Matthew Shaw

Atrial fibrillation postcardiac surgery: a common but a morbid complication

OBJECTIVES Despite all the advances in cardiac surgery, atrial fibrillation (AF) remains a common postoperative complication with unclear predisposing factors. Postoperative AF is often a short-lived and a self-limiting condition, but can result in debilitating and even lethal consequences. The aim of this study is to assess the effect of AF on patients postcardiac surgery. METHODS In this retrospective study, we prospectively reviewed patient data for our institution for a 10-year period; a total of 17,379 patients with preoperative sinus rhythm (SR) who underwent cardiac surgery were included, of which 4984 (28.7%) had developed postoperative AF for any length of time. After propensity matching for the preoperative characteristics between the two groups; the group with AF and the group who remained in SR, postoperative complications, in-hospital mortality, mid-term survival rate (five years), and long-term survival rate (10 years) were compared. RESULTS Before and after adjusting for the preoperative characteristics and type of the operation, postoperative complications, such as renal failure, surgical wound infection, stroke and myocardial infarction were significantly higher in the AF group compared to the SR group (P < 0.001). Inotropic support, use of intra-aortic balloon pump, and ventilation time were also considerably higher in the AF patients (P < 0.001). In-hospital mortality was also higher in the AF group. Likewise, 30-day, mid-term and long-term mortality rates were found to be considerably higher in the AF group. CONCLUSIONS Despite all the modern anti-arrhythmic drugs, the incidence of AF remains unchanged. Patients who develop AF postcardiac surgery show a significantly worse outcome compared to those without AF. This study also highlights the importance of anticoagulation in AF to prevent the devastating consequences as a result of a cerebral stroke. We believe that not only immediate treatment of AF postoperatively should be implemented, but also measures should be taken to identify the risk factors of AF and to prevent AF postcardiac surgery.

Acute type A aortic dissection in the United Kingdom: Surgeon volume-outcome relation

Objectives Surgery for acute type A aortic dissection (ATAD) carries a high risk of operative mortality. We examined the surgeon volume‐outcome relation with respect to in‐hospital mortality for patients presenting with this pathology in the United Kingdom. Method Between April 2007 and March 2013, 1550 ATAD procedures were identified from the National Institute for Cardiovascular Outcomes Research database. A total of 249 responsible consultant cardiac surgeons from the United Kingdom recorded 1 or more of these procedures in their surgical activity over this period. We describe the patient population and mortality rates, focusing on the relationship between surgeon volume and in‐hospital mortality. Results The mean annual volume of procedures per surgeon during the 6‐year period ranged from 1 to 6.6. The overall in‐hospital mortality rate was 18.3% (283/1550). A mortality improvement at the 95% level was observed with a risk‐adjusted mean annual volume >4.5. Surgeons with a mean annual volume <4 over the study period had significantly higher in‐hospital mortality rates in comparison with surgeons with a mean annual volume ≥4 (19.3% vs 12.6%; P = .015). Conclusions Patients with ATAD who are operated on by lower‐volume surgeons experience higher levels of in‐hospital mortality. Directing these patients to higher‐volume surgeons may be a strategy to reduce in‐hospital mortality.

Framingham risk-based survival of non-small-cell lung cancer

This study was undertaken to determine whether the Framingham cardiovascular risk prediction model can identify patients who will have reduced 5-year survival after resection for primary lung cancer. The Framingham risk model for predicting cardiovascular death rates in a 5-year period was calculated for 1,981 patients undergoing resection for non-small-cell lung cancer. Receiver operator curve analysis was performed to determine a cutoff with regard to Framingham risk, and this was utilized to construct Kaplan-Meier survival curves for stages I, II, and III. Cox regression analysis was used to determine factors significantly affecting long-term survival. The Framingham risk model predicted that 0.015% to 26.7 % (mean, 5.2%) of our patients would die over a 5-year period. Univariate analysis revealed the Framingham score as being significant for stages I and II, but not III. Cox regression analysis demonstrated age, body mass index, pneumonectomy, stage I, stage III, stage IV, and Framingham score were all significant determinants of 5-year survival. Framingham-based cardiovascular risk prediction in patients undergoing resection for non-small-cell lung cancer stages I and II defined a group with significantly worse 5-year survival.

