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L Sharples

Publications and source records attributed to L Sharples.

12 recordsLinked to original sources
PubMed1992

Coronary occlusive disease and late graft failure after cardiac transplantation.

OBJECTIVE: Coronary occlusive disease is the main cause of late mortality after cardiac transplantation. It has both similarities and differences compared with conventional atherosclerotic coronary disease. The pathophysiology of late graft failure from coronary occlusive disease is unclear at present. We reviewed the experience of this disorder in our cardiac transplant programme. DESIGN: A retrospective analysis of angiographic and pathological data. SETTING: A regional cardiothoracic centre and transplant unit. PATIENTS: Of a population of 383 orthotopic cardiac transplant recipients operated upon between January 1979 and June 1990, 447 coronary angiograms were available for review in 193 patients. Thirteen of a possible 18 results of post mortem examinations from patients dying from coronary occlusive disease were available. MAIN OUTCOME MEASURE: Coronary occlusive disease was defined as any evidence of disease on coronary angiography. Post mortem examinations were performed with standard techniques. RESULTS: The angiographic prevalence of coronary occlusive disease was 3% (1/32 patients) and 40% (19/47 patients) at one and five years respectively. Twenty six grafts failed due to coronary occlusive disease compared with 132 graft failures from all causes during this period. Acute thrombosis was present in a large vessel in seven of 13 fatal cases undergoing necropsy (54%). Noticeable large vessel involvement with disease in smaller distal vessels was present in four patients (31%). The remaining two patients (15%) had small vessel disease alone. Twelve of the 13 patients had significant cardiomegaly (cardiac weight > or = 400 g) with a mean weight of 510 (range 370-740) g. CONCLUSION: Coronary occlusive disease is the main late complication after cardiac transplantation. A combination of coronary thrombosis, ischaemia from stenoses of large and small coronary vessels, and cardiomegaly contribute to the graft failure of these patients.

Adolescent↗
PubMed1992

Impairment of coronary flow reserve in orthotopic cardiac transplant recipients with minor coronary occlusive disease.

OBJECTIVE: Coronary occlusive disease is the major long-term complication after cardiac transplantation. The relation between minor angiographic abnormalities and myocardial perfusion has not been previously assessed in a large number of cardiac transplant patients. DESIGN: Prospective study. Coronary flow reserve was measured with an intracoronary Doppler flow probe in the proximal left anterior descending coronary artery in each patient. A dose of intracoronary papaverine producing maximal vasodilation was then administered. SETTING: A regional cardiothoracic centre and a supraregional transplant unit. PATIENTS: Seven patients with chest pain but normal coronary anatomy (controls), and 61 cardiac transplant patients between three months and 10 years after operation (median 4.5 years). Twenty one cardiac transplant patients had angiographic evidence of minor coronary occlusive disease (mean (SD) percentage stenosis diameter 23% (6%)) in a primary or secondary coronary vessel (group 1), with 12 of these in the left anterior descending coronary artery (stenosis diameter (mean (SD) 24% (8%)). The remaining 40 transplant patients had normal coronary angiograms (group 2). MAIN OUTCOME MEASURE: Coronary flow reserve was defined as the ratio of the peak flow velocity after papaverine to the resting flow velocity. RESULTS: Group 1 patients had a noticeably impaired coronary flow reserve (2.6 (1.1)) compared with control patients (3.9 (0.4), p = 0.05) and, after adjusting for year after operation, compared with group 2 patients (3.8 (1.0), p < 0.001). No other variables were associated with a reduction in coronary flow reserve. Mean resting flow velocity was similar in all three groups (controls, 7.4 (4.6) cm/s; group 1, 7.5 (5.9) cm/s; and group 2, 7.3 (3.9) cm/s). Mean peak flow velocity response to papaverine was reduced in group 1 patients (18.1 (13.5) cm/s) relative to group 2 patients (27.5 (15.4) cm/s, p = 0.05) but not controls (28.4 (15.1) cm/s, p = 0.1). CONCLUSIONS: Coronary flow reserve and the peak flow response to the coronary vascular smooth muscle relaxant papaverine are impaired in cardiac transplant patients with minor coronary occlusive disease. This disturbance of cardiac microvascular function may contribute to the late morbidity and mortality seen in cardiac transplant patients with coronary occlusive disease.

