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Yen-Wen Wu

Publications and source records attributed to Yen-Wen Wu.

At least 19 recordsLinked to original sources
PubMed2006

Prevalence of concomitant atherosclerotic arterial diseases in patients with significant cervical carotid artery stenosis in Taiwan.

BACKGROUND: Atherosclerotic stenosis of extracranial carotid arteries is an important cause of ischemic stroke in Taiwan, an ethnic Chinese population. Concurrent atherosclerotic arterial disease is an important issue in the management of patients with carotid stenosis, but its prevalence and extent are unknown. METHODS: One hundred and sixty-three consecutive patients with angiographically proven significant cervical carotid artery stenosis (>or=50% stenosis) were enrolled in this study. Angiography was done to document concurrent coronary, renal, and limb artery stenosis. Clinical symptoms and signs were also correlated with the angiographic findings. RESULTS: One or more significant concurrent arterial stenotic disease was found in 73% of the patients. The most frequent were coronary artery disease, found in 68% of the patients, while renal artery stenosis and limb artery stenosis were found in 20% and 21% of the patients, respectively. Age, diabetes, history of angina pectoris, intermittent claudication, and asymmetric arm blood pressures were significantly associated with the presence of concurrent arterial stenosis. However, 41% of the patients with concurrent coronary artery disease did not have any clinical symptoms or history of myocardial infarction. CONCLUSIONS: Our data indicated that concurrent advanced and extensive arterial disease is common in patients with significant cervical carotid stenosis, and also suggest the importance of global evaluation of systemic atherosclerosis in these patients to achieve optimal management.

Adult↗
PubMed2006

Intravascular ultrasound evidence of angiographically silent allograft vasculopathy inversely correlates with circulating level of hepatocyte growth factor.

BACKGROUND: Cardiac allograft vasculopathy (CAV) is the major determinant of long-term survival after heart transplantation. The characteristic diffuse concentric intimal thickening of CAV detected by intravascular ultrasound (IVUS) imaging may not be perceivable on coronary angiogram. Previous studies of hepatocyte growth factor (HGF) in murine models suggested the protective effects on vascular endothelium and allograft survival. However, the possible role of circulating HGF that contributes to the development of CAV in human is unclear. METHODS: IVUS was used to assess the left anterior descending coronary arteries of 47 patients who had survived cardiac transplantation for more than 1 year and had no angiographically detectable CAV. The IVUS measurements for the extent of intimal hyperplasia, including volume index (calculated as [total plaque volume/total vessel volume] x 100) and maximum area stenosis, were compared with plasma levels of HGF by linear regression analyses. RESULTS: The volume index significantly correlated with maximum area stenosis in the IVUS measurements (r = 0.90, p < 0.0001). Both volume index and maximum area stenosis inversely correlated with plasma HGF levels (r = -0.39, p = 0.007 and r = -0.42, p = 0.003, respectively). CONCLUSIONS: In angiographically silent CAV, circulating HGF may have a protective effect on vascular endothelium and thus attenuate the severity of intimal hyperplasia.

Adult↗
PubMed2006

Structural and functional assessment of arrhythmogenic right ventricular dysplasia/cardiomyopathy by multi-slice computed tomography: comparison with cardiovascular magnetic resonance.

Arrhythmogenic right ventricular dysplasia/cardiomyopathy (ARVD/C) is an uncommon inheritable cardiomyopathy involving predominant right ventricle with progressive fibrofatty tissue replacement. An integrated assessment of electrical, functional and anatomic abnormalities, in addition to personal and family history would be used to diagnose this disease entity. We present the case of a 69-year-old man with a history of sustained ventricular tachycardia. Fatty infiltration and regional wall motion abnormalities over biventricular myocardium were clearly demonstrated by cardiac 64-slice computed tomography (CT), as consistent with magnetic resonance imaging. Thus, multi-slice CT may have a significant role in the assessment and follow-up of patients with ARVD/C by providing excellent structural, functional assessment and tissue characterization.

Aged↗
PubMed2006

Identification of lipomatous metaplasia in old infarcted myocardium by cardiovascular magnetic resonance and computed tomography.

