[Show abstract][Hide abstract]ABSTRACT: We aimed to investigate whether left ventricular (LV) twist analysis can detect the extent of myocardial fibrosis in patients with hypertrophic cardiomyopathy (HCM). This prospective case–control study recruited 81 consecutive patients with HCM examined between January 2012 and April 2013. Data of 76 patients were analyzed after excluding 5 patients whose echocardiographic images were of poor quality. Healthy volunteers (n = 46) served as controls. Both groups underwent comprehensive echocardiographic examination (i.e., Bas-Rotation, AP-Rotation, LVEF, LADs, IVST, LAVi, E/Em, LVMI, advanced LV-twist analysis by speckle tracking echocardiography) and magnetic resonance imaging. Between-group differences were analyzed by independent t test; logistic regression analysis was performed to identify effect factors. No significant differences were found between baseline characteristics of HCM and control groups (all p > 0.05). HCM patients had significantly higher Bas-Rotation, AP-Rotation, LV Twist, LVEF, LADs, IVST, LAVi, E/Em and LVMI than controls (all p < 0.0001) and significantly lower LVDd and E/A (both p < 0.001). Bas-Rotation, AP-Rotation, LV-Twist, LADs, IVST, LAVi, E/Em and LVMI were significantly higher in HCM patients with fibrosis than in those without fibrosis (p < 0.001), but no significant differences in other echocardiographic parameters were found between those with and without fibrosis. Age, Bas-Rotation, AP-Rotation, LV twist, LADs, IVST, LAVi, E/A, E/Em, and LVMI were significant effect factors for fibrosis. AUROC analysis showed that LV twist had high discriminatory power to detect extent of myocardial fibrosis (AUC 0.996, 95 % CI 0.989–1.004, p < 0.001). Left ventricular twist mechanics are associated with the extent of myocardial fibrosis. LV-twist assessment by STE may be clinically useful.
Preview · Article · Aug 2014 · The International Journal of Cardiovascular Imaging
[Show abstract][Hide abstract]ABSTRACT: The prevalence of myocardial perfusion and glucose metabolic abnormalities and their significance in patients with isolated left ventricular non-compaction (ILVNC) have not been well investigated.
Seventeen ILVNC patients who underwent cardiac magnetic resonance (CMR) and (99m)Tc-sestamibi SPECT/fluorine-18 deoxyglucose ((18)F-FDG) PET imaging were included. Left ventricular non-compaction, regional wall motion abnormalities, left ventricular ejection fraction (LVEF), and delayed enhancement (DE) were estimated using CMR. Myocardial perfusion and metabolism were evaluated with SPECT/PET.
Ninety-five (32.9%) segments were considered non-compacted. DE was present in 52 (18.0%) segments and 10 (58.8%) patients. The rate of occurrence of DE was significantly higher in compacted segments than in non-compacted segments (22.7% vs 8.4%, P = .003). Myocardial perfusion abnormalities were present in 92 (31.8%) segments, of which 66 were perfusion/metabolism match and 26 were perfusion/metabolism mismatch. The rate of occurrence of perfusion abnormality was similar between compacted and non-compacted segments (32.0% vs 31.6%, P = .948), but it was significantly higher in segments with DE than in those without DE (51.9% vs 27.4%, P = .001). None of the imaging features alone (non-compaction, DE, perfusion abnormalities, match or mismatch) showed significant correlations with LVEF (all P > .05).
In the current study, myocardial perfusion/metabolism mismatch and match were observed in both non-compacted and compacted myocardium in ILVNC patients. Further research is warranted to determine their pathologic and clinical significance.
[Show abstract][Hide abstract]ABSTRACT: Previous studies have shown that viable myocardium predicts recovery of left ventricular (LV) dysfunction after revascularization. Our aim was to evaluate the prognostic value of myocardial scar assessed by late gadolinium-enhanced cardiovascular magnetic resonance imaging (LGE-CMR) on functional recovery in patients undergoing coronary artery bypass grafting (CABG).
