[Show abstract][Hide abstract] ABSTRACT: We present a case of surgical implantation of biventricular epicardial pacing leads and a defibrillating patch via lower half mini sternotomy. Although median sternotomy is routinely used for this purpose, lower half mini sternotomy could provide the surgeon with the same surgical field exposure and a faster post operative recovery.
Journal of Cardiothoracic Surgery 01/2013; 8(1):5. · 0.90 Impact Factor
[Show abstract][Hide abstract] ABSTRACT: A best evidence topic was written according to a structured protocol. The question addressed was 'is the saphenous vein graft or right gastroepiploic artery a better conduit for revascularization of the right coronary artery?' One hundred and five articles were found using a designated search, of which 10 articles were found to represent the best available evidence to answer the clinical question. Of these 10 articles, two were reports of a randomized controlled trial and represented the highest level of evidence, whereas eight articles were retrospective observational studies. All were published between 2002 and 2012. Outcome measures varied considerably, but mostly included graft patency at varying periods of follow-up. The randomized evidence suggested that the saphenous vein had better early (6-month) and mid-term (3-year) graft patency than the right gastroepiploic artery when used for right coronary artery revascularization. The use of the saphenous vein was also found to be predictive of superior graft function using multivariate regression; however, a more recent propensity score analysis identified gastroepiploic-right coronary grafts to yield superior very long-term (>10 years) clinical outcomes. Overall, based on the best quality evidence and in view of technical limitations and flow characteristics of the right gastroepiploic artery, it appears that saphenous vein grafts may offer superior outcomes for revascularization of the right coronary artery in most cases, and should be preferentially used.
Interactive Cardiovascular and Thoracic Surgery 07/2012; 15(5):888-92. · 1.11 Impact Factor
[Show abstract][Hide abstract] ABSTRACT: A best evidence topic was written according to a structured protocol. The question addressed was whether the right internal thoracic artery (RITA) provides a superior outcome for revascularization of the right coronary artery (RCA) compared with the saphenous vein graft (SVG). Using a designated search strategy, 226 articles were found, of which five represented the best available evidence. The authors, journal, date, country of publication, study type, patient group studied, relevant outcomes and results were tabulated. Of these five studies, one offered level I evidence (data from a randomized trial) and four were level II studies (reports of observational data). The outcome measures varied considerably, but most included graft patency at varying levels of the follow-up. The randomized data showed strong evidence favouring the SVG, mainly in terms of mid-term patency. With the exception of a large cohort study that demonstrated the superior patency of the RITA compared with the SVG in the right coronary territory, the observational studies showed better results for SVG in graft patency, reintervention and cardiovascular complication rate. Overall, and in view of the methodological limitations and the different weight of evidence among studies, it appears that the SVG may offer a superior outcome for revascularization of the RCA when compared with the RITA.
Interactive Cardiovascular and Thoracic Surgery 05/2012; 15(2):244-7. · 1.11 Impact Factor
[Show abstract][Hide abstract] ABSTRACT: Optimal thromboprophylaxis following bioprosthetic aortic valve replacement (AVR) remains controversial. The main objective, which is the effective prevention of central nervous or peripheral embolic events, especially in the early postoperative period, will have to be weighed against the haemorrhagic risk that is associated with the utilization of different antithrombotic regimes. Most governing bodies in cardiovascular medicine have issued recommendations on thromboprophylaxis after the surgical implantation of aortic bioprostheses. However, the level of evidence to support these recommendations remains low, largely due to the inherent limitations of conducting appropriately randomized and adequately powered clinical research in this area. It is apparent from the recent surveys and large registries that there is a great variability in antithrombotic practice at an institutional or individual-clinician level reflecting this controversy and the lack of robust evidence. While organizational, financial or conceptual limitations could hinder the conduct and availability of conclusive research on optimal thromboprophylaxis after aortic bioprosthesis, it is imperative that all evidence is presented in a systematic way in order to assist the decision-making for the modern clinician. In this review, we provide an outline of the current recommendations for thromboprophylaxis, followed by a comprehensive and analytical presentation of all comparative studies examining anticoagulation vs. antiplatelet therapy after bioprosthetic AVR.
