Nigerian Journal of Cardiology

: 2016  |  Volume : 13  |  Issue : 1  |  Page : 39--45

Spectrum of cardiovascular diseases diagnosed using transthoracic echocardiography: Perspectives from a tertiary hospital in North-Eastern Nigeria

Mohammed Abdullahi Talle, Charles Oladele Anjorin, Faruk Buba, Bukar Bakki 
 Department of Internal Medicine, Division of Cardiology, University of Maiduguri Teaching Hospital, PMB 1414, Maiduguri, Nigeria

Correspondence Address:
Mohammed Abdullahi Talle
Department of Internal Medicine, Division of Cardiology, University of Maiduguri Teaching Hospital, PMB 1414, Maiduguri


Background: The advent of echocardiography has tremendously improved the diagnosis of cardiovascular diseases. We present a review of cardiovascular disorders diagnosed using transthoracic echocardiography over 3 years. Materials and Methods: Echocardiographic data of patients from January 2011 to December 2013 were retrieved. All subjects had standard transthoracic echocardiography including Doppler modalities where appropriate. Descriptive statistics was used in assessing the occurrence of the different cardiac disorders. Results: One thousand three hundred and two echocardiograms were considered, out of which 1224 (94%) comprising 591 (48.3%) males and 633 (51.7%) females were analyzed. Ages ranged from 4 days to 105 years with a mode of 60 years and a mean of 39.62 ± 20.58 years. The most common indications were hypertensive heart disease (HHD) (28.2%) and congestive cardiac failure (23.4%). HHD was the most common diagnosis (25.1%) followed by cardiomyopathies (23.9%). Idiopathic dilated (29.3%) and peripartum cardiomyopathy (23.1%) were the most common cardiomyopathies. Valvular heart diseases (VHD) were diagnosed in 14.9%, with rheumatic (60.4%), and degenerative (36.4%) being dominant. Congenital heart disease was diagnosed in 7.2%, with 70.5% of the cases in those ≤14 years. Ischemic heart disease was diagnosed in 6.6%. Pericardial diseases were found in 3.2%, while cor pulmonale was documented in 0.8%. Atrial myxoma dissection of the ascending aorta, athlete's heart, and amniotic fluid embolism were each observed in <1%. A normal echocardiogram was reported in 13.3%. Conclusion: The most common echocardiographic diagnoses in our center are HHD, cardiomyopathies, and VHD. Congenital and ischemic heart diseases are also prevalent.

How to cite this article:
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

How to cite this URL:
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 [serial online] 2016 [cited 2021 May 15 ];13:39-45
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The advent of echocardiography has significantly revolutionized the evaluation and management of patients with cardiovascular diseases.[1] An invasive procedure involving cardiac catheterization for assessment of cardiac disorders, which had hitherto, been the modality of choice has been largely replaced by echocardiography with a comparable level of accuracy.[2] Echocardiography has the unparalleled advantage of being a noninvasive and low-cost procedure with the ability to promptly provide quantitative information about cardiac structure and function.[3]

Despite the increase, in the number of centers providing echocardiography services across the country, there remains a significant proportion of the populace without access to the echocardiography. This is notwithstanding the fact that there is growing scourge of cardiovascular diseases. This trend is similar to what obtains in other developing countries of Sub-Saharan Africa.

Reports on the spectrum of cardiac diseases diagnosed on echocardiogram from centers providing echocardiography consistently reported hypertensive heart disease (HHD) followed by valvular heart disease (VHD) and cardiomyopathy as the most common diagnoses.[4],[5],[6],[7] The reports from Enugu in South-eastern Nigeria starkly differed where VHD was strikingly the most common diagnosis, surpassing HHD by almost 50%.[8] Studies from the neighboring country of Cameroon reported HHD, cardiomyopathy, and VHD as the most frequent echocardiographic diagnosis among patients presenting with heart failure.[9]

Although the epidemiology of cardiovascular diseases may be similar across the different regions of Nigeria, differences in cultural practices, as well as differences in environmental factors, may impact on the pattern of cardiac disorders. We sought to review retrospectively the spectrum of cardiac diseases diagnosed by echocardiography at a tertiary hospital in North-eastern Nigeria over a 3 years period. In addition to providing valuable information for policy formulation, this will provide additional information to the existing pool of data on the practice of echocardiography in the country.

