Discrepancy between inducibility of ventricular tachycardia and activity of cardiac sarcoidosis. Requirement of defibrillator implantation for the inactive stage of cardiac sarcoidosis

Heart Failure, Atrioventricular Block, and Ventricular Tachycardia in Sarcoidosis

Background Sarcoidosis is a granulomatous disease usually affecting the lungs, although cardiac morbidity may be common. The risk of these outcomes and the characteristics that predict them remain largely unknown. This study investigates the epidemiology of heart failure, atrioventricular block, and ventricular tachycardia among patients with and without sarcoidosis. Methods and Results We identified California residents aged ≥21 years using the Office of Statewide Health Planning and Development ambulatory surgery, emergency, or inpatient databases from 2005 to 2015. The risk of sarcoidosis on incident heart failure, atrioventricular block, and ventricular tachycardia were each determined. Linkage to the Social Security Death Index was used to ascertain overall mortality. Among 22 527 964 California residents, 19 762 patients with sarcoidosis (0.09%) were identified. Sarcoidosis was the strongest predictor of heart failure (hazard ratio [HR], 11.2; 95% CI, 10.7-11.7), atrioventricular block (HR, 117.7; 95% CI, 103.3-134.0), and ventricular tachycardia (HR, 26.1; 95% CI, 24.2-28.1) identified among all risk factors. The presence of any cardiac involvement best predicted each outcome. Approximately 22% (95% CI, 18%-26%) of the relationship between sarcoidosis and increased mortality was explained by the presence of at least 1 of these cardiovascular outcomes. Conclusions The magnitude of risk associated with sarcoidosis as a predictor of heart failure, atrioventricular block, and ventricular tachycardia, exceeds all established risk factors. Surveillance for and anticipation of these outcomes among patients with sarcoidosis is indicated, and consideration of a sarcoidosis diagnosis may be prudent among patients with heart failure, atrioventricular block, or ventricular tachycardia.

Risk assessment of patients with clinical manifestations of cardiac sarcoidosis with positron emission tomography and magnetic resonance imaging

BACKGROUND

Prior studies have shown that late gadolinium enhancement (LGE) on cardiac magnetic resonance (CMR) and fluorodeoxyglucose (FDG) positron emission tomography (PET) confer incremental risk assessment in patients with cardiac sarcoidosis (CS). However, the incremental prognostic value of the combined use of LGE and FDG compared to either test alone has not been investigated, and this is the aim of the present study.

METHODS

Retrospective observational study of 56 symptomatic patients with high clinical suspicion for CS who underwent LGE-CMR and FDG-PET and were followed for the occurrence of death and/or malignant ventricular arrhythmias (VA).

RESULTS

The combination of PET and CMR yielded the following groups: 1) LGE-negative/normal-PET (n=20), 2) LGE-positive/abnormal-FDG (n=20), and 3) LGE-positive/normal FDG (n=16). After a median follow-up of 2.6years (IQR 1.2-4.1), 16 patients had events (7 deaths, 10 VA). All, but 1, events occurred in patients with LGE. LGE-positive/abnormal-FDG (7 events, HR 10.1 [95% CI 1.2-84]; P=0.03) and LGE-positive/normal-FDG (8 events, HR 13.3 [1.7-107]; P=0.015) patients had comparable risk of events compared to the reference LGE-negative/normal-PET group. In adjusted Cox-regression analysis, presence of LGE (HR 18.1 [1.8-178]; P=0.013) was the only independent predictor of events.

CONCLUSION

CS patients with LGE alone or in association with FDG were at similar risk of future events, which suggests that outcomes may be driven by the presence of LGE (myocardial fibrosis) and not FDG (inflammation).

Management of Arrhythmias in Cardiac Sarcoidosis

The prevalence of cardiac involvement in sarcoidosis is under-recognized and is associated with multiple complications, including conduction block, arrhythmias, and sudden death. The comparative roles of common therapies have been inadequately studied. The purpose of this review is to examine the literature regarding treatments utilized to manage arrhythmias associated with cardiac sarcoidosis.

Pleomorphism during Ventricular Tachycardia: A Distinguishing Feature between Cardiac Sarcoidosis and Idiopathic VT

BACKGROUND

Ventricular tachycardia (VT), a common manifestation of cardiac sarcoidosis (CS), is associated with high morbidity and mortality. It could be mistaken for idiopathic VT (IVT) in the absence of systemic manifestations and overt cardiac structural abnormality. We studied the electrocardiogram (ECG) characteristics of VT in CS that may distinguish from IVT and also explored the relationship of the ECG characteristics with imaging findings in patients with CS.

METHODS AND RESULTS

Twelve-lead ECG characteristics of VT in CS patients (Group I = 37) were compared with IVT (Group II = 49). QRS duration, axis, morphology, VT cycle length, and cycle length variation (CLV) were analyzed. In Group I, 18 (49%) had pleomorphic VT (PLVT) and none in Group II. CLV was seen only in Group I (24%). Mean QRS duration (milliseconds) and cycle length (milliseconds) were greater in Group I (QRSd 152.49 [39.3] vs 140.9 [19.2]) and (332.2 [136.5] vs 312.9 [56.2]), the differences not statistically significant. In Group I, myocardial scar was present in 22 of 25 patients and myocardial inflammation in 28 of 29 patients as assessed by cardiac magnetic resonance imaging (delayed enhancement) and 18-fluorodeoxyglucose positron emission computed tomography, respectively. PLVT was seen more commonly in patients with involvement of >1 myocardial region than focal involvement (58% and 30%, respectively, with myocardial scar and 50% and 40%, respectively, with myocardial inflammation).