Interactive Cardiovascular and Thoracic Surgery 04/2012; 15(1):109-14. · 1.11 Impact Factor
[Show abstract][Hide abstract] ABSTRACT: A best evidence topic in cardiac surgery was written according to a structured protocol. The question addressed was what the optimal intraoperative anticoagulation strategy should be in patients undergoing off-pump coronary artery bypass graft (CABG) surgery. A total of 157 papers were identified using the reported search, of which 8 were judged to represent the best evidence. The authors, journal, date, country of publication, study type, patient group studied, relevant outcomes and results were tabulated. The quality of clinical trials was assessed. Off-pump CABG is currently considered as a safe and effective alternative to CABG with the use of cardiopulmonary bypass, especially in the presence of off-pump expertise and certain pathologies. Although most technical steps in off-pump revascularization are standardized, it appears that there is inconsistency in intraoperative anticoagulation practice. Surveys conducted in the USA and Europe confirm the lack of uniform policy, with heparin dose ranging between 70 and 500 U/kg and from full-dose protamine to no reversal of anticoagulation. Although the quality of evidence is low, there is a trend for utilization of heparin at 150 U/kg, followed by half-dose protamine reversal, which appears to provide adequate anticoagulation for the safe conduct of anastomoses and thromboprophylaxis without significantly increasing the risk of postoperative bleeding. However, more research is necessary before firm recommendations can be made.
Interactive Cardiovascular and Thoracic Surgery 02/2012; 14(5):629-33. · 1.11 Impact Factor
[Show abstract][Hide abstract] ABSTRACT: Vacuum-assisted closure (VAC) has recently been adopted as an acceptable modality for management of sternotomy wound infections. Although generally efficacious, the use of negative pressure devices has been associated with complications such as bleeding, retention of sponge, and empyema. We report the first case of greater omental hernia as a rare complication of vacuum-assisted closure of sternal wound infection following coronary artery bypass grafting.
[Show abstract][Hide abstract] ABSTRACT: Surgical repair of ascending aortic disease involving the aortic root most commonly involves the direct ana stomosis of the coronary ostia to the composite aortic graft. Occasionally, when direct aortocoronary ana stomosis is not safe or technically challenging--such as in cases of extreme aortic dilatation, calcification and reoperations--the Cabrol technique and its modification can provide a safe and effective alternative. As the Cabrol is often reserved as a second line or bailout procedure, there is insufficient evidence to support the optimal imaging assessment and follow up of patients who have undergone this complex aortic recon struction. We present the case of a patient where emergency replacement of the aortic root took place with a modified Cabrol aortocoronary anastomosis. We discuss the usefulness, findings and limitations of modern noninvasive imaging modalities that can provide a complete functional and anatomical assessment of this surgical technique.
[Show abstract][Hide abstract] ABSTRACT: Postoperative atrial fibrillation (POAF) affects approximately 30% of patients undergoing elective cardiac surgery. While its pathogenesis is multifactorial, increasing evidence supports a role for oxidative stress in the electrophysiological remodelling associated with AF. Although prophylactic antioxidants appear to be a potentially attractive pharmacotherapy, there is still uncertainty regarding their efficacy. This study aims to provide a quantitative summary of the current evidence surrounding antioxidant vitamins and POAF prevention.
A systematic literature review identified five randomised controlled trials incorporating 567 patients (n = 284 antioxidant, n = 283 control). These were meta-analysed using random effects modelling. Heterogeneity, subgroup analysis, quality scoring and risk of bias were assessed. Primary endpoints were the incidence of POAF and all-cause arrhythmia. Secondary endpoints were length of stay in the intensive care unit (ITU) and length of hospital stay.
Vitamins C and E significantly reduced the incidence of POAF (OR 0.43, 95% CI 0.21 to 0.89) and all-cause arrhythmia (OR 0.54, 95% CI 0.29 to 0.99) compared with controls. A significant reduction in both ITU stay (weighted mean difference (WMD) -0.44, 95% CI -0.70 to -0.17) and hospital stay (WMD -1.11, 95% CI -1.70 to -0.52) was also seen in the antioxidant group, without significant heterogeneity.
