Relationship between Tpeak-Tend interval and coronary artery stenosis and effects of percutaneous transluminal coronary angioplasty on Tpeak-Tend / 南方医科大学学报

<p><b>OBJECTIVE</b>To explore the relationship between Tpeak-Tend interval (Tpe) and the extent and severity of coronary artery stenosis, and evaluate the effect of percutaneous transluminal coronary angioplasty and stent implantation (PCI) on Tpe in the patients with coronary heart disease (CHD).</p><p><b>METHODS</b>The ECG data were collected from 187 CHD patients undergoing coronary angiography and PCI to evaluate the extend and severity of coronary artery stenosis before and after the interventions.</p><p><b>RESULTS</b>The Tpe of patients with severe stenosis increased significantly as compared with that in patients with moderate stenosis (138.9-/+16.2 ms vs 116.5-/+13.7 ms, P<0.05), and a significant difference was also noted between the moderate stenosis and mild stenosis (86.4-/+12.9 ms) groups (P<0.05). The Tpe decreased significantly in the patients in the order of multi-vessel involvement (140.7-/+17.8 ms), double vessel involvement (118.6-/+14.9 ms), singly vessel involvement (100.5-/+13.2 ms), and stenosis-free (84.3-/+12.4 ms) groups (P<0.05). Tpe was correlated to the extent and severity of coronary artery stenosis (r>0.4). In patients with severe stenosis, the Tpe was significantly reduced at 1 h, 24 h, and 1 week after PCI (115.8-/+14.5, 92.7-/+12.9, and 88.2-/+11.3 ms, respectively, P<0.05).</p><p><b>CONCLUSION</b>The Tpe can reflect the severity and range of coronary artery stenosis, which can be reduced by PCI. Tpe can be a new index for evaluating myocardial ischemia in CHD patients.</p>

Clinical assessment of Tpeak-end interval for prediction of myocardial infarction / 南方医科大学学报

<p><b>OBJECTIVE</b>To assess the value of Tpeak-end interval (Tpe) in predicting myocardial infarction (MI).</p><p><b>METHODS</b>Tpe and Tpeak-end internal after correcting the heart rate (TpeRR) were measured and analyzed in 234 MI patients, who were followed-up for an average of 32 ± 10 months.</p><p><b>RESULTS</b>Clinical events occurred in 45 (19.2%) patients at the end TpeRR of the follow-up. Tpe and of the patients with clinical events were significantly higher than those in patients without the clinical events (P < 0.001). The incidence of clinical events in patients with Tpe > 140 ms were significantly higher than that in patients with Tpe ≤ 140 ms by Kaplan-Meier analysis (P < 0.001). With clinical event as the end point, the proportional hazards rate was 2.48 in univariate COX analysis (P < 0.01). After controlling for risk factors, the hazards rate was 2.66 by multvariate COX regression (P < 0.01).</p><p><b>CONCLUSION</b>Tpe is positively correlated to the prognosis of MI and serves as an new index for predicting the clinical events in MI patients.</p>

Classification of congenital ventricular defects using echocardiography for transcatheter closure / 南方医科大学学报