Blood Flow Velocity↗
PubMed1992

Hemodynamic evaluation of the Monostrut and spherical disc Björk-Shiley aortic valve prosthesis with Doppler echocardiography.

A Doppler echocardiographic study was performed to assess whether the Monostrut model of the Björk-Shiley valve (Shiley, Inc., Irvine, Calif.) had an improved hemodynamic performance in comparison with the spherical disc model in the aortic position. Twenty retrospectively randomly selected patients were studied, 10 with each valve type. Within each valve type two sizes of valve were studied, 21 and 23 mm. The two groups were comparable with respect to age, postoperative time, fractional shortening, New York Heart Association functional class preoperatively, and body surface area. Pulsed and continuous wave Doppler measurements were recorded at rest. Continuous wave Doppler recordings were performed every 2 minutes after exercise with supine bicycle ergometry until 10 minutes after exercise. Peak and mean gradients across the aortic valve prostheses were estimated. Both groups achieved a significant and comparable rise in heart rate with exercise. The mean gradients +/- standard error of the mean at rest and 2 minutes after exercise were 19.7 +/- 1.9 mm Hg and 30.9 +/- 2.2 mm Hg, respectively in the spherical disc group compared with 14.9 +/- 1.1 mm Hg and 23.6 +/- 1.7 mm Hg in the Monostrut group (p < 0.05 and p < 0.025, respectively). Peak transvalvular gradient at rest was 30.7 +/- 2.7 mm Hg in the spherical group compared with 23.9 +/- 1.9 mm Hg in the Monostrut group (p < 0.05). We conclude that the Monostrut Björk-Shiley valve prosthesis has better hemodynamic performance than the spherical disc model in the aortic position.

Aortic Valve↗
PubMed1991

Risk factors for obliterative bronchiolitis in heart-lung transplant recipients.

Obliterative bronchiolitis is the major cause of death of long-term survivors of heart-lung transplantation. Of our first 75 patients who have received heart-lung transplantation, 38 have been followed for a year or longer. Eight patients developed clinical evidence of obliterative bronchiolitis within 15 months of transplantation, of whom four died with postmortem confirmation of extensive obliterative bronchiolitis, interstitial and pleural fibrosis, and vascular sclerosis in the heart and lungs. One further patient died before one year after chronic rejection. All nine patients had evidence on transbronchial biopsy of submucosal fibrosis and vascular sclerosis. Twelve of our remaining patients have shown similar areas of lung fibrosis on transbronchial biopsy, and the other eighteen are well and without fibrosis on transbronchial biopsy. Studies of the 274 biopsies obtained from 38 patients confirmed rejection on 182 occasions with more frequent, more persistent, and more severe rejection in the chronic rejection group than in the without-fibrosis or lung fibrosis groups. Opportunistic infection resulted in pneumonia on 19 occasions, and were most commonly found in lung fibrosis patients. We conclude that obliterative bronchiolitis is the likely outcome in patients with early, poorly controlled, severe rejection.

Adult↗
PubMed1991

Heart and lung transplantation for terminal cystic fibrosis. A 4 1/2-year experience.

From among 112 patients with cystic fibrosis who were assessed for heart-lung transplantation, 83 were accepted. Twenty-six died while awaiting heart-lung transplantation and 32 had the operation. The management and the outcome of these 32 patients is reported. Survival, infection, and rejection rates among these patients were compared with those of 61 patients without cystic fibrosis who underwent heart-lung transplantation between 1984 and 1990. The cumulative survival rate was 72.29% +/- 94.91% at 1 year and 55.59% +/- 7.50% at 3 years. The mortality rate was slightly higher in the group with cystic fibrosis during the first year after the operation but it was lower at 3 years. The difference, however, could have been due to chance alone (p = 0.308). The same was true for the prevalence of rejection (up to 6 months: chi 2 = 1.8141, p = 0.17), and infection (up to 6 months: chi 2 = 2.20, p = 0.14), between the two groups. It is concluded that cystic fibrosis does not constitute an additional risk in terms of survival and morbidity after heart-lung transplantation.

