Pacemaker, Artificial

Humans ; Bradycardia/therapy* ; Tricuspid Valve Insufficiency ; Pacemaker, Artificial/adverse effects* ; Cardiac Pacing, Artificial

Temporary cardiac pacing is an essential technique in the diagnosis and treatment of arrhythmias. Due to its urgency, complexity, and uncertainty, it is necessary to develop an evidence-based emergency operation norms. Currently, there is no specific consensus guidelines at home or abroad. The Emergency Branch of Chinese Medical Association organized relevant experts to draft the Chinese emergency expert consensus on bedside temporary cardiac pacing (2023) to guide the operation and application of bedside cardiac pacing. The formulation of the consensus adopts the consensus meeting method and the evidentiary basis and recommendation grading of the Oxford Center for Evidence-based Medicine in the United States. A total of 13 recommendations were extracted from the discussion on the methods of bedside temporary cardiac pacing, the puncture site of transvenous temporary cardiac pacing, the selection of leads, the placement and placement of leads, pacemaker parameter settings, indications, complications and postoperative management. The recommended consensus includes the choice between transcutaneous and transvenous pacing, preferred venous access for temporary transvenous pacing, the target and best guidance method for implantation of bedside pacing electrodes, recommended default pacemaker settings, recommended indications for sinoatrial node dysfunction, atrioventricular block, acute myocardial infarction, cardiac arrest, ventricular and supraventricular arrhythmias. They also recommended ultrasound guidance and a shortened temporary pacing support time to reduce complications of temporary transvenous cardiac pacing, recommended bedrest, and anticoagulation after temporary transvenous pacing. Bedside temporary cardiac pacing is generally safe and effective. Accurate assessment, correct selection of the pacing mode, and timely performance of bedside temporary cardiac pacing can further improve the survival rate and prognosis of related emergency patients.
Humans ; Cardiac Pacing, Artificial/methods* ; Pacemaker, Artificial ; Arrhythmias, Cardiac/therapy* ; Myocardial Infarction/therapy* ; Electrodes

Objective: To determine the feasibility of using temporary permanent pacemaker (TPPM) in patients with high-degree atrioventricular block (AVB) after transcatheter aortic valve replacement (TAVR) as bridging strategy to reduce avoidable permanent pacemaker implantation. Methods: This is a prospective observational study. Consecutive patients undergoing TAVR at Beijing Anzhen Hospital and the First Affiliated Hospital of Zhengzhou University from August 2021 to February 2022 were screened. Patients with high-degree AVB and TPPM were included. Patients were followed up for 4 weeks with pacemaker interrogation at every week. The endpoint was the success rate of TPPM removal and free from permanent pacemaker at 1 month after TPPM. The criteria of removing TPPM was no indication of permanent pacing and no pacing signal in 12 lead electrocardiogram (EGG) and 24 hours dynamic EGG, meanwhile the last pacemaker interrogation indicated that ventricular pacing rate was 0. Routinely follow-up ECG was extended to 6 months after removal of TPPM. Results: Ten patients met the inclusion criteria for TPPM, aged (77.0±11.1) years, wirh 7 females. There were 7 patients with third-degree AVB, 1 patient with second-degree AVB, 2 patients with first degree AVB with PR interval>240 ms and LBBB with QRS duration>150 ms. TPPM were applied on the 10 patients for (35±7) days. Among 8 patients with high-degree AVB, 3 recovered to sinus rhythm, and 3 recovered to sinus rhythm with bundle branch block. The other 2 patients with persistent third-degree AVB received permanent pacemaker implantation. For the 2 patients with first-degree AVB and LBBB, PR interval shortened to within 200 ms. TPPM was successfully removed in 8 patients (8/10) at 1 month without permanent pacemaker implantation, of which 2 patients recovered within 24 hours after TAVR and 6 patients recovered 24 hours later after TAVR. No aggravation of conduction block or permanent pacemaker indication were observed in 8 patients during follow-up at 6 months. No procedure-related adverse events occurred in all patients. Conclusion: TPPM is reliable and safe to provide certain buffer time to distinguish whether a permanent pacemaker is necessary in patients with high-degree conduction block after TAVR.
Female ; Humans ; Atrioventricular Block/therapy* ; Feasibility Studies ; Transcatheter Aortic Valve Replacement ; Pacemaker, Artificial ; Bundle-Branch Block