From November 2009 to September 2012, 63 patients with reduced left ventricular ejection fraction (LVEF) referred for first-time isolated CABG were prospectively enrolled, 52 were included in final analysis. LV functional parameters and scar tissue were assessed by LGE-CMR at baseline and 6 months after surgery. Patency of grafts was evaluated by computed tomography angiography (CTA) 6 months post-CABG. Predictors for global functional recovery were analyzed.
The baseline LVEF was 32.7±9.2%, which improved to 41.6±11.0% 6 months later and 32/52 patients improved LVEF by ≥5%. Multivariate logistic regression analysis showed that the most significant negative predictor for global functional recovery was the number of scar segments (Odds ratio 2.864, 95% Confidence Interval 1.172-6.996, p = 0.021). Receiver-Operator-Characteristic (ROC) analysis demonstrated that ≤4 scar segments predicted global functional recovery with a sensitivity and specificity of 85.0% and 87.5%, respectively (AUC = 0.91, p<0.001). Comparison of ROC curves also indicated that scar tissue was superior to viable myocardium in predicting cardiac functional recovery (p<0.001).
Our findings indicated that scar tissue on LGE-CMR is an independent negative predictor of cardiac functional recovery in patients with impaired LV function undergoing CABG. These observations may be helpful for clinicians and cardiovascular surgeons to determine which patients are most likely to benefit from surgical revascularization.
[Show abstract][Hide abstract]ABSTRACT: In a swine model of acute myocardial infarction (AMI), Statins can enhance the therapeutic efficacy of mesenchymal stem cell (MSCs) transplantation. However, the mechanisms remain unclear. This study aims at assessing whether atorvastatin (Ator) facilitates the effects of MSCs through activation of nitric oxide synthase (NOS), especially endothelial nitric oxide synthase (eNOS), which is known to protect against ischemic injury.
42 miniswines were randomized into six groups (n = 7/group): Sham operation; AMI control; Ator only; MSC only, Ator+MSCs and Ator+MSCs+NG-nitrol-L-arginine (L-NNA), an inhibitor of NOS. In an open-heart surgery, swine coronary artery ligation and reperfusion model were established, and autologous bone-marrow MSCs were injected intramyocardium. Four weeks after transplantation, compared with the control group, Ator+MSCs animals exhibited decreased defect areas of both "perfusion" defined by Single-Photon Emission Computed Tomography (-6.2±1.8% vs. 2.0±5.1%, P = 0.0001) and "metabolism" defined by Positron Emission Tomography (-3.00±1.41% vs. 4.20±4.09%, P = 0.0004); Ejection fraction by Magnetic Resonance Imaging increased substantially (14.22±12.8% vs. 1.64±2.64%, P = 0.019). In addition, indices of inflammation, fibrosis, and apoptosis were reduced and survivals of MSCs or MSC-derived cells were increased in Ator+MSCs animals. In Ator or MSCs alone group, perfusion, metabolism, inflammation, fibrosis or apoptosis were reduced but there were no benefits in terms of heart function and cell survival. Furthermore, the above benefits of Ator+MSCs treatment could be partially blocked by L-NNA.
Atorvastatin facilitates survival of implanted MSCs, improves function and morphology of infarcted hearts, mediated by activation of eNOS and alleviated by NOS inhibitor. The data reveal the cellular and molecular mechanism for anti-AMI therapy with a combination of statin and stem cells.
[Show abstract][Hide abstract]ABSTRACT: Supporting Tables S1–S8 and Figures S1–S3. Table S1. Serum lipids at baseline and endpoint. Table S2. 99mTc-MIBI SPECT evaluation of the myocardial perfusion defect proportion. Table S3. 18F-FDG PET-CT evaluation of myocardial metabolism defect size and proportion. Table S4. MRI evaluation of the parameters of left ventricular function. Table S5. Inflammation score and CVF. Table S6. TUNEL apoptosis index and Hs-CRP. Table S7. RT-PCR of NOS subtype mRNA expression. Table S8. Western Blotting. Figure S1. The purity of MSCs. Figure S2. The growth curves of MSCs. Figure S3. Differentiation of MSCs.
[Show abstract][Hide abstract]ABSTRACT: To analyze the incidence of coronary artery disease (CAD) and outcome of patients with left ventricular noncompaction (LVNC).
