Radiologic-Pathologic Correlation of Primary and Secondary Cardiomyopathies: MR Imaging and Histopathologic Findings in Hearts from Autopsy and Transplantation.

Cardiac magnetic resonance (MR) imaging with late gadolinium enhancement (LGE) is used to detect and assess the myocardial damage seen with a variety of cardiomyopathies. Gadolinium-based contrast material accumulates in the expanded interstitial space of the myocardium. Areas with LGE correspond to replacement fibrosis, fibrofatty change, epithelioid granuloma, inflammatory cell infiltration, cardiomyocyte necrosis, and amyloid deposition-conditions that represent a focal increase in interstitial space. Areas without LGE correspond to interstitial or plexiform fibrosis, mildly degenerated cardiomyocytes, inflammatory cell infiltration, and diffuse amyloid deposition-conditions that represent diffuse increases in interstitial space. LGE MR imaging cannot depict these diffuse changes and does not enable quantitative evaluation of this increased interstitial space because on inversion-recovery MR images, the inversion time is adjusted to null the signal from normal-appearing or the least enhancing regions of the myocardium. Thus, the absence of LGE does not always indicate normal myocardial tissue. The use of current T1 mapping techniques enables one to overcome these drawbacks of LGE imaging, detect diffuse myocardial abnormalities, and perform quantitative analysis of the interstitial space. The authors describe the histopathologic and corresponding cardiac MR imaging findings of hypertrophic cardiomyopathy, dilated cardiomyopathy, arrhythmogenic right ventricular cardiomyopathy, cardiac sarcoidosis, giant cell myocarditis, and cardiac amyloidosis-mainly those seen on LGE MR images-as assessed by using whole-heart specimens obtained from autopsy or transplantation. ©RSNA, 2017.

Late gadolinium enhancement in cardiac amyloidosis: attributable both to interstitial amyloid deposition and subendocardial fibrosis caused by ischemia.

Gadolinium contrast agents used for late gadolinium enhancement (LGE) distribute in the extracellular space. Global diffuse myocardial LGE pronounced in the subendocardial layers is common in cardiac amyloidosis. However, the pathophysiological basis of these findings has not been sufficiently explained. A 64-year-old man was admitted to our hospital with leg edema and nocturnal dyspnea. Bence Jones protein was positive in the urine, and an endomyocardial and skin biopsy showed light-chain (AL) amyloidosis. He died of ventricular fibrillation 3 months later. 9 days before death, the patient was examined by cardiac magnetic resonance (CMR) imaging on a 3-T system. We acquired LGE data at 2, 5, 10, and 20 min after the injection of gadolinium contrast agents, with a fixed inversion time of 350 ms. Myocardial LGE developed sequentially. The myocardium was diffusely enhanced at 2 min, except for the subendocardium, but LGE had extended to almost the entire left ventricle at 5 min and predominantly localized to the subendocardial region at 10 and 20 min. An autopsy revealed massive and diffused amyloid deposits in perimyocytes throughout the myocardium. Old and recent ischemic findings, such as replacement fibrosis and coagulative myocyte necrosis, were evident in the subendocardium. In the intramural coronary arteries, mild amyloid deposits were present within the subepicardial to the mid layer of the left ventricle, but no stenotic lesions were evident. However, capillaries were obstructed by amyloid deposits in the subendocardium. In conclusion, the late phase of dynamic LGE (at 10 and 20 min) visualized in the subendocardium corresponded to the interstitial amyloid deposition and subendocardial fibrosis caused by ischemia in our patient.

Comparison of cardiovascular mortality in the Great East Japan and the Great Hanshin-Awaji Earthquakes　- a large-scale data analysis of death certificates.

