Genetic and antigenic characterisation of influenza A(H3N2) viruses isolated in Yokohama during the 2016/17 and 2017/18 influenza seasons.

BACKGROUND: Influenza A(H3N2) virus rapidly evolves to evade human immune responses, resulting in changes in the antigenicity of haemagglutinin (HA). Therefore, continuous genetic and antigenic analyses of A(H3N2) virus are necessary to detect antigenic mutants as quickly as possible. AIM: We attempted to phylogenetically and antigenically capture the epidemic trend of A(H3N2) virus infection in Yokohama, Japan during the 2016/17 and 2017/18 influenza seasons. METHODS: We determined the HA sequences of A(H3N2) viruses detected in Yokohama, Japan during the 2016/17 and 2017/18 influenza seasons to identify amino acid substitutions and the loss or gain of potential N-glycosylation sites in HA, both of which potentially affect the antigenicity of HA. We also examined the antigenicity of isolates using ferret antisera obtained from experimentally infected ferrets. RESULTS: Influenza A(H3N2) viruses belonging to six clades (clades 3C.2A1, 3C.2A1a, 3C.2A1b, 3C.2A2, 3C.2A3 and 3C.2A4) were detected during the 2016/17 influenza season, whereas viruses belonging to two clades (clades 3C.2A1b and 3C.2A2) dominated during the 2017/18 influenza season. The isolates in clades 3C.2A1a and 3C.2A3 lost one N-linked glycosylation site in HA relative to other clades. Antigenic analysis revealed antigenic differences among clades, especially clade 3C.2A2 and 3C.2A4 viruses, which showed distinct antigenic differences from each other and from other clades in the antigenic map. CONCLUSION: Multiple clades, some of which differed antigenically from others, co-circulated in Yokohama, Japan during the 2016/17 and 2017/18 influenza seasons

Pump failure death and sudden cardiac death in patients with cardiac dysfunction: A search for prognostic predictive factors—A long-term follow-up study

SummaryBackgroundThere have been few reports that have analyzed the predictive factors for heart failure death, which is sub-divided into pump failure death and sudden cardiac death, in the long term.Methods and resultsWe followed 186 consecutive patients with myocardial infarction (MI) and 115 consecutive patients with non-ischemic heart failure (NIHF) during 73±3 months. In the MI group, 26 died from pump failure and 12 died from sudden cardiac death. In the NIHF group, 21 died from pump failure and 9 died from sudden cardiac death. Multivariate analysis revealed that the log B-type natriuretic peptide (BNP) was an independent predictor for pump failure death in both groups. In the MI group, the estimated glomerular filtration rate (eGFR) was an independent predictor for sudden cardiac death. Kaplan–Meier analysis revealed that a high BNP level was a risk factor for pump failure death in either MI or NIHF patients. On the other hand, the sudden cardiac death rate was significantly higher in the MI patients with low eGFR than in those with high eGFR.ConclusionsThe plasma BNP level is an independent predictor for pump failure death in both MI and NIHF patients. The eGFR is an independent predictor for sudden cardiac death in MI patients

Correlation Between Cardiac Images, Biomarkers, and Amyloid Load in Wild‐Type Transthyretin Amyloid Cardiomyopathy

Background Several imaging parameters and biomarkers provide diagnostic and prognostic information for wild‐type transthyretin amyloid cardiomyopathy. However, the relevance of these parameters and their association with cardiac amyloid load requires further substantiation. We aimed to elucidate the association of imaging parameters obtained using 99mTc‐labeled pyrophosphate scintigraphy, cardiovascular magnetic resonance imaging, global longitudinal strain (GLS), and cardiac biomarkers with cardiac amyloid load in patients with wild‐type transthyretin amyloid cardiomyopathy. Methods and Results Eighty‐eight patients with wild‐type transthyretin amyloid cardiomyopathy who underwent 99mTc‐labeled pyrophosphate scintigraphy and cardiovascular magnetic resonance were retrospectively evaluated. Quantitative cardiac amyloid load was obtained from 61 patients after myocardial biopsy. Correlations were assessed using Pearson’s correlation coefficient applied to medical record data. The mean heart to contralateral ratio, native T1, extracellular volume, and GLS were 1.91±0.36, 1419.4±56.4 ms, 56.5±13.6%, and −9.4±2.5%, respectively. Median high‐sensitivity cardiac troponin T (hs‐cTnT) and BNP (B‐type natriuretic peptide) levels were 0.0478 (0.0334‐0.0691) ng/mL and 213.8 (125.8–392.7) pg/mL, respectively. The mean cardiac amyloid load was 22.9±15.0%. The heart to contralateral ratio correlated significantly with native T1 (r=0.397), extracellular volume (r=0.477), GLS (r=0.363), cardiac amyloid load (r=0.379), and Ln (hs‐cTnT) (r=0.247). Further, cardiac amyloid load correlated significantly with native T1 (r=0.509), extracellular volume (r=0.310), GLS (r=0.446), and Ln (hs‐cTnT) (r=0.354). Compared with BNP, hs‐cTnT levels better correlated with several imaging parameters and cardiac amyloid load. Conclusions Increased cardiac amyloid load correlated with increased 99mTc‐labeled pyrophosphate positivity, native T1, extracellular volume, and hs‐cTnT levels, and an impaired GLS, suggesting that imaging parameters and cardiac biomarkers may reflect histological and functional changes attributable to amyloid deposition in the myocardium

Usefulness of automatic assessment for longitudinal strain to diagnose wild-type transthyretin amyloid cardiomyopathy

Background: Left ventricular (LV) apical sparing by transthoracic echocardiography (TTE) has not been widely accepted to diagnose transthyretin amyloid cardiomyopathy (ATTR-CM), because it is time consuming and requires a level of expertise. We hypothesized that automatic assessment may be the solution for these problems. Methods-and-Results: We enrolled 63 patients aged ≥70 years who underwent 99mTc-labeled pyrophosphate (99mTc-PYP) scintigraphy on suspicion of ATTR-CM and performed TTE by EPIQ7G, and had enough information for two-dimensional speckle tracking echocardiography at Kumamoto University Hospital from January 2016 to December 2019. LV apical sparing was described as a high relative apical longitudinal strain (LS) index (RapLSI). Measurement of LS was repeated using the same apical images with three different measurement packages as follows: (1) full-automatic assessment, (2) semi-automatic assessment, and (3) manual assessment. The calculation time for full-automatic assessment (14.7 ± 1.4 sec/patient) and semi-automatic assessment (66.7 ± 14.4 sec/patient) were significantly shorter than that for manual assessment (171.2 ± 59.7 sec/patient) (p < 0.01 for both). Receiver operating characteristic curve analysis showed that the area under curve of the RapLSI evaluated by full-automatic assessment for predicting ATTR-CM was 0.70 (best cut-off point; 1.14 [sensitivity 63%, specificity 81%]), by semi-automatic assessment was 0.85 (best cut-off point; 1.00 [sensitivity, 66%; specificity, 100%]) and by manual assessment was 0.83 (best cut-off point; 0.97 [sensitivity, 72%; specificity, 97%]). Conclusion: There was no significant difference between the diagnostic accuracy of RapLSI estimated by semi-automatic assessment and that estimated by manual assessment. Semi-automatically assessed RapLSI is useful to diagnose ATTR-CM in terms of rapidity and diagnostic accuracy