Socio-demographic characteristics of adults screened for HIV/AIDS in a rural community in Benue state, Nigeria

Background: Benue state has been considered among the `hot zones' for HIV/AIDS in Nigeria with a prevalence rate of 9.3 among adults aged 15 to 45 years. Yet; there is paucity of information on the socio-demographic factors associated with this level of prevalence. We hereby report the prevalence and socio-demographic factors associated with HIV among adults in Abwa-Mbagene; Benue state; Nigeria. Methods: Adults in Abwa-Mbagene community who accepted to participate between 9th and 24th of August 2007 were recruited. After counselling; screening was done using `Determine HIV' kit. Results: 153 subjects (74 males and 79 females) were recruited. Their age ranges from 15 to 60 years (Mean: 26.2years). Fourty-two (27.5) consisting of 12 (16.2) males and 30 (38) females were positive for HIV (male to female ratio; 2:5). The prevalence of HIV was higher among the divorcees (50); those whose level of education was primary school (41.3) and below and; farmers (60). Majority (96) knows AIDS exists; 85are informed on mode and prevention of HIV transmission. Cases of AIDS deaths; unprotected casual sex; blood transfusion with unscreened blood and polygamy are common in the community. The single most important cultural factors in HIV transmission identified is indulgence in night parties; which increased the rate of unprotected casual sex. Conclusion: This community represents a high HIV/AIDS prevalence spot in Benue State; Nigeria. There is therefore the need for the establishment of HIV Counselling and Testing (HCT); Prevention of Mother-To-Child Transmission (PMTCT); save blood and antiretroviral treatment services in the community. Vocational centers to engage single women and improve their financial state will boost preventive strategies. Finally; partnership with community leaders towards discouraging night parties will reduce the prevalence of HIV in the community

Effect of demographic variables on cytomegalovirus antibody seropositivity among prospective blood donors in Jos, Nigeria.

BACKGROUND: Cytomegalovirus, otherwise called human herpes virus type 5, is a transfusion transmissible pathogen responsible for significant morbidity and mortality among various groups of individuals with damaged or impaired host immunity. Although it has a worldwide distribution, the infection is thought to be more widespread in developing countries where certain demographic factors and living conditions are thought to be responsible for the observed increased prevalence of this infection. OBJECTIVES: The aim of this study is to evaluate the effect of living conditions, using certain selected demographic parameters, on CMV seropositivity, among blood donors in Jos. PATIENTS AND METHODS: A total of 200 prospective blood donors who presented for bleeding were recruited consecutively into the study. Questionnaire was used to obtain the personal, educational, social and demographic data of donors. Screening for CMV antibodies was performed on each serum sample using ELISA kit ("DIALAB", Austria) (www.dialab.at). RESULTS: The relationship between the extent of crowding and CMV status of donors was statistically significant, p<0.05. Other studied donor demographic parameters (source of drinking water, place of abode and type of toilet facility) did not statistically influence donor CMV status, p>0.05. CONCLUSION: Our study showed that overcrowding was the most significant factor that statistically influenced donor CMV status in Jos, Nigeria. There is, therefore, an urgent need for concerted effort to handle the problem of overcrowding in developing countries and Nigeria in particular.

Effect of Demographic Variables on Cytomegalovirus Antibody Seropositivity among Prospective Blood Donors in Jos, Nigeria.

BACKGROUND: Cytomegalovirus, otherwise called human herpes virus type 5, is a transfusion transmissible pathogen responsible for significant morbidity and mortality among various groups of individuals with damaged or impaired host immunity. Although it has a worldwide distribution, the infection is thought to be more widespread in developing countries where certain demographic factors and living conditions are thought to be responsible for the observed increased prevalence of this infection. OBJECTIVES: The aim of this study is to evaluate the effect of living conditions, using certain selected demographic parameters, on CMV seropositivity, among blood donors in Jos. PATIENTS AND METHODS: A total of 200 prospective blood donors who presented for bleeding were recruited consecutively into the study. Questionnaire was used to obtain the personal, educational, social and demographic data of donors. Screening for CMV antibodies was performed on each serum sample using ELISA kit ("DIALAB", Austria) (www.dialab.at). RESULTS: The relationship between the extent of crowding and CMV status of donors was statistically significant, p<0.05. Other studied donor demographic parameters (source of drinking water, place of abode and type of toilet facility) did not statistically influence donor CMV status, p>0.05. CONCLUSION: Our study showed that overcrowding was the most significant factor that statistically influenced donor CMV status in Jos, Nigeria. There is, therefore, an urgent need for concerted effort to handle the problem of overcrowding in developing countries and Nigeria in particular.