 Materials and Methods

We studied the echocardiographic data of patients that underwent transthoracic echocardiography at our hospital over a 3 years period from January 2011 to December 2013. The hospital is a 500-bed capacity tertiary hospital that serves as a referral center, catering for the northeast sub-region. Patients are also referred for echocardiography from the neighboring countries of Cameroon and Chad. Echocardiography is routinely done twice a week and the on-demand basis for emergencies and in-patients.

The echocardiographic procedures were performed with MyLab 50CV (Esaote) and Siemens Acuson X300 (Siemens). Echocardiograms were obtained using M-mode, 2D-mode, color flow, and Doppler modalities from the standard transthoracic windows (as well as subcostal and suprasternal windows), adhering to the ASE guideline.[10] Where necessary, off-axis views were obtained to optimize visualization of intra-cardiac masses. Imaging was performed by trained cardiologists with expertise in echocardiography. Two of the three cardiologists at the center were present during the period being reported. All images are routinely copied from the hard drive of the ultrasound machine to a CD/DVD for storage.

Diagnoses of the various cardiac conditions were made based on existing standard guidelines. HHD was diagnosed in hypertensive patients in the presence of concentric/eccentric left ventricular hypertrophy or concentric left ventricular remodeling, left atrial dilatation and/or systolic, and/or diastolic left ventricular dysfunction.[11] Degenerative VHD and other nonrheumatic valvular lesions were evaluated in accordance with the European Society of Cardiology guidelines on management of VHDs while rheumatic heart disease (RHD) was diagnosed following the World Heart Federation criteria for the echocardiographic diagnosis of RHD.[12],[13] Because of lack of cardiac biomarkers in our center, the World Health Organization (WHO) category B definition and diagnostic criteria of myocardial infarction was used.[14] Myocardial infarction was diagnosed in the presence of symptoms of ischemia and development of unequivocal pathological Q waves. Similarly, prior myocardial infarction was diagnosed in the presence of loss of viable myocardium, that is, thinned and fails to contract (regional wall motion abnormalities) or pathologic Q waves on electrocardiography (ECG) with/without symptoms.[14] Peripartum cardiomyopathy (PPCM) was defined as an idiopathic cardiomyopathy presenting with heart failure secondary to left ventricular systolic dysfunction (ejection fraction <45%) toward the end of pregnancy or in the months following delivery in the absence of other identifiable cause of heart failure.[15] We used the presentation in the last month of pregnancy or within 5 months of postpartum period. Heart failure was diagnosed in the presence of symptoms and signs typical of heart failure, and echocardiographic evidence of structural and/or functional abnormality of the heart at rest.[16] Hypertrophic cardiomyopathy (HCM) was diagnosed in the presence of unexplained maximal wall thickness of >15 mm in any myocardial segment, or septal/posterior wall thickness ratio of >1.3 in normotensive patients, or septal/posterior wall thickness ratio >1.5 in hypertensive patients.[17],[18]

Cases of pericardial diseases included only those with massive effusion and/or constriction, tamponade physiology, and metastases. Constrictive pericarditis was differentiated from restrictive heart disease using tissue Doppler; where suspected, congenital heart disease (CHD) was systematically assessed for using the sequential segmental approach (European approach on account of the promoters of the original concept).[19] The data were analyzed using SPSS version 16.0 Chicago, IL, USA. Descriptive statistics was used in describing the different spectrum of echocardiographic diagnosis. Approval was granted by the Research and Ethics Committee as part of the Heart Failure Registry.


One thousand three hundred and two transthoracic echocardiograms performed over the 3 years period were available for review. Seventy-eight (6.0%) were excluded due to poor image quality, inconclusive study, and incomplete data storage. The remaining 1224 were made of 591 (48.3%) males and 633 (51.7%) females (male to female ratio of 1:1.1). Their ages range from 4 days to 105 years with a mode of 60 years. The mean age was 39.62 ± 20.58 years. One hundred and thirteen (9.2%) were aged 14 years and below.

