The surface electrocardiogram (ECG) can provide many clues to a patient’s underlying medical condition or tendency for arrhythmogenesis. An 80-year-old man with severe aortic stenosis and an implantable cardioverter-defibrillator (ICD) for advanced heart block presented with burping, chest discomfort and intermittent pounding sensations. His ECG showed atrial fibrillation with intermittent ventricular pacing at 60 bpm characterized by irregularly irregular rhythm, absent P waves, narrow intrinsic QRS complexes alternating with wide-paced beats (left bundle branch block [LBBB] morphology, superior axis) and visible pacing spikes. Device interrogation revealed ventricular tachycardia (VT) storm with multiple appropriate ICD shocks explaining his pounding sensations. This report highlights two key teaching points: recognizing atrial fibrillation during ventricular pacing—a frequently missed diagnosis affecting nearly half of patients with pacemakers—and managing VT storm to reduce shock burden. After device reprogramming and antiarrhythmic adjustment, the patient became asymptomatic.

Human ; Male ; Aged: 65-79 Yrs Old ; Thorax ; Teaching ; Tachycardia, Ventricular ; Electrocardiography ; Atrial Fibrillation ; Bundle-branch Block ; Constriction, Pathologic

Introduction: Thyrotoxicosis typically manifests as a hypermetabolic state characterized by tachyarrhythmias, such as sinus tachycardia or atrial fibrillation. Bradyarrhythmia, specifically atrioventricular block (AVB), is a rare and atypical cardiac manifestation. While Graves’ disease is the leading cause of hyperthyroidism, non-autoimmune etiologies must be considered when thyroid-stimulating antibodies are absent. The exact mechanism for AVB in thyrotoxicosis remains unclear but may involve myocardial inflammation of the conduction system or autonomic dysfunction. Case: A 16-year-old male with no previous medical history presented with a sudden syncopal attack. Clinical evaluation revealed a complete heart block (CHB) in association with biochemical evidence of thyrotoxicosis, requiring a temporary transcutaneous pacemaker insertion. There were no features of Graves’ disease, such as exophthalmos and thyroid acropachy, and further investigation showed a negative thyroid receptor antibody (TRAb) titer with no family history of thyroid disorders. Thyroid ultrasonography showed increased vascularity, while scintigraphy imaging showed diffuse, homogeneous, and increased uptake in both thyroid lobes. The combination of negative serology and the absence of a family history, along with a hyperfunctional state on imaging, likely suggests a rare presentation of sporadic, non-autoimmune, nonfamilial form of thyrotoxicosis. Following the initiation of anti-thyroid therapy, the CHB completely resolved without the need for further cardiological intervention. He achieved a complete clinical remission after a few months and is being planned for radioactive iodine therapy. Conclusion Most of the thyrotoxicosis-associated CHB reported in the literature was due to Graves’ disease or some forms of autoimmune thyrotoxicosis, with auto-antibodies and activated lymphocytes having a role in the pathogenesis of the CHB. CHB in association with a non-autoimmune, non-familial form of thyrotoxicosis is indeed rare, and as this case illustrates, it completely went into spontaneous sinus rhythm upon initiation of conventional anti-thyroid therapy. This rare presentation of CHB is believed to have a benign clinical course.
Thyrotoxicosis ; Heart Block

OBJECTIVE: To observe the clinical efficacy of wrist-ankle acupuncture in the treatment of functional frequent premature ventricular contractions (PVCs). METHODS: A total of 64 patients with functional frequent PVCs were randomly divided into an observation group and a control group, 32 cases in each group. The observation group was treated with wrist-ankle acupuncture at bilateral upper 1 and upper 2 on the wrist. The control group received sham acupuncture at the same points as the observation group. Both groups were treated once every day from Monday to Friday, with the needles retained for 60 min each time, for a total of 4 weeks. The TCM syndrome score, the 24-hour PVC count, and MOS 36-item short form health survey (SF-36) score were compared between the two groups before and after treatment, and the clinical efficacy was evaluated after treatment. RESULTS: After treatment, the TCM syndrome scores and the 24-hour PVC counts in both groups were reduced compared with those before treatment (P<0.01), and the above indexes in the observation group were lower than those in the control group (P<0.01). After treatment，scores of all SF-36 items in the observation group were increased compared with those before treatment (P<0.01); in the control group, the scores of general health (GH), social function (SF) and role-emotional (RE) were increased compared with those before treatment (P<0.05). After treatment, scores of all SF-36 items in the observation group were higher than those in the control group (P<0.01). The total effective rate in the observation group was 90.6% (29/32), which was higher than 46.9% (15/32) in the control group (P<0.01). CONCLUSION Wrist-ankle acupuncture has a significant clinical efficacy in the treatment of functional frequent PVCs. It can effectively improve symptoms such as chest tightness and palpitations, reduce 24-hour PVC count, and improve patients' quality of life.
Humans ; Acupuncture Therapy ; Male ; Female ; Middle Aged ; Adult ; Ventricular Premature Complexes/physiopathology* ; Ankle/physiopathology* ; Wrist/physiopathology* ; Acupuncture Points ; Treatment Outcome ; Aged ; Young Adult

