A case of an elderly patient with severe aortic insufficiency who carried high risks for surgical valve replacement. After a detailed preoperative evaluation, the patient successfully received transapical transcatheter aortic valve replacement. Postoperatively, complete left bundle branch block developed, resulting in impaired left ventricular function. Despite guideline-directed medical therapy for heart failure, cardiac function showed no significant recovery. At 4.5 months post-surgery, left bundle branch pacing was performed, leading to a marked improvement in cardiac function.
Aged ; Humans ; Male ; Aortic Valve Insufficiency/surgery* ; Bundle-Branch Block/etiology* ; Cardiac Pacing, Artificial ; Postoperative Complications/therapy* ; Transcatheter Aortic Valve Replacement/adverse effects*

Objective: Explore the relationship between tip of the left bundle branch pacing lead and anatomic location of left bundle branch as well as the mechanism of left bundle branch current of injury. To clarify the clinical value of left bundle branch current of injury during operation. Methods: The pacing leads were implanted in the hearts of two living swines. Intraoperative electrophysiological study confirmed that the left bundle branch or only the deep left ventricular septum was captured at low output. Immediately after operation, the gross specimen of swine hearts was stained with iodine to observe the gross distribution of His-purkinje conduction system on the left ventricular endocardium and its relationship with the leads. Subsequently, the swine hearts were fixed with formalin solution, and the pacing leads were removed after the positions were marked. The swine hearts were then sectioned and stained with Masson and Goldner trichrome, and the relationship between the anatomic location of the conduction system and the tip of the lead was observed under a light microscope. Results: After iodine staining of the specimen, the His-purkinje conduction system was observed with the naked eye in a net-like distribution, and the lead tip was screwed deeply and fixed in the left bundle branch area of the left ventricular subendocardium in the ventricular septum. Masson and Goldner trichrome staining showed that left bundle branch pacing lead directly passed through the left bundle branch when there was left bundle branch potential with left bundle branch current of injury, while it was not directly contact the left bundle branch when there was left bundle branch potential without left bundle branch current of injury. Conclusion: The left bundle branch current of injury observed on intracardiac electrocardiogram during His-purkinje conduction system pacing suggests that the pacing lead directly contacted the conduction bundle or its branches, therefore, the captured threshold was relatively low. Left bundle branch current of injury can be used as an important anatomic and electrophysiological evidence of left bundle branch capture.
Animals ; Swine ; Bundle of His/physiology* ; Ventricular Septum ; Cardiac Pacing, Artificial ; Heart Conduction System ; Electrocardiography ; Iodine

Humans ; Heart Failure/therapy* ; Cardiac Resynchronization Therapy

Objective: Explore the relationship between tip of the left bundle branch pacing lead and anatomic location of left bundle branch as well as the mechanism of left bundle branch current of injury. To clarify the clinical value of left bundle branch current of injury during operation. Methods: The pacing leads were implanted in the hearts of two living swines. Intraoperative electrophysiological study confirmed that the left bundle branch or only the deep left ventricular septum was captured at low output. Immediately after operation, the gross specimen of swine hearts was stained with iodine to observe the gross distribution of His-purkinje conduction system on the left ventricular endocardium and its relationship with the leads. Subsequently, the swine hearts were fixed with formalin solution, and the pacing leads were removed after the positions were marked. The swine hearts were then sectioned and stained with Masson and Goldner trichrome, and the relationship between the anatomic location of the conduction system and the tip of the lead was observed under a light microscope. Results: After iodine staining of the specimen, the His-purkinje conduction system was observed with the naked eye in a net-like distribution, and the lead tip was screwed deeply and fixed in the left bundle branch area of the left ventricular subendocardium in the ventricular septum. Masson and Goldner trichrome staining showed that left bundle branch pacing lead directly passed through the left bundle branch when there was left bundle branch potential with left bundle branch current of injury, while it was not directly contact the left bundle branch when there was left bundle branch potential without left bundle branch current of injury. Conclusion: The left bundle branch current of injury observed on intracardiac electrocardiogram during His-purkinje conduction system pacing suggests that the pacing lead directly contacted the conduction bundle or its branches, therefore, the captured threshold was relatively low. Left bundle branch current of injury can be used as an important anatomic and electrophysiological evidence of left bundle branch capture.
Animals ; Swine ; Bundle of His/physiology* ; Ventricular Septum ; Cardiac Pacing, Artificial ; Heart Conduction System ; Electrocardiography ; Iodine

Humans ; Heart Failure/therapy* ; Cardiac Resynchronization Therapy

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

Humans ; Cardiac Resynchronization Therapy ; Cardiac Pacing, Artificial ; Heart Ventricles ; Heart Failure/therapy* ; Treatment Outcome ; Electrocardiography ; Ventricular Function, Left

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

INTRODUCTION: Despite the challenges related to His bundle pacing (HBP), recent data suggest an improved success rate with experience. As a non-university, non-electrophysiology specialised centre in Singapore, we report our experiences in HBP using pacing system analyser alone. METHODS: Data of 28 consecutive patients who underwent HBP from August 2018 to February 2019 was retrospectively obtained. The clinical and technical outcomes of these patients were compared between two timeframes of three months each. Patients were followed up for 12 months. RESULTS: Immediate technical success was achieved in 21 (75.0%) patients (mean age 73.3 ± 10.7 years, 47.6% female). The mean left ventricular ejection fraction was 53.9% ± 12.1%. The indications for HBP were atrioventricular block (n = 13, 61.9%), sinus node dysfunction (n = 7, 33.3%) and upgrade from implantable cardioverter-defibrillator to His-cardiac resynchronisation therapy (n = 1, 4.8%). No significant difference was observed in baseline characteristics between Timeframe 1 and Timeframe 2. Improvements pertaining to mean fluoroscopy time were achieved between the two timeframes. There was one HBP-related complication of lead displacement during Timeframe 1. All patients with successful HBP achieved non-selective His bundle (NSHB) capture, whereas only eight patients had selective His bundle (SHB) capture. NSHB and SHB capture thresholds remained stable at the 12-month follow-up. CONCLUSION Permanent HBP is feasible and safe, even without the use of an electrophysiology recording system. This was successfully achieved in 75% of patients, with no adverse clinical outcomes during the follow-up period.
Humans ; Female ; Middle Aged ; Aged ; Aged, 80 and over ; Male ; Bundle of His ; Follow-Up Studies ; Stroke Volume ; Retrospective Studies ; Treatment Outcome ; Cardiac Pacing, Artificial/adverse effects* ; Electrocardiography ; Ventricular Function, Left/physiology*

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