The prophylactic use of vitamins C and E may significantly reduce the incidence of POAF and all-cause arrhythmia following cardiac surgery. However, the overall quality of current studies is poor and further research should focus on adequately powered randomised controlled trials that standardise AF reporting, antioxidant protocol and the use of concomitant agents. Cost analysis should be considered to establish the potential economic benefit of antioxidant vitamin prophylaxis in POAF.
[Show abstract][Hide abstract] ABSTRACT: Atrial fibrillation (AF) is an important cause of morbidity and mortality after cardiac surgery. The pathogenesis of AF appears to be multifactorial but little is known about the cause-effect relationship of substrate modifications with the onset of the arrhythmia. With the use of modern proteomics, this study aims to identify preexisting changes in the left atrium of patients susceptible to postoperative AF.
We analyzed 20 matched patients undergoing elective, first-time coronary artery bypass grafting with no history of AF. They were divided into 2 equal groups according to the development of postoperative AF. Proteomic analysis was performed in left atrial tissue obtained during surgery using two-dimensional difference in gel electrophoresis techniques. Mass spectrometry identified proteins that were differentially expressed in patients who developed AF against those who remained in sinus rhythm.
Proteomic analysis of left atrial tissue identified 19 differentially expressed protein spots between patients who developed postoperative AF and their sinus rhythm counterparts. In patients who developed AF, proteins associated with oxidative stress and apoptosis (peroxiredoxin 1, apoptosis-inducing factor, and 96S protease regulatory subunit 8) as well as acute phase response components (apolipoprotein A-I, fibrinogen) were found to be increased. Conversely, the expression of proteins responsible for glycolysis (enolase) and pyruvate metabolism (pyruvate dehydrogenase) was reduced.
We describe protein changes that precede the development of postoperative AF and which might be suggestive of increased oxidative stress and glycolytic inhibition in the left atrium of patients predilected to AF.
The Annals of thoracic surgery 07/2011; 92(1):104-10. · 3.45 Impact Factor
[Show abstract][Hide abstract] ABSTRACT: Coronary artery bypass surgery can offer excellent results when performed with cardiopulmonary bypass (on pump) or without cardiopulmonary bypass (off pump). The debate as to which technique is superior remains unanswered. Intra-operative conversion from off- to on-pump coronary surgery is a relatively unexplored phenomenon, which cannot be assessed within randomised controlled trial design. We aimed to assess the effect of off-pump conversion on patient mortality. Medline, Embase, Cochrane and Google Scholar databases were systematically reviewed for studies published between 1980 and 2010 that compared the incidence of mortality between converted and non-converted off-pump patients. Publication bias and heterogeneity were assessed and data were extracted independently by multiple observers. We undertook a meta-analysis of these studies using random effects modelling. A total of 17 studies fulfilled our inclusion criteria, containing data for 18,870 off-pump coronary artery bypass operations spanning a decade (1998-2008), involving 920 cases of conversion. Overall, conversion increased mortality by an odds ratio of 6.18 (95% confidence interval 4.65-8.20), whereas emergency conversion further raised the odds ratio of mortality to 6.99 (95% confidence interval 5.18-9.45). The conversion from off- to on-pump cardiac surgery may significantly increase the chance of an adverse outcome, whereas emergency conversion confers a significant rise in mortality. The risk of conversion should be discussed when obtaining the patient's informed consent and its prevention warrants serious consideration by cardiac surgeons and cardiac surgical training programmes.
