Paroxysmal supraventricular tachycardia includes atrioventricular node reentry tachycardia, atrioventricular reentry tachycardia and atrial tachycardia.At present, the commonly used methods in clinical diagnosis include ventricular pacing in tachycardia, pre ventricular stimulation in refractory/non refractory period of his bundle, pacing in different parts of the atrium, parahisian pacing in sinus rhythm and stimulation in different parts of the ventricle.Ventricular pacing is one of the most commonly used methods in clinical diagnosis.However, it may lead to " false V-A-A-V" sequence after pacing.The ventricular pre phase stimulation of his bundle refractory period may appear false negative or lead to termination of tachycardia, which is not condutive to differential diagnosis.The results may be affected by pacing position, bypass position and refractory period when parahisian pacing and ventricular stimulation at different sites/frequencies are performed in sinus rhythm.Because of their respective advantages and limitations, it is necessary to integrate a variety of identification methods to improve the accuracy of diagnosis and the success rate of operation.

Objective:To investigate the electrocardiographic characteristics of left and right ventricles origin of premature ventricular contractions(PVCs) during V3 transition of precordial leads, right ventricular outflow tract (RVOT) anterior septum and right coronary sinus (RCC), and RVOT middle-posterior septum and left coronary sinus (LCC).Methods:From January 2017 to September 2019, 91 patients with ventricular extrasystole of outflow tract who had V3 transition in precordial lead and had successful radiofrequency ablation in RVOT anterior septum, middle posterior septum, LCC and RCC were selected for retrospective case control study.The electrocardiography measurements of PVCs were compared between the anteroseptal RVOT group and RCC group, as well as the middle-posterior septal RVOT group and the LCC group, respectively.The measurements included the R-wave amplitude in lead Ⅰ, Ⅱ, Ⅲ and aVF, R amplitude ratio in leads Ⅲ to Ⅱ, Q-wave amplitude in lead aVL and aVR, Q amplitude ratio in leads aVL to aVR, R-wave and S-wave amplitude from leads V1 to V3, the V2S/V3R index, the transition zone index, and the V2 transition ratio.Results:Thirty-six cases originated from the anteroseptal RVOT, and 11 from the LCC.Lead I R-wave amplitude in anterior septal RVOT was higher than LCC group((0.22±0.25) mV vs.(-0.17±0.33) mV; P=0.003). R-wave amplitude in lead Ⅱ was lower than that in the LCC group((1.59±0.35) mV vs.(1.76±0.27) mV; P=0.035). R-wave amplitude in lead aVF was lower compared with the LCC group((1.53±0.35) mV vs.(1.78±0.39) mV; P=0.050). The V2S/V3R index showed a significant difference between these two groups(1.99±0.66 vs.0.76±0.38; P<0.001). The V2 transition ratio also appeared a significant difference between the two groups(0.69±0.43 vs.1.05±0.35; P=0.005). PVCs arose from the middle-posterior septal RVOT in 32 cases, and from the RCC in 12 cases.Compared with RCC group, lead Ⅰ R-wave amplitude showed lower ((0.25±0.31) mV vs.(0.57±0.12) mV; P<0.001); R amplitude ratio in leads Ⅲ to Ⅱ higher (0.89±0.14 vs.0.72±0.18; P=0.002); Q amplitude in lead aVL((0.72±0.24) mV vs.(0.51±0.16) mV; P=0.002)higher, and Q amplitude ratio in leads aVL to aVR higher in the middle-posterior septal RVOT(0.76±0.23 vs.0.50±0.21; P=0.002). Conclusion:Among the cases with lead V3 transition, PVCs originated from the anteroseptal RVOT show significantly different R wave in lead Ⅰ, Ⅱ, aVF, V2S/V3R index, and the V2 transition ratio compared with those from the LCC.The PVCs from the middle-posterior septal RVOT and the RCC have different R wave in lead Ⅰ, R amplitude ratio in leads Ⅱ and Ⅲ, Q amplitude ratio in leads aVL and aVR.Combined with its different characteristics, it can help to identify the origin of left and right ventricles.

