Patient-Specific Haemodynamic Analysis of Virtual Grafting Strategies in Type-B Aortic Dissection: Impact of Compliance Mismatch

INTRODUCTION

Compliance mismatch between the aortic wall and Dacron Grafts is a clinical problem concerning aortic haemodynamics and morphological degeneration. The aortic stiffness introduced by grafts can lead to an increased left ventricular (LV) afterload. This study quantifies the impact of compliance mismatch by virtually testing different Type-B aortic dissection (TBAD) surgical grafting strategies in patient-specific, compliant computational fluid dynamics (CFD) simulations.

MATERIALS AND METHODS

A post-operative case of TBAD was segmented from computed tomography angiography data. Three virtual surgeries were generated using different grafts; two additional cases with compliant grafts were assessed. Compliant CFD simulations were performed using a patient-specific inlet flow rate and three-element Windkessel outlet boundary conditions informed by 2D-Flow MRI data. The wall compliance was calibrated using Cine-MRI images. Pressure, wall shear stress (WSS) indices and energy loss (EL) were computed.

RESULTS

Increased aortic stiffness and longer grafts increased aortic pressure and EL. Implementing a compliant graft matching the aortic compliance of the patient reduced the pulse pressure by 11% and EL by 4%. The endothelial cell activation potential (ECAP) differed the most within the aneurysm, where the maximum percentage difference between the reference case and the mid (MDA) and complete (CDA) descending aorta replacements increased by 16% and 20%, respectively.

CONCLUSION

This study suggests that by minimising graft length and matching its compliance to the native aorta whilst aligning with surgical requirements, the risk of LV hypertrophy may be reduced. This provides evidence that compliance-matching grafts may enhance patient outcomes.

Preoperative B-Type Natriuretic Peptides to Predict Postoperative Atrial Fibrillation in Cardiac Surgery: A Systematic Review and Meta-Analysis

BACKGROUND

Post-operative atrial fibrillation (AF) is the most common complication following cardiac surgery. There has been extensive exploration of clinical variables, imaging, and biomarkers to predict its occurrence after cardiac surgery. In this study, we examine the emerging biomarkers B-type natriuretic peptide (BNP) and N-terminal proBNP (NT-proBNP) to assess their pre-operative values and correlations with the occurrence of post-operative AF in patients undergoing cardiac surgery.

METHODS

A comprehensive literature search was conducted using PubMed, EMBASE, MEDLINE via Ovid, ClinicalTrials.Gov, Scopus, and Cochrane Central Register of Controlled Trials (CENTRAL) to identify studies published until March 2023. The studies were included if they reported pre-operative BNP or NT-proBNP values and the development of post-operative AF in cardiac surgery patients. Subsequently, data were extracted, and a meta-analysis was performed using Review Manager 5.4 4 (The Cochrane Collaboration, 2020) and SPSS version 28 (IBM Corp, Armonk, NY, USA) to assess the difference between pre-operative BNP and NT-proBNP levels between patients with post-operative AF (AF group) and those without (No-AF group) using a random-effect model. Further analysis was performed in three subgroups: isolated coronary artery bypass grafting, isolated valve, and combined/mixed surgery group.

RESULT

A total of 20 studies, including 9,079 participants were identified and included in the systematic review and meta-analysis. Pre-operative BNP levels were reported in 11 studies, and NT-proBNP levels were reported in 10 studies, of which one study reported both BNP and NT-proBNP levels. There is an overall significant difference between pre-operative levels of BNP (p=0.03, I2=95%) and NT-proBNP (p<0.001, I2=65%) when compared between AF and No-AF groups. Nonetheless, subgroup analysis showed there is no significant difference in pre-operative BNP levels, except in isolated valve surgery (p<0.001), whereas all subgroups showed significantly different pre-operative levels of NT-proBNP.

