Role of serial 18F-fludeoxyglucose positron emission tomography in determining the therapeutic efficacy of immunosuppression and clinical outcome in patients with cardiac sarcoidosis.

BACKGROUND: Myocardial inflammation and perfusion defects detected by 18F-fludeoxyglucose (FDG) and Rubidium-82 positron emission tomography (PET) may be associated with ventricular arrhythmias (VAs) in cardiac sarcoidosis (CS). The role of serial quantitative PET in determining the effect of treatment on myocardial inflammation and clinical outcomes is yet to be defined. METHODS: Newly diagnosed CS patients with active myocardial inflammation (maximum standardised uptake value (SUVmax) ≥ 2.5) were treated with immunosuppression, then underwent repeat FDG-PET, Rubidium-82, and echocardiographic imaging 6-12 months later. Serial changes in SUVmax, SUVmean, inflammatory extent, perfusion defect (PD) extent, metabolism/perfusion mismatch extent, global cardiac metabolic activity, and left ventricular ejection fraction (LVEF) were assessed. The primary endpoint was a composite of all-cause mortality, serious VA and heart-failure (HF) hospitalisation. Event data were recorded from the date of the second FDG-PET. RESULTS: The study population consisted of 113 patients (66% male, age: 55 ± 11 years, LVEF: 54 ± 13%). SUVmax reduced from 4.5 (interquartile range: 3.3-7.1) to 2.7 (2.2-3.6). Overall, 94 (83%) patients saw serial reduction in SUVmax, with 42 (37%) demonstrating complete response (SUVmax <2.5). Following a median of 46 (25-57) months, 28 (25%) patients reached the endpoint (8 deaths, 17 VAs, and 3 HF hospitalisations). PD extent (Hazard ratio 1.03, 95% confidence interval: 1.01-1.05; p = 0.035) was a significant predictor of outcome following treatment, even after accounting for LVEF and change in SUVmean. The risk of adverse events was the greatest in those with a pre-treatment or post-treatment PD extent of >10%. CONCLUSION: In our cohort with active CS, following a treatment-induced reduction in myocardial inflammation, PD extent was the main predictor of adverse events.

Cardiac hydatid cyst in left ventricular free wall.

UNLABELLED: We report a rare case of a cardiac hydatid cyst that was incidentally found during routine work up for a redo-CABG and was picked up on echocardiography and confirmed by magnetic resonance imaging and, after successful removal, further confirmed by histopathology. The report emphasizes the importance of early and urgent surgery for such cardiac hydatid cysts whenever discovered to prevent fatal and unexpected death. Cardiac hydatidosis is a most infrequent type, in comparison with hydatidosis of the liver (65%) and lung (25%). LEARNING POINTS: Hydatidosis or cystic echinococcosis is caused by infection with the metacestode stage of the tapeworm Echinococcus (family Taeniidae). The adult tapeworm is usually found in dogs or other canines; the tapeworm eggs are expelled in the animal's feces and humans become infected after ingestion of the eggs. The initial phase of primary infection is asymptomatic.Cardiac hydatidosis is extremely rare, more commonly the liver and lungs are affected.Morbidity from heart echinococcosis in men is three times higher than that in women. Solitary cysts occur in almost 60% of the cases; the most frequent location is the ventricular myocardium and they are usually subepicardially located, hence they rarely rupture in the pericardial space. The left ventricle is damaged twofold to threefold more frequently than the right one.The diagnosis of echinococcosis in heart can be divided into two steps: detection of the cyst and its identification as echinococcus. It is based on serological reactions, echocardiography, X-ray, computerized tomography, and/or magnetic resonance imaging.The most dangerous complication of cardiac echinococcosis is cyst perforation. After cyst perforation three quarters of the patients die from septic shock or embolic complications.It is very important to understand that chemotherapy may lead to cyst death, and destruction of its wall and result in cyst rupture. Therefore, no germicide must be administered before surgical removal.