Fifty-one patients with LVNC evaluated by echocardiography and/or cardiac magnetic resonance (CMR) from January 2006 to August 2010 were retrospectively reviewed. Coronary angiography or MDCT was performed for detecting coronary artery disease. Predictors of the cardiac events were analyzed by Cox regression analysis.
There were 31 LVNC patients without CAD and 20 LVNC patients with CAD including single vessel coronary disease in 9 cases, double vessel coronary disease in 3 cases, three vessel coronary disease in 5 cases and left main coronary disease in 3 cases. Coronary artery bypass graft and percutaneous coronary intervention (PCI) were performed in 4 patients. Compared to LVNC patients without CAD, mean age (P = 0.008), incidence of hypertension (65.0% vs. 19.4%, P = 0.001), diabetes mellitus (40.0% vs. 12.9%, P = 0.026) and hyperlipidemia (55.0% vs. 25.8%, P = 0.035) were significantly higher while NT-proBNP level was significantly lower (P = 0.049) in LVNC patients with CAD. Incidence of major cardiac events was similar in LVNC patients with or without CAD. LogNT-proBNP is the independent prognostic factor for adverse cardiac events in patients with LVNC (HR 3.993, 95%CI 1.140 - 13.988, P = 0.030).
Coronary artery disease is common in patients with LVNC and associated with traditional risk factors for CAD. Poor prognosis is associated with increased NT-proBNP but not with CAD in this patient cohort.
No preview · Article · Aug 2011 · Zhonghua xin xue guan bing za zhi [Chinese journal of cardiovascular diseases]
[Show abstract][Hide abstract]ABSTRACT: To evaluate the clinical characteristics of left ventricular fat replacement.
We identified 45 patients [28M/17F, mean age (51.9 ± 14.7) years] with left ventricular myocardial fat replacement (CT value ≤ -30 Hu) by cardiovascular CT.
Among 45 patients, 25 patients [20M/5F, mean age (61.2 ± 10.4) years]were diagnosed as coronary artery disease (CAD). There was 56%single-vessel disease, 20% double-vessel disease and 24%triple-vessel disease, true left ventricular aneurysm was detected in 3 patients and left ventricular thrombi in 1 patient, the dimension of left ventricle was (54.5 ± 9.4) mm and the LVEF was (51.8 ± 13)% in CAD group. In this group, fat replacement occurred in the region of myocardial infarction and presented as curvilinear band in subendocardial region. The left ventricular wall thickness was lower than 5 mm in 21 cases. The location of fat replacement in CAD group is as follows: apical region in 18 patients, distal septal in 15 patients, distal anterior in 11 patients, mid-septal in 7 patients, mid-anterior in 7 patients and basal in 1 patients. The age of remaining 20 patients (8M/12F) without CAD were (57.8 ± 13.3) years. In the group of non-CAD, dilated cardiomyopathy was diagnosed in 3 patients, atrial septal defect in 1 patient, rheumatic heart disease in 1 patient, there was no structural heart disease in the remaining 15 patients. The dimension of left ventricle was (51.1 ± 9.1) mm and the LVEF was (59.4 ± 13.9)%. In non-CAD group, fat replacement mainly occurred in septal region, presented as curvilinear band in 17 patients and patch in 3 patients. The location of fat replacement in this group is as follows: mid-septal region in 11 patients, distal-septal in 10 patients and apical in 9 patients. The intramural fat replacement was detected in 14 patients: subendocardial fat replacement in 10 patients and both intramural and subendocardial fat replacement in 4 patients.
Left ventricular fat replacement could be documented in CAD patients, non-CAD cardiomyopathy patients and in patients without structural heart disease. Left ventricular fat replacement often positioned in apical region in CAD patients as a consequence of infarct healing while mostly positioned in septal region in non-CAD patients, the definite clinical implication of left ventricular fat replacement in non-CAD patients remains to be clarified.
No preview · Article · Feb 2011 · Zhonghua xin xue guan bing za zhi [Chinese journal of cardiovascular diseases]
[Show abstract][Hide abstract]ABSTRACT: To observe the value of cardiac magnetic resonance imaging (MRI) for differentiation of true from false left ventricular aneurysm in patients after myocardial infraction (MI).