CONCLUSIONS

Elevated levels of both BNP and NT-proBNP were observed in patients who developed post-operative AF after undergoing cardiac surgery. In particular, pre-operative NT-proBNP levels were elevated in all patients irrespective of the type of surgical procedure, but elevated pre-operative BNP was only seen in valve surgery patients. These findings suggest the potential usefulness of NT-proBNP as a promising biomarker for predicting the occurrence of post-operative AF following cardiac surgery.

The Impact of the Covid-19 Pandemic on Recovery from Cardiac Surgery Over Time: Results of the Cardiaccovid Study from three Uk National Lockdowns

This prospective study (clinicaltrials.gov NCT04366167) explores health-related quality of life (EQ-5D-5L), event-related distress (IES-R) and depression (CES-D) after cardiac surgery during the three UK national COVID-19 lockdowns. Overall, 253 patients participated (lockdown one n = 196; two n = 45; three n = 12) completing the above-mentioned questionnaires at baseline, one week after discharge and six weeks, six and 12 months after surgery. While EQ-5D-5L values were similar across all cohorts, those having surgery in lockdowns two and three had higher IES-R scores at 1-year and higher IES-R and CES-D baseline scores, respectively. Generally, increased distress, worse depression and poorer HRQoL were observed in women.

Open descending and thoracoabdominal aortic replacement: operative steps for patients with prior endovascular treatment

Open surgery remains the gold standard for the treatment of the thoracoabdominal aorta. The rising number of endovascularly treated patients comes with an increase in the number of patients who require secondary open interventions due to the complex nature of the aortic disease or to treat endovascular complications. We describe our current approach to secondary open extent II thoracoabdominal aortic repair in patients with prior endovascular repair. In this case report, we show two different cases that exemplify this scenario.

Fulminant Herpes Pneumonia Postaortic Surgery with Known Ankylosing Spondylitis

Herpes simplex virus (HSV) pneumonitis is rare after cardiac surgery. A 36-year-old gentleman with ankylosing spondylitis underwent emergency surgery for a complex aortic aneurysmal disease. Preoperative treatment of aortitis with antitumor necrosis factor and steroid medication and surgical stress including cardiopulmonary bypass potentially created an immunosuppressive state and reactivation of undiagnosed HSV. Rapid HSV pneumonia ensued, culminating in fulminant organ failure and mortality. HSV pneumonia should be considered postoperatively in patients with severe respiratory distress, especially if immunocompromised.

Retrograde type A aortic dissection: a different evil?

Retrograde type A aortic dissection (RTAAD) can be spontaneous or secondary to the instrumentation of the descending and thoraco-abdominal aorta. It has anatomical differences compared to antegrade type A aortic dissection that impact the management and prognosis. Treatment is not standardized. We report our approach to spontaneous RTAAD in our institution between 2018 and 2022 (n = 15). The mean age was 60.1 years and 93% were male. Aortic valve, coronary arteries and supra-aortic trunks were spared by the dissection in 80% of the cases; distal extension to iliacs was common and lower limb malperfusion was present in 4 cases (27%). The ascending aorta was dilated at presentation in 60% of the cases. Emergency surgery with arch/FET replacement was offered to 11 patients (73%); 3 patients (20%) received a limited proximal aortic repair; 1 patient was treated conservatively. Overall mortality was 47% (100% for limited proximal repair and 22% for those who received arch/FET). We advocate for aggressive treatment of RTAAD excluding the primary entry tear to prevent immediate- and mid-term complications.

Resternotomy aortic root and arch replacement following previous complex type A aortic dissection requiring endovascular repair for malperfusion

