Pattern of Right Ventricular Changes in Patients with Uncomplicated Systemic Hypertension at a Tertiary Centre in Southwest Nigeria.

BACKGROUND AND AIMS: Hypertension is an independent risk factor for cardiovascular complications. The effect of systemic hypertension on the right ventricle (RV) has received less attention probably due to its complex structure and location. The aim of the study was to assess the effect of systemic hypertension on the structure and function of the right ventricle using transthoracic echocardiography. METHOD: One hundred hypertensives and 100 healthy controls were recruited into the study. Transthoracic echocardiography was used to measure RV wall thickness (RVWT) in diastole, RV internal dimensions in diastole, tricuspid annular plane systolic excursion (TAPSE), right ventricular filling velocities (TE and TA), and RV systolic excursion velocity (RVSm). These measurements were repeated on the left ventricle. RESULTS: There was significantly thicker RV wall (0.51 + 0.08cm vs 0.44+0.08cm; p=0.001) in the hypertensive group and higher frequency of RV hypertrophy (48.45% vs 18.75%; p<0.001). Tricuspid annular plane systolic excursion (TAPSE) and the tricuspid annular peak systolic excursion velocity (TSm) were significantly lower in the hypertensive group (2.34+0.45cm vs 2.50+0.36cm; p=0.008, and 11.70+3.03cm/s vs 12.60+2.93cm/s p=0.039, respectively), though no participant had abnormal TAPSE. Tricuspid E/A ratio was lower in the hypertensive group (1.13+ 0.33 vs 1.24+0.27; p=0.011). The tricuspid E/A ratio had positive correlation with mitral E/A ratio. CONCLUSION: Right ventricular structural and functional changes are found in systemic hypertension, even in the absence of other systemic complications. These changes could have been mediated by ventricular interdependence and altered humoral factors.

CONTEXTES ET OBJECTIFS: L'hypertension artérielle est un facteur de risque indépendant pour les complications cardiovasculaires. L'effet de l'hypertension artérielle systémique sur le ventricule droit (VD) a reçu moins d'attention probablement en raison de sa structure complexe et de son emplacement. L'objectif de l'étude était d'évaluer l'effet de l'hypertension artérielle systémique sur la structure et la fonction du ventricule droit en utilisant l'échocardiographie transthoracique. MÉTHODE: Cent hypertendus et 100 témoins en bonne santé ont été recrutés dans l'étude. L'échocardiographie transthoracique a été utilisée pour mesurer l'épaisseur de la paroi du VD (EPVD) en diastole, les dimensions internes du VD en diastole, l'excursion plane systolique annulaire tricuspide (TAPSE), les vitesses de remplissage ventriculaire droit (TE et TA), et la vitesse d'excursion systolique ventriculaire droit (RVSm). Ces mesures ont été répétées sur le ventricule gauche. RÉSULTATS: Il y avait une paroi du VD significativement plus épaisse (0,51 ± 0,08 cm vs 0,44 ± 0,08 cm ; p=0,001) dans le groupe hypertendu et une fréquence plus élevée d'hypertrophie ventriculaire droite (48,45% vs 18,75% ; p<0,001). L'excursion plane systolique annulaire tricuspide (TAPSE) et la vitesse maximale systolique annulaire tricuspide (TSm) étaient significativement plus basses dans le groupe hypertendu (2,34 ± 0,45 cm vs 2,50 ± 0,36 cm ; p=0,008, et 11,70 ± 3,03 cm/s vs 12,60 ± 2,93 cm/s p=0,039, respectivement), bien qu'aucun participant n'ait eu de TAPSE anormal. Le rapport E/A tricuspide était plus bas dans le groupe hypertendu (1,13 ± 0,33 vs 1,24 ± 0,27 ; p=0,011). Le rapport E/A tricuspide avait une corrélation positive avec le rapport E/A mitral. CONCLUSION: Des modifications structurales et fonctionnelles du ventricule droit sont retrouvées dans l'hypertension artérielle systémique, même en l'absence d'autres complications systémiques. Ces changements pourraient avoir été médiés par l'interdépendance ventriculaire et des facteurs humoraux modifiés. MOTS-CLÉS: Hypertension ; Échocardiographie ; Hypertrophie ventriculaire droite ; Dysfonction diastolique ventriculaire droit.

Making the Transition From Cardiac Missions to Autonomous Heart Surgery at a Nigerian Teaching Hospital: Challenges and Lessons Learned.

