Mechanical valve replacement for patients with rheumatic heart disease: the reality of INR control in Africa and beyond.

The majority of patients requiring heart valve replacement in low- to middle-income countries (LMICs) need it for rheumatic heart disease (RHD). While the young age of such patients largely prescribes replacement with mechanical prostheses, reliable anticoagulation management is often unattainable under the prevailing socioeconomic circumstances. Cases of patients with clotted valves presenting for emergency surgery as a consequence of poor adherence to anticoagulation control are frequent. The operative mortality rates of reoperations for thrombosed mechanical valves are several times higher than those for tissue valves, and long-term results are also disappointing. Under-anticoagulation prevails in these regions that has clearly been linked to poor international normalised ratio (INR) monitoring. In industrialised countries, safe anticoagulation is defined as >60%-70% of the time in the therapeutic range (TTR). In LMICs, the TTR has been found to be in the range of twenty to forty percent. In this study, we analysed >20,000 INR test results of 552 consecutive patients receiving a mechanical valve for RHD. Only 27% of these test results were in the therapeutic range, with the vast majority (61%) being sub-therapeutic. Interestingly, the post-operative frequency of INR tests of one every 3-4 weeks in year 1 had dropped to less than 1 per year by year 7. LMICs need to use clinical judgement and assess the probability of insufficient INR monitoring prior to uncritically applying Western guidelines predominantly based on chronological age. The process of identification of high-risk subgroups in terms of non-adherence to anticoagulation control should take into account both the adherence history of >50% of patients with RHD who were in chronic atrial fibrillation prior to surgery as well as geographic and socioeconomic circumstances.

Visual mapping of team dynamics and communication patterns on surgical ward rounds: an ethnographic study.

BACKGROUND: The effect of team dynamics on infection management and antimicrobial stewardship (AMS) behaviours is not well understood. Using innovative visual mapping, alongside traditional qualitative methods, we studied how surgical team dynamics and communication patterns influence infection-related decision making. MATERIALS/METHODS: Between May and November 2019, data were gathered through direct observations of ward rounds and face-to-face interviews with ward round participants in three high infection risk surgical specialties at a tertiary hospital in South Africa. Sociograms, a visual mapping method, mapped content and flow of communication and the social links between participants. Data were analysed using a grounded theory approach. RESULTS: Data were gathered from 70 hours of ward round observations, including 1024 individual patient discussions, 60 sociograms and face-to-face interviews with 61 healthcare professionals. AMS and infection-related discussions on ward rounds vary across specialties and are affected by the content and structure of the clinical update provided, consultant leadership styles and competing priorities at the bedside. Registrars and consultants dominate the discussions, limiting the input of other team members with recognised roles in AMS and infection management. Team hierarchies also manifest where staff position themselves, and this influences their contribution to active participation in patient care. Leadership styles affect ward-round dynamics, determining whether nurses and patients are actively engaged in discussions on infection management and antibiotic therapy and whether actions are assigned to identified persons. CONCLUSIONS: The surgical bedside ward round remains a medium of communication between registrars and consultants, with little interaction with the patient or other healthcare professionals. A team-focused and inclusive approach could result in more effective decision making about infection management and AMS.

Investigating infection management and antimicrobial stewardship in surgery: a qualitative study from India and South Africa.

OBJECTIVES: To investigate the drivers for infection management and antimicrobial stewardship (AMS) across high-infection-risk surgical pathways. METHODS: A qualitative study-ethnographic observation of clinical practices, patient case studies, and face-to-face interviews with healthcare professionals (HCPs) and patients-was conducted across cardiovascular and thoracic and gastrointestinal surgical pathways in South Africa (SA) and India. Aided by Nvivo 11 software, data were coded and analysed until saturation was reached. The multiple modes of enquiry enabled cross-validation and triangulation of findings. RESULTS: Between July 2018 and August 2019, data were gathered from 190 hours of non-participant observations (138 India, 72 SA), interviews with HCPs (44 India, 61 SA), patients (six India, eight SA), and case studies (four India, two SA). Across the surgical pathway, multiple barriers impede effective infection management and AMS. The existing implicit roles of HCPs (including nurses and senior surgeons) are overlooked as interventions target junior doctors, bypassing the opportunity for integrating infection-related care across the surgical team. Critically, the ownership of decisions remains with the operating surgeons, and entrenched hierarchies restrict the inclusion of other HCPs in decision-making. The structural foundations to enable staff to change their behaviours and participate in infection-related surgical care are lacking. CONCLUSIONS: Identifying the implicit existing HCP roles in infection management is critical and will facilitate the development of effective and transparent processes across the surgical team for optimized care. Applying a framework approach that includes nurse leadership, empowering pharmacists and engaging surgical leads, is essential for integrated AMS and infection-related care.

