Evaluation of Myocardial Perfusion Classification for Interventional Treatment of Chronic Total Occlusion of Coronary Artery / 中山大学学报(医学科学版)

【Subjects】 To investigate the clinical application value of myocardial contrast echocardiography （MCE） in selecting CTO-PCI patients. MethodsFrom February 2019 to March 2020， a total of 50 patients with chronic coronary artery occlusion were consecutively selected as the research subjects. MCE and two-dimensional speck-tracking echocardiography were completed before and 12 months after interventional therapy. The primary end point was major adverse cardiovascular events. Patients were divided into groups according to the preoperative myocardial perfusion level of MCE. The improvement of left ventricular function was evaluated by two-dimensional echocardiography and left ventricular global longitudinal strain. ResultsCompared with the abnormal perfusion group， the improvement of GLS in the normal perfusion group was greater （P=0.028）. The wall motion score index （WMSI） of the abnormal perfusion group before PCI was higher than that of the normal perfusion group （P=0.002）. WMSI in the abnormal perfusion group was higher than that in the normal perfusion group one year after PCI （P<0.001）. The left ventricular GLS（P=0.008）.WMSI（P=0.016） and left ventricular end-diastolic volume（P=0.032） in the normal perfusion group were improved compared with those before operation； The postoperative perfusion score of patients with abnormal perfusion was significantly improved （ P=0.032）. ConclusionMCE has clinical application value in optimizing the selection of CTO-PCI patients. CTO patients with different myocardial perfusion types have different benefits after PCI.

Right ventricular outflow tract septal pacing versus apical pacing: A prospective, randomized, single-blind 5-years follow-up study of ventricular lead performance and safety / 华中科技大学学报（医学）（英德文版）

Lead placement for ventricular pacing variably impacts the physiological benefit of the patient. This study evaluated the ventricular lead performance and safety of right ventricular outflow tract septal pacing in patients with bradyarrhythmia in South China over 60-month follow-up. Totally, 192 patients (108 males, and 84 females, 63±21 years old) with bradyarrhythmia were randomly divided into two groups. The right ventricular outflow tract septum (RVOTs) group had lead placement near the septum (n=97), while the right ventricular apex (RVA) group had a traditional apical placement (n=95). RV septal lead positioning was achieved with a specialized stylet and confirmed using fluoroscopic projection. All patients were followed up for 60 months. Follow-up assessment included stimulation threshold, R-wave sensing, lead impedance and lead complications. The time of electrode implantation in both the ROVTs and RVA groups were significantly different (4.29±0.61 vs. 2.16±0.22 min; P=0.009). No differences were identified in threshold, impedance or R-wave sensing between the two groups at 1st, 12th, 36th and 60th month during the follow-up period. No occurrence of electrode displacement, increased pacing threshold or inadequate sensing was found. The long-term active fixation ventricular electrode performance in RVOTs group was similar to that in RVA group. RVOTs pacing near the septum using active fixation electrodes may provide stability during long-term follow-up period.

Impact of CYP2C9 and VKORC1 polymorphism on warfarin response during initiation of therapy / 中华心血管病杂志

<p><b>OBJECTIVE</b>To investigate potential contributions of genetic variants of cytochrome P-450 2C9 (CYP2C9) and vitamin K expoxide reductase (VKORC1) to the anticoagulation response during the initiation of warfarin therapy in the Han Chinese population.</p><p><b>METHODS</b>A total of 798 Han Chinese patients received long-term warfarin anticoagulant therapy orally after valve replacement in our hospital between 2000 and 2008 were included in this study. Nine single nucleotide polymorphism (SNP) loci [rs12572351 G > A, rs9332146 G > A, rs4917639 G > T, rs1057910 A > C (CYP2C9(*)3), rs1934967 G > T, rs1934968 G > A, rs9923231 C > T (VKORC1-1639 G > A), rs2359612 G > A and rs10871454 C > T] in 2 genes including CYP2C9 and VKORC1, which were possibly correlated with warfarin pharmacokinetics and pharmacodynamics through literature retrieval, were selected and analyzed. Warfarin steady-state dose requirement, time to the INR (the international normalized ratio) within the therapeutic range and percent of the INR of more than 3.5 were compared among genotype subgroups. SNaPshot technique was used to detect gene SNPs; Hardy-Weinberg genetic equilibrium test was used to test population representativeness.</p><p><b>RESULTS</b>CYP2C9(*)3 genotype did not affect the required warfarin dose while it was associated with increased risk of bleeding when treated with routine dosage regimen during the initiation of treatment. The allelic mutation frequency at VKORC1 gene rs10871454G > A and VKORC1-1639G > A SNP loci was 92.04% and 88.03%, respectively and rs10871454 was in perfect linkage disequilibrium with-1639. Patients with VKORC1 rs10871454 genetic mutation required lower warfarin dose in the first 28 days of therapy. VKORC1-1639 genetic polymorphism was also associated with shorter time to the INR within the therapeutic range and increased risk of over-anticoagulation.</p><p><b>CONCLUSION</b>Detecting genetic polymorphism of CYP2C9 and VKORC1 could guide clinical use of warfarin to reduce the risk of adverse reactions including bleeding in patients receiving chronic anticoagulation therapy.</p>

