The causes, treatment, and outcome of pulmonary hypertension in Africa: Insights from the Pan African Pulmonary Hypertension Cohort (PAPUCO) Registry

Spectrum of Heart Diseases in Children in a National Cardiac Referral Center Tanzania, Eastern Africa: A Six-Year Overview

Background

While communicable diseases have long been the primary focus of healthcare in Africa, the rising impact of paediatric and congenital heart disease (CHD) cannot be overlooked. This research aimed to estimate the frequency and pattern of heart diseases in children who underwent their first echocardiography at a national cardiac referral hospital in Tanzania.

Methods

A retrospective observational study was conducted on children aged 0 to 18 years referred for first-time cardiological evaluation from January 2017 to December 2022. Retrieval of social and echocardiogram data and descriptive analysis were performed.

Results

There were 6,058 children with complete reports. Of these, 52.8% (3,198) had heart disease, of whom 2,559 (80%) had CHD, while (340/639; 53.2%) with acquired heart disease (AHD) had rheumatic heart disease (RHD). Children with CHD had a median age 1.0 years (IQR: 0.3-3.5) and were predominantly 51.2% male. Children with RHD had a median age 9.7 years (IQR: 3.2-13.8) with equal gender distribution. Shunt lesions were common in 1,487 (58.1%), mainly VSD 19.3%, PDA 19.1%, ASD 15.1%, and atrioventricular septal defect (AVSD) 4.6%. Pulmonary valve stenosis was in 97 (3.8%). Around 35% (718) had cyanotic CHD, with TOF being most common (13.3%), followed by double outlet right ventricle (DORV) (3.6%). Compared to global average truncus arteriosus was higher in 69 (2.3%) children. In contrast, TGA and hypoplastic left heart syndrome (HLHS) were lower than the estimated global average seen in 2.3% and 0.5% of the cases, respectively. Atresia of the right-side valves was more common (174 vs. 24), and approximately 40% of the patients referred for first-time echocardiographic evaluation required hospitalization.

Conclusion

Congenital heart disease is the primary cause of heart disease in children presenting at a national referral hospital, surpassing RHD. With its distinct distribution pattern, acyanotic lesions are more frequent than cyanotic heart diseases. The observed late referral tendencies suggest improving the referral system, enhancing CHD awareness among healthcare professionals, and instituting nationwide screening programs.

Hypertension among people living with human immunodeficiency virus in sub-Saharan Africa: a systematic review and meta-analysis

We performed a systematic review and meta-analysis of hypertension in people living with human immunodeficiency virus (HIV) in sub-Saharan Africa (SSA). We searched the PubMed, Google Scholar, African Index Medicus, and Embase databases to identify studies published from January 1, 2010, to December 31, 2021. We used a random-effects model to estimate the pooled prevalence of hypertension and mean SBP/DBP level on a sex-specific basis. We included 48 studies reporting data on a pooled sample of 193,843 people living with HIV (PLW-HIV) in SSA. The pooled mean SBP/DBP level was 120 (95% CI 113-128)/77 (95%CI 72-82) mmHg, while the overall pooled prevalence of hypertension was 21.9% (95% CI 19.9-23.9%). Further meta-regression analyses suggested that the prevalence of hypertension was 1.33 times greater in males, 1.23 times greater in individuals receiving antiretroviral therapy (ART) and 1.45 times greater in those individuals with a CD4-count ≥ 200. This meta-analysis of the contemporary pattern of BP levels among PLW-HIV in SSA, suggests that around one in five of such individuals also have hypertension. Given the further context of greater access to ART and subsequently greater longevity, study findings support calls to integrate cardiovascular management into routine HIV care.

Pulmonary hypertension and the potential of 'drug' repurposing: A case for African medicinal plants

Abstract

Pulmonary hypertension (PH) is a haemodynamic disorder in which elevated blood pressure in the pulmonary circulation is caused by abnormal vascular tone. Despite advances in treatment, PH mortality remains high, and drug repurposing has been proposed as a mitigating approach. This article reviews the studies that have investigated drug repurposing as a viable option for PH. We provide an overview of PH and highlight pharmaceutical drugs with repurposing potential, based on limited evidence of their mechanisms of action. Moreover, studies have demonstrated the benefits of medicinal plants in PH, most of which are of Indian or Asian origin. Africa is a rich source of many medicinal plants that have been scientifically proven to counteract myriad pathologies. When perusing these studies, one will notice that some African medicinal plants can counteract the molecular pathways (e.g. proliferation, vasoconstriction, inflammation, oxidative stress and mitochondrial dysfunction) that are also involved in the pathogenesis of PH. We review the actions of these plants with actions applicable to PH and highlight that they could be repurposed as adjunct PH therapies. However, these plants have either never been tested in PH, or there is little evidence of their actions against PH. We therefore encourage caution, as more research is needed to study these plants further in experimental models of PH while acknowledging that the outcomes of such proof of-concept studies may not always yield promising findings. Regardless, this article aims to stimulate future research that could make timely contributions to the field.

Study synopsis

What the study adds. Pulmonary hypertension (PH) remains a fatal disease, and 80% of the patients live in developing countries where resources are scarce and specialised therapies are often unavailable. Drug repurposing is a viable option to try to improve treatment outcomes.Implications of the findings. We propose that another form of 'drug' repurposing is the use of medicinal plants, many of which have demonstrated benefits against pathological processes that are also key in PH, e.g. apoptosis, tumour-like growth of cells, proliferation, oxidative stress and mitochondrial dysfunction.

Perspectives from the 2nd International Post-Tuberculosis Symposium: mobilising advocacy and research for improved outcomes

In 2020, it was estimated that there were 155 million survivors of TB alive, all at risk of possible post TB disability. The 2nd International Post-Tuberculosis Symposium (Stellenbosch, South Africa) was held to increase global awareness and empower TB-affected communities to play an active role in driving the agenda. We aimed to update knowledge on post-TB life and illness, identify research priorities, build research collaborations and highlight the need to embed lung health outcomes in clinical TB trials and programmatic TB care services. The symposium was a multidisciplinary meeting that included clinicians, researchers, TB survivors, funders and policy makers. Ten academic working groups set their own goals and covered the following thematic areas: 1) patient engagement and perspectives; 2) epidemiology and modelling; 3) pathogenesis of post-TB sequelae; 4) post-TB lung disease; 5) cardiovascular and pulmonary vascular complications; 6) neuromuscular & skeletal complications; 7) paediatric complications; 8) economic-social and psychological (ESP) consequences; 9) prevention, treatment and management; 10) advocacy, policy and stakeholder engagement. The working groups provided important updates for their respective fields, highlighted research priorities, and made progress towards the standardisation and alignment of post-TB outcomes and definitions.