BACKGROUND: Large earthquakes have been associated with cardiovascular disease (CVD) mortality. In Japan, the 1995 Great Hanshin-Awaji (H-A) Earthquake was an urban-underground-type earthquake, whereas the 2011 Great East Japan (GEJ) Earthquake was an ocean-trench type. In the present study, we examined how these different earthquake types affected CVD mortality. METHODS AND RESULTS: We examined death certificate data from 2008 to 2012 for 131 municipalities in Iwate, Miyagi, and Fukushima prefectures (n=320,348) and from 1992 to 1996 for 220 municipalities in Hyogo, Osaka, and Kyoto prefectures (n=592,670). A Poisson regression model showed significant increases in the monthly numbers of acute myocardial infarction (AMI)-related deaths (incident rate ratio [IRR] GEJ=1.34, P=0.001; IRR of H-A=1.57, P<0.001) and stroke-related deaths (IRR of GEJ=1.42, P<0.001; IRR of H-A=1.33, P<0.001) after the earthquakes. Two months after the earthquakes, AMI deaths remained significant only for H-A (IRR=1.13, P=0.029). When analyzing the standardized mortality ratio (SMR) after the earthquakes using the Cochran-Armitage trend test, seismic intensity was significantly associated with AMI mortality for 2 weeks after both the GEJ (P for trend=0.089) and H-A earthquakes (P for trend=0.005). CONCLUSIONS: Following the GEJ and H-A earthquakes, there was a sharp increase in CVD mortality. The effect of the disaster was sustained for months after the H-A earthquake, but was diminished after the GEJ Earthquake.

[Heart transplantation and ventricular assit systems].

Since the organ transplantation law was passed, we performed 50 heart transplantation at National Cerebral and Cardiovascular Center. Of those, 2 patients have been doing well over 13 years and 10 years survival rate was 93.4%.During those years, we performed 139 applications of left ventricular assist systems( LVAS). Initially, extracorporeal LVASs had been used. Now, 2 implantable LVAS were approved by medical insurance as bridge to transplant in 2011. Now, our 1st option as bridge to transplantation(BTT) is implantable LVAS.

Dynamic late gadolinium enhancement simply quantified using myocardium to lumen signal ratio: normal range of ratio and diffuse abnormal enhancement of cardiac amyloidosis.

PURPOSE: To detect abnormal myocardial tissue in patients with diffuse myocardial disease, we propose a simple technique of late gadolinium enhancement (LGE) using routine myocardial imaging modalities. MATERIALS AND METHODS: We retrospectively reviewed LGE images from 51 patients with normal myocardium and 10 patients with pathologically proven cardiac amyloidosis (CA). We obtained sequential LGE images from patients at 2, 5, 10, and 20 minutes after injection of Gd-DTPA (0.15 mmol/kg) with a fixed inversion time of 300 msec. We evaluated the signal intensity ratio of the myocardium to the left ventricular lumen (M/L) in one long and two short axial sections within 463 and 120 segments of normal myocardium and CA, respectively. Visually unenhanced and enhanced regions of myocardium were evaluated in each segment of patients with CA. RESULTS: Among normal myocardium, M/L (means ± standard deviation; SD) was stable with time (2, 5, 10, and 20 min: 0.34 ± 0.03, 0.31 ± 0.05, 0.34 ± 0.07, and 0.42 ± 0.11, respectively). The calculated M/L of unenhanced (0.60 ± 0.20, 0.68 ± 0.19, 0.76 ± 0.20, and 1.09 ± 0.25, respectively) and enhanced myocardium (0.77 ± 0.27, 0.99 ± 0.29, 1.20 ± 0.40, and 1.45 ± 0.54, respectively) in patients with CA was significantly greater than that seen for the normal myocardium at each time and increased over time. CONCLUSION: In patients with CA, diffuse myocardial abnormalities can be demonstrated using M/L, and this technique may be useful for the characterization of other myocardial diseases.

Assessment of calcified carotid plaque volume: comparison of contrast-enhanced dual-energy CT angiography and native single-energy CT.

