As a rapid prototyping technology,three-dimensional (3D) printing is widely used in diagnosis and treatment of cardiovascular diseases.There are variable methods of 3D printing,and different forming methods have their respective advantages and disadvantages.3D printing plays an important role in congenital heart disease,valvular heart disease,aorta disease and arrhythmia.The application and the research progresses of 3D printing based on medical imaging in diagnosis and treatment of cardiovascular diseases were reviewed in this article.

Objective To analyze cardiac function of patients with first onset acute myocardial infarction (AMI)by speckle tracking imaging (STI).With clinical data of long-term follow-up,to explored the prognostic value of left ventricular functional reservation and damage after AMI.Methods Seventy-eight patients with first onset AMI were enrolled in the study.Dynamic images were acquired before primary percutaneous coronary intervention for the analyses of longitudinal peak systolic strain (LPSS), radial peak systolic strain (RPSS)and circumferential peak systolic strain (CPSS).Clinical data of long-term follow-up,results of electrocardiogram and coronary angiography were used for the evaluation of the recurrence risk of cardiac events and cardiac death after AMI.All the baseline clinical data and parameters of echocardiography were compared between patients with and without cardiac events and cardiac death during follow-up.Results Baseline clinical data of electrocardiogram and coronary angiography didn't show significant differences for the comparison of AMI patients with and without cardiac events and cardiac death during long-term follow-up.Compared to patients without cardiac events during follow-up,LPSS and CPSS (P <0.001)of patients with cardiac events were relatively lower and the prognostic value of CPSS (HR=1 .4096)for the recurrence risk of cardiac events was better.For the risk prediction of cardiac death,LPSS ( P <0.001,HR=1.5735)was relatively better.Conclusions Left ventricular functional reservation and damage after AMI were accurately assessed by STI,which helped predicted the recurrence risk of cardiac events and cardiac death of AMI patients.CPSS and LPSS were optimal indicators for the prediction of cardiac events and cardiac death,respectively.

Objective To evaluate left ventricular systolic synchronicity in patients with dilated cardiomyopathy by V-plane imaging and compare with clinical commonly used tissue Doppler imaging (TDI),evaluate the relevance and consistency between these two parameters.Methods 20 patients diagnosed with DCM and 20 healthy controls were enrolled,2D images,V-plane imaging and TDI waveform were acquired.Time to peak velocity of left ventricular 12 segments were measured by TDI and the standard deviation (TDI_SD) were calculated.Displacement time to peak were measured by V-plane and the standard deviation (V-plane_SD) were calculated.Results Compared with control group,TDI_SD and V-plane_SD increased significantly (P ＜ 0.01),TDI time to peak increased and V-plane time to peak decreased significantly(P ＜0.01).In the two group,12 segment time to peak measured by V-plane were significantly higher than TDI(P ＜ 0.01).There was a significant correlation between TDI_SD and V-plane_SD (r =0.925,P ＜0.001).Bland-Altman plot showed that 95％ plots of ratio of TDI_SD and V-plane_SD were among limits of agreement,which was (0.50,1.36).Conclusions Left ventricular systolic synchronicity in DCM patients can be observed by V-plane imaging.V-plane has significant relevance and consistency with TDI,and can overcome the limitations of TDI that 12 segments can not be displayed in the same cardiac cycle.