Diagnosis and Treatment Patterns of Chronic Thromboembolic Pulmonary Hypertension in Russia, Kazakhstan, Turkey, Lebanon, and Saudi Arabia: A Registry Study

BACKGROUND

Patients with chronic thromboembolic pulmonary hypertension (CTEPH) in countries with limited resources have, to date, been poorly represented in registries.

OBJECTIVE

This work assesses the epidemiology, diagnosis, hemodynamic and functional parameters, and treatment of CTEPH in Russia, Kazakhstan, Turkey, Lebanon, and Saudi Arabia.

METHODS

A prospective, cohort, phase IV, observational registry with 3-year follow-up (n = 212) in patients aged ≥ 18 years diagnosed with CTEPH was created. Clinical, hemodynamic, and functional parameters were obtained at an initial visit, follow-up visits, and a final visit at the end of 3 years' observation or end of follow-up. Data were recorded on electronic case report forms. Parameters evaluated included 6-minute walking distance (6MWD), use of pulmonary endarterectomy (PEA), balloon pulmonary angioplasty (BPA), pulmonary hypertension (PH)-targeted therapy, and survival. All statistical analyses were exploratory and descriptive, and were performed in the overall population.

RESULTS

The most common symptoms were typical of those expected for CTEPH. Almost 90% of patients underwent right heart catheterization at diagnosis or initial study visit. In total, 66 patients (31%) underwent PEA before the initial visit; 95 patients (45%) were considered operable, 115 (54%) were inoperable, and two (1%) had no operability data. Only 26 patients (12%) had been assessed for BPA at their initial visit. PH-targeted therapy was documented at diagnosis for 77 patients (36%), most commonly a phosphodiesterase type 5 inhibitor (23%). Use of PH-targeted therapy increased to 142 patients (67%) at the initial visit, remaining similar after 3 years. Use of riociguat increased from 6% of patients at diagnosis to 38% at 3 years. Between baseline and end of observation, results for patients with paired data showed an increase in 6MWD. Survival at the end of observation was 88%.

CONCLUSIONS

These data highlight the current diagnosis and management of CTEPH in the participating countries. They show that early CTEPH diagnosis remains challenging, and use of off-label PH-targeted therapy is common.

CLINICALTRIALS

gov: NCT02637050; registered December 2015.

The prevalence of pulmonary hypertension in post-tuberculosis and active tuberculosis populations: a systematic review and meta-analysis

BACKGROUND

The prevalence of tuberculosis (TB)-associated pulmonary hypertension (PH) has not previously been quantified, resulting in an underappreciated burden of disease. We aimed to estimate the prevalence of PH in post-TB and active TB populations.

METHODS

In this systematic review and meta-analysis, we searched PubMed/Medline, Cochrane Library, EBSCOhost, Scopus, African Journals Online and Google Scholar, with no language restriction, for available literature published after 1950. Eligible studies described adult participants (≥16 years), with documented evidence of active or prior TB, diagnosed with PH. Study quality was assessed using a risk of bias tool specifically developed for prevalence studies. Aggregate prevalence estimates with 95% confidence intervals were synthesised using a random-effects meta-analysis model, incorporating the Freeman-Tukey transformation. Subgroup analysis was conducted to ascertain prevalence estimates in specific patient populations.

RESULTS

We identified 1452 unique records, of which 34 met our inclusion criteria. 23 studies, with an acceptable risk of bias and where PH was diagnosed at right heart catheterisation or echocardiography, were included in the meta-analysis. In post-TB studies (14/23), the prevalence of PH was 67.0% (95% CI 50.8-81.4) in patients with chronic respiratory failure, 42.4% (95% CI 31.3-54.0) in hospitalised or symptomatic patients and 6.3% (95% CI 2.3-11.8) in nonhealthcare-seeking outpatients (I2=96%). There was a lower estimated prevalence of PH in studies of populations with active TB (9.4%, 95% CI 6.3-13.0), I2=84%).

CONCLUSION

Our results highlight the significant burden of PH in post-TB and active TB populations. We emphasise the need for increased recognition of TB-associated PH and additional high-quality prevalence data.

Pulmonary hypertension

Pulmonary hypertension encompasses a range of conditions directly or indirectly leading to elevated pressures within the pulmonary arteries. Five main groups of pulmonary hypertension are recognized, all defined by a mean pulmonary artery pressure of >20 mmHg: pulmonary arterial hypertension (rare), pulmonary hypertension associated with left-sided heart disease (very common), pulmonary hypertension associated with lung disease (common), pulmonary hypertension associated with pulmonary artery obstructions, usually related to thromboembolic disease (rare), and pulmonary hypertension with unclear and/or multifactorial mechanisms (rare). At least 1% of the world's population is affected, with a greater burden more likely in low-income and middle-income countries. Across all its forms, pulmonary hypertension is associated with adverse vascular remodelling with obstruction, stiffening and vasoconstriction of the pulmonary vasculature. Without proactive management this leads to hypertrophy and ultimately failure of the right ventricle, the main cause of death. In older individuals, dyspnoea is the most common symptom. Stepwise investigation precedes definitive diagnosis with right heart catheterization. Medical and surgical treatments are approved for pulmonary arterial hypertension and chronic thromboembolic pulmonary hypertension. There are emerging treatments for other forms of pulmonary hypertension; but current therapy primarily targets the underlying cause. There are still major gaps in basic, clinical and translational knowledge; thus, further research, with a focus on vulnerable populations, is needed to better characterize, detect and effectively treat all forms of pulmonary hypertension.

Post tuberculosis lung disease and tuberculosis sequelae: A narrative review

Post Tuberculosis lung disease (PTLD) and post tuberculosis sequelae is a global and poorly recognized problem, amplified by social factors and immunocompromising conditions, inadequate treatment, lack of effective prevention of tuberculosis (TB) infection and disease. As a disease, it remained until recently poorly defined, with studies heterogenous with regards to regions, population demographics, risk factors, cohort sizes, and methods. Pathophysiologically, even successfully treated pulmonary TB disease has sequelae i.e. involving central and peripheral airways, lung parenchyma and pleura, resulting in airway narrowing and dilatation, fibrocavitation and emphysema, pulmonary vascular changes as well as pleural fibrosis. Functionally patients have airflow limitation, restrictive disease or a mixture of both not rarely associated with respiratory, or even ventilatory failure. Quality of life is often impaired through disability, TB relapse, superinfections and through increased susceptibility to reinfection and persistent inflammation, leading to progressive lung function decline and an increased risk of cardiovascular disease and cancer. Premature mortality due to PTLD is very likely, but poorly described.

Outcomes of patients with elevated pulmonary artery systolic pressure on echocardiography due to chronic lung diseases

BACKGROUND

Pulmonary hypertension is associated with increased mortality, and lung diseases are the second most common cause of pulmonary hypertension. We aimed to evaluate the prognostic value of echocardiography in low-middle income countries where right heart catheterization is difficult to perform.