Clinical application of anticoagulation treatment with warfarin after prosthetic heart valve replacement: a single center-based survey / 南方医科大学学报

<p><b>OBJECTIVE</b>To investigate the clinical application of anticoagulation treatment with warfarin after prosthetic heart valve replacement and compare the effect and safety of different anticoagulant intensities.</p><p><b>METHODS</b>A total of 845 Chinese patients receiving oral warfarin for anticoagulant treatment after prosthetic heart valve replacement in Guangdong General Hospital between 2000 and 2008 were enrolled in this survey. The general data, clinical data, medications, international normalized ratio (INR) and results of echocardiogram of these patients were followed up to observe the incidence of complication of thrombo-embolism and such adverse effect as hemorrhage.</p><p><b>RESULTS</b>All the patients were of Han nationality, and Cantonese accounted for 88.04%. The daily mean maintenance dose of warfarin was 2.92∓0.88 mg in these patients with a median INR of 2.09∓0.39. Of these patients, 44.62% received low-intensity anticoagulant treatment with warfarin with the INR maintained between 1.5 and 2.0, and 56.45% had standard anticoagulant intensity with the INR maintained between 2.0 and 3.0. The total incidence of thrombo-embolism was 4.14%. Severe hemorrhage occurred in 14 cases (1.66%), most frequently in the alimentary tract. The events of hemorrhage were correlated to the type of prosthetic heart valve replacement, occurring more frequently in patients with mechanical prosthetic heart valve replacement than in those with biological ones. No significant difference was found in the incidence of thrombo-embolism and server hemorrhage between the two groups receiving low and standard intensity therapy anticoagulant.</p><p><b>CONCLUSION</b>The effect and safety of low-intensity anticoagulant treatment are comparable to that of standard intensity treatment in Chinese Han patients, and anticoagulation treatment with warfarin is effective and safe to maintain the INR between 1.8-3.0.</p>

Left atrial size and function after radiofrequency catheter ablation for paroxysmal atrial fibrillation / 中华心血管病杂志

<p><b>OBJECTIVE</b>To evaluate the impact of radiofrequency catheter ablation on left atrial (LA) size and function in patients with paroxysmal atrial fibrillation (PAF) and whether there is any difference between segmental pulmonary vein ostial isolation (SPVI) and circumferential pulmonary vein ablation (CPVA).</p><p><b>METHODS</b>Sixty-six patients with highly symptomatic atrial fibrillation were assigned to undergo either SPVI or CPVA. Transthorax echocardiography was performed before, 1 day, 1 months and 3 months after the procedure. LA dimension, LA area, late diastolic peak velocity of mitral valve inflow (A) and peak atrial systolic mitral annulus velocity (A') were recorded.</p><p><b>RESULTS</b>Of 66 consecutive patients with symptomatic PAF, 30 patients underwent SPVI and 36 underwent CPVA. After a mean follow-up of (315 +/- 153) days, 21 patients (70%) after SPVI and 28 patients (75%) after CPVA were free of atrial tachyarrhythmia. As compared with the baseline, LA area decreased at 1-month after ablation in SPVI group and at 3-month in CPVA group. LA dimension decreased also in SPVI group, but did not in CPVA group. A velocity and A' velocity declined remarkably 1 day after CPVA, and restored 3 months later. The former went back to the level of baseline, and the latter exceeded it apparently. In SPVI group, A velocity increased at 1-month, and maintained in 3-month after ablation. A' velocity increased at 3-month after ablation. No reduction of A velocity or A' velocity was found after SPVI.</p><p><b>CONCLUSIONS</b>This study demonstrated a decrease in LA area and an improvement in LA systolic function 3 months after ablation for PAF. The LA damage by CPVA was more than that by SPVI, which was characterized by the reduction of LA function 1 day after procedure and the delayed improvement of LA size and functional parameters.</p>

