The inaugural meeting of the Africa Heart Rhythm Association (AFHRA)

Cardiorhythm Africa, the inaugural conference of AFHRA, was conceived during the biennial PASCAR congress held in Johannesburg in November 2019, with the ambition to be the largest ever pan-African conference focused purely on arrhythmia. Significant aims were to (1) bring together arrhythmia specialists from across Africa and from the diaspora; and (2) announce the newly formed African Heart Rhythm Association (AFHRA), an affiliate organisation of PASCAR formed from the amalgamation of the Cardiac Pacing and Arrhythmias taskforces. The meeting held in Nairobi (29­31 January 2020) was organised to provide a focus on resource-constrained arrhythmia management within the African context and novel/advanced and potentially home-grown solutions. There was full representation from all five PASCAR regions (North, East, West, Central and Southern Africa). This report summarises the scope and perspective of the first Cardiorhythm Africa meeting and presents the future directions for this annual meeting

Ultrasound molecular imaging of arterial thrombi with novel microbubbles modified by cyclic RGD in vitro and in vivo.

Despite immense potential, ultrasound molecular imaging (UMI) of arterial thrombi remains very challenging because the high-shear arterial flow limits binding of site-targeted microbubbles to the thrombi. The linear Arg-Gly-Asp (RGD) peptides have been successfully applied to evaluate venous, atrial, and arteriolar thrombi, but have thus far failed in the detection of arterial thrombi. Cyclic RGD (Arg-Gly-Asp-D-Phe-Cys) is a cyclic conformation of linear RGD peptides, which has much higher binding-affinity and selectivity for binding to the glycoprotein (GP) IIb/IIIa receptor than its linear counterpart and thus is likely to be an optimal targeted molecular probe for ultrasound molecular imaging of arterial thrombi. In this study, we sought to assess the feasibility of a novel microbubble conjugated with cyclic RGD (Mb-cyclic RGD) in UMI of arterial thrombi in vitro and in vivo . As expected, Mb-cyclic RGD had greater GP IIb/IIIa-targeted binding capability in all shear stress conditions. In addition, the shear stress at half-maximal detachment of Mb-cyclic RGD was 5.7-fold higher than that of microbubbles with non-specific peptide (Mb-CON) (p<0.05). Mb-cyclic RGD enhanced the echogenicity of the platelet-rich thrombus in vitro whereas Mb-CON did not produce enhancement. In the in vivo setting, optimal signal enhancement of the abdominal aortic thrombus was displayed with Mb-cyclic RGD in all cases. Mean video intensity of the abdominal aortic thrombi with Mb-cyclic RGD was 3.2-fold higher than that with Mb-CON (p<0.05). The novel Mb-cyclic RGD facilitated excellent visualisation of arterial thrombi using UMI and showed great promise for clinical applications.

Effect of obstructive sleep apnea syndrome on serum C-reactive protein level, left atrial size and premature atrial contraction / 南方医科大学学报