Objective To observe whether catheter ablation for ventricular premature complexes (PVC) has an effect on ventricular diastolic function in elderly patients.Methods Elderly patients older than 65 years of age who underwent catheter ablation from March 2012 to May 2015 for idiopathic ventricular premature complexes were enrolled.Preoperative echocardiography was performed using E／e′ for left ventricular diastolic function and venous brain natriuretic peptide (BNP) levels were measured.All patients underwent catheter ablation under the guidance of a three?dimensional mapping system.Cardiac ultrasound and BNP levels were repeated 6 months after ablation, and 24?hour electrocardiogram was performed to confirm ventricular premature complexes.Results There were a total of 89 patients with idiopathic ventricular premature complexes ( PVC) who underwent catheter ablation.81 cases were successed at 6 months,with a success rate of 91.0%.At 6 months after ablation,the E／e′ values were significantly lower ((15.3±5.2) vs ( 10.2± 3.2),( P＜0.001)) and BNP levels were significantly lower (( 202.0 ± 23.2) pg／L vs (94±13.3) pg／L),(P＜0.001).For the unsuccessful subgroup,there was no significant change in E／e′values (16.3±6.3 vs 15.2±5.6) and BNP levels ((223.0±26.8) pg／L vs (245.0±23.9) pg／L), (P＞0.05).Conclusion The number of premature ventricular beats is associated with left ventricular diastolic function,and ventricular premature catheter ablation can improve left ventricular diastolic function in elderly PVC patients.

OBJECTIVE: The design and development of split memory alloy sternum bone plate are discussed, and the effect of split memory alloy sternum bone plate internal fixation in the treatment of sternal fractures are analysed. METHODS: The structure of the product is designed according to the anatomy and physiological characteristics of human bones, and the cross section shape of the product is designed according to the cross section shape of human bones. Internal fixation is effective in the treatment of sternal fracture. RESULTS: The split memory alloy sternal plate was successfully designed and developed, and all the patients with sternal fractures treated by internal fixation were clinically healed, the hospitalization and fracture healing time were significantly shortened, and no obvious complications occurred. CONCLUSIONS The application of split memory alloy sternal plate internal fixation in the treatment of sternal fracture has the advantages of small trauma, simple operation, safety, reliable fixation, good histocompatibility and less complications, and is conducive to promoting fracture healing and respiratory function improvement.
Alloys ; Bone Plates ; Fracture Fixation, Internal ; Fracture Healing ; Humans ; Sternum/surgery*

AIM: To investigate the effect of an effective component total sterone (TSR) of Echinops latifolius Tausch, the main component of a Chinese patent medicine Cuiru Keli (national drug standard WS3-413 (Z-085)-2003 (Z), on lactation and its possible mechanism. METHODS: After mating between male and female SD rats, 60 female rats were randomly divided into normal control group, model group, TSR low-dose and high-dose groups and prolactin granule positive control group, with 12 female rats in each group and 8 newborn rats in each nest. In addition to the normal control group, the rats in each group were intraperitoneally injected with levodopa 2 mg/kg once a day for 7 days from the second day of delivery. The rats in the normal control group were given normal saline by gavage once a day for 14 days. From the beginning of self-sufficiency, the single lactation of the female rats was measured every day until the 14th day, and then the female rats in each group were killed. Pathological HE staining was used to observe the morphological changes of mammary gland tissue in each group. ELISA was used to detect the levels of serum prolactin (PRL) and 5-hydroxytryptamine (5-HT). Immunohistochemistry was used to detect the distribution of PRL in mammary gland tissue of each group. Furthermore, Real-time qPCR was used to detect the expression of milk protein, milk fat related genes β-casein, FAS, ACC and the expression of canonical Wnt signaling pathway related genes β-catenin, c-Myc, CCND1, SFRP4, DNMT1, MeCP2 in mammary gland of each group. RESULTS: Both low and high dose TSR could significantly increase the single lactation volume, improve the pathological morphology of mammary gland, and increase the serum levels of PRL and 5-HT. TSR increased the distribution of PRL and up-regulated the expression of milk protein, milk fat related genes β-casein, FAS, ACC and canonical Wnt signaling pathway related genes β-catenin, c-Myc, CCND1, SFRP4, DNMT1, MeCP2.CONCLUSION: TSR can significantly promote lactation in lactation deficient rats, and its mechanism may be related to promoting the release of PRL and 5-HT in serum, increasing the distribution of PRL in mammary gland, up-regulating the milk protein and milk fat related genes and activating the canonical Wnt signal.