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C W Chiang

Publications and source records attributed to C W Chiang.

At least 37 records · Page 2Linked to original sources
PubMed1999

Gender differences in the presentation of adult obstructive hypertrophic cardiomyopathy with resting gradient: a study of 122 patients.

The present study investigated gender differences among adult patients with obstructive hypertrophic cardiomyopathy (OHCM) and resting gradient. Using outflow gradients >10 mmHg and the presence of asymmetrical septal hypertrophy of the left ventricle as inclusion criteria, 122 patients were identified among patients referred for echocardiographic examinations between May 1990 and October 1996. Clinical, echocardiographical and follow-up data were compared between male and female patients. The female patients were significantly older than male patients (mean age +/-SD 66.7+/-10.5 vs 54.8+/-12.5 years). The female patients had a smaller interventricular septal wall thickness, less frequent systolic anterior movement of the mitral valve, more frequent association with hypertension, and less frequent association with ischemic heart disease (IHD) and giant T wave inversion. In this study population, adult female patients presented with OHCM 12 years later than males. Whether this represents female patients' reluctance to seek medical attention early, a different disease process that affects predominantly elderly females, or a gender-specific end organ response to aging, hypertension, IHD and other processes, or the protective effects of estrogen remains to be determined.

Adolescent↗
PubMed1999

Extrasplenic pseudoaneurysm. The role of color flow Doppler ultrasound in diagnosis.

Pseudoaneurysm of the splenic artery has been rarely reported and the Doppler echocardiographic finding seldom described. Herein we report a rare case of huge extrasplenic pseudoaneurysm, which was detected by color flow Doppler ultrasonography and successfully treated by ligation of the splenic artery and resection of the pseudoaneurysm.

Aged↗
PubMed1999

Obstructive hypertrophic cardiomyopathy in Taiwanese adults.

The purpose of this study was to analyze the clinical profiles, echocardiographic findings, and mortality among adult Taiwanese patients with obstructive hypertrophic cardiomyopathy (HCM) at Chang Gung Memorial Hospital, a university-affiliated tertiary referral center in suburban Taipei. We reviewed the medical records of all adult (> 15 years of age) patients referred to our laboratory for echocardiographic examinations of cardiac diseases from May 1990 through December 1996. The diagnosis of obstructive HCM required an outflow gradient of above 10 mm Hg and the presence of asymmetric septal hypertrophy of the left ventricle. Follow-up information on was obtained from hospital records, questionnaires, interviews, or the National Death Certificate Registry. Of the 6.798 adults who underwent echocardiographic examinations during the study period 122 (1.79%) had obstructive HCM. The mean +/- standard deviation age of the patients was 62.2 +/- 12.6 years, and females predominated (n = 76, 62.3%). During the mean follow-up period of 3.2 years, the annual all-cause mortality rate was 4.7%. Most deaths were due to concurrent medical conditions. The annual cardiac mortality rate was 0.99%. Logistic regression analysis identified medication with calcium channel blockers as the only negative predictor (relative risk = 0.26, 95% confidence interval = 0.07-0.96) of all-cause mortality, and left atrial size as the only positive predictor (relative risk = 1.18, 95% confidence interval = 1.02-1.37) of cardiac mortality. Cox regression analysis confirmed the former association, but not the latter. Thus, in our institution, obstructive HCM had a low prevalence among adult patients referred for echocardiographic examination. These patients were elderly and often had other associated medical conditions. The high all-cause mortality rate was largely due to non-cardiac causes. These findings suggest that obstructive HCM tends to have a benign clinical course. Large atrial size could be an independent predictor of cardiac mortality, but this possibility requires further confirmation.

Aged↗
PubMed1998

Gender differences in baseline variables, therapies and outcomes in Chinese patients with acute myocardial infarction.