Human ; Craniocerebral Trauma ; Coronary Artery Disease ; Heart Block ; Heart Failure

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*

The electrocardiographic analysis of heart blocks provides great opportunities for the discussion of mechanisms of electrical cardiac conduction, serving as “teachable moments” in medicine. Recognition of heart blocks can sometimes be a challenge as they can present in many forms, different severities and levels of blocks that present as varied patterns on electrocardiographic tracing. The ultimate key to correct diagnosis rests on adequate understanding of normal electrophysiology of the electrical system of the heart. While it is vital to recognize the pattern, we should always know and understand the physiology behind the pattern. This article presents a detailed analysis of a case of heart block which can easily be misinterpreted on first look. The case is featured not for its rarity but for the interesting concepts in cardiac electrophysiology that are highlighted. Navigation of the different elements of tracing can be an adventure and a great learning experience enjoyed by both students and experts.
Heart Block ; Electrocardiography

Background and Objective: Premature ventricular complex (PVC) burden exhibits one of three circadian types, classified as fast-type, slow-type, and independent-type PVC. It is unknown whether PVC circadian types have different heart rate variability (HRV) parameter values. Therefore, this study aimed to evaluate differences in HRV circadian rhythm among fast-, slow-, and independent-type PVC. Methods: This cross-sectional observational study consecutively recruited 65 idiopathic PVC subjects (23 fast-, 20 slow-, and 22 independent-type) as well as five control subjects. Each subject underwent a 24-hour Holter to examine PVC burden and HRV. HRV analysis included components that primarily reflect global, parasympathetic, and sympathetic activities. Repeated measures analysis of variance was used to compare differences in HRV circadian rhythm by PVC type. Results. The average PVC burden was 15.7%, 8.4%, and 13.6% in fast-, slow-, and independent-type idiopathic PVC subjects, respectively. Global, parasympathetic nervous system, and sympathetic nervous system HRV parameters were significantly lower in independenttype PVC versus fast- and slow-type PVC throughout the day and night. Furthermore, we unexpectedly found that tendency towards sympathetic activity dominance during nighttime was only in independent-type PVC. Conclusion The HRV parameters are reduced in patients with independent-type PVC compared to fast- and slowtype PVC. Future research is warranted to determine possible differences in the prognosis between the three PVC types.
Ventricular Premature Complexes ; Circadian Rhythm ; Autonomic Nervous System

Arrhythmia is an external manifestation of cardiac electrophysiological disorder. It exists in healthy people and patients with various heart diseases, which is often associated with other cardiovascular diseases. The contraction and diastole of myocardium are inseparable from the movement of ions. There are many ion channels in the membrane and organelle membrane of myocardium. The dynamic balance of myocardial ions is vital in maintaining myocardial electrical homeostasis. Potassium ion channels that have a complex variety and a wide distribution are involved in the whole process of resting potential and action potential of cardiomyocytes. Potassium ion channels play a vital role in maintaining normal electrophysiological activity of myocardium and is one of the pathogenesis of arrhythmia. Traditional Chinese medicine(TCM)has unique advantages in treating arrhythmia for its complex active components and diverse targets. A large number of TCM preparations have definite effect on treating arrhythmia-related diseases, whose antiarrhythmic mechanism may be related to the effect on potassium channel. This article mainly reviewed the relevant studies on the active components in TCM acting on different potassium channels to provide references for clinical drug use and development.
Humans ; Potassium Channels ; Medicine, Chinese Traditional ; Anti-Arrhythmia Agents/therapeutic use* ; Arrhythmias, Cardiac/drug therapy* ; Heart Diseases/drug therapy* ; Ions

Humans ; Anti-Arrhythmia Agents/therapeutic use* ; China ; Consensus

Humans ; Atrial Fibrillation/surgery* ; Anti-Arrhythmia Agents/therapeutic use* ; Treatment Outcome ; Catheter Ablation ; Recurrence