Secondary sarcopenia assessed by computed tomography can predict hospitalization for heart failure in adults with Fontan circulation.

BACKGROUND: Sarcopenia is one of the important predictors of heart failure (HF) in patients with cardiac problems. Skeletal muscle pump is important to maintain Fontan circulation. We aimed to quantify the volume of the psoas major muscle (PMM) and investigate whether it is relevant to HF hospitalization in adults with Fontan circulation. METHODS: A total of 154 adults with Fontan circulation, and 30 age-matched adults were studied retrospectively. We identified secondary sarcopenia by measuring the PMM volume, using non-contrast abdominal computed tomography. RESULTS: PMM indexed volume in Fontan patients was lower than controls (206.4+/-18.0 cc/m2 vs 288.0+/-61.1 cc/m2, p < 0.0001). In Fontan men, PMM indexed volume correlated with New York Heart Association functional class (NYHA FC). PMM indexed volume in Fontan women correlated with age, NYHA FC, and serum creatinine. Using a multivariate Cox hazards analysis, NYHA FC ≧3 was an important predictor of hospitalization due to HF in Fontan men. In Fontan women, NYHA FC ≧3, brain natriuretic peptide, PMM indexed volume, and protein losing enteropathy were important predictions of hospitalization due to HF. Among all Fontan patients, those with low PMM volumes had a poorer prognosis in HF [log rank p = 0.012 (men) and 0.0009 (women)]. CONCLUSIONS: PMM volume reduction has an adjunctive prediction of HF hospitalization in adults with Fontan circulation, particularly in Fontan females. Secondary sarcopenia may have a negative impact on the prognosis of HF in this population. The assessment of skeletal muscle mass also may be a comprehensive screening tool for multi-organ dysfunction in Fontan circulation.

Clinical impact of cardiac computed tomography derived three-dimensional strain for adult congenital heart disease: a pilot study.

To assess ventricular function and dyssynchrony using three-dimensional (3D) computed tomography (CT) strain in adult congenital heart disease (ACHD). We prospectively analyzed a multiphase cardiac CT data set for 22 adult patients with CHD, including 8 patients with congenital systemic right ventricle (RV) and 14 patients with repaired Tetralogy of Fallot (TOF). Eight patients had a cardiac pacemaker. Volume of Interest was drawn on a multiplanar reconstruction of the ventricle with strain overlay using a 3D-strain algorithm. Ventricular strain, inter- and intraventricular dyssynchrony, and right ventricle outflow tract (RVOT)-apex dyssynchrony were calculated. RVOT-apex dyssynchrony by ventriculography was also compared in 15 patients. Pulmonary ventricular strain, systemic ventricular strain, and septal wall strain were lower in ACHD patients than in the controls, and lower in the ACHD with pacing group than without pacing group as well. Maximum interventricular time difference and intraventricular time difference were longer than in ACHD than in the controls, and longer in the ACHD with pacing group than without pacing group as well. RVOT-apex delay was significantly longer in patients with a pacemaker than in those without a pacemaker (118.1 ± 31.9 ms vs. 76.1 ± 36.2 ms, p = 0.03). RVOT delay determined by 3D CT strain significantly correlated with that determined by ventriculography (Pearson r = 0.55, p = 0.03). 3D CT strain can detect reduced biventricular contraction and inter- and intraventricular and RVOT-apex mechanical dyssynchrony can be assessed in patients with ACHD.

Feasible scan timing for 320-row coronary CT angiography generated by the time to peak in the ascending aorta.

PURPOSE: A 320-row CT scanner can briefly scan the entire heart. Therefore, the feasible scan timing is required. The aim of this study was to propose a refined method for feasible scan timing for coronary CT angiography (CCTA) using a time-density curve of the ascending aorta (AAo). METHODS: One-hundred and twenty-nine patients were prospectively enrolled. All patients were performed test-bolus method. For the initial 65 patients, the scan timing was determined as a 3.0 s delay at the peak time in the AAo, which was defined as the conventional protocol (COV-P). For the next 64 patients, a scan timing of 1.0, 3.0, or 5.0 s delay was determined according to the interval from the contrast media arrival to peak time in the AAo, which was defined as the arrival to peak protocol (AP-P). The optimal scan timing was identified by the measurement of CT number in the left atrium, left ventricle, AAo, and descending aorta. The coronary enhancement and heterogeneity were compared between the two protocols. RESULTS: The optimal scan timing was significantly higher in the AP-P than in the COV-P (85.9% vs. 61.5%, p = 0.0017). The CT number in the left circumflex artery (LCX) was significantly higher in the AP-P than the COV-P (344.5 Hounsfield units vs. 316.3 Hounsfield units, p = 0.0484). The heterogeneous index of the LCX was significantly greater for the COV-P than the AP-P (-36.8 vs. -25.8, p = 0.0028). CONCLUSIONS: The AP-P can be used to determine the optimal scan timing for CCTA and contributes to stable coronary enhancement.