Twenty-six patients [22 males/4 females, mean age (59.3 ± 9.3) years] with left ventricular aneurysm after MI were imaged with MRI, echocardiography and coronary angiography. The respective findings were compared with surgical pathology results.
There were 24 patients with dyspnea and 15 patients with hypertension. LVEF measured by echocardiography was 36.9% ± 9.1% in this patient cohort. Cardiac MRI showed that the left ventricular end diastolic wall thickness was thinner than 5.5 mm in 24 cases, and between 5.5 to 8 mm in 2 cases. The dimension of left ventricle was (67.8 ± 9.3) mm. Dyskinesia presented in 24 cases, and akinesia in 2 cases. Delayed enhancement was shown in all cases by MRI. Cardiac MRI detected left ventricular true aneurysm in 23 cases, false aneurysm in 3 case and left ventricular thrombi in 7 cases. The diagnosis by magnetic resonance imaging corresponded well to pathological findings. Echocardiography misdiagnosed pseudoaneurysm in 1 patient, and failed to detected left ventricular thrombi in 2 cases.
Cardiac MRI could correctly differentiate true from false left ventricular aneurysm in patients after MI.
No preview · Article · Jan 2011 · Zhonghua xin xue guan bing za zhi [Chinese journal of cardiovascular diseases]
[Show abstract][Hide abstract]ABSTRACT: To analyze the stem cell re-distribution after intra-coronary infusion (ICI) into arrested and beating hearts in a swine myocardial infarction (MI) model using magnetic resonance imaging (MRI).
Bone marrow-derived mesenchymal stem cells were obtained from male swine and labeled with iron oxide during culture. One week after MI in female swine, the survivors were randomly divided into 4 groups. Cardiopulmonary bypass was set up to arrest the heart, and then SPIO labeled male stem cells (1 × 10(8)) were infused through coronary of beating heart (n = 6) and the arrested heart (n = 6). Saline was injected in either the beating or arresting heart as respective controls. Three days later, cell distribution was assessed by T2(*) change with magnetic resonance imaging and Y-chromosome (SRY) was detected with quantitative polymerase chain reaction.
The reduction of T2(*) values was significantly different in the hearts, spleens, livers and lung between the transplantation groups and the control groups. Only few transplanted cells were localized in the heart and T2(*) values were similar between beating and arrest heart groups [(-7.81 ± 2.03) ms vs. (-6.56 ± 1.72) ms, P > 0.05], while T2(*) value reduction was more significant in the spleen and liver in arrest heart group than in beating heart group [spleen: (-16.72 ± 2.83) ms vs. (-22.18 ± 3.98) ms, P < 0.01, liver: (-2.40 ± 0.44) ms vs. (-5.32 ± 3.40) ms, P < 0.05]. T2(*) value was similar in kidney among the four groups. qRT-PCR detected SRY gene was similar in the heart, less in the spleen and liver while more in the lung in beating heart group compared to arrested heart group. In vitro Prussian blue stained positively transplanted cells were found in the above organs in transplantation group.
The majority of stem cells transplanted by ICI would be entrapped by the extracardiac organs. Stem cell transplantation via ICI into the arrested heart does not favor more cells retention in the injured myocardium. Further investigation is needed to optimize the approach of stem cell delivery.
No preview · Article · Nov 2010 · Zhonghua xin xue guan bing za zhi [Chinese journal of cardiovascular diseases]
[Show abstract][Hide abstract]ABSTRACT: To characterize the clinical and cardiac MRI features of dilated cardiomyopathy (DCM) and left ventricular noncompaction (LVNC).
Compared the clinical and MRI features between 25 patients with LVNC and 21 patients with DCM. The MRI derived diastolic left ventricular wall thickness and the number and degree of noncompaction (NC) were evaluated using the 17-segment model.