<p><b>OBJECTIVE</b>To assess the changes of serum C-reactive protein (CRP) level, left atrial size and atrial premature contraction (PAC) in patients with obstructive sleep apnea syndrome (OSAS).</p><p><b>METHODS</b>This study involved 277 patients with OSAS diagnosed after an overnight polysomnography, who underwent a 24-h Holter electrocardiography and ambulatory blood pressure monitoring for detection of PAC. According to the apnea-hypopnea index (AHI), 137 patients with PAC identified from these patients were classified into 3 groups, namely the mild (5≥AHI<15), moderate (15≥AHI<30) and severe (AHI≥30) groups. Serum CRP level was assessed by a high-sensitivity radio-immunoassay. The left atrial diameter and echocardiographic parameters were recorded by transthoracic Doppler echocardiography (TTE).</p><p><b>RESULTS</b>We found a high prevalence of PAC in these OSAS patients (137/277, 49.4%). Serum CRP was significantly higher in severe OSAS group (5.01∓4.68 mg/L) than in the moderate (3.03∓1.94 mg/L) and mild OSAS (2.98∓1.82 mg/L) groups (P=0.040 and 0.033, respectively). The left atrial diameter was significantly increased in severe OSAS group (40.1∓7.9 mm) as compared to that in moderate (37.9∓5.5 mm) and mild (33.7 ∓ 3.8 mm) groups (P=0.025 and 0.002, respectively). The severity of OSAS was positively correlated to both CRP (r=0.304, P=0.034) and left atrial diameter (r=0.411, P=0.003). After adjusting for gender, age and body mass index (BMI), a strong correlation was found between the left atrial diameter and CRP (r=0.594, P=0.0005).</p><p><b>CONCLUSION</b>There is a high prevalence of PAC in OSAS patients. The progression of OSAS is associated with increased serum CRP level and left atrial size in patients with premature atrial complexes. Our study suggests that inflammation associated with OSAS might contribute to atrial structural and electrical remodeling in OSAS patients with PAC.</p>

Comparison of eight equations for estimating glomerular filtration rate in patients with cardiovascular diseases / 南方医科大学学报

<p><b>OBJECTIVE</b>To assess the diagnostic value of 8 equations using different variables for determining the estimated glomerular filtration rate (eGFR) in patients with cardiovascular diseases.</p><p><b>METHODS</b>GFR was estimated in 208 patients with cardiovascular diseases by (99m)Tc-DTPA dynamic renal imaging, and the eGFR was derived from 8 equations using different variables.</p><p><b>RESULTS</b>In patients with chronic kidney disease (CKD) stages 1-3, the eGFR calculated suing serum creatinine (SCr)-based equation was better correlated to GFR estimated by (99m)Tc-DTPA renal imaging than that derived from cystatin C (Cys C)-based equations, whereas in patients with CKD stages 4 and 5, the estimates by the latter equation showed a better correlation to GFR. Compared with (99m)Tc-DTPA renal imaging, MDRD-based equation and simple MDRD equation resulted in a higher eGFR in patients with CKD stages 4 and 5, the Rule equation had a lower eGFR in CKD stages 1 and 2, the Macisaac equation yielded a higher eGFR in CKD stages 2-5, and the Tan equation showed a higher eGFR in CKD stages 2 and 3. In patients with mild renal dysfunction, the Scr-based equation had a higher AUC(ROC) than Cys C-based equation, which was reversed in patients with severe renal dysfunction; the AUC(ROC) of the two equations were comparable in patients with moderate renal dysfunction. Compared with (99m)Tc-DTPA renal imaging, the modified MDRD equation and Arnal-Dade equation showed no significant difference in the eGFR in patients with CKD stages 1-5.</p><p><b>CONCLUSION</b>Modified MDRD equation (or simple MDRD equation) and Arnal-Dade equation are superior to other calculation methods for estimating the GFR in Chinese patients with cardiovascular disease.</p>

Management of subacute myocardial infarction in a patient with left coronary artery originating from the right coronary artery / 南方医科大学学报

Although the majority of coronary artery anomalies are found incidentally and not clinically significant, the interarterial course between the major vessels of the aberrant artery may be responsible for syncope, angina, arrhythmias or sudden death. There are only a few case reports describing the origination of all the coronary arteries from a single ostium. This anomaly occurs in only 0.024%-0.044% of the population. Left coronary artery originating from the right coronary is a rare coronary abnormality. Here we report a case of acute myocardial infarction in a patient with anomalous left coronary artery originating from the right coronary artery, as was confirmed by computerized tomography angiogram, which showed that only one single coronary artery stem originating from the right sinus of Valsalva trifurcated into a right coronary artery, left circumflex artery and a hypoplastic left anterior descending artery. Subsequent percutaneous coronary intervention (PCI) procedures were performed successfully. PCI procedures should be carried out with great caution in such cases, and this condition should be managed as a left main lesion.