Relationship between the abnormal diastolic vortex structure and impaired left ventricle filling in patients with hyperthyroidism.

Intraventricular hydrodynamics plays an important role in evaluating cardiac function. Relationship between diastolic vortex and left ventricular (LV) filling is still rarely elucidated. The aim of this study was to evaluate the evolution of vortex during diastole in hyperthyroidism (HT) and explore the alteration of hydromechanics characteristics with sensitive indexes.Forty-three patients diagnosed with HT were classified into 2 groups according to whether myocardial damage existed: simple hyperthyroid group (HT1, n = 21) and thyrotoxic cardiomyopathy (HT2, n = 22). Twenty-seven age- and gender-matched healthy volunteers were enrolled as the control group. Offline vector flow mapping (VFM model) was used to analyze the LV diastolic blood flow patterns and fluid dynamics. Hemodynamic parameters, vortex area (A), circulation (C), and intraventricular pressure gradient (ΔP), in different diastolic phases (early, mid, and late) were calculated and analyzed.HT2, with a lower E/A ratio and left ventricular ejection fraction (LVEF), had a larger left atrium diameter (LAD) compared with those of the control group and HT1 (P < .05). Compared with the control group, the vortex size and strength, intraventricular pressure gradient during early and mid-diastole were higher in HT1 and lower in HT2 (P < .05). And in late diastole, the vortex size and strength, intraventricular pressure gradient of HT2 became higher than those of the control group (P < .05). Good correlation could be found between CE and E/A (P < .05), CM and ΔPM (P < .01), CL and FT3 (P < .05).VFM is proven practical for detecting the relationship between the changes of left ventricular diastolic vortex and the abnormal left ventricular filling.

Role of (pro)rennin receptor in cardiomyocytes of heart failure rat model.

The role of (pro)rennin receptor (PRR) in cardiomyocytes of a heart failure (HF) rat model was studied. Spontaneously hypertensive rats (SHR) with HF (SHR-HF) or not were identified by two-dimensional (2-D) ultrasound. Age-matched Wistar Kyoto normotensive (WKY) rats were used as controls. PRR short hair RNA (sh-RNA) was injected into the heart of SHR-HF. Simultaneously SHR and controls received the same shRNA injection into the heart. Scramble shRNA was injected into the heart as controls. The expression of PRR mRNA and protein in cardiomyocytes was detected by using real-time PCR and Western blotting respectively. The heart function was evaluated by 2-D ultrasound, including eject fraction (EF%), fractional shortening (FS%), left ventricle thickness (LV), and inter-ventricular septal thickness (IVS). The number of apoptotic cardiomyocytes was counted by using flow cytometry. The results showed that the mRNA and protein expression levels of PRR were significantly higher in cardiomyocytes of SHR-HF group than in those of SHR group or control group. The apoptosis of myocytes in SHR-HF group was increased as compared with SHR group or control group. After knock-down of PRR with shRNA in SHR-HF group, the apoptosis of myocytes was reduced, resulting in the improved heart function. It was suggested that down-regulation of PRR might protect the heart from development of HF in SHR-HF by inhibiting the apoptosis of cardiomyocytes.