METHODS

This retrospective chart review study included adult patients hospitalized from June 2012 to May 2021, with a pulmonary artery systolic pressure (PASP) of ≥35 mmHg on echocardiography. The control arm consisted of patients with similar lung diseases who did not have an elevated PASP.

RESULTS

The study and control arm consisted of 128 patients each, with both groups having similar lung diseases. Obesity hypoventilation syndrome was the most common etiology of elevated PASP (28.1 %), followed by pulmonary embolism (20.3 %). The overall 1-year mortality of the study cohort, after diagnosis of elevated PASP, was 20.3 %. The control cohort with normal PASP had a 1-year mortality of 4.7 %. In the study cohort, patients with bronchiectasis had the highest cause-specific 1-year mortality (45.5 %). In the normal PASP cohort, the highest cause-specific 1-year mortality was observed in patients with interstitial lung disease (13.0 %). One-year hospital readmission was observed in 46.9 % and 33.6 % of patients in the study and control arms, respectively. On multivariate analysis, increased odds of 1-year mortality were observed in patients with elevated PASP, patients with 1-year hospital readmission, and in patients with interstitial lung disease or bronchiectasis.

CONCLUSION

Elevated PASP on echocardiography may be a prognostic factor for mortality in patients with chronic lung diseases.

Real-world evidence to advance knowledge in pulmonary hypertension: Status, challenges, and opportunities. A consensus statement from the Pulmonary Vascular Research Institute's Innovative Drug Development Initiative's Real-world Evidence Working Group

This manuscript on real-world evidence (RWE) in pulmonary hypertension (PH) incorporates the broad experience of members of the Pulmonary Vascular Research Institute's Innovative Drug Development Initiative Real-World Evidence Working Group. We aim to strengthen the research community's understanding of RWE in PH to facilitate clinical research advances and ultimately improve patient care. Herein, we review real-world data (RWD) sources, discuss challenges and opportunities when using RWD sources to study PH populations, and identify resources needed to support the generation of meaningful RWE for the global PH community.

Health Care Disparities in Pulmonary Arterial Hypertension

The current approach for the management of pulmonary arterial hypertension (PAH) relies on data gathered from clinical trials and large registries. However, there is concern that minorities including Black, Indigenous, and People of Color are underrepresented in these trials and registries, making current data not generalizable to these groups of patients. Hence, it is important to discuss the significance of race/ethnicity and socioeconomic factors in patients with PAH. Here, we review the current knowledge on health care disparities in PAH. We also propose future steps in the global task of assuring justice and equality in access to pulmonary hypertension health care.

HIV status and survival of patients with pulmonary hypertension due to left heart disease: the Pan African Pulmonary Hypertension Cohort

In sub-Saharan Africa, little is known about pulmonary hypertension in left heart disease (PH-LHD). We used multivariate logistic and cox-hazard proportional regression models to examine factors associated with increased right ventricular systolic pressure (RVSP) and the effect of real-world HIV status scenarios on 6-month survival rate in the Pan African Pulmonary Hypertension Cohort (PAPUCO) study, a prospective cohort from four African countries. Exposure to biomass fuel smoke (aOR, 95%CI 3.07, 1.02-9.28), moderate to severe NYHA/FC III/IV (aOR, 95%CI 4.18, 1.01-17.38), and unknown HIV status (aOR, 95%CI 2.73, 0.96-7.73) predicted moderate to severe RVSP at the time of presentation. Six months later, HIV infection, moderate-to-severe NYHA/FC, and alcohol consumption were associated with decreased survival probabilities. Upon adjusting for HIV infection, it was observed that an incremental rise in RVSP (1 mmHg) and inter-ventricular septal thickness (1 mm) resulted in an 8% (aHR, 95%CI 1.08, 1.02-1.13) and 20% (aHR, 95%CI 1.2, 1.00-1.43) increase in the probability of mortality due to PH-LHD. In contrast, the risk of death from PH-LHD was reduced by 23% for each additional unit of BMI. (aHR, 95%CI 0.77, 0.59-1.00). In conclusion, the present study offers insights into the determinants that are notably linked to unfavorable survival outcomes in patients with pulmonary hypertension due to left heart disease. Certain factors identified in this study are readily evaluable and amenable to modification, even in settings with limited resources.

Characteristics, Long-term Survival, and Risk Assessment of Pediatric Pulmonary Arterial Hypertension in China: Insights From a National Multicenter Prospective Registry

BACKGROUND

Registry-based studies of pediatric pulmonary arterial hypertension (PPAH) are scarce in developing countries, including China. The PPAH risk assessment tool needs further evaluation and improvement.

RESEARCH QUESTION

What are the characteristics and long-term survival of PPAH in China and what is the performance of the PPAH risk model in Chinese patients?

STUDY DESIGN AND METHODS

Patients with PAH were enrolled in the national prospective multicenter registry from August 2009 through December 2019. Children 3 months to 18 years of age at the time of PAH diagnosis were analyzed.

RESULTS

A total of 247 children with PAH were enrolled. The median patient age was 14.8 years, and 58.3% of patients were female. Most patients had a diagnosis of PAH associated with congenital heart disease (CHD; 61.5%) and idiopathic or heritable PAH (37.7%). The median time from symptom onset to PAH diagnosis was 24 months. The mean pulmonary artery pressure and pulmonary vascular resistance index were 70.78 ± 19.80 mm Hg and 21.82 ± 11.18 Wood Units·m2, respectively. Patients with CHD-associated PAH experienced a longer diagnostic delay and demonstrated higher pulmonary artery pressure, but better cardiac performance, than those with idiopathic or heritable PAH. An increased number of patients received targeted therapy at the last follow-up compared with baseline. The 5- and 10-year survival rates of the entire cohort were 74.9% and 55.7%, respectively, with better survival in patients with CHD-associated PAH than in those with idiopathic or heritable PAH. Patients with low risk had better survival than those with high risk according to the simplified noninvasive risk score model with weight, function class, and echocardiographic right ventricular size, both at baseline and follow-up.

INTERPRETATION

Patients with PPAH in China showed severely compromised hemodynamics with marked diagnostic delay. The long-term survival of PPAH is poor despite the increased usefulness of targeted drugs. The simplified noninvasive risk model demonstrated good performance for predicting survival in Chinese children with PAH.

TRIAL REGISTRY

ClinicalTrials.gov; No.: NCT01417338; URL: www.

CLINICALTRIALS

gov.

