A case from CHEST 2024 shows that cardiac sarcoidosis should be considered in patients aged less than 65 who have unexplained high-grade atrioventricular block.
“Clinically significant cardiac sarcoidosis (CS) is estimated to be seen in 5% of sarcoidosis patients,” Manik Choudhary, MD, and colleagues wrote. “Patients may report non-specific symptoms such as chest pain, palpitations, bradycardia, dyspnea, syncope or peripheral edema.”
While CS is rare, it represents a potentially fatal presentation of sarcoidosis, the researchers noted.
Dr. Choudhary and colleagues presented a case study at CHEST 2024 to make the case for expanding the diagnosis differential for non-specific cardiac symptoms to include CS. The patient was a 61-year-old man with a medical history of high blood pressure, high cholesterol, and coronary artery disease (CAD).
Over the course of 4 months, he experienced worsening shortness of breath with exertion and bradycardia. Due to the CAD diagnosis, he was administered an outpatient stress test. The test was limited, as the patient experienced shortness of breath and dizziness, the stress test was stopped during early recovery because the patient was in complete atrioventricular block (AVB).
Following the test, he was sent home with a 14-day external loop recorder and later advised to seek further evaluation at the ED. When he arrived, his EKG showed sinus rhythm with complete AVB, as well as alternating junctional and ventricular escape rhythms. His ventricular rate was 34 beats per minute.
The patient’s lab work did not reveal any abnormalities. “[Thyroid-stimulating hormone] and [pro b-type natriuretic peptide] were unremarkable,” the researchers wrote. “[High sensitivity] troponin was 12ng/L and 13ng/L at 0 and 1 hours.”
There also weren’t any wall motion abnormalities seen in a bedside point-of-care ultrasound.
Treatment & Further Testing
Based on these results, he was started on intravenous ceftriaxone for Lyme disease, but serology revealed that wasn’t the cause of the symptoms, either. Dr. Choudhardy and colleagues conducted a CT scan of the patient’s chest, which showed mediastinal lymphadenopathy and multiple pulmonary nodules. The team also performed a transthoracic echocardiogram, “which noted preserved biventricular systolic function with an estimated right ventricular systolic pressure of 37 mmHg.”
A subsequent cardiac MRI revealed “patchy mid-myocardial enhancement along the inferoseptal basilar wall.” This is a non-specific finding that can indicate infectious, inflammatory, or infiltrative diseases, according to the researchers.
Based on the patient’s medical history and these findings, there was a strong suspicion for CS, so he was sent to surgery for a dual chamber implantable cardioverter-defibrillator placement.
The care team also performed an endobronchial ultrasound and fine needle aspiration of mediastinal lymph nodes. These tests didn’t reveal anything diagnostic, so the patient was discharged once it was medically appropriate.
Follow-Up & Broader Clinical Implications
At follow up, the patient underwent a fluorodeoxyglucose PET scan, which showed moderate to severe substrate uptake involving the myocardium. The patient and care team discussed these findings and ultimately chose to defer an endomyocardial biopsy. Instead, they decided to conduct an interdisciplinary evaluation for presumed sarcoidosis with CS.
This patient presented with AVB, which is the most common presentation of symptomatic CS for younger patients, according to the researchers. As a result, Dr. Choudhary and colleagues argue that unexplained high-grade AVB should raise suspicion for CS in patients under 65, making it an important differential diagnosis for non-specific cardiac symptoms.
“A multidisciplinary team approach is pivotal and is likely to aid with early diagnosis and management, improving patient outcomes,” the researchers wrote.
