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S W K Cheng

Publications and source records attributed to S W K Cheng.

8 recordsLinked to original sources
PubMed2005

Detection of C. pneumoniae by polymerase chain reaction-enzyme immunoassay in abdominal aortic aneurysm walls and its association with rupture.

OBJECTIVE: Serological studies have suggested that one of the risk factors for aneurysm development is C. pneumoniae infection. The purpose of this study was to evaluate whether there is an association between the presence of C. pneumoniae DNA in aneurysms and ruptured abdominal aortic aneurysms. METHODS: Aortic walls were collected consecutively from 30 patients with intact AAA, 16 patients with ruptured AAA and 19 healthy organ donors (control). Purified DNAs from all aortas were analyzed for the presence of C. pneumoniae DNA in parallel by polymerase chain reaction-enzyme immunoassay (PCR-EIA) and agarose gel electrophoresis. PCR-EIA has a high sensitivity in detecting low DNA copy number in clinical atherosclerotic samples. RESULTS: C. pneumoniae DNA was detected more frequently in patients with aneurysms, particular with ruptured aneurysms. The incidence of positive C. pneumoniae DNA was 73.3% in intact AAA and 10.5% in control aortas, with the highest frequency in ruptured AAA (100%) (p < 0.05). CONCLUSION: Giving the high specificity and sensitivity of PCR-EIA, these findings support the association of C. pneumoniae in the pathogenesis of aneurysm development, growth and rupture.

Aged↗
PubMed2004

Epidemiology of venous thromboembolism in a Chinese population.

BACKGROUND: Deep vein thrombosis (DVT) is uncommon in Asians and routine thromboprophylaxis for surgery is controversial. Despite recent reports of higher incidences in some Asian countries, population-based data are lacking. METHODS: Information from 2000 to 2001 was retrieved from a centralized computer public healthcare database serving an ethnic Chinese population of 6.7 million. The incidence, demographics and hospital mortality rates of DVT and pulmonary embolism (PE) were obtained, and analysed for different surgical categories. RESULTS: The overall annual incidences of DVT and PE were 17.1 and 3.9 per 100000 population respectively. Venous thromboembolic disease was more common with increasing age in both sexes. The annual age-specific incidences of DVT and PE were 81.1 and 18.6 per 100000 for those aged 65 years and over. Hospital mortality rates associated with DVT and PE were 7.3 and 23.8 per cent respectively. Among 120940 surgical operations a year, the mean incidence of postoperative DVT and PE was only 0.13 and 0.04 per cent respectively. No high-risk surgical group was identified. CONCLUSION: Venous thromboembolism is not as common in Chinese as in Caucasians, but it is certainly not rare. The majority of DVTs and PEs, however, were not associated with surgery, so routine thromboprophylaxis may not be required.

Adolescent↗
PubMed2004

Laparoscopic transperitoneal clipping of the inferior mesenteric artery for the management of type II endoleak after endovascular repair of an aneurysm.

We report the case of a high risk patient with an abdominal infrarenal aortic aneurysm (AAA) who was treated by endovascular technique and the subsequent management of a type II endoleak by the laparoscopic approach. In this case, a 74-year-old woman with a 6-cm infrarenal AAA underwent endovascular repair using a bifurcated stent-graft device. Surveillance CT scan showed a persistent type II endoleak at 1 week and 3 months after the operation. Angiography confirmed retrograde flow from the inferior mesenteric artery (IMA). Attempted transarterial embolization of the IMA via the superior mesenteric artery was not successful. Laparoscopic transperitoneal IMA clipping was performed. Subsequent aortic duplex scan and CT scan confirmed complete elimination of the type II endoleak. We conclude that a combination of endovascular and laparoscopic procedures can be used to manage AAA successfully.

Aged↗
PubMed2003

Clinical outcomes and changes in venous hemodynamics after subfascial endoscopic perforating vein surgery.