We prospectively studied the gender differences of baseline variables, therapies, and outcomes among a cohort of 369 Chinese patients with acute myocardial infarction from 1990 to 1995. There were 277 male and 92 female patients. The male gender had a younger mean (+/-SD) age (61.5+/-10.7 vs. 67.1+/-11.7 years, P<0.0001). Hypercholesterolemia (201.2+/-44.2 vs. 187.5+/-43.7 mg/dl, P=0.0111) and obesity (25.0 vs. 15.9%, P=0.0494) were more prominent in the female. Smoking was more prevalent in the male (78.3 vs. 18.5%, P<0.0001). The male group also had more frequent use of thrombolytic agents (19.1 vs. 9.8%, P=0.0377), beta-blockers (61.7 vs. 47.8%, P=0.0191) and heparin (25.3 vs. 12.0%, P=0.0075); but less use of angiotensin-converting enzyme inhibitors (6.9 vs. 15.2%, P=0.0149). The condition on admission was worse in the female group (Killip classification (1.5+/-0.9 vs. 1.9+/-1.0, P=0.0022), myocardial failure (8.7 vs. 2.9%, P=0.0178) and cardiomegaly (65.2 vs. 53.1%, P=0.0419). During a follow-up duration of 26.4+/-24.1 and 22.9+/-23.9 months respectively, the mortality rate was lower in the male (19.5 vs. 30.4%, P=0.0288). However after adjustment for the effect of age, the differences in Killip classification, myocardial failure, cardiomegaly and mortality became insignificant.

Aged↗
PubMed1998

Predictors of systemic embolism in patients with mitral stenosis. A prospective study.

BACKGROUND: Most studies of the predictors of systemic embolism in patients with mitral stenosis have been retrospective. OBJECTIVE: To prospectively study factors associated with systemic embolism in mitral stenosis. DESIGN: Prospective cohort study. SETTING: University-affiliated medical institution with 3000 beds. PATIENTS: 534 consecutive patients with a mitral valve area of 2.0 cm2 or less; 132 patients were in sinus rhythm, and 402 were in atrial fibrillation. MEASUREMENTS: Nine clinical and 10 echocardiographic variables were assessed for prediction of systemic embolism over a mean (+/- SD) follow-up of 36.9 +/- 22.5 months. Diagnosis of systemic embolism was based on symptoms and signs (sudden onset of peripheral arterial ischemic or neurologic manifestations without prodromes) and on findings on computed tomography, angiography, and surgery. RESULTS: For patients in sinus rhythm, age (relative risk [RR], 1.12 [95% CI, 1.04 to 1.21]), the presence of a left atrial thrombus (RR, 37.1 [CI, 2.82 to 487.8]), mitral valve area (RR, 16.9 [CI, 1.53 to 187.0]), and the presence of significant aortic regurgitation (RR, 22.4 [CI, 2.72 to 184.8]) were positively associated with embolism. For patients in atrial fibrillation, previous embolism (RR, 3.11 [CI, 1.66 to 5.85]) was positively associated with embolism; percutaneous balloon mitral commissurotomy (RR, 0.37 [CI, 0.18 to 0.79]) was a negative predictor. CONCLUSIONS: It may be prudent to give anticoagulants not only to patients in atrial fibrillation and patients with previous systemic embolism but also to those showing a left atrial thrombus or significant aortic regurgitation on echocardiography. Early percutaneous balloon mitral commissurotomy may also help prevent systemic embolism in patients with mitral stenosis.

Adult↗
PubMed1998

Catheterization-documented coronary artery disease in young Chinese adults.

We conducted a retrospective study among 31 young (age<40 years) Chinese patients with catheterization-documented coronary artery disease. Male gender and smoking were the most important risk factors. Most of them had a single or two-vessel coronary artery disease. Standard treatment strategies could be applied. The prognosis appeared to be excellent.

Adult↗
PubMed1998

Surgical closure of atrial septal defect. Minimally invasive cardiac surgery or median sternotomy?

