Usefulness of right ventricular tissue Doppler imaging for diagnosis of right ventricular myocardial infarction

Background

Right ventricular myocardial infarction (RVMI) is a complication of acute inferior myocardial infarction and sometimes causes severe hemodynamic disturbance. It is therefore important to promptly detect RVMI and assess the severity of right ventricular (RV) dysfunction. Tissue Doppler imaging (TDI) is a useful method to assess left ventricular function and RV function. In this study, we investigated the possibility of diagnosing RVMI using tricuspid annular velocity determined by TDI.

Methods

Thirty consecutive patients with first acute inferior myocardial infarction were studied. The diagnosis of RVMI was based on an ST-segment elevation of at least 0.1 mV in lead V4R. The patients were classified into 12 patients with RVMI (the RVMI group) and 18 patients without RVMI (non-RVMI group). All patients underwent two-dimensional echocardiography, pulsed Doppler and TDI, and coronary angiography within 48 h after onset of myocardial infarction. Tricuspid inflow velocity was recorded by pulsed Doppler and early diastolic tricuspid inflow velocity (TVE) was measured. Peak early diastolic velocity of the tricuspid annulus (TVe’) at the RV free wall was recorded using TDI. The ratio of TVE to TVe’ (TVE/TVe’) was calculated.

Results

TVe’ was significantly lower in the RVMI group compared to that in the non-RVMI group (5.9 ± 1.3 vs. 9.1 ± 3.1; p = 0.0025). On the basis of a TVe’ cutoff value of less than 8.3 cm/s, RVMI was diagnosed with 100 % sensitivity and 61 % specificity.

Conclusions

The early diastolic tricuspid annular velocity determined by TDI is a noninvasive and sensitive index for diagnosing RVMI.     

Introduction of the targeted alpha therapy (with Radium-223) into clinical practice in Japan: learnings and implementation

Annals of Nuclear Medicine - Radium-223 dichloride (Ra-223) is the first targeted alpha therapy approved for the treatment of patients with castration-resistant prostate cancer (CRPC) with bone...     

Niemann-Pick C1-like 1 overexpression facilitates ezetimibe-sensitive cholesterol and beta-sitosterol uptake in CaCo-2 cells

Previous in vivo studies including those with knockout mice suggested that Niemann-Pick C1-like 1 (NPC1L1) plays an essential role in the intestinal absorption of cholesterol. To characterize the mechanism of cholesterol uptake mediated by NPC1L1, an in vitro system reflecting the function of this transporter needs to be established. In the present study, we constructed NPC1L1 overexpressing CaCo-2 cells as an in vitro model and characterized the transport properties of NPC1L1. Immunohistochemical staining revealed that CaCo-2 cells express NPC1L1 on the apical membrane. It was also demonstrated that the uptakes of both cholesterol and beta-sitosterol are increased by NPC1L1 overexpression. In addition, the uptake of cholesterol was increased in a dose-dependent manner by an increase in the content of taurocholate in micelles, whereas micellar phosphatidylcholine showed a negative correlation with cholesterol uptake. Furthermore, it was confirmed that sterol uptake increased by NPC1L1 overexpression was inhibited by ezetimibe. We could thus establish an in vitro intestinal model to study the mechanism of NPC1L1-dependent sterol uptake and to screen drug candidates whose target is NPC1L1.     

Combination of pancreas volume and HbA1c level predicts islet yield in patients undergoing total pancreatectomy and islet autotransplantation

