|Year : 2020 | Volume
| Issue : 1 | Page : 27-36
Rheumatic heart disease in Nigeria: A review
Okechukwu S Ogah1, Fidelia Bode-Thomas2, Christopher Yilgwan2, Olukemi Ige2, Fisayo Ogah3, Oluwatoyin O Ogunkunle4, Chimezie Okwuonu5, Mahmoud Sani6
1 Division of Cardiology, Department of Medicine, University of Ibadan, Oyo State, Nigeria
2 Department of Paediatrics, University of Jos, Plateau State, Nigeria
3 Department of Chemical Pathology, University College Hospital, Ibadan, Nigeria
4 Department of Paediatrics, College of Medicine, University of Ibadan, Ibadan, Oyo State, Nigeria
5 Department of Internal Medicine, Federal Medical Centre, Umuahia, Abia State, Nigeria
6 Department of Medicine, Bayero University, Kano, Kano State, Nigeria
|Date of Submission||17-Nov-2019|
|Date of Acceptance||21-Nov-2019|
|Date of Web Publication||30-Jun-2020|
Dr. Okechukwu S Ogah
Department of Medicine, Division of Cardiology, University of Ibadan/ University College Hospital, P.O Box 14343 ,UI Post Office Ibadan, Oyo State
Source of Support: None, Conflict of Interest: None
Rheumatic heart disease (RHD) is a major public health problem in resource-poor countries, especially in sub-Saharan Africa where about 1 million affected children between 5 and 14 years of age live with the disease. The aim of this paper is to review current knowledge on the clinical epidemiology of RHD in Nigeria, identify gaps, and suggest possible future directions. A systematic literature search was conducted using African Journal online (AJOL), Cinahl, Google Scholar, PubMed, and Web of Science. In PubMed, the following medical subject headings and free text terms were used: “Rheumatic heart disease” OR “Rheumatic “Valvular heart disease” OR “Rheumatic fever” AND “Nigeria”. The same text word search was used in Google scholar, AJOL, CINAHL, and Web of Science. A search date was limited to articles published from January 1950 to December, 2018. A total of 44 original studies were reviewed. Nineteen (45.2%) of the studies used clinical criteria for diagnosis of RHD, 19 (40.5%) used echocardiographic diagnosis, and 6 (14.3%) used autopsy or post mortem examination of the patients for the diagnosis of RHD. Five (11.9%) of the studies were conducted in children only, 9 (16.7%) were in both children and adults, and the remaining 31 (73.8%) were done in adults only. Only 6 (14.3%) of the studies reported complications seen in patients with RHD. Of the 6 studies that reported on complications, only 1 reported on recurrent of acute rheumatic fever. Mitral valvular disease was the most common lesion reported in all the studies. RHD still remains a major cardiovascular health problem in Nigeria. There is therefore a need for more recent clinical studies on the contemporary pattern of RHD in Nigeria. In addition, community based screening for RHD is needed to determine the true burden of the disease in Nigeria. Finally, primary and secondary preventive measures are needed to help reduce the burden of RHD in Nigeria.
Keywords: Heart disease, Nigeria, rheumatic fever, rheumatic heart disease
|How to cite this article:|
Ogah OS, Bode-Thomas F, Yilgwan C, Ige O, Ogah F, Ogunkunle OO, Okwuonu C, Sani M. Rheumatic heart disease in Nigeria: A review. Nig J Cardiol 2020;17:27-36
|How to cite this URL:|
Ogah OS, Bode-Thomas F, Yilgwan C, Ige O, Ogah F, Ogunkunle OO, Okwuonu C, Sani M. Rheumatic heart disease in Nigeria: A review. Nig J Cardiol [serial online] 2020 [cited 2023 Apr 2];17:27-36. Available from: https://www.nigjcardiol.org/text.asp?2020/17/1/27/288651
| Introduction|| |
Rheumatic heart disease (RHD), a disease of social disadvantage, is a clinical condition caused by rheumatic fever (RF); an autoimmune reaction to infection with Group A beta-hemolytic streptococcus. Although infectious in origin, RHD is now recognized as a chronic noncommunicable disease. This is because RHD, a disease characterized by severe valve damage, usually leads to chronic heart failure (HF), chronic atrial fibrillation (AF), and thromboembolic complications such as stroke.
It is estimated that 33 million people have RHD worldwide., Furthermore, approximately 319,400 individuals died from RHD in 2015, while about 471,000 new cases were diagnosed annually. RHD is also the most common cause of cardiovascular disease (CVD) in young people aged 25 years or below, majority of whom live in Africa, the South Pacific, Middle East, Central, and South Asia. It afflicts them in their most productive years with associated high mortality and high disability-adjusted life years. It is also a major contributor to maternal and perinatal mortality in the aforementioned regions. RHD was once common in high income countries, however by the 1980s, the condition had been almost eliminated in these countries.
The lesson from high-income countries and some developing countries is that the disease can be controlled through comprehensive, register-based RHD control programs. The World Health Organization has launched a 25 × 25 <25 campaign which calls for multisectoral action to reduce premature CVD mortality by 25% by the year 2025. The global body is optimistic that within this adopted framework, the mortality associated with RHD can be reduced by 25% by 2025 for individuals under the age of 25 years (25 × 25 <25).
In Nigeria, the true burden of the disease is not known, and there is limited population based data for informed decision-making. According to WHO, the country belongs to the group of countries where it is estimated that between 1000 and 4999 people died from the disease in 2002.
