Electrical injury is a serious public health problem. Heart is one of the most frequently affected organs. Electrical injury can cause life-threatening cardiac complications such as asystole, ventricular fibrillation, and myocardial rupture. In this case report, we present a 20-yr-old male patient with sick sinus syndrome that developed years after electrical injury.
Adult ; Atropine/diagnostic use ; Electric Injuries/complications* ; Electrocardiography ; Exercise Tolerance ; Human ; Male ; Pacemaker, Artificial ; Sick Sinus Syndrome/etiology* ; Sick Sinus Syndrome/physiopathology ; Sick Sinus Syndrome/therapy ; Sinoatrial Node/physiopathology ; Time Factors

BACKGROUND: Sinus node dysfunction (SND) is caused not only by intrinsic sinus node disease, but also by the extrinsic factors. Among the extrinsic factors, autonomic imbalance is most common. Symptomatic SND usually requires permanent pacemaker therapy. However, the clinical characteristics and patient response to medical therapy for hypervagotonic SND have not been properly clarified. MATERIALS AND METHODS: Thirty two patients (14 men, 18 women, 51 +/- 14 years) with hypervagotonic SND were included in this study, but those patients who had taken calcium antagonists, beta-blockers or other antiarrhythmic drugs were excluded. Hypervagotonic SND was diagnosed if the abnormal electrophysiologic properties of the sinus node were normalized after the administration of atropine (0.04 mg/kg). RESULTS: The presenting arrhythmias were 16 cases of sinus bradycardia (50.0%), 12 of sinus pause (37.5%), 3 of sinoatrial block (9.4%) and 1 of tachy-bradycardia (3.1%). Nine (28.1%) patients had hypertension, 7 (21.9%) smoked, 2 (6.3%) had diabetes mellitus, and 1 (3.1%) had hypercholesterolemia. Among the patients, 3 had no remarkable symptoms, 13 had dizziness, 7 had syncope, 3 had weakness and 6 had shortness of breath. Twenty five (78.1%) patients were treated with theophylline, 1 patient with tachy-bradycardia syndrome was treated with digoxin and propafenone, and 6 (18.8%) were treated with no medication. During the 43 +/- 28 month follow-up, 25 patients remained asymptomatic, but 6 who took no medication developed mild dizziness. One patient needed permanent pacemaker implantation owing to recurrent syncope despite of theophylline treatment. CONCLUSION: These results show that hypervagotonic SND has a benign course and most of the patients can be managed safely without implanting a pacemaker. (Ed note: I like the abstract. It is short and direct, as it should be.)
Dizziness/etiology ; Dyspnea/etiology ; Female ; Humans ; Male ; Middle Aged ; Muscle Weakness/etiology ; Sick Sinus Syndrome/*complications/drug therapy ; Syncope/etiology ; Theophylline/therapeutic use ; Vasodilator Agents/therapeutic use

PURPOSE: The identification of sick sinus syndrome (SSS) in patients with atrial flutter (AFL) is difficult before the termination of AFL. This study investigated the patient characteristics used in predicting a high risk of SSS after AFL ablation. MATERIALS AND METHODS: Out of 339 consecutive patients who had undergone radiofrequency ablation for AFL from 1991 to 2012, 27 (8%) had SSS (SSS group). We compared the clinical characteristics of patients with and without SSS (n=312, no-SSS group). RESULTS: The SSS group was more likely to have a lower body mass index (SSS: 22.5+/-3.2; no-SSS: 24.0+/-3.0 kg/m2; p=0.02), a history of atrial septal defects (ASD; SSS: 19%; no-SSS: 6%; p=0.01), a history of coronary artery bypass graft surgery (CABG; SSS: 11%; no-SSS: 2%; p=0.002), and a longer flutter cycle length (CL; SSS: 262.3+/-39.2; no-SSS: 243.0+/-40; p=0.02) than the no-SSS group. In multivariate analysis, a history of ASD [odds ratio (OR) 3.7, 95% confidence interval (CI) 1.2-11.4, p=0.02] and CABG (7.1, 95% CI 1.5-32.8, p=0.01) as well as longer flutter CL (1.1, 95% CI 1.0-1.2, p=0.04) were independent risk factors for SSS. CONCLUSION: A history of ASD and CABG as well as longer flutter CL increased the risk of SSS after AFL ablation. While half of the patients with SSS after AFL ablation experienced transient SSS, heart failure was associated with irreversible SSS.
Atrial Flutter/physiopathology/*surgery ; Catheter Ablation/*adverse effects ; Female ; Humans ; Male ; Middle Aged ; Multivariate Analysis ; Odds Ratio ; Risk Factors ; Sick Sinus Syndrome/*etiology/physiopathology ; Treatment Outcome

The effective therapeutics for the sinoatrial node (SAN) pacemaker dysfunction induced by SCN5A gene mutation this is still being explored recently. In this study, a two-dimensional experimental model of rabbit SAN-atrial cell system which proposed by Zhang et al., was used as a prototype, the gene mutation was considered, and effects of both the acid concentration and temperature were also introduced. The effects of acid concentration and temperature on sick sinus syndrome (SSS) at the tissue level were investigated by simulation. The results showed that the SAN abnormal pacemaker could be caused by the reduction of I(Na), which is induced by the two mutations of T220I and delF1617. The results also showed that if we properly adjusted the acid concentration and temperature of the system, not only could we increase the relevant currents, but also could we increase I(Na) which reduced by gene mutations, so that the pacemaking behavior of SAN tissue could return to normal state from abnormalities. The above simulation results imply that the abnormal pacemaking of SAN system may closely relate to the gene mutation of ion channel mutations, and the acid concentration and temperature may play a modulatory role. Our study could be useful for clinical medical diagnosis and therapy of cardiac disease.
Acids ; Animals ; Computer Simulation ; Mutation ; NAV1.5 Voltage-Gated Sodium Channel ; genetics ; Rabbits ; Sick Sinus Syndrome ; etiology ; genetics ; Sinoatrial Node ; pathology ; Temperature

The clinical data for a patient with sick sinus syndrome was retrospectively analyzed. The patient was treated because of his heart palpitations and the increased chest pain. The patient admitted to the hospital under consideration for the left atrial tumor dependent on the echocardiography findings. After the CT scan and the dynamic ECG examination, the patient successfully underwent the left atrial tumor resection, atrial septal repair and cardiac pacing lead installation. The postoperative pathological diagnosis showed that the infective endocarditis and left atrial thrombus in left atrium was cured. The patient was discharged after postoperative anti-inflammatory therapy. By analyzing the reasons for misdignosis before or during surgery, the possible mechanisms for left atrial subendocardial thrombus have been found. This study suggests that it is necessary to combine imaging diagnosis and clinical observations to distinguish tumor from excrescence.
Anti-Inflammatory Agents ; therapeutic use ; Arrhythmias, Cardiac ; etiology ; surgery ; Atrial Septum ; surgery ; Computed Tomography Angiography ; Diagnosis, Differential ; Diagnostic Errors ; Echocardiography ; Endocarditis ; diagnosis ; therapy ; Heart Atria ; diagnostic imaging ; surgery ; Heart Diseases ; etiology ; surgery ; Heart Neoplasms ; complications ; diagnostic imaging ; surgery ; Humans ; Male ; Pacemaker, Artificial ; Retrospective Studies ; Sick Sinus Syndrome ; etiology ; surgery ; Thrombosis ; etiology ; surgery