Fifty Years of Global Cardiovascular Research in Africa: A Scientometric Analysis, 1971 to 2021

Background To analyze the quantity and impact of cardiovascular research done in Africa or coauthored by researchers based in Africa, their determinants, and the patterns of research collaboration. Methods and Results We retrieved data from Web of Science and additional sources. We analyzed temporal trends from 1971 to 2021 and geographical distribution, research impact using country-level h-index, international research cooperation, and associations of research quantity and quality using linear regression. The annual volume of cardiovascular research from Africa has increased from 4 publications in 1971 to 3867 in 2020 and currently represents ~3% of the global cardiovascular research output. Authors from South Africa (28.1%) and Egypt (24.1%) accounted for more than half of all publications from African countries, and they had the highest h-index (209 and 111, respectively). Important collaborators outside Africa included the United States, United Kingdom, France, Germany, and Australia. The country's publication count was associated with larger population size (P<0.001), whereas the country's h-index was associated with larger population size (P=0.001) and higher human development index (P=0.023). International collaboration was dominated by the United States, South Africa, United Kingdom, Egypt, and Canada. The level of collaboration between African countries was lower than their collaboration with non-African countries. Conclusions Cardiovascular research output from African authors remains low, despite marked progress over the past 5 decades. These findings highlight the urgent need to improve the quantity and quality of cardiovascular research in Africa through increased investments, training of human resources, improved infrastructures, and expansion of collaborative research networks, particularly within Africa.

Long-Term Follow-up of Human Immunodeficiency Virus-Associated Pulmonary Hypertension: Clinical Features and Survival Outcomes of the Pan Africa Pulmonary Hypertension Cohort (PAPUCO)

Background

Data characterizing risk factors and long-term outcome studies on human immunodeficiency virus (HIV)-associated pulmonary hypertension (PH) in Africa are lacking.

Methods

The Pan African Pulmonary Hypertension Cohort, a multinational registry of 254 consecutive patients diagnosed with PH (97% of African descent) from 9 centers in 4 African countries was implemented. We compared baseline characteristics and 3-year survival of an HIV-infected cohort newly diagnosed with PH (PH/HIV+) to an HIV-uninfected cohort with PH (PH/HIV-).

Results

One hundred thirty-four participants with PH completed follow up (47 PH/HIV+ and 87 PH/HIV-; age median, 36 versus 44 years; P = .0004). Cardiovascular risk factors and comorbidities were similar except for previous tuberculosis (62% versus 18%, P < .0001). Six-minute walk distance (6MWD) <300 meters was common in PH/HIV- (P = .0030), but PH/HIV+ had higher heart (P = .0160) and respiratory (P = .0374) rates. Thirty-six percent of PH/HIV+ and 15% of PH/HIV- presented with pulmonary arterial hypertension (PAH) (P = .0084), whereas 36% of PH/HIV+ and 72% of PH/HIV- exhibited PH due to left heart disease (PHLHD) (P = .0009). Pulmonary hypertension due to lung diseases and hypoxia (PHLD) was frequent in PH/HIV+ (36% versus 15%) but did not reach statistical significance. Human immunodeficiency virus-associated PAH tended to have a poorer survival rate compared with PHLHD/PHLD in HIV-infected patients.

Conclusions

The PH/HIV + patients were younger and commonly had previous tuberculosis compared to PH/HIV- patients. Despite a better 6MWD at presentation, they had more signs and symptoms of early onset heart failure and a worse survival rate. Early echocardiography assessment should be performed in HIV-infected patients with history of tuberculosis who present with signs and symptoms of heart failure or posttuberculosis lung disease.

Identifying Potential Mitochondrial Proteome Signatures Associated with the Pathogenesis of Pulmonary Arterial Hypertension in the Rat Model

Pulmonary arterial hypertension (PAH) is a severe and progressive disease that affects the heart and lungs and a global health concern that impacts individuals and society. Studies have reported that some proteins related to mitochondrial metabolic functions could play an essential role in the pathogenesis of PAH, and their specific expression and biological function are still unclear. We successfully constructed a monocrotaline- (MCT-) induced PAH rat model in the present research. Then, the label-free quantification proteomic technique was used to determine mitochondrial proteins between the PAH group (n = 6) and the normal group (n = 6). Besides, we identified 1346 mitochondrial differentially expressed proteins (DEPs) between these two groups. Gene Ontology (GO) and the Kyoto Encyclopedia of Genes and Genomes (KEGG) were used to analyze the mainly mitochondrial DEPs' biological functions and the signal pathways. Based on the protein-protein interaction (PPI) network construction and functional enrichment, we screened 19 upregulated mitochondrial genes (Psmd1, Psmc4, Psmd13, Psmc2, etc.) and 123 downregulated mitochondrial genes (Uqcrfs1, Uqcrc1, Atp5c1, Atp5a1, Uqcrc2, etc.) in rats with PAH. Furthermore, in an independent cohort dataset and experiments with rat lung tissue using qPCR, validation results consistently showed that 6 upregulated mitochondrial genes (Psmd2, Psmc4, Psmc3, Psmc5, Psmd13, and Psmc2) and 3 downregulated mitochondrial genes (Lipe, Cat, and Prkce) were significantly differentially expressed in the lung tissue of PAH rats. Using the RNAInter database, we predict potential miRNA target hub mitochondrial genes at the transcriptome level. We also identified bortezomib and carfilzomib as the potential drugs for treatment in PAH. Finally, this study provides us with a new perspective on critical biomarkers and treatment strategies in PAH.

Prevalence, incidence, and survival of pulmonary arterial hypertension: A systematic review for the global burden of disease 2020 study

Pulmonary arterial hypertension (PAH) is characterized by increased resistance in the pulmonary arterioles as a result of remodeled blood vessels. We sought all available epidemiologic data on population‐based prevalence, incidence, and 1‐year survival of PAH as part of the Global Burden of Disease Study. We performed a systematic review searching Global Index Medicus (GIM) for keywords related to PAH between 1980 and 2021 and identified population‐representative sources of prevalence, incidence, and mortality for clinically diagnosed PAH. Of 6772 articles identified we found 65 with population‐level data: 17 for prevalence, 17 for incidence, and 58 reporting case fatality. Reported prevalence ranged from 0.37 cases/100,000 persons in a referral center of French children to 15 cases/100,000 persons in an Australian study. Reported incidence ranged from 0.008 cases/100,000 person‐years in Finland, to 1.4 cases/100,000 person‐years in a retrospective chart review at a clinic in Utah, United States. Reported 1‐year survival ranged from 67% to 99%. All studies with sex‐specific estimates of prevalence or incidence reported higher levels in females than males. Studies varied in their size, study design, diagnostic criteria, and sampling procedures. Reported PAH prevalence, incidence, and mortality varied by location and study. Prevalence ranged from 0.4 to 1.4 per 100,000 persons. Harmonization of methods for PAH registries would improve efforts at disease surveillance. Results of this search contribute to ongoing efforts to quantify the global burden of PAH.