The aim of this paper is to review current knowledge on the clinical epidemiology of RHD in Nigeria, identify gaps and suggest possible future directions.
| Methods|| |
A PubMed search was conducted from January 1, 1950, to December 31, 2018. The search criteria adopted were “Rheumatic Heart Disease,” “Valvular Heart Disease,” “Cardiac Failure,” “heart failure” AND “Nigeria,” Additional publications were sought from references of retrieved articles and other databases such as the African Journals Online and the African Index Medicus, African Index Medicus, CINHL, Google scholar and Web of Science).
The identified papers were classified into: hospital-based clinical studies on diseases leading to HF in Nigeria [Table 1],,,,,,,,, report on echocardiographic registries [Table 2],,,,,,, mortality and autopsy studies [Table 3],,,,,, specific studies on RHD [Table 4],,,,,,,,,,,,,,, and population based studies [Table 5].,,, In many of the publications, cases in children and adults were reported together.
|Table 1: Prevalence of rheumatic heart disease in clinical studies of heart disease/heart failure in Nigeria|
Click here to view
|Table 2: Prevalence of rheumatic heart disease in echocardiography registries in different parts of Nigeria|
Click here to view
|Table 3: Prevalence of rheumatic heart disease in autopsy or mortality studies|
Click here to view
Like high blood pressure, RHD was earlier thought to be uncommon in tropical and subtropical climate., “This assumption was to the extent of patients were being transferred to tropical countries in an attempt to improve or alter the progress of RF or its usual complications.”, Workers in India were the first to report that RHD constituted 20.5% of cardiac related conditions in a tropical/subtropical milieu.,, Thereafter, many investigators in other countries outside India (including Africa) also recognized RHD as an important cause of cardiac morbidity and mortality.,, RHD was recognized as responsible for 12.9%–40% of cardiac admissions in Africa.
The earliest publications on RHD in Nigeria were probably the reports in 1955 by Nwokolo in Eastern Nigeria and 1956 by Beet in Northern Nigeria. Beets examined all cardiac cases admitted to three main hospitals in Northern Nigeria (Kano, Kaduna, and Jos) and reported that RHD was responsible for 23% of cardiac conditions. Probably due to few data from Southern Nigeria at that time, he assumed that the high burden was only peculiar to Northern Nigeria and might not be applicable to coastal areas of West Africa However, subsequent work in Ibadan by Lauckner et al. using an analysis of medical admissions to the University College Hospital Ibadan in 1958, showed that acute carditis was responsible for about 18.7% of all cardiac admissions. Lauckner et al., therefore, concluded that with further experience as well as improved diagnostic facilities at the hospital, RHD was by no means uncommon in Nigeria. This was further reinforced by other workers from other parts of Nigeria.,,,,, The seminal work of Cole and Cole and Adeleye,, Antia and Jaiyesimi,,, at Ibadan, Ogunbi et al. and Fadahunsi et al.,, in Lagos and Okoroma in Enugu shaped our understanding of the clinical characteristics, profile, and natural history of this condition in Nigeria. Recent advances in the diagnosis of RHD, especially with the advent of echocardiography and its widespread availability in Nigeria, has improved our understanding of the epidemiology and spectrum of presentation of RHD.
Peculiarities of rheumatic heart disease in Nigeria
RHD is mainly a disease that begins in childhood. It has its peak incidence in children aged 5–15 years and young adults below the age of 30 years. Affected children in the absence of any intervention, progress to severe disease and eventually die before they reach adulthood. However, where the disease is milder or adequate care is available, affected children live with the disease carrying it into adulthood.
The general pattern of RHD in Nigeria is similar to the established pattern in many tropical and subtropical climates:,,,,,,,,,,, It is highly prevalent in the low socioeconomic class of the population with an infrequent and atypical nature of preceding history of RF in patients with established RHD. It is also associated with an early onset of established rheumatic valve disease and pulmonary hypertension, rapid progression of the disease, and frequent presentation as HF, especially in young adults. Furthermore, the comparatively low frequency of pure mitral stenosis (MS), the predominance of pure mitral regurgitation (MR) and mixed mitral valve lesions and a relatively low frequency of atrial fibrillation (AF) despite the severity of the mitral valve lesion was highlighted by earlier authors [Figure 1].,,,,,
|Figure 1: (a) Pattern of valve lesion in male children and, (b) in female children in Ibadan. Adapted from Jaiyesimi and Antia|
Click here to view
There are similarities in the presentation of the disease between children and adults in Nigeria though some differences in spectrum exist. In children, the disease mainly presents with chronic HF although anemia, respiratory tract infections and congenital heart disease are more frequent causes of HF in Nigerian children. In adults, our understanding of the disease stems from the retrospective and prospective studies of RHD undertaken by Cole and Ogunlesi in Ibadan in the 1970s and 1980s coupled with studies of heart disease in other centers in the country. RHD was demonstrated to be a common cause of HF in adults presenting to the cardiology clinic and emergency room,,,,, as seen in [Table 1]. This is however no longer the case.,, RHD was also shown to be responsible for 2.4% to 25.6% of diseases leading to adult HF in the country in that era.
In both children and adults, the disease is more common in females with a male to female ratio ranging from 1:1.2 to 1:2.0,,,, The only exception is the small sample reported by Akpa et al. from Port-Harcourt. Women contributed between 50.3% and 70.9% of the burden of the disease in most of the series reported. The reason for higher prevalence in females is not fully known.
