"Echocardiography in Nigeria: use, problems, reproducibility and potentials"

GENDER DIFFERENCES IN THE CLINICAL PROFILE AND SOCIODEMOGRAPHIC CHARACTERISTICS OF DILATED CARDIOMYOPATHY IN IBADAN, NIGERIA

Background

Cardiomyopathies contribute about 18.2-40.2% (average- 21.4%) to the global burden of heart failure of which dilated cardiomyopathy (DCM) is a major cause. DCM is the second commonest cause of heart failure in Ibadan. The gender differences in the clinical profile has not been described in our setting.

Objective

In this study, we set out to describe the gender differences in the pattern and presentation of DCM at the University College Hospital, Ibadan, Nigeria.

Methods

This was an analysis of a prospectively collected data over a period of 5 years (August 1, 2016 to July 31, 2021).

Results

A total of 117 subjects, 88 males (75.3%) and 29 females (24.8%) aged 50.30 ± 14.7 years (range, 17 to 86 years). Males had significantly achieved a higher educational level than females (p = 0.004). Males were more likely to be employed and had more monthly income compared to females. Males were significantly more likely to use alcohol and smoke cigarette (p = 0.0001 and 0.001 respectively). Females were more likely to be in NYHA class III/IV. There was no statistically significant difference in the relationship between any medication and gender of participants (p > 0.05).

Conclusions

DCM is a disease of young and middle-aged adults in our population. The commonest age group was 20-39 years and there was male preponderance. There were some gender differences in the clinical profile of the disease in our environment.

Heart failure disease: An African perspective

Heart failure remains a health challenge in Africa, associated with significant rates of hospitalization, morbidity and mortality. The current review aims to summarize the most recent data on the epidemiology, aetiology, risk factors and management of heart failure, comparing countries in North Africa and sub-Saharan Africa. There is a paucity of data on heart failure epidemiology, aetiology and management, and on the sociodemographic characteristics of African patients with heart failure. Heart failure prevalence has been evaluated among all medical admissions or admissions to cardiac units or emergency departments in a few hospital-based studies conducted in countries in North Africa and sub-Saharan Africa. Common causes of heart failure in Africa include ischaemic heart disease, hypertensive heart disease, dilated cardiomyopathy and valvular heart disease. The aetiology of heart failure differs between countries in North Africa and sub-Saharan Africa. Diagnosing heart failure proves challenging in Africa because of a lack of basic tools and the necessary human resources. The principal drugs used frequently for heart failure therapy are lacking in sub-Saharan Africa. The clinical profile of heart failure in sub-Saharan Africa differs from that in North African countries; this is related to aetiological factors, socioeconomic status and availability of diagnostic tools. There is an evident need to establish a large multicentre registry to evaluate the heart failure burden in almost all African countries, and to highlight the major cardiovascular risk factors and co-morbidities. The present review highlights the importance of this syndrome in Africa, and calls for improvements in its early diagnosis, treatment and, possibly, prevention.

Echocardiographic Abnormalities and Determinants of 1-Month Outcome of Stroke Among West Africans in the SIREN Study

Background

Little is known about the relationship between echocardiographic abnormalities and outcome among patients with acute stroke. We investigated the pattern and association of baseline echocardiographic variables with 1‐month disability and mortality among patients with stroke in the SIREN (Stroke Investigative Research and Education Network) study.

Methods and Results

We enrolled and followed up consecutive 1020 adult patients with acute stroke with baseline transthoracic echocardiography from west Africa. To explore the relationship between echocardiographic variables and 1‐month disability (using modified Rankin scale >3) and fatality, regression models were fitted. Relative risks were computed with 95% CIs. The participants comprised 60% men with a mean age of 59.2±14.6 years. Ischemic stroke was associated with smaller aortic root diameter (30.2 versus 32.5, P=0.018) and septal (16.8 versus 19.1, P<0.001) and posterior wall thickness at systole (18.9 versus 21.5, P=0.004). Over 90% of patients with stroke had abnormal left ventricular (LV) geometry with eccentric hypertrophy predominating (56.1%). Of 13 candidate variables investigated, only baseline abnormal LV geometry (concentric hypertrophy) was weakly associated with 1‐month disability (unadjusted relative risk, 1.80; 95% CI, 0.97–5.73). Severe LV systolic dysfunction was significantly associated with increased 1‐month mortality (unadjusted relative risk, 3.05; 95% CI, 1.36–6.83).

