Prognostic Value of Left Ventricular Longitudinal Function and Myocardial Fibrosis in Patients With Ischemic and Non-Ischemic Dilated Cardiomyopathy Concomitant With Type 2 Diabetes Mellitus: A 3.0 T Cardiac MR Study.

BACKGROUND: Poorly controlled type 2 diabetes mellitus (T2DM) is known to result in left ventricular (LV) dysfunction, myocardial fibrosis, and ischemic/nonischemic dilated cardiomyopathy (ICM/NIDCM). However, less is known about the prognostic value of T2DM on LV longitudinal function and late gadolinium enhancement (LGE) assessed with cardiac MRI in ICM/NIDCM patients. PURPOSE: To measure LV longitudinal function and myocardial scar in ICM/NIDCM patients with T2DM and to determine their prognostic values. STUDY TYPE: Retrospective cohort. POPULATION: Two hundred thirty-five ICM/NIDCM patients (158 with T2DM and 77 without T2DM). FIELD STRENGTH/SEQUENCE: 3T; steady-state free precession cine; phase-sensitive inversion recovery segmented gradient echo LGE sequences. ASSESSMENT: Global peak longitudinal systolic strain rate (GLPSSR) was evaluated to LV longitudinal function with feature tracking. The predictive value of GLPSSR was determined with ROC curve. Glycated hemoglobin (HbA1c) was measured. The primary adverse cardiovascular endpoint was follow up every 3 months. STATISTICAL TESTS: Mann-Whitney U test or student's t-test; Intra and inter-observer variabilities; Kaplan-Meier method; Cox proportional hazards analysis (threshold = 5%). RESULTS: ICM/NIDCM patients with T2DM exhibited significantly lower absolute value of GLPSSR (0.39 ± 0.14 vs. 0.49 ± 0.18) and higher proportion of LGE positive (+) despite similar LV ejection fraction, compared to without T2DM. LV GLPSSR was able to predict primary endpoint (AUC 0.73) and optimal cutoff point was 0.4. ICM/NIDCM patients with T2DM (GLPSSR < 0.4) had more markedly impaired survival. Importantly, this group (GLPSSR < 0.4, HbA1c ≥ 7.8%, or LGE (+)) exhibited the worst survival. In multivariate analysis, GLPSSR, HbA1c, and LGE (+) significantly predicted primary adverse cardiovascular endpoint in overall ICM/NIDCM and ICM/NIDCM patients with T2DM. CONCLUSIONS: T2DM has an additive deleterious effect on LV longitudinal function and myocardial fibrosis in ICM/NIDCM patients. Combining GLPSSR, HbA1c, and LGE could be promising markers in predicting outcomes in ICM/NIDCM patients with T2DM. EVIDENCE LEVEL: 3 TECHNICAL EFFICACY: 5.

Dynamic changes in cardiac morphology, function, and diffuse myocardial fibrosis duration of diabetes in type 1 and type 2 diabetic mice models using 7.0 T CMR and echocardiography.

Background: Diabetes mellitus (DM) is associated with an increased risk of cardiovascular disease (CVD). Hence, early detection of cardiac changes by imaging is crucial to reducing cardiovascular complications. Purpose: Early detection of cardiac changes is crucial to reducing cardiovascular complications. The study aimed to detect the dynamic change in cardiac morphology, function, and diffuse myocardial fibrosis(DMF) associated with T1DM and T2DM mice models. Materials and methods: 4-week-old C57Bl/6J male mice were randomly divided into control (n=30), T1DM (n=30), and T2DM (n=30) groups. A longitudinal study was conducted every 4 weeks using serial 7.0T CMR and echocardiography imaging. Left ventricular ejection fraction (LV EF), tissue tracking parameters, and DMF were measured by cine CMR and extracellular volume fraction (ECV). Global peak circumferential strain (GCPS), peak systolic strain rate (GCPSSR) values were acquired by CMR feature tracking. LV diastolic function parameter (E/E') was acquired by echocardiography. The correlations between the ECV and cardiac function parameters were assessed by Pearson's test. Results: A total of 6 mice were included every 4 weeks in control, T1DM, and T2DM groups for analysis. Compared to control group, an increase was detected in the LV mass and E/E' ratio, while the values of GCPS, GCPSSR decreased mildly in DM. Compared to T2DM group, GCPS and GCPSSR decreased earlier in T1DM(GCPS 12W,P=0.004; GCPSSR 12W,P=0.04). ECV values showed a significant correlation with GCPS and GCPSSR in DM groups. Moreover, ECV values showed a strong positive correlation with E/E'(T1DM,r=0.757,P<0.001;T2DM, r=0.811,P<0.001). Conclusion: The combination of ECV and cardiac mechanical parameters provide imaging biomakers for pathophysiology, early diagnosis of cardiac morphology, function and early intervention in diabetic cardiomyopathy in the future.

Stented elephant trunk procedure with left subclavian artery transposition for acute type B dissection with distal arch involvement.

