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W T Vigneswaran

Publications and source records attributed to W T Vigneswaran.

16 recordsLinked to original sources

Ventricular remodeling after orthotopic cardiac transplantation.

OBJECTIVE: To determine quantitative changes in ventricular chamber volumes and left ventricular mass after orthotopic cardiac transplantation. MATERIAL AND METHODS: Right ventricular and left ventricular chamber volumes and left ventricular muscle mass were quantified by electron beam computed tomography in 10 patients at 1 month and 12 months after orthotopic cardiac transplantation. RESULTS: During the study period, the mean right ventricular end-diastolic volumes increased from 117 +/- 26.1 cc to 143 +/- 25.3 cc (P < 0.005), and the mean left ventricular end-diastolic volumes increased from 90 +/- 20.6 cc to 117 +/- 27.3 cc (P < 0.001). Left ventricular stroke volume increased from 63 +/- 16.5 cc at 1 month to 78 +/- 19.8 cc by 12 months (P < 0.005). These changes were associated with a concurrent reduction in global left ventricular muscle mass from 168 +/- 25.2 g to 145 +/- 16.3 g (P < 0.01). The left ventricular end-diastolic volume/mass ratio, an index of wall tension, was abnormally low at 1 month but was in the normal range by 12 months (P < 0.0005). Both left ventricular and right ventricular ejection fractions were normal at all times and not significantly changed between the 1-month and 12-month studies. CONCLUSION: Significant right and left ventricular remodeling occurs between 1 month and 12 months after orthotopic cardiac transplantation, with progressive cavity dilatation but reduction in global left ventricular muscle mass. These adjustments, especially in the left ventricle, tend to reduce the volume/mass ratio by 1 year and are compatible with normalization of ventricular wall tension between the early and late scan dates. Routine clinical measurements of ejection fraction alone mask the almost parallel increases in stroke volume and end-diastolic volume during the first 12 months after orthotopic cardiac transplantation.

Adult

Extended esophagectomy in the management of carcinoma of the upper thoracic esophagus.

Upper thoracic esophageal tumors adjacent to the trachea often require a preliminary thoracotomy to accomplish resection. Between January 1985 and July 1992, 49 consecutive patients (38 men and 11 women) underwent extended esophagectomy for esophageal cancer where the neoplasm was mobilized through an initial right thoracotomy and then resected and reconstructed through an abdomino-cervical approach. Ages ranged from 40 to 80 years (median 63.4 years). The tumor was located in the upper third of the thoracic esophagus in 44 patients and in the middle third in five. Thirty-three patients had squamous cell carcinoma, 14 had adenocarcinoma, and two had adenosquamous cell carcinoma. Complications occurred in 35 patients (71.4%) and included anastomotic leak in 15, vocal cord paralysis in 11, atrial arrhythmia in nine, pneumonia in six, wound infection in five, and postoperative bleeding in one. Three patients required tracheostomy. There was one postoperative death (2.0%). Median survival was 0.9 years (range 1 month to 5.1 years). Thirty-one patients were alive at the time this article was written, 28 without evidence of cancer. Cause of death was recurrent disease in 13 patients, unrelated to cancer in three, and unknown in one. Overall actuarial 3- and 5-year survivals were 48.6% and 18.2%, respectively. Four-year survival for stage II disease was 44.6% as compared to 24.9% for stage III (p < 0.02). The presence of lymph node metastases significantly affected survival. Three-year survival for patients with N0 disease was 77.9% compared with 20.9% for patients with N1 disease (p < 0.01). Age, sex, and cell type had no effect on survival. Ten patients had late dysphagia, four had gastroesophageal reflux, and one had dumping symptoms. Although associated with significant morbidity, we conclude that extended esophagectomy is an acceptable method of management for tumors of the upper thoracic esophagus. Mortality is low, and long-term results are reasonable.

Adenocarcinoma

Transhiatal esophagectomy for carcinoma of the esophagus.

One hundred thirty-one patients (107 men and 24 women) underwent transhiatal esophagectomy for carcinoma of the esophagus. Median age was 65.3 years (range, 30 to 89 years). Signs and symptoms were present in 130 patients, which included dysphagia in 96 (73.3%) and weight loss (median, 7.7 kg) in 52 (39.7%). The cancer involved the gastroesophageal junction in 94 patients, the lower half of the intrathoracic esophagus in 25, the upper half in 10, and multiple sites in 2. An adenocarcinoma was present in 101 patients (77.1%), squamous cell carcinoma in 29 (22.1%), and adenosquamous cell in 1 (0.8%). The cancer was classified as stage 0 in 4 patients, stage I in 16, stage IIA in 26, stage IIB in 18, stage III in 65, and stage IV in 1. The stomach was used to replace the esophagus in all patients. Operative mortality was 2.3%. Anastomotic leak developed in 32 patients; 6 leaks were not clinically significant, 12 healed with drainage alone, and 14 required further surgical intervention. Follow-up ranged from 1 month to 6.7 years (median, 1.4 years). Currently, 42 patients are alive, 34 without evidence of recurrence. Overall 5-year survival was 20.8% and varied according to stage. Five-year survival was 47.5% for patients with stage I disease compared with 37.7% for patients in stage II and only 5.8% 4-year survival for patients in stage III. Cell type also influenced survival. Five-year survival for patients with adenocarcinoma was 27.1% compared with zero for patients with squamous cell carcinoma (p < 0.03).(ABSTRACT TRUNCATED AT 250 WORDS)

Adenocarcinoma

Right ventricular assessment in patients presenting for lung transplantation.