In one report, majority (71%) of the patients were in the 6–10 year age group, 10% were aged 3–5 years while those aged 11–15 years constituted 19%. In general, Nigerian children are susceptible to RHD between the ages of 3 and 15 years [Figure 2].,,, In many mixed studies,,, the mean age at presentation ranges from 26.6 to 27.6. years (range 12–70 years) [Table 4]. In a recent review of adult RHD cases in the Abeokuta Heart Disease Registry, a higher mean age of 43 years was reported. [Figure 3] shows age distribution of cases in the Abeokuta Heart Disease Registry.
|Figure 2: The mean age of presentation of childhood RHD and other conditions in Jos Nigeria (Adapted from Bode-Thomas et al.)|
Click here to view
|Figure 3: Findings in adult patients with Rheumatic fever in Ibadan in 1976 (a), and 1980 (b),|
Click here to view
Poverty and social disadvantage are important drivers and predisposing factors to the RHD scourge globally. Poverty and social disadvantage drive overcrowding, poor ventilation, malnutrition, poor sanitation and hygiene, and the poor access to healthcare associated with the development of RHD in Nigeria and elsewhere. This was classically demonstrated by Cole et al. in Ibadan where majority of their patients though living in urban and peri-urban areas of Ibadan, were from low socioeconomic quintiles. Similarly, the report by Jaiyesimi and Antia in 1981 on children from Ibadan showed that most of the children (90%) with RHD came from poor homes which were most often over-crowded. The number of siblings per patient ranged from 2 to 14, with a mean of 5. Recent reports still show the predominance of poverty and poverty related factors in families of patients with RHD in Nigeria.
RHD occurs after an episode or recurrent episodes of untreated or poorly treated acute RF. A past history of RF though relevant may not be readily volunteered or even remembered by many patients, especially adults with RHD. In addition, many people, especially children and adolescents affected with RHD present with severe HF as a result of severe valvular insufficiency resulting from chronic inflammation with deformed and fibrosed valvular apparatus, while the adults present with AF and embolic phenomenon in addition to the HF.
Early studies from Ibadan demonstrated previous history of RF in about 26% of the children studied, while 16% had fever, carditis, and raised anti-streptolysin–O (ASO) titer. Only about 8% had migratory polyarthritis while chorea and subcutaneous nodules were seen in only one patient of the 80 consecutive cases studied in the Ibadan series by Jaiyesimi and Antia. Three quarters of the children presented in NYHA classes III and IV. Only 6% and 19% presented in NYHA classes I and II, respectively.
Three quarters of the children presented in NYHA classes III and IV. Only 6% and 19% presented in NYHA classes I and II, respectively [Figure 4]. According to Antia, the possible explanations for the apparent rarity of RF included late presentation when the signs would have disappeared, custom, ignorance, traditional beliefs and socio-economic status of the people. Due to ignorance, parents may not relate the symptoms of HF in their children with any past history of RF. Some would deliberately withhold information of past history for fear of being scolded for not seeking medical care early.
|Figure 4: The age distribution of RHD patients in the Abeokuta Heart Disease registry|
Click here to view
Traditional beliefs often underlie the lack of faith in orthodox medical treatment. Parents of these children sought the advice of traditional healers first, and only resorted to orthodox care after exhausting other options. According to Antia, the Nigerian environment might also have played a role, as fever is often first treated as malaria, and joint swellings as cases of trauma.
Previous history of RF was obtained in 67 (41%) of 163 adult patients prospectively studied in Ibadan. Recurrence of rheumatic activity occurred in 60 (36.8%) cases. Those with evidence of active rheumatic activity were also found to be younger (mean age 18.4 years, range 12–35 years). Poly- or monoarthralgia were more common (rather than objective polyarthritis) with clinical evidence of active carditis.
According to recent data from Abeokuta, southwest Nigeria, most patients presented in advanced HF (NYHA functional class III and IV); 73.9% of patients were in NYHA classes III and IV. Only about 5% could recall having symptoms suggesting RF in the past and 8% had previous history of HF.
The common symptoms at presentation include cough (87.9%), easy fatigability (50.5), dyspnea on exertion (100%), orthopnea (100%), and paroxysmal nocturnal dyspnea (74.8%). Other symptoms include leg swelling (74.8%), palpitation (33.6%), chest pain (50.5%), hemoptysis (16.8%), and fever (7.5%). In terms of clinical signs, elevated jugular venous pressure (JVP), basal crepitations, displaced apex beat, and third heart sounds were common, occurring in 66.4%, 77.6%, 39.3%, 174.3%, and 5.8%, respectively. Other signs include diastolic murmur (8.4%), hepatomegaly (74.8), splenomegaly (8.4%), and ascites (33.6%).
Hospitalization in adult RHD in Nigeria is often precipitated by uncontrolled AF (25.8%), active rheumatic activity, superadded chest infection, infective endocarditis, pregnancy and cerebrovascular events. In the series by Onwuchekwa in Maiduguri (North Eastern Nigeria), about 28% presented during pregnancy while four percent presented with stroke.,
Pattern of valve disease
Pure MR is by far the most common valvular lesion in most adult series in Nigeria. It is responsible for 35% of cases. This is followed by mixed mitral value disease and pure MS in the order of frequency,,,, [Table 5] and [Figure 1].
The earlier clinical studies reported in Nigeria have consistently showed a predominance of mitral valve involvement similar to what has been reported globally. This trend has not changed over the years even with the advent of echocardiographic diagnosis, a tool which has improved the case detection of RHD thus improving our understanding of the spectrum and pattern of the disease. Jaiyesimi and Antia in their study of 86 children aged 3–15 years in the Ibadan, reported that single valve lesions (pure MR or MS) constituted about 59 (67%) of the cases while double valve lesions (MS/MR, MR/tricuspid regurgitation [TR], MR/aortic regurgitation [AR] and AR/aortic stenosis [AS]) were seen in a quarter. Triple disease (MR/MS/TR) and quadruplet lesions (MR/MS/AR/AS) were each recorded in 21 (24.4%) of cases. The remaining 6 patients had more than 2 valves involved.
