Cardiovascular Journal of Africa最新文献

Atrial fibrillation (AF) remains the most common arrhythmia. The sinus rhythm restoration procedure without adequate anticoagulant preparation may lead to a thromboembolic event in approximately 5-7% of patients. The initiation of oral anticoagulation significantly reduces this risk by inhibiting formation of embolic material in the heart cavities, especially in the left atrial appendage (LAA). However, there is a group of patients who develop embolic material in the LAA despite oral anticoagulation treatment. The best treatment method to dissolve thrombus in the LAA is not clear, due to the lack of studies with adequate power and endpoints that can determine the best management strategy. We present clinical trials comparing the efficacy and safety of oral anticoagulants in patients undergoing AF cardioversion. We evaluate the frequency of LAA thrombus formation in patients with AF on treatment with oral anticoagulants. Furthermore, we discuss the effectiveness of various treatment strategies on LAA thrombus resolution.

Background: Cardiovascular disease (CVD)-related admissions are on the increase in Nigeria and the rest of Africa. This study was carried out to highlight the burden, patterns and outcomes of CVD admissions in a tertiary hospital over a 16-year period in Lagos, Nigeria.

Methods: Admissions records of patients admitted into the medical wards within the study period (January 2002 to December 2017) were reviewed and relevant information pertaining to the study objectives was retrieved for analysis.

Results: There were a total of 21 369 medical admissions and 4 456 (20.8%) CVD-related admissions. A total of 3 582 medical deaths were recorded and 1 090 (30.4%) CVD-related deaths. The median age of the patients was 56.6 (46.0-68.0) years and 51.4% of these were males. Stroke, heart failure, hypertensive disease and acute coronary syndrome constituted 51.2, 36.2, 11.3 and 1.6% of all CVD admissions, respectively. There was a cumulative increase in the number of CVD admissions and deaths (p < 0.001, respectively) during the period under review.

Conclusions: CVD admissions are not only common in Nigeria, but there was also a temporal exponential increase in both the admission and death rates, most likely reflecting the epidemiological transition in Nigeria.

Aim: The Shexiang Baoxin pill (SBP) is a commonly used drug for the treatment of coronary artery disease in China. More recently, some studies have found that it improved coronary microvascular function. This study aimed to explore the possible mechanism by which the SBP promotes angiogenesis after acute myocardial infarction (AMI).

Methods: A rabbit model of acute myocardial infarction was established by ligating the left anterior descending coronary artery with silk thread, and the limb lead electrocardiogram was recorded to determine the success of the model. The rabbits were divided into a control group (SBP + normal rabbit group), a sham operation group, a saline + AMI group and an SBP + AMI group. There were 10 rabbits in each group. The animals were sacrificed and myocardial tissue was collected seven days after the operation. Haematoxylin-eosin staining was used to observe the histological changes in the rabbit myocardium in each group. The degree of acute myocardial infarction was observed with picric acid staining, which was used to detect the expression of vascular endothelial growth factor (VEGF), silent information regulator 1 (SIRT1), Beclin1 and mTOR protein in the myocardial tissue of each group. Immunofluorescence CD31-labelled microvascular density (MVD) was used to observe the vascular regeneration of the rabbits in each group.

Results: Compared with the normal saline + AMI group, the myocardial infarction area of the SBP + AMI group decreased and CD31 immunofluorescence-labelled MVD increased. Compared with the control and sham operation groups, the expression of VEGF, Beclin1 and mTOR in the normal saline + AMI group and the SBP + AMI group increased, while the expression of SIRT1 decreased. Compared with the normal saline + AMI group and the SBP + AMI group, the positive expression of VEGF, Beclin1, mTOR and SIRT1 in the SBP + AMI group was significantly increased.

Conclusion: Autophagy was enhanced after acute myocardial infarction. SBP may affect angiogenesis through the SIRT1/mTOR signalling pathway after acute myocardial infarction to inhibit ventricular remodelling and a decline in cardiac function.

Background: Right ventricular dysfunction carries a poorer prognosis in human immunodeficiency virus (HIV)-positive patients. The objectives of this study were to ascertain the prevalence of right ventricular systolic and diastolic dysfunction, as well as its predictors, in antiretroviral therapy-naïve HIV-positive patients.

Methods: Participants in this cross-sectional, descriptive study comprised 60 HIV-positive patients and 60 HIV-negative controls. All participants had transthoracic echocardiography done to assess right ventricular systolic and diastolic function. The HIV-positive patients had their CD4 counts measured.