Lipomatous metaplasia of myocardium after myocardial infarction (MI) is less reported, and the exact prevalence and clinical implications of this phenomenon are unclear. A case of lipomatous metaplasia after MI evaluated with cardiovascular magnetic resonance (CMR) and computed tomography (CT) is presented. The presence of lipomatous metaplasia could not be easily differentiated from scar simply by the delayed-enhanced images. Loss of signal on TrueFISP cine MRI can be a hint. A pre-contrast T1-weighted image with or without frequency-selective fat suppression is useful in order to verify the existence of lipomatous metaplasia on CMR.

Humans↗
PubMed2006

Evaluation of three-dimensional navigator-gated whole heart MR coronary angiography: the importance of systolic imaging in subjects with high heart rates.

PURPOSE: To evaluate the influence of heart rate (HR) on magnetic resonance coronary angiography (MRCA) image quality in diastolic and systolic phases. MATERIALS AND METHODS: Twenty-seven healthy volunteers (9 men; 33+/-9 years, HR 53-110 bpm), were evaluated with the electrocardiography and three-dimensional navigator-gating MRCA in a 1.5-T MR scanner (Avanto, Siemens) in diastolic and systolic phases (steady-state free precession; TR/TE/flip angle=3.2 ms/1.6 ms/90 degrees). The timing of scanning was individually adapted to the cardiac rest periods obtained in the prescanning, by visually identifying when the movement of right coronary artery was minimized during diastole and systole. Images of two phases were side-by-side compared on a four-point scale (from 1=poor to 4=excellent visibility; score of 3 or 4 as diagnostic). RESULTS: Of 13 subjects with HR < or =65 bpm (low HR group, mean 59.8+/-4.9 bpm, range 53-65), the image quality scores were significantly better than that with higher heart rates (73.9+/-9.0 bpm, range 68-110) in diastolic MRCA. The image quality was significantly improved during systole in high HR group. Overall, 91.3% of low HR group had MRCA image of diagnostic quality acquired at diastole, while 88.3% of high HR group had diagnostic images at systole by segmental analysis (p=NS). CONCLUSIONS: MRCA at systole offered superior quality in patients with high heart rates.

Adult↗
PubMed2006

Complementary appearance of glucose and lipid metabolism in cardiac sarcoidosis.

Sarcoidosis is a non-caseating granulomatous systemic disease of unknown pathogenesis, and cardiac involvement is the most important prognostic factor. We have evaluated the value of the combined study of F-18 fluoro-2-deoxyglucose positron emission tomography and iodine-123 labeled 15-(p-iodophenyl)-3R,S-methylpentadecanoic acid single-photon emission tomography for the assessment of cardiac involvement of sarcoidosis, by comparing the findings with gadolinium magnetic resonance in a patient with histologically-proven cardiac sarcoidosis.

Aged↗
PubMed2006

Enhanced external counterpulsation reduces lung/heart ratio at stress in patients with coronary artery disease.

Enhanced external counterpulsation (EECP) is a recently approved treatment modality for patients with angina and heart failure. However, the efficacy of EECP on left ventricular (LV) function has not been well established. The study was aimed to determine whether EECP leads to an improvement in objective parameters of LV function. Patients with coronary artery disease (n = 10) who showed evidence of stress-induced myocardial ischemia despite conventional medical or surgical therapies were enrolled and received EECP therapy for a total of 35 h. The therapeutic effects of EECP were examined by thallium-201 single-photon emission computed tomography (201Tl-SPECT). Compared with baseline, the lung/heart ratio at stress decreased significantly from 0.40 +/- 0.08 to 0.35 +/- 0.08 (p = 0.001) at 1 month and 0.33 +/- 0.10 (p = 0.03) at 6 months following EECP treatment. LV ejection fraction marginally improved from 56.7 +/- 7.7% to 57.6 +/- 5.9% (p = 0.382) at 1 month and to 60.1 +/- 8.6% (p = 0.062) at 6 months after EECP therapy, although not statistically significant. We concluded that EECP improved LV function, shown as the reduction of lung/heart ratio at stress, in patients with coronary artery disease, up to 6 months after EECP treatment.

Coronary Artery Disease↗
PubMed2005

Usefulness of progressive inhomogeneity of myocardial perfusion and chronotropic incompetence in detecting cardiac allograft vasculopathy: evaluation with dobutamine thallium-201 myocardial SPECT.