Early onset of MS and rapid progression to HF was common. Earlier authors had attributed this to the predisposition of Africans to forming keloids. On the contrary, it has been shown that histological features of keloids and stenosed mitral valves are different.,,
The best explanation is that intense host reactions and recurrent RF were the major determinants of accelerated MS. In the series by Jaiyesimi and Antia, there was a relative excess of MS in children with recurrent RF. Higher ASO titres were also documented even in those patients with MS who did not have a recurrence.
Rheumatic heart disease and pregnancy in Nigeria
In the series by Onwuchekwa and Ugwu in Maiduguri, 28.3% of the patients presented in pregnancy. In an early study of HF and pregnancy at the Ahmadu Bello University Teaching Hospital, Kaduna, North Western Nigeria and Abengowe reported that RHD was responsible for 30.6% of cases, 53.3% presented in the postpartum period while the rest antepartum. MR accounted for 66.7% of the valve lesions. In an early study of HF and pregnancy at the Ahmadu Bello University Teaching Hospital, Kaduna, North Western Nigeria, Abengowe reported that RHD was responsible for 30.6% of cases, 53.3% presented in the postpartum period while the rest presented antepartum. Others included pure MS (6.7%), double valve lesions (MS/MR or MS/ AR) (20%), and triple lesions (MS/MR/AR) (6.7%). Majority presented in NYHA functional classes III/IV.
Cole and Adeleye at Ibadan studied 44 pregnancies in 32 Nigerian women between the ages of 16 and 38 years (mean 27 years) with RHD. Majority of the women were gravida three, but were closely followed by the primigravidae. Pure MR was the most common valve lesion encountered. Acute pulmonary edema was common, occurring in 11 patients and which was responsible for 2 of the 3 maternal deaths. Congestive cardiac failure was the second commonest presentation (in 7) and infective endocarditis occurred in 4 patients. The third maternal death was in a woman with mitral valve prosthesis who was also on warfarin. The major precipitating factors for HF include infective endocarditis, AF with uncontrolled ventricular rate, anemia, and chest infection. In the series reported by Abengowe, congestive HF was more common than acute pulmonary edema. The perinatal mortality was 11/1000 and average birth weight was 2.7 kg, but there were five cases of low birth weight babies. At 6 months' postpartum, there was evidence of progression in eight cases. [Figure 4] shows the cardiac complications in the Ibadan series.
Diagnosis of rheumatic heart disease
The diagnosis of RHD in Nigeria has evolved over the past several decades since the early cases were reported. While clinical and autopsy diagnostic tools predominated in the early reports, current reports use mainly echocardiography in making diagnosis thereby improving our knowledge and understanding of the disease.
In [Table 3], the prevalence of RHD in autopsy/morbidity studies is presented, with the prevalence of RHD ranging from 7.5% to 17.1%.
As shown in [Table 2] which represents the burden of RHD in various echocardiography registries in the country, the prevalence of RHD ranges from 2.5 to 38.5. It has to been noted, however, that in many of the studies, there is a mixture of adults and children.,,,
Congestive HF is by far the most common complication in Nigerian children (88%). Others include pulmonary hypertension (45%), bacterial endocarditis (14%), and AF (11%) [Table 6]. Intramural thrombosis and superior vena cava occlusion were reported in 2.5% and 1.3%, respectively, in the Ibadan series.
|Table 6: Spectrum of complications/mode of presentation reported from different centres in Nigeria|
Click here to view
The spectrum of complications in various adult studies in the country is also shown in [Table 6]. Congestive cardiac failure is by far the most common complication. This is the mode of presentation in over 80% of cases in Abeokuta. Pulmonary hypertension is common occurring in 54.2%–72.1% of adult RHD in the country. Others include AF (10.1%–25.8%), infective endocarditis (4.7%–14%), stroke (1.1%–4.2%), intramural thrombosis (2.3%–2.8%), and valvular cardiomyopathy (31.8%, reported in only one study).
About 20% of children with RHD die within 6 years of onset of the illness. About half of the deaths occurred within the 1st year. Most deaths occurred as a result of HF or bacterial endocarditis.,,,
In a reassessment of 25 children with RHD who were followed up for up to 4 years, Jaiyesimi and Antia noted that compared to their initial status, 20% of them had improved, 32% remained about the same while 48% had deteriorated.
The authors went further to prospectively study 48 Nigerian children (22 males and 26 females, aged 3–15 years; mean 8 years) with established RHD to determine the factors that influenced prognosis in a 3-year follow-up period. They reported that at the end of the 3-years, 12 (25%) had improved, 14 (29%) remained the same while 22 (46%) had deteriorated or died.
A poor socioeconomic status, delays in seeking medical care, and recurrence of the RF were associated with poor prognosis, as were the presence of MS, multiple valve lesions, presence of elevated pulmonary pressure, bacterial endocarditis, and pulmonary embolism. Outcome was not affected by age, gender and PR-interval.
The authors concluded that in “developing countries where primary prevention of RF might be vitiated by poverty, ignorance and scarcity of health facilities, the prognosis in childhood RHD can be improved by simple and relatively inexpensive measures like health education, effective SBE prophylaxis and prevention of recurrent ARF. Mitral valvotom, where feasible can improve not only the chances of survival of but also the quality of life in children with disabling mitral stenosis.”