OBJECTIVE: The purpose of this study was to compare estimates of calcified plaque volume in the carotid arteries based on contrast-enhanced dual-energy CT angiograms with volume estimates based on native CT scans. CONCLUSION: Detection of hard plaque in the carotid arteries with dual-energy CT angiography was successful in all patients. Estimates of calcified plaque volume based on dual-energy CT angiograms correlated well with those based on native single-energy CT scans but at a lower attenuation threshold (130 HU as opposed to 180 HU) were underestimates compared with those on the native CT scans.

Lung perfused blood volume images with dual-energy computed tomography for chronic thromboembolic pulmonary hypertension: correlation to scintigraphy with single-photon emission computed tomography.

OBJECTIVE: The purpose of this study was to evaluate the feasibility and diagnostic utility of lung perfused blood volume (LPBV) images generated by dual-energy computed tomography (CT), as compared with pulmonary perfusion scintigraphy, for patients with chronic thromboembolic pulmonary hypertension. METHODS: Patients (n = 51) with chronic pulmonary thromboembolic embolism were examined by dual-source CT in dual-energy mode. Lung perfused blood volume images were generated by analysis of the iodine content of the lung parenchyma using dual-energy data. Pulmonary perfusion defects were evaluated on a segment-by-segment basis in images obtained by both LPBV and pulmonary scintigraphy. Findings suggestive of chronic thromboembolic pulmonary hypertension in CT pulmonary angiography were analyzed. RESULTS: All examinations were acquired without complications, and the contrast enhancement of the pulmonary artery was sufficient for diagnosis of vascular thromboses. In the LPBV images, in 76 (8.3%) of 918 segments, it was difficult to assess perfusion because of artifacts. The agreement between the 2 modalities was good (κ = 0.70). The sensitivity of LPBV in detecting perfusion defects was 96%; the specificity was 76%; the positive predictive value was 94%, and the negative predictive value was 29%. CONCLUSIONS: Lung perfused blood volume imaging by dual-energy CT is feasible for the evaluation of pulmonary perfusion and is comparable to pulmonary scintigraphy. It is possible to evaluate vessels and pulmonary perfusion with CT pulmonary angiography and LPBV images and to assess pulmonary perfusion more definitively in diagnosing chronic pulmonary thromboembolic embolism.

Exogenous insulin-like growth factor 1 attenuates cisplatin-induced muscle atrophy in mice.

BACKGROUND: A reduction in the skeletal muscle mass worsens the prognosis of patients with various cancers. Our previous studies indicated that cisplatin administration to mice caused muscle atrophy. This is a concern for human patients receiving cisplatin. The insulin-like growth factor 1 (IGF-1)/phosphoinositide 3-kinase (PI3K)/Akt pathway stimulates the rate of protein synthesis in skeletal muscle. Thus, IGF-I can be a central therapeutic target for preventing the loss of skeletal muscle mass in muscle atrophy, although it remains unclear whether pharmacological activation of the IGF-1/PI3K/Akt pathway attenuates muscle atrophy induced by cisplatin. In this study, we examined whether exogenous recombinant human IGF-1 attenuated cisplatin-induced muscle atrophy. METHODS: Male C57BL/6J mice (8-9 weeks old) were injected with cisplatin or saline for four consecutive days. On Day 5, quadriceps muscles were isolated. Mecasermin (recombinant human IGF-1) or the vehicle control was subcutaneously administered 30 min prior to cisplatin administration. A dietary restriction group achieving weight loss equivalent to that caused by cisplatin administration was used as a second control. C2C12 myotubes were treated with cisplatin with/without recombinant mouse IGF-1. The skeletal muscle protein synthesis/degradation pathway was analysed by histological and biochemical methods. RESULTS: Cisplatin reduced protein level of IGF-1 by about 85% compared with the vehicle group and also reduced IGF-1/PI3K/Akt signalling in skeletal muscle. Under this condition, the protein levels of muscle ring finger protein 1 (MuRF1) and atrophy gene 1 (atrogin-1) were increased in quadriceps muscles (MuRF1; 3.0 ± 0.1 folds, atrogin-1; 3.0 ± 0.3 folds, P < 0.001, respectively). The administration of a combination of cisplatin and IGF-1 significantly suppressed the cisplatin-induced downregulation of IGF-1/PI3K/Akt signalling and upregulation of MuRF1 and atrogin-1 (up to 1.6 ± 0.3 and 1.5 ± 0.4 folds, P < 0.001, respectively), resulting in diminished muscular atrophy. IGF-1 showed similar effects in cisplatin-treated C2C12 myotubes, as well as the quadriceps muscle in mice. CONCLUSIONS: The downregulation of IGF-1 expression in skeletal muscle might be one of the factors playing an important role in the development of cisplatin-induced muscular atrophy. Compensating for this downregulation with exogenous IGF-1 suggests that it could be a therapeutic target for limiting the loss of skeletal muscle mass in cisplatin-induced muscle atrophy.