Open-Heart Surgery at the Lagos State University Teaching Hospital commenced in 2004. Early years were based on a Cardiac Mission Model, but since 2017 the focus was on the transition to a Local Team Model with autonomous Open-Heart Surgery. The aim of this study is to describe our progress in making this transition, highlight lessons learned, and detail the outstanding challenges to be overcome. This study is a retrospective analysis of prospectively maintained data from the Lagos State University Teaching Hospital cardiothoracic database and Nigeria Open-Heart Surgery Registry between November 2004 and December 2021. Data extracted included patient demographics, EuroSCORE II, operative procedure, operative category, lead surgeon, complications, and outcomes. Over the study period, 100 operations were done over 2 time periods, 51 operations between 2004 and 2011 (Cardiac Mission Period) and 49 operations between 2017 and 2021 (Transition Period). In the Cardiac Mission Period, 21.6% of the operations were done by the Local Team and in the Transition Period this increased to 85.7% of the operations completed. Overall mortality was 14%, dropping from 17.6% in the Cardiac Mission Period to 10.2% in the Transition Period. The Local Team is now gradually taking on more diverse cases while striving to maintain good outcomes. Our institution has successfully made the transition from Cardiac Missions to Autonomous Open-Heart Surgery without an increase in mortality and a gradual increase in surgical volumes. Lessons learned included a strategy to focus on adult surgery, avoidance of high-risk cases, and moving from free surgery toward an appropriate cost structure for program sustainability. Contributory factors to the successful transition include the active support of the hospital management (provision of appropriate infrastructure and equipment, investment in training of the Local Team), continued humanitarian international collaborations focused on skill transfer, and maintenance of Local Team skills by collaborations with other active cardiac centers in Nigeria. Remaining challenges include financing to bridge equipment gaps, maintenance and replacement of equipment as well as the evolution of a national health insurance schema that would ideally support Open-Heart Surgery for Nigerian patients. Until that time, patients and programs must rely on supplemental funding of surgery to increase surgical volumes.

Registry for Acute Coronary Events in Nigeria (RACE-Nigeria): Clinical Characterization, Management, and Outcome.

Background Coronary artery disease was hitherto a rarity in Africa. Acute coronary syndrome (ACS) accounts for coronary artery disease-related morbidity and mortality. Reports on ACS in Africa are few. Methods and Results We enrolled 1072 indigenous Nigerian people 59.2±12.4 years old (men, 66.8%) with ACS in an observational multicentered national registry (2013-2018). Outcome measures included incidence, intervention times, reperfusion rates, and 1-year mortality. The incidence of ACS was 59.1 people per 100 000 hospitalized adults per year, and comprised ST-segment-elevation myocardial infarction (48.7%), non-ST-segment-elevation myocardial infarction (24.5%), and unstable angina (26.8%). ACS frequency peaked 10 years earlier in men than women. Patients were predominantly from urban settings (87.3%). Median time from onset of symptoms to first medical contact (patients with ST-segment-elevation myocardial infarction) was 6 hours (interquartile range, 20.1 hours), and only 11.9% presented within a 12-hour time window. Traditional risk factors of coronary artery disease were observed. The coronary angiography rate was 42.4%. Reperfusion therapies included thrombolysis (17.1%), percutaneous coronary intervention (28.6%), and coronary artery bypass graft (11.2%). Guideline-based pharmacotherapy was adequate. Major adverse cardiac events were 30.8%, and in-hospital mortality was 8.1%. Mortality rates at 30 days, 3 months, 6 months, and 1 year were 8.7%, 9.9%, 10.9%, and 13.3%, respectively. Predictors of mortality included resuscitated cardiac arrest (odds ratio [OR], 50.0; 95% CI, 0.010-0.081), nonreperfusion (OR, 34.5; 95% CI, 0.004-0.221), pulmonary edema (OR, 11.1; 95% CI, 0.020-0.363), left ventricular diastolic dysfunction (OR, 4.1; 95% CI, 0.091-0.570), and left ventricular systolic dysfunction (OR, 2.1; 95% CI, 1.302-3.367). Conclusions ACS burden is rising in Nigeria, and patients are relatively young and from an urban setting. The system of care is evolving and is characterized by lack of capacity and low patient eligibility for reperfusion. We recommend preventive strategies and health care infrastructure-appropriate management guidelines.

Anticoagulation in pregnant women with mechanical heart valve prostheses: Case reports and a literature review.

The choice and regimen of anticoagulation therapy in pregnant women with mechanical valve prostheses have always been a daunting task. It is a delicate balance that takes into consideration the risk of thromboembolic complications in the mother and the risk of potential Warfarin embryopathy to the foetus. Medical practice in a low socioeconomic setting also has the peculiar challenge of financial constraints on the part of the patients and difficulties in monitoring the efficacy of anticoagulation therapy. We report our experience in managing two pregnant women with mechanical valve prostheses and review the existing literature on this complex but interesting subject.