Indications for echocardiography are illustrated in [Table 1]. The most common indication was HHD (28.2%) followed by congestive heart failure of various etiologies (23.4%). Abnormal ECG findings for which echocardiograms were requested included left ventricular hypertrophy, bundle branch blocks, atrial fibrillation, complete heart blocks, advanced heart block, and other forms of tachyarrhythmia. The category labeled “others” includes a request for preoperative assessment, routine medical check-up, and unspecified indications. Some of the echocardiograms obtained are illustrated in [Figure 1].{Table 1}{Figure 1}

The various diagnoses based on echocardiograms are illustrated in [Table 2] for patients 15 years and older, and [Table 3] for those 14 years and below. The most common diagnosis in those 15 years and older was HHD, observed in 307 (27.6%) followed by the various forms of cardiomyopathies in 287 (25.8%). Idiopathic dilated cardiomyopathy (DCM, 59.2%) and PPCM (24.7%) were the most common forms of cardiomyopathies. There were 8 (2.8%) cases of HCM. The most common diagnoses in 14 years old and below were CHDs (54.9%) and RHD (22.1%).{Table 2}{Table 3}

There were 154 (13.9%) cases of VHD of various etiologies among those 15 years and older, the most common being RHD (52.6%) followed by degenerative VHD (40.9%). Mitral valve prolapse (MVP) was diagnosed in 3 (1.9%) while posttraumatic mitral regurgitation (MR) was diagnosed in 2 (1.3%). The frequencies of the different forms of RHD in those 15 years and older are depicted in [Figure 2], while an echocardiographic illustration of rheumatic mitral and aortic valve diseases (AVDs) is illustrated in [Figure 1]c and [Figure 1]d. Five (3.2%) of the 15 years and older had prosthetic valves (all mechanical), whereas 3 (1.9%) had valve repair (two mitral and one tricuspid). Vegetation was documented in 6 (7.4%) of those 15 years and above, and 2 (8.0%) of the 14 years and younger with RHD. Two (28.6%) of all MVP had vegetation.{Figure 2}

CHD was diagnosed in 26 (2.3%) of those 15 years and above, and 62 (54.9%) of the 14 years and younger, with the most prevalent being ventricular septal defect (VSD) in 5 (19.2%) and 18 (29.0%), respectively. Tetralogy of Fallot (TOF) was diagnosed in 6 (30.8%) of those 15 years and older, and 8 (12.9%) of the 14 years and younger age group. Ebstein's anomaly was diagnosed in 5 (19.2%) of the 15 years and older patients. The different forms of CHDs in those 15 years and above are illustrated in [Figure 3].{Figure 3}

Ischemic heart disease was diagnosed in 81 (7.3%), predominantly in males (74.1%) while isolated diastolic dysfunction in the absence of hypertension was observed in 55 (5.0%). There were 32 (2.9%) cases of pericardial diseases in patients 15 years and older that included massive pericardial effusion, cardiac tamponade, constrictive pericarditis, and metastases to the pericardium. Six (5.3%) cases of massive pericardial effusion were recorded in patients 14 years and below. There were 6 (18.8%) and 2 (33.3%) cases of tuberculous (TB) pericarditis with fibrin strands [Figure 1]a among the 15 years and above; and the younger age group, respectively. The pericardial constriction was diagnosed in 7 (21.9%) of those 15 years and above. Pericardial effusion with tamponade physiology was documented in 5 (15.6%) of those 15 years and older including two cases of posttraumatic hemorrhagic pericardial effusion. Two (33.3%) of those with pericardial effusion among the 14 years and below had tamponade physiology. One (3.1%) case of metastases from hepatocellular carcinoma to the pericardium was diagnosed in a 56-year-old male patient.

Cor pulmonale was diagnosed in 10 (0.9%) of patients 15 years and older, whereas atrial myxoma was found in 5 (0.5%). Similarly, dissection of the ascending aorta in association with aneurysm was found in 2 (0.2%), while athlete heart and amniotic fluid embolism were each diagnosed in 1 (0.1%) of the same age group. Intra-cardiac thrombus was observed in 87 (7.1%) of all age groups with 84 (96.5%) involving the left ventricle.


