ABSTRACT
Objective To assess the changes of right atrial size and mechanical function after radiofrequency catheter ablation in patients with paroxysmal atrial fibrillation using real-time threedimensional echocardiography(RT-3DE), and to study the correlation between the changes of left atrial(LA)and right atrial(RA) volume and function. Methods Thirty-five patients with paroxysmal atrial fibrillation were undergone radiofrequency catheter ablation (RFCA) successfully. Transthoracic echocardiography (TTE),tissue Doppler imaging(TDI) and RT-3DE were performed before, 1 month and 3 months after procedure respectively. Late systolic volume and area of RA and LA,ejection fraction(EF) of RA and LA,late diastolic peak velocity of mitral valve inflow, tricuspid valve inflow and late diastolic peak velocity of mitral annulus and tricuspid annulus were recorded. Results The 3DE images of all patients were satisfied.LA max area and 3DE LA max volume were significantly reduced at 1 months and 3 months after procedure compared with basic stage [ ( 18.8 ± 6.3) cm2 vs (21.5 ± 6.2) cm2 , (38.8 ± 17.0) ml vs (46.1 ± 20.0) ml,P ＜ 0.05]. 3DE LA EF also declined markedly at 1 month after RFCA, and restored at 3 months later compared with baseline [(41.1 ± 13.7) % vs (51.7 ± 15.9) %, (41.1 ± 13.7) % vs (45.6 ± 18.3) %, P ＜0.05]. The size and mechanical function of the right atrial after procedure were no obvious changes. There were no evidently correlation between the changes of LA and RA volume and function. Conclusions RT3DE can provide a precise method to quantify the value of atrial volume and function. The LA size and volume are significantly reduced after RFCA in patients with paroxysmal atrial fibrillation, however, the RA size and function are no obvious changes.
ABSTRACT
Objective To evaluate the enhancement effect of the thrombus-targeted ultrasound contrast agent on acute thrombus in normal canine femoral vein.Methods Acute thrombi were created in both sides of the femoral vein in ten canine models.Targeted ultrasound contrast agent was given in a dose of(0.06) ml/kg in ten canines via intravenous bolus injection from forelimb of canine,the images of the acute thrombus were taken at 0,2,4,8,12,14 minutes after infusion of ultrasound contrast agent and stored in magneto optical disks.The images were assessed qualitatively by two independent observers and quantitatively using acoustic densitometry(AD) to determine the contrast enhancement effect of acute thrombus in normal canine femoral vein.Results After infusion of targeted ultrasound contrast agent,the thrombus was enhanced considerably and easy to be detected.AD analysis demonstrated that peak indencity(PI) and area under curve(AUC) increased with the changes of time,reaching the peak at 8th minutes after infusion of targeted ultrasound contrast agent,then decreased.PI and AUC increased at the 8th minute after infusion of targeted ultrasound contrast agent than before [((333.21)?(38.56))dB vs((168.18)?(28.18))dB,((884.40)?(94.62))dB vs((439.65)?(98.54))dB,respectively,P