Akinori Sugano

Complex Left Atrial Appendage Morphology and Left Atrial Appendage Thrombus Formation in Patients With Atrial Fibrillation

Background—In patients with atrial fibrillation (AF), most thrombus forms in the left atrial appendage (LAA). However, the relation of LAA morphology with LAA thrombus is unknown. Methods and Results—We prospectively enrolled 633 consecutive patients who were candidates for catheter ablation for symptomatic drug-resistant AF. Transesophageal echocardiography (TEE) was performed to assess LAA thrombus. LAA structure was assessed by 3-dimensional TEE. LAA orifice area, depth, volume, and number of lobes were measured on reconstructed 3-dimensional images. Clinical characteristics and echocardiographic measures were compared to determine variables predicting LAA thrombus. Excluded were 69 (10.9%) patients who met the exclusion criteria. Finally, this study comprised 564 patients, of whom LAA thrombus was observed in 36 (6.4%) patients. Multivariate analysis revealed CHADS2 (Congestive heart failure, Hypertension Age>75, Diabetes mellitus and prior Stroke or transient ischemic attack) score (P=0.002), left ventricular ejection fraction (P=0.01), degree of spontaneous echo contrast (P=0.02), left atrial volume (P=0.02), and number of LAA lobes (P<0.001) to be independently associated with thrombus formation. Most patients with LAA thrombus (32/34, 94.4%) had ≥3 LAA lobes, whereas LAA thrombus was observed in only 2 (0.7%) of 296 patients with 1 or 2 lobes. LAA volume significantly decreased in patients maintaining sinus rhythm after catheter ablation (P=0.0009). Number of LAA lobes did not change in any patient. Conclusions—Complex LAA morphology characterized by an increased number of LAA lobes was associated with the presence of LAA thrombus independently of clinical risk and blood stasis. This study suggests that LAA morphology might be a congenital risk factor for LAA thrombus formation in patients with AF.

Novel Mechanistic Insights Into Atrial Functional Mitral Regurgitation – 3-Dimensional Echocardiographic Study –

BACKGROUND Left atrial remodeling caused by persistent atrial fibrillation (AF) causes atrial functional mitral regurgitation (MR), even though left ventricular (LV) remodeling and organic changes of the mitral leaflets are lacking. The detailed mechanism of atrial functional MR has not been fully investigated. METHODSANDRESULTS Of 1,167 patients with AF who underwent 3D transesophageal echocardiography, 75 patients were retrospectively selected who developed no, mild, or moderate-to-severe atrial functional MR (n=25 in each group) despite an LV ejection fraction ≥50% and LV volumes within the normal range. Mitral valve morphology and dynamics were analyzed. Patients with moderate-to-severe MR had a larger mitral annulus (MA) area, smaller MA area fraction, and greater nonplanarity angle and tethering angle of the posterior mitral leaflet (PML) compared with other groups (all P<0.001). In the multiple regression analysis, the MA area, MA area fraction, nonplanarity angle, and PML angle were independent determinants of the effective regurgitant orifice area of MR after adjusting for LV parameters (adjusted R(2)=0.725, P<0.001). The PML angle and MA area had a higher standardized regression coefficient (β=0.403, P<0.001, β=0.404, P<0.001, respectively) than the other variables. CONCLUSIONS Functional atrial MR in persistent AF is caused by not only MA dilatation, but also by multiple factors including the MA contractile dysfunction, disruption of the annular saddle shape, and atriogenic PML tethering. (Circ J 2016; 80: 2240-2248).

Enhancement patterns detected by multidetector computed tomography are associated with microvascular obstruction and left ventricular remodelling in patients with acute myocardial infarction