We report the different echocardiographic diagnoses for cardiovascular disease in a major tertiary health center in North-eastern Nigeria. To our knowledge, this is the first report on the spectrum of cardiovascular diseases diagnosed using echocardiography from the region.

The most common indication for requesting echocardiography in our center was HHD followed by congestive cardiac failure and abnormal ECG. This is similar to what was reported in other centers across the country.[4],[5],[6],[7] The appropriateness or otherwise of the different indications found in our center is difficult to judge, given the heterogeneous nature of the source of referrals for echocardiography. We had more females than males, a finding that differs from other centers.[4],[5],[6] This difference is driven by the higher prevalence of PPCM in our center.

The most prevalent echocardiographic diagnosis among the adults was HHD, a trend that is uniformly reported across the centers offering echocardiography in Nigeria and some other African countries.[4],[5],[6],[7],[9],[20] Many of the centers reported higher prevalence than the 27.6% recorded in our center. This may partly be explained by the disproportionately larger number of hypertensives referred for echocardiography in those centers. The preponderance of HHD is not surprising, given that hypertension is the leading cardiovascular disease risk, resulting in 13% of global death,[21] and the most prevalent cardiovascular disease in Sub-Saharan Africa.[22],[23] Developing countries, Sub-Saharan Africa inclusive, bear two-third of the global burden of hypertension.[24] With the projected increase in the number of adults with hypertension rising to 1.56 billion by the year 2025,[25] a concerted effort is imperative if the menace is to be curtailed. CHDs predominated in those 14 years, and younger followed by RHD, a pattern that reflects earlier reports on pediatric echocardiographic diagnoses.[26],[27]

The various form of cardiomyopathies constituted the second most prevalent echocardiographic diagnosis in adults. The high prevalence of PPCM contrasted with the much lower prevalence in other centers.[4],[5] PPCM constituted the most common etiology among women admitted with heart failure in our center (unpublished data). We had previously reported the high burden of PPCM and its role in the etiology of sudden cardiac death and left ventricular thrombus in our center.[28],[29] Our finding of a prevalence of 2.8% (of all cardiomyopathies) for HCM is higher than what was reported in Abeokuta,[4] but in keeping with what was reported in other centers.[7],[30] A diagnosis of HIV-associated DCM was made in 6.3% of all cardiomyopathies. This might have under-represented the true prevalence since data on HIV-status was not available for all cases of DCM. A rare case of hypothyroid DCM was found in 1 (0.3%) patient that presented with florid features of hypothyroidism. Cases of DCM from hypothyroidism are mostly limited to case reports.[31]

VHDs of varying etiology constituted the third most common diagnosis, with a prevalence of 13.9% in patients 15 years and older. The dominant etiology was RHD, diagnosed in 52.6% of all VHD, a finding similarly reported from other centers.[4],[5],[6],[7] Our report of mixed mitral and AVD [Table 2], [Figure 1]c, [Figure 1]d, and [Figure 2] being the dominant form followed by MR, as well as the preponderance of women, is in keeping with the report of the REMEDY study.[32] Degenerative VHD, accounted for 40.9% of all cases of VHD and was more common in males, with the dominant pattern being aortic and mitral valve diseases. With the increasing prevalence of hypertension and diabetes (two important risk factors for degenerative VHD) in the population,[33] the burden of degenerative VHD is likely to go up in the near future. Despite the high burden of VHD in our population, there were only 5 (3.2%) prosthetic valves, and three cases of valve repairs, all in the adult patients. This reflects the nonexistent cardiac surgery services in our center. Patients requiring intervention are usually referred to other African or Asian countries to access the services, the majority of whom cannot afford. With many centers beginning to offer such services in many parts of Nigeria, there is the likelihood of having an increased access to intervention by patients.

