Takayoshi Toba

Impact of esophageal temperature monitoring guided atrial fibrillation ablation on preventing asymptomatic excessive transmural injury

Even with the use of a reduced energy setting (20–25 W), excessive transmural injury (ETI) following catheter ablation of atrial fibrillation (AF) is reported to develop in 10% of patients. However, the incidence of ETI depends on the pulmonary vein isolation (PVI) method and its esophageal temperature monitor setting. Data comparing the incidence of ETI following AF ablation with and without esophageal temperature monitoring (ETM) are still lacking.

Impact of CD14 ++ CD16 + monocytes on coronary plaque vulnerability assessed by optical coherence tomography in coronary artery disease patients with well-regulated lipid levels

BACKGROUND AND AIMS This study examined the impact of CD14++CD16+ monocytes on coronary plaque vulnerability, as assessed by optical coherence tomography (OCT), and investigated their association with daily glucose fluctuation. Although increased CD14++CD16+ monocyte levels have been reported to increase cardiovascular events, their impact on coronary plaque vulnerability in coronary artery disease (CAD) patients with or without diabetes mellitus (DM) remains unclear. METHODS This prospective observational study included 50 consecutive patients with CAD, receiving lipid-lowering therapy and undergoing coronary angiography and OCT. Patients were divided into 3 tertiles according to the CD14++CD16+ monocyte percentages assessed by flow cytometry. Standard OCT parameters were assessed for 97 angiographically intermediate lesions (diameter stenosis: 30-70%). Daily glucose fluctuation was analyzed by measuring the mean amplitude of glycemic excursion (MAGE). RESULTS CD14++CD16+ monocytes negatively correlated with fibrous cap thickness (r = -0.508, p < 0.01). The presence of thin-cap fibroatheroma (TCFA) was increased stepwise according to the tertile of CD14++CD16+ monocytes (0 [tertile 1] vs. 5 [tertile 2] vs. 10 [tertile 3], p < 0.01). CD14++CD16+ monocytes were a significant determinant of TCFA (OR 1.279, p = 0.001). In non-DM patients, a significant relationship was found between CD14++CD16+ monocytes and MAGE (r = 0.477, p = 0.018). CONCLUSIONS CD14++CD16+ monocytes were associated with coronary plaque vulnerability in CAD patients with well-regulated lipid levels both in DM and non-DM patients. Cross-talk between glucose fluctuation and CD14++CD16+ monocytes may enhance plaque vulnerability, particularly in non-DM patients. CD14++CD16+ monocytes could be a possible therapeutic target for coronary plaque stabilization.

The association between wedging of the aorta and cardiac structural anatomy as revealed using multidetector-row computed tomography

The aortic root is wedged within the cardiac base. The precise extent of aortic wedging, however, and its influence on the surrounding cardiac structures, has not been systematically investigated. We analysed 100 consecutive patients, who underwent coronary arterial computed tomographic angiography. We assessed the extent of aortic wedging by measuring the vertical distance between the non‐adjacent aortic sinus and the inferior epicardium. A shorter distance indicates deeper aortic wedging. We assessed the tilt angle and diameter of the ascending aorta, the relative heights of the left atrial roof and the oval fossa, the shape of the proximal right coronary artery, the angle of the aorta relative to the left ventricular axis, and the lung volume. The mean extent of wedging was 42.7 ± 9.8 mm. Multivariate analysis revealed that ageing, male gender, increased body mass index, patients without cardiomyopathy, the extent of tilting and dilation of the ascending aorta, and lung volume were all independent predictors for deeper aortic wedging (R2 = 0.7400, P < 0.0001). The extent of wedging was additionally correlated with a relatively high left atrial roof (R2 = 0.1394, P < 0.0001) and oval fossa (R2 = 0.1713, P < 0.0001), the shepherds crook shape of the proximal right coronary artery (R2 = 0.2376, P < 0.0001), and the narrowness of the angulation of the root relative to the left ventricular axis (R2 = 0.2544, P < 0.0001). In conclusion, ageing, male gender, obesity, background cardiac disease, aortic tilting and dilation, and lung volume are all correlated with the extent of wedging of the aortic root within the cardiac base.

Incidence of esophageal injury after pulmonary vein isolation in patients with a low body mass index and esophageal temperature monitoring at a 39 °C setting

Esophageal injury following catheter ablation of atrial fibrillation (AF) is reported to occur in 35% of patients. Even with a low energy setting (20–25 W), lesions develop in 10% of patients. Body mass index (BMI) has been reported to be a predictor of esophageal injury, indicating that patients with a low BMI (<24.9 kg/m2) are at a higher risk. We hypothesized that catheter ablation with a lower energy setting of 20 W controlled by esophageal temperature monitoring (ETM) at 39 °C could prevent esophageal injury even in patients with a BMI <24.9 kg/m2.

Visualizing radiofrequency lesions using delayed-enhancement magnetic resonance imaging in patients with atrial fibrillation: A modification of the method used by the University of Utah group

Atrial tissue fibrosis has previously been identified using delayed‐enhancement MRI (DE‐MRI) in patients with atrial fibrillation (AF). Although the clinical importance of DE‐MRI is well recognized, the visualization of atrial fibrosis and radiofrequency (RF) lesions has still not been achieved in Japan, primarily because of the differences in contrast agents, volume‐rendering tools, and technical experience. The objective of this study was to visualize RF lesions by using commercially available tools.

