ObjectiveTo explore the effectiveness and safety of the improved approach of intraoperative temporary epicardial pacing lead implantation in complete video-assisted cardiac surgery. Method We included 50 cardiac patients with video-assisted cardiac surgery indications in our hospital from September 2013 to November 2013. According to approach to placing intraoperative temporary epicardial pacing lead, the patients were divided into two groups including an improved group (30 patients with 17 males and 13 females at age of 45.6±15.7 years) and a traditional group (20 patients with 12 males and 8 females at age of 44.2±17.7 years). Time of temporary epicardial pacing lead implantation, potential perioperative complications, and clinical data of intraoperation and postoperation were compared between the two groups. Result All the patients survived during perioperative period. No intraoperative bleeding, no pericardial tamponade, no infection caused by pacing wires, as well as no relevant postoperative complications occurred. Implantation time in the improved group is shorter than that in the traditional group (P<0.001). No patient had been found situations like moderate pericardial effusion, as well as pacing leads shifting during the following-up period. ConclusionThe improved approach has shorten the implantation time, which is simpler and more effective. No patient suffers from postoperative complications during short-term following-up. But the effect in long-term following-up period is still contentious.
ObjectiveTo evaluate the efficacy of the epicardial circumferential left atrial ablation (CLAA) with pulmonary vein isolation (PVI) in curing atrial fibrillation (AF). MethodsThirty experimental pigs, weight from 60-78 kg, were divided into 3 groups with the method of random sampling:a group of AF (AF group, n=10), a group of PVI (PVI group, n=10), and a group of CLAA and PVI (CLAA+PVI group, n=10). AF mode was induced by rapid atrial pacing. After AF was induced, no ablation was performed for pigs in the AF group, PVI was performed for pigs in the PVI group with bipolar radiofrequency ablation clamp, and the CLAA+PVI group underwent CLAA after accepted PVI with bipolar radiofrequency ablation clamp. After ablation, we applied electrovert on AF pigs to recover to sinus rhythm, then we tested the vulnerability and lasting time of AF in all 3 groups. ResultsAll pigs developed a stable and sustained AF by rapid left atrial pacing. The pigs of the PVI group and the CLAA+PVI group successfully underwent ablation with the beating heart. Isolated PVI terminated AF in 3 of 20 pigs, and CLAA with PVI terminated AF in 5 of 8 pigs (15% vs. 62.5%, P=0.022). After all pigs recovered to the sinus rhythm, compared with the AF group (10/10), the incidence of sustained AF by burst pacing was statistically decreased in the PVI group (3/10, P=0.003) and the CLAA+PVI group (0/10, P<0.001). There was no statistical difference between the PVI group and the CLAA+PVI group (P=0.211). There was a statistical decreasing of AF duration in the PVI group (P=0.003) and the CLAA+PVI group (P<0.001) compared with the AF group and there was a statistical decreasing of AF duration in the CLAA+PVI group compared to that of the PVI group (P=0.008). ConclusionCompared with isolated PVI, CLAA+PVI may effectually stop the lasting of AF, restrain the recurrance of AF, and improve the treatment effect of AF.
To investigate the biomechanical effects of direct ventricular assistance and explore the optimal loading mode, this study established a left ventricular model of heart failure patients based on the finite element method. It proposed a loading mode that maintains peak pressure compression, and compared it with the traditional sinusoidal loading mode from both hemodynamic and biomechanical perspectives. The results showed that both modes significantly improved hemodynamic parameters, with ejection fraction increased from a baseline of 29.33% to 37.32% and 37.77%, respectively, while peak pressure, stroke volume, and stroke work parameters also increased. Additionally, both modes showed improvements in stress concentration and excessive fiber strain. Moreover, considering the phase error of the assist device's working cycle, the proposed assist mode in this study was less affected. Therefore, this research may provide theoretical support for the design and optimization of direct ventricular assist devices.