AIMS This study evaluated the clinical value of myocardial contrast-delayed enhancement (DE) with multidetector computed tomography (MDCT) for detecting microvascular obstruction (MVO) and left ventricular (LV) remodelling revealed by DE magnetic resonance imaging after acute myocardial infarction (AMI). METHODS AND RESULTS In 92 patients with first AMI, MDCT without iodine reinjection was performed immediately following successful percutaneous coronary intervention (PCI). Delayed-enhancement magnetic resonance imaging performed in the acute and chronic phases was used to detect MVO and LV remodelling (any increase in LV end-systolic volume at 6 months after infarction compared with baseline). Patients were divided into two groups according to the presence (n = 33) or absence (n = 59) of heterogeneous enhancement (HE). Heterogeneous enhancement was defined as concomitant presence of hyper- and hypoenhancement within the infarcted myocardium on MDCT. Microvascular obstruction and LV remodelling were detected in 49 (53%) and 29 (32%) patients, respectively. In a multivariable analysis, HE and a relative CT density >2.20 were significant independent predictors for MVO [odds ratio (OR) 13.5; 95% confidence interval (CI), 2.15-84.9; P = 0.005 and OR 12.0; 95% CI, 2.94-49.2; P < 0.001, respectively). The presence of HE and relative CT density >2.20 showed a high positive predictive value of 93%, and the absence of these two findings yielded a high negative predictive value of 90% for the predictive value of MVO. Heterogeneous enhancement was significantly associated with LV remodelling (OR 6.75; 95% CI, 1.56-29.29; P = 0.011). CONCLUSION Heterogeneous enhancement detected by MDCT immediately after primary PCI may provide promising information for predicting MVO and LV remodelling in patients with AMI.

Utility of Nutritional Screening in Predicting Short-Term Prognosis of Heart Failure Patients

Controlling nutritional status (CONUT) uses 2 biochemical parameters (serum albumin and cholesterol level), and 1 immune parameter (total lymphocyte count) to assess nutritional status. This study examined if CONUT could predict the short-term prognosis of heart failure (HF) patients.A total of 482 (57.5%) HF patients from the Ibaraki Cardiovascular Assessment Study-HF (n = 838) were enrolled (298 men, 71.7 ± 13.6 years). Blood samples were collected at admission, and nutritional status was assessed using CONUT. CONUT scores were defined as follows: 0-1, normal; 2-4, light; 5-8, moderate; and 9-12, severe degree of undernutrition. Accordingly, 352 (73%) patients had light-to-severe nutritional disturbances. The logarithmically transformed plasma brain natriuretic peptide (log BNP) concentration was significantly higher in the moderate-severe nutritional disturbance group (2.92 ± 0.42) compared to the normal group (2.72 ± 0.45, P < 0.01). CONUT scores were significantly higher in the in-hospital death patients [4 (3-8), n = 14] compared with patients who were discharged following symptom alleviation [3 (1-5), n = 446, P < 0.05]. With the exception of transferred HF patients (n = 22), logistic regression analysis that incorporated the CONUT score and the log BNP, showed that a higher CONUT score (P = 0.019) and higher log BNP (P = 0.009) were predictors of in-hospital death, and the median duration of hospital stay was 20 days.Our results demonstrate the usefulness of CONUT scores as predictors of short-term prognosis in hospitalized HF patients.

Cardiac Resynchronization Therapy in a Patient With a Failing Systemic Right Ventricle

Systemic right ventricular dysfunction is 1 of the late complications of the atrial switch operation for transposition of the great arteries. It has been reported that cardiac resynchronization therapy (CRT) for the failing systemic right ventricle (RV) improves symptoms and systolic function. However, patient selection for CRT in congenital heart disease is still challenging because the clinical standard for CRT in these patients is not established. We describe a case of successful implantation of a CRT device for a failing systemic RV aided by multimodality imaging and cardiac hemodynamic studies.

Optimal cut-off value of reverse remodeling to predict long-term outcome after cardiac resynchronization therapy in patients with ischemic cardiomyopathy

BACKGROUND Whether the optimal cut-off value of left ventricular (LV) reverse remodeling is different in patients with ischemic cardiomyopathy (ICM) vs. non-ischemic cardiomyopathy (NICM) is unclear. This study aimed to clarify this value in patients with ICM and NICM. METHODS AND RESULTS LV reverse remodeling was defined as a reduction in LV end-systolic volume (LVESV) at 6 months after cardiac resynchronization therapy (CRT). The clinical endpoint was the combination of cardiac death and first hospitalization for worsening heart failure. Ninety-one of 372 patients had ICM. Event-free survival rates did not differ between ICM and NICM groups (66.8% vs. 78.9%; p=0.12). Receiver operating characteristics analysis revealed a 9% reduction in ESV as the optimal cut-off value to predict the composite endpoint in patients with ICM and a 15% reduction in patients with NICM. Multivariate analysis revealed that reductions in ESV of ≥15% and ≥9% were independent predictors of the composite endpoint, as were left bundle branch block (LBBB) and B-type natriuretic peptide (BNP) at 6 months after CRT. In combination with LBBB and BNP, reduction in ESV ≥9% had a higher, but not significant, C-statistics value than ESV ≥15% (0.854, 95% CI 0.729-0.940 vs. 0.801, 95% CI 0.702-0.908, p=0.07). CONCLUSION The optimal cut-off value of a reduction in LVESV was lower in patients with ICM than in patients with NICM.

