Andrew Murday

Resternotomy for bleeding after cardiac operation: A marker for increased morbidity and mortality

Over a 2-year period from January 1, 1992, to December 31, 1993, of 2,221 patients undergoing cardiac operations in our unit, 85 (3.8%) were reopened for the control of bleeding (9 patients more than once). The incidence of resternotomy in coronary cases was 2.3%, but resternotomy was more than three times as likely in valve cases (odds ratio, 3.4; 95% confidence interval, 2.1 to 5.4). Previous cardiac operation was more common among resternotomy patients than among the remainder (18% versus 9%, respectively; p = 0.018). An identifiable source of bleeding was found in 57 of the 85 patients (67%), but a concurrent coagulopathy was common (45 patients). Resternotomy patients, as a group, had higher preoperative risk scores (Parsonnet) than did the other patients (p < 0.0001), stayed longer in the intensive care unit (p < 0.0001), and had greater requirements for intraaortic balloon counterpulsation (14% versus 3%) and hemofiltration (9% versus 3%) (p < 0.0001 and p < 0.01, respectively). Nineteen resternotomy patients (22%) died in the hospital, a proportion significantly greater than the risk assigned to this group of patients preoperatively (12.8%) (p = 0.008). In contrast, the observed mortality for the other 2,136 patients (5.5%) was significantly less (8.3%) (p < 0.00006). Multiple forward stepwise logistic-regression analysis confirmed resternotomy for excessive bleeding after cardiac operation to be a significant independent predictor of a prolonged stay in the intensive care unit (p < 0.0001), the need for intraaortic balloon counterpulsation (p < 0.0001), and death (p < 0.0001).

Slide tracheoplasty for congenital funnel-shaped tracheal stenosis

Congenital funnel-shaped trachea is a serious condition, and the survival rate in infants is poor. A slide tracheoplasty is described, with a brief review of other methods of repair. Two cases that demonstrate the operability of congenital funnel-shaped trachea in infancy are reported.

Effect of receiving a heart transplant: analysis of a national cohort entered on to a waiting list, stratified by heart failure severity

Abstract Objective: To determine whether there is a survival benefit associated with cardiac transplantation in Germany. Design: Prospective observational cohort study. Setting: All 889 adult patients listed for a first heart transplant in Germany in 1997. Main outcome measure: Mortality, stratified by heart failure severity. Results: Within 1 year after listing, patients with a predicted high risk had the highest global death rate (51% v 32% and 29% for medium and low risk patients respectively; P<0.0001), had the highest risk of dying on the waiting list (32% v 20% and 20%; P=0.0003), and were more likely to receive a transplant (48% v 45% and 41%; P=0.01). Differences between the risk groups in outcome after transplantation did not reach significance (P=0.2). Transplantation was not associated with a reduction in mortality risk for the total cohort, but it did provide a survival benefit for the high risk group. Conclusion: Cardiac transplantation in Germany is currently associated with a survival benefit only in patients with a predicted high risk of dying on the waiting list. Patients with a predicted low or medium risk have no reduction in mortality risk associated with transplantation; they should be managed with organ saving approaches rather than transplantation.

Myocyte loss in chronic heart failure.

This study examined whether or not there is progressive loss of individual myocytes in established heart failure, accounting for the progressive left ventricular dysfunction; whether such loss is by necrosis or apoptosis; and whether such loss is more pronounced in ischaemic heart disease or idiopathic dilated cardiomyopathy. Tissue for patients undergoing cardiac transplantation for clinical end‐stage heart disease was used. The clinical diagnosis was not known to the observer at the time of analysis. Indices of potential myocyte loss were: detection of apoptotic nuclei in situ, using the TUNEL method, immunohistochemistry for CD120a, CD120b, CD95, perforin and granzyme B; binding of C9 complex; and lipofuscin deposition within macrophages. Interstitial macrophages and T cells and their relationship to myocyte loss were also examined. There is indeed low grade myocyte loss in chronic heart failure, but there was no difference between the disease groups; rather, there was marked patient‐to‐patient variation within each category. Thus in chronic heart failure myocyte loss does occur, and both necrosis and apoptosis contribute to this loss, irrespective of the underlying nature of the disease. Any mechanism which accounts for myocyte loss must be common to both conditions, rather than specific for a pre‐operative diagnosis. Copyright

Comparison of two strategies for myocardial management during coronary artery operations

