Cardiovascular magnetic resonance imaging and clinical performance of somatostatin receptor positron emission tomography in cardiac sarcoidosis

Abstract

Aims: Cardiac affection constitutes a major limiting condition in systemic sarcoidosis. The primary objective of this study was to investigate the persistence rate of cardiac sarcoid involvement by cardiovascular magnetic resonance (CMR) imaging in patients diagnosed with cardiac sarcoidosis (CS). Moreover, we examined the additional insights into myocardial damage's characteristics gained by somatostatin receptor scintigraphy.

Methods and results: In a pilot study, we had previously identified cardiac involvement-diagnosed by CMR imaging-to be present in 29 of 188 patients (15.4%) with histologically proven, extra-CS. Out of these initial 29 CS-positive patients, 27 patients (49.9 ± 11.8 years, 59.3% male) were presently re-examined and underwent a second CMR study and complementary standard clinical testing. Somatostatin receptor scintigraphy using the ligand ⁶⁸ Ga-DOTATOC was additionally performed when clinically indicated (17 patients). Within a median follow-up period of 2.6 years, none of the initial 29 patients deceased or experienced aborted sudden cardiac death. However, two patients developed third-degree atrioventricular block that required device therapy. Among the 27 re-examined CS patients, pathological CMR findings persisted in 14 of 27 patients (51.9%). CS remission was primarily due to a resolution of acute inflammatory processes. ⁶⁸ Ga-DOTATOC positron emission tomography/computed tomography (PET/CT) identified one patient with regions of raised tracer uptake that concorded with acute inflammatory changes, as assessed by CMR; this patient received no immunosuppressive medication at the time of PET/CT execution.

Conclusions: Within follow-up, CS persisted in barely half the patients, and the patients were not afflicted with cardiac death. Additional ⁶⁸ Ga-DOTATOC PET/CT allowed for visualization of acute myocardial inflammation.

Keywords: 68Ga-DOTATOC PET/CT; Cardiac sarcoidosis; Cardiovascular magnetic resonance.

Figure 1

CMR baseline (A, B) and follow‐up examination (C, D) in axial (A), horizontal long axis (C), and short axis orientation (B, D) in an asymptomatic patient without abnormalities in standard clinical testing. CMR demonstrates mid‐myocardial and subepicardial late gadolinium enhancement within the septal wall (arrows). Data correspond to Case 14 in Table 3. CMR, cardiac magnetic resonance.

Figure 2

CMR, ⁶⁸Ga‐DOTATOC PET/CT, and ⁶⁸Ga‐DOTATOC PET/CMR fused images (from left to right) of a 48‐year‐old woman with histologically proven pulmonary sarcoidosis and previously CMR‐confirmed cardiac affection. Follow‐up CMR illustrates mid‐myocardial oedema (full‐line arrow) alongside the mid‐ventricular anteroseptal myocardium and mid‐myocardial/subepicardial late gadolinium enhancement (dotted‐line arrow) at the mid‐ventricular septal level. Radionuclide imaging visualizes the highest focal ⁶⁸Ga‐DOTATOC uptake alongside the mid‐anteroseptal myocardium (red asterisk). CMR, cardiovascular magnetic resonance; Gd, gadolinium; HLA, horizontal long axis; PET, positron emission tomography; T1w, T1 weighted; T2w, T2 weighted; VLA, vertical long axis.

Figure 3

Baseline CMR (A, C) and 6 month follow‐up (B, D) of a 59‐year‐old cardiac asymptomatic patient. This woman suffered from hepatic sarcoidosis that had been histologically proven by liver biopsy. The initial LGE image in short axis view shows a striatal mid‐myocardial enhancement within the basal inferior wall (A) with corresponding oedema in the T2 black‐blood image (C). Both LGE (B) and oedema (D) were not detectable within the follow‐up examination. Data correspond to those of Case 1 in Table 3. CMR, cardiovascular magnetic resonance; LGE, late gadolinium enhancement.