European journal of cardio-thoracic surgery: official journal of the European Association for Cardio-thoracic Surgery 06/2011; 41(2):291-9. · 2.40 Impact Factor
[Show abstract][Hide abstract] ABSTRACT: A best evidence topic in cardiac surgery was written according to a structured protocol. The question addressed was whether prophylactic therapy with antioxidant vitamins reduces the incidence of postoperative atrial fibrillation (AF). One hundred and fifty-four papers were found using the reported search, of which five were judged to represent the best evidence to answer the question. The authors, journal, date, country of publication, patient group studied, study type, relevant outcomes and results were tabulated. Four of the five studies found antioxidant vitamins to significantly reduce the incidence of postoperative AF. Two of the studies show that prophylactic treatment with adjuvant vitamin C and β-blockers is more effective than β-blocker therapy alone. The quality of these studies was assessed using a Jadad scoring system, which identified four of the studies to be of low and one to be of high methodological quality. We conclude that although preliminary evidence suggests that prophylactic antioxidant vitamins may be effective in reducing the incidence of postoperative AF, there is a lack of high-quality data. Additional large-scale, adequately powered clinical studies are warranted before antioxidant vitamins can be considered for routine use in this setting.
Interactive Cardiovascular and Thoracic Surgery 06/2011; 13(1):82-5. · 1.11 Impact Factor
[Show abstract][Hide abstract] ABSTRACT: Co-existent mitral regurgitation may adversely influence both morbidity and mortality in patients undergoing aortic valve replacement for severe aortic stenosis. Whilst it is accepted that concomitant mitral intervention is required in severe, symptomatic mitral regurgitation, in cases of mild-moderate non-structural mitral regurgitation, improvement may be seen following aortic valve replacement alone, avoiding the increased risk of double-valve surgery. The exact benefit of such a conservative approach is, however, yet to be adequately quantified. We performed a systematic literature review identifying 17 studies incorporating 3053 patients undergoing aortic valve replacement for aortic stenosis with co-existing mitral regurgitation. These were meta-analysed using random effects modelling. Heterogeneity and subgroup analysis were assessed. Primary end points were change in mitral regurgitation severity and 30-day, 3-, 5- and 10-year mortality. Secondary end points were end-organ dysfunction (neurovascular, renal and respiratory), and the extent of ventricular remodelling following aortic valve replacement. Our results revealed improvement in the severity of mitral regurgitation following aortic valve replacement in 55.5% of patients, whereas 37.7% remained unchanged, and 6.8% worsened. No significant difference was seen between overall data and either the functional or moderate subgroups. The overall 30-day mortality following aortic valve replacement was 5%. This was significantly higher in moderate-severe mitral regurgitation than nil-mild mitral regurgitation both overall (p=0.002) and in the functional subgroup (p=0.004). Improved long-term survival was seen at 3, 5 and 10 years in nil-mild mitral regurgitation when compared with moderate-severe mitral regurgitation in all groups (overall p<0.0001, p<0.00001 and p=0.02, respectively). The relative risk of respiratory, renal and neurovascular complications were 7%, 6% and 4%, respectively. Reverse remodelling was demonstrated by a significant reduction in left-ventricular end-diastolic diameter and left-ventricular mass (p=0.0007 and 0.01, respectively), without significant heterogeneity. No significant change was seen in left-ventricular end-systolic diameter (p=0.10), septal thickness (p=0.17) or left atrial area (p=0.23). We conclude that despite reverse remodelling, concomitant moderate-severe mitral regurgitation adversely affects both early and late mortality following aortic valve replacement. Concomitant mitral intervention should therefore be considered in the presence of moderate mitral regurgitation, independent of the aetiology.
European journal of cardio-thoracic surgery: official journal of the European Association for Cardio-thoracic Surgery 05/2011; 40(5):1087-96. · 2.40 Impact Factor
[Show abstract][Hide abstract] ABSTRACT: Fundamental research into molecular mechanisms of atrial fibrillation (AF) and improved understanding of processes involved in the initiation and maintenance of AF have transformed the traditional approach to its management by targeting only the electrical aspects, usually with antiarrhythmic drugs and, recently, by ablation. The antiarrhythmic potential of upstream therapies, such as angiotensin-converting enzyme inhibitors, angiotensin receptor blockers (ARBs), statins, and n-3 (ω-3) polyunsaturated fatty acids, extends beyond the benefit of treating underlying heart disease to modifying the atrial substrate and intervening in specific mechanisms of AF. The key target is structural remodelling of the atria, particularly inflammation and fibrosis, although there is evidence to suggest the direct involvement at the ion channel level. Positive clinical reports supported by robust experimental data have suggested that upstream therapies can be valuable strategies for primary prevention of AF in selected patients and have resulted in several class IIA recommendations in the new European guidelines on AF. However, these results have not been consistently replicated in the secondary prevention setting, and several recent randomized controlled studies failed to demonstrate any effect of upstream therapies on AF burden or on major cardiovascular outcomes. Part II of the review summarizes the evidence base for the use of upstream therapies for secondary prevention of AF.
