Objective: There is wide variations in practice about the exact timing of coronary artery bypass grafting (CABG) post-acute myocardial infarction (AMI) and admission to hospital. This study aims to review current literature evidence to provide an up-to-date evaluation of the optimal CABG timing and parameters indicative of patient outcomes. Method: Electronic literature search was done to look into articles that discussed acute myocardial presentation and their referral for CABG either as urgent in-patient or as elective cases. The evidence was synthesised based on each reported article and their outcomes. Results: The timing of CABG following AMI have been explored in multiple studies, however there is no clear consensus on when to proceed with CABG following AMI and this remains controversial. The mortality rates vary with timing of CABG, but confounding factors such as age, poor pulmonary functions, renal insufficiency, poor left ventricular function and many others can all contribute to the variable reported outcomes. Conclusion: There is need for large, multi-centre study to identify optimal timings for CABG in cases of complex coronary artery diseases or failed PCI in patients with acute MI. Upcoming guidelines should emphasize patient cohorts by taking their risk factors into consideration.
Objective Affecting 1 in 500 individuals; Hypertrophic cardiomyopathy (HCM) is an autosomal dominant cardiovascular disorder which is prevalent throughout the world. Surgical myectomy and alcohol septal ablation (ASA) are two methods currently used for the management of drug refractory Hypertrophic obstructive cardiomyopathy (HOCM). ASA may prove to be a useful, less invasive tool when confronting patients with HOCM especially those who are more elderly or deemed to be a higher surgical risk. Methods Electronic literature search was conducted to identify relevant articles that discussed invasive methods to treat drug refractory HOCM. No limits were placed on timing of the publication or the type of article. Key words and MeSH terms were used to conduct the search and the results were summarized in the relevant section. Results Current evidence suggests that alcohol septal ablation is a safe and effective procedure in treating patients with HOCM with similar short- and long-term outcomes when compared with surgical myectomy. Selection of patient with appropriate assessment is the key for satisfactory outcomes. Conclusion ASA has been shown to be a safe and reliable procedure; advanced imaging techniques and dedicated multi-disciplinary teams can be used to carefully select patients with HOCM. Though surgical myectomy is recommended as gold standard treatment for drug refractory HOCM, however, ASA may play an increasing role in the near future due an ageing population; both ASA and SM can have a synergistic effect in treating those who are affected by HOCM.
Dear Editor,We read with interest the published article by Ikeda et al. , they performed thoracic endovascular aortic repair (TEVAR) in a patient with Marfan syndrome (MFS) for acute complicated type B aortic dissection (TBAD) during COVID-19 pandemic.The evidence around TEVAR for MFS is scarce and open repair remains the gold treatment. During the COVID-19 pandemic, many patients are either being denied treatment or given inferior options on the basis of age, comorbidities and risk of COVID pneumonia; however, the guidelines for aortic intervention in the United Kingdom have remained largely unchanged from pre-COVID-19 era . Our questions to the authors relate to whether their solution was an unnecessary compromise. There is no clear indication defined in their case as a cold leg doesn’t necessary means an ischaemic limb. The TEVAR procedure performed aiming to minimise hospital stay, yet this approach may have put the patient at higher risk of developing paraplegia and visceral organ malperfusion, while compromising her long-term care.There is need to clarify if she had risk factors that prone her to a higher risk acquiring severe COVID-19 which necessitated deviating from the traditional open surgery recommended for MFS patients with TBAD . The authors did not report on renal function, evidence of bowel malperfusion or whether there was resistant hypertension that needed immediate intervention. If the need to expediate intervention was the fear of limb ischaemia, is it conceivable a femoro-femoral bypass could have saved the limb and definitive open surgery on her aorta could have been performed at a later stage, especially since she was haemodynamically stable.Moreover, as Marfan-diseased aortas are prone to further dilatation, we believe their justification for opting for endovascular repair should also have been more balanced, exploring the know high rate of long-term TEVAR-associated complications in MFS patients including endoleaks, retrograde dissection, stent-graft-induced new entry tears, surgical conversions and reintervention. There is also need for imaging follow-up to assess the success of TEVAR and early detection of aforementioned complications.