Islet yield is an important predictor of acceptable glucose control after total pancreatectomy with islet autotransplantation (TP-IAT). We assessed if pancreas volume calculated with preoperative MRI could assess islet yield and postoperative outcomes. We reviewed dynamic MRI studies from 154 adult TP-IAT patients (2009-2016), and associations between calculated volumes and digest islet equivalents (IEQs) were tested. In multivariate regression analysis, pancreas volume (P < .001) and preoperative HbA1c levels (P = .009) were independently associated with digest IEQs. The IEQ prediction formula was calculated according to each preoperative HbA1c level, (a) pancreas volume × 5800 for HbA1c ≥ 6.5, (b) pancreas volume × 10 000 for HbA1c ≥5.7/<6.5 and (iii) pancreas volume × 11 400 for HbA1c < 5.7. The formula was internally validated with 28 TP-IAT patients between 2017 and 2018 (r² = .657 and r² = .710 when restricted to 24 patients without prior pancreatectomy). An estimated IEQs/Body Weight (kg) ≥3700 predicted HbA1c ≤6.5 and insulin independence at 1 year after TP-IAT with 77% and 88% sensitivity and 55% and 43% specificity, respectively. The combination of pancreas volume and preoperative HbA1c levels may be useful to estimate islet yield. Estimated IEQs were reasonably sensitive to predict acceptable glucose control at 1 year.     

Diverse p53 gene aberration in hepatocellular carcinoma detected by dual-color fluorescence in situ hybridization

BACKGROUND AND AIM: In order to evaluate loss of the p53 gene more precisely, we performed dual-color fluorescence in situ hybridization (dual-color FISH) for chromosome 17 and p53 gene together with DNA polymorphism analysis of the p53 gene in hepatocellular carcinoma (HCC). METHODS: Dual-color FISH using probes specific for the centromere of chromosome 17 and the p53 gene was performed for 41 HCC and DNA polymorphism analysis was also performed for them. RESULTS: Of the 34 HCC tested by dual-color FISH, 20 had loss of at least one p53 gene (58.8%). In contrast, of the 32 HCC tested by DNA polymorphism analysis, 23 gave informative results, among which only eight had loss of heterozygosity (LOH) of the p53 gene (34.8%). Notably, among 14 cases positive for loss of the p53 gene by dual-color FISH, seven cases were negative for LOH of the p53 gene. Moreover, dual-color FISH revealed that the percentage of cells that lost at least one p53 gene increased as the HCC became less differentiated (P < 0.01), whereas LOH did not reveal any such correlation. CONCLUSIONS: These data suggest that loss of the p53 gene was present in a considerable number of HCC, and diversity of the p53 gene aberration increases with progression of HCC. Dual-color FISH is an effective method for detection of p53 gene aberration, and it can provide new insight into oncogenesis in HCC.     

Effectiveness of combined anticoagulant therapy for extending portal vein thrombosis in Crohn's disease

PURPOSE: Portal vein thrombosis is a rare complication of Crohn's disease, and its precise cause and appropriate treatment are not known. We describe a patient with extending portal vein thrombosis in Crohn's disease who was successfully treated with combined anticoagulant therapy. METHOD: Urokinase and tissue plasminogen activator were administered from a catheter inserted into the superior mesenteric artery, and heparin and a serine protease inhibitor also were given intravenously. RESULTS: On admission, thromboembolic occlusion was observed throughout the entire portal venous system in association with massive ascites and remarkable intestinal edema. After administration of combined anticoagulant therapy, thrombus rapidly decreased in size, and color Doppler ultrasonography showed a gradual increase in portal venous flow. The patient had no recurrence of symptoms while receiving warfarin after resolution of thrombus. CONCLUSION: This case report suggests that combined anticoagulant therapy is effective for patients with severe portal vein thrombosis in Crohn's disease and that color Doppler ultrasonography is useful for evaluation of portal venous flow.     

Characterization of complement C3, C4, and factor B molecules in human bile

We performed molecular analysis of complement components (C3, C4, and factor B) in human bile by sodium dodecyl sulfate-polyarylamide gel electrophoresis (SDS-PAGE) and immunoblotting. Complement C3 was detected as a molecule composed of a 115-kDa α-chain linked to a 70-kDa β-chain by disulfide bonds, and C3 levels ranged from 45 to 650μg/ml (n=15). C4 was detected as a triple chain (98-kDa α-chain, 73-kDa β-chain, and 33-kDa γ-chain) molecule linked by disulfide bonds, and C4 levels ranged from 2.5 to 60μg/ml. Factor B, a component of the alternative pathway, was also detected, as an intact form. Factor B levels ranged from 0.3 to 8.0μg/ml. The sizes and subunit structures of complement components in human bile were compatible with those reported in human serum. The results of a hemolytic assay indicated that complement molecules in human bile were functionally active. These molecules may participate in local immune and inflammatory responses in the biliary tract.     