Knowledge of sickle cell disease and haemoglobin electrophoresis: a survey of students of a tertiary institution.

BACKGROUND: Sickle Cell Disease (SCD) is the commonest genetic disease worldwide. Of the sickle cell control strategies, premarital genetic counselling is increasingly practised in many countries of the world. Knowledge of the citizenry of a nation about SCD constitutes an important variable that influences the acceptability, practice and success of premarital genetic counselling. A study of students of Benue State University, Makurdi was carried out to determine their current level of knowledge. METHOD: A cross sectional study involving 300 students of Benue State University, Makurdi; selected by a multistage stratified sampling technique, using self administered structured questionnaire, was carried out. RESULTS: Virtually all study respondents had at one time or the other heard about sickle cell disease. Based on the criteria used for knowledge scoring, less than half of the students (48%) demonstrated good knowledge. Overall Mean Score Knowledge (MSK) was 4.65 +/- 1.65. MSK was 4.58 +/- 1.66 and 4.74 +/- 1.64 for males and females respectively; there was no statistically significant difference (P > 0.05). However, having an affected relative suffering from sickle cell disease significantly influenced level of knowledge among study respondents (P < 0.05), but was not significantly associated with respondents knowing their haemoglobin phenotype. Only 141 students (47%) knew their haemoglobin phenotype. Level of knowledge about SCD did not significantly increase with age. Also, sex and religion did not significantly influence level of knowledge. CONCLUSION: The knowledge about SCD was poor and only a few knew their haemoglobin phenotype. If sickle cell disease control strategies must yield any significant results, more education about SCD, especially among students in tertiary institutions in Nigeria is recommended. The use of persons with SCD as peer educators/counsellors should be explored.

Prevalence of QTc prolongation in adult Nigerians with chronic heart failure.

BACKGROUND: The heart rate corrected QT interval (QTc) on the electrocardiogram (ECG) has been proposed as a risk factor for ventricular arrhythmias and death in apparently healthy populations, patients with myocardial infarction and diabetes mellitus. However, data on the significance of QTc prolongation in heart failure are scarce. OBJECTIVE: Our objective was to examine the prevalence of QTc prolongation in adult Nigerians with heart failure and its association with arrhythmias. METHODS: Ninety consecutive patients with heart failure were recruited along with 90 age-and sex-matched controls. All the subjects had a 12-lead ECG and a rhythm strip (lead II). The latter was used to calculate the QTc using the Bazett's formula. Left ventricular systolic and diastolic functions were assessed using a 2D guided m-mode and Doppler echocardiogram respectively. RESULTS: The mean age of the patients was 51.9 (16) years compared with 50.3 (15.2) years for the control group, p = 0.47. Mean left ventricular ejection fraction was significantly lower in the patients than in the controls (38.9 (11)% versus 72.2 (8)%), p = 0.001. The mean QTc was significantly prolonged in the patients than in the controls (0.472 (0.036) versus 0.390(0.032) respectively), p = 0.001. The prevalence of QTc prolongation was 63% in the patients against 4.4% in the controls. There was a significant association between ventricular arrhythmias and QTc prolongation. CONCLUSION: The results of this study shows that there is a high prevalence of QTc prolongation in adult Nigerians with heart failure and this may be harbinger for ventricular arrhythmias and sudden death.

Prognostic significance of QT interval prolongation in adult Nigerians with chronic heart failure.

BACKGROUND AND OBJECTIVES: Prognostic survival studies for heart-rate corrected QT interval in patients with chronic heart failure are few; although these patients are known to have a high risk of sudden cardiac death. This study was aimed at determining the mortality risk associated with prolonged QTc in Nigerians with heart failure. MATERIALS AND METHOD: Ninety-six consecutive patients with heart failure were recruited with 90 age and sex-matched controls. All the subjects had a 12-lead electrocardiogram at a paper speed of 25 mm/sec and a rhythm strip (lead II) at 50 mm/sec. The latter was used to calculate the QTc using the Bazett's formula. Left ventricular systolic and diastolic functions were assessed using 2D guided M-mode and Doppler echocardiogram respectively. They were followed-up for six months. RESULTS: Ninety-one patients and 90 controls completed the study. Five patients were lost to follow-up. The mean age (51.9 +/- 16 years) of the patients was similar to that of the controls (50.3 +/- 15) (P = 0.475). Twenty-eight (30.8%) patients died after 6 months of follow-up against none of the controls. The mean QTc was significantly longer in the non-survivors (0.494 +/- 0.027) than in the survivors (0.462 +/- 0.035) (P = 0.0001). The percentage mortality in patients with prolonged QTc against those with normal QTc was 41% and 14% respectively (P = 0.001). In the stepwise regression analysis, QTc was an independent predictor of mortality (R = 0.412, R2 = 0.17, P= 0.001). CONCLUSION: QTc prolongation is a predictor of mortality in CHF and may be an important adjunct in risk stratification of patients with heart failure.

