Background: Currently, there is a lack of guidance on selecting the optimal method for optimizing the AV interval. Objective: To evaluate the technical characteristics of His bundle pacing and compare relation optimal ventricular conduction intervals using cardiac catheterization and echocardiogram. Method: Interventional prospective study. Result: A total of 56 patients underwent His bundle pacing (HBP) with a success rate of 78.5%. The average age was 57.8 ± 19.25, and 68.1% (30 cases) were female. Selective His pacing and non-selective respectively was successfully achieved in 22 out of 44 cases (50%) and 95.4% with pacing threshold was measured at an average of 0.82 ± 0.38 volts and 1.37 ± 0.83 volts with a pulse width of 1ms. The accuracy comparing AV optimization varied in the following order: VTImitral valve > VTIaortic valve > DFTmitral valve for AVsense optimization and VTImitral valve > DFTmitral valve > VTIaortic valve for AVpace optimization. After AV optimization, myocardial contractility increased by an additional 18.6% for AVsense and 26% for AVpace. Conclusion: His bundle pacing procedure success rate of 78.5%. AV optimization results enhancement in left ventricular contractility from 18.6 to 26%.

Background: Vertebral fractures are the most common complication of osteoporosis, but more than two-thirds are asymptomatic. Therefore, the present study was conducted with the following objectives: (1) To describe some characteristics of incident asymptomatic vertebral fractures in adults aged 50 years and older in Vietnam; (2) To evaluate some factors related to incident asymptomatic vertebral fractures in adults aged 50 years and older in Vietnam. Materials and Methods: 455 adults aged 50 years and older volunteered to participate in the study. Cohort study of the Vietnam Osteoporosis Study (VOS) project. Results and Conclusions: In 29/455 cases of incident asymptomatic vertebral fractures followed after 2 years, the most common characteristics included: wedge fracture type (73.3%), grade 2 fracture (56.7%), and the most common locations are T12 and L1 (over 50%). Factors associated with incident vertebral fractures are advanced age and smoking.