Under the unprecedented pressures of the global coronavirus disease 2019 (COVID-19) pandemic, there is an urgent requisite for successful strategies to safely deliver cardiac surgery. Severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) was first described in early December 2019, and the rapid spread and emergence of this virus has caused significant disruptions in the delivery of healthcare services worldwide.1,2 In particular, provision of cardiac surgery has been disproportionally affected due to reallocation of intensive care resources, such as ventilators.2Additionally, patients with pre-existing cardiovascular disease are likely to have comorbidities which are associated with poorer clinical outcomes in confirmed SARS-CoV-2 cases.3,4 Despite this, Yandrapalli and colleagues have reported the first case of a successful coronary artery bypass graft (CABG) operation in a patient with asymptomatic SARS-CoV-2 infection, which offers insights into how cardiac surgery could be adapted to solve the challenges of this pandemic.5In response to the burden of COVID-19 on healthcare systems in the United Kingdom (UK), elective cardiac surgeries have been delayed owing to the redistribution of intensive care resources and the unquantifiable risk of acquiring COVID-19.2 Likewise, cardiac surgery services have undergone structural remodelling into a centralised system in an attempt to continue provisions of emergency surgery alongside hospital management of COVID-19 patients.2Unsurprisingly, most cardiac surgery units across the globe have seen a sharp decline in surgeries as a result, and one unit reported an 83% reduction in cardiac index cases between 23rd March to 4th May 2020.2 Similar models have been used in Europe to manage healthcare services and increase intensive care capacity. For example in the Lombardy region of Italy, 16 out of 20 cardiac surgical units discontinued services and all urgent cases have been consequently diverted to the remaining four units for centralised services.6 Whilst these measures have been beneficial for supporting the focused management of COVID-19 patients, it is important to reflect upon the future consequences of delayed elective cardiac surgery. Indeed, such patients are likely to have progressive conditions and further work is needed to investigate the long-term impact of COVID-19 on mortality and morbidity in this cohort.The case report by Yandrapalli and colleagues highlight the importance of routine SARS-CoV-2 testing for all patients requiring cardiac surgery, especially for detecting asymptomatic or subclinical infections.5 Active SARS-CoV-2 infection may precipitate an overproduction of early response proinflammatory cytokines in post-operative period, leading to unfavourable surgical outcomes.7,8 Moreover, preliminary studies have shown that patients with established cardiovascular diseases may have a greater risk of increased SARS-CoV-2 infection severity and prognosis.9 Taken together, assessment for active infection is crucial for risk stratification. In addition, clinicians should consider the threshold for surgery when selecting patients for cardiac surgery. An international, multi-centre cohort study by COVIDSurg Collaborative which included 1128 confirmed SARS-CoV-2 patients undergoing a broad range of surgeries revealed that 30-day mortality risk was significantly associated with the patient demographics of male sex, an age of 70 years or older, and poor preoperative physical health status.10 Collectively, the risks and benefits of cardiac surgery should be carefully considered in such patients due to higher mortality risk.10Alternative therapeutic procedures with rapid discharge, such as percutaneous intervention or medical therapy, may be more appropriate to reduce SARS-CoV-2 related mortality and nosocomial infection risk.11Current evidence is limited for postoperative outcomes in cardiac surgery cases. In the aforementioned cohort study by COVIDSurg Collaborative, the 30-day mortality rate was 23.8%.10In addition, the study reported that 51.2% of patients had postoperative pulmonary complications, which was associated with a higher mortality rate of 38.0%.10 In another case report describing an emergency CABG operation, the asymptomatic patient succumbed to pulmonary complications arising from a SARS-CoV-2 infection confirmed postoperatively.12 The authors acknowledge that the undiagnosed infection may have triggered a refractory pathological response after cardiac surgery. Indeed, recent literature has suggested that patients with SARS-CoV-2 are at higher risk of developing thromboembolisms, possibly mediated by the interaction with angiotensin-converting enzyme 2 (ACE2) receptors.13Similarly, there is a consensus that SARS-CoV-2 has direct adverse effects on the myocardium due to high expression of ACE2.14 As such, SARS-CoV-2 can potentially trigger multisystem complications which require vigilant monitoring, especially in patients requiring cardiopulmonary bypass and at high risk of developing thromboembolisms. Cardiac surgery patients represent a vulnerable patient population, and this cohort may experience worse outcomes with SARS-CoV-2 infection based on the current available