No abstract available.
Seizures* ; Sick Sinus Syndrome* ; Syncope

A 70-year-old woman developed sick sinus syndrome associated with thyrotoxicosis. Initial T3 was above 800ng/dl and TSH was below 0.05IU/ml. But sinus node dysfunction was resolved upon achieving a euthyroid state. This clinical course suggest that transient reversible sinus node dysfunction could be developed due to thyrotoxicosis.
Aged ; Female ; Humans ; Sick Sinus Syndrome* ; Thyrotoxicosis*

Pacemaker-mediated tachycardia(PMT) is a circus movement tachycardia that can occur in patients with dual chamber pacemaker with atrial sensing(VDD or DDD), when a ventricular depolarization, either spontaneous or paced, causes retrograde activation of the atrium. Recently, a number of pacemaker manufactures have incorporated in their devices a variety of relatively complex algorithms to prevent PMT. Despite these measures, PMT may still occur because of inappropriate programming or unpredictable variations of ventriculoatrial conduction. We report one case of PMT in a 78-year-old male who received DDD type pacemaker due to sick sinus syndrome. In this case, PMT was disappeared after reprogramming parameters of pacemaker and the application of PMT protection algorithm.
Aged ; Dichlorodiphenyldichloroethane ; Humans ; Male ; Sick Sinus Syndrome ; Tachycardia*

Symptomatic sinus bradycardia in adults with systemic lupus erythematosus (SLE) is rare. Here, we report a case of severe sinus bradycardia requiring temporary cardiac pacing in a SLE patient successfully treated using methylprednisolone pulse therapy.
Adult ; Bradycardia ; Humans ; Lupus Erythematosus, Systemic ; Methylprednisolone ; Sick Sinus Syndrome

Persistent left superior vena cava is a rare congenital anomaly resulting from the failure of the left cardinal vein to degenerate in utero. This anomaly was discovered in 0.3% of large autopsy examinations. Its most relevant clinical implication is the association with cardiac impulse formation and conduction problems. In the case of DDD pacemaker implantation for this anomaly, skillful manual stylet shaping is required or an active fixation device, for example a screw device for stable positioning of pacemaker leads, is needed. We experienced a case of sick sinus syndrome in a patient with persistent left superior and absent right superior vena cava in 72-year-old man. We successfully implanted a DDD type pacemaker through the left superior vena cava via coronary sinus. This is the first Korean report of a successfully implanted permanent pacemaker in a patient with persistent left superior and absent right superior vena cava.
Aged ; Autopsy ; Coronary Sinus ; Dichlorodiphenyldichloroethane* ; Humans ; Sick Sinus Syndrome ; Veins ; Vena Cava, Superior*

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

Clinical EPS was performed in 16 normal adults without evidence of conduction disease on the surface standard 12 lead electrocardiogram in order to provide normal electrophysiological values of the sinus node function and AV conduction. EPS was also performed in 15 patients with sick sinus syndrome and 10 patients with AV conduction disturbance to evaluate the clinical usefulness of EPS in detecting sinus node dysfunction and AV conduction disturbance. The results were as follows. 1) The results of sinus node function test in the normal group were m-SNRT 853+/-198msec(range 800-1,560msec), c-SNRT 230+/-66msec(range 120-370msec), and %m -SNRT/SCL 127+/-11%(range 114-149%). 2) In 15 patients with SSS, the M-SNRT were ranged from 1,270 to 12,330msec and 10 patients(66%) had significantly increased m-SNRT exceeding 1,560msec. The c-SNRT were ranged from 230 to 10,730msec and 13 patients(83%) had significantly increased c-SNRT exceeding 370msec. The % m-SNRT/SCL were ranged from 136 to 770% and 12 patients(80%) had significantly increased % m-SNRT/SCL exceeding 150%. 3) The SACT in normal group were 84+/-14msec(range 70-105msec) measured by continuous atrial pacing method and 80+/-19 msec(range 60-115msec) measured by atrial extrastimulation method. 4) In SSS, the SACT measured by continuous atrial pacing method was ranged from 80 to 1,050msec and 11/12 patients(92%) had significantly increased SACT exceeding 112 msec. The SACT measured by atrial extrastimulation method was ranged from 90 to 310msec and 7/8 patients(88%) had significantly increased SACT exceeding 118 msec. 5) C-SNRT, % m-SNRT/SCL, and SACT were more useful in detecting sinus node dysfunction than m-SNRT. 6) The AV conduction intervals in normal group were PA interval 17+/-6(range 5-25msec), AH interval 96+/-18 msec(range 70-135msec), and HV interval 46+/-7msec(range 35-55msec). 7) Rapid atrial pacing induced Wenckebach type second degree AV block proximal to H at pacing rate of 90 to 190/min in 14/16 normal adults. 2 patients maintained intact AV conduction upto maximum pacing rate of 200/min. 8) His bundle electrogram showed the site of AV block in 9 of 10 patients with AV conduction disturbances. The sites of AV block were AV nodal area 1 case, intraHis bundle 4 cases, and infraHis bundle 4 cases. 9) EPS provided a good supportive information that was useful in selecting pacemaker therapy in a patient with chronic bifascicular block who revealed prolonged HV interval and infraHis bundle block at a pacing rate of 70min. 10) The refractory periods of AV conduction system in normal group were AERP 274+/-54msec (range 170-410msec), AVN-FRp 467+/-74msec(range 285-600msec), AVN-ERP 341+76msec(range 190-460), and V-ERP 280+/-25msec(range 240-320msec).
Adult ; Atrioventricular Block ; Electrocardiography ; Electrophysiologic Techniques, Cardiac ; Humans ; Sick Sinus Syndrome ; Sinoatrial Node*