Thoracic aorta echocardiographic features of patients with bicuspid aortic valve / 中华心血管病杂志

<p><b>OBJECTIVE</b>To observe the thoracic aorta features in patients with bicuspid aortic valve (BAV) with echocardiography.</p><p><b>METHODS</b>We retrospectively analyzed the echocardiographic features and clinical manifestations in 273 patients with BAV detected from 1991-04 to 2006-02.</p><p><b>RESULTS</b>(1) Aortic dimensions of the anulus, the sinuses of valsalva, the sinotubular junction, the ascending aorta at the level of its largest diameter of 31 patients with functionally normal BAV were significantly increased compared that in control subjects (P < 0.01 to P < 0.001) while the dimension of the descending aorta posterior to the left atrium was similar between the two groups (P > 0.05). (2) There is no relation between the vulval positions of BAV and aortic dimensions (P > 0.05). (3) The dimensions of the annulus as well as the sinuses of valsalva were negatively related to the aortic valve gradient, and the dimension of the annulus, the sinuses of valsalva and sinotubular junction were positively related to the degree of aortic regurgitation in 273 patients with BAV (all P < 0.05).</p><p><b>CONCLUSION</b>Our results show there is a hemodynamic independent thoracic aortic dilation in patients with functionally normal BAV. Gradient and aortic regurgitation are related to the dimension of the annulus, the sinuses of valsalva and sinotubular junction in patients with BAV.</p>

Real-time three-dimensional myocardial contrast echocardiography in assessment of myocardial perfusion defects / 中华医学杂志(英文版)

<p><b>BACKGROUND</b>Both real-time three-dimensional echocardiography (RT3DE) and myocardial contrast echocardiography (MCE) are novel imaging techniques. The purpose of this study was to confirm the feasibility and accuracy of RT3DE combined with MCE for quantitative evaluation of myocardial perfusion defects.</p><p><b>METHODS</b>Thirteen dogs underwent ligation of the left anterior descending artery (LAD, n = 6) or distal branch of the left circumflex artery (LCX, n = 7) under general anaesthesia. Three to four ml of a perfluoropropane (C3F8) microbubble contrast agent was injected intravenously to assess the resulting myocardial perfusion defects with a commercially available Philips SONOS-7500 ultrasound system. After removal of the dog hearts, Evans blue dye was injected via the left and right coronary arteries to stain the myocardium at risk. In vitro anatomic measurements of myocardial mass after removal of the animals' hearts were used as controls.</p><p><b>RESULTS</b>Left ventricular (LV) mass determined by RT3DE ranged 36.7 - 68.9 g [mean, (54.6 +/- 9.6) g] before coronary artery ligation, and correlated highly (r = 0.99) with in vitro measurement of LV mass [range, 38.9 - 71.1 g; mean, (55.6 +/- 9.3) g]. There was no significant difference between RT3DE and in vitro measurements of LV mass [range, 36.7 - 68.9 g; mean, (51.3 +/- 12.5) g. Or range, 38.9 - 71.1 g; mean, (53.7 +/- 12.3) g, respectively] and under-perfused mass [range, 0 - 21.4 g; mean, (12.0 +/- 6.9) g. Or range, 0 - 19.8 g; mean, (10.8 +/- 6.3) g, respectively] after the LAD ligation (P > 0.05). Likewise, no significant difference was present between RT3DE and in vitro measurements of LV mass [range, 50.1 - 65.4 g; mean, (57.5 +/- 5.9) g. Or range, 51.5 - 65.8 g; mean, (57.3 +/- 6.4) g, respectively] and under-perfused mass [range, 0 - 25.6 g; mean, (13.3 +/- 9.6) g. Or range, 0 - 22.7 g; mean, (12.8 +/- 8.1) g, respectively] after the LCX ligation (P > 0.05). For all the animals with coronary ligation, LV mass measured by RT3DE ranged 35.9 - 68.6 g [mean, (54.8 +/- 10.0) g] and there was no significant difference between RT3DE and in vitro measurements of LV mass and under-perfused mass (P > 0.05, r = 0.99). Further, the under-perfused mass derived from RT3DE [range, 0 - 25.6 g; mean, (12.7 +/- 8.2) g] correlated strongly with the in vitro measurements [range, 0 - 22.7 g; mean, (11.9 +/- 7.2) g] (r = 0.96).</p><p><b>CONCLUSION</b>RT3DE with MCE is a rapid and accurate method for estimating LV myocardial mass and quantifying perfusion defects.</p>

