Objectives The number of heart failure patients has been increasing steadily and it is thought to be one of the major public health problems. Dilated cardiomyopathy (DCM) is one of the main diseases that cause heart failure. Liver function is often abnormal in heart failure as a result of the accompanying hepatomegaly caused by the right heart failure. In the patients of chronic heart failure with acute decompensation, serum bilirubin increases which indicates severe congestion and low tissue perfusion. Systolic heart failure is an important manifestation of dilated cardiomyopathy (DCM), which could cause Group 2 pulmonary hypertension (PH), also PH due to left heart failure. Some studies demonstrated that hyperbilirubinemia is associated with advanced right heart failure and markedly reduced survival in patients with pulmonary aterial hypertension (PAH). There is few academic papers about serum bilirubin in the patients of Group 2 PH. The aim of this study was to analyse the difference of serum bilirubin in DCM patients with or without PH.
Methods The patients of DCM with or without PH continuously admitted during January 2007 to December 2009 were studied which included 61 cases of DCM with PH and 51 cases of DCM without PH. PH was estimated by echocardiography which was defined by pressure gradient of tricuspid regurgitation more then 2.8 m/s and dimension of right ventricle outflow tract more then 25 mm. The clinical characteristic, heart function, echocardiography and serum total bilirubin and creatinine of the DCM patients were analysed.
Results Compared to DCM without PH, no significantly difference of the sex, age, vital signs, combined diseases and arrhythmias was found, while the heart function was significantly malignant (p < 0.01), the left ventricle end-diastolic dimension, dimension of left atrium and right ventricle outflow tract were significantly dilated[(71.0 ± 9.62) mm vs (65.5 ± 7.17)mm; (52.8 ± 8.93) vs (43.9 ± 6.34)mm; (29.1 ± 5.30) mm vs (22.1 ± 3.30)mm, respectively p < 0.01], left ventricle ejective fraction was decreased [(0.281 ± 0.096) vs (0.362 ± 0.096), p < 0.01)], the incidence of pericardial effusion was increased (29/61 vs 7/51, p < 0.01), the serum total bilirubin was significantly increased [(45.3 ± 31.8)μmol/L vs (19.5 ± 9.08)μmol/L, p < 0.01] in the patients of DCM with PH.
Conclusions For the patients of DCM with PH, the serum bilirubin level was increased which might indicate severe congestion and low tissue perfusion due to low cardiac output whereas the heart dilated much more with more malignant heart function.