Comparing the outcome of on-pump versus off-pump coronary artery bypass grafting in patients with preoperative atrial fibrillation

OBJECTIVES Around 5-15% of patients undergoing coronary artery bypass grafting (CABG) suffer from preoperative/pre-existing atrial fibrillation (PAF). This is a benign arrhythmia but can affect the outcome of the surgery. The aim of this study was to assess the effect of PAF on the immediate postoperative course of patients undergoing on-pump (ONCAB) vs. off-pump (OPCAB) CABG. METHODS Over a 10-year period, data were prospectively entered into the database of our institution. A total of 10,461 patients underwent CABG, of whom 477 (4.6%) were in PAF. We analyzed these patients in two separate groups: group A (n=310) who underwent ONCAB and group B (n=167) who underwent OPCAB. After 4:1 propensity matching and adjusting for the preoperative and operative characteristics of these two groups with patients in SR (sinus rhythm), early, mid- and long-term outcomes of PAF patients were analyzed. RESULTS After adjusting for preoperative characteristics, postoperative complications were significantly higher in patients who had ONCAB when there was PAF compared to those in SR (P<0.001). In the OPCAB patients, on the other hand, there was no statistically significant difference in the postoperative complications between the patients with preoperative SR or PAF. In-hospital and short-term mortality were no different in the PAF group undergoing OPCAB compared to those in SR; however, the mid- and long-term survival rates in PAF patients who underwent OPCAB/ONCAB were worse compared than was seen in SR. CONCLUSIONS PAF is associated with a higher incidence of postoperative complications. Our results have demonstrated that patients in PAF undergoing ONCAB are more susceptible to the postoperative complications compared to those in SR. However, there were no differences in mid- and long-term outcomes.

Aortic Valve Repair: A Systematic Review and Meta-analysis of Published Literature.

UNLABELLED Background : It is widely accepted that aortic valve disease is surgically managed with aortic valve replacement (AVR) using different available prostheses. The long-term survival, durability of the valve, and freedom from reoperation after AVR are well established in published literature. Over the past two decades, aortic valve repair (AVr) has evolved into an accepted surgical option for patients with aortic valve disease. We review and analyze the published literature on AVr. Methods : A systematic review of the current literature was performed through three electronic databases from inception to August 2013 to identify all relevant studies relating to aortic valve repair. Articles selected were chosen by two reviewers. Articles were excluded if they contained a pediatric population or if the patient number was less than 50. RESULTS Twenty-four studies conformed to the inclusion criteria for inclusion in the systematic review. In total, 4986 patients underwent aortic valve repair. 7 studies represented bicuspid aortic valve (BAV) repair, 5 studies represented cusp prolapse, and 3 studies represented valve repair with root dilation or aneurysm. Overall weighted in-hospital mortality for all studies was low (1.46% ± 1.21). Preoperative aortic insufficiency (AI) ≥ 2+ did not correlate to reoperation for valve failure (Pearsons Rs 0.2705, P = 0.2585). AI at discharge was reported in 9 studies with a mean AI ≥ 2+ in 6.1% of patients. Weighted average percentage for valve reoperation following BAV repair was 10.23% ± 3.2. Weighted average reoperation following cusp prolapse repair was 3.83 ± 1.96. Weighted average reoperation in aortic valve sparing procedures with root replacement was 4.25% ± 2.46. Although there are limitations and complications of prosthetic valves, especially for younger individuals, there is ample published literature that confers strong evidence for AVR. On the contrary, aortic valve repair may be a useful option for selected patients, but there is lack of uniformity in data and absence of compelling supporting evidence. An international multi-center study comparing and assessing the results between AVR & AVr is the next step required. Currently, higher levels of evidence do not exist for aortic valve repair.

Unwarranted Variation in the Quality of Care for Patients With Diseases of the Thoracic Aorta

Background Thoracic aortic disease has a high mortality. We sought to establish the contribution of unwarranted variation in care to regional differences in outcomes observed in patients with thoracic aortic disease in England. Methods and Results Data from the Hospital Episode Statistics (HES) and the National Adult Cardiac Surgery Audit (NACSA) were extracted. A parallel systematic review/meta‐analysis through December 2015, and structure and process questionnaire of English cardiac surgery units were also accomplished. Treatment and mortality rates were investigated. A total of 24 548 adult patients in the HES study, 8058 in the NACSA study, and 103 543 from a total of 33 studies in the systematic review were obtained. Treatment rates for thoracic aortic disease within 6 months of index admission ranged from 7.6% to 31.5% between English counties. Risk‐adjusted 6‐month mortality in untreated patients ranged from 19.4% to 36.3%. Regional variation persisted after adjustment for disease or patient factors. Regional cardiac units with higher case volumes treated more‐complex patients and had significantly lower risk‐adjusted mortality relative to low‐volume units. The results of the systematic review indicated that the delivery of care by multidisciplinary teams in high‐volume units resulted in better outcomes. The observational analyses and the online survey indicated that this is not how services are configured in most units in England. Conclusions Changes in the organization of services that address unwarranted variation in the provision of care for patients with thoracic aortic disease in England may result in more‐equitable access to treatment and improved outcomes.

