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Sudden hemodynamic collapse occurred in a 20-year-old man after an Emergency Department visit with a complaint of dizziness and chest discomfort. A left atrial myxoma was demonstrated by echocardiography. Resuscitation procedures followed by surgical repair resulted in an excellent outcome. Although sudden death is a serious manifestation of cardiac myxoma, reports of survivors of near sudden death caused by this tumor have been rare.

An 82-year-old woman with 2:1 atrioventricular block underwent a pacemaker implantation procedure, but a tined lead became entrapped by the Chiari network. All manipulations failed to achieve release of the electrode, by which the atrial electrical potential could be recorded. Tines equipped near the tip of a pacemaker lead are intended to prevent dislodgment, but entrapment of the tined tip by intracardiac structures is probable. Together with another screw-in ventricular lead, this entrapped tined lead could act as a dual chamber pacemaker in VDD mode.

A 57-year-old man, who had undergone aorto-coronary bypass surgery 4 years before when the shape of the ascending aorta had been normal, had a unique orange-shaped aortic root aneurysm associated with severe aortic regurgitation and congestive heart failure. Replacement of the aneurysm and the aortic valve was successfully carried out, and histopathological examination revealed that the aneurysm was caused by aortitis syndrome.

We examined enfrainment by ventricular pacing in six patients during orthodromic atrioventricular reentrant tachycardia (AVRT) utilizing a left-sided lateral accessory pathway. Constant fusion and progressive fusion were demonstrated in all patients by left ventricular pacing during tachycardia, but in none of the patients by right ventricular pacing. When left ventricular pacing was performed during AVRT, the antidromic wave front from the pacing impulse (n) collided with the orthodromic wave front of the previous pacing beat (n - 1) within the ventricle, therefore, constant fusion and progressive fusion were demonstrated in the surface electrocardiographic QRS complexes. On the other hand, when right ventricular pacing was performed during orthodromic AVRT, the antidromic wave front from the pacing impulse (n) collided with the orthodromic wave front of the previous paced beat (n - 1) within the normal atrioventricular pathway, and constant fusion and progressive fusion were therefore not demonstrated. These phenomena were explained by the relationship of the ventricular pacing site and the reentrant circuit. This study demonstrates the importance of the pacing site in manifest entrainment of orthodromic AVRT during ventricular pacing.