Real-time three-dimensional echocardiography for quantifying left ventricular mass / 中国医学科学杂志(英文版)

<p><b>OBJECTIVE</b>To test the accuracy of real-time three-dimensional echocardiography (RT3DE) imaging system for evaluating left ventricular mass (LVM) in phantom and excised canine heart.</p><p><b>METHODS</b>Ten left ventricular (LV) wall phantoms made of two rubber-bursas, ten excised canine hearts underwent RT3DE and two-dimensional echocardiography (2DE). In RT3DE "full volume" imaging, the myocardial volume was measured using 2, 4, 8, and 16-plane method with the analysis software of RT3DE. Mass was then calculated by multiplying the resulting myocardial volume by specific density of myocardial tissue. In 2DE the masses were measured by area-length method. The true LV wall phantom mass was measured by water displacement and the canine LVM was weighed by anatomy, which served as a reference standard. We compared RT3DE or 2DE with true mass.</p><p><b>RESULTS</b>In LV wall phantoms, RT3DE correlated with true masses strongly (r = 0.813-0.994) and weakly correlated between 2DE and true masses (r = 0.628). In excised canine hearts, there is an excellent correlation between RT3DE and true masses (r = 0.764-0.991), while 2DE value showed a lesser correlation (r = 0.514). There are no difference between RT-3DE and true masses (P > 0.05) but different between 2DE and true masses (P < 0.05). In different planes, there was no difference between 8-plane and 16-plane (P > 0.05) but different between 8-plane and 2, 4-plane (P < 0.05).</p><p><b>CONCLUSION</b>RT3DE can accurately quantify LVM and provide a new tool to evaluate LV function. For LVM by RT3DE, 8-plane measurement method is the best choice for accuracy and convenience.</p>

Validation of real-time three-dimensional echocardiography for quantifying left and right ventricular volumes: an experimental study / 中华医学杂志(英文版)

<p><b>BACKGROUND</b>Assessment of the left ventricular (LV) and the right ventricular (RV) volumes and their functions is important for prognostic prediction and clinical decision making. We compared the accuracy for quantifying the LV and the RV volumes in vitro between conventional two-dimensional echocardiography (2DE) and real-time three-dimensional echocardiography (RT3DE).</p><p><b>METHODS</b>The volumes of 37 rubber-models (10 regularly shaped to simulate normal LV, 7 shaped to simulate LV with symmetric aneurysm, 8 shaped to simulate LV with asymmetric aneurysm, and 12 irregularly shaped to simulate normal RV) and 10 excised canine hearts were measured by RT3DE and 2DE. On RT3DE "full volume" imaging, the inner-surfaces of the rubber-models and canine LV and RV were outlined and the volumes were measured using 2-, 4-, 8- and 16-plane methods with the RT3DE analysis software. On 2DE imaging, the volumes were measured by the Simpson method. The LV and RV volumes measured by drained water were served as reference values, with which we compared RT3DE and 2DE data.</p><p><b>RESULTS</b>In rubber models mimicking normal LV and LV with symmetric aneurysms, RT3DE results were strongly correlated with reference values (r = 0.795 - 0.998) and there was a good correlation between 2DE estimates and reference values (r = 0.715 - 0.729). There were no significant differences between RT3DE estimates, 2DE results and reference values (P > 0.05). In rubber models mimicking the RV and LV with asymmetric aneurysm, RT3DE strongly correlated with reference values (r = 0.765 - 0.988), but 2DE weakly correlated with reference values (r = 0.518 - 0.592). There were no differences between RT3DE and reference values (P > 0.05), but a significant difference between 2DE and reference values occurred (P < 0.05). For excised canine hearts, there was a strong correlation between RT3DE and reference values (r = 0.728 - 0.914), while 2DE showed a less obvious correlation (r = 0.502 - 0.615). Again, there were no significant differences between RT3DE and reference values (P > 0.05), but there was a significant difference between 2DE and reference values (P < 0.05).</p><p><b>CONCLUSIONS</b>RT3DE can accurately quantify LV and RV volumes and provides a new tool to evaluate LV and RV function. For LV and RV measurements by RT3DE, 8-plane strategy is the optimum choice for accuracy and convenience.</p>