A redo sternotomy, aortic root, and arch replacement in a patient following previous complex surgical and endovascular type A aortic dissection repair is presented in this video case report. Shortly after having the initial type A aortic dissection repair with replacement of the ascending aorta, the patient developed severe visceral malperfusion due to a compressed distal true lumen and underwent emergency endovascular repair with ascending arch and descending thoracic aorta stents and chimney grafts for the aortic arch vessels as well as fenestration of the intimal flap of the abdominal aorta. Unfortunately, the patient developed permanent paraplegia and progressive symptomatic severe aortic regurgitation. The patient underwent a redo sternotomy, aortic root, and arch replacement with explantation of the ascending stent graft and chimney stent grafts. Antegrade cerebral perfusion was maintained throughout the procedure. The aortic arch was replaced using a Terumo Aortic Plexus multibranched graft distally anastomosed to the endovascular stent graft, and the innominate and left common carotid arteries were reimplanted onto the graft. The aortic root was replaced with a Bioconduit graft, using a modified Cabrol technique to reimplant the left coronary artery. A satisfactory postoperative course and computed tomography imaging highlight the feasibility of this highly complex aortic arch repair with careful preoperative planning.

THE IMPACT OF THE COVID-19 PANDEMIC ON RECOVERY FROM CARDIAC SURGERY: 1 YEAR OUTCOMES

AIMS

The outbreak of COVID-19 was potentially stressful for everyone, and possibly heightened in those having surgery. We sought to explore the impact of the pandemic on recovery from cardiac surgery.

METHODS AND RESULTS

A prospective observational study of 196 patients who were ≥18years old undergoing cardiac surgery between 23^rd March and 4^th July 2020 (UK lockdown) was conducted. Those too unwell or unable to give consent/complete the questionnaires were excluded. Participants completed (on paper or electronically) the impact of event (IES-R) (distress related to COVID-19), depression (CES-D) and EQ-5D-5L (quality of life, HRQoL) questionnaires at baseline, one week after hospital discharge, and six weeks, six months and 1-year post-surgery.

Questionnaire completion was >75.0% at all timepoints, except at one week (67.3%). Most participants were male (147 (75.0%)), white British (156 (79.6%)) with an average age 63.4years. No patients had COVID-19. IES-R sand CES-D were above average at baseline (indicating higher levels of anxiety and depression) decreasing over time. HRQoL pre-surgery was high, reducing at one week but increasing to almost pre-operative levels at six weeks, and exceeding pre-operative levels at six months and 1-year. IES-R and CES-D scores were consistently higher in women and younger patients with women also having poorer HRQoL up to 1-year after surgery.

CONCLUSION

High levels of distress were observed in patients undergoing cardiac surgery during the COVID-19 pandemic with women and younger participants particularly affected. Psychological support pre- and post-operatively in further crises or traumatic times, should be considered to aid recovery.

REGISTRATION

Clinicaltrials.gov ID:NCT04366167

A multi-centre prospective cohort study of patients on the elective waiting list for cardiac surgery during the COVID-19 pandemic

OBJECTIVES

During the worldwide COVID-19 pandemic, elective cardiac surgery was suspended to provide ICU beds for COVID-19 patients and those requiring urgent cardiac surgery. The aim of this study is to assess the effect of the pandemic on outcomes of patients awaiting elective cardiac surgery.

DESIGN

A multi-centre prospective cohort study.

SETTING

The elective adult cardiac surgery waiting list as of 1 March 2020 across seven UK cardiac surgical centres.

PARTICIPANTS

Patients on the elective adult cardiac surgery waiting list as of 1 March 2020 across seven UK cardiac surgical centres.

MAIN OUTCOME MEASURES

Primary outcome was surgery, percutaneous therapy or death at one year.

METHODS

Data were collected prospectively on patients on the elective adult cardiac surgery waiting list as of 1 March 2020 across seven UK cardiac surgical centres. Primary outcome was surgery, percutaneous therapy or death at one year. Demographic data and outcomes were obtained from local electronic records, anonymised and submitted securely to the lead centre for analysis.

RESULTS

On 1 March 2020, there were 1099 patients on the elective waiting list for cardiac surgery. On 1 March 2021, 83% (n = 916) had met a primary outcome. Of these, 840 (92%) had surgery after a median of 195 (118-262) days on waiting list, 34 (3%) declined an offer of surgery, 23 (3%) had percutaneous intervention, 12 (1%) died, 7 (0.6%) were removed from the waiting list. The remainder of patients, 183 (17%) remained on the elective waiting list.

