Electrocardiographic findings in sickle cell cardiovascular autonomic neuropathy.

BACKGROUND: There is a lack of data on the relationship between cardiovascular autonomic neuropathy (CAN) and electrocardiographic parameters in sickle cell anaemia. AIMS AND OBJECTIVES: The purpose of the study was to compare the electrocardiographic findings in adult sickle cell anaemia patients with CAN with those of patients without this complication. METHODS: A cross sectional study was done using 62 consecutively recruited sickle cell anaemia patients who met the inclusion criteria for the study. Cardiovascular autonomic dysfunction was determined based on abnormal values in at least two of five non-invasive tests: Valsalva manoeuver, heart rate variation during deep breathing, heart rate response to standing, blood pressure response to sustained hand grip, and blood pressure response to standing. The subjects were subsequently evaluated with electrocardiography. RESULTS: Sickle cell anaemia patients with CAN had statistically significantly increased P-wave duration (p < 0.001), PR-interval (p < 0.05) and QTc dispersion (p < 0.05) compared with patients without CAN. Significantly increased frequencies of Q waves and first degree atrio-ventricular block were found in patients with CAN than in those without CAN (p = 0.026, p = 0.014, respectively). Significant correlations were noted between the severity of CAN [number of abnormal autonomic function tests (AFT)] and (1) P-wave duration (p = 0.008), (2) PR- interval (p = 0.013). Significant association was found between the number of abnormal AFT and (1) presence of Q-waves, and (2) degree of anaemia (haematocrit class). CONCLUSION: Electrocardiographic features consistent with atrio-ventricular and ventricular repolarization abnormalities are associated with CAN in sickle cell anaemia. Further studies are required to evaluate the prognostic implications of these findings in sickle cell patients with cardiovascular autonomic dysfunction.

One year echocardiographic study of rheumatic heart disease at Enugu, Nigeria.

BACKGROUND: Rheumatic heart disease is one of the commonest causes of heart disease in Nigeria. Previous studies on rheumatic heart disease in Nigeria were either clinical or retrospective echocardiographic studies. This study was aimed at determining the burden of chronic rheumatic mitral valve disease, pattern of valvular involvement, severity and associated valvular lesions, using echocardiography. PATIENTS AND METHODS: Between May, 2004 and April 2005, patients with symptomatic rheumatic heart disease, seen in the cardiac clinics of University of Nigeria Teaching Hospital, Enugu, were recruited for the study. The patients were investigated non-invasively with M-mode, Two-dimensional, Pulsed wave, Continuous wave and colour flow Doppler echocardiographic techniques in order to assess the mitral and other intracardiac valves for evidence of rheumatic heart disease. RESULTS: There were a total of 55 patients, 39 (70.9%) females and 16 (29.1%) males with a mean age of 29.34 +/- 11.57 years. Mitral valve disease was found in 54 (98.2%) and isolated aortic valve disease in 1 (1.8%) of cases. Mitral regurgitation occurred in 64.8%, mixed mitral valve disease in 25.9% and pure mitral stenosis in 9.3%. Mitral valve disease was associated with aortic valve disease in 33.3%, with tricuspid valve disease in 24.1% and with functional pulmonary incompetence in 9.3% of cases. CONCLUSION: Rheumatic heart disease in Nigeria is essentially a disease of the mitral valve as seen elsewhere in the world. Echocardiography should be done routinely for patients with rheumatic heart disease to facilitate accurate diagnosis and definitive treatment.

The relationship between diastolic dysfunction and level of blood pressure in Blacks.

INTRODUCTION AND OBJECTIVE: Patients with essential hypertension are predisposed to impaired left ventricular relaxation, and consequently, diastolic dysfunction. Because diastolic dysfunction is an early marker of the pathological effects of hypertension on the heart, evaluating the relationship between the development of diastolic dysfunction and the level of blood pressure becomes pertinent. The aim of our study was to evaluate this relationship. PATIENTS AND METHODS: Between November 1998 and January 2000, 692 consecutive hypertensive patients, all Blacks, attending the medical outpatient and cardiac clinics of the University of Nigeria Teaching Hospital, Enugu, Nigeria were screened for the study. One hundred five of them, divided into 3 groups of 35 each according to levels of blood pressure, met the inclusion criteria. Thirty-five age and sex-matched normotensives were used in the control group. Clinical parameters, including systolic and diastolic blood pressures, and echocardiographic indices, were measured. RESULTS: A definite positive relationship between diastolic dysfunction and the level of the blood pressure was established, with the degree of diastolic dysfunction proportionate to increasing level of blood pressure (P<.001). A significant difference between the mean values of the diastolic dysfunction index (A/E ratio) in the hypertensive groups was evident (P<.05). While there was virtually no correlation found between normotensives and diastolic dysfunction (r=0.07), direct relationships existed between moderate and severe hypertensives and diastolic dysfunction (r=0.24 and 0.39 respectively). CONCLUSION: This study has demonstrated that diastolic dysfunction was significantly and progressively higher in the hypertensive groups when compared to the normotensive control group. Further studies, with a large number of patients, are recommended to determine population-based data on diastolic dysfunction and its other confounding variables in our environment, independent from the level of blood pressure.