Assessment of Plasma Sodium to Potassium Ratio, Renal Function, Markers of Oxidative Stress, Inflammation, and Endothelial Dysfunction in Nigerian Hypertensive Patients.

BACKGROUND: This study investigated plasma sodium/potassium ratio, markers of oxidative stress, renal function, and endothelial dysfunction in hypertensive Nigerians. MATERIALS AND METHODS: Five hundred forty-nine volunteers consisting of three hundred and twenty-four hypertensive and two hundred twenty-five controls participated in this study. Blood samples were collected from the participants and were analyzed for electrolytes, markers of oxidative stress, endothelial dysfunction, renal function, and inflammation, using ion-selective electrodes, spectrophotometric, and enzyme-linked immunosorbent assay methods, respectively. RESULTS: The mean systolic blood pressure, mean diastolic blood pressure, mean arterial blood pressure, and body mass index (BMI) were significantly elevated among the hypertensive group when compared with control (p < 0.001). The mean sodium increased, while potassium and bicarbonate (HCO3 -) decreased (p < 0.001) in hypertensive volunteers. The sodium-potassium ratio (Na+/K+) and urea were raised (p < 0.001) in the hypertensive group when compared with the control. Glutathione, superoxide dismutase, nitric oxide (NO), and catalase were significantly reduced (p < 0.001) while malondialdehyde (MDA), high-sensitivity C-reactive protein (hs-CRP), and ferritin were raised significantly (p < 0.001) in hypertensive participants. The odds of hypertension and its complications increased (p < 0.001) with an increase in BMI, Na+/K+, hs-CRP, MDA, and ferritin and a decrease in estimated glomerular filtration rate (eGFR), glutathione, superoxide dismutase, and catalase. CONCLUSION: An increase in Na+/K+, urea, hs-CRP, ferritin, MDA, and BMI and a decrease in eGFR, glutathione, and superoxide dismutase were associated with an increased risk of hypertension complication. Abnormal values of markers of oxidative stress, inflammation, and endothelial function could impact deleterious effects on the cardiovascular system among hypertensive Nigerians. A decreased bicarbonate possibly suggests an occult acid-base imbalance among hypertensive volunteers.

May Measurement Month 2017: screening for hypertension in Nigeria-Sub-Saharan Africa.

Hypertension and its complications are now responsible for about a quarter of emergency medical admissions in urban hospitals in Nigeria. It is the commonest risk factor for stroke, heart failure, chronic kidney disease, and dementia. Furthermore, high blood pressure is the commonest cause of sudden unexpected natural death in the country. Regrettably, the rate of awareness, treatment, and control is abysmally low in the country and in many parts of the world. May Measurement Month (MMM) is a global initiative of the International Society of Hypertension aimed at raising awareness of high blood pressure (BP) and to act as a temporary solution to the lack of screening programs worldwide. An opportunistic cross-sectional survey of volunteers aged ≥18 years was carried out in May 2017. Blood pressure measurement, the definition of hypertension and statistical analysis followed the standard MMM protocol. A total of 19 904 individuals with a mean age of 40.9 years, were screened during MMM17. After multiple imputation, 6709 (36.2%) had hypertension. Of individuals not receiving anti-hypertensive medication, 4140 (25.9%) were found to have hypertension. Of individuals receiving anti-hypertensive medication, 1449 (58.8%) had uncontrolled BP. MMM17 was one of the largest BP screening campaigns undertaken in Nigeria. A significant number of the participants were identified with hypertension (but not on any treatment) and uncontrolled BP despite being treated. These results suggest that opportunistic screening can identify significant numbers with raised BP.

Knowledge of the Nigerian Code of Health Research Ethics Among Biomedical Researchers in Southern Nigeria.

Responsibility for protection of research participants from harm and exploitation rests on Research Ethics Committees and principal investigators. The Nigerian National Code of Health Research Ethics defines responsibilities of stakeholders in research so its knowledge among researchers will likely aid ethical conduct of research. The levels of awareness and knowledge of the Code among biomedical researchers in southern Nigerian research institutions was assessed. Four institutions were selected using a stratified random sampling technique. Research participants were selected by purposive sampling and completed a pre-tested structured questionnaire. A total of 102 biomedical researchers completed the questionnaires. Thirty percent of the participants were aware of the National Code though 64% had attended at least one training seminar in research ethics. Twenty-five percent had a fairly acceptable knowledge (scores 50%-74%) and 10% had excellent knowledge of the code (score ≥75%). Ninety-five percent expressed intentions to learn more about the National Code and agreed that it is highly relevant to the ethical conduct of research. Awareness and knowledge of the Code were found to be very limited among biomedical researchers in southern Nigeria. There is need to improve awareness and knowledge through ethics seminars and training. Use of existing Nigeria-specific online training resources is also encouraged.