Are you Michiharu Senga?

Claim your profile

Publications (2)2.45 Total impact

  • Article: Clinical features of patients with left atrial thrombus undergoing anticoagulant therapy.
    [show abstract] [hide abstract]
    ABSTRACT: Left atrial (LA) thrombus was sometimes found by transesophageal echocardiography (TEE) in non-valvular atrial fibrillation (AF), even in the setting of continuous warfarin therapy. A D-dimer cutoff level of 0.50 μg/mL appears to be a useful marker to rule out venous vein thrombosis. This study analyzed the clinical features of patients with LA thrombi who received anticoagulant therapy and whether the D-dimer test is useful to exclude LA thrombus. Two hundred twenty-five consecutive patients with AF (149 with paroxysmal and 76 with persistent) were enrolled. All patients received continuous warfarin therapy with the prothrombin time-international normalized ratio (PT-INR) between 1.6 and 3.0 for more than 3 months and TEE was performed. LA thrombi were present in 23 and absent in 202 patients. Age, gender, and PT-INR (1.96 ± 0.59 vs. 1.98 ± 0.53) were not different between the two groups. Persistent AF (65 vs. 30%; p < 0.005), LA diameter (44 ± 5 vs. 40 ± 7 mm; p < 0.005), ejection fraction (57 ± 13 vs. 65 ± 9%; p < 0.005), brain natriuretic peptide levels (203 ± 209 vs. 105 ± 166 pg/mL; p < 0.05), D-dimer (0.55 ± 0.70 vs. 0.16 ± 0.20 μg/mL; p < 0.001), LA appendage flow velocity (33 ± 15 vs. 54 ± 19 cm/s; p < 0.001), CHADS(2) scores (2 ± 1 vs. 1 ± 1; p < 0.005), and CHA(2)DS(2)-VASc scores (3 ± 2 vs. 2 ± 1; p < 0.005) were significantly different in both groups. Although multivariate analysis showed that D-dimer and LA appendage flow velocity were significant independent predictors of LA thrombus, D-dimer levels below 0.5 μg/mL were found in 19 of 23 patients with LA thrombi. D-dimer levels below 0.5 μg/mL is not enough to rule out LA thrombus in AF patients with well-controlled anticoagulation.
    Journal of Interventional Cardiac Electrophysiology 12/2011; 34(1):59-63. · 1.17 Impact Factor
  • Article: Efficacy of linear block at the left atrial roof in atrial fibrillation.
    [show abstract] [hide abstract]
    ABSTRACT: After extensive encircling of ipsilateral pulmonary vein isolation (EEPVI) for atrial fibrillation (AF), we sometimes observe AF recurrence, or the occurrence of atrial tachycardia originating from the left atrium. This study examined the efficacy of additional linear ablation at the left atrial (LA) roof in combination with EEPVI to prevent arrhythmia recurrences. This study included 104 patients with drug-refractory AF (75 with paroxysmal, 29 with persistent). The patients in Group A (n=70) underwent EEPVI treatment alone, and the patients in Group B (n=34) underwent linear ablation at the LA roof in addition to EEPVI treatment. At 1, 3, 6, and 12 months after ablation, patients underwent clinical review and 24-h ambulatory electrocardiogram monitoring to identify asymptomatic arrhythmias. Follow-up included daily trans-telephonic event monitoring, transmitted irrespective of the patient's symptoms. At 12 months, 57% of Group A and 79% of Group B were free of arrhythmias (p<0.05). Cox regression analysis demonstrated that among the variables of age, sex, duration of AF, types of AF (paroxysmal or persistent), LA size, ejection fraction, existence of hypertension, ischemic heart disease, valvular heart disease, history of stroke, and the ablation technique, only the ablation technique of the linear block at the LA roof was the independent predictor of arrhythmia-free recovery after ablation. EEPVI in combination with the linear ablation at the LA roof is associated with an improved clinical outcome compared with EEPVI alone.
    Journal of Cardiology 01/2010; 55(3):322-7. · 1.28 Impact Factor