BACKGROUND: The aim of the study was to investigate the value of longitudinal follow-up of dobutamine thallium-201 single photon emission tomography ((201)Tl SPECT) in the development of significant cardiac allograft vasculopathy (CAV) after orthotopic heart transplantation. METHODS: We studied 38 cardiac recipients (mean age 57 +/- 12 years) who underwent at least two follow-up dobutamine (201)Tl SPECT since January 1998. All patients had normal coronary angiography and normal left ventricular function initially. RESULTS: After 2.3 +/- 1.8 years, 12 patients developed significant CAV and there were 4 cardiac deaths (1 died suddenly). Of the 99 scans retrospectively analyzed, patients with significant CAV had elevated values of inhomogeneity score, lung/heart ratio (LHR) at stress and lower left ventricular ejection fraction (all p < 0.05). The higher values of inhomogeneity were significantly correlated with higher stress LHR (r = 0.301, p = 0.021), and lower ejection fraction (r = -0.379, p < 0.001). Progressive inhomogeneity was noted in all heart recipients, and more rapid, although statistically insignificant, in patients who developed significant CAV. Ten patients had inadequate chronotropic response to dobutamine infusion up to 40 mug/kg/min in the follow-up studies. The late onset of chronotropic incompetence was an independent predictor of CAV development (p = 0.03). CONCLUSIONS: Progressive inhomogeneity of myocardial perfusion, higher lung uptake at stress and chronotropic incompetence assessed by dobutamine (201)Tl myocardial SPECT provide incremental diagnostic value in detecting significant CAV.

Adrenergic beta-Agonists↗
PubMed2005

Diagnostic and prognostic value of dobutamine thallium-201 single-photon emission computed tomography after heart transplantation.

BACKGROUND: Cardiac allograft vasculopathy (CAV) is a major cause of mortality in heart transplant recipients. We investigated the diagnostic and prognostic value of dobutamine thallium-201 ((201)Tl) single-photon emission computed tomography (SPECT) in heart transplant recipients. METHODS: We studied 47 patients (age 51.6 +/- 11.7 years, 37 men), at a mean of 34.0 +/- 21.4 months after heart transplant, who received dobutamine (201)Tl SPECT, echocardiography and coronary angiography within 1 month of each other. SPECT was considered abnormal in the presence of reversible or fixed defects in >/=2 segments. Significant CAV was defined as >/=50% luminal stenosis. RESULTS: Coronary angiograms were normal in 37 patients. Non-significant CAV was detected in 1 patient and significant CAV in 9 patients. The sensitivity, specificity, positive predictive value and negative predictive value of SPECT for the detection of significant angiographic CAV were 89%, 71%, 42% and 96%, respectively. Large reversible perfusion defects (>/=6 segments) always indicated significant CAV. In patients with normal left ventricular function, a lung/heart ratio (LHR) of >/=0.37 during stress was also an independent predictor of significant CAV (odds ratio 15.5, p = 0.04). A higher stress LHR was associated with greater vessel involvement (r = 0.516, p = 0.0002). Patients with impaired left ventricular function also had higher stress and resting LHR. Over 40.3 +/- 21.9 months after the first SPECT, 1 patient developed significant angiographic CAV and another 4 had cardiac death. Large reversible perfusion defect was a significant predictor of cardiac death (p = 0.002). CONCLUSIONS: Dobutamine (201)Tl SPECT is a useful method for detecting patients with significant CAV and assessing prognosis. It is reasonable and safe to design individualized surveillance intensity of coronary angiography for post-transplant patients on the basis of non-invasive monitoring of dobutamine (201)Tl testing.

Adult↗
PubMed2005

99mTc-HL91 is inferior to 201Tl in scintigraphic detection of chronic myocardial ischaemia.