[Show abstract][Hide abstract] ABSTRACT: Operations on the proximal aorta for aneurysms and dissections almost invariably involve the use of an aortic conduit. The optimal method for safe and effective conduit to the coronary anastomosis has been a matter for debate. Although the modified Bentall procedure with use of ostial aortic "buttons" may provide superior results and currently constitutes the standard of care for aortic root reconstruction, anatomic difficulties such as the closeness of the ostia to the aortic annulus, extreme aortic dilatation/calcification, and reoperations, may hinder the safe and tension-free conduit to the coronary anastomosis. In this technical review we examine the evolution of the Cabrol technique and its modifications, as well as its current indications and related outcomes.
The Annals of thoracic surgery 03/2011; 91(5):1636-41. · 3.45 Impact Factor
[Show abstract][Hide abstract] ABSTRACT: Atrial fibrillation (AF) is associated with significant morbidity and mortality. It is also a progressive disease secondary to continuous structural remodelling of the atria due to AF itself, to changes associated with ageing, and to deterioration of underlying heart disease. Current management aims at preventing the recurrence of AF and its consequences (secondary prevention) and includes risk assessment and prevention of stroke, ventricular rate control, and rhythm control therapies including antiarrhythmic drugs and catheter or surgical ablation. The concept of primary prevention of AF with interventions targeting the development of substrate and modifying risk factors for AF has emerged as a result of recent experiments that suggested novel targets for mechanism-based therapies. Upstream therapy refers to the use of non-antiarrhythmic drugs that modify the atrial substrate- or target-specific mechanisms of AF to prevent the occurrence or recurrence of the arrhythmia. Such agents include angiotensin-converting enzyme inhibitors (ACEIs), angiotensin receptor blockers (ARBs), statins, n-3 (ω-3) polyunsaturated fatty acids, and possibly corticosteroids. Animal experiments have compellingly demonstrated the protective effect of these agents against electrical and structural atrial remodelling in association with AF. The key targets of upstream therapy are structural changes in the atria, such as fibrosis, hypertrophy, inflammation, and oxidative stress, but direct and indirect effects on atrial ion channels, gap junctions, and calcium handling are also applied. Although there have been no formal randomized controlled studies (RCTs) in the primary prevention setting, retrospective analyses and reports from the studies in which AF was a pre-specified secondary endpoint have shown a sustained reduction in new-onset AF with ACEIs and ARBs in patients with significant underlying heart disease (e.g. left ventricular dysfunction and hypertrophy), and in the incidence of AF after cardiac surgery in patients treated with statins. In the secondary prevention setting, the results with upstream therapies are significantly less encouraging. Although the results of hypothesis-generating small clinical studies or retrospective analyses in selected patient categories have been positive, larger prospective RCTs have yielded controversial, mostly negative, results. Notably, the controversy exists on whether upstream therapy may impact mortality and major non-fatal cardiovascular events in patients with AF. This has been addressed in retrospective analyses and large prospective RCTs, but the results remain inconclusive pending further reports. This review provides a contemporary evidence-based insight into the role of upstream therapies in primary (Part I) and secondary (Part II) prevention of AF.
[Show abstract][Hide abstract] ABSTRACT: Preoperative left ventricular systolic function is an important prognostic factor in patients undergoing mitral valve surgery. Preoperative myocardial deformation may be impaired without reduction in conventional indices such as ejection fraction (EF). Strain rate (SR) imaging is very sensitive in detecting regional systolic abnormalities and might allow diagnosis of subclinical changes in systolic left ventricular (LV) function before surgery. We aimed to investigate the value of preoperative regional myocardial peak systolic SR as a predictor of postoperative LV systolic function in patients with severe mitral regurgitation (MR) undergoing surgery.
