Successful Ablation for Atrial Tachycardia Originated from Sinus Venosa with Tachycardia-Induced Cardiomyopathy

A 74-year-old male suffering from congestive heart failure with atrial tachycardia (AT) with 2 : 1 atrioventricular conduction was admitted to our hospital. After the therapy with diuretics and β-blocker, his rapid AT was still sustained. He took the catheter ablation for his AT. Postpacing interval mapping from entrainment and noncontact mapping system revealed the mechanism of his AT, originated from sinus venosa. His AT was successfully terminated and eliminated by radiofrequency catheter ablation. After the successful ablation, he has been free from any AT, and his cardiac function was also improved

Pathological Findings of Cavotricuspid Isthmus Tissue Eighteen Days after Radiofrequency Catheter Ablation for Typical Atrial Flutter

A 75-year-old man with a prior myocardial infarction, who underwent a coronary artery bypass graft, suffered from typical atrial flutter. He underwent a cavotricuspid linear catheter ablation. Eighteen days after the ablation, he suddenly died. A transmural ablation line was created between the inferior vena cava and tricuspid annulus. Transmural loss of the cardiomyocytes and small clusters of coagulative necrosis were observed. Evidence of edema and a patchy hemorrage remained in the extracellular space

Stent placement to stabilize the left ventricular lead in the coronary sinus

Recently, cardiac resynchronization therapy (CRT. has been established as an effective treatment for drug-resistant heart failure with left ventricular dyssynchrony in patients with a New York Heart Association class (NYHA. of III-IV. Many cases have already been treated with CRT in Japan, however, some challenges still remains, such as difficult placement of the left ventricular (LV. lead at the target site, high threshold values even after successful placement of the LV lead, and the need to reposition of the LV lead due to diaphragmatic stimulation regardless of an appropriate threshold value. In particular, those cases with high threshold values at a distal site or those in which the lead is placed at a proximal site because of diaphragmatic stimulation are prone to lead dislodgement, and re-operation may be required. We report on a patient in whom stabilization of the LV lead was obtained by placing a coronary stent in the coronary sinus wall which resulted in an improved clinical course

Coronary Sinus Morphology in Patients with Posteroseptal Atrioventricular Accessory Pathways

Background: There have been numerous reports about coronary sinus (CS) anomalies related to posteroseptal accessory pathways (APs). The purpose of this study was to explore the diameter and morphology of CS in patients with posteroseptal APs. Methods: We performed direct CS angiography in 105 patients with 22 posteroseptal APs and 83 APs in other regions, and 25 control subjects. We compared the diameter of the CS ostium in all subjects, and assessed the correlation of the local activation time in the patients with posteroseptal APs. Results: The proximal size (diameter) of the CS in the patients with posteroseptal APs (13:6 ± 1:1 mm) was larger than that in the patients with other types of APs (10:2 ± 1:8 mm [p < 0:001]) and that in the control subjects (9:6 ± 1:5 mm [p < 0:001]). Dilatation of the CS in the patients with posteroseptal APs extended up to 20 mm inside the CS. In 15 (68%) of the patients with posteroseptal APs, the proximal site of the CS demonstrated a windsock appearance. Conclusions: We concluded that the larger size and the wind cone appearance of proximal CS were unique structural characteristics in most patients with posteroseptal APs

Matrix metalloproteinase-9 contributes to human atrial remodeling during atrial fibrillation

AbstractObjectivesThe purpose of this study was to determine the relationship between matrix metalloproteinases (MMPs)-1, -2, and -9, and tissue inhibitors of metalloproteinases (TIMP)-1 and the atrial structural remodeling during atrial fibrillation (AF).BackgroundMatrix metalloproteinases, a family of proteolytic enzymes and TIMPs, regulate the extracellular matrix turnover in cardiac tissue.MethodsTissue samples were obtained from 25 patients without a history of AF (regular sinus rhythm [RSR]) and 13 patients with AF (paroxysmal AF: 6, chronic AF 7) undergoing cardiac operations. We performed a western blotting analysis of the MMP-1, -2, and -9, and quantitatively analyzed the expression of the MMP-9 and TIMP-1 by real time polymerase chain reaction and ELISA. The localization of the MMP-9 was investigated by in situ zymography and immunohistochemistry.ResultsThe active form of the MMP-9 was significantly increased in the AF group in comparison to that in the RSR group (p < 0.05), but there were no differences between the groups in the protein level of the latent form of the MMP-9 and active and latent forms of the MMP-1 and MMP-2. We also demonstrated that the expression of the MMP-9 was significantly more increased in the atria of the AF group than in that of the RSR group for both the messenger ribonucleic acid (mRNA) (AF: RSR; 1: 1.5) and protein levels (AF: RSR; 3.9 ± 1.3 : 1.5 ± 0.4 ng/mg atrium). The expression level of the MMP-9 was also higher in the PAF group than in the RSR group, however, the diameter of the left atrium was similar in both groups. The gelatinase activity and left atrium diameter were positively correlated (p < 0.05, R = 0.766). The relative expression of the mRNA for the monocyte chemoattractant protein-1 was higher in the AF group than in the RSR group. Immunohistochemical analysis revealed that the MMP-9 was distributed within the perivascular area and under the epicardium of the atria.ConclusionsWe clearly showed that the expression of the MMP-9 increased in fibrillating atrial tissue, which may have contributed to the atrial structural remodeling and atrial dilatation during AF