Objective To evaluate the value of selecting and locating coronary artery severe stenosis by the segmental longitudinal strain imaging diastolic indexes (LSI-DI).Methods 94 subjects with left ventricular ejection function (LVEF) ≥50％ and without regional wall motion abnormalities (RWMA) were divided into A group (coronary artery sever stenosis),B group (coronary artery light or mid stenosis) and C group (normal control) using coronary angiography.Some indexes were measured such as early diastolic mitral annulus velocity of septum (e),diastolic peak flow velocity of mitral valve (E,A) and E/e ratio.Using two-dimensional speckle tracking,indexes were measured such as segmental peak systolic longitudinal strain (PSLS),segmental longitudinal strain imaging diastolic indexes (LSI-DI) and global peak systolic longitudinal strain (GPSLS),global longitudinal strain imaging diastolic indexes (GLSI-DI).Compared these indexes among the three groups,the most valuabe segments were obtained and the optimal values were found out by ROC curve.Results There were no significant differences about GPSLS among the three groups.Coronary artery severe stenosis group were significantly lower than the other two groups on GLSI-DI (P ＜0.05);GLSI-DI of B group was lower than that of normal control group but the difference was not significant(P ＞0.05).The optimal cutoff values of LSI-DI were 45.5％ in the middle anteroseptal segment for detecting left anterior descending (LAD) artery severe stenosis (sensitivity 81.8％,specificity 84.2％),44.8％ in the basal anterolateral segment for detecting left circumflex (LCX) artery stenosis (sensitivity 87.3％,specificity 85.3％),and 48.3 ％ in the basal inferior segment for detecting right coronary (RCA) artery stenosis (sensitivity 79.6％,specificity 86.9 ％).Conclusions Patients with coronary artery severe stenosis can be screened by LSI-DI among patients with LVEF ≥50％ and without RWMA through conventional echocardiography.The middle anteroseptal segment,the basal anterolateral segment and the basal inferior segment can better locate the branches of coronary artery severe stenosis and the cutoff values were separately 45.5 ％,44.8 ％ and 48.3 ％.

Objective To measure left atrial appendage (LAA)in patients with atrial fibrillation using Flexi Slice imaging by real time 3D transesophageal echocardiography (TEE),and compare with common multiplane TEE.Methods Forty-six patients with atrial fibrillation were performed 2D and real time 3D TEE.Zero degree,45°,90° and 135° plane were acquired by 2D TEE and Flexi Slice remolding. Maximum and minimum values of ostium of left atrial appendage were acquired in the short axis view of LAA by Flexi Slice remolding.Results Compared with 2D TEE,values acquire by Flexi Slice in measurement of LAA ostium showed no significant difference(P >0.05).The depth measurement by Flexi Slicein 45° and 90° plane showed significant difference with 2D TEE (P-values were successively 0.045, 0.002),and in 0 and 135° plane showed no difference.All values measured by 2D TEE and Flexi Slices showed significant correlation.Bland-Altman plot showed that 94.29% of plots were among limits of agreement,which was (-2.5 mm,2.9 mm).The maximum values of LAA ostium values ranged from 30° to 160°,among which 87% (40/46 cases)distributed between 90° and 1 50°,and minimum values ranged from 0°to 160°,among which 85%(39/46 cases)distributed between 0°and 60°.Conclusions Measurement of LAA can be well achieved by Flexi Slice imaging,which showed significant advantage compared with 2D TEE.

Objective To explore the value of echocardiography in percutaneous left atrial appendage (LAA)closure for stroke prevention in patients with nonvalvular atrial fibrillation during procedure and for short-term follow-up.Methods Twenty patients were enrolled to undergo percutaneous LAA closure with the LAmbre device.Rheumatic valvular diseases were excluded by transthoracic echocardiography (TTE) and transesophageal echocardiography(TEE)before the closure procedure.TEE was performed during the procedure for the trans-septal puncture and the release of the closure device.Combined TEE with angiographic measurements,guidance for the optimal device size was provided.The closure effect and procedure-related complications were observed immediately by TEE and also evaluated by TTE at 1-day and 1-month follow-up.Results All patients underwent LAA occlusion successfully.TEE color Doppler evaluation have shown nine patients with complete closure immediately,one with a ≤ 1 mm residual LAA leak,and ten with a 1 -3 mm jet.There were no other complications during the procedure.One day after the closure,small pericardial effusions were observed for three patients while two of the three were free of the pericardial effusion at the 1-month follow-up.During the short-term follow-up,no damage was found at any anatomical structures near LAA due to the closure process,and there was no significant difference of cardiac function before and after the procedure.Conclusions With the guidance of TEE,the successful rate of percutaneous LAA closure procedure was preferable and the occurrence rate of compliance was acceptable. And TTE played an important role in patients'short-term follow-up.