Correlation of electrocardiogram with echocardiographic left ventricular mass in adult Nigerians with systemic hypertension.

Systemic hypertension, High Blood Pressure (HBP) is common in Nigeria with up to 10 to 15% prevalence among adults. HBP is readily complicated by left ventricular hypertrophy (LVH), recognised to herald a series of adverse outcomes in cardiovascular health. In order to device a method of assessment of LVH that is objective, readily available, affordable and easily operable in the face of soaring cost of the more recent techniques, correlation of electrocardiographic (ECG) LVH parameters was done with echocardiographic (ECHO) left ventricular mass (LVM). ECG is objective, affordable and easily operable, while ECHO is highly accurate for measurement of LVM. One hundred and fifty-five hypertensives were studied (123m; 32f). A statistically significant correlation was found with a maximum coefficient of 0.36 in males only. ECG can thus offer an objective alternative for assessment of LVH in HBP in males where ECHO is not available or practicable.

Clinical and electrocardiographic evaluation of sickle-cell anaemia patients with pulmonary hypertension.

Pulmonary hypertension is an emerging complication of sickle cell anaemia with associated increased risk of mortality. In order to evaluate the clinical and electrocardiographic findings in adult sickle-cell patients with pulmonary hypertension, a cross sectional study was conducted on sixty two sickle cell anaemia patients and sixty two age and sex matched normal controls. Elevated pulmonary artery pressures (PAP), defined by PAP ≥ 30 mm Hg on echocardiography, was demonstrated in 41.9% of patients with sickle cell anaemia and in 3.2% of the controls; χ(2) = 26.571, P < 0.001. Right ventricular hypertrophy, increased P-wave duration, QTc interval, and QTc dispersion were significantly associated with pulmonary hypertension. Significant correlation was found between mean PAP and (1) Frequency of crisis (Spearman correlation = 0.320; P = 0.011), (2) body mass index (Pearson's correlation = -0.297; P = 0.019), and (3) QTc interval (Pearson's correlation 0.261; P = 0.040). Pulmonary hypertension in adult sickle anaemia patients is associated with electrocardiographic evidence of right ventricular hypertrophy, and correlates significantly with frequency of vaso-occlusive crisis, and QTc interval. The observations by this study tend to suggest that these parameters could be useful for early detection and prevention of pulmonary hypertension in patients with sickle cell anaemia.

Pattern of Blood Pressure Indices among the Residents of a Rural Community in South East Nigeria.

Cardiovascular diseases (CVDs) are the main causes of death in industrialized countries, and are significant causes of morbidity and mortality in sub-Saharan Africa. Hypertension is the most common cardiovascular disease in Nigerians, and the risk of CVD associated with hypertension is independent of other risk factors. Despite the high level of awareness of its presence in the developed countries, the level of control is still poor. CVDs tend to be commoner in urban settlements, and it has been hypothesized that rural sub-Saharan Africa is at an early stage of epidemiological transition from communicable to non-communicable diseases (NCD) because of the gradual adoption of unhealthy lifestyles. This study aimed at describing the pattern of blood pressure indices among the hypertensive residents of a rural community in South East Nigeria. A total of 858 individuals comprising 247 males and 611 females took part in the study. 46.4% of the subjects had hypertension. Hypertension was commoner in the males (50.2% vs. 44.8%) (χ(2)(1) = 1.484; P = 0.223). The males were significantly older and heavier than the females while the females had higher mean values of BMI and WC. The prevalence of hypertension is becoming alarmingly high in the rural communities of sub-Saharan Africa.

Congestive heart failure in subjects with thyrotoxicosis in a black community.

INTRODUCTION: Thyroid hormone has profound effects on a number of metabolic processes in virtually all tissues but the cardiovascular manifestations are prominent usually creating a hyperdynamic circulatory state. Thyrotoxicosis is not a common cause of congestive heart failure among black communities. OBJECTIVES: To determine the hospital prevalence, clinical characteristics and echocardiographic findings in patients with thyrotoxicosis who present with congestive heart failure (CCF) in the eastern part of Nigeria. SUBJECTS AND METHODS: A total of 50 subjects aged 15 years and above who were diagnosed as thyrotoxic following clinical and thyroid function tests were consecutively recruited. Fifty age- and sex-matched controls with no clinical or biochemical evidence of thyrotoxicosis and no comorbidities were used as controls. Two-dimensional echocardiography was carried out on all the subjects. CCF was determined clinically and echocardiographically. RESULTS: Eight patients (5 females and 3 males) out of a total of 50 thyrotoxic patients presented with congestive heart failure. CONCLUSION: The study revealed that congestive heart failure can occur in thyrotoxicosis in spite of the associated hyperdynamic condition. The underlying mechanism may include direct damage by autoimmune myocarditis, congestive circulation secondary to excess sodium, and fluid retention.

Respiratory symptoms and ventilatory function tests in Nigerians with HIV infection.

