How effective is unipolar radiofrequency ablation for atrial fibrillation during concomitant cardiac surgery?

A best evidence topic in cardiothoracic surgery was written according to a structured protocol. The question addressed was whether in patients undergoing cardiac surgery, concomitant unipolar radiofrequency ablation had a sufficiently acceptable success rate to justify the additional procedure. A total of 256 papers were found using the reported search; of which, 9 represented the best evidence to answer the clinical question. The authors, journal, date and country of publication, patient group studied, study type, relevant outcomes and results of these papers were tabulated. Major exclusion criteria included studies using bipolar ablation, ambiguous or unspecified ablation techniques, other energy modalities and studies with highly variable or undisclosed follow-up time. All of the studies showed concomitant unipolar ablation to have an acceptable success rate in restoring patients to sinus rhythm (SR), with follow-ups ranging from 12 months to 5 years. At 12-month follow-up, one study showed that this rate was as high as 83%. Ablations were more likely to be successful in patients with paroxysmal or persistent atrial fibrillation (AF) as defined by ACC/AHA/ESC criteria. One paper showed that paroxysmal/persistent AF at baseline was predictive of likely success of ablation in patients with permanent AF (P = 0.0004). Restoration and maintenance of SR after ablation was not significantly affected by the type of cardiac surgery performed (P = 0.262). Unipolar ablation does have limitations such as high tissue temperature and no predictable transmurality. However, it appears to compare favourably in the long term to energy modalities such as microwave. The lack of level I evidence was a major drawback in the analysis, as was the lack of continuous electrocardiogram monitoring in the methodology of the studies. Figures quoted from the data could therefore be under-representations of the true instances of AF recurrence. With the current evidence, concomitant ablation to treat AF during cardiac surgery appears safe in terms of adding no additional risks, and effective at restoring SR regardless of the type of cardiac surgery. This is particularly true of younger patients with paroxysmal or persistent AF and those with smaller atrial diameters.

Is Health Care a Right? Health Reforms in the USA and their Impact Upon the Concept of Care

In 2008 United States President Barack Obama declared that health care “should be a right for every American”.¹ This statement, although noble, does not reflect US healthcare statistics in recent times, with the number of uninsured reaching over 50 million in 2010.² Such disparity has sparked a political drive towards change, and the introduction of the Patient Protection and Affordable Care Act (PPACA).³ These changes have been highly polemical, raising the fundamental question of whether health care is a right; a contract between the nation and its inhabitants granted at birth, or an entitlement; a privilege that must be earned as opposed to universally provided.

Access to healthcare in the US is mediated by insurance coverage, either in the form of private or employer based cover, which may be government based for public sector employees or private for private sector employees. The majority of spending on healthcare however, comes from government expenditure on health programs such as Medicare, Medicaid, Tricare, and the State Children's Health Insurance Program (SCHIP).⁴ Medicare is a federal government funded social insurance program that provides health insurance to people aged 65 and older, younger people with disabilities, and those with end stage renal failure requiring dialysis. Medicaid is a means tested insurance coverage program for individuals with low incomes and their families, and is jointly funded by state and federal governments. Tricare is a healthcare program that provides healthcare insurance for military personnel, retirees, and their dependents. The SCHIP provides states with federal government funding to provide health insurance to children from families with modest incomes that do not qualify for Medicaid. As such, although the majority of the US population is insured by federal, state, employer, or private health insurance, the remainders go uninsured.

A review of the evidence for and against thromboprophylaxis in total hip replacement

Deep vein thrombosis (DVT) after an unprotected total hip replacement (THR) is common and this review explores the balance between risks and benefits of thrombo-prophylaxis in protecting patients undergoing THR. A literature search for English publications was conducted on Medline & PubMed. Governance bodies and their guidelines were consulted. MESH terms included Deep Vein Thrombosis OR DVT AND Prophylaxis AND Hip AND/OR Surgery AND/OR Total Replacement OR Arthroplasty. THR results in significant risk of thrombo-embolic complications with studies showing that as many as one half of patients suffer from DVT post-operatively. Prophylactic treatments are used to reduce the incidence of DVT. However, there are also risks associated with the use of prophylaxis, including excessive bleeding and major cardio-vascular events. Further investigation is required to determine which patients should be given what prophylaxis and for how long post THR.