Chest distress, shortness of breath and abnormal ECG were presented in all DCM patients, abnormal ECG was evidenced in 22 LVNC patients and 21 out of 25 LVNC patients presented similar clinical symptoms as DCM patients while the rest 4 LVNC patients were asymptomatic. Left atrial and ventricular dimensions were significantly smaller in LVNC patients compared to DCM patients. The degree of left ventricular (LV) spherical remodeling was significantly greater in patients with DCM (sphericity index, SI = 0.81 +/- 0.06) than in patients with LVNC (SI = 0.74 +/- 0.11, P < 0.05). The LV ejection fraction (LVEF) was significantly higher in patients with LVNC (32.7% +/- 14.2%) than that in patients with DCM (15.0% +/- 5.1%). The number of NC segments in LVNC patients (9 +/- 1) was significantly higher than the number of hypertrabeculation segment in DCM patients (5 +/- 2). The left ventricular apex (the 17th segment) was unexceptionally involved in all LVNC patients, while hypertrabeculation was absent in the 17th segment of DCM patients. The NC was more common in the apical and mid segments (16th, 12th and 11th segments) than in basal and mid septal segments (2nd, 3rd, 8th and 9th segments) in both LVNC and DCM patients. The thickness of compacted myocardium of the segments associated with noncompaction appeared thin in two groups. The wall thickness of noncompaction myocardium segments was thicker in LVNC patients than in DCM patients. The end-diastolic NC/C ratio was, on average, higher in patients with LVNC (3.3 +/- 0.6) than in patients with DCM (1.9 +/- 0.3).
The clinical manifestation is similar while there are significant differences in the morphology and function of left atria and left ventricle between the LVNC and DCM patients. The different distribution and degree of NC were helpful to differentiate LVNC from DCM.
No preview · Article · May 2010 · Zhonghua xin xue guan bing za zhi [Chinese journal of cardiovascular diseases]
[Show abstract][Hide abstract]ABSTRACT: The goal of this study was to evaluate the accuracy of gated single photon emission computed tomography (SPECT) in the assessment of left ventricular (LV) end-diastolic/end-systolic volumes (EDV, ESV) and ejection fraction (LVEF) in patients with dilated cardiomyopathy, using cardiac magnetic resonance imaging (MRI) as the reference method. Furthermore, software-specific characteristics of Quantitative Gated SPECT (QGS), Emory Cardiac Toolbox (ECTB) and 4D-MSPECT were analysed.
Thirty-six patients with dilated cardiomyopathy who underwent gated (99m)Tc-methoxyisobutylisonitrile SPECT and cardiac MRI were included. LV EDV, ESV and LVEF values of gated SPECT were calculated using QGS, ECTB and 4D-MSPECT.
The correlation between the results of gated SPECT and cardiac MRI was excellent for EDV [R = 0.872 (QGS), R = 0.879 (ECTB), R = 0.869 (4D-MSPECT)], ESV [R = 0.908 (QGS), R = 0.897 (ECTB), R = 0.880 (4D-MSPECT)] and LVEF [R = 0.794 (QGS), R = 0.763 (ECTB), R = 0.710 (4D-MSPECT)]. EDV and ESV assessed by QGS did not differ significantly from those assessed by cardiac MRI (all p = NS), whereas EDV and ESV were overestimated by ECTB and 4D-MSPECT compared with cardiac MRI (all p < 0.05). LVEF was overestimated by QGS, ECTB and 4D-MSPECT compared with cardiac MRI (all p < 0.05).
The correlation between gated SPECT and cardiac MRI is excellent for LV volume and LVEF values calculated by QGS, ECTB and 4D-MSPECT in patients with dilated cardiomyopathy. However, algorithm-varying over- or underestimation of LV volumes and LVEF should be accounted for in the clinical context.
No preview · Article · Apr 2009 · European Journal of Nuclear Medicine
[Show abstract][Hide abstract]ABSTRACT: To investigate the efficacy of transplantation of mesenchymal stem cells (MSC) with gelatin microspheres containing vascular endothelial growth factor in ischemic regions in infracted swine hearts.
Twelve Chinese mini swines with infarction were randomized to receive autogenetic MSC injection to the peri-infarction area of left ventricular wall (MSC group, n = 6) or MSC transplantation with gelatin hydrogel microspheres incorporating vascular endothelial growth factor (VEGF-MSC group, n = 6). Three weeks later, left ventricular function was assessed by magnetic resonance imaging (MRI). The contrast of the MSC hypointense lesion was determined using the difference in signal intensity between the hypointense and normal myocardium divided by signal intensity of the normal region. Myocardial capillary density, the number of DAPI positive MSC and the apoptotic MSC were also determined.