Results: The mean age of the study population was 34.63 ± 8.7 years versus that of the controls (34.45 ± 9.40 years) (p = 1.000). Right ventricular systolic dysfunction was found in 11.6% of the HIV-positive patients versus the controls (3.33%, p = 0.166) while right ventricular diastolic dysfunction was found in 15.0% of HIV-positive patients versus the controls (1.7%, p = 0.021). The CD4 count did not contribute to the frequency and degree of right ventricular systolic or diastolic dysfunction.

Conclusion: Right ventricular systolic and diastolic dysfunction was common in treatment-naïve HIV-infected individuals but the frequency and degree were not associated with the CD4 count or other measured parameters.

Background: In dialysis patients, vascular calcification is a common complication and is closely related to the morbidity and mortality of cardiovascular disease. We performed a systematic review to determine the efficacy and safety of sodium thiosulfate (STS) in the progression of vascular calcification in dialysis patients with end-stage renal disease.

Methods: The PubMed, Web of Science, Embase, Cochrane Library, Wanfang, CNKI, China Biology Medicine disc and Weipu databases were searched up to 9 March 2022 for clinical trials to synthesise findings on the efficacy and safety of STS in the progression of vascular calcification in dialysis patients. The primary outcome was coronary artery calcification scores (CACS) or abdominal aortic calcification scores (AACS) or Kauppila index. The secondary outcome was pulse-wave velocity (PWV). Laboratory data were shown in safety data. A random-effect model was used to provide the summary measures of effect [standardised mean difference (SMD) and 95% confidence interval (CI)].

Results: Seven randomised, controlled trials and one nonrandomised, controlled trial involving 370 patients were included. Six studies reported that the progression of CACS or AACS was slower in the intravenous STS group compared with the control group (SMD -3.24, 95% CI: -5.29, -1.18, p = 0.002). Two studies showed the increase in PWV was less in the STS group compared with the control group (SMD -0.52, 95% CI: -0.92, -0.13, p = 0.009). During the trial period, a lower high-sensitivity C-reactive protein level (SMD 1.61, 95% CI: 0.19, 3.04, p = 0.03), a decrease in serum bicarbonate level (SMD 0.67, 95% CI: 0.22, 1.11, p = 0.003) and an increase in serum phosphate level (SMD -0.32, 95% CI: -0.62, -0.03, p = 0.03) were noted in the intravenous STS group compared with the control group. However, serum calcium and parathyroid hormone levels showed no difference between the two groups after the trials. The most common adverse events were temporary nausea and vomiting, which occurred in 12.5 to 75% of patients.

Conclusions: Intravenous STS may slow down the progression of vascular calcification and ameliorate arterial stiffness in dialysis patients. Reliably defining the efficacy and safety of intravenous STS in attenuating the progression of vascular calcification requires a high-quality trial with a large sample size.

Background: Renal denervation (RDN) is an interventional treatment for patients with uncontrolled hypertension. The Global SYMPLICITY Registry (GSR) is a prospective, all-comer, world-wide registry designed to assess the safety and efficacy of RDN. We evaluated the outcomes in South African patients in the GSR over 12 months.

Methods: Eligible patients with hypertension had a daytime mean blood pressure (BP) > 135/85 mmHg or night-time mean BP > 120/70 mmHg. Office and 24-hour ambulatory systolic BP reduction and adverse events over 12 months were evaluated.

Results: South African patients (n = 36) in the GSR had a mean age of 54.4 ± 9.9 years with a median of four prescribed antihypertensive medication classes. At 12 months, mean changes in office and 24-hour ambulatory systolic BP were -16.9 ± 24.2 and -15.3 ± 18.5 mmHg, respectively, with only one adverse event recorded.

Conclusions: RDN safety and efficacy in South African patients were consistent with world-wide GSR results.

Background: In clinical practice, left ventricular hypertrophy (LVH) is defined by physical findings and electrocardiographic criteria, which are useful but imperfect tools, echocardiographic criteria and cardiac magnetic resonance imaging. In echocardiography, LVH is defined not by left ventricular wall thicknesses but by left ventricular mass. The latter is calculated according to Devereux's formula, and is increased by insulin resistance/hyperinsulinaemia. It is however unclear whether insulin resistance, hyperinsulinaemia, or both, is actually causative and what their collective or individual influence is on the components of Devereux's formula and parameters of left ventricular diastolic function. This study evaluated the associations of the homeostatic model assessment for insulin resistance (HOMAIR) and fasting plasma insulin levels with components of Devereux's formula and parameters of left ventricular diastolic function.