Desmopressin diacetate arginine vasopressin (DDAVP) is a synthetic analogue of the arginine vasopressin that is widely used in the treatment of diabetes insipidus, nocturnal enuresis, and polyuria. Although it is generally well-tolerated, DDAVP can cause hyponatremia, especially in elderly patients. There are many reports of DDAVP-induced hyponatremia, but there has been only one case report in which sinus node dysfunction was caused by severe hyponatremia. Here we report a case of sick sinus syndrome that occurred during an episode of severe hyponatremia induced by chronic use of desmopressin in a 91-year-old man who had nocturnal enuresis.
Aged ; Arginine Vasopressin ; Deamino Arginine Vasopressin* ; Diabetes Insipidus ; Humans ; Hyponatremia* ; Nocturnal Enuresis ; Polyuria ; Sick Sinus Syndrome*

BACKGROUND: The most widely utilized indexes of sinus node dysfunction are the sinus node recovery time (SNRT) and the corrected sinus node recovery time (CSNRT), which generally require catheterization. Adenosine has negative chronotropic effect on the sinoatrial node. Non-invasive and reliable sinus node function test with intravenous adenosine was investigated. METHODS AND RESULT: The clinical value of rapid intravenous injection of adenosine for assessing sinus node dysfunction was examined in 14 patients with sick sinus syndrome (SSS) and 31 controls. After prophylactic insertion of a temporary pacemaker in the right ventricle, overdrive suppression test was conducted using the standard technique and CSNRT was measured to evaluate the sinus node function. Then, the CSNRT after administration of an intravenous bolus of adenosine (6 mg and 12 mg) was measured. Post-adenosine corrected sinus node recovery time (ADO: SNRT) was calculated by subtracting the basal sinus cycle length from the longest sinus cycle length. When ADO: SNRT over 550 msec was assumed as an indicator of sinus node dysfunction, intravenous injection of 6 mg of adenosine had a sensitivity of 85% and specificity of 100%, and 12 mg of adenosine had a sensitivity of 100% and specificity of 90% for detection of sick sinus syndrome. There were significant differences in ADO: SNRT between patient and control group (6 mg 1501+/-1081 msec vs 64+/-109 msec; 12 mg 4005+/-2055 msec vs 216+/-315 msec, respectively). CONCLUSION: he ADO: SNRT was a highly sensitive and specific index for diagnosing sick sinus syndrome, and should be considered as an alternative to invasive testing in patients with suspected sick sinus syndrome.
Adenosine* ; Catheterization ; Catheters ; Diagnosis* ; Heart Ventricles ; Humans ; Injections, Intravenous ; Sensitivity and Specificity ; Sick Sinus Syndrome* ; Sinoatrial Node

Hyponatremia is the most common electrolyte abnormality in hospitalized patients and often presents no symptoms. The association between sinus node dysfunction and hyponatremia has rarely been reported. We describe a 77-year-old woman who developed reversible sinus node dysfunction accompanied by pulmonary edema that was associated with hyponatremia.
Aged ; Female ; Humans ; Hyponatremia* ; Pulmonary Edema* ; Sick Sinus Syndrome* ; Sinoatrial Node*