Progressive Reinvention or Destination Lost? Half a Century of Cardiovascular Tissue Engineering.

The concept of tissue engineering evolved long before the phrase was forged, driven by the thromboembolic complications associated with the early total artificial heart programs of the 1960s. Yet more than half a century of dedicated research has not fulfilled the promise of successful broad clinical implementation. A historical account outlines reasons for this scientific impasse. For one, there was a disconnect between distinct eras each characterized by different clinical needs and different advocates. Initiated by the pioneers of cardiac surgery attempting to create neointimas on total artificial hearts, tissue engineering became fashionable when vascular surgeons pursued the endothelialisation of vascular grafts in the late 1970s. A decade later, it were cardiac surgeons again who strived to improve the longevity of tissue heart valves, and lastly, cardiologists entered the fray pursuing myocardial regeneration. Each of these disciplines and eras started with immense enthusiasm but were only remotely aware of the preceding efforts. Over the decades, the growing complexity of cellular and molecular biology as well as polymer sciences have led to surgeons gradually being replaced by scientists as the champions of tissue engineering. Together with a widening chasm between clinical purpose, human pathobiology and laboratory-based solutions, clinical implementation increasingly faded away as the singular endpoint of all strategies. Moreover, a loss of insight into the healing of cardiovascular prostheses in humans resulted in the acceptance of misleading animal models compromising the translation from laboratory to clinical reality. This was most evident in vascular graft healing, where the two main impediments to the in-situ generation of functional tissue in humans remained unheeded-the trans-anastomotic outgrowth stoppage of endothelium and the build-up of an impenetrable surface thrombus. To overcome this dead-lock, research focus needs to shift from a biologically possible tissue regeneration response to one that is feasible at the intended site and in the intended host environment of patients. Equipped with an impressive toolbox of modern biomaterials and deep insight into cues for facilitated healing, reconnecting to the "user needs" of patients would bring one of the most exciting concepts of cardiovascular medicine closer to clinical reality.

Rationale and design of a prospective study to assess the effect of left cardiac sympathetic denervation in chronic heart failure.

BACKGROUND: The main causes of mortality in patients with chronic heart failure include sudden cardiac death (SCD) and progressive heart failure. Autonomic dysfunction plays a detrimental role in the progression of chronic heart failure. Left cardiac sympathetic denervation (LCSD) is an inexpensive and safe procedure which modifies autonomic innervation of the heart and is associated with a significant antifibrillatory effect. Whether LCSD reduces the risk of SCD, delays progression of heart failure and improves quality of life in patients with heart failure with reduced ejection fraction (HFrEF) is not known. METHODS AND DESIGN: This is a 2-phased prospective, randomized trial to test the efficacy and safety of LCSD as an adjunct to guideline recommended medical therapy for patients with HFrEF. Once the safety and feasibility of conducting a large LCSD study have been demonstrated in the pilot phase, a phase III efficacy trial to assess the impact on ventricular arrhythmias, heart failure outcomes, and mortality will be completed. Outcome data from the pilot study will remain blinded and added to the results of phase III study for analysis. RESULTS: To date the study has received approval from local and national ethics and regulatory bodies and recruitment has commenced, and 4 patients have been randomized so far. CONCLUSION: If LCSD is proven to be safe, feasible and effective in this first ever study using this novel approach in patients with HFrEF it may be a cost-effective alternative to the implantable cardioverter defibrillator therapy especially in regions where ICDs and cardiac transplantation are unavailable.