Economic cost of rheumatic heart disease in Nigeria
Chronic RHD is associated with huge financial burden on the families of affected children. It renders a large proportion of children physically and educationally handicapped and therefore deprives the country of potential skilled workforce.
Jaiyesimi assessed the cost of medical care of 20 patients with RHD seen at the UCH, Ibadan over a 1-year period. He observed that despite the fact that majority of the children were from poor homes, the caregiver contributed about 4.4% of their annual income in the care of these patients. In addition, the country spends a substantial amount in their care and that the total costs of treating one patient medically for 12 months could have prevented 4–5 cases of RHD.
Changing face of rheumatic heart disease in Nigeria
In a more recent report of adult patients seen in a tertiary care center over a 9 years period in Oshogbo south west Nigeria, RHD was seen among 11 of the 9,423 patients seen in the medical outpatient clinic giving a hospital-based prevalence of 1.2 per thousand. Similar reports from the southeastern part of the country also showed a low prevalence of RHD pointing to a probability of a declining burden of RHD in Nigeria. But as it is with previous reports, the most common valve affected was mitral (90.9%), followed by the aortic (36.4%), and the tricuspid (18.2%). Mitral and aortic lesions coexisted in 18.2% of the patients. Late presentation was a common phenomenon among the patients seen.
Community screening for rheumatic heart disease in Nigeria
The earliest community based study for RHD in Nigeria was the one reported by Ogunbi et al. in Lagos in 1978 where 12, 755 school children were screened for evidence of RHD. They reported RHD in 11 (7 old and 4 new cases), given a community prevalence of 0.08%. recently, Yilgwan et al. in Jos and Sadoh et al. in Benin used the same clinical screening methods among school children as Ogunbi. Yilgwan et al. found no child with RHD after screening 418 children using cardiac auscultation while Sadoh et al. reported a case of RHD among 1,766 using similar methods. These findings though gladdening may reflect the low sensitivity of the methods used. Echocardiographic screening has been shown to be a more sensitive method for detecting RHD among asymptomatic patients in the community. A community based echo screening for RHD will thus need to be planned as a way to evaluate the true community based prevalence of RHD.
Recently Ekure et al. screened 4107 children (mean age of 11.3 years), 53.7% females in urban and periurban areas of Lagos. They detected 38 children with abnormal echocardiograms, of which 11 (0.27%) showed RHD including two cases of definite RHD giving a prevalence of 2.7/1000 (2.9/1000 in the periurban, 2.4/1000 in the urban area). Echocardiography was reported to detected RHD 10 times better than auscultation (echocardiography 11 (0.27%) vs. auscultation 1 (0.02%); P = 0.003]. The remaining 27 children with abnormal echocardiograms had congenital heart defects (CHD) giving a prevalence of 6.6/1000 for CHD, a yield higher than for RHD.
| Conclusions|| |
RHD still remains a major cardiovascular health problem in Nigeria. There is therefore a need for more recent clinical studies on the contemporary pattern of RHD in Nigeria. In addition, more community-based screening for RHD is needed to determine the true burden of the disease in Nigeria. Finally, primary and secondary preventive measures are needed to help reduce the burden of RHD in Nigeria.
Financial support and sponsorship
Conflicts of interest
There are no conflicts of interest.
| References|| |
Carapetis JR, Steer AC, Mulholland EK, Weber M. The global burden of group A streptococcal diseases. Lancet Infect Dis 2005;5:685-94.
Reményi B, Wilson N, Steer A, Ferreira B, Kado J, Kumar K, et al
. World Heart Federation criteria for echocardiographic diagnosis of rheumatic heart disease--an evidence-based guideline. Nat Rev Cardiol 2012;9:297-309.
World Health Organization. Rheumatic Fever and Rheumatic Heart Disease. Report of a WHO Study Group. World Health Organization Technical Report Series. World Health Organization; Vol. 764. 1988. p. 1-58.
Nordet P, Lopez R, Dueñas A, Sarmiento L. Prevention and control of rheumatic fever and rheumatic heart disease: the Cuban experience (1986-1996-2002). Cardiovasc J Afr 2008;19:135-40.
Onwuchekwa AC, Asekomeh GE. Pattern of heart failure in a Nigerian teaching hospital. Vasc Health Risk Manag 2009;5:745-50.
Ojji DB, Alfa J, Ajayi SO, Mamven MH, Falase AO. Pattern of heart failure in Abuja, Nigeria: an echocardiographic study. Cardiovasc J Afr 2009;20:349-52.
Karaye KM, Sani MU. Factors associated with poor prognosis among patients admitted with heart failure in a Nigerian tertiary medical centre: a cross-sectional study. BMC Cardiovasc Disord 2008;8:16.
Ansa VO, Ekott JU, Bassey EO. Profile and outcome of cardiovascular admissions at the University of Uyo Teaching Hospital, Uyo--a five year review. Niger J Clin Pract 2008;11:22-4.
Antony KK. Pattern of cardiac failure in Northern Savanna Nigeria. Trop Geogr Med 1980;32:118-25.
Abengowe CU. Cardiovascular disease in Northern Nigeria. Trop Geogr Med 1979;31:553-60.
Ladipo GO, Froude JR, Parry EH. Pattern of heart disease in adults of the Nigerian Savanna: A prospective clinical study. Afr J Med Med Sci 1977;6:185-92.
Carlisle R, Ogunlesi TO. Prospective study of adult cases presenting at the Cardiac Unit, University College Hospital, Ibadan 1968 and 1969. Afr J Med Sci 1972;3:13-25.
Beet EA. Rheumatic heart disease in Northern Nigeria. Trans R Soc Trop Med Hyg 1956;50:587-92.