The differences between bisecting and off‐center cuts of the aortic root: The three‐dimensional anatomy of the aortic root reconstructed from the living heart

It is axiomatic that the diameter of the virtual basal ring of the aortic root, which is elliptical rather than circular, will differ when assessed using between bisecting as opposed to off‐center cuts. Such differences, however, which pertain directly to echocardiographic assessments of the so‐called valvar annulus, have yet to be systematically explored.

Diversity and Determinants of the Three-dimensional Anatomical Axis of the Heart as Revealed Using Multidetector-row Computed Tomography

The location of the heart within the thorax varies significantly between individuals. The resultant diversity of the anatomical cardiac long axis, however, and its determinants, have yet to be systematically investigated. We enrolled 100 consecutive patients undergoing coronary arterial computed tomographic angiography, decomposing the vector of the anatomical cardiac long axis by projecting it to horizontal, frontal, and sagittal planes. The projected vectors on each plane were then converted into three rotation angles using coordinate transformation. We then measured the extent of aortic wedging, using the vertical distance between the inferior margins of the non‐adjacent aortic sinus and the epicardium. We took the aortic root rotation angle to be zero when an “en face” view of the right coronary aortic sinus was obtained in the frontal view, defining leftward rotation to be positive. The mean horizontal, frontal, and sagittal rotation angles were 48.7° ± 9.5°, 52.3° ± 12.0°, and 34.0° ± 11.2°, respectively. The mean extent of aortic wedging, and the aortic root rotation angle, were 42.7 ± 9.8 mm, and 5.3° ± 16.4°. Horizontal rotation of the anatomical axis was associated with leftward and ventral rotation, and vice versa. Multivariate analysis showed aortic root rotation to be associated with horizontal cardiac rotation, while aortic wedging is associated with frontal and sagittal cardiac rotation. We have quantified the marked individual variation observed in the anatomical axis of the living heart, identifying the different mechanisms involved in producing the marked three‐dimensional diversity of the living heart. Anat Rec, 300:1083–1092, 2017.

Visualization of the radiofrequency lesion after pulmonary vein isolation using delayed enhancement magnetic resonance imaging fused with magnetic resonance angiography.

The radiofrequency (RF) lesions for atrial fibrillation (AF) ablation can be visualized by delayed enhancement magnetic resonance imaging (DE‐MRI). However, the quality of anatomical information provided by DE‐MRI is not adequate due to its spatial resolution. In contrast, magnetic resonance angiography (MRA) provides similar information regarding the left atrium (LA) and pulmonary veins (PVs) as computed tomography angiography. We hypothesized that DE‐MRI fused with MRA will compensate for the inadequate image quality provided by DE‐MRI.

Novel Compression Tool to Prevent Hematomas and Skin Erosions After Device Implantation.

BACKGROUND The incidence of hematoma formation following implantation of a cardiovascular implantable electronic device (CIED) is estimated to be 5% even if a pressure dressing is applied. It is unclear whether a pressure dressing can really compress the pocket in different positions. Furthermore, the adhesive tape for fixing pressure dressings can tear the skin. We developed a new compression tool for preventing hematomas and skin erosions. METHODS AND RESULTS We divided 46 consecutive patients receiving anticoagulation therapy who underwent CIED implantation into 2 groups (Group I: conventional pressure dressing, Group II: new compression tool). The pressure on the pocket was measured in both the supine and standing positions. The incidence of hematomas was compared between the 2 groups. The pressure differed between the supine and standing positions in Group I, but not in Group II (Group I: 14.8±7.1 mmHg vs. 11.3±9.9 mmHg, P=0.013; Group II: 13.5±2.8 mmHg vs. 13.5±3.5 mmHg, P=0.99). The incidence of hematomas and skin erosions was documented in 2 (8.7%) and 3 (13%) Group I patients, respectively. No complications were documented in Group II. CONCLUSIONS The new compression tool can provide adequate continuous pressure on the pocket, regardless of body position. This device may reduce the incidence of hematomas and skin erosions after CIED implantation.

Comparison of the 9-month intra-stent conditions and 2-year clinical outcomes after Resolute zotarolimus-eluting stent implantation between 3-month and standard dual antiplatelet therapy

BACKGROUND The use of short-duration dual antiplatelet therapy (DAPT) remains controversial. To investigate efficacy and safety of short-duration DAPT, we performed a detailed comparison of intra-stent conditions by optical coherence tomography (OCT) after second-generation drug-eluting stent implantation with short-term and standard DAPT. METHODS AND RESULTS Eighty-two consecutive patients with stable angina pectoris who received Resolute zotarolimus-eluting stents (R-ZESs; Medtronic Cardiovascular, Santa Rosa, CA, USA) were enrolled. Patients were assigned to 3-month (3M group: 41 patients) and standard (standard group: 41 patients) DAPT. In the 3M group, clopidogrel was discontinued 3 months after stent implantation. In the standard group, DAPT was maintained until follow-up OCT. At 9 months, neointimal proliferation was significantly larger in the 3M group, but there were no significant between-group differences in the proportion of uncovered and malapposed strut. The prevalence of abnormal intra-stent tissue (AIT) at 9 months was equivalent between groups. A multiple regression analysis revealed malapposition at 9 months as the strongest independent predictor of AIT at 9 months, and the prevalence of AIT was not associated with DAPT duration. Over 2 years, cardiac events were equal between groups; however, major bleeding was higher tendency in the standard group than in the 3M group. CONCLUSION This OCT study indicated that reducing DAPTs duration may provide acceptable arterial healing in patients with implanted R-ZESs.