Despite the current trend for using blood cardioplegia, ventricular fibrillation with intermittent ischemia is still used as a strategy to manage the myocardium with impressive results. These two methods of myocardial management were compared in 40 patients undergoing elective coronary artery operations using creatine kinase MB isoforms and troponin T assays. Each patient was randomized to have either cold blood cardioplegia (n = 20) or ventricular fibrillation with intermittent ischemia (n = 20) for myocardial management during the construction of distal anastomoses. Until recently, the comparison of different methods of myocardial management has been hindered by the lack of a specific and sensitive marker of myocardial damage. Analysis of creatine kinase MB isoforms (MB2, cardiac tissue form; MB1, plasma-modified form) and cardiac-specific troponin T (a structural protein) has been shown to improve the sensitivity for the detection of myocardial damage. There were no significant differences between the two groups in age, sex ratio, extent of disease, or left ventricular function. Blood samples for analysis were collected before cross-clamp application and at time intervals up to 48 hours after. Median peak creatine kinase MB2 activity was found to be significantly higher in the blood cardioplegia group compared with ventricular fibrillation (26.5 U/L versus 19.5 U/L, respectively, p = 0.04). Although median peak troponin T concentration was higher in the blood cardioplegia group, the difference failed to reach significance (2.2 ng/mL versus 1.6 ng/mL, p = 0.15).(ABSTRACT TRUNCATED AT 250 WORDS)

A prospective controlled trial of st. jude versus starr edwards aortic and mitral valve prostheses

BACKGROUND There is a paucity of controlled trials comparing the merits of different heart valve prostheses. In this prospective randomized trial we compared Starr Edwards and St. Jude prostheses in the aortic and mitral positions. METHODS Two hundred sixty-seven patients and 122 patients undergoing aortic and mitral valve replacement, respectively, were allocated by minimization to receive either St. Jude or Starr Edwards prostheses. Patients (2 patients were lost to follow-up) were followed up in a special clinic. Event definition, recording, and reporting were in accordance with published guidelines. RESULTS There were no demographic differences between patients receiving the two different valve models. With the exception of infective endocarditis, we found no differences in the rates of death or complication between patients receiving a Starr Edwards prosthesis or a St. Jude prosthesis in either position. Neither were there any differences between the two valve models in either position, in terms of symptomatic relief 5 years after surgery. CONCLUSIONS We found no differences in rates of complication or of symptomatic improvement between the Starr Edwards and St. Jude valve prostheses in either aortic or mitral position. Left ventricular function had such a marked effect on long-term survival that it overwhelmed any differences that might exist between different prosthetic designs. This confirms that historical comparisons are of limited value in deciding the respective merits of heart valve prostheses. The most reliable method of assessing surgical procedures is through prospective controlled trials.

Successful resection of obstructing airway granulation tissue following lung transplantation using endobronchial laser (Nd-YAG) therapy

OBJECTIVE Airway obstruction due to an excessive growth of granulation tissue at the level of the anastomosis is an important complication following lung transplantation which requires early diagnosis and treatment. We report encouraging experience in the management of this condition using endobronchial Nd:YAG laser therapy. METHODS Four adult lung transplant recipients developed airway anastomotic obstruction secondary to granulation tissue formation at 9, 10, 32 and 32 days following bilateral sequential lung transplantation (2 patients), en bloc double lung transplantation (1 patient) and single lung transplantation (1 patient). The diameter of the airways at the level of the anastomoses was reduced by 75, 30, 60, 60, 50 and 90%, respectively. Endobronchial Nd:YAG laser was applied via a fiberoptic bronchoscope introduced through a rigid bronchoscope. The granulation tissue was visualised and resected with photocoagulation with the laser using between 1000-2000 J depending on the amount of tissue present. Necrotic tissue was removed with large forceps. If the obstruction extended to the orifice of a lobar bronchus resection was undertaken in a staged fashion. RESULTS Airway patency was fully restored at two anastomotic sites, and restored to 90% patency at two and 80 and 75% at one each, respectively. This was associated with a significant improvement in pulmonary function in 3 patients. One patient had a subsequent bougie dilatation of a stenotic area and 2 patients received an endobronchial stent for tracheo or broncho-malacia. One patient died from a gastrointestinal haemorrhage. Three patients are well at 10, 17 and 18 months following transplantation and have no further granulation tissue recurrence. There were no complications directly attributable to laser therapy. CONCLUSION Our encouraging early experience leads us to suggest that Endobronchial Nd-YAG laser therapy should be considered in the management of airway anastomotic obstruction due to excessive granulation tissue formation after lung transplantation.