Is it safe to stop anticoagulants after successful surgery for atrial fibrillation?

A best evidence topic in cardiothoracic surgery was written according to a structured protocol. The question addressed was: is it safe to stop anticoagulants after successful surgery for atrial fibrillation? Altogether, 177 papers were found using the reported search, of which 14 were selected that represented the best evidence to answer the clinical question. Selection criteria included study relevance, primary outcome, size of study population and length of follow-up. The authors, journal, date and country of publication, patient group studied, study type, relevant outcomes and results of these papers are tabulated. The weight of evidence, including over 10,000 patient-years of follow-up, supports the discontinuation of warfarin following atrial fibrillation correction procedures as being safe, with an associated annual thromboembolic stroke rate of 0-3.8% off warfarin, in studies where warfarin was stopped at a mean of 3.6 months (range 0-8 months) after the procedure. However, the confidence of this conclusion suffers from a paucity of high-quality randomized controlled trials in the field, with the main body of evidence coming instead from observational non-randomized studies. The stroke rate also varies with the exact procedure performed; pulmonary vein isolation procedures are the most extensively evaluated and carry the lowest stroke rate following warfarin discontinuation (0-0.4% per annum when performed as an isolated procedure). By contrast, left atrial appendage occlusion by insertion of a transcatheter device has an associated annual stroke rate of 0-3.8% off warfarin. Thus, discontinuation of warfarin following such transcatheter procedures cannot be recommended at this time. Concomitant heart surgeries, such as mitral valve repair have been shown to increase the thromboembolic rate both unpredictably and dramatically, and this review thus identifies concomitant mitral valve surgery as a potentially substantial risk factor for late thromboembolic stroke in patients undergoing corrective surgeries for atrial fibrillation. This review finds in favour of warfarin discontinuation in selected patients at three months post-procedure, emphasizing consideration of the patient's individual risk-factor profile as paramount. This recommendation is in line with the 2010 guidelines for the management of atrial fibrillation produced by the European Society of Cardiology.

How effective is cryoablation for atrial fibrillation during concomitant cardiac surgery?

A best evidence topic in cardiothoracic surgery was written according to a structured protocol. The question addressed was whether performing cryoablative procedures during concomitant cardiac surgical procedures is effective for the treatment of atrial fibrillation (AF). Altogether 291 papers were found using the reported search, of which nine represented the best evidence to answer the clinical question. The authors, journal, date and country of publication, patient group studied, study type, relevant outcomes and results of these papers are tabulated. All studies showed that cryoablation during concomitant surgery had a significant effect on return to sinus rhythm (SR) conversion rate. One study showed that cryoablation was significantly more effective than mitral valve surgery alone at a 12-month follow-up (73.3% vs. 42.9%, respectively, P=0.013). The use of a concomitant cryoablative procedure has also been shown to be far superior to subsequent catheter based cryoablation in returning patients to SR at a 12-month follow-up (82% and 55.2%, respectively, P<0.001). Another study showed a significant return to AF over a three-year period (91.8% and 84.1% at discharge and three years, respectively). Return to SR was significantly decreased in those patients suffering from permanent rather than paroxysmal AF (47% vs. 85%, P<0.001). Paucity of level 1 evidence was a major limitation to this analysis. All nine papers were either small randomised controlled trials or retrospective studies with small sample sizes (57-521) and varied follow-up regimens. Six of nine studies suggested that cryoablation is most successful in patients suffering from paroxysmal rather than permanent AF. A lack of 24-h monitoring in seven of nine studies prevented effective elucidation of the rate of paroxysmal AF following cryoablation. Only one study suggested an increased complication rate from cryoablation, however, none suggested any negative impact on mortality or morbidity. We conclude that cryoablation during concomitant surgery is a safe and acceptable intervention for the treatment of AF with an SR conversion rate of between 60% and 82% at 12-months postsurgery.

Should double lung transplant be performed with or without cardiopulmonary bypass?