Perception and attitude to epilepsy among teachers in primary, secondary and tertiary educational institutions in middle belt Nigeria.

Compared with the disability associated with repeated seizures or side-effects of antiepileptic medications, the social stigma associated with epilepsy is often a major handicap to people living with this condition. This study therefore looked at the knowledge, attitude and perception of teachers who see a lot of epileptics, relates on daily bases and have a high influence on students with epilepsy.Self-administered questionnaires were used to obtain information from 460 randomly selected teachers in primary, secondary and tertiary educational institutions in Kwara State-middle belt of Nigeria. The response rate was 75%. Almost all of the teachers had heard about epilepsy, but their awareness does not equate with the acceptance and understanding of epilepsy. About 30.5% believed that it could be contracted through the saliva of an epileptic, 27.7% thought it was synonymous with possession with evil spirit, while 10% misunderstood epilepsy for insanity. Close to one-fifth of the teachers were of the opinion that epileptic students have a below average mental capacity compared with other students and so cannot attainment the highest possible education. Negative attitude and bias towards epilepsy is still deeply ingrained among teachers in Nigeria. Apart from formal education, teachers need to have health education courses on common disease conditions such as epilepsy that are prevalent in school age. This might help to reduce prejudice and increase the acceptance of epileptic individuals into the classroom.

Female adolescent hawkers in Nigeria: HIV/AIDS-related knowledge; attitudes and behaviour

Background: HIV/AIDS is a pandemic with serious consequences. It affects such vulnerable groups as street children; adolescents and particularly females.Methodology: In 1999; a study was conducted among 686 randomly selected single females aged 10 to 24 years; who hawked food and other items in motor parks; in order to identify their HIV/AIDS risk and examine their possible role in its transmission; as a baseline for an intervention. Focus Group Discussion and adapted Participatory Action Research methodology were used to obtain information.Results: Eighty-one per cent had heard about HIV/AIDS and its sexual transmission. Thirty-eight per cent did not abstain from sexual intercourse; 54.0 of these had multiple partners; 38.0 used the condom; and 7.4 had ever been raped during the course of their jobs as hawkers. Their risk perception was poor.Conclusion: This target population is at high risk of contracting HIV infection and could transmit the infection within the community; thereby contributing significantly to the HIV/AIDS epidemic. Female adolescent hawkers should be targeted with appropriate programmes that would empower them for the prevention of HIV/AIDS

Ventricular arrhythmias: Q-T prolongation and left ventricular hypertrophy in adult Nigerians with hypertensive heart disease.

Seventy adult Nigerians with hypertensive heart disease (HHD) and 68 healthy controls were studied for ventricular arrhythmias (VA). The roles of QT prolongation and left ventricular hypertrophy in these arrhythmias were received. The mean age of the study population was 49.9 +/- 6.0 years. 14 (20.0%) patients had cardiac arrhythmias with 3 patients having premature ventricular contractions (PVC). Ten (14.3%) cases had QTc prolongation out of which 1 patient had PVC. Some factors that were found to be associated with QT prolongation in HHD include: left ventricular hypertrophy, persistently elevated systolic blood pressure and female gender. There was a positive correlation between left ventricular hypertrophy and QTc prolongation and also between QTc prolongation and frequency of ventricular arrhythmias.

Determinants of prognosis among black Africans with hypertensive heart failure.

