A.J. Murday

N-terminal brain natriuretic peptide is predictive of death after cardiac transplantation

Cardiac transplantation is an important treatment option for those patients with end stage heart failure who have failed to respond to disease modifying treatment. However, cardiac transplantation is not without risk, with the one year mortality around 19%,1 and identifying patients at the highest risk of death is notoriously difficult. Brain natriuretic peptide (BNP) and the N-terminal portion of pro-brain natriuretic peptide (NT-proBNP) are now well established diagnostic and adverse prognostic markers in all stages of congestive heart failure. Indeed, we have shown that NT-proBNP is predictive of death before cardiac transplantation.2 Studies have also shown that increasing BNP concentrations precede cardiac allograft rejection and are associated with poor survival late after transplantation.3 However, the prognostic ability of NT-proBNP immediately after cardiac transplantation has not been evaluated. The goal of this study was therefore to assess the short term prognostic ability of NT-proBNP in patients after cardiac transplantation. We prospectively studied 26 consecutive patients undergoing orthotopic cardiac transplantation in the Scottish Cardiopulmonary Transplant Unit between September 2001 and September 2003. The primary end point was all cause mortality. The median follow up was 477 days (range 20–922 days). No patients were lost to follow up. Blood for NT-proBNP was collected in EDTA containing tubes before each routine right ventricular endomyocardial biopsy. The samples were then spun at 3000 rpm for 10 minutes at 0°C. Plasma was extracted and frozen in aliquots at −70°C until analysis. NT-proBNP …

Informed consent in cardiac surgery: is it truly informed?

Objective To develop a validated questionnaire to measure how informed patients are when giving consent for elective coronary artery bypass grafting. Methods We developed a questionnaire covering the domains described in the consent guidelines published by the General Medical Council. The questionnaire was developed for use in face-to-face interviews as opposed to a self-administered questionnaire. Interviews were conducted after the patients had given consent for surgery. A total of 41 patients were interviewed. To validate the questionnaire we tested the interobserver reliability by using four different interviewers and the construct validity by comparing it with area deprivation index and with predicted intelligence quotient scores obtained from the National Adult Reading Test. Results The correlation of the ranking of the questions between the interviewers was satisfactory (Spearmans rank correlation coefficient, rs = 0.84–0.89). The total questionnaire scores correlated well with predicted intelligence quotient scores (rs = 0.48) but not with area deprivation index (rs = 0.01). Questions with the worst scores were those related to mortality, morbidity, alternative treatment options and their relative success rates and risks. Conclusions We have developed a validated questionnaire which tests patients level of knowledge with respect to surgical myocardial revascularisation. Our study identified areas of informed consent where the minimal level of knowledge is below the recommended level. The questionnaire could be used in audits and clinical trials in patients undergoing coronary artery bypass grafting. It could be used as a tool to measure the effectiveness of patient education programmes. With appropriate changes, this instrument could also be applied in other fields of medical intervention, which require patients to give informed consent.

Decreased morbidity following long saphenous vein harvesting using a minimally invasive technique: a randomised controlled trial comparing two techniques for long saphenous vein harvest.

ObjectivesThe objective of this study was to compare the morbidity associated with long saphenous vein harvesting using the traditional open technique (A) against a minimally invasive technique using the Mayo vein stripper (B) that involves multiple short incisions.DesignWe conducted a prospective randomized controlled study in 80 patients undergoing first time coronary artery bypass grafting. Pain and healing was assessed on each postoperative day. Rings of long saphenous vein were subjected to organ-bath evaluation of endothelium-dependent and endothelium-independent relaxation.ResultsThree patients were excluded from the study, leaving 38 patients in Group A and 39 in Group B. With respect to operative procedure, Group A had a greater length of vein harvested than Group B. There was no statistical difference in pain scores and endothelium-dependent or endothelium-independent relaxation between the two groups. However there were significantly more infections in Group A compared with Group B.ConclusionHarvesting vein through multiple incisions using the Mayo vein stripper is quicker, results in fewer infections and has no deleterious effect on endothelial function compared to open technique.

N-terminal pro-brain natriuretic peptide. a new gold standard in predicting mortality in patients with advanced heart failure

AIMS The selection of patients for cardiac transplantation (CTx) is notoriously difficult and traditionally involves clinical assessment and an assimilation of markers of the severity of CHF such as the left ventricular ejection fraction (LVEF), maximum oxygen uptake (peak VO2) and more recently, composite scoring systems e.g. the heart failure survival score (HFSS). Brain natriuretic peptide (BNP) is well established as an independent predictor of prognosis in mild to moderate chronic heart failure (CHF). However, the prognostic ability of NT-proBNP in advanced heart failure is unknown and no studies have compared NT-proBNP to standard clinical markers used in the selection of patients for transplantation. The purpose of this study was to examine the prognostic ability of NT-proBNP in advanced heart failure and compare it to that of the LVEF, peak VO2 and the HFSS. METHODS AND RESULTS We prospectively studied 142 consecutive patients with advanced CHF referred for consideration of CTx. Plasma for NT-proBNP analysis was sampled and patients followed up for a median of 374 days. The primary endpoint of all-cause mortality was reached in 20 (14.1%) patients and the combined secondary endpoint of all-cause mortality or urgent CTx was reached in 24 (16.9%) patients. An NT-proBNP concentration above the median was the only independent predictor of all cause mortality (chi2=6.03, P=0.01) and the combined endpoint of all cause mortality or urgent CTx (chi2 =12.68, P=0.0004). LVEF, VO2 and HFSS were not independently predictive of mortality or need for urgent cardiac transplantation in this study. CONCLUSION A single measurement of NT-proBNP in patients with advanced CHF, can help to identify patients at highest risk of death, and is a better prognostic marker than the LVEF, VO2 or HFSS.