Cardiac sarcoidosis presenting as sustained ventricular tachycardia

Introduction: Sarcoidosis has many possible clinical presentations since it can affect any organ, most commonly the lungs. The hallmark of the disease consists of the formation of non-necrotising granulomas. Pathogenesis is thought to rely on the interplay of genetic, environmental and epigenetic factors. This case highlights the importance of a thorough clinical history and physical examination, and the correlation with imaging findings in the diagnostic work-up of the non-ischaemic cardiomyopathy. Case description: A 57-year-old woman was admitted due to the sudden onset of malaise, dizziness, and chest discomfort. Sustained monomorphic ventricular tachycardia was evidenced and the patient rapidly evolved with haemodynamic instability; she underwent successful electrical cardioversion. The electrocardiogram afterwards showed a high-risk electrocardiographic pattern. Invasive coronary angiography excluded obstructive epicardial coronary lesions. Physical examination revealed skin lesions on the lower limbs which raised suspicion for erythema nodosum and therefore a biopsy was performed. Transthoracic echocardiography and cardiac magnetic resonance imaging revealed features consistent with an inflammatory cardiomyopathy, and an implantable cardioverter-defibrillator was placed. The histologic examination of the cutaneous lesions showed a non-necrotising granulomatous inflammatory process. Radionuclide imaging was inconclusive. The patient underwent an endomyocardial biopsy, which confirmed the diagnosis of systemic sarcoidosis with cardiac involvement. Conclusions: Systemic sarcoidosis with cardiac involvement is a challenging diagnosis. The role of imaging techniques such as transthoracic echocardiography, cardiac magnetic resonance imaging and radionuclide imaging is essential in raising suspicion and diagnosing this pathology. Endomyocardial biopsy is the ‘gold standard’ for its diagnosis; however, it has a low diagnostic yield.