase
Lysozyme Elastase
Calcitriol
Kininase Extracellular matrix associated
Thermolysin-like metallopeptidase Procollagen III peptide
Neopterin Hyaluronan
Fibronectin
Lymphocyte associated Vitronectin
Soluble interleukin-2 receptors
Beta 2-microglobulin Others
Adenosin deaminase
*Baughman RP, Costabel U. Markers of sarcoidosis. In: Sarcoidosis.Baughman RP, Ed. Taylor & Francis, New York, 2006: 435-461.
CRP
ESR
Amyloid
festations and peripheral blood T-cell subsets before and af-
ter infliximab treatment (51). Significant increases in the ab-
solute peripheral blood lymphocyte and CD4+ T-cell counts
were observed, and improvements in the clinical disease
manifestations were demonstrated in all infliximab-treated
patients. The authors concluded that the presence of CD4+
lymphopenia identified a distinct sarcoidosis phenotype that
is particularly responsive to anti-TNF-α therapy. Interest-
ingly, in three of five patients, the initial LVEF values were
less than 45% and were subsequently increased by more
than 10% after anti-TNF-α therapy (Table 1).
Other biomarkers
Several biological markers, including ACE, lysozyme and
sIL-2R, have been recognized during assessments of sarcoi-
dosis activity (52) (Table 2). However, the sensitivity and
specificity of those biomarkers are often inadequate for CS,
which requires better biomarkers. Although several new
biomarkers of CS have been reported, none are genuinely
specific to CS. Therefore, integrative diagnoses require im-
aging and histological examinations, although the future di-
agnosis rates may be improved by the use of multiple
biomarkers.
Atrial natriuretic peptide (ANP) and BNP
In a study of 62 patients, Yasutake et al. showed a ten-
dency for there to be increased plasma ANP and BNP levels
in 27 CS patients, and demonstrated the utility of the ROC
analyses of these markers for distinguishing among high-
degree AVB, VT and CHF (53).
Myeloid-related protein complex (MRP 8/14)(S100A8/
A9)
MRP 8/14 is a member of the S100 family of
inflammation-related proteins and is expressed in activated
macrophages and granulocytes. We compared the serum lev-
els of MRP 8/14 in 30 normal subjects, 23 patients with idi-
opathic DCM, 25 sarcoid patients without CS and 10 pa-
tients with CS (54). The serum MRP 8/14 levels were only
significantly elevated in the CS patients, who had enhanced
immunohistochemical expression in macrophages and giant
cells of granulomas from myocardial tissues. Therefore, the
assessment of MRP 8/14 expression may facilitate the diag-
nosis of CS.
High-sensitive cardiac troponin T (hs-cTnT)
Baba et al. evaluated the sensitivity and specificity of hs-
cTnT, BNP, ACE, lysozyme, CMR and Ga-67 scintigraphy
using 18F-FDG PET data as an indicator of sarcoidosis activ-
ity in 12 CS patients (55). The data showed that the sensi-
tivity and specificity of hs-cTnT were 87.5% and 75%, re-
spectively, and the positive and negative predictive values
were 87.5% and 75%, respectively. These investigators con-
cluded that hs-cTnT was an excellent marker for evaluating
the disease activity in CS patients, with superior sensitivity
Intern Med 53: 1595-1605, 2014 DOI: 10.2169/internalmedicine.53.2784
1604
and negative predictive values and a good responsiveness to
steroid therapy.
High-sensitive cardiac troponin I (hs-cTnI)
Tanada et al. reported the case of a CS patient and deter-
mined the serum hs-cTnI levels over time. Both the serum
hs-cTnI and N-terminal proBNP (NT-proBNP) levels were
increased before the initiation of steroid therapy and de-
creased following treatment (56). While the level of NT-
proBNP was transiently elevated, possibly because of body
fluid retention associated with steroid therapy, the hs-cTnI
levels did not increase; they decreased with the proceeding
therapy. These data indicate that hs-cTnI may indicate myo-
cardial cytopathy in CS patients, and may have potential as
a biomarker of therapeutic responses.
Conclusion
The understanding of CS etiology and disease states has
advanced considerably in recent years, and the diagnostic
and treatment approaches have improved accordingly (57).
However, the temporal changes in cardiac function among
patients with sarcoidosis remain poorly characterized. CHF
usually progresses rapidly within a few weeks or months in
CS patients, and this is sometimes associated with conduc-
tion or rhythmic abnormalities that reflect gross myocardial
granulomatous infiltration. In addition, the influence of in-
flammatory cytokines, such as TNF-α, may be an important
factor in the pathogenesis of progressive congestive cardio-
myopathy in patients with CS. Biomarkers, including high-
sensitive cardiac troponins, may also be predictive of LV
dysfunction.
The observation of both an abnormal uptake on 18F-FDG
PET and abnormal CMR imaging (LGE, and particularly
hyperintensity on T2-weighted images) may therefore make
it clinically possible to detect active inflammation and to
thus predict a deteriorating LV function in CS patients.
However, because histopathological confirmation of myocar-
dial sarcoid lesions cannot be obtained in individual pa-
tients, it remains unclear whether subacute or chronic myo-
cardial sarcoid lesions are accurately reflected by these im-
aging modalities, which may also influence the LV function.
Finally, the establishment of optimal diagnostic and thera-
peutic strategies for CS patients and the preservation of their
LV function remains a challenge, and these topics warrant
thorough prospective multicenter trials.
The authors state that they have no Conflict of Interest (COI).
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