Conclusions

Nine of 10 patients with acute stroke had abnormal LV geometry and a third had systolic dysfunction. Severe LV systolic dysfunction was significantly associated with 1 month mortality. Larger studies are required to establish the independent effect and unravel predictive accuracy of this association.

The Association of Epicardial Adipose Tissue and the Metabolic Syndrome in Community Participants in South Africa

Background:

We sought to determine the association of echocardiographically derived epicardial adipose tissue (EAT) thickness, which is a component of visceral adipose tissue, with the metabolic syndrome (MetS) in a cohort of randomly selected community participants.

Methods:

South African-Asian Indians aged 15–64 years were recruited over a 2-year period after informed consent was obtained. All participants who had complete measurements done for biochemistry and echocardiography (using established criteria), were dichotomized into the MetS or non-MetS groups defined according to the harmonized criteria.

Results:

Of the 953 (232 men and 721 women) participants recruited, 47.1% (448) were classified with the MetS. These participants had larger waist circumference and body mass index (P < 0.001), with larger LA volumes and diameter, thicker ventricular walls, higher left ventricular mass, relative wall thickness, and EAT (P < 0.001). There was a corresponding increase in EAT thickness with increasing number of MetS risk factors at the transition from 0 MetS factors to 1 (95% confidence interval [CI] −0.8; −0.2) and from 2 to 3 MetS factors (95% CI −0.9; −0.4). The AUC of the receiver operator curve was highest for triglycerides (0.845), followed by fasting plasma glucose (0.795) and then EAT (0.789). An EAT value of <3.6 mm predicted the presence of the MetS with a 78% sensitivity and 70% specificity. Using backward stepwise logistic regression, the most significant independent determinants of the MetS after adjusting for age, gender, and type 2 diabetes mellitus, was fasting plasma glucose (odds ratio [OR] = 1.2), triglycerides (OR = 7.1), and EAT (OR = 2.3).

Conclusion:

Although EAT is associated with the MetS, and can identify individuals at increased cardiometabolic risk, it has a limited additional role compared to current risk markers.

An assessment of the clinical utility of echocardiography criteria in a Tertiary Health Center

Background:

The rising prevalence of cardiovascular diseases in the population has increased the demand for cardiovascular imaging procedures (specifically echocardiography) in our center.

Aim:

To determine the percentage of appropriate indications for echocardiography.

Materials and Methods:

This was a prospective study conducted over a period of 1 year in the Department of Medicine of a Tertiary Health Care Center. The clinical diagnoses by the referring clinician and the indications (specific reasons for the study) for the echocardiography were consecutively recorded. The age and gender of the patients were also recorded. The indications were given a score of one to nine according to the revised appropriate use criteria of the American College of Cardiology Foundation and the American Society of Echocardiography (ASE). These indications were then classified into appropriate, inappropriate or uncertain based on the score. (1-3)-inappropriate use, (4-6) were derived.

Results:

There were 25 indications, 16 (64%) were appropriate, 6 (24%) were inappropriate and three (12%) were rated as uncertain.

Conclusion:

Sixty-four percent of the indications for echocardiography are appropriate for the procedure. This implies that the criteria for echocardiography are yet to be fully implemented resulting in overutilization of the procedure.

The proposed role of plasma NT pro-brain natriuretic peptide in assessing cardiac remodelling in hypertensive African subjects

AIM

Although plasma NT-proBNP differentiates hypertension (HT) with or without left ventricular hypertrophy (LVH) from hypertensive heart failure (HHF), most of the published data are based on studies in Western populations. Also, most previous studies did not consider left ventricular (LV) diastolic function and right ventricular (RV) function. We therefore examined the relation between NT-proBNP on LV and RV remodelling in an African hypertensive cohort.