CONCLUSION

Pleomorphism and CLV during VT may be distinguishing features between IVT and VTs of CS origin.

Relationship between arrhythmogenesis and disease activity in cardiac sarcoidosis

BACKGROUND

In patients with cardiac sarcoidosis, ventricular arrhythmias and/or conduction disturbances are frequently observed and sometimes fatal. However, few reports on disease activity and arrhythmic events in cardiac sarcoidosis are available.

OBJECTIVE

The purpose of this study was to investigate the relationship between disease activity and arrhythmic events in cardiac sarcoidosis and the effect of corticosteroid therapy.

METHODS

The study population consisted of 15 cardiac sarcoidosis patients with new-onset symptomatic arrhythmia, including eight patients admitted once for complete atrioventricular block (CAVB), five patients admitted once for sustained ventricular tachycardia (VT), and two patients admitted twice for two arrhythmic events (one for CAVB and the other for sustained VT). Disease activity was evaluated by gallium-67 citrate (Ga) scintigraphy. All patients with positive Ga uptake were treated with corticosteroids, and arrhythmic events were evaluated by repeat Holter recordings.

RESULTS

Positive uptake of Ga was observed in 8 (80%) of the 10 CAVB events and in 1 (14%) of the 7 sustained VT events (80% vs 14%, P = .02). Corticosteroids abolished myocardial Ga uptake in all nine patients with positive Ga uptake. After corticosteroid therapy was started, AV conduction improved in 5 of 9 CAVB patients (including 8 patients with new-onset CAVB and one patient with history of CAVB). However, ventricular arrhythmias were not improved after corticosteroid therapy.

CONCLUSION

In cardiac sarcoidosis patients, CAVB develops mainly during the active phase of the disease. Early treatment with corticosteroids might improve AV conduction disturbance. However, sustained VT is not closely linked with disease activity and frequently develops in the advanced stage of disease.

The management of sarcoidosis by the primary care physician

Sarcoidosis is an idiopathic granulomatous disease that may affect any organ. The varied manifestations of the disease may prompt patients with sarcoidosis to seek care from primary care physicians and subspecialists. This article outlines the approach to the evaluation and treatment of sarcoidosis by primary care physicians.

Sarcoid heart disease: clinical course and treatment

Sarcoidosis is a rare granulomatous disease of unknown etiology that can affect any organ. Cardiac involvement, although uncommon, has a wide spectrum of clinical manifestations and is potentially fatal. Although there is no agreement upon a strategy for the diagnosis (which is difficult to make based on clinical information alone), the introduction of newer technology is promising and may be useful both for the early diagnosis of cardiac involvement and for the evaluation of response to therapy. Early treatment is crucial in improving symptoms and prognosis. ICD implantation and cardiac transplantation may offer improvements in management, as steroid therapy and pacemaker implantation has led to improved outcomes over the past three decades.

Ventricular tachyarrhythmia associated with cardiac sarcoidosis: its mechanisms and outcome

BACKGROUND

Cardiac sarcoidosis is increasingly recognized and is associated with poor prognosis. Ventricular tachycardia (VT) associated with cardiac sarcoidosis is the most likely cause of sudden death in most patients, but the mechanism has not been well established.

HYPOTHESIS

This study investigated the mechanisms and outcome of VT associated with cardiac sarcoidosis.

METHODS

The study included eight consecutive patients (five men, three women, aged 54 +/- 19 years) who had sustained monomorphic VT associated with cardiac sarcoidosis in our hospital.

RESULTS

The average ejection fraction was 43 +/- 11%. Twenty-two VTs were observed in these patients, and mean heart rate during VT was 192 +/- 29 beats/min (range 144-259). The phenomenon of transient entrainment was documented in 10 of 22 (45%) VTs by ventricular pacing (eight in the active phase). Another five (23%) VTs could not be entrained, but could be initiated by programmed stimulation and terminated by rapid pacing, reproducibly. In 3 of the 22 (14%) VTs, cardioversion was required urgently because of the fast rate, while the remaining 4 (18%) could be induced during electrophysiologic study.

CONCLUSIONS

In this study, there was a high possibility that the mechanism of 15 (68%) VTs was reentry. Reentrant substrate is formed not only in association with the healing of cardiac granulomas in the inactive phase of cardiac sarcoidosis but also in the active phase. Ventricular tachycardia with cardiac sarcoidosis, even if this mechanism is reentry, has different inducibility between the active and inactive phases in an electrophysiologic study. This makes the therapy for cardiac sarcoidosis (e.g., corticosteroids, antiarrhythmic agents, and catheter ablation) difficult. The implantable cardioverter-defibrillator is an effective treatment for ventricular tachyarrythmia with cardiac sarcoidosis.

Therapeutic options for sarcoidosis: new and old

The treatment of patients with sarcoidosis remains an important part of management. The role of corticosteroids has been questioned by some, while others have reported its value even in asymptomatic patients with interstitial lung disease. Cytotoxic agents have become standard therapy for some forms of chronic disease. Newer agents that modulate the immune response have been studied. A key cytokine in chronic sarcoidosis appears to be tumor necrosis factor. Drugs that inhibit its release or block its effect have been reported as effective for sarcoidosis.