The diameter of the microspheres averaged (104.0 +/- 22.6) microm. At 24 hours after transplantation, MSC were identified by MRI as large intramyocardial signal voids at injection sites which persisted up to 3 weeks. There was no significant difference in the contrast of the lesions and in the size of the lesions at 24 hours between two groups. At 3 weeks after injection, the size of the lesions and the contrast of the lesion were decreased (P < 0.05) in both groups. The capillary density of the injection site was significantly more in the MSC-VEGF microsphere group than that in MSC group [(15.2 +/- 5.4)/HPF vs. (10.2 +/- 5.0)/HPF, t = 2.43, P < 0.05], and there were more dense DAPI labeled MSC per high power fields in injection sites of MSC-VEGF microsphere group than that in MSC group [(354 +/- 83)/HPF vs. (278 +/- 97)/HPF, t = 3.14, P < 0.05]. Moreover, the apoptosis rate of MSCs of MSCs-VEGF microsphere group was less than that of MSC group [(6.4 +/- 4.1)% vs. (11.9 +/- 4.8)%, t = 2.97, P < 0.05].
MSC transplantation with gelatin hydrogel microspheres incorporating VEGF enhanced the efficacy of MSC in this swine model of myocardial infarction. MRI tracking of MSC is feasible and represents a preferred method for studying the engraftment of MSCs in infracted tissue.
No preview · Article · Mar 2009 · Zhonghua xin xue guan bing za zhi [Chinese journal of cardiovascular diseases]
[Show abstract][Hide abstract]ABSTRACT: To evaluate the therapeutic effects of stem cell transplantation in heart failure patients with old myocardial infarction (OMI) by MRI.
Heart failure patients [NYHA 2.7 +/- 0.7, male = 18, mean age (59.5 +/- 10.1) y] with OMI were randomly divided into 2 groups (group A: CABG + stem cell transplantation, group B: CABG; n = 10 each). Left ventricular (LV) function was measured by MRI, viable myocardium was detected by (18)F-FDG myocardial metabolism imaging and late contrast-enhanced at baseline and 6 months post intervention.
LVEF and LVEDV at baseline for group A were (20.71 +/- 6.09)% and (172.73 +/- 32.74) ml, and for group B were (27.59 +/- 2.31)% and (155.13 +/- 28.36) ml, respectively (P > 0.05). The LVEF was equally improved in group A and B (mean 8.63% vs. 10.37%, P > 0.05) while DeltaLVEDV was significant higher in group A than that in group B [(9.91 +/- 39.50) ml vs. (-22.34 +/- 31.35) ml, P < 0.05]. Ventricular wall thickening ratio at 6 months post intervention was significantly higher in group A than that in group B [(11.40 +/- 11.53)% vs. (2.27 +/- 7.20)%, P < 0.05]. Late contrast-enhanced MRI results correlated with (18)F-FDG myocardial metabolism imaging SPECT well in assessment of myocardial viability (kappa value: 0.446, P < 0.001; sensitivity: 68.3% and specificity: 92.5%).
Stem cell therapy on top of CABG aggravated LV remodeling in heart failure patients with old myocardial infarction. The specificity of MRI is similar to (18)F-FDG SPECT while the sensitivity is inferior to (18)F-FDG SPECT on detecting viable myocardium.
No preview · Article · Nov 2008 · Zhonghua xin xue guan bing za zhi [Chinese journal of cardiovascular diseases]
[Show abstract][Hide abstract]ABSTRACT: To investigate whether Atorvastatin (Ator) treatment improves the cardiac micro-environment that facilitates survival and differentiation of bone-marrow-derived mesenchymal stem cells (MSCs) implanted in the post-infarct myocardium.