METHODS

Subjects were subdivided into three groups after echocardiography: hypertensives without LVH (HT) (n = 83); hypertensives with LVH (HT + LVH) (n = 50); and those with hypertensive heart failure (HHF) (n = 77).

RESULTS

Subjects with HHF had significantly higher NT-proBNP levels compared to the HT + LVH group (p < 0.0002). NT-proBNP correlated positively with right atrial area, an indirect measure of RV function.

CONCLUSIONS

NT-proBNP is proposed as a useful biomarker in differentiating hypertension with or without LVH from hypertensive heart failure in black hypertensive subjects.

Hypertensive heart failure in Nigerian Africans: insights from the Abeokuta Heart Failure Registry

Data from the Abeokuta Heart Failure Registry were used to determine the clinical characteristics, mode of treatment, and short- and medium-term outcomes of patients with hypertensive heart failure. A total of 320 patients were consecutively studied, comprising 184 men (57.5%) and 136 women (42.5%) aged 58.4±12.4 and 60.6±14.5 years, respectively. Most patients (80%) presented with New York Heart Association functional class III or IV and around one third (35%) had preserved systolic function. Median hospital stay was 9 days (interquartile range 5-21) while intra-hospital mortality was 3.4%. The 30-day, 90-day, and 180-day mortality rates were 0.9% (95% confidence interval, -0.2 to 3.5), 3.5% (95% confidence interval, -1.7 to 7.3), and 11.7% (95% confidence interval, -7.8 to 17.5), respectively. In a multiple logistic regression analysis, only serum creatinine was an independent predictor of mortality at 180 days (adjusted odds ratio, 1.76; 95% confidence interval, -1.17 to 2.64). Hypertension is the most common etiological risk factor for heart failure in Nigeria. Most patients present in the fourth decade of life with severe heart failure and secondary valvular dysfunction and significant in-hospital mortality.

Reproducibility of left ventricular mass by echocardiogram in the ELSA-Brasil

Background

Echocardiography, though non-invasive and having relatively low-cost, presents issues of variability which can limit its use in epidemiological studies.

Objective

To evaluate left ventricular mass reproducibility when assessed at acquisition (online) compared to when assessed at a reading center after electronic transmission (offline) and also when assessed by different readers at the reading center.

Methods

Echocardiographers from the 6 ELSA-Brasil study investigation centers measured the left ventricular mass online during the acquisition from 124 studies before transmitting to the reading center, where studies were read according to the study protocol. Half of these studies were blindly read by a second reader in the reading center.

Results

From the 124 echocardiograms, 5 (4%) were considered not measurable. Among the remaining 119, 72 (61%) were women, mean age was 50.2 ± 7.0 years and 2 had structural myocardial abnormalities. Images were considered to be optimal/ good by the reading center for 110 (92.4%) cases. No significant difference existed between online and offline measurements (1,29 g, CI 95% −3.60-6.19), and the intraclass correlation coefficient between them was 0.79 (CI 95% 0.71-0.85). For images read by two readers, the intraclass correlation coefficient was 0.86 (CI 95% 0.78-0.91).

Conclusion

There were no significant drifts between online and offline left ventricular mass measurements, and reproducibility was similar to that described in previous studies. Central quantitative assessment of echocardiographic studies in reading centers, as performed in the ELSA-Brasil study, is feasible and useful in clinical and epidemiological studies performed in our setting.

Quality Control and Reproducibility in M-Mode, Two-Dimensional, and Speckle Tracking Echocardiography Acquisition and Analysis: The CARDIA Study, Year 25 Examination Experience

INTRODUCTION

Few large studies describe quality control procedures and reproducibility findings in cardiovascular ultrasound, particularly in novel techniques such as speckle tracking echocardiography (STE). We evaluate the echocardiography assessment performance in the Coronary Artery Risk Development in Young Adults (CARDIA) study Year 25 (Y25) examination (2010-2011) and report findings from a quality control and reproducibility program conducted to assess Field Center image acquisition and reading center (RC) accuracy.