Regional Variations in Endothelin-1 and its Receptor Subtypes in Human Coronary Vasculature: Pathophysiological Implications in Coronary Disease

Endothelin-1 is a potent vasoconstrictor peptide and mitogen for vascular smooth muscle cells. Increased plasma or tissue levels of endothelin-1 have been described after myocardial infarction and in atherosclerosis, suggesting that this peptide may play a pathophysiological role in various coronary syndromes. Here, we have studied regional variations in ET-1 and its receptors in control and atherosclerotic human coronary vasculature using standard immunohistochemistry and in vitro autoradiography. ET-1 immunoreactivity was associated with luminal endothelial cells and smooth muscle cells at regions of atherosclerosis. ET(A) receptors were present on smooth muscle cells of coronary arteries and on cardiac myocytes. Medial ET(B) receptor binding at the proximal region of coronary arteries was weak, but increased significantly towards distal regions of this vessel (p<0.005 in control and p<0.0005 in ischaemic heart disease). Microvascular endothelial cells in the adventitia of coronary arteries, myocardial microvessels and the endocardial endothelium expressed the ET(B) receptor exclusively. The receptor variations revealed in this study provide supporting evidence that ET-1 is associated with (1) vascular smooth muscle and endothelial cell proliferation, including areas of intimal hyperplasia and regions of neovascularization (2) increased ET-1-induced reactivity of distal portions of the human coronary artery, (3) ET-1-mediated constriction of myocardial microvessels. These results provide new insights into different potential roles for this peptide in healthy and diseased human coronary vasculature.

Effect of receiving a heart transplant: analysis of a national cohort entered on to a waiting list, stratified by heart failure severityCommentary: Time for a controlled trial?

Abstract Objective: To determine whether there is a survival benefit associated with cardiac transplantation in Germany. Design: Prospective observational cohort study. Setting: All 889 adult patients listed for a first heart transplant in Germany in 1997. Main outcome measure: Mortality, stratified by heart failure severity. Results: Within 1 year after listing, patients with a predicted high risk had the highest global death rate (51% v 32% and 29% for medium and low risk patients respectively; P<0.0001), had the highest risk of dying on the waiting list (32% v 20% and 20%; P=0.0003), and were more likely to receive a transplant (48% v 45% and 41%; P=0.01). Differences between the risk groups in outcome after transplantation did not reach significance (P=0.2). Transplantation was not associated with a reduction in mortality risk for the total cohort, but it did provide a survival benefit for the high risk group. Conclusion: Cardiac transplantation in Germany is currently associated with a survival benefit only in patients with a predicted high risk of dying on the waiting list. Patients with a predicted low or medium risk have no reduction in mortality risk associated with transplantation; they should be managed with organ saving approaches rather than transplantation.

Intermediate term results of total lymphoid irradiation for the treatment of non-specific graft dysfunction after heart transplantation.

BACKGROUND A proportion of heart transplant recipients develop poor graft function in the absence of cellular infiltrate in endomyocardial biopsies or transplant associated coronary artery disease. The condition has a poor prognosis and its aetiology is poorly understood. We report encouraging intermediate term results with total lymphoid irradiation (TLI) in the management of this condition. METHODS Eleven adult cardiac transplant recipients who developed severe allograft dysfunction (NYHA class-4) at a median period of 4 months after orthotopic heart transplantation were successfully treated with TLI. Endomyocardial biopsies and coronary angiography were normal in each patient and biventricular failure developed in spite of immunosuppression with Cyclosporin-A, Azathioprine, oral Prednisolone, Cyclophosphamide and intravenous Methylprednisolone therapy. Total lymphoid irradiation was given with standard Mantle and inverted Y-fields over ten treatments to achieve a cumulative dose of 8 Gy. RESULTS Each patient had a significant improvement in clinical response and in ventricular performance within 2 months of commencing TLI. Nine patients are currently well (four NHYA class-1, five NHYA class-2) at 4-48 (median 26) months following TLI. Two patients died; one from bacterial septicaemia and one as a consequence of chronic renal failure. Three patients developed opportunistic infection which was successfully treated with appropriate antimicrobial agents. An Ebstein-Barr virus associated lymphoproliferative disorder occurred in one patient and was successfully treated by reduction in immunosuppression and high dose Acyclovir. Two patients developed transient bone marrow suppression. CONCLUSION The intermediate term results of TLI in the management of poor graft function in cardiac transplant recipients with normal endomyocardial biopsies and coronary angiography are encouraging. Although complications of opportunistic infection, bone marrow suppression and lymphoproliferative disorder occurred, treatment was successful in each case.