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The present case illustrates the diagnostic challenges in symptomatic patients with heart failure of unknown etiology. The patients were previously diagnosed with κ‐light chain amyloidosis without cardiac involvement. Echocardiography showed heart failure with mildly reduced ejection fraction but no signs of amyloidosis. Coronary angiogram showed normal arteries and 11C‐PIB positron emission tomography was negative for amyloid deposits. Exercise testing revealed severe heart failure and reduced coronary flow velocity reserve. Endomyocardial biopsies showed amyloid in the intramural coronary arteries without interstitial amyloid deposits. Hence, the patient was diagnosed with microvascular dysfunction‐induced heart failure due to vessel wall amyloidosis.  相似文献   
3.

Introduction

Magnetic resonance imaging using the delayed contrast-enhanced (DE-MRI) method can be used for characterizing and quantifying myocardial infarction (MI). Electrocardiogram (ECG) score after the acute phase of MI can be used to estimate the portion of left ventricular myocardium that has infracted. There are no comparison of serial changes on ECG and DE-MRI measuring infarct size.

Aim

The general aim of this study was to describe the acute, healing, and chronic phases of the changes in infarct size estimated by the ECG and DE-MRI. The specific aim was to compare estimates of the Selvester QRS scoring system and DE-MRI to identify the difference between the extent of left ventricle occupied by infarction in the acute and chronic phases.

Methods

In 31 patients (26 men, age 56 ± 9) with reperfused ST-elevation MI (11 anterior, 20 inferior), standard 12-lead ECG and DE-MRI were taken from 1 to 2 days (acute), 1 month (healing), and 6 months (chronic) after the MI. Selvester QRS scoring was used to estimate the infarct size from the ECG.

Results

The correlation values between infarct size measured by DE-MRI and QRS scoring range from 0.33 to 0.43 higher for anterior than inferior infarcts. The infarct size estimated by QRS scoring was larger (about 5% of the left ventricle) than infarct size by DE-MRI acute and 1 month, but at 6 months, there was no difference. In about half of the patients, the QRS score agreed with DE-MRI in change of infarct size from acute to 6 months.

Conclusion

In conclusion, the Selvester QRS scoring system is in half of the patients with reperfused first time MI in good accordance with DE-MRI in identifying a decrease or no change in the extent of left ventricle occupied by infarction in the acute and chronic phases.  相似文献   
4.
The aim of the study was to evaluate the long‐term influence of repeated acute cellular rejections on left ventricular longitudinal deformation in heart transplantation (HTX) patients. One hundred and seventy‐eight HTX patients were included in the study. Rejections were classified according to the International Society of Heart and Lung Transplantation (ISHLT) classification (0R–3R). Patients were divided into three groups according to rejection scores (RSs). Group 1: <50% of biopsies with 1R rejection and no ≥2R rejections; Group 2: ≥50% of biopsies with 1R rejection or one biopsy with ≥2R rejection; Group 3: ≥Two biopsies with ≥2R rejections. All patients had a comprehensive echocardiographic examination and coronary angiography. We found significantly decreasing global longitudinal strain (GLS) comparing to rejection groups (GLS group 1: ?16.8 ± 2.4 (%); GLS group 2: ?15.9 ± 3.3 (%); GLS group 3: ?14.5 ± 2.9 (%), P = 0.0003). After excluding patients with LVEF < 50% or vasculopathy, GLS was still significantly reduced according to RS groups (P = 0.0096). Total number of 1R and 2R rejections correlated significant to GLS in a linear regression model. In contrast, we found fractional shortening and LVEF to be unaffected by repeated rejections. In conclusion, repeated cardiac rejections lead to impaired graft function as detected by decreasing magnitude of GLS. In contrast, traditional systolic graft function surveillance by LVEF did not correlate to rejection burden.  相似文献   
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This study aimed to assess clinical, functional, and hemodynamic characteristics of heart‐transplanted (HTX) patients during exercise. We performed comprehensive echocardiographic graft function assessment during invasive hemodynamic semi‐supine exercise test in 57 HTX patients. According to hemodynamics findings, patients were divided into Group A: normal left ventricular (LV) filling pressure (FP): pulmonary capillary wedge pressure (PCWP) <15 mmHg at rest and <25 mmHg at peak exercise, and Group B: elevated LV‐FP: PCWP ≥15 mmHg at rest or ≥25 mmHg at peak exercise. Thirty‐one patients (54%) had normal LV‐FP and 26 patients (46%) had elevated LV‐FP. The latter had higher cumulative rejection burden (P < 0.01) and were more symptomatic (NYHA class >1) (P < 0.05), and cardiac allograft vasculopathy (CAV) was more prevalent (P < 0.05). With exercise, the changes in both left‐ and right‐sided filling pressures were significantly increased, whereas LV longitudinal myocardial deformation was lower (P < 0.05) in patients with elevated LV‐FP than in patients with normal LV‐FP. No between‐group difference was observed for cardiac index or LV ejection fraction (LVEF) during exercise. In conclusion, elevated LV‐FP can be demonstrated in approximately 50% of HTX patients. Patients with elevated LV‐FP have impaired myocardial deformation capacity, higher prevalence of CAV, and higher rejection burden, and were more symptomatic. Exercise test with the assessment of longitudinal myocardial deformation should be considered in routine surveillance of HTX patients as a marker of restrictive filling (ClinicalTrials.gov Identifier: NCT02077764).  相似文献   
8.
Radiation therapy may affect several important parameters in the tumor microenvironment and thereby influence the accumulation of liposomes by the enhanced permeability and retention (EPR)-effect. Here we investigate the effect of single dose radiation therapy on liposome tumor accumulation by PET/CT imaging using radiolabeled liposomes. Head and neck cancer xenografts (FaDu) and syngenic colorectal (CT26) cancer models were investigated. Radiotherapy displayed opposite effects in the two models. FaDu tumors displayed increased mean accumulation of liposomes for radiation doses up to 10 Gy, whereas CT26 tumors displayed a tendency for decreased accumulation. Tumor hypoxia was found negatively correlated to microregional distribution of liposomes. However, liposome distribution in relation to hypoxia was improved at lower radiation doses. The study reveals that the heterogeneity in liposome tumor accumulation between tumors and different radiation protocols are important factors that need to be taken into consideration to achieve optimal effect of liposome based radio-sensitizer therapy.  相似文献   
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Background and purpose

We aimed to study the prevalence of acute cardiac disorders in patients with suspected ST-segment elevation myocardial infarction (STEMI) and non-significant coronary artery disease (CAD).

Methods

From January to October 2012 we consecutively included patients admitted with suspected STEMI and non-significant CAD (coronary artery stenosis diameter < 50%). Patients were diagnosed with acute cardiac disorder in the presence of elevated cardiac biomarkers (troponin T > 50 ng/l or creatine kinase MB > 4 μg/l) or dynamic ECG changes (ST-segment changes or T-wave inversion).

Results

Of the 871 patients admitted with suspected STEMI, 11% (n = 95) had non-significant CAD. Of these, 67% (n = 64) had elevated cardiac biomarkers or dynamic ECG changes and were accordingly diagnosed with acute cardiac disorders. In the remaining 33% (n = 31) of patients, cardiac biomarkers were normal and ECG changes remained stationary.

Conclusions

Acute cardiac disorders were diagnosed in two thirds of patients with suspected STEMI and non-significant CAD.  相似文献   
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