CT-pathologic correlation of non-calcified atherosclerotic arterial plaques: a study using carotid endarterectomy specimens.

OBJECTIVE: Pathologic features of atherosclerotic plaques on CT are not established. We compared CT values among pathologically confirmed plaque constituents and evaluated their ability to distinguish plaque constituents. METHODS: 50 histopathological images of carotid endarterectomy samples from 10 males and 2 females (age 54-74 years, average 65.9 years) were examined. We compared pre-operative CT [pre-contrast (CT-P), early post-contrast phase (CT-E), delayed post-contrast phase (CT-D)] of lipid-rich necrotic core (NC) and fibrous tissue (F) plaque components with pathological images. The ability of features to differentiate plaque components using several discrimination techniques were compared. RESULTS: CT values of NC and F were 36 ± 13, 45 ± 11 (mean ± standard deviation, Hounsfield unit, HU), 41 ± 17, 69 ± 18, and 44 ± 16, 70 ± 13 in CT-P (p < 0.01), CT-E (p < 0.0001), and CT-D (p < 0.0001), respectively. The threshold, sensitivity, and accuracy for distinguishing NC from F were 44 HU, 74%, and 68%; 55 HU, 85%, and 85%; and 63 HU, 92%, and 84% in CTP, CT-E, and CT-D, respectively. CT-P had lower accuracy than CT-E and CT-D (both p < 0.05), but CT-E and CT-D were similar. CT-E and CT-D yielded 90 and 91% sensitivity and accuracy, respectively in linear discrimination analysis. CONCLUSION: In both pre- and post-contrast CT, CT values were lower in NC than F. Although values overlapped, using two-phase post-contrast CTs improved discrimination ability. ADVANCES IN KNOWLEDGE: Our findings may help to establish computer-aided diagnosis of vulnerable atherosclerotic plaques in future.

Dual-energy direct bone removal CT angiography for evaluation of intracranial aneurysm or stenosis: comparison with conventional digital subtraction angiography.

Dual-energy CT can be applied for bone elimination in cerebral CT angiography (CTA). The aim of this study was to compare the results of dual-energy direct bone removal CTA (DE-BR-CTA) with those of digital subtraction angiography (DSA). Twelve patients with intracranial aneurysms and/or ICA stenosis underwent a dual-source CT in dual-energy mode. Post-processing software selectively removed bone structures using the two energy data sets. Three-dimensional images with and without bone removal were reviewed and compared to DSA. Dual-energy bone removal was successful in all patients. For 10 patients, bone removal was good and CTA maximum-intensity projection (MIP) images could be used for vessel evaluation. For two patients, bone removal was moderate with some bone remnants, but this did not inhibit the three-dimensional visualization. Three aneurysms adjacent to the skull base were only partially visible in conventional CTA but were fully visible in DE-BR-CTA. In five patients with ICA stenosis, DE-BR-CTA revealed the stenotic lesions on the MIP images. The correlation between DSA and DE-BR-CTA was good (R (2)=0.822), but DE-BR-CTA led to an overestimation of stenosis. DE-BR-CTA was able to eliminate bone structure using only a single CT data acquisition and is useful to evaluate intracranial aneurysms and stenosis.