Ogah OS, Stewart S, Falase AO, Akinyemi JO, Adegbite GD, Alabi AA, et al
. Contemporary profile of acute heart failure in Southern Nigeria: Data from the Abeokuta Heart Failure Clinical Registry. JACC Heart Fail 2014;2:250-9.
Oguanobi NI, Ejim EC, Onwubere BJ, Ike SO, Anisiuba BC, Ikeh VO, et al
. Pattern of cardiovascular disease amongst medical admissions in a regional teaching hospital in Southeastern Nigeria. Nig J Cardiol 2013;10:77-80. [Full text]
Ojji D, Stewart S, Ajayi S, Manmak M, Sliwa K. A predominance of hypertensive heart failure in the Abuja Heart Study cohort of urban Nigerians: A prospective clinical registry of 1515 de novo
cases. Eur J Heart Fail 2013;15:835-42.
Ogah OS, Adebiyi AA, Oladapo OO, Adekunle AN, Oyebowale OM, Falase AO, et al
., editors. The changing patterns of heart disease in Nigeria: Data from the Ibadan outpatient cardiac Registry. Lippincott Williams and Wilkins; Philadelphia, USA: 2012.
Laabes EP, Thacher TD, Okeahialam BN. Risk factors for heart failure in adult Nigerians. Acta Cardiol 2008;63:437-43.
Familoni OB, Olunuga TO, Olufemi BW. A clinical study of pattern and factors affecting outcome in Nigerian patients with advanced heart failure. Cardiovasc J Afr 2007;18:308-11.
Adewuya AO, Ola BA, Ajayi OE, Oyedeji AO, Balogun MO, Mosaku SK. Prevalence and correlates of major depressive disorder in Nigerian outpatients with heart failure. Psychosomatics 2006;47:479-85.
Ladipo GO. Cardiac failure at Ahmadu Bello University Hospital, Zaria. Niger Med J 1978;8:96-9.
Uzodike VO. The pattern of heart disease in Enugu, Nigeria. Nig Med J 1975;7:315-9.
Ogunmekan GO. Analysis of medical admissions to Adeoyo state hospital, Ibadan, 1969. Niger Med J 1973;3:5-12.
Oviasu VO. The pattern of heart disease in Benin, Nigeria. Nig Med J 1973;3:192-5.
Okuwobi BO. Pattern of heart failure at Lagos university teaching hospital. West Afr Med J Niger Pract 1967;16:198-203.
Lauckner JR, Rankin AM, Adi FC. Analysis of medical admissions to University College Hospital, Ibadan – 1958. West Afr Med J 1961;10:3-2.
Nwokolo C. Endomyocardial fibrosis and other obscure cardiopathies in eastern Nigeria. West Afr Med J 1955;4:103-16.
Ansa VO, Odigwe CO, Agbulu RO, Odudu-Umoh I, Uhegbu V, Ekripko U. The clinical utility of echocardiography as a cardiological diagnostic tool in poor resource settings. Niger J Clin Pract 2013;16:82-5.
] [Full text]
James OO, Efosa JD, Romokeme AM, Zuobemi A, Sotonye DM. Dominance of hypertensive heart disease in a tertiary hospital in southern Nigeria: an echocardiographic study. Ethn Dis 2012;22:136-9.
Ogah OS, Adegbite GD, Akinyemi RO, Adesina JO, Alabi AA, Udofia OI, et al
. Spectrum of heart diseases in a new cardiac service in Nigeria: an echocardiographic study of 1441 subjects in Abeokuta. BMC Res Notes 2008;1:98.
Sani MU, Karaye KM, Ibrahim DA. Cardiac morbidity in subjects referred for echocardiographic assessment at a tertiary medical institution in the Nigerian savanna zone. Afr J Med Med Sci 2007;36:141-7.
Agomuoh DI, Akpa MR, Alasia DD. Echocardiography in the university of Port Harcourt Teaching Hospital: April 2000 to March 2003. Niger J Med 2006;15:132-6.
Ike SO. Echocardiographic analysis of valvular heart diseases over one decade in Nigeria. Trans R Soc Trop Med Hyg 2008;102:1214-8.
Adebayo RA, Akinwusi PO, Balogun MO, Akintomide AO, Adeyeye VO, Abiodun OO, et al
. Two-dimensional and Doppler echocardiographic evaluation of patients presenting at Obafemi Awolowo university teaching hospitals complex, Ile-Ife, Nigeria: A prospective study of 2501 subjects. Int J Gen Med 2013;6:541-4.
Talle MA, Anjorin CO, Buba F, Bakki B. Spectrum of cardiovascular diseases diagnosed using transthoracic echocardiography: Perspectives from a tertiary hospital in North-Eastern Nigeria. Nig J Cardiol 2016;13:39-45. [Full text]
Saidu H, Sani MU, Mijinyawa MS, Yakasai AM. Echocardiographic pattern of heart diseases in a North - Western Nigerian tertiary health institution. Niger J Basic Clin Sci 2015;12:39-44. [Full text]
Uwanuruochi K, Offia E, Ukpabi OJ, Chuku A, Ogah OS. Initial experience with echocardiography at the federal medical centre, Umuahia, Nigeria. Niger J Cardiol 2015;12:13.
Ejim EC, Ubani-Ukoma CB, Nwaneli UC, Onwubere BJ. Common echocardiographic abnormalities in Nigerians of different age groups. Niger J Clin Pract 2013;16:360-4.
] [Full text]
Ajuluchukwu J, Ekure E. Echocardiographic features of rheumatic heart disease in Lagos. Mary Slessor J Med 2010;10:10-7.