Myocardial infarction was created by coronary ligation and immediately after reperfusion, autologous bone-marrow-derived MSCs were transplanted into the hearts of Chinese swine that were pretreated with or without Ator. Six weeks after transplantation, as evaluated by SPECT and MRI all the animals with Ator showed improved cardiac perfusion and contractility when compared with untreated. Increased survival and differentiation of implanted MSCs and decreased infarct area were observed in the Ator-treated, MSC-implanted animals. In the absence of Ator, MSC transplantation only achieved a modest improvement in perfusion and morphology. The combined treatment with Ator and MSCs significantly inhibited cardiac cell apoptosis, reduced oxidative stress, and suppressed expression of the inflammatory cytokines in the post-infarct myocardium.
Ator treatment may protect the myocardium undergoing acute infarction and reperfusion by creating a better environment for the survival and differentiation of implanted MSCs. The benefit of the Ator/stem cell combined therapy may result from the statin-mediated inhibition of apoptosis, oxidative stress, and inflammation in the infarcted myocardium.
Full-text · Article · Jul 2008 · European Heart Journal
[Show abstract][Hide abstract]ABSTRACT: Treatment of ischemic heart disease remains an important challenge, though there have been enormous progresses in cardiovascular therapeutics. This study was conducted to evaluate whether Tongxinluo (TXL) treatment around the transplantation of mesenchymal stem cells (MSCs) can improve survival and subsequent activities of implanted cells in swine hearts with acute myocardial infarction (AMI) and reperfusion.
Twenty-eight Chinese mini-pigs were divided into four groups including a control group (n = 7); group 2, administration of low-dose TXL alone from the 3rd day prior to AMI to the 4th day post transplantation (n = 7); group 3, MSCs alone (n = 7) and group 4, TXL + MSCs (n = 7). AMI models were made by occlusion of the left anterior descending coronary artery for 90 minutes. Autologous bone marrow-MSCs (3 x 10(7) cells/animal) were then injected into the post-infarct myocardium immediately after AMI and reperfusion. The survival and differentiation of implanted cells in vivo were detected by immunofluorescent analysis. The data of cardiac function were obtained at baseline (1 week after transplantation) and endpoint (6 weeks after transplantation) by single photon emission computed tomography (SPECT) and magnetic resonance imaging (MRI). Apoptosis was detected by TUNEL assay and the oxidative stress level was investigated in the post-infarct myocardium at endpoint.
At endpoint, there was less fibrosis and inflammatory cell infiltration with more surviving myocardium in group 4 than in the control group. In group 4 the survival and differentiation of implanted MSCs were significantly improved more than that seen in group 3 alone (P < 0.0001); the capillary density was also significantly greater than in the control group, group 2 or 3 both in the infarcted zone (P < 0.0001) and the peri-infarct zone (P < 0.0001). MRI showed that parameters at baseline were not significantly different between the 4 groups. At endpoint, regional wall thickening and the left ventricular ejection fraction were increased while the left ventricular mass index, dyskinetic segments and infarcted size were decreased only in group 4 compared with control group (P < 0.0001). SPECT showed that the area of perfusion defect was significantly decreased at endpoint only in group 4 compared with control group (P < 0.0001). TUNEL assay indicated that TXL administration significantly decreased cell apoptosis in peri-infarct myocardium in groups 2 and 4. Furthermore, superoxide dismutase (SOD) significantly increased and malondialdehyde (MDA) decreased in groups 2 and 4 by the administration of TXL.
Our study demonstrates the following: (1) immediate intramyocardial injection of MSCs after AMI and reperfusion resulted in limited survival and differentiation potential of implanted cells in vivo, thus being incapable of beneficially affecting post-hearts; (2) TXL-facilitation resulted in a significant survival and differentiation potential of implanted cells in vivo via inhibition of apoptosis and oxidative stress, accompanied by significant benefits in cardiac function.
No preview · Article · Aug 2007 · Chinese medical journal
[Show abstract][Hide abstract]ABSTRACT: To evaluate the diagnostic value of magnetic resonance imaging (MRI) for arrhythmogenic right ventricular cardiomyopathy (ARVC).