METHODS

The CARDIA Y25 examination had 3475 echocardiograms performed in 4 US Field Centers and analyzed in a RC, assessing standard echocardiography (LA dimension, aortic root, LV mass, LV end-diastolic volume [LVEDV], ejection fraction [LVEF]), and STE (two- and four-chamber longitudinal, circumferential, and radial strains). Reproducibility was assessed using intraclass correlation coefficients (ICC), coefficients of variation (CV), and Bland-Altman plots.

RESULTS

For standard echocardiography reproducibility, LV mass and LVEDV consistently had CV above 10% and aortic root below 6%. Intra-sonographer aortic root and LV mass had the most robust values of ICC in standard echocardiography. For STE, the number of properly tracking segments was above 80% in short-axis and four-chamber and 58% in two-chamber views. Longitudinal strain parameters were the most robust and radial strain showed the highest variation. Comparing Field Centers with echocardiography RC STE readings, mean differences ranged from 0.4% to 4.1% and ICC from 0.37 to 0.66, with robust results for longitudinal strains.

CONCLUSION

Echocardiography image acquisition and reading processes in the CARDIA study were highly reproducible, including robust results for STE analysis. Consistent quality control may increase the reliability of echocardiography measurements in large cohort studies.

Short-term outcomes after hospital discharge in patients admitted with heart failure in Abeokuta, Nigeria: data from the Abeokuta Heart Failure Registry

Background

Compared to other regions of the world, there is a paucity of data on the short-term outcome of acute heart failure (AHF) in Africa’s most populous country, Nigeria. We examined the six-month outcomes (including case fatalities) in 285 of 309 AHF subjects admitted with HF to a tertiary hospital in Abeokuta, Nigeria.

Methods

The study cohort of 285 subjects comprised 150 men (52.6%) and 135 women (47.4%) with a mean age of 56.3 ± 15.6 years and the majority in NYHA class III (75%).

Results

There were a number of differences according to the subject’s gender; men being older and more likely to present with hypertensive heart disease (with greater left ventricular mass) while also having greater systolic dysfunction. Mean length of stay was 10.5 ± 5.9 days. Mean follow up was 205 days, with 23 deaths and 20 lost to follow up. At 30 days, 4.2% (95% CI: 2.4–7.3%) had died and by 180 days this had increased to 7.5% (95% CI: 4.7–11.2%); with those subjects with pericardial disease demonstrating the highest initial mortality rate. Over the same period, 13.9% of the cohort was re-admitted at least once.

Conclusions

The characteristics of this AHF cohort in Nigeria were different from those reported in high-income countries. Cases were relatively younger and presented with non-ischaemic aetiological risk factors for HF, especially hypertensive heart disease. Moreover, mortality and re-admission rates were relatively lower, suggesting region-specific strategies are required to improve health outcomes.

Contemporary profile of acute heart failure in Southern Nigeria: data from the Abeokuta Heart Failure Clinical Registry

OBJECTIVES

The aim of this study was to determine the contemporary profile, clinical characteristics, and intrahospital outcomes of acute heart failure (AHF) in an African urban community.

BACKGROUND

There are limited data on the current burden and characteristics of AHF in Nigerian Africans.

METHODS

Comprehensive and detailed clinical and sociodemographic data were prospectively collected from 452 consecutive patients presenting with AHF to the only tertiary hospital in Abeokuta, Nigeria (population about 1 million) over a 2-year period.