Kolo PM, Sanya EO, Omotosho AB, Chijoke A, Dada SA. The role of echocardiography in the management of stroke. West Afr J Med 2010;29:239-43.
Aje A, Adebiyi AA, Oladapo OO, Ogah OS, Dada A, Ojji DB, et al
. Audit of Echocardiographic Services at the University College Hospital Ibadan. Niger J Med 2009;18:32-4.
Ukoh VA, Omuemu C. Spectrum of heart diseases in adult Nigerians: An echocardiographic study. Nig J Cardiol 2005;2:24-7.
Balogun M, Urhoghide G, Ukoh V, Adebayo R. A preliminary audit of two dimensional and Doppler echocardiographic service in a Nigerian tertiary private hospital. Nig J Med. 1999;8:139-41.
Adetuyibi A, Akisanya JB, Onadeko BO. Analysis of the causes of death on the medical wards of the University College Hospital, Ibadan over a 14-year period (1960-1973). Trans R Soc Trop Med Hyg 1976;70:466-73.
Sani MU, Mohammed AZ, Bapp A, Borodo MM. A three-year review of mortality patterns in the medical wards of Aminu Kano Teaching Hospital, Kano, Nigeria. Niger Postgrad Med J 2007;14:347-51.
Olubuyide IO, Solanke TF. The causes of death in an elderly African population. J Trop Med Hyg 1990;93:270-4.
Junaid TA. Mortality in middle-aged Nigerians: an autopsy study. Trop Geogr Med 1979;31:389-94. autopsy study. Trop Geogr Med 1979;31:389-94.
Adeolu AA, Arowolo OA, Alatise OI, Osasan SA, Bisiriyu LA, Omoniyi EO, et al
. Pattern of death in a Nigerian teaching hospital; 3-decade analysis. Afr Health Sci 2010;10:266-72. hospital; 3-decade analysis. African health sciences. 2010;10 (3).
Chijioke A, Kolo P. P. Mortality pattern at the adult medical wards of a teaching hospital in sub-Saharan Africa. Int J Trop Med. 2009;4:27-31.
Bode-Thomas F, Ige OO, Yilgwan C. Childhood acquired heart diseases in Jos, north central Nigeria. Niger Med J 2013;54:51-8.
] [Full text]
Akinwusi PO, Peter JO, Oyedeji AT, Odeyemi AO. The new face of rheumatic heart disease in South West Nigeria. Int J Gen Med 2013;6:375-81.
Essien IO, Onwubere BJ, Anisiuba BC, Ejim EC, Andy JJ, Ike SO. One year echocardiographic study of rheumatic heart disease at Enugu, Nigeria. Niger Postgrad Med J 2008;15:175-8.
Sani MU, Karaye KM, Borodo MM. Prevalence and pattern of rheumatic heart disease in the Nigerian savannah: An echocardiographic study. Cardiovasc J Afr 2007;18:295-9.
Onwuchekwa AC, Ugwu EC. Pattern of rheumatic heart disease in adults in Maiduguri – North East Nigeria. Trop Doct 1996;26:67-9.
Ogunbi O, Fadahunsi HO, Ahmed I, Animashaun A, Daniel SO, Onuoha DU, et al
. An epidemiological study of rheumatic fever and rheumatic heart disease in Lagos. J Epidemiol Community Health 1978;32:68-71.
Fadahunsi HO, Coker AO, Usoro PD. Rheumatic heart disease in Nigerian children: Clinical and preventive aspects. Ann Trop Paediatr 1987;7:54-8.
Okoroma EO, Ihenacho IN, Anyanwu CH. Rheumatic fever in Nigerian children. A prospective study of 66 patients. Am J Dis Child 1981;135:236-8.
Jaiyesimi F, Antia AU. Childhood rheumatic heart disease in Nigeria. Trop Geogr Med 1981;33:8-13.
Cole TO. Rheumatic fever and rheumatic heart disease in the tropics with particular reference to Nigeria. Niger Med J 1976;6:123-6.
Animasahun BA, Madise Wobo AD, Itiola AY, Adekunle MO, Kusimo OY, Thomas FB. The burden of rheumatic heart disease among children in Lagos: How are we fairing? Pan Afr Med J 2018;29:150.
Okpara CI, Edward ES. Echocardiographic pattern of rheumatic heart disease In Makurdi Nigeria. OSR Journal of Dental and Medical Sciences 2017;16:14-20.
Okoromah CA, Ekure EN, Ojo OO, Animasahun BA, Bastos MI. Structural heart disease in children in Lagos: profile, problems and prospects. Niger Postgrad Med J 2008;15:82-8.
Wilson SE, Chinyere UC, Queennette D. Childhood acquired heart disease in Nigeria: An echocardiographic study from three centres. Afr Health Sci 2014;14:609-16.
Akpa M, Dodiyi-S DD, Agada Z, Odia O. Rheumatic heart disease in Port Harcourt, Nigeria: Clinical, demographic and echocardiographic features. Port Harcourt Med J 2012;6:339-43.
Sani UM, Ahmed H, Jiya NM. Pattern of acquired heart diseases among children seen in Sokoto, North-Western Nigeria. Niger J Clin Pract 2015;18:718-25.
] [Full text]
Ogah OS, Adegbite GD, Udoh SB, Ogbodo EI, Ogah FA, Adesemowo A, et al
. Chronic rheumatic heart disease in Abeokuta, Nigeria: Data from the Abeokuta heart disease registry. Nig J Cardiol 2014;11:98-103. [Full text]
Danbauchi S, Alhassan M, David S, Wammanda R, Oyati I. Spectrum of rheumatic heart disease in Zaria, Northern Nigeria. Annals of African Medicine 2004;3:17-21.