Chronic pulmonary disease is associated with varying degrees of cardiac dysfunction. Because of the potentially predominant effect of severe lung disease on right ventricular (RV) size and function, a reliable method to assess RV mechanics before and after lung transplantation may provide information of long-term significance and/or prognosis. Conventional invasive and non-invasive imaging methods have a number of limitations in evaluating RV function. Ultrafast computed tomographic (ultrafast CT) scanning has been shown to provide quantitative assessment of RV and left ventricular (LV) function in individuals with and without cardiac disease. Twenty-two patients presenting during evaluation for possible lung transplantation with end-stage pulmonary disease formed the basis of this study. There were 14 patients with chronic obstructive pulmonary disease and 8 with pulmonary fibrosis. Conventional transthoracic echocardiography and ultrafast CT were used for the assessment of RV and LV function. All patients had invasive assessment of right-sided hemodynamics and pulmonary function studies performed within 7-10 days of cardiac imaging. A qualitative assessment of RV size or function was possible in all but two patients by echocardiogram, but in 45%, the echocardiographic examination was described as suboptimal. In contrast, a quantitative assessment of ventricular volumes and systolic function was obtained in all patients by ultrafast CT. Pulmonary function parameters or hemodynamic measurements obtained during cardiac catheterization did not correlate with any assessment of RV function. We concluded that (1) ultrafast CT provides measurement of the RV and LV cavity dimension and systolic function; (2) invasive right-sided hemodynamics or pulmonary function studies do not predict RV function; and (3) echocardiography does not uniformly provide assessment of RV function in patients with chronic pulmonary disease.

Adult

Disease of the left main coronary artery: early surgical results and their association with carotid artery stenosis.

OBJECTIVES: To review the results of surgical revascularisation for left main coronary artery stenosis and the associated vascular pathology that is responsible for cerebrovascular complication. PATIENTS: 60 patients (45 men, 15 women) (mean age 61.3 (39-79)) who underwent revascularisation for stenosis of the left main stem coronary artery (LMS) between January 1987 and August 1990 were compared with an age and sex matched control group of patients undergoing revascularisation for triple vessel disease during the same period. OUTCOME MEASURES: In-hospital morbidity and operative mortality. RESULTS: 24 patients in the LMS group presented with unstable angina. The left ventricular ejection fraction was less than 50% in 30 patients and less than 30% in nine. 17 patients (28%) had large vessel extracranial carotid artery disease and 10 patients had vascular disease of the lower limbs. In six patients atheromatous plaques were noted in the ascending aorta during surgery. There was no in-hospital mortality. In-hospital morbidity included neurological deficits in five (8.3%), arrhythmias in seven (11.6%), and pulmonary complications in six (10%) patients. The incidence of carotid artery disease in the LMS group was significantly higher (p = 0.04). Atheromatous plaque in the ascending aorta and postoperative neurological complications were more common patients with LMS. CONCLUSIONS: The incidence of carotid artery disease was higher and postoperative cerebrovascular complications were more common in patients who had coronary artery revascularisation for stenosis of the left main stem coronary artery. The early surgical results were excellent. These findings suggest that for optimum perioperative management patients with stenosis of the left main coronary artery should be screened for carotid artery disease before bypass surgery.

Adult

Surgery for bullous disease of the lung.

Between July 1986 and December 1990, 22 patients underwent 23 operative procedures for bullous disease at Harefield Hospital. Their ages ranged from 21 to 71 years (mean 49.8 years). There were 18 males and 4 females. All patients were operated upon for symptoms of exertional dyspnoea. Four patients belonged to functional class IV, 11 to class III and 3 to class II. In 80% of patients, computed tomography was performed as part of the preoperative assessment. The bullae were dealt with in 13 patients on the right side, in 7 on the left and in 2 bilaterally. Six patients were treated by a modified Monaldi procedure and 17 by bullectomy. There was no operative mortality. Mean hospital stay was 14.8 days. Two patients required a second operative procedure during their hospital stay for persistent air leak and pneumothorax. One of these had a Monaldi procedure in the first instance but underwent bullectomy later. All patients improved symptomatically, 10 patients moving up two grades and 12, one grade. Mean FEV1, FVC and MVV were significantly improved postoperatively, but there were no significant changes in RV or TLC. A graduated exercise test was performed in 4 patients. Improvements were seen in ventilation and oxygen consumption at anaerobic threshold and maximum exercise. Surgery for bullous disease improves symptoms by reducing airway obstruction and increasing ventilatory capacity on exercise.

Adult

Primary pericardial mesothelioma presenting as tuberculous pericarditis.