Improved Visualization of Middle Ear Cholesteatoma with Computed Diffusion-weighted Imaging.

Computed DWI (cDWI) is a mathematical technique that calculates arbitrary higher b value images from at least two different lower b values. In addition, the removal of high intensity noise with image processing on cDWI could improve cholesteatoma-background contrast-to-noise ratio (CNR). In the present study, noise reduction was performed by the cut-off values of apparent diffusion coefficient (ADC) less than 0 and 0.4 × 10-3 s/mm2. The cholesteatoma to non-cholesteatoma CNR was increased using a noise reduction algorithm for clinical setting.

Prediction of Fontan-Associated Liver Disease Using a Novel Cine Magnetic Resonance Imaging "Vortex Flow Map" in the Right Atrium.

BACKGROUND: Long-term hepatic dysfunction is an increasingly recognized complication of the Fontan operation for univentricular hearts. The purpose of this study was to determine whether Fontan-associated liver disease (FALD) could be predicted by flow dynamics in the right atrium (RA) of Fontan circulation.Methods and Results:Cardiac MRI and the serum levels of total bilirubin (TBil) and hyaluronic acid (HA) were analyzed in 36 patients who underwent an atriopulmonary connection type of Fontan operation. The mean follow-up period was 53 months. Three views (axial, coronal, and sagittal) of the cine images were scanned for the maximum cross-section of the RA obtained with1.5-Tesla scanner. We developed a "vortex flow map" to demonstrate the ratio of the circumferential voxel movement in each phase to the total movement throughout a cardiac cycle towards the center of the RA. The maximum ratio was used as the magnitude of vortex flow (MVF%) in the 3 views of the RA cine imaging. Patients with coronal MVF ≥13.6% had significantly lower free rates of TBil ≥1.8 mg/dL than those with coronal MVF <13.6% (log-rank value=4.50; P<0.05; hazard ratio=4.54). Patients with sagittal MVF ≥14.0% had significantly lower free rates of HA ≥50 ng/mL than those with coronal MVF <14.0% (log-rank value=4.40; P<0.05; hazard ratio=4.12). CONCLUSIONS: A reduced vortex flow in the RA during the late phase of the Fontan operation was associated with the development of FALD. MVF can be used as an imaging biomarker to predict FALD.

Dynamic flow imaging using 320-detector row CT and motion coherence analysis in coronary aneurysms associated with Kawasaki disease.

Introduction We propose a new dynamic flow imaging using 320-detector row CT, and investigate the assessment of coronary flow in aneurysms of Kawasaki disease in adulthood. METHODS: Six patients with Kawasaki disease and coronary aneurysms associated (26.7 years old) and six controls were enrolled. Dynamic coronary CT angiography with 320-row CT was continuously performed at mid-diastole throughout 15-25 cardiac cycles with prospective Electrocardiogram gating after injection of contrast media. Dynamic data sets of 15-25 cycles were computed into 90-100 data sets by motion coherence image processing. Next, time-density curves for coronary arteries were calculated for all the phases. On the basis of the maximum slope method, coronary flow index was defined as the ratio of the maximum upslope of the attenuation of coronary arteries to the upslope of the attenuation of ascending aorta on the time-density curves. Coronary flow indexes for the proximal and distal sites of coronary arteries and intra-aneurysm were measured.

Vortex Flow in the Right Atrium Surrogates Supraventricular Arrhythmia and Thrombus After Atriopulmonary Connection-Type Fontan Operation: Vortex Flow Analysis Using Conventional Cine Magnetic Resonance Imaging.