Methods: Relevant clinical data were collected from 220 hypertensive patients recruited between January and December 2019. The associations of components of Devereux's formula and parameters of diastolic function with insulin resistance were tested using binary ordinal, conditional and classical logistic regression models.

Results: Thirty-two (14.5%) patients (43.9 ± 9.1 years), 99 (45%) patients (52.4 ± 8.7 years) and 89 (40.5%) patients (53.1 ± 9.8 years) had normal left ventricular geometry, concentric left ventricular remodelling and concentric left ventricular hypertrophy, respectively. In multivariable adjusted analysis, 46.8% of variation in interventricular septum diameter (R^² = 0.468; overall p = 0.001) and 30.9% of E-wave deceleration time (R^² = 0.309; overall p = 0.003) were explained by insulin level and HOMAIR, 30.1% of variation in left ventricular end-diastolic diameter (R^² = 0.301; p = 0.013) by HOMAIR alone, and 46.3% of posterior wall thickness (R^² = 0.463; p = 0.002) and 29.4% of relative wall thickness (R^² = 0.294; p = 0.007) by insulin level alone.

Conclusions: Insulin resistance and hyperinsulinaemia did not have the same influence on the components of Devereux's formula. Insulin resistance appeared to act on left ventricular end-diastolic diameter, while hyperinsulinaemia affected the posterior wall thickness. Both abnormalities acted on the interventricular septum and contributed to diastolic dysfunction via the E-wave deceleration time.

Background: In the current guidelines, dual antiplatelet therapy [acetylsalicylic acid (ASA) + clopidogrel] is recommended for at least three months after peripheral iliac stenting. In this study, we investigated the effect on clinical outcomes of adding ASA in different doses and at different times after peripheral revascularisation.

Methods: Seventy-one patients were administered dual antiplatelet therapy after successful iliac stenting. Group 1, consisting of 40 patients, was given 75 mg of clopidogrel plus 75 mg of ASA in a single dose in the morning. In group 2, separate doses of 75 mg of clopidogrel (in the morning) and 81 mg of 1 × 1 ASA (in the evening) were started in 31 patients. The demographic data and bleeding rates of the patients after the procedure were recorded.

Results: The groups were found to be similar in terms of age, gender and accompanying co-morbid factors (p > 0.05). The patency rate was 100% in the first month in both groups, and it was above 90% at the sixth month. When one-year patency rates were compared, although the first group had higher rates (85.3%), no significant difference was found (p < 0.05). However, there were 10 (24.4%) bleeding events in group 1, and five (12.2%) of these were in the gastrointestinal system, resulting in reduced haemoglobin levels (p = 0.038).

Conclusion: ASA doses of 75 mg or 81 mg did not affect one-year patency rates. However, higher bleeding rates were observed in the group that received both clopidogrel and ASA treatment simultaneously (in the morning) despite the lower dose of ASA.

Aim: The impact of the COVID-19 pandemic on cardiology fellowship training in sub-Saharan Africa (SSA) is not known. This study aimed to determine the impact of the COVID-19 pandemic on fellowship training, and reviewed the adaptiveness of the existing training systems.

Methods: We conducted a three-month data survey related to the cardiology fellows' clinical exposure at the Aga Khan University Hospital, Kenya, before the COVID-19 pandemic and compared it with a three-month period during the pandemic. Hospital data volumes for patients' contacts, ambulatory and catheterisation laboratory procedures recorded during the periods of March to May 2019 (three-months pre-COVID-19) and March to May 2020 (three-months during the COVID-19 pandemic) were analysed. A comparative fellows' logbook evaluation of recorded cases was also conducted for the two study time periods. In addition, fellows answered a survey questionnaire related to their roles and responsibilities in the hospital, their views on cardiology training during the COVID-19 pandemic and the pandemic's impact on their training.

Results: There was a significant reduction in the volume of patients and cardiac procedures during the COVID-19 period compared to the pre-COVID-19 period. In the same line, the number of fellows' training episodes reduced significantly during the COVID-19 pandemic compared to their performances before the pandemic. Fellows felt that the COVID-19 crisis has had a moderate to severe impact on their fellowship training. They however noted an increase in the provision of virtual local and international meetings and conferences, which supported the training positively.

Conclusion: This study showed that the COVID-19 crisis resulted in a significant reduction in the total volume of patients and cardiac procedures and, in turn, the number of training episodes. This may have limited the fellows from achieving a great amount of skills base in highly technical skills by the end of their training. Opportunities for post-fellowship training in the form of continued mentorship and proctorship would be a valuable option for the trainees if there is a similar pandemic in the future.