MRI was performed in 27 (male 21, mean age: 37.4 y, ranging from 15 - 67 y) clinically diagnosed ARVC patients according to the 1994 ARVC diagnosis criteria of WHO from Oct. 2004 to Jun. 2006. Heart chamber size, fat infiltration, local or global ventricular function, myocardium perfusion of contrast first pass and late enhancement were examined.
Fat infiltration was found in 24 (88.89%), trabecular disarray in 17 (62.96%), significant dilated right ventricle outlet (RVOT) in 18 (66.67%), dilated RV apex in 14 (51.85%), dilated RV free wall and posterior wall in 18 (66.67%) and right atrium enlargement in 11 (40.74%) patients. Local RV dysfunction was found in 18.52% (5/27), global RV dysfunction in 70.37% (19/27) of patients with mean RV ejection fraction (EF) of 35%. Left ventricle was affected in 40.74% (11/27) of patients. Perfusion defects were found in only 10.52% (2/19) of patients. Positive late enhancement of myocardium were found in 36.84% (7/19) of patients and affecting mainly the wall of RVOT and the free wall associated with lateral wall enhancement of LV. Five patients received heart transplantation and histology on transplanted hearts confirmed the MRI findings.
"One-stop-shop" MRI scanning can be used for the diagnosis of ARVC. While for some ARVC cases with dominant abnormality in LV, it is difficult for MRI to differentiate ARVC from dilated cardiomyopathy or coronary heart disease. We found fibrosis of lateral wall of LV can be a characteristic sign of ARVC.
No preview · Article · Jan 2007 · Zhonghua xin xue guan bing za zhi [Chinese journal of cardiovascular diseases]
[Show abstract][Hide abstract]ABSTRACT: The aim of this study was to investigate the feasibility and accuracy of delayed enhancement magnetic resonance imaging (DE-MRI) for the assessment of myocardial viability in patients with myocardial infarction in comparison with (99)Tc(m)-sestamibi (MIBI) single photon emission computed tomography (SPECT) and (18)F-fluorodeoxyglucose (FDG) SPECT. Scar was defined as regionally increased MRI signal intensity 15 minutes after injection of 0.2 mmol/kg gadolinium-diethylenetriamine pentaacetic acid or reduced perfusion and glucose metabolism defined by SPECT.
A total of 34 patients with myocardial infarction (29 males, 58.0 +/- 9.8 years) were imaged with MRI and SPECT.
A total of 578 segments were analyzed. DE-MRI and SPECT identified 431 and 336 viable segments respectively and SPECT also identified 30 ischemic segments. Necrotic segments identified by DE-MRI and SPECT were 147 and 212 respectively. Sensitivity and specificity of DE-MRI in identifying segments with matched flow/metabolism defects (scar tissues) was 61.3% and 95.4%, respectively. Quantitatively assessed relative MRI infarct area correlated well with SPECT infarct size. The value of Kappa was 0.51.
DE-MRI provides a good tool for differentiating viable myocardium from scar tissues and the detection accuracy is comparable between DE-MRI and SPECT.
No preview · Article · Jan 2007 · Zhonghua xin xue guan bing za zhi [Chinese journal of cardiovascular diseases]
[Show abstract][Hide abstract]ABSTRACT: To observe the clinical and magnetic resonance imaging (MRI) characterizations in patients with isolated left ventricular noncompaction (LVNC).
All patients were examined by MRI. The LV was divided into 9 segments for localizing non compacted segments. A new value, C/VS, was introduced to assess the degree of non compacted segments.
A total of 31 patients was diagnosed as LVNC (23 males; 39.9 +/- 15.7 years). Palpitations presented in 74% of patients, abnormal EKG found in 93.5% of patients, 33.3% segments were affected and most commonly in the mid-ventricular and apical segments, 84% of patients had > or = 2 affected segments. Right ventricle was affected in 2 patients. Left ventricular thrombi were detected in 3 patients. LVEF was 37.2% +/- 16.5% (14% - 70%), N/C was 3.6 +/- 1.4 (2.2 - 9.2) and C/VS was 0.43 +/- 0.11 (0.27 - 0.69).
Cardiac MRI allows accurate LVNC assessment.
No preview · Article · Dec 2006 · Zhonghua xin xue guan bing za zhi [Chinese journal of cardiovascular diseases]