A Perspective on Natural History and Survival in Nonoperated Thoracic Aortic Aneurysm Patients.

There are many questions that remain unanswered in the understanding of the natural history of thoracic aortic aneurysm (TAA). This review will critically appraise the current published evidence on the natural history of TAA in nonoperated patients and their present rates of survival.

The Impact of Diabetes Mellitus on Two-Year Mortality Following Contemporary Percutaneous Coronary Intervention: Implications for Revascularization Practice

OBJECTIVE To assess the impact of diabetes on 2-year mortality in current PCI practice. BACKGROUND In patients with coronary artery disease undergoing revascularization, diabetes mellitus is associated with higher mortality. METHODS A retrospective analysis was done of all patients undergoing PCI at our tertiary center between January 2000 and December 2004. There were 6,160 PCI procedures performed in 5,759 patients who received at least one stent. Of these patients, 801 (13.9%) were diabetic and 4,958 (86.1%) were nondiabetic. The primary outcome measure of the study was all-cause mortality. All patients were followed up for a period of 2 years. Multivariate logistic regression analysis was used to test for a potential independent association between diabetic status and follow-up mortality. RESULTS Before adjustment, a trend toward higher mortality was observed in diabetic patients compared to non-diabetics at 1 year (3.2% vs 2.4%) and 2 years (5.1% vs 3.8%), P = 0.12. Independent predictors for mortality were increasing age, renal dysfunction, peripheral vascular disease, NYHA class >2, urgent PCI, treating left main stem lesions, vessel diameter < or = 2.5 mm, and 3-vessel disease. The use of drug-eluting stent was associated with a reduction in mortality. Diabetes was found to have no independent impact on mortality following PCI (odds ratio = 1.08; 95% confidence intervals = 0.73-1.60; P = 0.71). CONCLUSION The presence of diabetes was not an independent predictor of mortality following PCI. A diabetic patient that does not require insulin treatment and has no evidence of macro- or microvascular diabetic disease could enjoy a PCI outcome similar to nondiabetic subjects.

Secondary Open Aortic Procedure Following Thoracic Endovascular Aortic Repair: Meta‐Analytic State of the Art

Background Thoracic endovascular aortic repair is characterized by a substantial need for reintervention. Secondary open aortic procedure becomes necessary when further endoluminal options are exhausted. This synopsis and quantitative analysis of available evidence aims to overcome the limitations of institutional cohort reports on secondary open aortic procedure. Methods and Results Electronic databases were searched from 1994 to the present date with a prospectively registered protocol. Pooled quantification of pre/intraoperative variables, and proportional meta‐analysis with random effect model of early and midterm outcomes were performed. Subgroup analysis was conducted for patients who had early mortality. Fifteen studies were elected for final analysis, encompassing 330 patients. The following values are expressed as “pooled mean, 95% confidence interval.” Type B dissection was the most common pathology at index thoracic endovascular aortic repair (51.2%, 44.4–57.9). The most frequent indication for secondary open aortic procedure was endoleak (39.7%, 34.6–45.1). More than half of patients had surgery on the descending aorta (51.2%, 45.8–56.6), and one fourth on the arch (25.2%, 20.8–30.1). Operative mortality was 10.6% (7.4–14.9). Neurological morbidity was substantial between stroke (5.1%, 2.8–9.1) and paraplegia (8.3%, 5.2–13.1). At 2‐year follow‐up, mortality (20.4%, 11.5–33.5) and aortic adverse event (aortic death 7.7%, 4.3–13.3, tertiary aortic open procedure 7.4%, 4.0–13.2) were not negligible. Conclusions In the secondary open aortic procedure population, type B dissection was both the most common pathology and the one associated with the lowest early mortality, whereas aortic infection and extra‐anatomical bypass were associated with the most ominous prognosis.

Liverpool Aortic Surgery Symposium V: New Frontiers in Aortic Disease and Surgery

Aortic aneurysm disease is a complex condition that requires a multidisciplinary approach in management. The innovation and collaboration among vascular surgery, cardiothoracic surgery, interventional radiology, and other related specialties is essential for progress in the management of aortic aneurysms. The Fifth Liverpool Aortic Surgery Symposium that was held in May 2013 aimed at bringing national and international experts from across the United Kingdom and the globe to deliver their thoughts, applications, and advances in aortic and vascular surgery. In this report, we present a selected short synopsis of the key topics presented at this symposium.