A Diagnostic and Therapeutic Approach to Arrhythmias in Cardiac Sarcoidosis

Exercise-induced torsades de pointes as an unusual presentation of cardiac sarcoidosis: A case report and review of literature

BACKGROUND

Sarcoidosis is a rare multisystem disease characterized histologically by non-caseating granuloma formation in the affected organ. While cardiac sarcoidosis is found on autopsy in up to 25% of sarcoidosis cases, it is still underdiagnosed and is associated with a poor prognosis. Although the etiology of sarcoidosis remains unclear, an antigen triggered exaggerated immune response has been hypothesized. Early detection and prompt management of cardiac sarcoidosis remains pivotal.

CASE SUMMARY

A 60-year-old female, with pulmonary sarcoidosis in remission, presented to the cardiology outpatient clinic for evaluation of weeks-long dyspnea on moderate exertion (New York Heart Association class II) that was relieved by rest. Submaximal exercise stress test showed multifocal ventricular extrasystoles, followed by a self-limiting torsades de pointes. Cardiac magnetic resonance imaging showed nondilated and normotrophic left ventricle with basoseptal and mid-septal dyskinesis. The magnetic resonance imaging-derived left ventricular ejection fraction was 45%. Delayed enhancement showed patchy transmural fibrosis of the septum and hyperenhancement of the papillary muscles, all in favor of extensive cardiac involvement of sarcoidosis. A double-chamber implantable cardiac defibrillator was implanted, and methylprednisolone (12 mg/d) and methotrexate (12.5 mg/wk) treatment was initiated. Follow-up and implantable cardiac defibrillator interrogation showed episodes of asymptomatic nonsustained ventricular tachycardia and an asymptomatic episode of nonsustained ventricular tachycardia ending by the first antitachycardia pacing run.

CONCLUSION

Along an extensive review of the literature, this unusual case report highlights the importance of early detection of cardiac involvement of sarcoidosis, in order to avoid potential complications and increase survival.

Recommendations for the use of electrophysiological study: Update 2018

The field of cardiac electrophysiology has greatly developed during the past decades. Consequently, the use of electrophysiological studies (EPSs) in clinical practice has also significantly augmented, with a progressively increasing number of certified electrophysiology centers and specialists. Since Zipes et al published the Guidelines for Clinical Intracardiac Electrophysiology and Catheter Ablation Procedures in 1995, no official document summarizing current EPS indications has been published. The current paper focuses on summarizing all relevant data of the role of EPS in patients with different types of cardiac pathologies and provides up-to-date recommendations on this topic. For this purpose, the PubMed database was screened for relevant articles in English up to December 2018 and ESC and ACC/AHA Clinical Practice Guidelines, and EHRA/HRS/APHRS position statements related to the current topic were analyzed. Current recommendations for the use of EPS in clinical practice are discussed and presented in 17 distinct cardiac pathologies. A short rationale, evidence, and indications are provided for each cardiac disease/group of diseases. In conclusion, because of its capability to establish a diagnosis in patients with a variety of cardiac pathologies, the EPS remains a useful tool in the evaluation of patients with cardiac arrhythmias and conduction disorders and is capable of establishing indications for cardiac device implantation and guide catheter ablation procedures.

Prognostic role of serial quantitative evaluation of 18F-fluorodeoxyglucose uptake by PET/CT in patients with cardiac sarcoidosis presenting with ventricular tachycardia

BACKGROUND

Positron emission tomography (PET) with ¹⁸F-fluorodeoxyglucose (FDG) has shown to be useful in diagnosis, staging and monitoring of cardiac sarcoidosis (CS) but its interpretation is not standardized.

OBJECTIVES

We sought to investigate the clinical impact of serial quantitative FDG uptake analysis in patients with CS presenting with ventricular tachycardia (VT) treated by catheter ablation (CA).

METHODS

We followed 20 patients (51 ± 9 years, 70% males) with CS and VT who underwent CA, with 92 serial FDG-PET scans (3-10 per patient). Myocardial FDG-avid lesions were quantified using three parameters: maximum standardized uptake value (SUV_max), partial-volume corrected mean standardized uptake value (SUV_mean) and partial-volume corrected volume-intensity product [lesion metabolic activity (LMA)]. The volume-intensity product of the entire heart [global cardiac metabolic activity (gCMA)] and the background cardiac metabolic activity (bCMA: difference between gCMA and LMA) were also calculated. The primary end-point was the occurrence of major adverse cardiac events (MACE), including death, heart transplant, hospitalization for heart failure and implantable cardioverter defibrillator (ICD) appropriate interventions. Evolution of echocardiographic parameters over follow-up was also assessed.

RESULTS

During a median follow-up of 35 (20-66) months, 18 MACE (1 death, 2 heart transplants, 12 ICD appropriate interventions, 3 hospitalizations) occurred in 12 (60%) patients. At univariable analysis, lack of PET improvement (defined by decrease in LMA of at least 25%) was the only variable associated with cardiac events during follow-up. In particular, non-responders had a 20-fold higher risk of MACE at follow-up (HR 18.96, 95% CI 2.26-159.27; p = 0.007). Moreover, a significant linear inverse relationship was observed between changes in LMA and changes in left ventricular ejection fraction over follow-up (β = -20.11; p = 0.003).

CONCLUSIONS

In patients with CS and VT, temporal change in FDG uptake evaluated by a quantitative approach is associated with parallel change in systolic function. Moreover, reduction in FDG uptake is strongly associated with fewer MACE at long-term follow-up.

Cardiac sarcoidosis: a diagnostic and therapeutic challenge

OBJECTIVE

Cardiac involvement in sarcoidosis can present in various ways, with atrioventricular (AV) block and ventricular arrhythmias being the most common signs. Because of initial non-specific findings, diagnosis can be a challenge. Very few data can support treatment decisions as cardiac manifestations of this systemic disorder are rare.

METHODS AND RESULTS

We reviewed current guidelines, cohort studies, and expert opinions concerning diagnosis and treatment of cardiac sarcoidosis.

CONCLUSIONS

Longitudinal follow-up studies are necessary to improve the diagnostic process and risk stratification of cardiac sarcoidosis. The optimal dose of steroids, indications for internal cardioverter-defibrillator (ICD), and technique and optimal timing of ablation are still under debate.

Palpitations as a presenting feature of multisystem sarcoidosis

Introduction: Sarcoidosis is described as a systemic condition characterized by non-caseating granulomas in multiple organs. In this report, we present an unusual manifestation of cardiac sarcoidosis and review management strategies.

Case presentation: A 29-year-old African-American man presented with weight loss, fatigue, dyspnea, palpitations, night sweats, painless left eye redness and bilateral leg pain over the course of three months. His physical exam revealed left conjunctival congestion and bilateral crackles on auscultation. Computerized tomography of the chest showed severe parenchymal disease with bilateral fibrotic bands. Bronchoscopy and transbronchial biopsy revealed noncaseating granulomas and multinucleated giant cells, confirming sarcoidosis. Non-sustained ventricular tachycardia developed. Cardiac MRI showed myocardial delayed gadolinium enhancement. He responded to methotrexate and steroid therapy. An implantable cardioverter-defibrillator was placed.

Discussion: Although cardiac sarcoidosis manifests in only 5% of sarcoidosis, autopsy reports indicate subclinical cardiac involvement in up to 30%. There are no established criteria for diagnosis of cardiac sarcoidosis.

Conclusion: Early recognition and diagnosis of cardiac sarcoidosis is challenging but vital due to unpredictability and high risk for malignant cardiac involvement. Newer diagnostic imaging modalities have further aided in earlier identification and prevention of sudden cardiac death.