A Case of Lown-Ganong-Levine Syndrome: Due to an Accessory Pathway of James Fibers or Enhanced Atrioventricular Nodal Conduction (EAVNC)?

BACKGROUND Lown-Ganong-Levine syndrome, includes a short PR interval, normal QRS complex, and paroxysmal tachycardia. The pathophysiology of this syndrome includes an accessory pathway connecting the atria and the atrioventricular (AV) node (James fiber), or between the atria and the His bundle (Brechenmacher fiber). Similar features are seen in enhanced atrioventricular nodal conduction (EAVNC), with the underlying pathophysiology due to a fast pathway to the AV node, and with the diagnosis requiring specific electrophysiologic criteria. CASE REPORT A 17-year-old man presented with a history of recurrent narrow-complex and wide-complex tachycardia on electrocardiogram (ECG). An electrophysiologic study showed an unusually short atrial to His (AH) conduction interval and a normal His to ventricle (HV) interval, without a delta wave. Two stable AH intervals coexisted in the same atrial pacing cycle length. In the recovery curve study, this pathway had a flat conduction curve without an AH increase until the last 60 ms, before reaching the effective refractory period. These ECG changes did not respond to an adenosine challenge. When this pathway became intermittent, there was a paradoxical response to adenosine challenge with conduction via a short AH interval, but without conduction block. Catheter ablation of the AV nodal region resulted in a normalized AH interval, decremental conduction properties, and resulted in a positive response to an adenosine challenge. CONCLUSIONS In this case of Lown-Ganong-Levine syndrome, electrophysiologic studies supported the role of the accessory pathway of James fibers.

Electrocardiographic changes in patients with spontaneous pneumothorax.

The aim of the study was to evaluate the prevalence of electrocardiography (ECG) abnormalities in subjects with spontaneous pneumothorax. Forty consecutive patients (mean age 43.7 +/-19.1 years) with spontaneous pneumothorax participated in the study. There were 22 cases of left-sided and 18 cases of right-sided pneumothorax. The mean relative volume of pneumothorax was 51.4 +/-24.7% according to the Light's index and 53.5 +/-22.9% according to the Rhea method. Heart rate was significantly higher in patients with pneumothorax than after lung re-expansion (91 +/-20 bpm vs. 72 +/-16 bpm; P<0.001). Abnormal left axis deviation was found in 3 patients with left-sided and in 1 with right-sided pneumothorax, while abnormal right axis deviation was found in 2 patients with left-sided pneumothorax. Relevant QRS abnormalities (incomplete RBBB and T-wave inversion) were found in 4 patients (10%). QRS amplitude in V2-V6 leads was significantly decreased in left-sided pneumothorax, while the right-sided pneumothorax was associated with an increase in QRS amplitude in V5-V6. We conclude that ECG in subjects with pneumothorax often reveals significant abnormalities. The most significant abnormalities were seen in patients with massive right-sided pneumothorax.

[Clinical picture of pathological conditions with electrocardiographic features of the LGL syndrome]. / Obraz kliniczny zespolów chorobowych przebiegajacych z elektrokardiograficznymi cechami zespolu LGL.

Three cases of the LGL syndrome are reported. In the first case the syndrome was associated with hyperthyroidism, in the second case ECG abnormalities suggested focal myocardial ischaemia, in the third case pre-excitation coexisted with combined valvular heart disease. Attention is called to frequent occurrence of the pre-exitation syndrome with certain disease entities.