Objective To evaluate the right ventricular function in patients with congestive heart failure (CHF) after cardiac resynchronization therapy (CRT) by 2-dimensional speckle imaging (2D-STI).Methods 46 patients with CHF were divided into responders to CRT and non-responders to CRT according the standard of a decline in LV end-systolic volume ≥ 10％.All the patients received echocardiography examination 1-3 days before CRT and 6 month after CRT.Tissue Doppler imaging (TDI) indices included SD of time to peak velocity in systole (Ts-SD) among 12 segments.Right ventricular diameters included RV basal transverse diameter (D1),RV middle transverse diameter (D2) and RV longitudinal diameter (D3) in apical four views.2D-STI indices included systolic strain (S) and stain rate (SR) of basal or middle segment of RV free wall.Results Compared with before CRT,LVEDd,LVEDV,LVESV and Ts-SD significantly decreased,LVEF significantly increased in responders 6 months after CRT.Before CRT,compared with nonresponders,there was no significant difference of D1,D2 and D3 in responders,while S and SR in basal or middle segment of RV free wall were higher than non-responders.Compared with before CRT,D1,D2 and D3 in responders decreased significantly,S and SR in basal or middle segment of RV free wall increased significantly,while there was no difference in non-responders.There were significant negative correlation between S and SR in basal or middle segment of RV free wall and Ts-SD in responders.Conclusions The remodeling and systolic function of RV are improved after CRT.It may help for improving the efficacy of CRT when takes RV function data into account before CRT.

Objective To explore value of two-dimensional speckle tracking imaging (2D-STI) strain parameters in assessment of left ventricular (LV) dyssynchrony and its relationship with cardiac function in patients with dilated cardiomyopathy (DCM).Methods Totally 25 patients with DCM and 25 age-matched normal controls were enrolled.The LV time to peak longitudinal strain (Tls) and time to peak circumferential strain (Tcs) were measured by 2D-STI,from which the standard deviations and maximal differences of the Tls in all 18 segments,6 segments at apical 4-chamber,3-chamber and 2 chamber views (Tls-SD,Tls-SD-4,Tls-SD-3,Tls SD-2,Tls dif,Tls-dif-4,Tls-dif-3,Tls-dif-2) were calculated,as same as the standard deviations and maximal differences of Tcs in all 18 segments,6 segments at mitral valve,papillary muscle,apical short-axis views (Tcs-SD,Tcs-SD-M,Tcs-SD-P,Tcs-SD-A,Tcs-dif,Tcs-dif-M,Tcs-dif-P,Tcs-dif-A) were calculated.Results Compared with the control group,the global and segmental strain parameters of the DCM group increased significantly (all P＜0.05).Except for Tcs-dif-P and Tcs dif,the residual strain parameters were negatively correlated with LV ejection fraction (all P＜0.05).Except for Tcs-dif-M,Tcs dif-P and Tcs-dif,there was a positive correlation between strain parameters and E/e in DCM group (all P ＜0.05).Conclusion In patients with DCM,LV dyssynchrony exists both in global and regional,which may aggravates the LV function damage.2D-STI strain parameters can objectively evaluate LV dyssynchrony and its relationship with cardiac function in patients with DCM.

