CARDIOVASCULAR JOURNAL OF AFRICA • Volume 34, No 2, May/June 2023 126 AFRICA Complications of LVADs include bleeding, pump thrombosis, stroke and right heart failure. Bleeding is a common adverse event in the early (< 90 days) postoperative period following LVAD implantation and is a frequent complication in the late period (≥ 90 days), with nearly one-third of patients experiencing a major bleeding episode by one year.47 Late bleeding is most commonly due to gastrointestinal bleeding, which accounts for nearly 60% of all LVAD-associated bleeding. Antiplatelet and anticoagulation therapies, an acquired Von Willebrand syndrome and the development of angiodysplasias are believed to be contributory to gastrointestinal bleeding in LVAD patients. Cessation of antiplatelet and/or anticoagulation therapy as well as reversal with vitamin K, fresh frozen plasma, or prothrombin complex concentrate is useful. Procedurally based strategies during an acute bleed include cauterisation, arterial embolisation, and, in extreme cases, surgical intervention. LVAD thrombotic events have decreased over the past few years due to innovations in LVAD pump design, especially with the HM3. The incidence of suspected or confirmed LVAD thrombosis at two years was significantly lower with the HM3 than the HMII device, occurring in seven (1.4%) versus 70 patients (13.9%) (p < 0.001).48 Treatment for suspected LVAD thrombosis includes increased antithrombotic and antiplatelet therapies and early LVAD exchange, LVAD explanation (in case of significant myocardial recovery), or consideration of urgent HT. External driveline exit-site abdominal wall infections represent the majority of LVAD infections. Excellent driveline hygiene is important for infection prevention. Infections with cellulitis and drainage may be managed with oral antibiotics but intravenous antibiotics and surgical debridement may also be used. In extreme cases, complete pump exchange or explant and even HT may be needed. Haemorrhagic and ischaemic stroke remain a significant source of morbidity associated with LVADs because of their catastrophic effect on functional capacity and quality of life. In many cases it makes patients ineligible for HT. Ischaemic and haemorrhagic strokes occur after LVAD implantation, with an incidence ranging from five to 30%, varying by device type.49-52 Risk factors for stroke vary by device type and include age, presence of infections, antiplatelet and anticoagulant therapies, and elevated blood pressure.48,53-55 Haemorrhagic strokes are thought to be related to hypertension with anticoagulation, highvelocity intracranial flow, and/or haemorrhagic conversion from prior thromboembolic stroke. Right heart failure (RHF) is a source of morbidity and mortality in patients in the early (< 30 days) and late (> 30 days) period following LVAD placement.56 Late RHF has been associated with higher risk of hospitalisation, gastrointestinal bleed, stroke, infection and worse quality of life.56 Therapies for this condition are limited and include high doses of diuretics, continuous inotrope infusions and HT in eligible patients.56,57 HT: updates and general care of the HT patient HT remains the gold-standard treatment for end-stage (D) HF with more than 6 000 heart transplants performed annually worldwide, with one-year post-transplant survival > 90%.58 Although the first HT in the world was performed by Dr Christian Bernard in South Africa in 1967 and the patient died of rejection a few days later, HT is rarely performed in SSA, with the majority being done in North America and Western Europe.58,59 The average life expectancy is 13 years but many patients live over 20 years, and some patients live for more than 30 years. Limited intensive care capacity, lack of surgical expertise, and lax or non-existent organ donation laws are postulated reasons why HT is unlikely to be performed in Nigeria or SSA. However, emphasising heart disease prevention with evidence-based medications and lifestyle changes may be a more cost-effective measure. Short-term complications include allograft rejection and infections. Immunosuppressants (calcineurin inhibitors, antimetabolites and steroids) are commonly used to suppress the immune system to prevent cardiac allograft rejection. HT recipients are also prone to infection because of immunosuppressants. Cardiac allograft rejection can be acute cellular rejection (and the risk of occurrence is highest in the first year post transplant) or antibody-mediated rejection. It is treated with high-dose steroids, plasmapheresis, intravenous immunoglobulin ± rituximab. Surveillance of allograft rejection has traditionally involved endomyocardial biopsies although the role of non-invasive graft surveillance using donor-derived cellfree DNA is now emerging.60 Infections usually occur within the first six months post transplant and can be common communityacquired infections. Long-term complications of HT include cardiac allograft vasculopathy, hypertension, renal dysfunction, diabetes mellitus, malignancies, infections, and medication side effects. Cardiac allograft vasculopathy is a late complication of HT characterised by a unique form of accelerated coronary disease affecting both intramural and epicardial coronary arteries and veins. It is a common cause of re-transplantation. Hypertension post HT is multifactorial and due to steroids, which can accelerate underlying atherosclerotic disease, calcineurin inhibitors and renal dysfunction. Malignancies, usually skin malignancies and post-transplant lymphoproliferative disorder, are common. Future directions Future directions include the need for enhanced collaboration between the cardiologists in Nigeria and the diaspora to ensure diffusion of best practices and identification of areas of unmet need as targets for future conferences. These include: • Bolstering capacity of the cardiology workforce through cardiovascular competency training for cardiology trainees and improving intensive care unit availability and cardiac catheterisation laboratory services. These are still major challenges, despite the rising burden of ischaemic cardiomyopathy. • Improving access to medications through ‘fair pricing’ to ensure that medications are obtained at ‘discontinued’ cost and increasing the role of health insurance programmes for HF to prevent catastrophic out-of-pocket medical expenditures.61 Accumulating evidence regarding the efficacy of the polypill may diminish the pill burden, which has the potential to assist adherence to GDMT.62,63 • Implementing strategies to improve enrollment of African patients in contemporary HF clinical trials to advance diversity of trial participants and ensure that medications are available to the populations that they will eventually be marketed to.
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