Risk of Adverse Outcomes Associated With Cardiac Sarcoidosis Diagnostic Schemes

Prediction of ventricular arrhythmic outcomes in suspected cardiac sarcoidosis: a comparison of cardiovascular magnetic resonance phenotyping vs. societal recommendations for implantable cardioverter-defibrillator placement

BACKGROUND AND AIMS

Implementing societal recommendations for primary prevention implantable cardioverter-defibrillators (ICDs) in cardiac sarcoidosis requires an accurate diagnosis. However, cardiac sarcoidosis diagnostic schemes are inconsistent and often produce conflicting results. This study aimed to compare the discriminative accuracy of cardiovascular magnetic resonance imaging (CMR) phenotyping with the societal recommendations for predicting long-term ventricular arrhythmic outcomes in patients with suspected cardiac sarcoidosis, regardless of their diagnostic status.

METHODS

This multicentre study included patients with histology-supported sarcoidosis who underwent CMR for suspected cardiac involvement and were ineligible for secondary prevention ICDs. The study outcome was a composite of fatal or life-threatening ventricular arrhythmias. Outcomes were compared based on eligibility for ICDs by societal recommendations and CMR phenotyping.

RESULTS

Among 1514 patients, 84 experienced the study outcome during a median follow-up of 4.5 years and a maximum follow-up of 10 years. The high-risk CMR phenotype was associated with higher 5- and 10-year incidences of the outcome (24.0% and 35.0%, respectively) compared with those who met societal recommendations. Patients with low-risk phenotypes had lower incidences (0.7% and 2.6%). Cardiovascular magnetic resonance imaging phenotyping outperformed societal recommendations in discriminative accuracy, with areas under the curve of 0.861 and 0.776 for 5- and 10-year outcomes, respectively. Additionally, CMR phenotyping had the highest adjusted subdistribution hazard ratio (19.8) for the study outcome.

CONCLUSIONS

In patients with suspected cardiac sarcoidosis, CMR phenotyping showed greater discriminative accuracy than societal recommendations for predicting fatal or life-threatening ventricular arrhythmias, suggesting that it may be more effective at identifying candidates for primary prevention ICDs.

30-Year Trends in the Incidence, Characteristics, and Outcome of Cardiac Sarcoidosis in a Nationwide Cohort

Background

Cardiac sarcoidosis (CS) is a rare but potentially fatal inflammatory cardiomyopathy.

Objectives

The authors studied temporal changes in the incidence, characteristics, and outcome of CS.

Methods

A retrospective analysis was made of a 30-year nationwide cohort of CS.

Results

The cohort comprised 511 patients with a median age of 52 years and female preponderance (69%). Altogether 77, 166, and 268 cases of CS were diagnosed in years 1988 to 2009, 2010 to 2014, and 2015 to 2019, respectively; the 5-year count of 2015 to 2019 was 134-fold the count of 1990 to 1994 (268/2) and 18-fold the count of 2000 to 2004 (268/15). Prior to 2010, compared with the later periods, CS presented more often with ventricular tachycardia/fibrillation (prevalence 36% vs 19% in 2010-2014 and 11% in 2015-2019, P < 0.001), left ventricular ejection fraction <50% (49%, 35%, and 31%; P = 0.010), and elevation of natriuretic peptides (87%, 57%, and 49%; P < 0.001). On magnetic resonance imaging, late gadolinium enhancement involved a median of 15% (IQR: 11%-22%) of left ventricular mass in studies of 1988 to 2009 (n = 16), 15% (IQR: 9%-22%) in studies of 2010 to 2014 (n = 87), and 11% (IQR: 5%-19%) in studies of 2015 to 2019 (n = 150) (P = 0.031). The respective 5-year incidences of the composite of death, heart transplantation, left ventricular-assisted device implantation, or ventricular tachyarrhythmia were 40% (95% CI: 29%-51%), 32% (95% CI: 25%-39%), and 23% (95% CI: 16%-30%) (P = 0.002). The prognostic trend disappeared after adjustment for differences in the presenting phenotype.

Conclusions

Diagnoses of incident CS have increased exponentially in Finland. Concurrently, the phenotype has turned milder and prognosis better, suggesting detection of CS at an earlier stage of its course.