Dual-energy CT head bone and hard plaque removal for quantification of calcified carotid stenosis: utility and comparison with digital subtraction angiography.

We evaluated quantification of calcified carotid stenosis by dual-energy (DE) CTA and dual-energy head bone and hard plaque removal (DE hard plaque removal) and compared the results to those of digital subtraction angiography (DSA). Eighteen vessels (13 patients) with densely calcified carotid stenosis were examined by dual-source CT in the dual-energy mode (tube voltages 140 kV and 80 kV). Head bone and hard plaques were removed from the dual-energy images by using commercial software. Carotid stenosis was quantified according to NASCET criteria on MIP images and DSA images at the same plane. Correlation between DE CTA and DSA was determined by cross tabulation. Accuracies for stenosis detection and grading were calculated. Stenosis could be evaluated in all vessels by DE CTA after applying DE hard plaque removal. In contrast, conventional CTA failed to show stenosis in 13 out of 18 vessels due to overlapping hard plaque. Good correlation between DE plaque removal images and DSA images was observed (r (2) = 0.9504) for stenosis grading. Sensitivity and specificity to detect hemodynamically relevant (>70%) stenosis was 100% and 92%, respectively. Dual-energy head bone and hard plaque removal is a promising tool for the evaluation of densely calcified carotid stenosis.

Triglyceride deposit cardiomyovasculopathy: a rare cardiovascular disorder.

Triglyceride deposit cardiomyovasculopathy (TGCV) is a phenotype primarily reported in patients carrying genetic mutations in PNPLA2 encoding adipose triglyceride lipase (ATGL) which releases long chain fatty acid (LCFA) as a major energy source by the intracellular TG hydrolysis. These patients suffered from intractable heart failure requiring cardiac transplantation. Moreover, we identified TGCV patients without PNPLA2 mutations based on pathological and clinical studies. We provided the diagnostic criteria, in which TGCV with and without PNPLA2 mutations were designated as primary TGCV (P-TGCV) and idiopathic TGCV (I-TGCV), respectively. We hereby report clinical profiles of TGCV patients. Between 2014 and 2018, 7 P-TGCV and 18 I-TGCV Japanese patients have been registered in the International Registry. Patients with I-TGCV, of which etiologies and causes are not known yet, suffered from adult-onset severe heart disease, including heart failure and coronary artery disease, associated with a marked reduction in ATGL activity and myocardial washout rate of LCFA tracer, as similar to those with P-TGCV. The present first registry-based study showed that TGCV is an intractable, at least at the moment, and heterogeneous cardiovascular disorder.

Sex differences in impact of coronary artery calcification to predict coronary artery disease.

OBJECTIVE: To assess sex-specific differences regarding use of conventional risks and coronary artery calcification (CAC) to detect coronary artery disease (CAD) using coronary CT angiography (CCTA). METHODS: The Nationwide Gender-specific Atherosclerosis Determinants Estimation and Ischemic Cardiovascular Disease Prospective Cohort study is a prospective, multicentre, nationwide cohort study. Candidates with suspected CAD aged 50-74 years enrolled from 2008 to 2012. The outcome was obstructive CAD defined as any stenosis ≥50% by CCTA. We constructed logistic regression models for obstructive CAD adjusted for conventional risks (clinical model) and CAC score. Improvement in discrimination beyond risks was assessed by C-statistic; net reclassification index (NRI) for CAD probability of low (<30%), intermediate (30%-60%) and high (≥60%); and risk stratification capacity. RESULTS: Among 991 patients (456 women, 535 men; 65.2 vs 64.4 years old), women had lower CAC scores (median, 4 vs 60) and lower CAD prevalence (21.7% vs 37.0%) than men. CAC significantly improved model discrimination compared with clinical model in both sexes (0.66-0.79 in women vs 0.61-0.83 in men). The NRI for women was 0.33, which was much lower than that for men (0.71). Adding CAC to clinical model had a larger benefit in terms of moving an additional 43.3% of men to the most determinant categories (high or low risk) compared with -1.4% of women. CONCLUSIONS: The addition of CAC to a prediction model based on conventional variables significantly improved the classification of risk in suspected patients with CAD, with sex differences influencing the predictive ability. TRIAL REGISTRATION NUMBER: UMIN-CTR Clinical Trial: UMIN000001577.