BACKGROUND: The impact of the human immunodeficiency virus (HIV) infection on the respiratory system of Africans has been little studied. This study aimed to determine the pattern of respiratory symptoms and ventilatory functions in HIV infected Nigerians. METHODS: In this cross sectional study, Respiratory symptoms frequency, Forced vital capacity (FVC), Forced expiratory volume in one second (FEV(1)), FEV(1)/FVC ratio, Forced expiratory flow between 25% and 75% of FVC, were determined in 100 HIV positive subjects and compared with values in 100 HIV negative controls. RESULTS: HIV positive patients had significantly more respiratory symptoms and lower ventilatory function tests values compared to the matched controls (p<0.05). HIV patients with at least one respiratory symptom and those with CD4 count less than 200 cells/µl had lower ventilatory function values than their counterparts. 32% of the HIV patients had restrictive ventilatory functional impairment. (p<0.05). Using regression analysis, factors like HIV status, CD4 count and presence of respiratory symptoms were found to be associated with impairment in ventilatory functions. CONCLUSIONS: HIV infected patients had more frequent respiratory symptoms and lower ventilatory function values. Further lung function studies and CT scanning in HIV positive patients especially in those with respiratory symptoms are indicated.

Electocardiographic findings in adult Nigerians with sickle cell anaemia.

BACKGROUND: Cardiovascular system abnormalities are common causes of morbidity and mortality in sickle cell anaemia. OBJECTIVES: The study aims at determining the pattern of electrocardiographic changes in adult Nigerian sickle cell anaemia patients. METHODS: A descriptive cross sectional study was done on sixty sickle cell anaemia patients seen at the adult sickle cell clinic of University of Nigeria Teaching Hospital (UNTH) Enugu, and sixty age and sex matched normal controls. All the subjects had clinical evaluation as well as electrocardiographic examination. RESULTS: The mean heart rate, P-wave duration, P-wave dispersion, PR interval, QRS duration, QRS dispersion, QTc interval and QTc dispersion were significantly higher in the patients than in the control group. Electrocardiographic abnormalities identified by this study were: left ventricular hypertrophy (75%; 1.7%), left atrial enlargement (40%; 0%), biventricular hypertrophy (11%; 0), ST-segment elevation (10%; 0%) and increased P-wave and QTc dispersions. ST segment elevation was found more in patients with moderate and severe anaemia (P= 0.02, Spearman correlation r= 0.342; P= 0.007), CONCLUSION: Sickle cell anaemia is associated with significant electrocardiographic abnormalities. Further prospective studies are recommended to evaluate the prognostic significance of the electrocardiographic intervals dispersion on the long term disease outcome in sickle cell anaemia.

Arterial blood pressure in adult Nigerians with sickle cell anemia.

AIM AND OBJECTIVE: This study was aimed at comparing the arterial blood pressures in steady state adult sickle cell patients with those of age- and sex-matched healthy controls. METHODS: A descriptive cross-sectional study of 62 sickle cell anemia patients and 62 age- and sex-matched healthy controls was carried out in the adult outpatient sickle cell clinics and the cardiac center of the University of Nigeria Teaching Hospital (UNTH), Enugu, Nigeria. Brachial blood pressures were measured in the right arm in all subjects. RESULTS: Significant increase in pulse rate was found in the study subjects (87.68 ± 8.91 bpm) compared with the controls (72.13 ± 6.79 bpm) (p<0.05). The mean systolic blood pressure was comparable in the two groups. However, the patients had significantly lower diastolic blood pressure, lower mean arterial blood pressure, as well as a higher pulse pressure than the control subjects. Significant correlations were found between blood pressure indices and hematocrit, body mass index, frequency of crisis, and body surface area. CONCLUSION: Relatively lower arterial blood pressure is a significant finding in patients with sickle cell anemia. Hematocrit, frequency of crisis, body mass index, and body surface area are significant determinants of blood pressure indices in sickle cell anemia.

Ventricular septal defects at the University of Nigeria Teaching Hospital, Enugu: a review of echocardiogram records.

This research aimed to evaluate the prevalence of ventricular septal defect (VSD) and to determine the age and gender distribution of this defect and its common associated congenital cardiac anomalies among patients referred for echocardiographic examination at the echocardiography laboratory of the University of Nigeria Teaching Hospital, Enugu, Nigeria. Echocardiogram reports from the 10-year period February 1991-September 2001 were analysed. There were 2486 echocardiogram scans with an additional 334 repeat scans; 593 subjects had congenital anomalies, of which 165 (28%; 98 males and 67 females) had VSDs. The highest prevalence of VSDs (118; 70%) was in children age 0-9 years although VSDs were found in adults aged up to 50 years and above. Persistent ductus arteriosus and atrial septal defect were the commonest associated congenital anomalies. The study has shown that VSD is a relatively common congenital heart disease and that many patients present with VSD in adult life. There is a need for thorough scrutiny to be made for other cardiac anomalies in all patients with VSD, as well as for corrective surgery to be made affordable to those affected by this defect and other associated anomalies.