CONCLUSIONS

This study has shown, for the first time, significant delays to treatment of patients awaiting elective cardiac surgery. Although there was a low risk of mortality or urgent intervention, important unmeasured adverse outcomes such as quality of life or increased perioperative risk may be associated with prolonged waiting times.

Ministernotomy repair of inadvertent proximal right subclavian artery injury following right internal jugular central venous catheter insertion

A man in his 60s was referred for urgent coronary artery bypass grafting (CABG) procedure following acute coronary syndrome. After induction of general anaesthesia, right jugular venous catheterisation under two-dimensional ultrasound guidance was planned as part of perioperative management. While obtaining vascular access, the pulsatile flow was noted once the dilator was inserted, having to abandon the procedure and immediately apply manual pressure. CT angiogram showed proximal right subclavian artery injury with active contrast extravasation and resultant large haematoma in the neck. The patient underwent urgent exploration of the injured vessel through a J-shaped ministernotomy, and primary repair of the artery was performed. The patient recovered from the procedure without any complications. He continued to stay in the hospital for a few days, afterwards, he underwent the initially planned CABG surgery. He was discharged home on day 5 after surgery without further concerns.

Cardiac surgery outcome during the COVID-19 pandemic: a retrospective review of the early experience in nine UK centres

BACKGROUND

Early studies conclude patients with Covid-19 have a high risk of death, but no studies specifically explore cardiac surgery outcome. We investigate UK cardiac surgery outcomes during the early phase of the Covid-19 pandemic.

METHODS

This retrospective observational study included all adult patients undergoing cardiac surgery between 1st March and 30th April 2020 in nine UK centres. Data was obtained and linked locally from the National Institute for Cardiovascular Outcomes Research Adult Cardiac Surgery database, the Intensive Care National Audit and Research Centre database and local electronic systems. The anonymised datasets were analysed by the lead centre. Statistical analysis included descriptive statistics, propensity score matching (PSM), conditional logistic regression and hierarchical quantile regression.

RESULTS

Of 755 included individuals, 53 (7.0%) had Covid-19. Comparing those with and without Covid-19, those with Covid-19 had increased mortality (24.5% v 3.5%, p < 0.0001) and longer post-operative stay (11 days v 6 days, p = 0.001), both of which remained significant after PSM. Patients with a pre-operative Covid-19 diagnosis recovered in a similar way to non-Covid-19 patients. However, those with a post-operative Covid-19 diagnosis remained in hospital for an additional 5 days (12 days v 7 days, p = 0.024) and had a considerably higher mortality rate compared to those with a pre-operative diagnosis (37.1% v 0.0%, p = 0.005).

CONCLUSIONS

To mitigate against the risks of Covid-19, particularly the post-operative burden, robust and effective pre-surgery diagnosis protocols alongside effective strategies to maintain a Covid-19 free environment are needed. Dedicated cardiac surgery hubs could be valuable in achieving safe and continual delivery of cardiac surgery.

Early experience of aortic surgery during the COVID-19 pandemic in the UK: A multicentre study

BACKGROUND

A significant restructuring of the healthcare services has taken place since the declaration of the coronavirus disease 2019 (COVID-19) pandemic, with elective surgery put on hold to concentrate intensive care resources to treat COVID-19 as well as to protect patients who are waiting for relatively low risk surgery from exposure to potentially infected hospital environment.

METHODS

Multicentre study, with 19 participating centers, to define the impact of the pandemic on the provision of aortovascular services and patients' outcomes after having adapted the thresholds for intervention to guarantee access to treatment for emergency and urgent conditions. Retrospective analysis of prospectively collected data, including all patients with aortovascular conditions admitted for surgical or conservative treatment from the 1st March to the 20th May 2020.

RESULTS

A total of 189 patients were analyzed, and 182 underwent surgery. Diagnosis included: aneurysm (45%), acute aortic syndrome (44%), pseudoaneurysm (4%), aortic valve endocarditis (4%), and other (3%). Timing for surgery was: emergency (40%), urgent (34%), or elective (26%). In-hospital mortality was 12%. Thirteen patients were diagnosed with COVID-19 during the peri-operative period, and this subgroup was not associated with a higher mortality.