Pulmonary Hypertension Registry of Kerala, India (PRO-KERALA): One-year outcomes

BACKGROUND

Short term outcomes of patients with pulmonary hypertension are not available from low and middle-income countries including India.

METHODS

We conducted a prospective study of 2003 patients with pulmonary hypertension, from 50 centres (PROKERALA) in Kerala, who were followed up for one year. Pulmonary hypertension (PH) was mainly diagnosed on the basis of Doppler echocardiography. The primary outcome was a composite end-point of all-cause death and hospital admission for heart failure. All cause hospitalisation events constituted the secondary outcome.

RESULTS

Mean age of study population was 56 ± 16 years. Group 1 and Group 2 PH categories constituted 21.2% and 59% of the study population, respectively. Nearly two-thirds (65%) of the study participants had functional class II symptoms. 31% of Group 1 PH patients were on specific vasodilator drugs.In total, 83 patients (4.1%) died during the one-year follow-up period. Further, 1235 re-hospitalisation events (61.7%) were reported. In the multivariate model, baseline NYHA class III/IV (OR 1.87, 95% C.I. 1.35-2.56), use of calcium channel blockers (OR 0.18, 95% C.I. 0.04-0.77), vasodilator therapy (OR 0.5, 95% C.I. 0.28-0.87) and antiplatelet agents (OR 1.80, 95% C.I. 1.29-2.51) were associated with primary composite outcome at one-year (p < 0.05).

CONCLUSION

In the PROKERALA registry, annual mortality rate was 4%. More than half of the patients reported re-hospitalisation events on follow up. Uptake of guideline directed therapies were suboptimal in the study population. Quality improvement programmes to improve guideline directed therapy may improve clinical outcomes of PH patients in India.

Pulmonary Hypertension in Children across Africa: The Silent Threat

Pulmonary hypertension (PH) is a complex puzzle in Africa, especially among children who present with a cocktail of issues including recurrent pulmonary infections, unoperated congenital heart disease, and advanced rheumatic heart disease. Sickle cell anemia and neonatal complications of transiting from fetal circulation also contribute to the burden of pulmonary hypertension. Mortality from pulmonary arterial hypertension (PAH) remains high in Africa (18-21%), claiming sufferers in the first 6 months after diagnosis. Unfortunately, PH remains underreported in sub-Saharan Africa since many centers lack the capacity to diagnose and confirm it by the recommended gold standard, right heart catheterization. The unresolved burden of unoperated congenital heart lesions and rheumatic heart disease, among other preventable causes, stand out as major causes of PH in African children. This paper highlights pediatric PAH as a result of major gaps in care and illustrates the need for its prevention as well as for the promotion of research into the most important drivers, to prevent premature mortality in the continent.

Targeting Molecular Inflammatory Pathways in Granuloma as Host-Directed Therapies for Tuberculosis

Globally, more than 10 million people developed active tuberculosis (TB), with 1.4 million deaths in 2020. In addition, the emergence of drug-resistant strains in many regions of the world threatens national TB control programs. This requires an understanding of host-pathogen interactions and finding novel treatments including host-directed therapies (HDTs) is of utter importance to tackle the TB epidemic. Mycobacterium tuberculosis (Mtb), the causative agent for TB, mainly infects the lungs causing inflammatory processes leading to immune activation and the development and formation of granulomas. During TB disease progression, the mononuclear inflammatory cell infiltrates which form the central structure of granulomas undergo cellular changes to form epithelioid cells, multinucleated giant cells and foamy macrophages. Granulomas further contain neutrophils, NK cells, dendritic cells and an outer layer composed of T and B lymphocytes and fibroblasts. This complex granulomatous host response can be modulated by Mtb to induce pathological changes damaging host lung tissues ultimately benefiting the persistence and survival of Mtb within host macrophages. The development of cavities is likely to enhance inter-host transmission and caseum could facilitate the dissemination of Mtb to other organs inducing disease progression. This review explores host targets and molecular pathways in the inflammatory granuloma host immune response that may be beneficial as target candidates for HDTs against TB.

Pulmonary hypertension in majority countries: opportunities amidst challenges

PURPOSE OF REVIEW

Pulmonary hypertension is a deadly disease, the causes of which vary between geographical regions. Eighty four percentage of the world's population lives in majority countries (also called low-income and middle-income countries), yet data on pulmonary hypertension in these settings are proportionally scarce. This article provides a review of pulmonary hypertension in majority countries, focusing in detail on the most common causes in these regions, and highlights contextual challenges faced.

RECENT FINDINGS

Epidemiological data confirms a complex and overlapping array of causes, with pulmonary hypertension because of conditions such as rheumatic heart disease, HIV, schistosomiasis, chronic lung disease and sickle cell disease. Delayed pulmonary hypertension diagnosis remains a concern and is ascribed to a lack of resources and lack of pulmonary hypertension awareness by health professionals. Pulmonary hypertension diagnosis is frequently considered once signs of right heart failure emerge, while echocardiography and right heart catheterization are unavailable in many settings. Accurate data on the prevalence of pulmonary hypertension in many of these regions are needed and could be achieved by establishing and frequent review of national databases where the incident and prevalent pulmonary hypertension cases are captured.

SUMMARY

There is urgent need for pulmonary hypertension advocacy among clinicians in the primary, secondary and tertiary healthcare sectors of majority countries, and validated noninvasive diagnostic algorithms are needed. Increased awareness and early diagnosis are likely to improve outcomes of pulmonary hypertension patients in these regions, and potentially stimulate locally relevant research.

SARS-CoV 2 Infection (Covid-19) and Cardiovascular Disease in Africa: Health Care and Socio-Economic Implications

The current pandemic of SARS-COV 2 infection (Covid-19) is challenging health systems and communities worldwide. At the individual level, the main biological system involved in Covid-19 is the respiratory system. Respiratory complications range from mild flu-like illness symptoms to a fatal respiratory distress syndrome or a severe and fulminant pneumonia. Critically, the presence of a pre-existing cardiovascular disease or its risk factors, such as hypertension or type II diabetes mellitus, increases the chance of having severe complications (including death) if infected by the virus. In addition, the infection can worsen an existing cardiovascular disease or precipitate new ones. This paper presents a contemporary review of cardiovascular complications of Covid-19. It also specifically examines the impact of the disease on those already vulnerable and on the poorly resourced health systems of Africa as well as the potential broader consequences on the socio-economic health of this region.

Pulmonary hypertension: Spectrum of disease, clinical presentation and treatment outcomes at the main respiratory pulmonary hypertension clinic in KwaZulu-Natal Province, South Africa

BACKGROUND

There are many causes of pulmonary hypertension (PH). However, the aetiology, management and treatment outcomes in South Africa (SA), which has a high burden of HIV, are lacking in the literature.

OBJECTIVES

To characterise patient demographics, aetiology, clinical presentation and management of patients presenting to the only government-funded PH clinic in Durban, SA.