Humans ; Cardiac Catheters ; Pacemaker, Artificial ; Arrhythmias, Cardiac

In order to solve the problem of communication interference and communication distance caused by the rapid pacing system when establishing the rapid atrial fibrillation model, a low-power implantable pacing system based on 433 MHz communication frequency to form a star network is designed. The system includes an implantable pacemaker, a programmer head, and programmer software. The pacemaker is composed of a wireless communication module, a pacing module, an ECG monitoring module, and a power management module. The programmer head acts as an intermediate node in the star network and is controlled by PC programmer software to program each pacemaker. This article introduces the hardware design and software flow of each part of the system, and describes the results of in vivo simulation and in vivo animal models of the system. The results show that the designed system and application method are effective and feasible for the rapid atrial pacing atrial fibrillation model. 433 MHz wireless communication, implantable, pacemaker system, low-power, ECG monitoring.
Animals ; Atrial Fibrillation/therapy* ; Electrocardiography ; Equipment Design ; Pacemaker, Artificial ; Prostheses and Implants ; Wireless Technology

The unipolar/bipolar pacing mode of pacemaker is related to its circuit impedance, which affects the battery life. In this study, the in vitro experiment scheme of pacemaker circuit impedance test was constructed. The human blood environment was simulated by NaCl solution, and the experimental environment temperature was controlled by water bath. The results of in vitro experiments showed that under the experimental conditions similar to clinical human parameters, the difference between the circuit impedance of bipolar mode and unipolar mode is 120~200 Ω. The results of the in vitro experiment confirmed that the circuit impedance of bipolar circuit was larger than that of unipolar mode, which was found in clinical practice. The results of this study have reference value to the optimization of pacing mode and the reduction of pacemaker power consumption.
Cardiac Pacing, Artificial/methods* ; Electric Impedance ; Humans ; Pacemaker, Artificial ; Prostheses and Implants

Objective: To explore the predictive value of the impedance measured during leadless pacemaker Micra implantation on the trend of changes of pacing threshold post implantation. Methods: This is a retrospective cross-sectional study. Patients who received implantation of leadless pacemaker Micra at the Second Xiangya Hospital of Central South University from December 2019 to August 2020 were enrolled. The clinical data and the intraoperative electrical parameters during leadless pacemaker implantation were collected. The impedance and pacing threshold data were analyzed at three time points: immediate release, 5-10 min after release, and after traction test. Receiver operating characteristic (ROC) curves and the area under the curve (AUC) were used to analyze the value of the impedance at immediate release on predicting the trend of changes of pacing threshold post implantation. Results: A total of 21 patients (mean age: (72.2±12.5) years, 12 males) were included. The impedance of 21 patients was (798.1±35.3) Ω immediately after implantation, (800.9±35.6) Ω after 5-10 minutes of release, and (883.6±31.7) Ω after traction test. Impedance was similar between the three time points (P>0.05). The threshold was (0.97±0.11) V/0.24 ms immediately after implantation, (0.95±0.12) V/0.24 ms at 5-10 min after the release, and (0.59±0.06) V/0.24 ms after the traction test. The threshold was significantly lower after the traction test than that immediately after release (P=0.003) and than that at 5-10 minutes after release (P=0.008), suggesting a decreased tendency of the threshold over time. According to the analysis of the ROC curve, the immediate impedance after the release ≥680 Ω could predict the ideal pacing threshold after the traction test (AUC=0.989, 95%CI 0.702-0.964, P<0.001), the prediction sensitivity was 87%, and the specificity was 100%. The pacing threshold would be not ideal with the immediate impedance ≤ 520 Ω (95%CI 0.893-1.000, P<0.001), the sensitivity was 100%, and the specificity was 80%. Conclusions: The impedance immediately after the release has predictive value for the changing trend of threshold post leadless pacemaker Micra implantation. Impedance ≥680 Ω immediately after release is often related with ideal pacing threshold after the traction test. In contrast, the impedance ≤ 520 Ω pacing is often related with unsatisfactory threshold after the traction test, therefore, it is recommended to find a new pacing site to achieve the impedance ≥680 Ω immediately after release during leadless pacemaker Micra implantation.
Aged ; Aged, 80 and over ; Cardiac Pacing, Artificial ; Cross-Sectional Studies ; Electric Impedance ; Humans ; Male ; Middle Aged ; Pacemaker, Artificial ; Retrospective Studies ; Treatment Outcome