BACKGROUND: Closure of ostium secundum atrial septal defect (ASD) vis median sternotomy (MS) is a simple procedure for most cardiac surgeons. Minimally invasive cardiac surgery (MICS) has recently been applied in the management of intracardiac lesions. METHODS: We report our experience in surgical closure of isolated ASD via MICS in 60 patients and via MS in 58 patients. There was no difference between these two groups in gender, age, body weight, ratio of systemic to pulmonary blood flow, and pulmonary arterial pressure. RESULTS: The duration of cardiopulmonary bypass was significantly longer in the MICS group than in the MS group [27 to 126 min (42 +/- 12) and 14 to 158 min (27 +/- 11), respectively; (p < 0.001]. However, the length of incision, incidence of temporary pacemaker wire insertion rate, duration of endotracheal intubation, timing of oral intake, postoperative day drainage amount, incidence of parenteral analgesic injection, postoperative length of stay, and return to normal activity interval were significant shorter and lower in patients of the MICS group than in those of the MS group. All the patients recovered rapidly from the surgery. Follow-up was complete in all patients, with no late complications and no residual shunt. CONCLUSION: Our results suggest that MICS is a good option for surgical closure of ASD.

Adolescent↗
PubMed1998

Minimal access surgical techniques in coronary artery bypass grafting for triple-vessel disease.

BACKGROUND: Minimal access surgical techniques in coronary artery bypass grafting have been used mainly in the management of single-vessel disease. METHODS: Fifteen patients, 11 men and 4 women with a mean age of 64.1 years (range, 35.7 to 78.0 years), underwent operation for triple-vessel disease using minimal access techniques. The procedures were performed through a limited left parasternal thoracotomy using femorofemoral extracorporeal circulation. The myocardium was protected by the antegrade infusion of cold blood cardioplegic solution while the aorta was cross-clamped. RESULTS: Under direct vision, the left saphenous vein grafts were connected sequentially to the diagonal branch, obtuse marginal branch, and posterior descending branch, and the left internal thoracic artery graft was anastomosed to the left anterior descending artery in each patient. The mean aortic cross-clamp time was 86 +/- 17 minutes (range, 67 to 125 minutes). The mean duration of extracorporeal circulation was 112 +/- 22 minutes (range, 82 to 162 minutes). The postoperative course was uneventful in all patients. Follow-up was complete in all patients at a mean of 7.4 months (range, 6.0 to 8.5 months), and there were no late deaths or angina. Coronary angiography in 8 patients showed patent grafts. CONCLUSIONS: Our experience demonstrates that minimal access surgical techniques in coronary artery bypass grafting are technically feasible and may be an alternative approach in the surgical revascularization of triple-vessel disease.

Adult↗
PubMed1998

The Gln-Arg 191 polymorphism of the human paraoxonase gene is not associated with the risk of coronary artery disease among Chinese in Taiwan.

Paraoxonase (PON1) is a high density lipoprotein-associated enzyme capable of hydrolyzing lipid peroxides, and thus, might protect lipoproteins from oxidation. A common polymorphism due to an amino acid substitution (Gln-Arg) at codon 191 is considered to be a major determinant of variation in serum PON1 activity. Recent studies have suggested that the PON1-191 polymorphism is an independent risk factor for coronary atherosclerosis in patients with or without diabetes mellitus. The association of PON1-191 polymorphism genotypes and coronary artery disease (CAD) among Chinese subjects in Taiwan was examined. The genotype of 218 angiographically documented CAD patients and the same number of age- and sex-matched control subjects was determined. Genotypes AA, AB and BB were present in 25 (11%), 102 (47%) and 91 (42%) of control subjects, respectively, and in 30 (14%), 96 (44%) and 92 (42%) of CAD patients, respectively (chi2 = 0.57, P = 0.75 between groups). The frequency of the A allele was 0.36 for the control group and 0.35 for CAD patients (P = 0.94). No significant differences in the PON1-191 genotype frequencies could be found between groups when multivariate logistic regression analysis was performed, or different subgroups of age, sex or risk factors were analyzed. Among control subjects, there was also no significant difference between genotypes of the PON1-191 polymorphism and various clinical and lipid variables. In conclusion, our data suggest that there is no association between the Gln-Arg 191 polymorphism of the human PON1 gene and CAD among Chinese subjects in Taiwan.

Alleles↗
PubMed1998

Primary pericardial mesothelioma with cardiac tamponade and distant metastasis: case report.