RESULTS

The mean age was 56.6 ± 15.3 years (57.3 ± 13.4 years for men, 55.7 ± 17.1 years for women), and 204 patients (45.1%) were women. Overall, 415 subjects (91.8%) presented with de novo AHF. The most common risk factor for heart failure was hypertension (pre-existing in 64.3% of patients). Type 2 diabetes mellitus was present in 41 patients (10.0%). Hypertensive heart failure was the most common etiological cause of heart failure, responsible for 78.5% of cases. Dilated cardiomyopathy (7.5%), cor pulmonale (4.4%), pericardial disease (3.3%), rheumatic heart disease (2.4%), and ischemic heart disease were less common (0.4%) causes. The majority of subjects (71.2%) presented with left ventricular dysfunction (mean left ventricular ejection fraction 43.9 ± 9.0%), with valvular dysfunction and abnormal left ventricular geometry frequently documented. The mean duration of hospital stay was 11.4 ± 9.1 days, and intrahospital mortality was 3.8%.

CONCLUSIONS

Compared with those in high-income countries, patients presenting with AHF in Abeokuta, Nigeria, are relatively younger and still of working age. It is also more common in men and associated with severe symptoms because of late presentation. Intrahospital mortality is similar to that in other parts of the world.

Spectrum of Echocardiographic Abnormalities among 168 Consecutive Referrals to an Urban Private Hospital in South-Western Nigeria

Trans-thoracic echocardiography (TTE) is an important non-invasive cardiac examination that provides structural and functional information. It is useful in the diagnosis of cardiac diseases and often guides the management and follow-up of patients with cardiovascular diseases (CVD). The study aimed to present an audit of the echocardiograms performed in an urban private hospital over a two-year period in order to define the pattern of cardiac diseases in our center. Echocardiogram reports of 168 consecutive patients performed between May 2011 and April 2013 at an organized private sector hospital in Lagos, south-west Nigeria were reviewed. Studies were performed with a Toshiba Nemio XG ultrasound machine. The data obtained were analyzed for mean age, sex, clinical indications, and echocardiographic diagnosis in the study subjects. A total of 168 echocardiography reports were examined, comprising of 92 males (54.8%) and 76 females (45.2%). The age range of the subjects was 10-76 years (mean 42.5 ± 12.1 years). The commonest indication for echocardiography was systemic hypertension and hypertension related causes (38.1%), followed by abnormal resting electrocardiogram (14.9%). Routine annual medical screening was the next most common indication, representing 13.1% of the indications for echocardiography. The other indications are as presented in Table 1. The echocardiogram was normal in 64.3% of the subjects. The commonest abnormality detected was hypertensive heart disease (HHD); accounting for 9.6% of the subjects studied. Isolated atrial enlargement (left, right, or bi-atrial) was the next most common abnormality accounting for 6% of the echocardiographic diagnosis. Pulmonary hypertension was the next most common diagnosis accounting for 4.8% of our findings. The other echocardiographic diagnoses are as listed in Table 2. Hypertension represents the commonest indication for echocardiography. Normal echocardiogram was the commonest echocardiographic finding while HHD was the commonest echocardiographic abnormality. The prevalence of ischemic heart disease by echocardiography was 2.4%. There was no case of rheumatic heart disease (RHD). The prevalence of hypertrophic cardiomyopathy (HCM) was 1.2%. Ease of access to echocardiography may influence the findings in an echocardiographic audit and policy makers should incorporate appropriateness criteria into their guidelines for reimbursement.

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

Background

Echocardiography remains a key noninvasive cardiac investigative tool in the management of patients, especially in a developing economy like Nigeria. In this study, we investigated the indications for transthoracic echocardiography and spectrum of cardiac disease found in patients referred to our cardiac unit for echocardiography.

Methods

A prospective two-dimensional, pulsed, continuous, and color-flow Doppler echocardiographic evaluation was done using the transthoracic approach in 2501 patients over an eight-year period. Univariate data analysis was performed for mean age, gender, clinical indications, and diagnoses.