evidence. In the latest recommendation, UK currently advises all patients who are listed for elective cardiac surgery to self-isolate for 14 days prior to surgery date, in a measure to limit and contain the exposure of such cohort to the smallest possibilities of acquiring COVID-19.Currently, the future of cardiac surgery after the pandemic is unclear as the evidence is still emerging. However, the lessons learnt from these unprecedented times can be taken forward to inform future service planning. Moving forwards, routine screening of patients for SARS-CoV-2 infection will undoubtedly play a key role in identifying asymptomatic or subclinical infections. The preoperative UK National Health Service testing recommendations should be broadened so that all patients undergoing cardiac surgery are screened, given the higher risk of postoperative complications in this population. Similarly, repeat testing is important for monitoring patients for concomitant infections. Alongside changes to hospital protocol, service delivery will inevitably shift. The successful application of telemedicine during the pandemic has already been reported in the delivery of oncology services.15 Moreover, the benefits of telecardiology outside of the COVID-19 era have been previously reported, and cardiology services will likely embrace the utilisation of telemedicine for managing outpatient consultations.16 Units will also have to address the vast backlog of surgeries caused by cancellation of elective cardiac operations in a sustainable manner, with adequate hospital space and personal protective equipment availability.17 In order to resume success services, planning for this eventuality should begin now and patients at significant mortality risk due to delayed surgery need to be prioritised.Ultimately, clear guidelines should be implemented to ensure safe resumption of surgical services, whilst also reassuring patients concerned about safety.3 Whilst the future trajectory of this pandemic is uncertain, the insights from the impact of COVID-19 on cardiac surgery will undoubtedly shape the future delivery of cardiac surgery.
Extra Corporeal Membrane Oxygenation (ECMO) is a supportive therapy used to provide cardiac support with or without respiratory support in the event of cardiopulmonary failure. The two main types of ECMO are Veno-arterial ECMO (VA-ECMO) and Veno-venous ECMO (VV-ECMO). The use of ECMO in cardiac surgery has been established in cases of post-cardiotomy cardiogenic shock which is refractory to conventional therapy with inotropes and intra-aortic balloon pulsation support. Survival for this, otherwise, fatal condition has been shown to be improving through the use of ECMO. However, the decision and timing to initiate ECMO therapy remains selective and is dependent on a range of factors such as patient factor, clinician’s judgement, meaning there is no consistent and solid ground regarding the timing of ECMO initiation. This article will provide an extensive review of ECMO indications, contraindications, complications and outcomes to analyse the survival benefit of ECMO following cardiac surgery.
For patients undergoing cardiopulmonary bypass, myocardial protection is a key for successful recovery and improved outcomes following cardiac surgery that requires cardiac arrest. Different solutions, components, and modes of delivery have evolved over the last few decades to optimise myocardial protection. These include; cold and warm, blood and crystalloid solution through antegrade, retrograde or combined cardioplegia delivery approach. However, each method has its own advantages and disadvantages, posing a challenge to establish a gold standard cardioplegic solution with an optimised mode of delivery for enhanced myocardial protection during cardiac surgery. The aim of this review is to provide a brief history of the development of cardioplegia, explain the electrophysiological concepts behind myocardial protection in cardioplegia, analyse the current literature and summarise existing evidence that warrants the use of varying cardioplegic techniques. We provide a comprehensive and comparative overview of the effectiveness of each technique in achieving optimal cardioprotection and propose novel techniques for optimising myocardial protection in the future.
There remains a significant paucity of information evaluating the effect of glycated HbA1c levels and its theorized effect on mortality and morbidity rates following cardiac surgery. Diabetes is a very common comorbidity in patients undergoing open heart surgery as there is shift in patient characteristics and being higher risk. Currently, the evidences are controversial and there is no clear consensus that increased HbA1c levels is associated with an increased perioperative mortality rate. However, reported literature are more commonly able to demonstrate elevated HbA1c levels to be associated with increased rates of wound infection, cardiovascular events and renal failure; thus, higher morbidities postoperatively. This literature review aims to examine the evidence synthesis behind each of morbidities and mortalities associated with open heart surgery and the impact of high HbA1c on the reported outcomes.