Multidetector CT angiography using a dual-head power injector and bolus tracking for the diagnosis of aortic aneurysms at reduced contrast material dosage.

RATIONALE AND OBJECTIVES: To establish the utility of multidetector computed tomography (CT) angiography using dual-head power injector in the diagnosis of aortic diseases. METHODS: In a prospective study, 151 patients with aortic diseases were examined by four-detector CT. Scanning was performed using bolus tracking technique. In all patients nonionic contrast was injected at the rate of 1.5 mL/sec. One hundred one patients were examined with dual-head power injector using 0.6 mL/kg contrast flushed by 30 mL of saline solution (group D). Fifty patients were examined with single-head power injector using 1.0 mL/kg contrast only (group S). We evaluated CT values at descending aorta, upper abdominal aorta, abdominal aortic bifurcation, and bilateral common femoral arteries. RESULTS: There were no statistically significant difference of CT values at descending aorta, upper abdominal aorta, abdominal aortic bifurcation, and right common femoral artery. At left common femoral artery, CT values in group D were higher than those in group S with statistically difference (P < .05). In group D, about 40% dose reduction was achieved without reducing image qualities. CONCLUSION: Multidetector CT angiography using dual-head power injector was valuable for the contrast dose reduction of aortic diseases.

Evaluation of the usefulness of color digital summation radiography in temporally sequential digital radiographs: a phantom study.

PURPOSE: The purpose of this study was to assess the usefulness of color digital summation radiography (CDSR) for detection of nodules on chest radiographs by observers with different levels of experience. MATERIALS AND METHODS: A total of 30 radiographs of chest phantoms with abnormalities and 30 normal ones were arranged at random. Set A was conventional radiographs only. Set B consisted of both conventional radiographs and CDSR images, which were colored with magenta. Five chest radiologists and five residents evaluated both image sets on a TFT monitor. The observers were asked to rate each image set using a continuous rating scale. The reading time for each set was also recorded. RESULTS: In set A, the performance of chest radiologists was significantly superior to that of the residents (P < 0.05). However, in set B, there was no significant difference in the performance of the chest radiologists and the residents. In both observer groups, the mean reading time per case in set B was significantly shorter than that in set A (P < 0.01). CONCLUSION: By using CDSR, the detection capability of observers with little experience improves and is comparable to that of experienced observers. Moreover, the reading time becomes much shorter using CDSR.

Novel display technique for reference images for visibility of temporal change on radiographs--color digital summation radiography.

PURPOSE: The present study investigated color digital summation radiography (CDSR) as a novel display technique for reference images for the visibility of temporal change on radiographs. In CDSR, only the parts with temporal differences are displayed in color. Moreover, all other parts are displayed in gray scale. MATERIALS AND METHODS: CDSR was defined as "radiographs combined by the additive color mixture method". The visibility of simulated nodules located in the lung fields and mediastinum was evaluated by 12 radiologists (mean experience, 9.8 years; range, 1-26 years) for 24 conventional radiographs and CDSR for 6 color patterns. A five-point rating system (5, very good; 4, good; 3, adequate; 2, poor; 1, very poor) was used. RESULTS: The mean scores (average +/- standard deviation) for the visibility of simulated nodules were as follows: magenta, 3.88 +/- 0.90; blue, 3.08 +/- 0.72; green, 3.04 +/- 0.86; red, 3.00 +/- 0.98; cyan, 2.71 +/- 0.86; and yellow, 2.50 +/- 0.72. Compared to conventional radiography in gray scale, at 1.21 +/- 0.41, all six color patterns for CDSR displayed significantly improved scores (p<0.001). CONCLUSION: CDSR might represent a useful technique for reference images from chest digital radiography.