A total of 62 patients (age 52±12) with chronic severe MR, who underwent mitral valve repair, were studied. A standard echo examination, extended with tissue Doppler, was performed before and at 12 months after surgery. For the evaluation of longitudinal function, mid-ventricular segment shortening was analysed for the septum, LV lateral wall and anterior and inferior walls.
Patients were divided into two groups based on postoperative EF: group 1 with EF(post-op)>50% and group 2 with EF(post-op)<50%. Group 1 had a significantly (p=0.004) higher preoperative SR (LV lateral wall: -1.97±0.26s(-1); septum: -1.74±0.31s(-1); anterior wall: -1.94±0.30s(-1), inferior wall: -1.93±0.29s(-1)) compared to group 2 (LV lateral wall: -0.98±0.23s(-1); septum: -0.98±0.26s(-1); anterior wall: -0.94±0.30s(-1), inferior wall: -1.00±0.24s(-1)). When SR was corrected for size, the SR/EDV index (EDV is end diastolic volume) also showed significant changes (p=0.0007) at baseline between the groups. For detecting subclinical changes in deformation of the LV lateral wall, a cut-off value of the SR/EDV index<0.006 had 89% sensitivity and 93% specificity; for the anterior wall, SR/EDV index<0.005 had 88% sensitivity and 94% specificity.
SR imaging (corrected for geometry) can detect abnormalities in LV function at subclinical levels in patients with severe mitral regurgitation.
European journal of cardio-thoracic surgery: official journal of the European Association for Cardio-thoracic Surgery 03/2011; 40(5):1131-7. · 2.40 Impact Factor
[Show abstract][Hide abstract] ABSTRACT: The Cabrol technique is reserved where the conventional 'button' or Bentall techniques fail to maintain a tension-free anastomosis between the coronary arteries and aortic conduit. However, the side-to-side anastomosis of the interposition graft that connects the coronary ostia with the aorta in the Cabrol, may lead to kinking or tension, and subsequent occlusion. We present a case of successful Cabrol modification in a patient with bicuspid aortopathy where the graft to the right coronary artery was anastomosed directly onto the valved conduit and the graft to the left main stem onto the previous right aortocoronary graft in a T-fashion.
Interactive Cardiovascular and Thoracic Surgery 02/2011; 12(2):199-201. · 1.11 Impact Factor
[Show abstract][Hide abstract] ABSTRACT: Thrombotic occlusion of saphenous vein grafts (SVG), the conduits most commonly used in coronary artery bypass grafting (CABG) surgery, causes significant morbidity and mortality. There is class 1A evidence that early aspirin administration following CABG reduces thrombotic SVG occlusion, as well as overall morbidity and mortality. The American Heart Association/American College of Cardiology and the European Association of Cardiothoracic Surgeons have issued guidelines recommending that 150 to 325 mg aspirin be administered within 6 hours following CABG. We carried out a clinical audit of our practice to identify any reasons for deviation from these standards of care and to implement any corrective measures. We prospectively collected data on 200 consecutive patients who underwent CABG to assess both the compliance in prescribing and administering aspirin and the effect on blood loss and transfusion requirements. Sixty-nine percent of patients received an aspirin loading dose 6 hours postoperatively. The reasons for nonadministration of aspirin were postoperative bleeding (10%), lack of a prescription despite aspirin being clinically indicated (13%), and a prescription for aspirin but no administration (9%). Reasons included inadequate handover between clinical teams (4%), aspirin loading ≤24 hours preoperatively (2%), and administration after the first 6 hours (3%). Our audit showed that early aspirin administration did not cause further bleeding or increase blood or blood product transfusion. We followed the recommendations in the majority of cases, but there is scope for improvement in this practice and a need to address "gray areas" not covered by the guidelines.
Heart Surgery Forum 02/2011; 14(1):E7-E11. · 0.63 Impact Factor