INTRODUCTION
Sarcoidosis is an inflammatory condition characterized by the presence
of non-caseating granulomas in affected organs and primarily affects
patients between the ages of 20 to 40 years.1,2 In the
United States, the incidence of sarcoidosis ranges from 10.9 to 35.5 per
100,000 in Caucasians and African Americans,
respectively.3 Based on autopsy findings, cardiac
involvement has been reported to occur in 25% of patients with systemic
sarcoidosis ,4 while imaging-based studies using
cardiac magnetic resonance (CMR) have demonstrated that up to 50% may
have cardiac lesions .2,5 While patients with cardiac
sarcoidosis (CS) can be asymptomatic, others can present with symptoms
due to conduction abnormalities, ventricular arrhythmias, and
cardiomyopathy.6 Very rarely, cardiac involvement or
even sudden cardiac death may be the first manifestation of systemic
sarcoidosis.7
Currently, all patients with biopsy-proven extra-cardiac sarcoidosis
routinely undergo screening for cardiac sarcoidosis with an
electrocardiogram (EKG), with or without an
echocardiogram.5 Advanced imaging modalities such as
(CMR) and 18F-Fluorodeoxyglucose–Positron Emission Tomography (FDG-PET)
are reserved for individuals suspected to have cardiac involvement based
on initial screening.5,8 The sensitivity of EKG for
detecting cardiac involvement is limited at 21 –
68%,6,9 while sensitivity for conventional
echocardiography ranges between 27% in asymptomatic individuals and
75% in the presence of symptoms or abnormal EKG
findings.9 Despite the demonstrated superiority of CMR
and FDG-PET in early diagnosis of CS, their role is limited by cost and
availability, making them inadequate initial screening
tests.10 Speckle tracking echocardiography (STE) is a
novel modality with a promising utility in predicting subclinical
myocardial involvement.11,12 The region of interest
(ROI) is marked with speckles that serve as stable acoustic markers to
trace tissue movement, irrespective of the angle of
interrogation.12 STE can evaluate cardiac function by
measuring left ventricular global longitudinal strain (LVGLS) and/or
global circumferential strain (GCS)10. We sought to
perform a meta-analysis of studies investigating the role of STE in
asymptomatic patients with proven extra-cardiac sarcoidosis and no known
cardiac involvement.