Management of acute aortic dissection in critical care.

Aortic dissections are associated with significant mortality and morbidity, with rapid treatment paramount. They are caused by a tear in the intimal lining of the aorta that extends into the media of the wall. Blood flow through this tear leads to the formation of a false passage bordered by the inner and outer layers of the media. Their diagnosis is challenging, with most deaths caused by aortic dissection diagnosed at post-mortem. Aortic dissections are classified by location and chronicity, with management strategies depending on the nature of the dissection. The Stanford method splits aortic dissections into type A and B, with type A dissections involving the ascending aorta. De Bakey classifies dissections into I, II or III depending on their origin and involvement and degree of extension. The key to diagnosis is early suspicion, appropriate imaging and rapid initiation of treatment. Treatment focuses on initial resuscitation, transfer (if possible and required) to a suitable specialist centre, strict blood pressure and heart rate control and potentially surgical intervention depending on the type and complexity of the dissection. Effective post-operative care is extremely important, with awareness of potential post-operative complications and a multi-disciplinary rehabilitation approach required. In this review article we will discuss the aetiology and classifications of aortic dissection, their diagnosis and treatment principles relevant to critical care. Critical care clinicians play a key part in all these steps, from diagnosis through to post-operative care, and thus a thorough understanding is vital.

Aortic arch replacement with simultaneous antegrade cerebral and systemic perfusion using a single centrifugal pump driven 'split arterial line' extracorporeal circuit design.

The ability to provide antegrade cerebral and systemic perfusion simultaneously may negate the requirement for any prolonged period of circulatory arrest during complex aortic arch reconstruction procedures, depending on the cannulation strategy. We describe the development and successful implementation of a custom 'split arterial line' extracorporeal circuit configuration to facilitate complex aortic surgery. This circuit design offers a wide range of cannulation and perfusion strategies, is safe, adaptable, simple to manage, and avoids the use of roller pumps for blood delivery, which are associated with deleterious haematological complications during prolonged cardiopulmonary bypass cases. The split arterial line approach has now become the standardised methodology for facilitating complex aortic surgery at our institution.

Surgical Complexity and Outcome of Patients Undergoing Re-do Aortic Valve Surgery.

Objectives: Re-do aortic valve surgery carries a higher mortality and morbidity compared with first time aortic valve replacement (AVR) and often requires concomitant complex procedures. Transcatheter aortic valve replacement (TAVR) is an option for selective patients. The aim of this study is to present our experience with re-do aortic valve procedures and give an insight into the characteristics of these patients and their outcomes. Methods: Retrospective review of 80 consecutive re-do aortic valve procedures. Results: Mean patients' age was 51.80±18.73 years. Aortic regurgitation (AR) was present in 51 (65.4%) patients and aortic stenosis (AS) in 38 (48.7%). Indications for reoperation were: infective endocarditis (IE) (23.8%), bioprosthetic degeneration (12.5%), mechanical valve dysfunction (5%), paravalvular leak (6.2%), patient-prosthesis mismatch (3.8%), native valve disease (25%), aortic aneurysm, pseudoaneurysm and dissection (35%), aortic root/homograft degeneration (27.5%). Forty-one (51.2%) patients underwent re-do AVR, 39 (48.8%) re-do complex aortic valve surgery (28 root, 23 ascending aorta and 6 hemiarch procedures) and 37.5% concomitant procedures. A bioprosthesis was implanted in 43.8%, a mechanical valve in 37.5%, a composite graft in 2.5%, a Biovalsalva graft in 6.2% and a homograft in 10% of patients. In-hospital mortality was 3.8% and incidence of major complications was low. Conclusions: A significant proportion of patients were young (61%<60 y), required complex aortic procedures (49%) or presented with contraindications for TAVR (mechanical valve, AR, IE, proximal aortic disease, need for concomitant surgery). Re-do aortic surgery remains the only treatment for such challenging cases and can be performed with acceptable mortality and morbidity in a specialised aortic centre.

Successful treatment of ischaemic VSD and acute RV failure: a challenging case in the modern NHS.