Objective To explore the clinical value of two‐dimensional transesophageal echocardiography (2D‐TEE) and real‐time three‐dimensional transesophageal echocardiography (RT3D‐TEE) for the left atrial appendage (LAA) closure procedures by the visualization of LAA shape by 2D‐TEE and RT3D‐TEE and the comparison between the measurement of LAA ostium and the sized LAmbreTM device during the procedure .Methods Forty‐one atrial fibrillation patients ,who had undergone 2D‐TEE examination at our hospital ,were enrolled in the study .At the mid‐esophageal ,dimensions of inner and outer ostium and depth of LAA were measured at the 2D‐TEE views of 0 ,45 ,90 and 135 degree respectively . RT3D‐TEE views were acquired and the maximal and the minimal dimensions of LAA inner ostium were measured .The measurement by RT3D‐TEE and 2D‐TEE were compared to find the difference and correlation .Eleven of 41 patients who have complied with the requirements for the LAA closure ,were undergone the procedures ,measured the dimension of LAA inner ostium at selective angiography intraoperative .Sizes of closure disks of the closure device and the measurement at selective angiography were recorded to compare the measurement at RT3D‐TEE and 2D‐TEE .Results Forty‐one atrial fibrillation patients were completed TEE examination successfully .Inner ostial dimension of LAA was (20.0±04.3)cm,(19.7±03.8)cm,(21.2±04.6)cm,(23.0±05.0)cmat2D‐TEEviewsof0,45,90and135 degree ,respectively .The maximum dimensions of LAA inner ostium by RT3D‐TEE was (2 4.9 ± 0 5.2)cm . At 2D‐TEE views ,the maximum dimensions of LAA inner ostium was at 135 degree ,there was a difference between it and the measurement by RT3D‐TEE ( P =0 0.12) .Monitoring by TEE ,LAA closure procedures with LAmbreTM device were successful for all 11 patients ,the landing zone by selective angiography was (2 4.9 ± 0 4.4)cm ,and the appropriate sized closure disk of the LAmbreTM device was 2 4. - 3 6. cm . Correlation between the measurements by RT3D‐TEE and selective angiography and the sized closure disk were r =0 8.16 ,P =0 0.02 and r =0 9.14 ,P =0 0.00 ,respectively .Correlation between the measurements by 2D‐TEE and selective angiography and the sized closure disk were r =0 6.93 ,P =0 0.18 and r =0 6.88 , P=0 0.19 ,respectively .Conclusions There was better correlation among the measurements by RT3D‐TEE and selective angiography and the size of closure device .Therefore ,compared to 2D‐TEE ,the guidance of RT3D‐TEE was more accurate during LAA closure procedures for LAmbreTM device selection .

Objective To assess the impact of a single hemodialysis on the left ventricular systolic function of uremia patients with 3-dimensional ultrasound speckle tracking imaging (3D-STI).Methods Thirty-seven clinically stable outpatients with uremia undergoing hemodialysis were studied.The echocardiographic examinations were obtained in 30 minutes before and after homodialysis.Twenty nine normal subjects with age and sex matched were selected as control groups.Conventional ultrasound was recorded and then left ventricular mass index(LVMI) was calculated.The peak systolic mitral annular velocity S' was recorded by tissue Doppler imaging.3D-STI imaging were recorded from standard left ventricular apical 4-chamber views before and after a single hemodialysis.Left ventricular end diastolic volume (LVEDV),left ventricular end systolic volume (LVESV),left ventricular ejection fraction (LVEF),and left ventricular global longitudinal peak systolic strain (LVGLS),left ventricular global radial peak systolic strain (LVGRS),left ventricular global circumferential peak systolic strain (LVGCS),left ventricular global area peak systolic strain (LVGAS) were measured.The indicators of conventional ultrasound and 3D-STI were compared between the pre-hemodialysis group and the normal control group,and also between pre-and post-hemodialysis groups.Results ①Compared with the control group,the left ventricular end-diastolic diameter (LVDD),interventrieular septal thickness at diastole (IVSD),left ventricular posterior wall thickness at diastole(LVWPD),left atrial diameter(LAD) in the group before a single hemodialysis were significantly higher (P ＜0.05 for all).Meanwhile,the S' was significantly lower (P ＞0.05) and LVMI was significantly higher in the pre-hemodialysis group than the control group(P ＜ 0.05).The LVDD,LAD,left atrial volume index(LAVI) were significantly lower in the post-hemodialysis group than that in the pre-hemodialysis group(P ＜0.05 for all).②Results of 3D-STI showed that the LVEF,LVGLS,LVGCS,LVGRS,LVGAS was significantly lower,however LVEDV,LVESV were higher in the pre-hemodialysis group compared with the control group (P ＜ 0.05 for all).After a single hemodialysis,LVEDV,LVESV,LVGLS were significantly lower than before(P ＜0.05 for all),but LVEF,LVGRS,LVGCS,LVGAS were not significantly changed (P ＞ 0.05 for all).Conclusions After a single hemodialysis,the whole systolic function of the left ventricular was not changed.but the left ventricular global longitudinal peak systolic strain was significantly lower.The parameter of LVGLS was sensitive to the change of preload and was volume-load dependent.The preload of the patients should be sufficiently considered when the LVGLS are measured in the patients with uremia undergoing hemodialysis.