A best evidence topic in cardiothoracic surgery was written according to a structured protocol. The question addressed was whether double lung transplantation should be performed with or without cardiopulmonary bypass (CPB) in order to improve postoperative clinical outcomes. Altogether 386 papers were found using the reported search, of which 14 represented the best evidence to answer the clinical question. The authors, journal, date and country of publication, patient group studied, study type, relevant outcomes and results of these papers are tabulated. All 14 papers assessed a range of postoperative outcomes and broadly speaking, six papers found significantly worse outcomes with CPB use, six found no difference and two found a mixture of both depending on the specific outcomes assessed. Dalibon et al. [J Cardiothorac Vasc Anesth 2006;20:668-672] found that mortality was significantly worse in the CPB group at 48 h, one month and one year [P = 0.001, odds ratio (OR) = 246.1; P = 0.083, OR = 2.6; P = 0.001, OR = 5.3, respectively]. Other papers revealed poor outcomes in the CPB group in a range of measures including diffuse alveolar damage (P = 0.009), chest radiograph infiltrate score (P = 0.005), longer intubation time (P = 0.002), longer intensive care unit stay (P = 0.05), and greater incidence of pulmonary reimplantation response (P = 0.03). However, Myles et al. [J Cardiothorac Vasc Anesth 1997;11:177-183] found that only acute postoperative outcomes were significantly worse in their CPB group (P < 0.001); medium- and long-term survival outcomes were not significantly different (P = 0.055). de Boer et al. [Transplantation 2002;73:1621-1627] even found that there was an improved one-year survival rate with CPB use (OR = 0.25, P = 0.038) and that the number of human leukocyte antigen DR (HLA-DR) mismatches influenced this effect. Those papers suggesting no deleterious effects of CPB generally measured similar postoperative outcomes to those mentioned above, with one study also assessing incidence of primary graft failure, which was not significantly different (P = 0.37). We conclude that CPB should continue to be used where clinically indicated for a specific reason (for example, where there is pulmonary hypertension or a requirement for concomitant cardiac repair). However, given that the evidence for using CPB for all elective cases is relatively weak, and the fact that there are strong arguments in the literature for both methods, either approach would be clinically acceptable.

The patients' perspective of carotid endarterectomy

INTRODUCTION

No studies as yet have directly evaluated the patients' perspective of carotid endarterectomy (CEA). Here, we determine patient satisfaction, understanding, and perception of CEA.

METHODS

Consecutive patients were identified from a prospectively maintained carotid database. A validated 10-point telephone questionnaire was conducted. Questions related to preoperative symptoms, experience of procedure, future interventions, and overall patient satisfaction.

RESULTS

Of the 192 patients included, 136 completed the questionnaire (71% response rate). Ninety-two percent were satisfied with the explanation received, however, only 48% understood that CEA aimed to prevent future stroke. Eighty-five percent of patients received local anesthesia (LA) CEA, with 16% reporting severe or unbearable pain. Most patients (83%) would repeat CEA if necessary and 67% stated a future preference for LA CEA. The majority of patients (96%) were satisfied with their treatment overall.

CONCLUSIONS

Most patients were satisfied with CEA. Greater emphasis could be placed on improving preoperative information-giving and intraoperative analgesia.

Should the NHS be privatized? Annual varsity medical debate - London, 22 January 2010

The Varsity Medical Debate, between Oxford and Cambridge Universities, brings together practitioners and the public, professors, pupils and members of the polis, to facilitate discussion about ethics and policy within healthcare. The motion on privatizing the National Health Service (NHS) was specifically chosen to reflect the growing sentiment in the UK where further discourse upon models of healthcare was required. Time and again, the outcome of British elections pivots upon the topic of financial sustainability of the NHS. Having recently celebrated its sixtieth anniversary, the NHS has become heavily politicized in recent months, especially in the aftermath of the devastating global recession.

CREB-dependent Nur77 induction following depolarization in PC12 cells and neurons is modulated by MEF2 transcription factors

Expression of the nuclear orphan receptor gene Nur77 in neuronal cells is induced by activity-dependent increases in intracellular Ca2+ ions. Ca2+ responsiveness of the Nur77 gene has been attributed to two distinct DNA regulatory regions that recruit the transcription factors cAMP response element binding protein (CREB) and myocyte enhancer factor-2 (MEF2). Here we used dominant interfering and constitutively active mutants of CREB and MEF2 proteins to assess their relative contribution to depolarization-induced Nur77 expression in undifferentiated PC12 cells and hippocampal neurons. We show that while CREB is necessary for Ca2+-activated Nur77 expression MEF2 functions to modulate CREB-dependent Nur77 expression by acting as a repressor in quiescent cells.