Ante-mortem diagnosis of primary pericardial mesothelioma is very rare. We report a case which presented clinically as tuberculous constrictive pericarditis. The patient underwent pericardial resection with an immediate haemodynamic benefit, although the malignant process progressed, and he died 14 weeks later.

Adult

Evolution of the management of anomalous left coronary artery: a new surgical approach.

Twelve patients with anomalous left coronary artery (LCA) from the pulmonary artery were treated surgically. Mean age was 13 months and mean weight, 7.7 kg. One of the following techniques was used in 8 patients: suture obliteration of the coronary orifice, ligation of the anomalous LCA and grafting of the internal mammary artery to the distal LCA, aortic reimplantation of the anomalous LCA, creation of an aortopulmonary window, and direct anastomosis to the right subclavian artery. In 4 patients, a new technique to establish a two-coronary artery system involved tube extension of the anomalous LCA with pulmonary artery wall and then anastomosis to the right subclavian artery using cardiopulmonary by-pass without aortic cross-clamping. There were two hospital deaths (17%) and one late death. The condition of the 9 long-term survivors was improved at late follow-up. Postoperative assessment showed smaller Q wave on the electrocardiogram, reduced cardiac size, and good left ventricular function. All patients in whom the repair was done using the new technique were free from postoperative cardiac complications, had shortened hospital stays, and were alive with a patent two-coronary artery system at late follow-up. We believe this approach is a safer method for establishing a two-coronary artery system in infants and small children with an anomalous LCA arising from the pulmonary artery.

Cardiopulmonary Bypass

5-Hydroxytryptamine uptake in oxygen radical-mediated acute lung injury.

Pulmonary endothelial cell function (ECF) studies have been shown to be a sensitive indicator of chronic lung injury. We attempted to correlate changes in 5-hydroxytryptamine (5HT) uptake with an acute oxygen radical-mediated lung injury in dogs. Beta-d glucose/glucose oxidase was injected intravenously in an experimental group (n = 10), while the control group (n = 5) received saline. 5HT uptake, measured using a multiple indicator dilution technique before and 20 min after injection, was calculated for both the percent total uptake and the peak extraction ratio of 5HT during a single passage through the lung. The mean pulmonary and systemic arterial pressures (PAP, SAP), total pulmonary resistance (TPR), extravascular lung water (EVLW), and wet-to-dry weight ratios were also determined. The experimental group showed an acute rise in PAP and TPR and a fall in SAP after the injection, all returning to normal by 20 min; total 5HT uptake fell from 81 +/- 2.3% to 47 +/- 6.5% (p = 0.0002) as did the peak extraction ratio from 0.87 +/- 0.013 to 0.44 +/- 0.066 (p = 0.0001). No change in 5HT uptake was observed in the control group. EVLW did not change in either group, but wet-to-dry weight ratio was elevated in the experimental group (5.21 +/- 0.12 versus 4.73 +/- 0.06, p less than 0.01). ECF studies of 5HT uptake appear to be a sensitive indicator of acute lung injury in this large-animal, oxygen radical-induced injury model.

Acute Disease

Intra-aortic balloon pumping: seven years' experience.

The indications for intra-aortic balloon pumping vary widely from country to country and from one cardiac surgical unit to another. Its use in Glasgow from 1976 to 1983 in 63 patients has been reviewed. Six of the patients (9.5%) had the intra-aortic balloon inserted before cardiac surgery, 43 (68.2%) at the time of surgery, and 14 (22.2%) in the postoperative period. Of the 63 patients, 11 could not be weaned from cardiopulmonary bypass despite intra-aortic balloon pumping, and died in the operating room. A further 35 patients had intra-aortic balloon pumping but died in the immediate postoperative period. Seventeen patients (27%) survived from six weeks to 3.3 years after receiving the support of intra-aortic balloon pumping. There was major morbidity in 11 patients (17%), all of whom developed degrees of ischaemia due to ileofemoral arterial obstruction in the leg in which the balloon was inserted. The conservative use of the method in this centre is reflected in the high mortality of these patients.

Adult

Pericardectomy.

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Adolescent

Management of pulmonary metastases from colorectal cancer.

A significant number of patients who undergo complete resection of colorectal carcinoma develop pulmonary metastases. Despite advances in systemic chemotherapy, resection of the metastases localized to lungs remains the only mode of curative treatment. Control of primary disease, ability to resect all gross tumor, and adequate cardiorespiratory reserve are significant factors in selecting patients for resection. Hepatic metastases do not appear to influence long-term survival if completely resected. Patients with solitary metastases experienced the best long-term survival, but patients with as many as three pulmonary metastases, either unilateral or bilateral, could undergo resection with a 40% 5-year survival. The number of nodules does not constitute absolute criteria by which to select patients, and the decision must be individualized, given the set of circumstances. Complete surgical resection is critical to achieving long-term survival and is best achieved by a median sternotomy or "clamshell" incision. Resection of the metastases can be more effectively accomplished in most instances by wedge excision than by lobectomy or pneumonectomy, with minimal operative mortality and morbidity.

Antineoplastic Agents