Value of 3-Dimensional Speckle Tracking Echocardiography in the Prediction of Microvascular Obstruction and Left Ventricular Remodeling in Patients With ST-Elevation Myocardial Infarction

BACKGROUND In patients with myocardial infarction (MI), microvascular obstruction (MVO) determined by cardiac magnetic resonance imaging (CMR) is associated with left ventricular (LV) remodeling and worse prognosis.Methods and Results:In 71 patients with ST-segment elevation MI (STEMI) treated by primary percutaneous coronary intervention (PCI), speckle tracking echocardiography (STE) and CMR were performed early after PCI. All patients underwent CMR at 6 months after hospital discharge to assess the occurrence of LV remodeling. The values of 3-dimensional (3D)-circumferential strain (CS), area change ratio (ACR), and 2-dimensional (2D)-CS were significantly different for the transmural extent of infarct, whereas the values of 3D- and 2D- longitudinal strain (LS) were not significantly different. In transmural infarct segments, the values of 3D-CS and ACR were significantly lower in segments with MVO than in those without MVO. At 6-month follow-up, LV remodeling was observed in 22 patients. In multivariable logistic regression models, global 3D-CS and ACR were significant determinants of LV remodeling rather than the number of MVO segments. CONCLUSIONS Regional 3D-CS and ACR reflected the transmural extent of infarct and were significantly associated with the presence of MVO. In addition, global 3D-CS and ACR were preferable to the extent of MVO in the prediction of LV remodeling.

Effect of Dipeptidyl Peptidase-4 Inhibitors on Cardiovascular Outcome and Cardiac Function in Patients With Diabetes and Heart Failure ― Insights From the Ibaraki Cardiac Assessment Study-Heart Failure (ICAS-HF) Registry ―

BACKGROUND Although experimental animal studies report many pleiotropic effects of dipeptidyl peptidase-4 inhibitors (DPP-4i), their prognostic value has not been demonstrated in clinical trials.Methods and Results:Among 838 prospectively enrolled heart failure (HF) patients hospitalized for acute decompensated HF, 79 treated with DPP-4i were compared with 79 propensity score-matched non-DPP-4i diabetes mellitus (DM) patients. The primary endpoint was all-cause mortality; the secondary endpoint was a composite of cardiovascular death and hospitalization. During follow-up (423±260 days), 8 patients (10.1%) in the DPP-4i group and 13 (16.5%) in the non-DPP-4i group died (log-rank, P=0.283). The DPP-4i group did not have a significantly higher rate of all-cause mortality (log-rank, P=0.283), or cardiovascular death or hospitalization (log-rank, P=0.425). In a subgroup analysis of HF with preserved ejection fraction (HFpEF; n=75), the DPP-4i group had a significantly better prognosis than the non-DPP-4i group regarding the primary endpoint (log-rank, P=0.021) and a tendency to have better prognosis regarding the secondary endpoint (log-rank, P=0.119). In patients with HF with reduced EF (n=83), DPP-4i did not result in better prognosis. CONCLUSIONS DPP-4i did not increase the risk of adverse clinical outcomes in patients with DM and HF. DPP-4i may be beneficial in HFpEF.

Three-dimensional echocardiography in the diagnosis of pacemaker lead perforation

Recently, due to increases in the number of cardiac device implantations, especially implantable cardioverter-defibrillators and cardiac resynchronization therapy, device complications have been experienced more frequently. Myocardial perforation of an implanted lead is one of the most severe complications. We report a case of ventricular lead perforation clearly visualized by 3-dimensional echocardiography, which was not identified by 2-dimensional echocardiography.