AIM: 99mTc-HL91 is a new hypoxia agent and can identify acutely ischaemic viable myocardium in a canine model using a standard gamma camera. The purpose of the study was to determine whether this tracer could be used to detect regional ischaemia in chronic ischaemic myocardium in a swine model. METHOD: Using a porcine model of chronic myocardial ischaemia, five mini-pigs with proximal left anterior descending artery (LAD) stenoses were studied. Injection of 462.5 MBq (12.5 mCi) 99mTc-HL91 was followed by imaging over 2 h. Coronary angiography and dipyridamole stress-re-injection 201Tl single photon emission computed tomography (SPECT) were performed within 1 day of each other. RESULTS: None of the five pigs demonstrated positive hot 99mTc-HL91 uptake throughout the 2 h imaging, whereas four of the five animals showed significant myocardial ischaemia on 201Tl SPECT. The region of interest analysis of LAD/left circumflex artery count ratios at 1 and 2 h demonstrated similar 99mTc-HL91 uptake and retention in chronic ischaemic as well as non-ischaemic myocardium. CONCLUSION: 99mTc-HL91 is inferior to 201Tl in scintigraphic detection of chronic myocardial ischaemia.

Angiography↗
PubMed2005

Early detection of splenic metastasis of lung cancer by 18F-2-fluoro-2-deoxyglucose positron emission tomography.

Diagnosis of splenic involvement by lung cancer in the early stage is helpful for introducing proper treatment. We report a case of pulmonary adenocarcinoma with splenic metastasis which was first detected by 18F-2-fluoro-2-deoxyglucose (18F-FDG) positron emission tomography (PET). This 56-year-old male underwent left pneumonectomy, extensive lymph node dissection and postoperative adjuvant chemotherapy and radiotherapy. Because progressive elevation of carcinoembryonic antigen was detected 2 years after the operation, whole-body 18F-FDG PET was performed and revealed an 18F-FDG hypermetabolic spot in the splenic hilum. Although subsequent computed tomography (CT) did not reveal any lesions in the spleen, the second and third CT scans performed 10 and 13 months later confirmed the previous PET finding of splenic metastasis. This case suggests that 18F-FDG PET may be useful for early detection of splenic metastasis not visible on CT.

Early Diagnosis↗
PubMed2004

Using 18-fluoro-2-deoxyglucose positron emission tomography in detecting infectious endocarditis/endoarteritis: a preliminary report.

RATIONALE AND OBJECTIVES: We evaluated the effectiveness of positron emission tomography (PET) with 18-fluoro-2-deoxyglucose (FDG) in the detection of infectious endocarditis/endoarteritis. MATERIALS AND METHODS: For this study, we recruited 6 patients (4 women, 2 men; age range, 35 - 78 years; mean age, 55.8 +/- 16.8 years) who were clinically diagnosed as having infective endocarditis/endoarteritis by their echocardiographic findings and by Duke criteria. RESULTS: For all 6 patients, we also found increased FDG uptakes in the corresponding areas detected in echocardiography. CONCLUSION: FDG-PET appears to be a promising tool in diagnosing infective endocarditis/endoarteritis, and further prospective studies on a large scale to fully exploit the usefulness of FDG-PET for infective endocarditis/endoarteritis are needed.

Adult↗
PubMed2003

Value of circulating adhesion molecules in assessing cardiac allograft vasculopathy.

Circulating adhesion molecules have been implicated in the development of spontaneous and transplant coronary artery disease. We analyzed soluble (s) intercellular adhesion molecule 1 (sICAM-1), vascular cell adhesion molecule 1 (sVCAM-1), and sE-selectin levels from the coronary sinuses of 25 cardiac allograft recipients, and we correlated these molecules with the degree of acute rejection detected in endomyocardial biopsy specimens and the presence of transplant vasculopathy assessed with coronary angiography. We found that sVCAM-1 significantly increased in patients with transplant vasculopathy compared with those without transplant vasculopathy, whereas sE-selectin and sICAM-1 did not. Therefore, increased coronary sinus levels of sVCAM-1 is a reliable marker in assessing cardiac transplant vasculopathy.

Biomarkers↗
PubMed2003

Late atrioventricular block after heart transplantation.

Bradyarrhythmia requiring permanent pacing after heart transplantation remains a common problem. Sinus node dysfunction is the most common indication, and late onset of atrioventricular (AV) block has rarely been reported. We report the case of a patient who developed advanced AV block at 41 months after transplantation. Right bundle branch block with progressive increase of QRS complex duration was noted in serial electrocardiograms. At the time of late AV block development, the patient did not have acute rejection and coronary angiogram was normal. The mechanism of late onset of AV block is unclear, but it may be caused by progressive conduction.

Heart Block↗