Myung-Yong Lee

Evaluation of mesotherapy as a transdermal drug delivery tool.

There has been no research about the exact mechanism of transdermal drug delivery during mesotherapy.

Intermittent, non cyclic severe mechanical aortic valve regurgitation.

Mechanical aortic prosthesis dysfunction can result from thrombosis or pannus formation. We describe an unusual case of intermittent, non cyclic mechanical aortic prosthesis dysfunction due to pannus formation with thrombus in the absence of systolic restriction of disk excursion, that presented with intermittent severe aortic regurgitation.

Spontaneous Transition of Double Tachycardias with Atrial Fusion in a Patient with Wolff-Parkinson-White Syndrome

Among patients with Wolff-Parkinson-White syndrome, atrioventricular reciprocating tachycardia (AVRT) and atrioventricular nodal reentrant tachycardia (AVNRT) can coexist in a single patient. Direct transition of both tachycardias is rare; however, it can occur after premature atrial or ventricular activity if the cycle lengths of the two tachycardias are similar. Furthermore, persistent atrial activation by an accessory pathway (AP) located outside of the AV node during ongoing AVNRT is also rare. This article describes a case of uncommon atrial activation by an AP during AVNRT and gradual transition of the two supraventricular tachycardias without any preceding atrial or ventricular activity in a patient with preexcitation syndrome.

Management of a Remnant Electrode in a Patient With Cardioverter-Defibrillator Infection After Refusal of Intravascular Electrode Removal

Treatments of choice for cardiac implantable electronic device (CIED) infections are the removal of the entire CIED system, control of infection, and new device implantation. Occasionally, a complete CIED removal can not be performed for several reasons, such as very old age, severe comobidity, limited life expectancy, or refusal by a patient. We encountered a male patient who developed traumatic CIED infection five years after cardioverter-defibrillator implantation. An intravenous electrode could not be removed by a simple transvenous extraction procedure, and he refused surgical removal of the remnant electrode. After control of local infection, the tips of the electrode were separated and buried between muscles, and the wound was closed with a local flap. CIED infection did not recur for 12 months even without relying on long-term antimicrobial treatment.

Radiofrequency Catheter Ablation of a Mahaim Fiber at Lateral Tricuspid Annulus

A 20 year-old male with recurrent syncope and wide QRS tachycardia with LBBB type underwent radiofrequency catheter ablation. Symptoms were present for 8 years. Electrophysiologic study revealed an antidromic atrioventricular reentrant tachycardia using an atrioventricular Mahaim fiber which conducted only anterogradely and resulted in LBBB QRS morphology on preexcitation. Decremental conduction was also noticed during single atrial extrastimulation and rapid atrial pacing. The atrial insertion of the Mahaim fiber was at the lateral tricuspid annulus and the ventricular insertion was at the lateral right ventricle near the tricuspid annulus. Discrete Mahaim fiber potential was recorded during atrial pacing and during tachycardia. Mahaim fiber was successfully ablated at the atrial side of lateral tricuspid annulus where the discrete Mahaim fiber potential was recorded. No complications occurred. Tachycardia did not recur during a follow-up of 6 months.