A Case of Cardiac Sarcoidosis Presenting with a Low-level Elevation of Troponin: Case Report and Literature Review

Summary

This study reports an asymptomatic, untreated pulmonary sarcoidosis patient with normal routine cardiac screening, who was diagnosed with cardiac sarcoidosis via cardiac magnetic resonance (CMR) due to recurrent high-sensitivity cardiac troponin T(hs-cTnT) elevation. Routine hs-cTnT screening facilitates early detection of cardiac involvement, timely treatment, and improved prognosis.

Abstract

Cardiac sarcoidosis (CS) is a rare complication of systemic sarcoidosis, which can occur independently or concurrently with systemic sarcoidosis. The clinical manifestations range from asymptomatic myocardial granulomas to arrhythmias, heart failure, or cardiogenic sudden death, significantly increasing the mortality rate associated with sarcoidosis. Early diagnosis and treatment of CS is crucial, especially for patients with limited symptoms of systemic sarcoidosis. In patients with confirmed systemic sarcoidosis, cardiac sarcoidosis (CS) frequently exhibits a clinically silent phenotype, typically manifesting several years subsequent to the initial onset of systemic sarcoidosis manifestations. To date, no definitive evidence substantiates the utility of serum biomarkers for CS screening, and data regarding their efficacy in CS diagnosis and clinical management remain limited. We report a case of an asymptomatic, untreated patient with pulmonary sarcoidosis, who repeatedly had mild elevation of high-sensitivity cardiac troponin T(hs-cTnT), with no abnormalities in electrocardiogram or echocardiography. Eventually, Cardiac Magnetic Resonance (CMR) examination confirmed the diagnosis of cardiac sarcoidosis, and the patient's indicators improved after immunosuppressant treatment. We conducted a literature search to evaluate the effectiveness of hs-cTnT as a screening tool for CS, providing a reference for the management of CS in clinical practice.

Introduction

Sarcoidosis is a systemic granulomatous disease that can affect multiple organs, and its prevalence varies by region¹. In North America, the prevalence of sarcoidosis is estimated to be 141-160 cases per 100,000 people, with the highest incidence among Japanese people in Asia^1,2. Sex-related disparities in the cardiac sarcoidosis (CS) population are consistently documented, with ethnicity likely playing a contributing role. Notably, Japanese CS cohorts consistently report a higher prevalence in women, while earlier European and American studies uniformly demonstrate a male predominance<....

Protocol

This study is in accordance with the Declaration of Helsinki. The study was approved by the Medical Ethics Committee of the Fourth Affiliated Hospital of School of Medicine ,Zhejiang University (K2025173).

1. Patient selection

NOTE: Included in this study was a 47-year-old patient with a 3-year confirmed history of pulmonary sarcoidosis, undergoing reassessment of mediastinal lymph node enlargement found on follow-up CT.

1. Verify absence of acute systemic or cardiopulmonary symptoms such as fever, cough, chest tightness, or chest pain. Record demographic data (age, sex, BMI) and relevan....

Results

No arrhythmia signs were observed in the electrocardiogram (Figure 1). No abnormalities were found in the echocardiogram. The enhanced CT scan of the lungs indicated enlarged lymph nodes in the mediastinum and at the lung hilum, as well as pulmonary shadows adjacent to the two lung hilums (Figure 2). Bronchoscopy examination suggested enlarged lymph nodes in groups 7 and 4R (Figure 3). Histological examination of the biopsy specimen.......

Discussion

Cardiac sarcoidosis affects all layers of the heart, mainly affecting the myocardium, and is a serious complication of systemic sarcoidosis¹⁰. Approximately 5% of sarcoidosis patients have clinical manifestations of heart diseases, but autopsy studies suggest that the prevalence may be higher, ranging from 20% to 30%¹¹. People are increasingly recognizing that the heart of sarcoidosis patients is prone to being affected. Histological confirmation of CS is the gold standard .......

Materials

List of materials used in this article

Name	Company	Catalog Number	Comments
Elecsys Troponin T hs	Roche Diagnostics Gmbh	2025061700	Used for detecting high-sensitivity troponin levels
Gadopentetate Dimeglumine Injection	Guangzhou Kangchen Pharmaceutical Co., Ltd.	YBH05822024	Used for completing enhanced magnetic resonance examination
GE MAC 5500 HD system	GE Healthcare	MAC 5500 HD	High-performance digital ECG system with high-definition waveform and advanced analysis capabilities for clinical dia
Lohexol Injection	General Electric Pharmaceuticals (Shanghai) Co., Ltd.	1206945	Used for completing enhanced CT examination
Olympus BX53 microscope.	Olympus	BX53	A research-grade upright microscope for various techniques including brightfield, darkfield, fluorescence, and polarization. Commonly used in pathology and cell biology.
Olympus NA-201SX-4022	Olympus / Beckman Coulter*	AU480	A modular, medium-throughput clinical chemistry analyzer for routine tests like glucose, liver, and renal function. (*Note: Olympus clinical business was acquired by Beckman Coulter.)
Philips EPIQ 7C	Philips	EPIQ 7C	High-end cardiovascular ultrasound system with superior image quality and advanced quantification tools, primarily for echocardiography.
Roche Cobas e801 analyzer	Roche	cobas e 801	High-throughput, automated immunoassay module for tumor markers, hormones, infectious diseases. A core module of the cobas 8000 series.
Roche Elecsys platform	Roche	Elecsys	The brand name for Roche's electrochemiluminescence technology platform. The "catalog number" is specific to individual reagent tests.
Siemens MAGNETOM Avanto	Siemens Healthineers	MAGNETOM Avanto	A 1.5T MRI system known for high gradient performance, Tim (Total imaging matrix) coil technology, and broad clinical applications.
Siemens SOMATOM Definition Flash	Siemens Healthineers	SOMATOM Definition Flash	A dual-source CT scanner renowned for its extremely fast scanning speed ("Flash" spiral mode) and low radiation dose.