Adolescent↗
PubMed1990

The epidermal growth factor receptor and the prognosis of bladder cancer.

Epidermal growth factor is found in high concentrations in urine, and its receptor (EGFr) has been identified in certain bladder tumors. This study was performed to determine whether receptor positivity in the tumor was associated with a poor clinical outcome. One hundred one patients with newly diagnosed bladder cancer were studied prospectively by immunohistochemical staining for the EGFr. There were 76 men and 25 women, with a mean follow-up of 30 months; 49 had tumors invading muscle: 18 were pTl (tumor invading lamina propia) and 34 were pTa (tumor confined to urothelium). Strong staining for the EGFr was found in 48% of tumors and was associated with high stage (P less than 0.001). Death of bladder cancer (40 of 101) was associated independently with high stage (P less than 0.0001) and EGFr positivity (P less than 0.001). In patients with pTa and pTl tumors, EGFr positivity was associated with multiplicity (P less than 0.01), time to recurrence (P less than 0.03), and recurrence rate (P less than 0.004). Tumor progression was associated with EGFr positivity (P less than 0.0001) and multiplicity (P less than 0.05). EGFr were found on a significant proportion of bladder tumors: such tumors were more likely to result in death, recurrence, and progression.

Aged↗
PubMed1990

Cystic fibrosis: a new challenge for cardiothoracic surgery.

Cystic fibrosis (CF) is the most common fatal inherited disease in caucasian populations. Between 80-120 CF patients die each year in England and Wales, the majority from pulmonary disease. Since October 1985, 17 patients with CF have undergone heart-lung transplantation (HLT) at our institution. Only 3 early deaths have occurred in the first 2 postoperative months. Another patient died 9 months after transplantation. Thirteen patients are now alive 1-46 months (mean 14 month) post transplantation. Actuarial survival at 6 months is 80% for CF patients compared to 73% for non-CF patients. Both groups of patients have similar profiles of rejection and infection. In the Caucasian population, CF patients form the largest potential recipient group for HLT and our experience suggests that those CF patients who undergo HLT have a favourable outcome.

Actuarial Analysis↗
PubMedDate not supplied

Donor heart preservation survey.

A questionnaire requesting information on donor heart preservation technique and outcomes during the first 6 months of 1990 was circulated to heart transplantation centers worldwide. Seventy-nine usable replies representing 1371 clinical transplant operations were received. Twenty-seven percent of the respondents reported using some form of donor pretreatment. Most (90%) used single flush cardioplegic induction with the use of eight different types of cardioplegic solutions, only 5% of which were oxygenated. Six different types of storage media were used, and the coolant was melting ice in 66% of the centers. Storage temperatures between 0 degrees C and 7 degrees C were reported, with 78% of the respondents using 4 degrees C storage. Fifty-five percent of the centers used some form of reperfusion modification. No statistically significant associations were noted between outcome and technique, apart from the use of storage medium in which the use of cardioplegic solution conferred a 2.5 times increase in deaths compared with cold saline. The results of this questionnaire provide evidence for the diversity of techniques currently used for donor heart preservation, reflecting the lack of any one optimal method.

Cardioplegic Solutions↗
PubMedDate not supplied

Some prognostic factors for the development of transplant-related coronary artery disease in human cardiac allografts.

The study of endomyocardial biopsy specimens taken in the first 130 days after transplantation has yielded no histologic features predictive of later development of transplant-related coronary artery disease. This study, however, indicated that a combination of the following factors might be predictive in cyclosporine-treated patients: untreated histologically proven episodes of rejection, infection with cytomegalovirus or reactivation of infection, ischemic heart disease in the recipient as the reason for heart transplantation, and possibly HLA-B5 or -B8 mismatch.

Adult↗