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Yoshiaki Kaneko

Publications and source records attributed to Yoshiaki Kaneko.

8 recordsLinked to original sources
PubMed2004

Myocardial bundles with slow conduction properties are present on the left interventricular septal surface of normal human hearts.

INTRODUCTION: The aim of this study was to examine the electrophysiologic characteristics of the normal left interventricular septum (LIVS). METHODS AND RESULTS: We explored the LIVS in search of endocardial potentials following ventricular electrograms during sinus rhythm in 28 patients without structural heart disease. In all patients, low-frequency (mean amplitude: 0.81 +/- 0.33 mV) systolic potentials (LA1) were detected in a basal-to-apical activation sequence (earliest to latest QRS-LA1 interval: 93.3 +/- 10.8 ms to 127.1 +/- 16.6 ms). Programmed stimulation demonstrated decremental conduction properties, and the effective refractory period of the tissue between the ventricular electrogram and LA1 at baseline (376.7 +/- 48.8 ms) was significantly prolonged by disopyramide (421.3 +/- 54.1 ms, P < 0.05 vs baseline). In 21 patients (75%), diastolic potentials (LA2) morphologically similar to LA1 (mean amplitude: 0.52 +/- 0.17 mV) were detected in an apical-to-basal activation sequence (earliest to latest QRS-LA2 interval: 368.9 +/- 32.4 ms to 440.7 +/- 45.8 ms). Para-Hisian pacing with capture of the His bundle showed shorter S-LA1 and S-LA2 intervals compared to the beats without His-bundle capture but with ventricular capture (156.3 +/- 11.2 ms vs 183.2 +/- 12.3 ms, and 385.7 +/- 21.6 ms vs 397.4 +/- 23.4 ms, respectively, P < 0.0001). At the same rate, the LA1-LA2 interval was significantly shorter during right ventricular apical than atrial overdrive pacing (220.4 +/- 23.1 ms vs 261.4 +/- 30.7 ms, P < 0.0001). CONCLUSION: Unique myocardial bundles with slow conduction properties and various electrical connections with the specialized conduction system may exist in the LIVS of normal human hearts.

Adult↗
PubMed2004

Coronary sinus recordings of double potentials associated with retrograde conduction through left atrioventricular accessory pathways.

INTRODUCTION: In some patients with left AV accessory pathway (AP), double potentials are recorded along the coronary sinus (CS) during retrograde AP conduction only. This electrophysiologic study was performed to clarify the origin and clinical significance of double potentials in 11 patients. METHODS AND RESULTS: The direction of activation of the first, relatively blunt component (DP1) was lateral to septal in 5 patients with anterior or anterolateral AP, centrifugal in 2 patients with posterior or posterolateral AP, and septal to lateral in 4 patients with posteroseptal AP, suggesting the earliest activation of DP1 was near the AP. The direction of activation of the second, sharper potentials (DP2) were septal to lateral in all patients. The double potentials were fused in the paraseptal CS region. Pacing from the lateral CS musculature or lateral left atrium reproduced the double potentials. The effective refractory period of the double potentials was reached by ventricular extrastimulation, and the left atrial deflection preceded the double potentials, excluding a ventricular or AP origin. CONCLUSION: In patients with connections between the paraseptal CS musculature and left atrium but no connections more laterally, retrograde left AP conduction is associated with double potentials in the CS recordings. The double potentials represent activation of the left atrial insertion of the AP (DP1) and later activation of the CS musculature (DP2) via connections between the paraseptal CS musculature and left atrium, respectively. The activation pattern of DP1 depends on AP location, thus providing important information for AP localization during CS mapping.

Action Potentials↗
PubMed2004

Electrophysiological characteristics and radiofrequency ablation of accessory pathways with slow conductive properties.

BACKGROUND: Atrioventricular accessory pathways (AP) with unusually long ventriculo-atrial (VA) conduction times are present in a significant subset of patients with the Wolff-Parkinson-White (WPW) syndrome, not including patients with the permanent form of atrioventricular junctional reciprocating tachycardia. METHODS AND RESULTS: We compared the electrophysiological characteristics and outcomes after radiofrequency (RF) ablation in 34 patients with the WPW syndrome, a VA interval >80 ms, and paroxysmal tachycardia with an RP/PR ratio <1 (the slow group), vs 80 patients with WPW syndrome and a VA interval <80 ms (the fast group). AP were found in the posteroseptal region significantly more often in the slow than in the fast group. In addition, the decremental conductive properties of the AP were more common in the slow than in the fast group. Catheter ablation of AP was highly successful in both groups, although ablation required a greater number of RF applications and longer procedure times in the slow group, especially for AP with decremental conductive properties. CONCLUSIONS: A posteroseptal AP location was more common in AP associated with long conduction times than in AP with typical conductive properties. Both types of AP were successfully ablated, although the slow group required longer procedures and more RF energy deliveries.

Adolescent↗
PubMed2002

[Arrhythmias in cardiomyopathies].

The purpose of this review is to discuss the pathophysiology of the complicated arrhythmias or sudden cardiac death, the appropriate risk stratification and current treatment options in patients with dilated cardiomyopathy, hypertrophic cardiomyopathy and arrhythmogenic right ventricular cardiomyopathy. It is important to know possible risk factors on risk stratification for a high-risk group in each cardiomyopathy. Therapeutic strategies, including amiodarone, implantable-cardioverter-defibrillator, may contribute the prevention of sudden cardiac death.

Amiodarone↗