<p><b>OBJECTIVE</b>To determine the anatomical variation and classification of ventricular septal defect (VSD) using echocardiography for percutaneous catheter closure in eligible cases.</p><p><b>METHOD</b>The isolated ventricular septal defect was diagnosed with echocardiography in 240 patients , and 167 patients screened by transthoracic echocardiography were suitable for percutaneous catheter closure, but only 62 with isolated perimembranous VSD voluntarily received the procedure.</p><p><b>RESULTS</b>The procedure was successful in 58 patients, with a success rate of 93.5% with Amplatzer device. The diameter of VSD ranged from 2.4 to 13.9 (mean 5.3-/+2.0) mm with echocardiography, and the size of Amplatzer device ranged from 4-18 (mean 8.3-/+2.9) mm. Perimembranous ventricular septal defect was complicated by aneurysm formation in 22 patients. Residual trivial or mild shunt was seen in seven (12%) patients at 24 h and one (1.7%) patient at 3 months. Seven (12.1%) patients developed heart block, 3 (5.2%) had intermittence and transient complete heart block, and one had transient second degree atrioventricular block disappearing in 3 to 10 days, and 3 (5.2%) patients had complete right bundle branch block lasting for one month. None of the patients developed significant aortic regurgitation (P>0.05), although 22 showed a superior margin of the defect less than 3 mm from the aortic valve. The mean distance from the aortic valve was 3.7-/+2.7 (1.0 to 10.5) mm. No significant mitral and tricuspid regurgitation occurred in these patients. Four patients had unsuccessful procedures.</p><p><b>CONCLUSIONS</b>Percutaneous closure with Amplatzer device can be carried out successfully in a majority of suitable defects screened using transthoracic echocardiography. Echocardiography can exactly demonstrate the anatomical variation and classification of ventricular septal defect in adults. Attention should be given to the misdiagnosis by echocardiography of a doubly committed defect as a perimembranous outflow defect. Heart block can be an important complication of the procedure.</p>

Echocardiographic features of congenital mitral valve anomalies / 南方医科大学学报

<p><b>OBJECTIVE</b>To summarize the echocardiographic features of a wide spectrum of congenital mitral valve anomalies.</p><p><b>METHODS</b>The medical records, echocardiograms, cardiac catheterization studies, and surgical reports were reviewed. The mitral valve anomalies evaluated in the study included parachute mitral valve, double orifice mitral valve, congenital mitral stenosis with 2 papillary muscles, anomalous papillary muscle rotation, and 3 commissures and papillary muscles in 15 cases. Surgeries were performed in 11 patients, and 1 patient underwent transcatheter closure of the patent ductus arteriosus.</p><p><b>RESULTS</b>The echocardiograms of 6 cases of parachute mitral valve were characterized by a hypoplastic mitral valve with short chordal attachments to a single posterior medial papillary muscle. The mitral valve demonstrated restricted motion. The double orifice mitral valve were featured by two separate mitral valve orifice, with each suborifice supported by its own tension apparatus in 4 patients. Asymmetric hypoplastic mitral valve stenosis with two papillary muscles was found in 1 patient with short and unbalanced chordal attachments to the anterior lateral major papillary muscle. Anomalous papillary muscle rotation was found in 1 patient. Mirtal anomaly with 3 major commissures and 3 papillary muscles was found in 3 patients.</p><p><b>CONCLUSIONS</b>Echocardiography offers clear demonstration of the mitral valve thickness and chordal attachments, and allows visualization of the position and the number of the papillary muscles and interpapillary spaces for evaluation of the mobility of the valve leaflets, therefore can be a valuable diagnostic modality for congenital mitral valve anomalies, especially congenital mitral stenosis.</p>

Morphological features of congenital heart defects in en face imaging with 2-dimensional echocardiography / 南方医科大学学报

<p><b>OBJECTIVE</b>To describe the morphological features of congenital heart defects and their spatial orientations to the neighboring structures in special two-dimensional echocardiographic views.</p><p><b>METHODS</b>Conventional two-dimensional echocardiographic sections were obtained in 45 patients with atrial septal defect (ASD) and 15 with ventricular septal defect (VSD) before the en face imaging, a special echocardiographic view, was performed using a transthoracic probe for morphological characterization of the ASD and VSD. En face views of the secundum ASD and perimembranous and outflow tract or doubly committed subarterial VSD were imaged on the interatrial septal section and inflow and outflow interventricular septal section at parasternal or apical position, respectively.</p><p><b>RESULTS</b>The special echocardiographic section provided en face plane views of the congenital heart defects in 35/43 (81%) of secundum ASD and 10/15 (67%) of VSD patients, and allowed full assessment of their size, shape, circumference and spatial orientations to the neighboring structures, showing also the relationship between two or multiple defects.</p><p><b>CONCLUSION</b>The special transthoracic two-dimensional echocardiography not only displays the morphological features of ASD and VSD, but also provides additional information for making clinical decisions.</p>