CONCLUSIONS

There was a significant change in service provision for aortovascular patients in the UK. Although the emergency and urgent surgical activity were maintained, elective treatment was minimal during early months of the pandemic. The preoperative COVID-19 screening protocol, combined with self-isolation and shielding, contributed to the low incidence of COVID-19 in our series and a mortality similar to that of pre-pandemic outcomes.

High Wall Shear Stress can Predict Wall Degradation in Ascending Aortic Aneurysms: An Integrated Biomechanics Study

Background: Blood flow patterns can alter material properties of ascending thoracic aortic aneurysms (ATAA) via vascular wall remodeling. This study examines the relationship between wall shear stress (WSS) obtained from image-based computational modelling with tissue-derived mechanical and microstructural properties of the ATAA wall using segmental analysis. Methods: Ten patients undergoing surgery for ATAA were recruited. Exclusions: bicuspid aortopathy, connective tissue disease. All patients had pre-operative 4-dimensional flow magnetic resonance imaging (4D-MRI), allowing for patient-specific computational fluid dynamics (CFD) analysis and anatomically precise WSS mapping of ATAA regions (6-12 segments per patient). ATAA samples were obtained from surgery and subjected to region-specific tensile and peel testing (matched to WSS segments). Computational pathology was used to characterize elastin/collagen abundance and smooth muscle cell (SMC) count. Results: Elevated values of WSS were predictive of: reduced wall thickness [coef -0.0489, 95% CI (-0.0905, -0.00727), p = 0.022] and dissection energy function (longitudinal) [-15,0, 95% CI (-33.00, -2.98), p = 0.048]. High WSS values also predicted higher ultimate tensile strength [coef 0.136, 95% CI (0 0.001, 0.270), p = 0.048]. Additionally, elevated WSS also predicted a reduction in elastin levels [coef -0.276, 95% (CI -0.531, -0.020), p = 0.035] and lower SMC count ([oef -6.19, 95% CI (-11.41, -0.98), p = 0.021]. WSS was found to have no effect on collagen abundance or circumferential mechanical properties. Conclusions: Our study suggests an association between elevated WSS values and aortic wall degradation in ATAA disease. Further studies might help identify threshold values to predict acute aortic events.

Thoracoabdominal aneurysmectomy: Operative steps for Crawford extent II repair

Background

Open surgical repair remains the gold standard for treatment of thoracoabdominal aortic aneurysm (TAAA). Surgery aims to replace the whole length of the diseased distal aorta while protecting the spinal cord and the visceral organs to limit ischemia-related complications. The substantial associated surgical risks, including death, paraplegia, renal failure requiring permanent dialysis, and respiratory complications leading to prolonged intensive care unit stay, still outweigh the natural history of TAAA with conservative treatment.

Methods

We describe in detail our current approach to open extent II TAAA repair with a step-by-step illustration of the technique and the surgical adjuncts.

Results

We routinely perform left heart bypass with mild passive hypothermia (34°C), cerebrospinal fluid drainage, sequential aortic cross-clamping, monitoring of motor evoked potentials (MEPs) and cerebral, paraspinal, and lower limb oxygen saturation by near-infrared spectrometry, as well as selective visceral perfusion via the celiac and superior mesenteric arteries and renal protection with intermittent administration of Custodiol HTK (histidine-tryptophan-ketoglutarate) solution via the renal arteries. We advocate for individual branch reimplantation using a branched thoracoabdominal graft when possible, and we selectively reattach 1 or more pairs of the lower thoracic intercostal arteries and/or high lumbar arteries, even in the absence of a significant reduction in the MEPs signal. The distal anastomosis is usually constructed above the aortic bifurcation and occasionally to each iliac separately using a bifurcated graft.