Our diagnosis of CHD in 7.2% of all subjects is similar to what was reported in Ilorin and by Ukoh and Omuemu.[6],[34] Our finding of VSD (25.0%) being the dominant type of CHD followed by TOF (15.9%) is similar to what was reported by Sani et al., in North-western Nigeria.[35] However, we found a higher prevalence of 30.8% among those 15 years and above compared to 11.4% reported in Kano. We also found an equal proportion of atrial septal defect (ASD) and atrio-VSD (AVSD), (12.5% each). One of the patients with ASVD had Ellis-Van Creveld syndrome. Six (6.8%) patients (three cases of AVSD, one case of ASD, and two cases of Ebstein's anomaly) had Eisenmenger complex. All cases of Ebstein's anomaly in our series were found in adults. Although considered to be rare in blacks, we found cases of coarctation of the aorta and congenital aortic stenosis.[36] The findings of 70.5% cases of CHD in those 14 years and younger reflected the pattern of diagnosis in the other centers across the country.

Our finding of a prevalence of 7.3% for ischemic heart disease (IHD) among those 15 years and older is about the highest in the series of published data on echocardiographic diagnosis across the various centers.[4],[5],[6],[7],[8],[20] Though previously considered uncommon, the prevalence of IHD has been on the increase in Nigeria.[37] We previously reported IHD to be the leading cause of sudden cardiac death and the second most common diagnosis associated with left ventricular thrombus in our center.[28],[29] A high index of suspicion in susceptible individuals, especially those with atypical presentation, could improve the diagnostic yield for IHD. Echocardiography plays a significant role in the evaluation of myocardial ischemia/infarction in patients presenting with chest pain, with an appropriate use score of “A (9),” as echocardiographic abnormalities occur earlier than ECG changes along the ischemic cascade of IHD.[38],[39]

Pericardial disease (massive effusion, tamponade physiology, constriction, and metastases) was reported in 3.2% of all age groups. Comparison with other centers is rather difficult since our analysis did not include cases of mild and moderate pericardial effusion without cardiac tamponade. Although difficult to establish with certainty on the basis of echocardiography alone, patients with TB pericardial effusion (21.1%) had effusive constrictive pericarditis [Figure 1]a, judged by the persistence of dilated inferior vena cava with loss of inspiratory collapse despite adequate pericardiocentesis.[40] Primary liver cell carcinoma is one of the malignancies with the propensity of metastasis to the pericardium.[41] We found 1 (0.1%) case of metastasis to the pericardium in a patient with hepatoma, a finding consistent with reports in the literature.[42] However, tumors with the highest propensity of metastasis to the heart include melanomas, lymphomas, cancers of the breast, thyroid, and lungs.[42]

Our finding of 0.9% for cor pulmonale among those 15 years and above is lower than that reported from most other centers.[4],[5],[6] This might be a result of the higher rates of pulmonary diseases than what is prevalent in our population. Our findings of aortic dissection on transthoracic echocardiography [Figure 1]b, as well as athlete's heart, and amniotic fluid embolism have not been reported from other centers in the country. Although we are reporting a similar rate for atrial myxoma, the rate of intra-cardiac thrombus in our series surpasses that reported by most of the centers.[4],[5],[6],[7],[8]


The spectrum of cardiovascular disorders diagnosed on echocardiography in our hospital is largely similar to what obtains in other centers, with the notable exception of higher prevalence rate for IHD, PPCM, and cardiac masses. The availability of echocardiography in our center has greatly improved our ability to diagnose a wide range of cardiovascular disorders. This, however, has not been matched with the availability of the required treatment options for a large number of the cases diagnosed, a scenario that is prevalent in most centers in the country. With the projected escalation in rates of cardiovascular disease in developing countries, there is the need to improve on facilities and manpower development to carter for the increasing needs of cardiovascular care.


Our report has a number of limitations inherent in retrospective analysis. The analysis on age fell short by missing an entry in 62 subjects where age was entered as either adult, child, or infant. We could not sensibly compare echocardiographic diagnoses with indications as documented in the request because of their heterogeneous and in some cases incongruous, nature. Our report on cardiac (especially atrial) thrombus and vegetation might be short of the actual occurrence given that a complementary transesophageal echocardiography may be required. Our diagnosis of myocardial infarction was based on the WHO category B definition and diagnosis of myocardial infarction for lack of cardiac enzymes and coronary angiography or computed tomography angiography.


Support of all the staff of Echocardiography Lab, as well as Medical Records Department, is highly appreciated.

Financial support and sponsorship


Conflicts of interest

There are no conflicts of interest.


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