We developed a novel imaging technique, designated as vortex flow (VF) mapping, which presents a vortex flow visually on conventional two-dimensional (2D) cine MRI. Using it, we assessed circumferential VF patterns and influences on RA thrombus and supraventricular tachycardia (SVT) in AP connection-type Fontan circulation. Retrospectively, we enrolled 27 consecutive patients (25.1 ± 9.2 years) and 7 age-matched controls who underwent cardiac MRI. Conventional cine images acquired using a 1.5-Tesla scanner were scanned for axial and coronal cross section of the RA. We developed "vortex flow mapping" to demonstrate the ratio of the circumferential voxel movement at each phase to the total movement throughout a cardiac cycle towards the RA center. The maximum ratio was used as a magnitude of vortex flow (MVF%) in RA cine imaging. We also measured percentages of strong and weak VF areas (VFA%). Furthermore, in 10 out of 27, we compared VF between previous CMR (3.8 ± 1.5 years ago) and latest CMR. Of the patients, 15 had cardiovascular complications (Group A); 12 did not (Group B). A transaxial image showed that strong VFA% in Group A was significantly smaller than that in Group B or controls. A coronal view revealed that strong VFA% was also smaller, and weak VFA% was larger in Group A than in Group B or controls (P < 0.05, and P < 0.05). Maximum MVF% in Group A was significantly smaller than in other groups (P < 0.001). Univariate logistic analyses revealed weak VFA% on a coronal image, and serum total bilirubin level as factors affecting cardiovascular complications (Odds ratio 1.14 and 66.1, 95% CI 1.004-1.30 and 1.59-2755.6, P values < 0.05 and < 0.05, respectively). Compared to the previous CMR, smaller maximum VMF%, smaller strong VFA%, and larger weak VFA% were identified in the latest CMR. Circumferentially weak VFA% on a coronal image can be one surrogate marker of SVT and thrombus in AP connection-type Fontan circulation. This simple VF assessment is clinically useful to detect blood stagnation.

Optimal scan timing for artery-vein separation at whole-brain CT angiography using a 320-row MDCT volume scanner.

OBJECTIVE: A 320-row multidetector CT (MDCT) is expected for a good artery-vein separation in terms of temporal resolution. However, a shortened scan duration may lead to insufficient vascular enhancement. We assessed the optimal scan timing for the artery-vein separation at whole-brain CT angiography (CTA) when bolus tracking was used at 320-row MDCT. METHODS: We analyzed 60 patients, who underwent whole-brain four-dimensional CTA. Difference in CT attenuation between the internal carotid artery (ICA) and the superior sagittal sinus (Datt) was calculated in each phase. Using a visual evaluation score for the depiction of arteries and veins, we calculated the difference between the mean score for the intracranial arteries and the mean score for the veins (Dscore). We assessed the time at which the maximum Datt and Dscore were simultaneously observed. RESULTS: The maximum Datt was observed at 6.0 s and 8.0 s in the arterial-dominant phase and at 16.0 s and 18.0 s in the venous-dominant phase after the contrast media arrival time at the ICA (Taa). The maximum Dscore was observed at 6.0 s and 8.0 s in the arterial-dominant phase and at 16.0 s in the venous-dominant phase after the Taa. There were no statistically significant differences in Datt (p = 0.375) or Dscore (p = 0.139) between these scan timings. CONCLUSION: The optimal scan timing for artery-vein separation at whole-brain CTA was 6.0 s or 8.0 s for the arteries and 16.0 s for the veins after the Taa. Advances in knowledge: Optimal scan timing allowed us to visualize intracranial arteries or veins with minimal superimposition.

Quantification of coronary flow using dynamic angiography with 320-detector row CT and motion coherence image processing: Detection of ischemia for intermediate coronary stenosis.

OBJECTIVES: Anatomical coronary stenosis is not always indicative of functional stenosis, particularly for intermediate coronary lesions. The purpose of this study is to propose a new method for quantifying coronary flow using dynamic CT angiography for the whole heart (heart-DCT) and investigate its ability for detecting ischemia from intermediate coronary stenosis. METHODS: Participants comprised 36 patients with coronary artery disease who underwent heart-DCT using 320-detector CT with tube voltage of 80kV and myocardial perfusion scintigraphy (MPS). Heart-DCT was continuously performed at mid-diastole throughout 15-25 cardiac cycles with prospective ECG-gating after bolus injection of contrast media (12-24ml). Dynamic datasets were computed into 90-100 data sets by motion coherence image processing (MCIP). Next, time-density curves (TDCs) for coronary arteries with a diameter >3mm were automatically calculated for all phases using MCIP. On the basis of the maximum slope method, coronary flow index (CFI) was defined as the ratio of the maximum upslope of coronary artery attenuation to the upslope of ascending aorta attenuation on the TDC, and was used to quantify coronary flow. CFIs for the proximal and distal sites of coronary arteries with mild-to-moderate stenosis were calculated. Coronary territories were categorized as non-ischemic or ischemic by MPS. Receiver-operating-characteristic (ROC) analysis was performed to determine the optimal cutoff for CFI to detect ischemia. RESULTS: Distal CFI was significantly lower for ischemia (0.26±0.08) than for non-ischemia (0.50±0.17, p<0.0001). No significant difference in proximal CFI was seen between ischemia (0.55±0.23) and non-ischemia (0.62±0.24). ROC analysis revealed 0.39 as the optimal cutoff for distal CFI to detect ischemia, with C-statistics of 0.91, 100% sensitivity, and 75% specificity. CONCLUSIONS: This novel imaging technique allows coronary flow quantification using heart-DCT. Distal CFI can detect myocardial ischemia derived from intermediate coronary stenosis.