Conclusions

Favorable early outcomes and a durable TAAA repair can be achieved at experienced high-volume centers with standardized preoperative selection and multidisciplinary team-based intraoperative and postoperative management of these patients.

Intermediate and high peri-operative cardiac enzyme release following isolated coronary artery bypass surgery are independently associated with higher one-year mortality

Background

The relationship between cardiac enzyme (CE) release following coronary artery bypass surgery (CABG) and medium term outcome is unclear. We sought to determine the relationship between post-operative CE release and one-year survival following isolated CABG.

Methods

Over three years 3,024 consecutive patients underwent isolated CABG. Patient characteristics were prospectively recorded in a cardiac surgical database. CE release, taken as the highest single measurement recorded in the first 24 hours post-op, was abstracted from an electronic archive. All cause mortality was taken from a national registry of deaths.

Results

Data were complete for 2,860 (94.6%) patients. CK-MB isoenzyme (reference range 5–24 U/l) was recorded in 2,568 (89.8%), total CK in 292 (10.2%).

CE release three or more times the upper limit of the reference range (ULR) were recorded in 498 (17.4%) patients, 163 (5.7%) patients had CE more than six times ULR. There were 122 deaths (4.3%). Cox proportional hazards analysis showed that CE release 3–6 times ULR (adjusted HR 2.1 [95% CI: 1.6 to 2.6], p = 0.002) and CE release six or more times the ULR (adjusted HR 5.0 [95% CI: 4.5 to 5.4], p < 0.001) were independently associated with increased one-year mortality.

Conclusion

Cardiac enzyme release following CABG is associated with increased one-year all-cause mortality. The definition of peri-operative myocardial infarction following CABG should include elevation of CK-MB three or more times the upper limit of normal.

Does prophylactic sotalol and magnesium decrease the incidence of atrial fibrillation following coronary artery bypass surgery: a propensity-matched analysis

Background

Atrial fibrillation can occur in up to 40% of patients undergoing coronary surgery.

Methods

We retrospectively analysed 103 consecutive coronary surgery patients under the care of one surgeon between April 2003 and September 2003. These patients received 40 mg of sotalol orally twice daily from the first post-operative day for 6 weeks and 2 g of magnesium intravenously immediately post surgery and on the first post-operative day. We developed a propensity score for the probability of receiving sotalol and magnesium after coronary surgery. 89 patients from the sotalol and magnesium group were successfully matched with 89 unique coronary surgery patients who did not receive either sotalol or magnesium with an identical propensity score.

Results

Preoperative characteristics were well matched between groups. There was no significant difference with respect to in-hospital mortality between groups (sotalol and magnesium 1.1% versus control 4.5%; p = 0.17). The incidence of atrial fibrillation in the sotalol and magnesium group was 13.5% compared to 27.0% in the controls (p = 0.025).

Conclusion

The combination of sotalol and magnesium can significantly reduce the incidence of post-operative atrial fibrillation following coronary surgery.

A survey of current myocardial protection practices during coronary artery bypass grafting

OBJECTIVE

To identify current myocardial protection strategies for coronary artery bypass grafting (CABG) across the UK and Ireland.

METHODS

A questionnaire survey of 15 questions was sent to practising cardiac surgeons between June and October 2002. The list of surgeons was obtained from the Society of Cardiothoracic Surgeons of Great Britain and Ireland database and they were contacted by postal and electronic mail.

