Improving cardiovascular outcomes for patients with heart failure in sub-Saharan Africa: conference proceedings of the 2022 Nigerian Cardiovascular Symposium.

The Nigerian Cardiovascular Symposium is an annual conference held in partnership with cardiologists in Nigeria and the diaspora to provide updates in cardiovascular medicine and cardiothoracic surgery with the aim of optimising cardiovascular care for the Nigerian population. This virtual conference (due to the COVID-19 pandemic) has created an opportunity for effective capacity building of the Nigerian cardiology workforce. The objective of the conference was for experts to provide updates on current trends, clinical trials and innovations in heart failure, selected cardiomyopathies such as hypertrophic cardiomyopathy and cardiac amyloidosis, pulmonary hypertension, cardiogenic shock, left ventricular assist devices and heart transplantation. Furthermore, the conference aimed to equip the Nigerian cardiovascular workforce with skills and knowledge to optimise the delivery of effective cardiovascular care, with the hope of curbing 'medical tourism' and the current 'brain drain' in Nigeria. Challenges to optimal cardiovascular care in Nigeria include workforce shortage, limited capacity of intensive care units, and availability of medications. This partnership represents a key first step in addressing these challenges. Future action items include enhanced collaboration between cardiologists in Nigeria and the diaspora, advancing participation and enrollment of African patients in global heart failure clinical trials, and the urgent need to develop heart failure clinical practice guidelines for Nigerian patients.

Severe isolated aortic stenosis with normal left ventricular systolic function and low transvalvular gradients: pathophysiologic and prognostic insights.

BACKGROUND AND AIM OF THE STUDY: A significant proportion of patients with severe valvular aortic stenosis (AS) and preserved left ventricular (LV) systolic function have low transvalvular gradients. The study aim was to determine the mechanisms and outcome of patients with this hemodynamic profile of AS. METHODS: Among 1,679 patients who underwent transthoracic echocardiography for the evaluation of AS at the authors' institution, 215 (105 females, 110 males; mean age: 77 +/- 10 years) had isolated AS (mean aortic valve area index 0.39 +/- 0.1 cm2/m2), normal sinus rhythm and normal LV ejection fraction. The mean follow up was 23 +/- 12 months, and the end-points were mortality, aortic valve replacement (AVR), or mortality or AVR. RESULTS: Forty-seven patients had a transvalvular mean gradient (MG) <30 mmHg (MG(low)) and 168 had MG > or = 30 mmHg (MG(high)). Compared to MG(high), the MG(low) group had a higher prevalence of hypertension, lower LV end-diastolic volume index (47 +/- 9 versus 56 +/- 12 ml/m2, p <0.0001), lower LV stroke vol-ume index (37 +/- 12 versus 41 +/- 11 ml/beat, p <0.0002), a lesser severity of stenosis (aortic valve area index 0.37 +/- 0.09 versus 0.46 +/- 0.09 cm2/m2, p <0.0001) and a higher systemic vascular resistance (2163 +/- 754 versus 1879 +/- 528 dyne cm s(-5). The LV end-diastolic volume index, systemic vascular resistance and energy loss index were predictors of MG <30 mmHg (OR = 0.30, 95% CI, 0.12, 0.62; OR = 3.05, 95% CI, 1.71, 6.26; and OR = 6.76, 95% CI, 3.44,15.38, respectively). MG <30 mmHg (MGhigh) was associated with almost 50% lower referral to surgery and a two-fold increase in preoperative mortality. CONCLUSION: In severe AS with a normal LV ejection fraction, MG <30 mmHg is related to a lesser severity of stenosis, a smaller LV volume, a lower flow rate and a higher systemic vascular resistance. Compared to the MG(high) group, these patients were less frequently referred to surgery and had a higher mortality.

Comparison of Brachial Vein Versus Internal Jugular Vein Approach for Access to the Right Side of the Heart With or Without Myocardial Biopsy.

