The excellent paper by Kusano et al1 recently published in JACC: Asia showed that, nationwide in Japan, cardiac sarcoidosis (CS) diagnosed clinically is less advanced and has better prognosis than CS diagnosed from endomyocardial biopsies. In the Discussion, the authors compare their mortality data with ours from the nationwide Finnish CS registry, ongoing since 2008.2,3 However, the death rates cited from our reports are erroneously high, as they include nonfatal events2 and cases diagnosed at autopsy.3 For a more proper comparison, we present (Table 1) outcome data for patients included in our CS registry by the end of 2015 without cases diagnosed at autopsy or transplantation (n = 284, mean age 50 ± 10 years, 74% female).3,4 Their presenting manifestations were nearly equal in type and frequency with the Japanese cohort; 95% were given corticosteroids and 73% received an implantable cardioverter-defibrillator. Compared with the data of Kusano et al, the outcomes shown in Table 1 suggest differences between the 2 nationwide cohorts that, interestingly, are directionally opposite for fatal and nonfatal events The 5-year and 10-year all-cause mortalities were 5% and 15% in Finland vs 10% and 19% in Japan, while the corresponding rates of all adverse events were 32% and 47% in Finland vs 20% and 31% in Japan, respectively. The differences may relate to the disparities between the Finnish and Japanese CS cohorts in age (mean age 50 years vs 60 years), proportion of myocardial biopsy-based diagnoses (54% vs 18%), use of corticosteroids (95% vs 84%), and in particular, rates of implantable cardioverter-defibrillator implantations (73% vs 33%). As Table 1 shows, diagnosis of CS by myocardial histology implied poorer event-free survival also in Finland.
Table 1.
Outcome of Patients With a Lifetime Diagnosis of CS in Finland
| Outcome | All Patients (n = 284) | Patients With Definite CS (n = 150)a | Patients With Probable CS (n = 134)b | P Value |
|---|---|---|---|---|
| Survivalc | 0.114 | |||
| 5-y, % | 95 (93-98) | 94 (89-98) | 97 (94-100) | |
| 10-y, % | 85 (79-91) | 83 (75-91) | 88 (78-97) | |
| Survival free of transplantation | 0.006 | |||
| 5-y, % | 94 (91-97) | 91 (86-96) | 97 (94-100) | |
| 10-y, % | 80 (73-86) | 74 (65-84) | 86 (76-96) | |
| Survival free of transplantation and appropriate ICD therapy | <0.0001 | |||
| 5-y, % | 68 (62-74) | 56 (48-65) | 81 (74-88) | |
| 10-y, % | 53 (45-61) | 41 (31-51) | 66 (55-78) |
Values are estimates of survival (95% confidence interval) from Kaplan-Meier analysis. P values refer to log-rank comparison between the diagnostic subgroups of CS.
CS = cardiac sarcoidosis; ICD = implantable cardioverter-defibrillator.
Myocardial histology of sarcoidosis.
Extracardiac sarcoidosis histology (mandatory) with clinical manifestations and cardiac imaging compatible with CS.
Mortality included 16 cardiac deaths (10 sudden, 6 due to heart failure), 8 noncardiac deaths, and 6 post-transplantation deaths during mean follow-up of 6.6 (interquartile range: 4.3-10.2) years. Cardiac survival (entire cohort) was 97% (interquartile range: 94%-98%) at 5 years and 93% (interquartile range: 87%-96%) at 10 years of follow-up.
Footnotes
The authors have reported that they have no relationships relevant to the contents of this paper to disclose.
The authors attest they are in compliance with human studies committees and animal welfare regulations of the authors’ institutions and Food and Drug Administration guidelines, including patient consent where appropriate. For more information, visit the Author Center.
References
- 1.Kusano K., Ishibashi K., Noda T., et al. Prognosis and outcomes of clinically diagnosed cardiac sarcoidosis without positive endomyocardial biopsy findings. JACC: Asia. 2021;1:385–395. doi: 10.1016/j.jacasi.2021.09.005. [DOI] [PMC free article] [PubMed] [Google Scholar]
- 2.Kandolin R., Lehtonen J., Airaksinen J., et al. Cardiac sarcoidosis: epidemiology, characteristics, and outcome over 25 years in a nationwide study. Circulation. 2015;131:624–632. doi: 10.1161/CIRCULATIONAHA.114.011522. [DOI] [PubMed] [Google Scholar]
- 3.Ekström K., Lehtonen J., Nordenswan H.-K., et al. Sudden death in cardiac sarcoidosis: an analysis of clinical and cause-of-death registries. Eur Heart J. 2019;40:3121–3128. doi: 10.1093/eurheartj/ehz428. [DOI] [PubMed] [Google Scholar]
- 4.Nordenswan H.-K., Lehtonen J., Ekström K., et al. Manifestations and outcome of cardiac sarcoidosis and idiopathic giant cell myocarditis by 25-year nationwide cohorts. J Am Heart Assoc. 2021;10 doi: 10.1161/JAHA.120.019415. [DOI] [PMC free article] [PubMed] [Google Scholar]