METHODS

We retrospectively reviewed electronic charts of patients with confirmed PH who attended the respiratory PH clinic between 2011 and 2018. Demographic and clinical data, symptoms, pulmonary function testing, pulmonary artery pressure on echocardiography and treatment were analysed. Patients with group 2 PH were excluded from the present study as they were managed by cardiologists.

RESULTS

We identified 93 patients with confirmed PH and the majority were female (82.8%; n=77). The majority of the patients were between the ages of 30 and 39 years at the time of diagnosis. Most patients were black African (64.5%; n=60), followed by Indians (26.9%; n=25) and whites (8.6%; n=8). The most common cause of PH was group 1 (75%; n=70), followed by group 4 (13%; n=12) and then group 3 (12%; n=11). HIV-associated PH accounted for 27% of all patients and was the main cause of PH in those classified in group 1 (38%; n=29). Two-thirds (66%) of patients were treated with sildenafil, the only treatment that was available. Patients on treatment showed significant improvement indicated by the World Health Organization functional class, mean 6-minute walk test and reduction in mean pulmonary artery pressure on echocardiography.

CONCLUSION

HIV-associated PH is the most common cause of PH in SA. Sildenafil, the only drug available in our setting, is beneficial to most patients with PH.

Challenges and Special Aspects of Pulmonary Hypertension in Middle- to Low-Income Regions: JACC State-of-the-Art Review

Challenges and special aspects related to the management and prognosis of pulmonary hypertension (PH) in middle- to low-income regions (MLIRs) range from late presentation to comorbidities, lack of resources and expertise, cost, and rare options of lung transplantation. Expert consensus recommendations addressing the specific challenges for prevention and therapy of PH in MLIRs with limited resources have been lacking. To date, 6 MLIR-PH registries containing mostly adult patients with PH exist. Importantly, the global prevalence of PH is much higher in MLIRs compared with high-income regions: group 2 PH (left heart disease), pulmonary arterial hypertension associated with unrepaired congenital heart disease, human immunodeficiency virus, or schistosomiasis are highly prevalent. This consensus statement provides selective, tailored modifications to the current PH guidelines to address the specific challenges faced in MLIRs, resulting in the first pragmatic and cost-effective consensus recommendations for PH care providers, patients, and their families.

HIV X4 Variants Increase Arachidonate 5-Lipoxygenase in the Pulmonary Microenvironment and are associated with Pulmonary Arterial Hypertension

Pulmonary Arterial Hypertension (PAH) is overrepresented in People Living with Human Immunodeficiency Virus (PLWH). HIV protein gp120 plays a key role in the pathogenesis of HIV-PAH. Genetic changes in HIV gp120 determine viral interactions with chemokine receptors; specifically, HIV-X4 viruses interact with CXCR4 while HIV-R5 interact with CCR5 co-receptors. Herein, we leveraged banked samples from patients enrolled in the NIH Lung HIV studies and used bioinformatic analyses to investigate whether signature sequences in HIV-gp120 that predict tropism also predict PAH. Further biological assays were conducted in pulmonary endothelial cells in vitro and in HIV-transgenic rats. We found that significantly more persons living with HIV-PAH harbor HIV-X4 variants. Multiple HIV models showed that recombinant gp120-X4 as well as infectious HIV-X4 remarkably increase arachidonate 5-lipoxygenase (ALOX5) expression. ALOX5 is essential for the production of leukotrienes; we confirmed that leukotriene levels are increased in bronchoalveolar lavage fluid of HIV-infected patients. This is the first report associating HIV-gp120 genotype to a pulmonary disease phenotype, as we uncovered X4 viruses as potential agents in the pathophysiology of HIV-PAH. Altogether, our results allude to the supplementation of antiretroviral therapy with ALOX5 antagonists to rescue patients with HIV-X4 variants from fatal PAH.

Multimorbidity and cardiovascular disease: a perspective on low- and middle-income countries

New and changing patterns of multimorbidity (MM), i.e., multiple concurrent acute or chronic diseases in a person, are emerging in low- and middle-income countries (LMICs). The interplay of underlying population-specific factors and lifestyle habits combined with the colliding epidemics of communicable and non-communicable diseases presents new disease combinations, complexities and risks that are not common in high-income countries (HICs). The complexities and risks include those arising from potentially harmful drug-drug and drug-disease interactions (DDIs), the management of which may be considered as MM in the true sense. A major concern in LMICs is the increasing burden of leading cardiovascular diseases, prevalence of associated risk factors and co-occurrence with other morbidities. New models of MM management and integrated care can respond to the needs of specific multimorbid populations, with some LMICs making substantial progress (e.g., integration of tuberculosis and HIV services in South Africa). But there is a dearth of relevant data on the changing patterns and underlying factors and determinants of MM, the associated complexities and risks of DDIs in MM management, and the barriers to integrated care in LMICs. This requires careful attention.

Pulmonary hypertension in low- and middle-income countries with focus on sub-Saharan Africa

Pulmonary hypertension (PH) is a devastating, progressive disease with increasingly debilitating symptoms and usually shortened overall life expectancy. This article reviews the global epidemiology of PH with focus on low- and middle-income countries (LMICs) and sub-Sahara African in particular. Although left ventricular heart disease is the most common cause globally, the main contributing risk factors in LMICs are chronic infectious diseases especially human immunodeficiency virus (HIV) and schistosomiasis. Other important risk factors of PH are rheumatic heart disease, untreated congenital heart disease (CHD), and sickle cell disease. Despite existing epidemiological data of PH risk factors suggesting a high prevalence in sub-Saharan Africa (SSA), the available literature is limited. International registries in LMICs like the pan African pulmonary hypertension cohort (PAPUCO) study are essential to provide information about the causes, treatment, outcome, and the natural course of PH in Africa and other parts of the world. In addition, there is a need to track diagnostic and management practices in order to develop suitable algorithms to diagnose PH in LMICs.