One hundred and seven consecutive Black Africans hypertensive heart failure patients made of 52 Gambians and 55 Nigerians (51 males + 56 females) aged 53.6 +/- 12.1 years were followed-up for 12 months or till death. One-year survival curve was determined using Kaplan-Meiers method. The survivors and the deceased were compared using univariate and multivariate analysis. Mean blood pressures were 180.4 +/- 28.2 mmHg (range: 130-250 mmHg) systolic and 117.0 +/- 12.9 mmHg (range: 100-160 mmHg) diastolic. Duration of hypertension ranged from 0.5 to 23 years. The rate of undetected hypertension was 44%. Overall one-year survival rate was 71%. Twenty two percent of deaths occurred within the first 3 months of HHF. One-year survival rate among the survivors of this period was 89.4%. A strong negative correlation existed between cumulative survival and the duration of heart failure (y = 0.9812, x(2) = 0.1173, R = 0.965). Compared to the survivors, the deceased had significantly higher systolic blood pressure (191.9 +/- 32.2 mmHg versus 175.1 +/- 25.2 mmHg; P < 0.05), diastolic blood pressure (123.7 +/- 15.8mmHg versus 114.3 +/- 10.3 mmHg; P < 0.05), cardiothoracic index (69.2 +/- 3.9% versus 66.2 +/- 4.2%; P < 0.05) and serum creatinine (148.6 +/- 42.2 umol/L versus 113.8 +/- 36.4 umol/L; P < 0.05). Compared to the patients aged 40 or more years, patients aged below 40 years had significantly lower one-year survival rate (41.7% versus 74.1%; P < 0.05). One-year survival rate was significantly higher among patients on captopril medication than those without (75% versus 52.6%; P < 0.05). However, only serum creatinine had statistically differing values between the deceased and survivors (df = 1 SS = 10272, F = 7.60, p = 0.007). Basic clinical and biochemical parameters could therefore be useful prognostic markers in hypertensive heart failure.

An evaluation of Health Workers for Change in seven settings: a useful management and health system development tool.

This paper presents the findings of a multi-centre study assessing the impact of Health Workers for Change (HWFC) workshops in seven different primary care sites, based on the common core protocol described in this paper. The paper discusses a common methodology used by the studies, consisting of a triangulation of qualitative and quantitative methods. Such methodologies are inherently complex as they require comparisons across systems, sites and procedures. The studies were conducted in six sites in Africa and one site in Argentina. Generally, the intervention resulted either in positive change or in no change, except in the area of staff relationships where conflicts were more frequent after the intervention than before. This may reflect a willingness to confront problems or contentious issues. Implementing the HWFC workshops improved provider-client relations, facility level functioning and aspects of staff interrelationships, and had some impact at the system level. All studies indicated that overall health system development is essential for improved service provision including quality of care. The findings also indicated that this intervention complemented and could assist health sector reform efforts and can play a role in sensitizing health workers to gender issues. The paper concludes with a discussion of the robustness of the methodology used in the studies.

Arrhythmias: appraisal of symptoms by haemodynamic concepts.

Arryhthmias can afflict any heart, even in the absence of disease. Given that Cardiac Output (CO) is a product of heart rate and stroke volume, the end-result of brady- and tachy-arrhythmias is the same: low CO with symptoms of low-output state. In bradyarrhythmias, myocardial inotropy operates maximally but the product of stroke volume and slow heart rate yields a low CO. In tacharryhthmias, myocardial inotropy is redundant because the product of low stroke volume arising from low Diastolic Filling Time (DFT) and heart rate also yields a low CO. The hallmark of extrasystole is the duplex of symptoms: dizziness followed by palpitation.

Comparison of scalar with vectorial electrocardiogram in axis determination.

Axis deviation is one of the variables most commonly sought for in Electrocardiography (ECG). Although no one doubts the superiority of vector cardiography (VCG) as the most accurate in axis determination, most clinicians adopt the Hexaxial Reference System (HRS) of the 12-Lead ECG (12LS) as the most accessible for routine use. The question therefore arises: How accurate is the HRS? The 12LS and Orthogonal (Frank Lead) ECG (OLS) were recorded in 664 adult Nigerians without heart or metabolic diseases. Their VCG were constructed manually for the QRS complexes. On each subject, QRS axis was determined by three methods: the HRS for the 12LS, the trigonometric method for the OLS and the direction of the maximum deflection vector for the VCG. Axes by the three modalities were analysed and compared statistically as applicable to paired samples. The frontal plane (FP) QRS axis ranged between O degree and +90 degrees in 98.2% of cases by VCG, 96% by the OLS and 93.6% by the 12LS. There was excellent correlation between axes obtained by VCG and OLS (r = 0.85; P < 0.0001). It was lower but highly significant between VCG and the 12LS (r = 0.70; P < 0.0001). In the horizontal plane (HP), the 97 per centile distribution ranged from 240 degrees through 0 degree to 30 degrees; that is, posteriorly and to the left. In the left sagittal plane (LSP), the 95 per centile distribution ranged from 60 degrees counter-clockwise to 210 degrees; that is inferiorly and posteriorly. In a sample of healthy adult Nigerians, the QRS axis by VCG was located posteriorly, inferiorly and to the left. Axis determination by the 12LS is limited to the FP only, and it bears a good correlation with VCG. This commends the H RS as a condonable tool for estimating wave axis routinely and for epidemiologic studies.