Results

The subject age range was less than 12 months to 97 years (mean 52.39 years). There were 1352 (54.06%) males and 1149 (45.94%) females. The most common indication for echocardiography was hypertension (52.1%) followed by congestive cardiac failure (13.9%). Others were for screening (6.1%), arrhythmias (5%), cerebrovascular disease (5%), chest pain (3.3%), chronic kidney disease (3.2%), congenital heart disease (2.6%), cardiomyopathy (1.8%), rheumatic heart disease (1.7%), diabetes mellitus (1.3%), thyrocardiac disease (1.2%), ischemic heart disease (1.2%), and pericardial disease (1.1%). The echocardiographic diagnosis was hypertensive heart disease in 59.4% of subjects and normal in 14.1%. Other echocardiographic diagnoses included rheumatic heart disease (3.1%), congenital heart disease (2.1%), cardiomyopathy (1.7%), pericardial disease (1.1%), and ischemic heart disease (0.1%).

Conclusion

Hypertension and its cardiac complications is the most common echocardiographic indication and diagnosis at our unit.

Prevalence of asymptomatic left ventricular systolic dysfunction in hypertensive Nigerians: echocardiographic study of 832 subjects

BACKGROUND

We sought to determine the prevalence of echocardiographically determined left ventricular systolic dysfunction in asymptomatic hypertensive subjects seen in Abeokuta, Nigeria.

METHODS

Echocardiography was performed in 832 consecutive hypertensive subjects referred for cardiac evaluation over a three-year period.

RESULTS

Data were obtained in 832 subjects (50.1% women) aged 56.0 ± 12.7 years (men 56.9 ± 13.3 years, women 55.0 ± 12.0 years, range 15-88). The prevalence of left ventricular systolic dysfunction (LVSD) was 18.1% in the study population (mild LVSD = 9.6%, moderate LVSD = 3.7% and severe LVSD = 4.8%). In a multivariate analysis, male gender, body mass index and LV mass were the predictors of LVSD.

CONCLUSION

Significant numbers of hypertensive subjects in this study had varying degrees of left ventricular systolic dysfunction. Early introduction of disease-modifying drugs in these patients, such as angiotensin converting enzyme inhibitors or angiotensin receptor blockers may retard or prevent the progression to overt heart failure.

Spectrum of heart diseases in a new cardiac service in Nigeria: an echocardiographic study of 1441 subjects in Abeokuta

BACKGROUND

Echocardiography is a non-invasive, relatively cheap and useful imaging technique for the evaluation of cardiac diseases. The procedure has reliable levels of accuracy. Echocardiography commenced at the Federal medical centre Abeokuta on September 9, 2005.The aim of this study is to report our experience with the procedure, and to define the clinical cases seen in our setting.

METHODS

This is a retrospective analysis of a prospectively collected data. Echocardiography was performed using Aloka SSD 1,100 echocardiograph equipped with 2.5-5.0 MHz transducer

RESULTS

During the period of 18 months under review (September 2005-February 2007), 1629 procedures were performed. The reports of 188 echocardiograms were excluded due to poor echo-window, repeated procedure or incomplete report. 1441 reports were reviewed for demographic parameter, indications for the procedure and the main echocardiographic diagnoses.The mean age of the 1441 individuals studied was 54 +/- 14.3 years (15-90). There were 744 men and 697 women. Eight hundred and seventeen subjects (56.7%) had hypertensive heart disease, 53 subjects (3.7%) had rheumatic heart disease while 44(3.0%) had dilated cardiomyopathy. Pericardial diseases, cor-pulmonale, ischaemic heart disease, congenital heart diseases, diabetic heart disease, thyroid heart disease, sickle cell cardiopathy were present in 26(1.8%), 23(1.6%), 9(0.6%), 6(0.4%), 6(0.4%), 6(0.4%), 1(0.1%), and 1(0.1%) respectively. Four hundred and forty nine (31.2%) subjects had normal study.

CONCLUSION

Hypertensive heart disease was found to be the most prevalent cardiac condition in this study. The relatively frequent diagnoses of rheumatic heart disease, cardiomyopathies and pericardial diseases reflect the impact of infections and infestations on the cardiovascular health of adult Nigerians.We suggest that prevention and treatment of cardiac diseases in our setting should among other things focus on blood pressure control and early treatment of infections causing heart diseases.