Right heart catheterization (RHC) and endomyocardial biopsy are mainstay procedures for patients with heart failure and heart transplantation. Approaches are predominantly neck (internal jugular) or leg (femoral vein). We describe a novel arm (brachial/basilica vein) approach. Over 5.5 years, 1,130 right-sided cardiac procedures in 276 patients were analyzed retrospectively and divided into either neck or arm approach. Comparative analyses of procedural success, time, safety, efficacy, and cost were performed. Patient preference was assessed for those who had both neck and arm approaches. In patients receiving RHC (174 neck and 121 arm cases) and in those receiving RHC + biopsy (594 neck and 141 arm cases), mean elapsed and fluoroscopic times (minutes), respectively, were 60 ± 20 versus 62 ± 19 and 3.43 ± 3.8 versus 4.99 ± 5.2 (RHC neck vs arm, respectively), and 55 ± 19 versus 63 ± 17 and 4.14 ± 3.4 versus 5.22 ± 2.6 (RHC + biopsy neck vs arm, respectively). Procedural complications were low (n = 7, 0.6%) and restricted to the neck approach. Patients surveyed preferred the arm approach. In conclusion, RHC and endomyocardial biopsy through the brachial vein can be performed safely, timely, effectively, and at equivalent cost compared with a neck approach. We advocate that an arm approach be the preferred method for these procedures.

Relative importance of errors in left ventricular quantitation by two-dimensional echocardiography: insights from three-dimensional echocardiography and cardiac magnetic resonance imaging.

BACKGROUND: The accuracy of left ventricular (LV) volumes and ejection fraction (EF) on two-dimensional echocardiography (2DE) is limited by image position (IP), geometric assumption (GA), and boundary tracing (BT) errors. METHODS: Real-time three-dimensional echocardiography (RT3DE) and cardiac magnetic resonance imaging (CMR) were used to determine the relative contribution of each error source in normal controls (n = 35) and patients with myocardial infarctions (MIs) (n = 34). LV volumes and EFs were calculated using (1) apical biplane disk summation on 2DE (IP + GA + BT errors), (2) biplane disk summation on RT3DE (GA + BT errors), (3) 4-multiplane to 8-multiplane surface approximation on RT3DE (GA + BT errors), (4) voxel-based surface approximation on RT3DE (BT error alone) and (5) CMR. By comparing each method with CMR, the absolute and relative contributions of each error source were determined. RESULTS: IP error predominated in LV volume quantification on 2DE in normal controls, whereas GA error predominated in patients with MIs. Underestimation of volumes on 2DE was overcome by increasing the number of imaging planes on RT3DE. Although 4 equidistant image planes were acceptable, the best results were achieved with voxel-based RT3DE. For EF estimation, IP error predominated in normal controls, whereas BT error predominated in patients with MIs. Nevertheless, one third of the EF estimation error in patients with MIs was due to a combination of IP and GA errors, both of which may be addressed using RT3DE. CONCLUSIONS: The relative contribution of each source of LV quantitation error on 2DE was defined and quantified. Each source of error differed depending on patient characteristics and LV geometry.

Normal values of right ventricular size and function by real-time 3-dimensional echocardiography: comparison with cardiac magnetic resonance imaging.

BACKGROUND: Assessment of right ventricular function by 2-dimensional echocardiography (2DECHO) is difficult because of its complex shape. Real-time 3-dimensional echocardiography (RT3DECHO) may be superior. METHODS: End-diastolic volume, end-systolic volume, stroke volume, and ejection fraction obtained by 2DECHO, RT3DECHO short-axis disk summation (DS), and RT3DECHO apical rotation were compared with cardiac magnetic resonance imaging in 71 healthy individuals. RESULTS: RT3DECHO DS showed less volume underestimation compared with 2DECHO and RT3DECHO apical rotation. Test-retest variability for RT3DECHO DS end-diastolic volume, end-systolic volume, stroke volume, and ejection fraction were 3.3%, 8.7%, 10%, and 10.3%, respectively. Normal reference ranges of indexed volumes (mean +/- 2SD) for right ventricular end-diastolic volume, end-systolic volume, stroke volume, and ejection fraction were 38.6 to 92.2 mL/m(2), 7.8 to 50.6 mL/m(2), 22.5 to 42.9 mL/m(2), and 38.0% to 65.3%, respectively, for women and 47.0 to 100 mL/m(2), 23.0 to 52.6 mL/m(2), 14.2 to 48.4 mL/m(2), and 29.9% to 58.4%, respectively, for men. CONCLUSIONS: RT3DECHO DS is superior to RT3DECHO apical rotation and 2DECHO for right ventricular quantification, and performs acceptably when compared with cardiac magnetic resonance imaging in healthy individuals.