High-density activation mapping of fractionated electrograms in the atria of patients with paroxysmal atrial fibrillation

BACKGROUND: Areas of complex fractionated atrial electrograms (CFAEs) have been implicated in the atrial substrate of atrial fibrillation (AF). The mechanisms underlying CFAE in humans are not well investigated. OBJECTIVES: The purpose of this study was to investigate the regional activation pattern associated with CFAE using a high-density contact mapping catheter. METHODS: Twenty patients with paroxysmal AF were mapped using a high-density multielectrode catheter. CFAE were mapped at 10 different sites (left atrium [LA]: inferior, posterior, roof, septum, anterior, lateral; right atrium [RA]: anterior, lateral, posterior, septum). Local atrial fibrillation cycle length (AFCL) was measured immediately before and after the occurrence of CFAE, and the longest electrogram duration (CFAEmax) was assessed. RESULTS: Longer electrogram durations were recorded in the LA compared with the RA (CFAEmax 118 +/- 21 ms vs 104 +/- 23 ms, P = .001). AFCL significantly shortened before the occurrence of CFAEmax compared with baseline (LA: 174 +/- 32 ms vs 186 +/- 32 ms, P = .0001; RA: 177 +/- 31 ms vs 188 +/- 31 ms, P = .0001) and returned to baseline afterwards. AFCL shortened by >or=10 ms in 91% of mapped sites. Two different local activation patterns were associated with occurrence of CFAEmax: a nearly simultaneous activation in all spines in 84% indicating passive activation, and a nonsimultaneous activation sequence suggesting local complex activation or reentry. CONCLUSION: Fractionated atrial electrograms during AF demonstrate dynamic changes that are dependent on regional AFCL. Shortening of AFCL precedes the development of CFAE; thus, cycle length is a major determinant of fractionation during AF. High-density mapping in AF may help to differentiate passive activation of CFAE from CFAE associated with an active component of the AF process.     

CHA2DS2-VASc score is a useful-predictor of not prognosis but coronary-arteriosclerosis in chronic atrial-fibrillation compared with CHADS2 score: A two-center study of 320-slice CT,part 2

Background

The aim of this study is to predict the risk of coronary-arteriosclerosis and prognosis in subjects with chronic-atrial-fibrillation (CAF) using the CHADS2 and CHA2DS2-VASc scores by 320-slice-CT and invasive-coronary-angiography (ICA) in a two-center-study.

Methods

53 CAF subjects who underwent 320-slice-CT and ICA within 6-months (43 male; 69 ± 9 years; CHADS2 score 2.2 ± 1.3; CHA2DS2-VASc score 3.5 ± 1.6) in the two-institutes were analyzed. CT and ICA data were transferred to the analysis-center and were analyzed by cardiologists.

Results

Agatston-calcium-score and frequencies of the presence of various-kinds of plaques and > 50% and > 75% coronary artery stenosis were significantly higher in the subjects with CHA2DS2-VASc score ≥ 3 compared with those with score < 3. However there were no-significant differences in the Agatston-calcium-score and frequencies of the presence of various-kinds of plaques and > 50% and > 75% coronary artery stenosis evaluated by 320-slice CT between the subjects with CHADS2 score ≥ 2 and < 2. Frequency of > 50% coronary artery stenosis by ICA was significantly higher in the subjects with CHA2DS2-VASc score ≥ 3 compared with those with score < 3. However, there were no-significant differences in the frequencies of > 50% and > 75% coronary artery stenosis by ICA between the subjects with CHADS2 score ≥ 2 and < 2. During a mean of 15.9 months, composite rate of cardiac death and heart failure did not differ between subjects with CHADS2 score ≥ 2 and score < 2 and between subjects with CHA2DS2-VASc score ≥ 3 and score < 3.

Conclusions

The CHA2DS2-VASc score is a useful predictor of not prognosis but coronary-arteriosclerosis in subjects with CAF compared with CHADS2 score in this two-center-study.