BACKGROUND: We evaluated the clinical results of subfascial endoscopic perforating vein surgery (SEPS) in patients with severe chronic venous insufficiency (CVI) (clinical class 4-6) and assessed the hemodynamic changes associated with SEPS using air plethysmography (APG). METHODS: Forty-five patients with severe CVI who had undergone SEPS were evaluated. Clinical score and venous hemodynamics, as measured by APG before operation and at 1 month and 1 year after operation, were compared using the Wilcoxon signed rank test. Patient satisfaction (on a visual analogue scale of 0 to 100%) was also assessed. RESULTS: There were 29 men and 16 women; their mean age was 60 years (range, 37-83). Thirty-five patients (78%) had active venous ulcers; the ulcers' mean size was 7.8 +/- 11.9 cm2 and the mean duration of ulceration was 9 +/- 10 months. There were no hospital deaths. Postoperative complications were uncommon (one groin wound infection and one case of thrombophlebitis). At a mean follow-up of 15 +/- 9 months, 34 ulcers (97%) had healed. The cumulative ulcer healing was 82% at 3 months. There were five recurrent ulcers (15%). Significant improvement was seen in the clinical scores (10 +/- 3 before operation, 6 +/- 4 at 1 month, and 4 +/- 3 at 1 year after operation). The venous filling index was also significantly improved after operation; this improvement was maintained at 1-year follow-up (7.36 +/- 6.23 ml/sec before operation, 3.63 +/- 3.90 ml/sec at 1 month, and 3.14 +/- 2.06 ml/sec at 1 year). The degree of patient satisfaction was also remarkable, with 74 +/- 17% and 90 +/- 12% satisfaction at 1-month and 1-year follow-up, respectively. CONCLUSIONS: SEPS is a safe and effective treatment for patients with severe CVI. It leads to hemodynamic improvement, with rapid ulcer healing, and it is associated with a high degree of patient satisfaction.

Adult↗
PubMed2003

Carotid stenting for irradiation-associated carotid stenosis 3 years after previous carotid endarterectomy.

Extracranial carotid stenosis is a known complication of external irradiation to the head and neck region. We report on a patient with previous carotid endarterectomy for irradiation-associated carotid stenosis. This patient developed symptomatic carotid stenosis over the ipsilateral common carotid artery proximal to the previous endarterectomy site 3 years later, and was successfully treated with carotid angioplasty and stenting. This case illustrates the importance of Duplex scan surveillance after carotid endarterectomy for patients with irradiation-associated carotid stenosis. The complimentary role of carotid endarterectomy and carotid angioplasty for managing such a patient is highlighted.

Angioplasty, Balloon↗
PubMed2002

Diagnosing deep vein thrombosis in the lower extremity: correlation of clinical and duplex scan findings.

OBJECTIVE: To identify factors that predict a positive duplex scan examination result in patients with suspected deep vein thrombosis of the lower extremity. DESIGN: Retrospective study. SETTING: Vascular laboratory in a university teaching hospital. PATIENTS AND METHODS: The results of 345 lower extremity duplex venous scans performed between August 1994 and November 1998 were reviewed. All patients were in-patients referred from different specialties due to clinical suspicion of lower extremity deep vein thrombosis. Positive duplex scans were correlated with patients' demographic data (sex, age), medical history (history of malignancy, deep vein thrombosis, and pulmonary embolism) and clinical features (leg swelling, venous insufficiency, calf pain, and leg ulcer). Univariate analysis was performed using the Chi squared test. RESULTS: A total of 345 scans were performed for 313 patients. The mean age was 55 years (range, 19-92 years). Sixty-three patients (49 male, 14 female) had a positive scan, giving a yield of 18.3%. Four factors had a significant association with a positive scan: male sex (P=0.0102), history of malignancy (P=0.0040), history of deep vein thrombosis (P=0.0001), and history of pulmonary embolism (P=0.0265). CONCLUSIONS: Common presenting clinical features do not predict the result of ultrasonographic investigation for deep vein thrombosis. The chance of having a positive scan is significantly higher in male patients and those with a history of malignancy, deep vein thrombosis, or pulmonary embolism.

Adult↗
PubMed2002

Treatment of a ruptured iliac aneurysm with an endoluminal stent graft.

The management of a 79-year-old man presenting with a ruptured common iliac aneurysm is described. The patient had multiple medical problems including hypertension, ischaemic heart disease, and atrial fibrillation, as well as a left hemispheric stroke 5 years previously. Traditional open surgery was judged unsuitable in this case because of the predicted poor outcome. The patient was subsequently treated successfully with endoluminal stent grafting.

Aged↗