Cardiovascular Diseases in Sub-Saharan Africa Compared to High-Income Countries: An Epidemiological Perspective

Non-communicable diseases (NCDs) are the second common cause of death in sub-Saharan Africa (SSA) accounting for about 35% of all deaths, after a composite of communicable, maternal, neonatal, and nutritional diseases. Despite prior perception of low NCDs mortality rates, current evidence suggests that SSA is now at the dawn of the epidemiological transition with contemporary double burden of disease from NCDs and communicable diseases. In SSA, cardiovascular diseases (CVDs) are the most frequent causes of NCDs deaths, responsible for approximately 13% of all deaths and 37% of all NCDs deaths. Although ischemic heart disease (IHD) has been identified as the leading cause of CVDs mortality in SSA followed by stroke and hypertensive heart disease from statistical models, real field data suggest IHD rates are still relatively low. The neglected endemic CVDs of SSA such as endomyocardial fibrosis and rheumatic heart disease as well as congenital heart diseases remain unconquered. While the underlying aetiology of heart failure among adults in high-income countries (HIC) is IHD, in SSA the leading causes are hypertensive heart disease, cardiomyopathy, rheumatic heart disease, and congenital heart diseases. Of concern is the tendency of CVDs to occur at younger ages in SSA populations, approximately two decades earlier compared to HIC. Obstacles hampering primary and secondary prevention of CVDs in SSA include insufficient health care systems and infrastructure, scarcity of cardiac professionals, skewed budget allocation and disproportionate prioritization away from NCDs, high cost of cardiac treatments and interventions coupled with rarity of health insurance systems. This review gives an overview of the descriptive epidemiology of CVDs in SSA, while contrasting with the HIC and highlighting impediments to their management and making recommendations.

Long-Term Outcomes and Factors Associated with Mortality in Patients with Moderate to Severe Pulmonary Hypertension in Kenya

Background:

Pulmonary hypertension is poorly studied in Africa. The long-term survival rates and prognostic factors associated with mortality in patients with moderate to severe pulmonary hypertension (PH) in Africa are not well described.

Objectives:

To determine the causes of moderate to severe PH in patients seen in contemporary hospital settings, determine the patients’ one-year survival and the factors associated with mortality following standard care.

Methods:

A retrospective review of patients diagnosed with moderate to severe PH at Aga Khan University Hospital (AKUHN) from August 2014 to July 2017 was carried out. Clinical and outcome data were collected from medical records and the hospital mortality database. Telephone interviews were conducted for patients who died outside the hospital. Survival analysis was done using Kaplan-Meier, and log-rank tests were used to assess differences between subgroups. Cox regression modelling with multivariable adjustment was used to identify factors associated with all-cause mortality.

Results:

A total of 659 patients with moderate to severe PH were enrolled. Median follow-up time was 626 days. The survival rates of the patients at 1 and 2 years were 73.8% and 65.9%, respectively. The following variables were significantly associated with mortality: diabetes mellitus [adjusted HR 1.52, 95% CI (1.14–2.01)], WHO functional class III/IV [adjusted HR 3.49, 95% CI (2.46–4.95)], atrial fibrillation [adjusted HR 1.53, 95% CI (1.08–2.17)], severe PH [adjusted HR 1.72, 95% CI (1.30–2.27)], right ventricular dysfunction [adjusted HR 2.42, 95% CI (1.76–3.32)] and left ventricular dysfunction [adjusted HR 1.91, 95% CI (1.36–2.69)]. Obesity [adjusted HR 0.68, 95% CI (0.50–0.93)] was associated with improved survival.

Conclusion:

Pulmonary hypertension is associated with poor long-term outcomes in African patients. Identification of prognostic factors associated with high-risk patients will assist in patient management and potentially improved outcomes.

Moving Ahead: Building a Strong Network Among Female Cardiovascular Clinician Scientists and Researchers in Africa

This case reports on the authors' successes building a strong network among female cardiovascular clinician scientists and researchers in Africa provides examples of collaborations and mentorship. (Level of Difficulty: Beginner.).

Pulmonary arterial hypertension and the potential roles of metallothioneins: A focused review

The pathophysiology of pulmonary arterial hypertension (PAH) is underlined by cell proliferation and vasoconstriction of pulmonary arterioles this involves multiple molecular factors or proteins, but it is not clear what the exact roles of these factors/proteins are. In addition, there may be other factors/proteins that have not been identified that contribute to PAH pathophysiology. Therefore, research has focused on investigating novel role players, in order to facilitate a better understanding of how PAH develop. Evidence suggest that mitochondrial regulators are key role players in PAH pathophysiology, but regulators that have not received sufficient attention in PAH are metallothioneins (MTs). In PAH patients, MT expression is elevated compared to healthy individuals, suggesting that MTs may be possible biomarkers. In other disease-models, MTs have been shown to regulate cell proliferation and vasoconstriction, processes that are instrumental in PAH pathophysiology. Due to the involvement of these processes in PAH pathophysiology and the ability of MTs to modulate them, this paper propose that cellular MTs may also play a role in PAH development. This paper suggests that PAH-research should perhaps begin to investigate the involvement of cellular MTs in the development of PAH.

Pulmonary hypertension as seen in a rural area in sub-Saharan Africa: high prevalence, late clinical presentation and a high short-term mortality rate during follow up

INTRODUCTION

The epidemiology of pulmonary hypertension (PH) in low- to middle-income countries is poorly characterised. We assessed the prevalence, baseline characteristics and mortality rate in patients with echocardiographically diagnosed PH at a rural cardiac centre in Cameroon.

METHODS

We conducted a prospective cohort study in a subsample of 150 participants, aged 18 years and older, diagnosed with PH [defined as right ventricular systolic pressure (RVSP) ≥ 35 mmHg in the absence of pulmonary stenosis and right heart failure]. PH was classified as mild (RVSP: 35-50 mmHg), moderate (RVSP: 51-60 mmHg) and severe (RVSP: > 60 mmHg).

RESULTS

Of 2 194 patients screened via echocardiograms, 343 (crude prevalence 15.6%) had PH. The sub-sample of 150 patients followed up (54.7% women, mean age of 62.7 ± 18.7 years) had a mean RVSP of 68.6 mmHg. They included 7.3% mild, 29.3% moderate and 63.4% severe PH cases. Co-morbidities included log smoke (80.7%), hypertension (52.0%), family history of cardiovascular disease (50.0%), diabetes (31.3%), alcohol abuse (21.3%) and HIV infection (8.7%). Main clinical features were dyspnoea (78.7%), fatigue (76.7%), palpitations (57.3%), cough (56.7%), jugular venous distension (68%) and peripheral oedema (66.7%). Overall, 70% presented in World Health Organisation functional class III/IV. PH due to left heart disease (PHLHD) was the commonest (64.7%), and rheumatic valvular disease accounted for 36.1%. The six-month mortality rate was 28%.

CONCLUSION

PH, dominated by PHLHD, was common among adults attending this rural centre and was associated with a high mortality rate. Related co-morbidities and late clinical presentation reflect the poor socio-economic context. Improved awareness of PH among physicians could promote early diagnosis and management.

Prevalence and etiologies of pulmonary hypertension in Africa: a systematic review and meta-analysis

BACKGROUND

Despite the recent increasing worldwide attention towards pulmonary hypertension (PH), its epidemiology remains poorly described in Africa. Accordingly, we performed a systematic review and meta-analysis of PH prevalence, incidence and etiologies in Africa.