Although cardiac tamponade is a well-known complication of malignancy, it is uncommon as the initial manifestation. The antemortem diagnosis is difficult and distant metastasis is extremely rare. The presentations of primary pericardial mesothelioma are nonspecific. Pathologically, mesothelioma is the most common in primary tumors of the pericardium. Radical surgery can be used to treat a localized mesothelioma. However, the therapy for advanced primary pericardial mesothelioma is usually palliative because it is resistant to irradiation, and chemotherapy does not markedly improve the outcome. The prognosis is uniformly poor. The median survival from the onset of symptoms is 6 months. We present a 67-year-old woman with cardiac tamponade 4 months prior to a definitive diagnosis of primary pericardial mesothelioma. A computed tomogram confirmed multiple well-enhanced nodules in the pericardium, lungs and liver. Unfortunately, the patient died of multiple organ failure.

Aged↗
PubMed1998

Video-assisted cardiac surgery: preliminary results in Chang Gung Memorial Hospital.

OBJECTIVE: To summarize the experience of utilization of video-assisted endoscopy in 91 patients operated on at Chang Gung Memorial Hospital, Taipei, China. METHODS: From October 1995, through August 1996, 91 patients (44 male and 47 female) received video-assisted cardiac surgery (VACS). Their ages ranged from 1 year to 79.5 years (25.7 +/- 21.7). Indications for surgery were atrial septal defect (59 patients), ventricular septal defect (15), coronary artery disease (4), severe mitral regurgitation (4), severe tricuspid regurgitation (3), thrombosis of mitral mechanical prosthesis (3), left atrial tumor (2), and left ventricular thrombus with dilated cardiomyopathy (1). The VACS was performed through right or left anterior minithoracotomy and guided by video-assisted endoscopic techniques by means of projected images on the video monitor under extracorporeal circulation. The aorta was not cross-clamped and the myocardium was protected by continuous coronary perfusion with hypothermic fibrillatory arrest (rectal temperature 22.6 +/- 4.0 degrees C). Conventional instruments were used. RESULTS: All lesions were corrected successfully. The bypass time was 27 to 335 minutes (72.8 +/- 52.7). The operative time was 1.3 to 8.5 hours (3.0 +/- 1.7). There were no operative deaths and 3 late deaths. Follow-up was complete in all survivors (6 to 16 months, mean 8.7). Most of them were found to be in NYHA functional I or II. CONCLUSION: Our preliminary experiences demonstrate that VACS is simple and effective in surgical correction of selected cardiac lesions. Short-term results show good outcomes.

Adolescent↗
PubMed1998

Unusual coronary artery ectasia and stenosis in a patient with systemic lupus erythematosus and acute myocardial infarction.

Acute myocardial infarction is an important and sometimes fatal complication of systemic lupus erythematosus (SLE). We describe a case of acute myocardial infarction in a 23-year-old woman with SLE. Angiography revealed coronary ectasia in the left main and proximal circumflex coronary arteries, as well as a stenotic lesion in the left anterior descending artery. The possible pathophysiology is discussed.

Adult↗
PubMed1998

Transcatheter closure of atrial septal defect guided by on-line transesophageal echocardiography.

Transcatheter occlusion of secundum atrial septal defect has been tried since 1976. Some investigators have incorporated on-line transesophageal echocardiography so as to better monitor the procedure. Most, however, have used endotracheal intubation and general anesthesia. The aim of this study was to evaluate the feasibility of adjunct guidance using on-line transesophageal echocardiography without intubation and general anesthesia in adolescent or adult patients undergoing transcatheter occlusion of secundum atrial septal defects. Ten consecutive cases (age 15-68 years) of secundum atrial septal defects with a pulmonary to systemic flow ratio of > 1.5 and a balloon-stretched diameter of < or = 25 mm were enrolled in the study. The Sideris' buttoned devices were used. The procedure was guided by on-line transesophageal echocardiography and fluoroscopy. Endotracheal intubation and general anesthesia were not employed. The diameters of the atrial septal defects ranged from 6 to 19 mm as determined by transesophageal echocardiography, from 7 to 20 mm as determined by atrial angiography and from 11 to 25 mm as determined by balloon sizing. The Sideris' buttoned devices were successfully deployed in all the patients. On-line transesophageal echocardiography greatly facilitated balloon sizing, device development and immediate assessment. One device unbuttoned 24 hours after the procedure and was retrieved smoothly. The remaining 9 patients were followed-up for 12 months. Two patients had no shunt, 3 had a trivial (average diameter by transesophageal echocardiography = 1-3 mm) and 4 had a small (average diameter = 4-6 mm) residual shunt at the latest follow-up. The cardiothoracic ratios decreased from 0.52 +/- 0.06 to 0.48 +/- 0.06 (p = 0.0131). There was no mortality, stroke or device fracture during the follow-up period. Thus, transcatheter occlusion of secundum atrial septal defect under adjunct guidance using on-line transesophageal echocardiography without endotracheal intubation and general anesthesia is promising for selected patients.