A 52-year-old man, previously fit and well, presented with myocardial infarction complicated by ischaemic ventricular septal defect (VSD) and acute right ventricular failure, was successfully treated with early percutaneous coronary reperfusion, surgical VSD repair and temporary right ventricular assist device (VAD) support. This case is an example of how a modern healthcare system can successfully manage complex emergency cases, combining high levels of clinical care and medical technology. Access to temporary mechanical support played a vital role in this case. We believe that wider access to VADs may contribute to improvement in the, widely recognised, poor outcome of ischaemic VSD.

Aortic valve repair techniques: an early UK experience.

Objectives: Retrospective review of early results with aortic valve repair (AVr) techniques. Methods: 61 consecutive patients underwent AVr surgery at our institutions between 2008 and 2018. 14 patients had a bicuspid aortic valve and 16 had a connective tissue disorder. In 48 patients, aortic regurgitation (AR) was secondary to an aortic root and/or ascending aneurysms, while in 13 it was due to primary cusp pathologies. 13 patients underwent isolated cusp repair, 19 sinotubular junction remodelling, 25 valve-sparing root replacement (VSRR) and 4 hemiroot replacement. Cusp repair techniques included: 18 free margin plication, 18 commissural re-suspensions, 3 raphe resections and 1 free-edge reinforcement. Subcommissural annuloplasty was performed in 25 patients (42%) with a dilated annulus (>28 mm). Results: 50 patients (82%) left the operating theatre with no AR, 8 with mild central and 3 with mild eccentric AR. In-hospital survival was 100%. Clinical follow-up was complete at 5.08±2.29 years and all patients were alive. Transthoracic echocardiographic follow-up was complete at 2.35±1.92 years and showed the presence of a moderate AR in 10 patients (18%) and severe AR in 2 patients (4%). One of these required re-do aortic valve replacement 6 years after VSRR. Freedom from re-operation at 8 years was 88.15%±1.51%. Conclusion: Good early results are achievable following AVr with acceptable medium-term outcomes. AVr surgery continues to evolve, and concentrating the experience in specialist centres in the UK is recommended.

Surgical management of adrenal tumours extending into the right atrium.

This paper discusses the surgical approach for the treatment of adrenal tumours extending into the right atrium (RA), using a cardio-pulmonary bypass (CPB) associated with deep hypothermic circulatory arrest (DHCA). Pre-operative planning and surgical steps are described in details. The association of CPB with hypothermic circulatory arrest (HCA) provides a bloodless operating field, direct intra-vascular vision, reduces the risk of embolization and allows extensive inferior vena cava (IVC) or RA repair in cases of infiltration of the vascular wall. Establishing a dedicated multidisciplinary team with experience in managing these challenging cases is fundamental to offer treatment to patients with advanced disease, who would otherwise risk being turned down for surgery. A close collaboration between general and cardiac surgeons and a deep understanding of the surgical procedure steps are fundamental to safely performing these procedures. We advocate centralising adrenal surgery in a small number of units with adequate multidisciplinary support.

Conversion to sinus rhythm by ablation improves quality of life in patients submitted to mitral valve surgery.

BACKGROUND: Atrial fibrillation can be successfully treated with surgical ablation, but the effect of restoring sinus rhythm on the quality of life has yet to be established. We evaluate the effects of left atrial ablation combined with mitral valve surgery on health-related quality of life in patients with permanent atrial fibrillation. METHODS: Ninety-one consecutive patients with permanent atrial fibrillation underwent mitral valve surgery at our division. The last 53 also received left atrial ablation by means of monopolar radiofrequency and excision of the left appendage. The patients were divided into two groups according to the median total score obtained at the Short Form 36 Health Survey used to evaluate their quality of life (ie, the good quality of life group [n = 54] and the poor quality of life group [n = 37]). RESULTS: Preoperative and intraoperative data of the two groups were similar. In-hospital mortality and morbidity were similar in both groups. Sinus rhythm was obtained in 68% of patients (36 of 53) treated with left atrial ablation and it occurred spontaneously in 10% of patients (4 of 38) treated for the mitral pathology only. At follow-up, there was no difference between the groups in ejection fraction, left atrial diameter, mitral dysfunction, tricuspidal regurgitation, and New York Heart Association functional class. Using stepwise logistic regression, only the presence of sinus rhythm was associated with better quality of life. CONCLUSIONS: In patients submitted to mitral surgery, conversion to sinus rhythm by left atrial ablation can significantly improve the health-related quality of life.