Absence of Pre-Transplant Pulmonary Features of Sarcoidosis is of Low Negative Predictive Value in End-Stage Cardiac Sarcoidosis

Abstract

Purpose Cardiac sarcoidosis is a potentially reversible etiology of heart failure if identified and managed in a timely fashion. Given the multisystem nature of the disease and need for a high index of suspicion, diagnosis of cardiac sarcoidosis is difficult, and the underlying cause remains speculative. Methods In a single-center retrospective case-control study of 15 patients with pathologic evidence of cardiac sarcoidosis that required cardiac transplantation or left ventricular assist device placement, diagnosed by diagnostic granulomas on native heart cardiectomy or apical core, and 33 matched controls, we collected pre-transplant pulmonary function testing (PFT) and right heart catheterization (RHC) data. We performed a blinded review of pre-transplant chest CT to categorize each scan as likely, possible, or unlikely for sarcoidosis. Results Mean age in the cardiac sarcoidosis group was 59 years and 67% were male. The FVC, FEV1, TLC, and DLCO were similar in both groups. RHC showed comparable hemodynamics with a non-significant trend towards lower cardiac index and lower mixed venous O2 saturation in the sarcoidosis group. Figure 1 shows the distribution of chest CT interpretation. Sensitivity and specificity of the chest CT classification in predicting cardiac sarcoidosis were 0.79 and 0.38, respectively, with positive predictive value of 0.41 (95%CI, 0.22-0.61) and negative predictive value of 0.77 (0.46-0.95). Conclusion PFT and RHC data did not independently differentiate the likelihood of cardiac sarcoidosis in our sample. Chest CT scans may identify patients with nonischemic heart failure who need to be considered for workup of cardiac sarcoidosis. However, absence of clear pulmonary radiographic or PFT finding at the time of tertiary referral did not exclude the diagnosis. It remains unclear whether sarcoidosis with end-stage physiology limited to the heart represents a distinct pathological entity from pulmonary-predominant sarcoidosis.