OBJECTIVE: Complete or partial supra-aortic debranching, after thoracic endovascular aortic repair, is appealing treatment for complicated acute type B dissection (ABAD) with aortic arch involvement (AAI) because of reduced surgical trauma. However, unsatisfactory outcomes have been reported. We retrospectively reviewed our experience of left subclavian artery (LSCA) transposition with stented elephant trunk (SET) implantation for complicated ABAD with distal AAI. METHODS: From April 2011 to December 2014, 19 patients (all men; mean age: 44 years) who had complicated ABAD and distal AAI underwent LSCA transposition with SET implantation via a median sternotomy under hypothermic cardiopulmonary bypass with selective cerebral perfusion. Preoperative renal dysfunction was observed in 3 patients, visceral ischemia in 2 patients, and lower-limb ischemia in 1 patient. RESULTS: No in-hospital deaths occurred. Seventeen patients required mechanical ventilation for <24 hours, and 2 cases for <48 hours. The mean time of mechanical ventilation and duration of stay in the intensive care unit was 18 ± 6 hours and 44 ± 16 hours, respectively. Ischemia of the viscera and lower limbs after surgery was ameliorated. Continuous renal replacement therapy was not required in 3 patients who had preoperative renal dysfunction. Complete thrombosis of the false lumen at the distal end of the SET was observed in 17 of 18 (94.4%) patients during follow-up. CONCLUSIONS: This method preserves autologous brachiocephalic vessels, excludes the false lumen, promotes thrombosis and remodeling of the distal aorta, and repairs proximal aortic lesions simultaneously. Satisfactory surgical outcomes and follow-up results were achieved using LSCA transposition with SET implantation.

Surgery for acute type A dissection using total arch replacement combined with stented elephant trunk implantation: Preservation of autologous brachiocephalic vessels.

OBJECTIVE: Various techniques have been introduced to treat acute type A dissection during aortic arch reconstruction. We retrospectively reviewed our experience of total arch replacement, with implantation of a stented elephant trunk, using preservation of autologous brachiocephalic vessels in patients with acute type A dissection. METHODS: Between August 2011 and April 2013, 20 patients (16 men, 4 women; mean age, 45 ± 10 years, range, 24-62 years) with acute type A dissection underwent total arch replacement combined with stented elephant trunk implantation, using preservation of autologous brachiocephalic vessels under hypothermic cardiopulmonary bypass with selective antegrade cerebral perfusion. RESULTS: No in-hospital deaths occurred. A transient neurologic deficit occurred in 1 patient, who ultimately required tracheotomy. Reoperation was indicated in 1 patient for bleeding. All patients survived and were discharged. During the mean follow-up period of 26 ± 7 months, 1 patient underwent thoracoabdominal aortic replacement, and 1 patient was lost to follow up. The patency of the anastomotic site between the left subclavian artery and the left common carotid artery was confirmed on computed tomography scanning. CONCLUSIONS: This technique simplified hemostasis and anastomosis, reduced the size of the residual aortic wall, and preserved the autologous brachiocephalic vessels, yielding satisfactory surgical results. This technique is an alternative approach for suitable patients with acute type A dissection. However, outcomes are preliminary, and long-term follow up is required.

Complications of open stent-graft in treatment of aortic dissection.

Open stent-graft has been used in the treatment of aortic dissection in recent years. Two device related complications happened in two patients. One was stenosis of the true lumen in the descending aorta caused by infolding of the distal end of the stent-graft immediately after its deployment. The other one was a new intima tear at the distal end of the stent-graft caused by full expansion of the stent-graft two years after stent-graft implantation. With the refinement of the device and enrichment of surgeons' experience, such complications could be avoided in the future.

Bolus shaping of contrast medium to adapt k-space sampling: adjusting injection protocol of magnetic resonance angiography for optimal images in a 3-T system.

PURPOSE: To explore the possibility of shaping bolus of contrast medium to adapt k-space sampling to improve image quality in a 3-T system. MATERIALS AND METHODS: Eighty patients suspected of having renal arterial disease or atherosclerosis were divided into four groups and underwent imaging with different high-spatial-resolution three-dimensional contrast-enhanced magnetic resonance angiography (MRA) scanning and injection protocol combinations. A group of 20 patients were injected single-dose contrast medium with a centric view ordering for k-space filling. Another group of 20 patients underwent MRA with double-dose and centric-view ordering. The bolus of contrast medium was shaped by adjusting injection protocol to adapt centric and sequential view ordering of sampling k-space, respectively, for other two groups. Then, the quality of image got with different protocols combination was compared, and the dose of contrast medium used in latter two groups was compared with single- and double-dose prescription basing on body weight. RESULT: Bolus shaped adapting to centric view ordering and sequential view ordering brings more homogeneous vessel signal. Individualized dose is lower than the double dose but higher than the single dose. Dose does not necessarily correlate with body weight. CONCLUSION: Under certain scanning protocol, appropriate shape of contrast medium passing through target vessel leads to higher-quality image and save contrast medium.

Low injection rate for 3D moving-table bolus-chase MR angiography: initial experience with 3-T imaging to allay venous contamination in the calf.