Evaluation of usefulness of color digital summation radiography for solitary pulmonary nodules on chest radiographs.

PURPOSE: The aim of this study was to evaluate the usefulness of novel color digital summation radiography (CDSR) for detecting solitary pulmonary nodules on chest radiographs by observers with different levels of experience. MATERIALS AND METHODS: A total of 30 healthy controls and 30 patients with newly detected solitary pulmonary nodules were evaluated. Six radiologists and five residents evaluated three image sets: set A, current and prior radiographs only; set B, set A with temporal subtraction images; and set C, set A with CDSR. The observers were asked to rate each image set using a continuous rating scale. In addition, the reading time required for each set was recorded. RESULTS: The radiologists showed no significant differences in the mean A(z) value between set A, set B, and set C. However, the residents showed significant differences between set A and set B and between set A and set C. In addition, for set B and set C, the mean reading time per case of all readers was significantly shorter than that for set A. CONCLUSION: The detection capability of observers with little experience is comparable to that of experienced observers when reading radiographs with temporal subtraction images or with CDSR. The usefulness of CDSR is comparable to that of temporal subtraction.

Evaluation of organized thrombus in distal pulmonary arteries in patients with chronic thromboembolic pulmonary hypertension using cone-beam computed tomography.

PURPOSE: Balloon pulmonary angioplasty (BPA) is an emerging treatment for inoperable chronic thromboembolic pulmonary hypertension (CTEPH) patients. However, the approach to use to identify distal thrombi suitable for BPA has not yet been established. The purpose of this work was therefore to evaluate distal chronic thromboembolic lesions for BPA using cone-beam computed tomography (CBCT). MATERIALS AND METHODS: Thirty-two patients (men/women: 9/23) with CTEPH who underwent CBCT before BPA were enrolled. We assessed representative forms of chronic thromboembolic lesions in 94 segmental and/or 208 subsegmental branches according to CBCT and compared the results to the findings of selective angiography during BPA. RESULTS: We classified CTEPH lesions into five subtypes as follows: type 1a (11.1 %), webs; type 1b (14.4 %), web with severe narrowing of the subsegmental artery; type 2, (58.2 %) web and slits; type 3 (2.4 %), slits; and type 4 (13.9 %), pouch defect with incomplete obstruction of subsegmental branches or complete occlusion. In our study, 92.6 % of the CTEPH lesions diagnosed by CBCT were highly consistent with the findings of selective angiography during BPA. CONCLUSION: CBCT clearly revealed and classified distal lesions in CTEPH patients. The CBCT findings for distal lesions were highly consistent with those of selective angiography during BPA. CBCT could be a useful modality to detect target lesions before BPA.

Determination of timing for reoperation in patients after right ventricular outflow reconstruction.

After right ventricular (RV) outflow reconstruction, patients often develop postoperative outflow tract stenosis or pulmonary regurgitation, or both. The aim of this study was to assess the relation between RV hypertrophy, volume, pressure, and function and to provide indications for repeat surgery. We performed magnetic resonance imaging to measure RV volume, wall mass, and the ratio of mass to volume in 31 patients after RV outflow reconstruction and in 12 controls. Patients were divided into 2 groups, New York Heart Association class I and the repeat surgery group. The RV stress index was defined as RV peak systolic pressure/(mass to volume); RV ejection fraction (EF) was calculated by ventriculography. The RV stress index for the repeat surgery group was significantly higher than for the remaining groups (p <0.01). In the New York Heart Association class I and control groups, a significant inverse correlation was observed between RVEF and the RV stress index (r = -0.59, p <0.01). All patients in reoperation group whose RVEF decreased to <95% confidence limit of regression had symptoms of RV failure. The RV stress index decreased substantially after reoperation, but RVEF remained at <95% limits. These findings suggest that excess RV wall stress contributes to impaired RV performance. The RV stress-RVEF relation may be useful in assessing RV function and in establishing a surgical indication.