Personalized external aortic root support: a review of the current status.

Personalized external aortic root support (PEARS) is an emerging technology. It is a pre-emptive operation to halt aortic root expansion and maintain aortic valve function in Marfan syndrome and is also applicable to aortic root aneurysms of other aetiologies. To fully evaluate PEARS, awareness of all those who advise these patients is necessary to ensure that patients are fully informed of the alternative operations, to carefully build experience, to ensure safety and quality and to monitor outcomes. Herein, we present a summary of published methods and outcomes and the arrangements in place for fuller evaluation.

Long term survival with thoracoscopic versus open lobectomy: propensity matched comparative analysis using SEER-Medicare database.

OBJECTIVE: To compare long term survival after minimally invasive lobectomy and thoracotomy lobectomy. DESIGN: Propensity matched analysis. SETTING: Surveillance, Epidemiology and End Results (SEER)-Medicare database. PARTICIPANTS: All patients with lung cancer from 2007 to 2009 undergoing lobectomy. MAIN OUTCOME MEASURE: Influence of less invasive thoracoscopic surgery on overall survival, disease-free survival, and cancer specific survival. RESULTS: From 2007 to 2009, 6008 patients undergoing lobectomy were identified (n=4715 (78%) thoracotomy). The median age of the entire cohort was 74 (interquartile range 70-78) years. The median length of follow-up for entire group was 40 months. In a matched analysis of 1195 patients in each treatment category, no statistical differences in three year overall survival, disease-free survival, or cancer specific survival were found between the groups (overall survival: 70.6% v 68.1%, P=0.55; disease-free survival: 86.2% v 85.4%, P=0.46; cancer specific survival: 92% v 89.5%, P=0.05). CONCLUSION: This propensity matched analysis showed that patients undergoing thoracoscopic lobectomy had similar overall, cancer specific, and disease-free survival compared with patients undergoing thoracotomy lobectomy. Thoracoscopic techniques do not seem to compromise these measures of outcome after lobectomy.

A method for early evaluation of a recently introduced technology by deriving a comparative group from existing clinical data: a case study in external support of the Marfan aortic root.

OBJECTIVE: During the early phase of evaluation of a new intervention, data exist for present practice. The authors propose a method of constructing a fair comparator group using these data. In this case study, the authors use the example of external aortic root support, a novel alternative to aortic root replacement. DESIGN: A matched comparison group, of similar age, aortic size and aortic valve function to those having the novel intervention, was constructed, by minimization, from among patients having conventional aortic root replacement in other hospitals during the same time frame. SETTING: Three cardiac surgical units in England. PATIENTS: The first 20 patients, aged 16-58 years with aortic root diameters of 40-54 mm, having external support surgery were compared with 20 patients, aged 18-63 years and aortic root diameters of 38-58 mm, who had conventional aortic root replacement, between May 2004 and December 2009. INTERVENTIONS: A pliant external mesh sleeve, customised by computer-aided design, encloses the whole of the ascending aorta. The comparator group had conventional aortic root replacement, 16 valve-sparing and four with composite valved grafts. MAIN OUTCOME MEASURES: Duration of cardiopulmonary bypass (CPB), myocardial ischaemic time, blood loss and transfusion of blood, platelets and clotting factors. RESULTS: Comparing total root replacement and customised aortic root support surgery: CPB (median (range)) was 134 (52-316) versus 0 (0-20) min; myocardial ischaemia 114 (41-250) versus 0 (0-0) min; 4 h blood loss was 218 (85-735) versus 50 (25-400) ml; and 9/18 had blood transfusion, 9/18 platelets and 12/18 fresh frozen plasma after root replacement versus 1/20, 0/20 and 0/20, respectively, for the novel surgery. CONCLUSIONS: Avoidance or large reductions in CPB, myocardial ischaemia and blood product usage were achieved with the novel surgery. These data are of use in decision analysis and health economic evaluation and are available early in evaluation before randomised trial data are available.

Evaluation and stages of surgical innovations.

Surgical innovation is an important part of surgical practice. Its assessment is complex because of idiosyncrasies related to surgical practice, but necessary so that introduction and adoption of surgical innovations can derive from evidence-based principles rather than trial and error. A regulatory framework is also desirable to protect patients against the potential harms of any novel procedure. In this first of three Series papers on surgical innovation and evaluation, we propose a five-stage paradigm to describe the development of innovative surgical procedures.

No surgical innovation without evaluation: the IDEAL recommendations.

Surgery and other invasive therapies are complex interventions, the assessment of which is challenged by factors that depend on operator, team, and setting, such as learning curves, quality variations, and perception of equipoise. We propose recommendations for the assessment of surgery based on a five-stage description of the surgical development process. We also encourage the widespread use of prospective databases and registries. Reports of new techniques should be registered as a professional duty, anonymously if necessary when outcomes are adverse. Case series studies should be replaced by prospective development studies for early technical modifications and by prospective research databases for later pre-trial evaluation. Protocols for these studies should be registered publicly. Statistical process control techniques can be useful in both early and late assessment. Randomised trials should be used whenever possible to investigate efficacy, but adequate pre-trial data are essential to allow power calculations, clarify the definition and indications of the intervention, and develop quality measures. Difficulties in doing randomised clinical trials should be addressed by measures to evaluate learning curves and alleviate equipoise problems. Alternative prospective designs, such as interrupted time series studies, should be used when randomised trials are not feasible. Established procedures should be monitored with prospective databases to analyse outcome variations and to identify late and rare events. Achievement of improved design, conduct, and reporting of surgical research will need concerted action by editors, funders of health care and research, regulatory bodies, and professional societies.

