CARDIOVASCULAR JOURNAL OF AFRICA • Volume 35, No 1, January – April 2024 AFRICA 23 (in avoidance of anticoagulation), or in patients who cannot withstand open-heart surgery, such as those with significant co-morbidities, frail elderly, irreversible pulmonary hypertension and severe left ventricular systolic dysfunction.8,11 Apart from the risk imposed by warfarin on pregnancy, managing a patient with a mechanical heart valve in resource-constrained countries is challenging in terms of anticoagulants and monitoring of the INR.52,53 Other advantages are those related to its lower cost, lower morbidity rate, and lower procedure-related mortality rate.6,19,21,22,54 In the current study, among the 12 patients who underwent PBMV, five (41.7%) had a Wilkins score ≤ 8 and seven (58.3%) had a score of 9–11. There was a procedural technical failure in two patients, both of whom had a score of 8. This implies that the success of PBMV is not solely dependent on the score. In one patient there was a failure to cross a severely stenosed valve, and failure of septal puncture in the second. Similarly, previous studies have reported the failure rate ranging from one to 17%.55 The often-reported causes of failure are the inability of atrial septal puncture or to correctly position the balloon across the valve.55 Unfavourable anatomy such as predominant subvalvular stenosis or severe valve stenosis can also result in failures.55 Usually, the commonest reason for failure to cross the valve is when the septal puncture is either too posterior or too anterior. In our cohort, these procedures were done under the supervision of experienced operators and TEE guidance, and therefore the techniques were correct. In a patient in whom we failed to puncture the septum despite correct positioning of a sharp Brockenbrough needle at the fossa ovalis, we speculate that could have been due to the extended rheumatic/inflammatory process involving the septum. In the second patient in whom we failed to cross the mitral valve orifice despite attempting several manoeuvres, the huge left atrium could have been the reason. Intracardiac echocardiography (ICE) is nowadays considered the imaging modality of choice to guide puncture of the septum, however, the device is expensive, hence limiting its application in most settings.55 Recent studies suggest improved visualisation of the septum and assessing of tenting during puncture of the septum by use of the real-time 3D TEE.55 One of the failed PBMV in our cohort was converted to mitral valve surgery and the other one was on the waiting list for the same. Ten patients who underwent a successful PBMV were on a regular clinical follow up. Our findings are important to Africa as a whole because Tanzania, being the host of the East African Centre of Excellence for Cardiovascular Sciences (EACoECVS), identified RHD as a priority disease due to its high morbidity and mortality rates in Africa.2,56,57 Therefore, the lessons learnt will be useful to the East African community and the rest of Africa. The strategies of involving the heart team in selecting patients and eventual steps resulted in good short outcomes among patients who underwent PBMV. Our collaboration with the USA, which was implemented in Uganda a few years ago, albeit a different approach, proved to be effective.58 Similarly, several approaches to enhance PBMV skills in Africa have been suggested, for instance, using 3D and 4D echocardiography.47 This is because 3D echocardiography has been shown to assess the mitral valve anatomy with accuracy, and guide atrial septal puncture, giving a clinician a better view to provide good PBMV outcomes.55,59,60 However, the high cost of balloons in resource-limited countries and the setting where many patients do not have health insurance needs consideration. In this study, half of the patients had a monthly income of less than 42$. Activity such as a recent PBMV workshop alongside the Tokyo International Conference on African Development (TICAD 8) in Tunisia, whereby one young cardiologist per African country was supported to attend, is an example of a forum to discuss challenges related to PBMV in Africa.61 In our study, there was a female predominance (74.4%). Similarly, other previous RHD studies62–70 have shown that the disease is more common in females than males. The reasons for these differences are not known.65,71,72 Intrinsic factors such as genetically mediated immunological factors that predispose women to autoimmune disease have been implicated.73 Extrinsic factors, such as child-rearing, which might result in repeated exposure to group A streptococcus and limited access to healthcare, where males are given more priority than females when they fall ill, also have been implicated.71,72 Recently, prothymosin-alpha has been associated with a potential mediator of gender predisposition in RHD.74 In the current study, two female patients aged 11 and 13 years presented with symptomatic rheumatic MS at six and eight years, respectively. Similarly, other studies report that MS in Africa shows a female predominance with presentation in early life.3,4 These findings underscore a need for screening (as a cost-effective measure) for sub-clinical RHD among the at-risk population, as recommended by the World Heart Organisation (WHO), as an effective way to detect the disease at an early stage when secondary prophylaxis can be administered.75 A recent publication of a clinical trial fromUganda confirmed the prevention of progression of sub-clinical RHD disease among children given secondary prophylaxis.76 In the current study, four (9.3%) patients were first diagnosed with RHD during pregnancy. They all had uneventful spontaneous vertex deliveries before intervention. Similarly, other African studies have shown that it is not uncommon to discover patients with RHD during pregnancy and delivery, most presenting with heart-failure symptoms.42,77 In Africa, RHD in pregnancy is increasingly being detected, accounting for up to 30% of heart diseases in pregnancy and it is associated with poor outcomes for the mother and baby.42,78,79 The 2018ESCguidelines on themanagement of cardiovascular diseases during pregnancy recommend performing risk assessment in all women of childbearing age with cardiac diseases using the modified WHO classification (class I–IV) of maternal risk.80 Pregnancy is contra-indicated in patients who fall into class IV. Another important observation from this study is that most of the patients recruited in the TAMS study came from the northern zone of the country. Similarly, anecdotal data shows that RHD is prevalent in the northern part of Tanzania. However, this observation needs proper investigation in disease mapping as it could be a potential source of information for use in preventative measures. Strengths and limitations The study has several advantages. First, being a prospective study, there was a potential for follow up of these patients. Second, it provides baseline data for future comparisons. Third,
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