Objective: To analyze the feasibility and safety of bridge therapy with active fixed electrodes connected to external permanent pacemakers (AFLEP) for patients with infective endocarditis after lead removal and before permanent pacemaker implantation. Methods: A total of 44 pacemaker-dependent patients, who underwent lead removal due to infective endocarditis in our center from January 2015 to January 2020, were included. According to AFLEP or temporary pacemaker option during the transition period, patients were divided into AFLEP group or temporary pacemaker group. Information including age, sex, comorbidities, indications and types of cardial implantable electionic device (CIED) implantation, lead age, duration of temporary pacemaker or AFLEP use, and perioperative complications were collected through Haitai Medical Record System. The incidence of pacemaker perception, abnormal pacing function, lead perforation, lead dislocation, lead vegetation, cardiac tamponade, pulmonary embolism, death and newly infection of implanted pacemaker were compared between the two groups. Pneumothorax, hematoma and the incidence of deep vein thrombosis were also analyzed. Results: Among the 44 patients, 24 were in the AFLEP group and 20 in the temporary pacemaker group. Age was younger in the AFLEP group than in the temporary pacemaker group (57.5(45.5, 66.0) years vs. 67.0(57.3, 71.8) years, P=0.023). Male, prevalence of hypertension, diabetes mellitus, chronic renal dysfunction and old myocardial infarction were similar between the two groups (all P>0.05). Lead duration was 11.0(8.0,13.0) years in the AFLEP group and 8.5(7.0,13.0) years in the temporary pacemaker group(P=0.292). Lead vegetation diameter was (8.2±2.4)mm in the AFLEP group and (9.1±3.0)mm in the temporary pacemaker group. Lead removal was successful in all patients. The follow-up time in the AFLEP group was 23.0(20.5, 25.5) months, and the temporary pacemaker group was 17.0(14.5, 18.5) months. In the temporary pacemaker group, there were 2 cases (10.0%) of lead dislocation, 2 cases (10.0%) of sensory dysfunction, 2 cases (10.0%) of pacing dysfunction, and 2 cases (10.0%) of death. In the AFLEP group, there were 2 cases of abnormal pacing function, which improved after adjusting the output voltage of the pacemaker, there was no lead dislocation, abnormal perception and death. Femoral vein access was used in 8 patients (40.0%) in the temporary pacemaker group, and 4 patients developed lower extremity deep venous thrombosis. There was no deep venous thrombosis in the AFLEP group. The transition treatment time was significantly longer in the AFLEP group than in the temporary pacemaker group (19.5(16.0, 25.8) days vs. 14.0(12.0, 16.8) days, P=0.001). During the follow-up period, there were no reinfections with newly implanted pacemakers in the AFLEP group, and reinfection occurred in 2 patients (10.0%) in the temporary pacemaker group. Conclusions: Bridge therapy with AFLEP for patients with infective endocarditis after lead removal and before permanent pacemaker implantation is feasible and safe. Compared with temporary pacemaker, AFLEP is safer in the implantation process and more stable with lower lead dislocation rate, less sensory and pacing dysfunction.
Humans ; Male ; Bridge Therapy ; Feasibility Studies ; Pacemaker, Artificial ; Endocarditis, Bacterial/etiology* ; Electrodes ; Device Removal

Coronary angiography (CAG) as a typical imaging modality for the diagnosis of coronary diseases hasbeen widely employed in clinical practices. For CAG-based computer-aided diagnosis systems, accurate vessel segmentation plays a fundamental role. However, patients with bradycardia usually have a pacemaker which frequently interferes the vessel segmentation. In this case, the segmentation of vessels will be hard. To mitigate interferences of pacemakers and then extract main vessels more effectively in CAG images, we propose an approach. At first, a pseudo CAG (pCAG) image is generated through a part of a CAG sequence, in which the pacemaker exists. Then, a local feature descriptor is employed to register the relative location of pacemaker between the pCAG image and the target CAG image. Finally, combining the registration result and segmentation results of main vessels and pacemaker, interferences of pacemaker are removed and the segmentation of main vessels is improved. The proposed method is evaluated based on 11 CAG images with pacemakers acquired in clinical practices. An optimization ratio of the Dice coefficient is 12.04%, which demonstrates that our method can remove overlapping pacemakers and achieve the improvement of main vessel segmentation in CAG images.Our method can further become a helpful component in a CAG-based computer-aided diagnosis system, improving its diagnosis accuracy and efficiency.
Humans ; Coronary Angiography/methods* ; Diagnosis, Computer-Assisted ; Pacemaker, Artificial ; Image Processing, Computer-Assisted/methods* ; Algorithms