OBJECTIVE: The purpose of this study was to evaluate the potential for improving the image quality of 3D bolus-chase peripheral MR angiography by injecting contrast medium at a slow rate. SUBJECTS AND METHODS: Using similar imaging parameters in all cases, we performed bolus-chase MR angiography of the abdominal and lower limb arteries of 80 patients. The injection protocol for 40 patients had three parts: 20 mL of gadopentetate dimeglumine at 2 mL/s, 8 mL of gadopentetate dimeglumine at 1 mL/s, and 20 mL of saline solution at 1 mL/s. For the other 40 patients, the injection protocol was 20 mL of gadopentetate dimeglumine at 1.2 mL/s, 8 mL of gadopentetate dimeglumine at 0.7 mL/s, and 20 mL of saline solution at 0.7 mL/s. Using independent Student's t tests between groups, we compared signal-to-noise and contrast-to-noise ratios in the abdomen and pelvis, the thigh, and the calf. Arterial visibility and venous contamination on 3D images of the calf were graded and compared. RESULTS: The lower injection rate increased arterial visibility (p < 0.001), reduced venous contamination in the calf (p < 0.001), and increased the contrast-to-noise ratio in the calf (p < 0.001). At the upper levels, signal-to-noise and contrast-to-noise ratios did not differ between the two groups. CONCLUSION: At 3-T MRI, a lower injection rate may alleviate venous contamination and increase arterial visibility in the calf while signal-to-noise and contrast-to-noise ratios at higher levels are maintained.

Endovascular repair after stent elephant trunk procedure for extensive thoracic aortic aneurysm.

Hybrid surgical-endovascular procedure was conducted in a 46-year-old male with extensive thoracic aortic aneurysm. Ascending aorta and arch replacement combined with stent elephant trunk implantation was performed first. An open stent-graft was implanted into the descending aorta. One month later, endovascular repair was conducted. Postoperative CTA showed total coverage of the descending aorta by stent-grafts and the descending aortic aneurysm was totally thrombo-excluded. Stent elephant trunk may be a better alternative to conventional elephant trunk in hybrid surgical-endovascular approaches in treatment of extensive thoracic aortic aneurysm.

A study of aortic dimension in type B aortic dissection.

Difference between arch diameter and true lumen diameter in the descending aorta was studied in patients with type B aortic dissection. The diameters of the aortic arch (Proximal ) and mid-descending aorta (Distal ) were measured on computer tomography angiography (CTA) in 20 healthy adults. Forty-two patients with type B aortic dissection who underwent endovascular repair were divided into two groups: an acute group (23 patients) and a chronic group (19 patients). The diameters of the arch (Proximal ) and the true lumen of the mid-descending aorta (Distal ) were measured on digital subtraction angiography (DSA) and CTA. The taper ratio was defined as (Proximal -Distal )/(Proximal )x100%. In the control group, the taper ratio was 13.0+/-4.7% on CTA. In the acute patients group, the taper ratio was 23.6+/-11.3% on DSA and 21.9+/-12.1% on CTA. In the chronic patients group, the taper ratio was 31.5+/-13.6% on DSA and 30.1+/-11.4% on CTA. In both acute and chronic type B aortic dissection, the aorta tapers significantly from arch to true lumen in the descending aorta. Stent-graft with tapered design may be a viable treatment option for endovascular repair of type B aortic dissection.

Carotid vulnerable lesions are related to accelerated recurrence for cerebral infarction magnetic resonance imaging study.

RATIONALE AND OBJECTIVES: We sought to test the hypothesis that magnetic resonance imaging (MRI)-defined vulnerable plaques correlate to accelerated reoccurrence of cerebrovascular events and to evaluate the potential use of MRI in secondary prevention of ischemic stroke. MATERIALS AND METHODS: Fifty-three symptomatic participants were recruited from patients sustaining their second MRI-confirmed cerebral infarction. Nine participants were women and 44 were men; the mean age was 69.2 years (range, 55-94 years). Patients were imaged within 7 days after the reoccurrence of cerebral infarction. The MRI diagnostic signals defined a classification of lesion type. We compare the interval between two cerebral infarctions with plaque vulnerability defined by the MRI lesion type. We used a Cox proportional hazards model to calculate the relationship between vulnerable lesions and the interval of cerebral infarction, and we followed these patients for 180 days and compared the recurrent rate for the third-time cerebral infarction between patients with and without vulnerable plaque. RESULTS: The mean infarction recurrence interval for patients with vulnerable lesions was shorter than the mean interval for patients without vulnerable lesion (310.1 versus 1697.2, P< .001). In patients with recurrent cerebral infarction within 1 year, vulnerable lesions were more frequently detected (76% versus 19%, P< .001). The patients with vulnerable lesions had an 8.8-fold higher hazard risk (8.8; P< .001, 95% confidence interval, 3.9-19.7) than those without vulnerable lesions after adjustment for risk factors. For those with vulnerable plaque, the morbidity of third-time cerebral infarction was higher than those without (24% versus 3%, P = .023). CONCLUSION: MRI-defined vulnerable lesions in carotid arteries are related to accelerated recurrent cerebral infarction and high recurrent rate. MRI demonstrates clinical value in the secondary prevention of cerebral infarction.