Adolescent↗
PubMed1997

Angiotensinogen and angiotensin-I converting enzyme gene polymorphisms and the risk of coronary artery disease in Chinese.

The homozygous deletion allele (DD) of the angiotensin-I converting enzyme (ACE) gene and the T235 homozygote of the angiotensinogen (AGT) gene have been reported to be correlated with an increased prevalence of coronary artery disease (CAD) and myocardial infarction (MI). The importance of the DD genotype and T235 homozygote as genetic risk factors for CAD in Chinese remains uncertain. This study included 426 patients who underwent coronary angiography and 180 healthy subjects without clinical evidence of CAD. Coronary angiography identified 268 patients with CAD (CAD group) and 158 patients without CAD. The healthy subjects and patients without angiographic evidence of CAD constituted the control group. Three polymorphisms were studied: an insertion/deletion (I/D) polymorphism of the ACE gene and the T174 M and M235T polymorphisms of the AGT gene. No association was found between any of the three studied polymorphisms and the risk of CAD or MI in Chinese using univariate or multivariate analysis. In multivariate analysis, the relative risks were 1.20 (95% confidence interval = 0.91-1.61, P = 0.20) for the DD genotype, 1.05 (95% CI = 0.82-1.35, P = 0.69) for the T174 homozygote, and 1.19 (95% CI = 0.91-1.55, P = 0.20) for the T235 homozygote. Similarly, no significant difference was found in the frequencies of the DD genotype and the T174 and T235 homozygotes between the control group, the CAD group, the non-MI group, and the MI group when analyzed according to sex, age, or degree of risk. Our data suggest that neither the DD genotype of the ACE I/D polymorphism nor the T174 and T235 homozygotes of the AGT gene confer significant risk for CAD or MI in Chinese.

Angiotensinogen↗
PubMed1997

Interaction between obesity and genetic polymorphisms in the apolipoprotein CIII gene and lipoprotein lipase gene on the risk of hypertriglyceridemia in Chinese.

To understand the effects of the interaction between genetic polymorphisms and obesity on the risk of hypertriglyceridemia (HTG), two polymorphisms, an SstI polymorphism on the apolipoprotein CIII gene and a HindIII polymorphism on the lipoprotein lipase gene, were analyzed in 339 Chinese subjects with (82 cases in the HTG group) or without HTG (257 cases in the control group). Our data revealed that the frequencies of obesity, the SstI minor allele (S2), and the HindIII major allele (H+) in the HTG group were significantly higher than in the control group. Subgroup analysis revealed that the association between these two polymorphisms and HTG occurred predominantly in nonobese subjects and in subjects with the less hypertriglyceridemic genotype of another polymorphism. Multivariate logistic regression analysis showed that all three risk factors (obesity, S2-containing chromosome, and H+ homozygosity) were associated with HTG, and an interaction was found between obesity and H+ homozygosity for the occurrence of HTG. The risk of HTG increased significantly with combinations of risk factors. Subjects can be divided into low or high risk groups for HTG using such combinations. These results provide evidence of interaction between obesity and the HindIII polymorphism of the lipoprotein lipase gene on the risk of HTG.

Alleles↗