Cole TO. Pattern of rheumatic heart disease in Nigerians. Trop Cardiol 1980;6:69.
Cole TO. Rheumatic fever; A 10-year review of cases admitted to University College Hospital Ibadan (Editorial). West Afr Med J 1978;24:45.
Antia AU, Effiong CE, Dawodu AH. The pattern of acquired heart disease in Nigerian children. Afr J Med Sci 1972;3:1-2.
Strasser T, Dondog N, El Kholy A, Gharagozloo R, Kalbian VV, Ogunbi O, et al
. The community control of rheumatic fever and rheumatic heart disease: Report of a WHO international cooperative project. Bull World Health Organ 1981;59:285-94.
Cole TO. Problems of rheumatic fever in Nigerians. Trop Cardiol 1980;6:181-7.
Antia AU, Reddy S. Rheumatic heart disease in children in developing countries. Ghana Med J 1971;10:9-13.
Donnison C. Blood pressure in the African natives: Its bearing upon aetiology of hyperplasia and arteriosclerosis. Lancet 1929;1:6-7.
Rogers L. Life insurance in the tropics. Brit Med J 1928;1:219.
Clarke JT. The nature of rheumatic poisoning. J Trop Med 1932;35:55.
Cole TO. Streptococal infection in relation to rheumatic fever and rheumatic heart disease. Cardiovasc Proj 1972;1:1959.
Vakil RJ. A statistical study of 1281 cases of congestive cardiac failure or myocardial insufficiency in India. Indian Physician 1949;8:281-9.
Padmavati S. Epidemiology of cardiovascular disease in India. I. Rheumatic heart disease. Circulation 1962;25:703-10.
Padmavati S. Epidemiology of cardiovascular disease in India. II. Ischemic heart disease. Circulation 1962;25:711-7.
Muir CS. Rheumatic heart disease in Singapore; a survey of the morbid anatomical features. Trans R Soc Trop Med Hyg 1958;52:446-53.
Baldachin BJ. Cardiac disease in the African in Matabeleland. A survey based on records of 150 patients. East Afr Med J 1959;36:542-8.
Shaper AG, Williams AW. Cardiovascular disorders at an African hospital in Uganda. Trans R Soc Trop Med Hyg 1960;54:12-32.
Mayosi BM. Contemporary trends in the epidemiology and management of cardiomyopathy and pericarditis in sub-Saharan Africa. Heart 2007;93:1176-83.
Edington GM. Cardiovascular disease as a cause of death in the Gold Coast African. Trans R Soc Trop Med Hyg 1954;48:419-25.
Okuwobi BO. Pattern of heart diseases in Lagos. East Afr Med J 1968;45:122-7.
Cole TO, Adeleye JA. Rheumatic heart disease and pregnancy in Nigerian women. Clin Cardiol 1982;5:280-5.
Jaiyesimi F, Antia AU. Prognostic factors in childhood rheumatic disease. Trop Geogr Med 1981;33:14-38.
Cole TO, Oluwasanmi JO, Alabi GO, Falase AO, Carlisle R. Keloid formation and heart disease. Cardiovasc Proj 1972;2:191.
Parry EH, Ikeme AC. Cardiovascular Disease in Nigeria. Ibadan: University Press; 1966.
Oluwasanmi JO. Keloids in Ibadan. Trop Geogr Med 1974;26:231-41.
Oluwasanmi JO. Keloids in the African. Clin Plast Surg 1974;1:179-95.
Abengowe CU, Das CK, Siddique AK. Cardiac failure in pregnant Northern Nigerian women. Int J Gynaecol Obstet 1980;17:467-70.
Ifere OA, Masokano KA. Infective endocarditis in children in the Guinea savannah of Nigeria. Ann Trop Paediatr 1991;11:233-40.
Falase AO, Jaiyesimi F, Iyun AO, Attah EB. Infective endocarditis-experience in Nigeria. Trop Geogr Med 1976;28:9-15.
Omokhodion SI, Akang EE, Pindiga HU, Abowehyere J, Liman AS. The changing pattern of childhood infective endocarditis in Ibadan: A report of neonatal candidal endocarditis and a review of 33 years of autopsy records. Trop Cardiol 1997;23:25-31.
Jaiyesimi F. Chronic rheumatic heart disease in childhood: Its cost and economic complications. Trop Cardiol 1982;8:55-8.
Yilgwan CS, Ige OO, Bode-Thomas F. Clinical screening for heart disease in apparently healthy Nigerian school children. Nig J Cardiol 2014;11:74-9. [Full text]
Sadoh WE, Omuemu VO, Israel-aina YT. Prevalence of rheumatic heart disease among primary school pupils in mid-Western Nigeria. East Afr Med J 2013;90:28-32.
Ekure EN, Amadi C, Sokunbi O, Kalu N, Olusegun-Joseph A, Kushimo O, et al
. Echocardiographic screening of 4107 Nigerian school children for rheumatic heart disease. Trop Med Int Health 2019;24:757-65.
Oyedeji AT, Akintunde AA, Owojori OO, Peter JO. Spectrum of Echocardiography Abnormalities among 168 Consecutive Referrals to an Urban Private Hospital in South-Western Nigeria. Clinical Medicine Insights: Cardiology. 2014 Jan;8:CMC-S14320.
[Figure 1], [Figure 2], [Figure 3], [Figure 4]
[Table 1], [Table 2], [Table 3], [Table 4], [Table 5], [Table 6]