Challenges in evaluating surgical innovation.

Research on surgical interventions is associated with several methodological and practical challenges of which few, if any, apply only to surgery. However, surgical evaluation is especially demanding because many of these challenges coincide. In this report, the second of three on surgical innovation and evaluation, we discuss obstacles related to the study design of randomised controlled trials and non-randomised studies assessing surgical interventions. We also describe the issues related to the nature of surgical procedures-for example, their complexity, surgeon-related factors, and the range of outcomes. Although difficult, surgical evaluation is achievable and necessary. Solutions tailored to surgical research and a framework for generating evidence on which to base surgical practice are essential.

Are randomised trials needed in the era of rapidly evolving technologies?

New technologies are expensive. The health care budget cannot expand indefinitely so if new treatments are introduced they may have to displace other treatments, or prevent other new treatments coming into practice. This is not simply a money saving exercise; it is accepted that new high technology treatments may cost more to implement but they must be worth the money spent in comparison with other treatments. Therefore cardiothoracic surgeons must first demonstrate that our treatments are effective. Then we need evidence of cost effectiveness in comparison with other therapies.

MADCAP: a graphical method for assessing risk scoring systems.

OBJECTIVE: We set out to develop a method for assessing the performance of clinical risk models over the spectrum of risks and to assess the performance of the EuroSCORE risk model used in cardiac surgery. METHODS: We developed a graphical method for assessing the performance of clinical risk models over the spectrum of risks. To illustrate the technique, we analysed retrospective data concerning 9268 patients that underwent cardiac surgery and for whom both the additive EuroSCORE prediction of risk of morality and vital status at 30 days were available. RESULTS: The graphical tool developed, called MADCAP (Mean Adjusted Deaths Compared Against Predictions), can be used to highlight systematic features of the performance of a clinical risk model. Its use in the current study indicates that the additive version of the EuroSCORE model seems to underestimate risk amongst low-risk cases (0% and 1%). Otherwise the score systematically favours risk avoiding behaviour as the risk model underestimates mortality for 2--6% prediction but not at 7% and above. CONCLUSION: The robustness of case-mix adjusted audit is dependent on the performance of the risk scoring system over the entire spectrum of risk. If we are to use risk adjustment of mortality rates when comparing outcomes obtained by different units or individual surgeons, it is essential that we continually review the performance of the risk adjustment method. The MADCAP method presented here provides a useful tool to this end.

Pharmacologic prophylaxis for postoperative atrial tachyarrhythmia in general thoracic surgery: evidence from randomized clinical trials.

BACKGROUND: Atrial tachyarrhythmia is the most common complication after general thoracic surgery and is associated with significant morbidity, longer hospital stay, and higher costs. We sought to determine whether the use of antiarrhythmic medications is associated with a reduced rate of postoperative atrial tachyarrhythmia. METHODS: MEDLINE, EMBASE, Cochrane Database of clinical trials (1980-2003), and reference lists of relevant articles were searched for randomized controlled trials with placebo control, general thoracic patients, and noncombined and prophylactic use of the medications. Search, data abstraction, and analyses were performed and confirmed by at least 2 authors. A fixed-effects model was used to perform meta-analyses. RESULTS: There were 11 unique trials (total n = 1294) that met the inclusion criteria. Calcium-channel blockers and beta-blockers reduced the risk of atrial tachyarrhythmia in 4 and 2 trials, respectively (relative risk of 0.50 and 95% confidence interval of 0.34-0.73; relative risk of 0.40 and 95% confidence interval of 0.17-0.95, respectively). However, beta-blockers tended to increase the risk of pulmonary edema (relative risk, 2.15; 95% confidence interval, 0.74-6.23). Magnesium tested in one unblinded trial also reduced the risk of atrial tachyarrhythmia (relative risk, 0.4; 95% confidence interval, 0.21-0.78). On the other hand, digitalis preparations were found to be harmful because they increased the risk of atrial tachyarrhythmia in 3 trials (relative risk, 1.51; 95% confidence interval, 1.00-2.28). Finally, 2 other medications, flecainide and amiodarone, were each tested in a single small trial, and their effects were associated with great uncertainty. CONCLUSIONS: Calcium-channel blockers and beta-blockers are effective in reducing postoperative atrial tachyarrhythmia. The use of these medications should be individualized, and possible adverse events of beta-blockers should be taken into account. Randomized clinical trials do not support the use of digitalis in general thoracic surgery. The value of magnesium as a supplement to a main prophylactic regimen should be explored.

Assessment of whether in-hospital mortality for lobectomy is a useful standard for the quality of lung cancer surgery: retrospective study.

OBJECTIVES: To calculate in-hospital mortality after lobectomy for primary lung cancer in the United Kingdom; to explore the validity of using such data to assess the quality of UK thoracic surgeons; and to investigate the relation between in-hospital mortality and the number of procedures performed by surgeons. DESIGN: Retrospective study. SETTING: 36 departments dealing with thoracic surgery in UK hospitals. PARTICIPANTS: 4028 patients who had undergone lobectomy for primary lung cancer by one of 102 surgeons. MAIN OUTCOME MEASURES: In-hospital mortality in relation to individual surgeons, among all patients, and among each of five groups of patients defined by the number of operations performed by the surgeon. RESULTS: 103 patients (2.6%, 95% confidence interval 2.1% to 3.1%) died after surgery during the same hospital admission. No significant difference was found for in-hospital mortality between the five groups. CONCLUSIONS: The number of procedures performed by a thoracic surgeon is not related to in-hospital mortality. Reporting data on in-hospital mortality after lobectomy for primary lung cancer is a poor tool for measuring a surgeon's performance.