Cardiac involvement in Caucasian patients with pulmonary sarcoidosis

Abstract

BackgroundCardiac sarcoidosis (CS) is a potentially life-threatening condition. At present, there is no consensus with regard to the optimal non-invasive clinical evaluation and diagnostic procedures of cardiac involvement in patients with sarcoidosis. The aim of this study in a large homogenous Scandinavian sarcoidosis cohort was therefore to identify risk factors of cardiac involvement in patients with sarcoidosis, and the value of initial routine investigation with ECG and cardiac related symptoms in screening for CS.MethodsIn this retrospective study a cohort of 1017 Caucasian patients with sarcoidosis were included. They were all screened with ECG at disease onset and investigated for CS according to clinical routine.ResultsAn abnormal ECG was recorded in 166 (16.3%) of the 1017 patients and CS was later diagnosed in 22 (13.2%) of them, compared to in one (0.1%) of the 851 sarcoidosis patients with a normal ECG (p < 0.0001). The risk for CS was higher in patients with a pathologic ECG combined with cardiac related symptoms (11/40) (27.5%) compared to those with pathologic ECG changes without symptoms (11/126) (8.7%) (p < 0.01). Furthermore, patients with Löfgren’s syndrome had a reduced risk for CS compared to those without (p < 0.05) the syndrome.ConclusionsThis study on an unusually large and homogenous sarcoidosis population demonstrate the importance of an abnormal ECG and cardiac related symptoms at disease onset as powerful predictors of a later diagnosis of cardiac sarcoidosis. In contrast, CS is very rare in subjects without symptoms and with a normal ECG. This knowledge is of importance, and may be used in a clinical algorithm, in identifying patients that should be followed and investigated extensively for the presence of CS.

Cardiac sarcoidosis: diagnosis and management

“…Familial clustering19 20 and racial phenotypes18 21 22 indicate a strong genetic element in sarcoidosis 23. Class II human leucocyte antigen (HLA) links with individual phenotypes further support a genetic association 24.…”

“…In the USA, cardiac involvement accounts for 13%–25% of sarcoidosis-related deaths 5 16. Racial groups with a high prevalence for heart involvement tend to show clear female predominance,6 17 although equal gender distribution11 or a male predominance has been described 18…”

“…ECGs are non-specific as a stand-alone investigation,49 but an abnormality (bundle branch block, ventricular ectopy, second-degree and third-degree AV block) and cardiac symptoms (ie, palpitations, syncope) appear predictive of a later diagnosis of cardiac sarcoidosis 18. Less commonly, ECG features may include a pseudoinfarction pattern, prolonged QT interval, sinus node dysfunction and prominent U waves 50 51.…”

“…Whether all patients with cardiac involvement should receive a prophylactic ICD remains contentious 1 18 52 125. Some centres will only offer ICDs when the left ventricular ejection fraction is ≤35% 30.…”

Electrocardiographic abnormalities in patients with pulmonary sarcoidosis (RCD code: III)

“…Moreover, coexistence of pathologic ECG and cardiac symptoms increased the risk of CS to 27.5%, compared to patients with abnormal ECG changes but no cardiac related symptoms 8.7% [10]. Similarly, Martusewicz-Boros and others proved that changes detected in 12-lead ECG were important risk factor for developing CS [11].…”