METHODS

We searched PubMed, EMBASE, African Journals Online, and Africa Index Medicus. Published observational studies until September 20, 2017, including adult participants residing in Africa were considered. Two review authors independently selected studies, assessed included studies for methodological quality, and extracted data. A random-effects model was used for meta-analysis. Heterogeneity was evaluated by the χ 2 test on Cochrane's Q statistic which is quantified by I2 values. Using Newcastle-Ottawa Scale, we considered a score of 0-4, 5-7, and 8-10 as indicative of high, moderate, and low risk of bias in included studies, respectively.

RESULTS

Of 1611 entries, 25 studies were retained. Twelve (48%), seven (28%), and six (24%) papers had respectively a low, moderate and high risk of bias. The prevalence of PH widely varied across different populations: 9.8% (95% confidence interval: 3.2-19.3; I2 = 99.4%; 6 studies) in 11,163 people presenting with cardiac complaints; 10.6% (4.3-19.1; I2 = 90.3%; 4 studies) in 937 HIV-infected people; 32.9% (17.6-50.4; I2 = 97.2%; 3 studies) in 2077 patients with heart failure; 23.2% (15.2-32.2; I2 = 59.4%; 3 studies) in 248 patients on hemodialysis; 12.9% (11.8-14.0; I2 = 79.7%; 2 studies) in 3750 patients with rheumatic heart disease; 36.9% (29.7-44.3; I2 = 79.7; 2 studies) in 79 patients with sickle cell disease; 62.7% (49.0-74.7; 1 study) in 51 patients with chronic obstructive pulmonary disease; 25.4% (16.3-37.3; 1 study) in 63 patients with systemic lupus erythematous; 68.7% (62.8-74.1; 1 study) in 259 patients with cardiac surgery; and 7.4% (4.6-11.9; 1 study) in 202 patients with systemic sclerosis. No study reported PH incidence. From one international study (n = 209), PH etiologies were: left heart disease (68.9%), pulmonary arterial hypertension (15.8%), lung disease and/or hypoxia (12.0%), chronic thromboembolic PH (1.9%) and unclear/multifactorial PH (15.8%).

CONCLUSION

The prevalence of PH is relatively high in some populations in Africa, perhaps mainly driven by left heart diseases, highlighting the need for context-specific interventions.

Prevalence, incidence and aetiologies of pulmonary hypertension in Africa: a systematic review and meta-analysis protocol

INTRODUCTION

There are no data summarising the epidemiology of pulmonary hypertension (PH) among adults residing in Africa. Establishment of accurate epidemiological data on PH in this region may guide decision-making toward interventions to curb the burden of PH in Africa. The aim of this systematic review is to determine the prevalence, incidence and aetiologies of PH among people residing in Africa.

METHODS AND ANALYSIS

This systematic review and meta-analysis will follow the MOOSE guidelines for reporting. Relevant abstracts published until 30 September 2016 will be searched in PubMed/Medline, EMBASE (Excerpta Medica Database), African Journals Online and Africa Index Medicus. Full texts of eligible studies will then be accessed through PubMed, Google Scholar, HINARI and the respective journals' websites. Relevant unpublished papers and conference proceedings will also be checked. Data will be analysed using STATA version 13 software. The study-specific estimates will be pooled through a random-effects meta-analysis model to obtain an overall summary estimate of the prevalence/incidence and aetiologies of PH across studies. Heterogeneity of studies will be evaluated by the χ² test on Cochrane's Q statistic. Funnel plot analysis and Egger's test will be done to detect publication bias. Results will be presented by geographical region (central, eastern, northern, southern and western Africa).

ETHICS AND DISSEMINATION

The current study is based on published data; ethical approval is, therefore, not required. This review will guide policy, practice and research by providing information on the magnitude of PH among people residing in Africa. Findings will be presented in evidence tables of individual studies as well as in summary tables. The final report of this systematic review, in the form of a scientific paper, will be published in a peer-reviewed journal. Furthermore, findings will be presented at conferences and submitted to relevant health authorities.

REVIEW REGISTRATION NUMBER

PROSPERO CRD42016049351.

Cardiovascular disease in Africa: epidemiological profile and challenges

From a global perspective, the large and diverse African population is disproportionately affected by cardiovascular disease (CVD). The historical balance between communicable and noncommunicable pathways to CVD in different African regions is dependent on external factors over the life course and at a societal level. The future risk of noncommunicable forms of CVD (predominantly driven by increased rates of hypertension, smoking, and obesity) is a growing public health concern. The incidence of previously rare forms of CVD such as coronary artery disease will increase, in concert with historically prevalent forms of disease, such as rheumatic heart disease, that are yet to be optimally prevented or treated. The success of any strategies designed to reduce the evolving and increasing burden of CVD across the heterogeneous communities living on the African continent will be dependent upon accurate and up-to-date epidemiological data on the cardiovascular profile of every major populace and region. In this Review, we provide a contemporary picture of the epidemiology of CVD in Africa, highlight key regional discrepancies among populations, and emphasize what is currently known and, more importantly, what is still unknown about the CVD burden among the >1 billion people living on the continent.

The heart of Africa: succeeding against the odds

South Africa and other areas of sub-Saharan Africa have in the past 20 years undergone rapid demographical changes, largely due to urbanisation and changes in lifestyle. This rapid change has led to a marked increase in specific cardiac conditions, such as hypertensive heart disease and coronary artery disease (with the highest prevalence in the middle-aged population), in conjunction with a range of other heart diseases, which are historically common in Africa-eg, rheumatic heart disease, cardiomyopathies, and unoperated congenital heart disease. The short supply of well-equipped screening facilities, late diagnosis, and inadequate care at primary, secondary, and tertiary levels have led to a large burden of patients with poorly treated heart failure. Excellent progress has been made in the understanding of the epidemiology, sociodemographical factors, effect of urbanisation, and pathophysiology of cardiac conditions, such as peripartum cardiomyopathy, rheumatic heart disease, and tuberculous pericarditis, which are common in sub-Saharan Africa. This progress has been achieved largely through several studies, such as the Heart of Soweto, THESUS, REMEDY, BA-HEF, Abeokuta-HF, and the PAPUCO studies. Studies on the suitable therapeutic management of several heart conditions have also been done or are underway. In this Lecture, I provide a personal perspective on the evolving burden of cardiac disease, as witnessed since my appointment at Chris Hani Baragwanath Hospital, in Soweto, South Africa, in 1992, which was also the year that the referendum to end apartheid in South Africa was held. Subsequently, a network of cardiologists was formed under the umbrella of the Heart of Africa Studies and the Pan African Cardiac Society. Furthermore, I summarise the major gaps in the health-care system dealing with the colliding epidemic of communicable and non-communicable heart diseases, including cardiac diseases common in peripartum women. I also touch on the fantastic opportunities available for doing meaningful research with enthusiastic colleagues and, thereby, having a large effect, despite the need to be highly innovative in finding much needed funding support.