The orthogonal and 12 lead ECG in adult negroes with systemic hypertension: comparison with age-matched control.

In a comparative ECG study of 288 hypertensive and 340 normal Nigerians, the following observations were made: a) The QRS voltage is high in normal Negroes but becomes significantly higher in hypertension (HBP). This suggests that the voltage criteria being used for LVH in Caucasians are not applicable to Negroes. b) The T wave amplitude diminishes in HBP culminating in ST-T flattening or down-sloping ST-segment with asymmetric T inversion, so called "Strain pattern" c) The Washington code for LVH (Rx amplitude > 2 mV, Rx + Rz > 3.4 mV and Rz duration > 0.06 sec) achieved a cumulative sensitivity of 70.7% with 83.5% specificity in males. In females, Rx > 2 mV, Rx + Rz > 2.6 mV and Rz duration > 0.07 sec. achieved a sensitivity of 71.6% with 92.4% specificity. d) In the 12-Lead system, RI > 1.1 mV Sv2 + Rv5 > 4.5 mV (male), Sv2 + Rv5 > 4.2 mV (female) and Tv6 < -0.05 mV achieved a cumulative sensitivity of 74.3% with 87.6% specificity in males; 72.3% with 91.8% respectively in females. It is suggested that further studies are required to authenticate these criteria for LVH in Negroes.

Contraceptive method choices among adolescents in a Nigerian tertiary institution.

This study was undertaken to describe adolescents, use of contraceptive methods and to examine factors that motivate their choice. Face-to-face interview of single, randomly selected 971 males and females aged 18-24 years in a Nigerian tertiary institution was conducted. Among sexually active males and females 72 percent and 81 percent respectively had ever used contraception. The commonest methods ever used by the males and females respectively were the condom (43 percent) and rhythm (31 percent). While females were mainly motivated by pregnancy prevention irrespective of the sexual relationship, the males were more concerned about disease prevention in unstable sexual relationships. However, adolescents whose choice was motivated by disease prevention did not choose the condom significantly more frequently than other methods. The college clinic, complimented by other programmes, should be strengthened for reproductive health services.

PIP: The use of contraceptives among adolescents is significantly different from that of older married couples, and it is influenced by educational, developmental, social, and psychological factors. This study provides information about the prevalence of contraceptive methods used among single adolescents in college and examines the factors that motivate their choice. 971 randomly selected males and females aged 18-24 years in a Nigerian tertiary institution were interviewed personally. The analysis of these 971 single adolescents having similar age distributions but different ethnic and religious backgrounds showed that most respondents (97.7% and 98.4% of males and females, respectively) knew at least one method of contraception. The commonest methods ever used were the condom (43%) and the rhythm method (31%). Females were mainly motivated by the need to prevent pregnancy, while males were more concerned with disease prevention in unstable sexual relationships. Adolescents who based their contraceptive choice on disease prevention did not choose the condom more frequently than other methods. Factors militating against contraceptive use by sexually experienced respondents included religious belief and fear of complications. The study recommends that college clinics be strengthened to manage reproductive health services. Programs should include information, education, and communication efforts targeted at these young people.

Sexual behaviour and condom acceptance among Nigerian drivers.

A survey of 180 randomly selected drivers was carried out in June 1994 in Ilorin, Nigeria in order to gain information about high-risk sexual behaviours, to ascertain condom use and to identify obstacles to condom acceptance so as to facilitate the design of an intervention to prevent Sexually Transmitted Diseases/Acquired Immuno-deficiency Disease in this target population. Data was collected through face-to-face interview. Three-quarters of the respondents were married. Multiplicity of sexual partners including casual and commercial contacts, was common. Half of the respondents engaged in high-risk sexual behaviour and a high proportion of them (60 percent) reported unwillingness to use the condom. This was mainly due to general dislike and lack of knowledge of the method. Risk perception was poor. These findings support the need for male reproductive health services especially for this sub-population.

