Tissue characterization of benign cardiac tumors by cardiac magnetic resonance imaging, a review of core imaging protocol and benign cardiac tumors.

Generally, cardiac masses are initially suspected on routine echocardiography. Cardiac magnetic resonance (CMR) imaging is further performed to differentiate tumors from pseudo-tumors and to characterize the cardiac masses based on their appearance on T1/T2-weighted images, detection of perfusion and demonstration of gadolinium-based contrast agent uptake on early and late gadolinium enhancement images. Further evaluation of cardiac masses by CMR is critical because unnecessary surgery can be avoided by better tissue characterization. Different cardiac tissues have different T1 and T2 relaxation times, principally owing to different internal biochemical environments surrounding the protons. In CMR, the signal intensity from a particular tissue depends on its T1 and T2 relaxation times and its proton density. CMR uses this principle to differentiate between various tissue types by weighting images based on their T1 or T2 relaxation times. Generally, tumor cells are larger, edematous, and have associated inflammatory reactions. Higher free water content of the neoplastic cells and other changes in tissue composition lead to prolonged T1/T2 relaxation times and thus an inherent contrast between tumors and normal tissue exists. Overall, these biochemical changes create an environment where different cardiac masses produce different signal intensity on their T1- weighted and T2- weighted images that help to discriminate between them. In this review article, we have provided a detailed description of the core CMR imaging protocol for evaluation of cardiac masses. We have also discussed the basic features of benign cardiac tumors as well as the role of CMR in evaluation and further tissue characterization of these tumors.

Case report: Diagnosis of hereditary hemorrhagic telangiectasia (Osler Weber Rendu Syndrome) in a 23-year-old male presented with anemia and thrombocytopenia and its response to bevacizumab.

Osler Weber Rendu Syndrome (OWS) is characterized by the development of abnormally dilated blood vessels, which manifest as arteriovenous shunts (pulmonary, gastrointestinal, hepatic, and cerebral) and mucocutaneous telangiectasias (lips, tongue, and fingertips). It is an autosomal dominant disease with a defect in transforming growth factor beta superfamily genes. This defect results in increased angiogenesis and disruption of vessel wall integrity. The disease remains underreported, with occasional history of recurrent epistaxis, iron deficiency anemia, and gastrointestinal bleeding in moderate to severe cases. Diagnosis is based on clinical presentation and confirmed by genetic testing. Various local (nasal saline, air humidification, laser ablation, and electric cauterization for epistaxis and endoscopic Argon Plasma Coagulation-APC for active GI bleeding), surgical, and systemic (tranexamic acid and antiangiogenic agents like bevacizumab and thalidomide) treatment options are used depending upon disease severity. Here, we present a case with recurrent gastrointestinal bleeding refractory to endoscopic APC ablation and thalidomide and severe symptomatic anemia requiring multiple packed red cell transfusions. The patient was ultimately started on bevacizumab, to which he had a good response and has remained in remission for 8 months as of now. This case emphasizes the need to have a low threshold of suspicion to diagnose HHT and start targeted therapy like bevacizumab early on in moderate to severe cases of HHT rather than just relying on temporizing palliative measures like ablation, cauterization, and tranexamic acid.