RESULTS

118 (73.7%) out of 160 surgeons responded to the survey. 61 (51.7%) perform CABG on-pump (ONCAB) while 10 (8.5%) practice off-pump CABG (OPCAB). 47 (39.8%) perform either depending on individual cases. Of the 108 surgeons performing ONCAB, 91 (84.3%) use cardioplegia while 17 (15.7%) use cross-clamp and fibrillation techniques. Of those using cardioplegia, 76 (83.5%) use blood cardioplegia, 15 (19.7%) use warm-blood and 60 (78.9%) use cold-blood cardioplegia. 15(16.5%) use crystalloid cardioplegia. Retrograde cardioplegia is used by 23 (25.2%). We find an interesting variation of practice in relation to specifics like warm induction, graft cardioplegia, hot-shot, single cross-clamp, hypothermia and venting procedures. An overwhelming majority of surgeons performing OPCAB use the Octopus stabiliser (n=44, 77.2%) with some others preferring the Genzyme system. Supplementary stabilisation is not commonly used. While most OPCAB surgeons use intracoronary shunts (n=51), some prefer blockers (n=9) and others use coronary sloops (n=36). Ischaemic preconditioning is not commonly practised. Several surgeons have changed their practice of myocardial protection in the last 5 years (n=45).

CONCLUSIONS

This survey gives us an interesting insight into current myocardial protection practices in the UK and Ireland and may be useful for future reference.

Effect of Smoking Status on Mortality and Morbidity Following Coronary Artery Bypass Surgery

BACKGROUND

We aimed to examine the effect of smoking on outcomes following coronary artery bypass grafting (CABG).

METHODS

We retrospectively analysed 6 367 consecutive patients who underwent CABG between April 1997 and March 2003. Logistic regression was used to risk adjust in-hospital outcomes, while Cox proportional hazards analysis was used to risk adjust Kaplan-Meier survival curves. Outcomes were adjusted for variables suggested by the American Heart Association and American College of Cardiology.

RESULTS

947 (14.9 %) patients were current smokers (smoking within 1 month of surgery), while 3857 (60.6 %) were ex-smokers and 1 563 (24.5 %) were non-smokers. After adjusting for differences in case-mix, current smokers were more likely to develop chest infections ( p < 0.001), atelectasis ( p < 0.001), and require ventilation longer than 48 hours ( p = 0.003). Current smokers were also more likely to stay in intensive care for more than 3 days ( p < 0.001). Ex-smokers were not associated with excess mortality ( p = 0.11), while current smokers had significantly increased mortality during follow-up ( p = 0.029).

CONCLUSIONS

Patients should be encouraged to stop smoking to maximise the long-term benefits of CABG.

Einfluss des Rauchens auf die Ergebnisse der koronaren Bypasschirurgie

BACKGROUND AND PURPOSE

The proportion of patients undergoing coronary artery bypass surgery (CABG) with a history of smoking is increasing. The aim of this study was to examine the effect of smoking on outcomes following CABG.

PATIENTS AND METHODS

6,367 consecutive patients who underwent CABG between April 1997 and March 2003 were analyzed retrospectively. Logistic regression was used to risk-adjust inhospital outcomes, while Cox proportional hazards analysis was used to risk-adjust Kaplan-Meier survival curves. Outcomes were adjusted for variables suggested by the American Heart Association and the American College of Cardiology.

RESULTS

947 patients (14.9%) were current smokers (smoking within 1 month of surgery), while 3,857 (60.6%) were ex-smokers and 1,563 (24.5%) nonsmokers. After adjusting for differences in case-mix, current smokers were more likely to develop chest infections (p < 0.001), atelectasis (p < 0.001), and require ventilation > 48 h (p = 0.003). Current smokers were also more likely to stay in intensive care for > 3 days (p < 0.001). There was no association between smoking status and in-hospital mortality. Ex-smokers were not associated with excess mortality (p = 0.11), while current smokers had significantly increased mortality during follow-up (p = 0.029).

CONCLUSION

Current smokers are associated with increased respiratory complications, and prolonged stay on intensive care. Although not associated with in-hospital mortality, there appears to be a significant increase in mortality in smokers during a 4-year follow-up period. Patients should be encouraged to stop smoking to maximize the long-term benefits of CABG.

Bullectomy for chronic obstructive pulmonary disease

Chronic obstructive pulmonary disease is a progressive, disabling condition which leads to poor quality of life and limited survival. Over the years, a variety of surgical procedures have been used to achieve symptomatic improvement in selected patients. This article gives a historical account of these interventions and looks at current surgical options, both for primary treatment and management of complications.