PIP: 180 public transport drivers randomly selected from major motor parks in Ilorin, Nigeria, were surveyed in June 1994 to learn about their high-risk sexual behaviors, condom use, and obstacles to the acceptance of condoms. Data were collected through face-to-face interviews. The men were of mean age 33 years with a range of 19-53 years. 39.4% drove buses, 36.7% a car, 13.3% a truck or trailer, and 19% a lorry. 76.6% worked in urban areas. In the preceding 12 months, 16% of the single men had no sexual intercourse. However, 91% of the single sexually active men had multiple sex partners. Of the 98 (71.5%) married men who had extramarital sexual relationships, at least 72% had multiple extramarital sex partners. The prevalences of casual and commercial sex were 43% and 30.6%, respectively. Half of the drivers were involved in unstable sexual relationships. However, despite the high incidence of high-risk sex behavior, 60% reported being unwilling to use condoms, mainly due to their general dislike and ignorance of the method. The men poorly perceived the extent to which they were at risk of contracting HIV/AIDS and other sexually transmitted diseases through their sexual behavior.

Spatial magnitudes of instantaneous QRS and ST-T vectors in Nigerians.

Spatial magnitudes of instantaneous QRS and ST-T vectors were studied in 664 (333 male: 331 female) normal Nigerians aged 15 to 90 (Mean: 39.1 +/- 16.7) years. Measurements were made manually using 8 divisions (octets) per QRS or ST-T waves. Not only the maximum amplitude but also several identical points on the QRS, J-point and St-T curves were higher in males than females. The R wave, J-point and ST-T vectors were oriented leftwards, inferiorly and posteriorly. The ST-segments were not iso-electric. The rates of ventricular depolarization (dV/dt) varied from one octet to another with maximum dV/dt occurring during the third octet. Ventricular repolarization was slower with peak rates during the fifth octet. It is concluded that this technique is simple, informative and practicable at bedside; but further studies are required to explore its diagnostic usefulness in patients with heart disease.

The physiological basis of ST-T variations in the electrocardiogram: a review.

ST-T aberrations in the Negro involve both sexes, all age groups and all electrocardiogram (ECG) leads and are benign in the asymptomatic subject. This suggests that the variations have physiological basis and that alterations in the electrochemical processes occurring during repolarization would explain the ECG counterparts. While an isoelectric J-point suggests a temporal dissociation between phases 0 and 1 of the action potential, an elevated J-point suggests that phase 1 starts before the end of phase 0. If the current changes in phases 2 and 3 are the same, the ST-segment and T wave would form a continuum. It is suggested that in the Negro, the force producing repolarization overrides that producing slow depolarization during phases 2 and 3 and that the net result of the conflicting electrochemical processes accounts for the ST-T aberrations in the Negro race.

The orthogonal electrocardiogram in adult Nigerians: a preliminary report.

The Orthogonal ECG (Frank Lead System) was analysed in 664 asymptomatic normal Nigerians (333 Males: 331 Females) aged 15 to 90 years (mean: 39.1 +/- 16.7). The system gave the same information as the 12-Lead EGG concerning the heart rate and rhythm, durations of waves, intervals and segments, J-point elevation and ST-T variants. QRS morphology was of the left ventricular pattern with the Rs greater than R greater than qRS greater than qR patterns dominating the scene in X and Y leads, and QR much greater than qR in 2. All these suggest that the cardiac vector is oriented leftwards, inferiorly and posteriorly. There was no QS pattern in any lead. There was no Sx dominance, and no S wave in Z. Septal Q, recorded in 29.2% of X and 25.1% of Y did not exceed 0.3 seconds and 2 mm. There was no Tx or Ty inversion. Rather, they were upright (98.3% and 95.9% respectively) and rarely flat (1.7%:4.1%). The Orthogonal ECG is recommended as a simple, accurate system for clinical use either as a supplement to or in lieu of the 12-lead system.

The Orthogonal electrocardiogram in adult Nigerians : a priminary report

The orthogonal ECG was analysed in 664 asymptomatic normal Nigerians aged 15 to 90 years . The system gave the same information as the 12-lead ECG concerning the heart rate and rhythm; durations of waves; intervals and segments; J-point elevation and ST-T variants