Quantification of myocardial fibrosis using noninvasive T2-mapping magnetic resonance imaging: Preclinical models of aging and pressure overload

Noninvasive imaging of cardiac fibrosis is important for early diagnosis and intervention in chronic heart diseases. Here, we investigated whether noninvasive, contrast agent-free MRI T₂-mapping can quantify myocardial fibrosis in preclinical models of aging and pressure overload. Myocardial fibrosis and remodeling were analyzed in two animal models: (i) aging (15-month-old male CF-1 mice vs. young 6- to 8-week-old mice), and (ii) pressure overload (PO; by transverse aortic constriction in 4- to 5-month-old male C57BL/6 mice vs. sham-operated for 14 days). In vivo T₂-mapping was performed by acquiring data during the isovolumic and early diastolic phases, with a modified respiratory and ECG-triggered multiecho TurboRARE sequence on a 7-T MRI. Cine MRI provided cardiac morphology and function. A quantitative segmentation method was developed to analyze the in vivo T₂-maps of hearts at midventricle, apex, and basal regions. The cardiac fibrosis area was analyzed ex vivo by picro sirius red (PSR) staining. Both aged and pressure-overloaded hearts developed significant myocardial contractile dysfunction, cardiac hypertrophy, and interstitial fibrosis. The aged mice had two phenotypes, fibrotic and mild-fibrotic. Notably, the aged fibrotic subgroup and the PO mice showed a marked decrease in T₂ relaxation times (25.3 ± 0.6 in aged vs. 29.9 ± 0.7 ms in young mice, p = 0.002; and 24.3 ± 1.7 in PO vs. 28.7 ± 0.7 ms in shams, p = 0.05). However, no significant difference in T₂ was detected between the aged mild-fibrotic subgroup and the young mice. Accordingly, an inverse correlation between myocardial fibrosis percentage (FP) and T₂ relaxation time was derived (R² = 0.98): T₂ (ms) = 30.45 – 1.05 × FP. Thus, these results demonstrate a statistical agreement between T₂-map–quantified fibrosis and PSR staining in two different clinically relevant animal models. In conclusion, T₂-mapping MRI is a promising noninvasive contrast agent-free quantitative technique to characterize myocardial fibrosis.     

Case Report: Transient Stress Hyperglycemia in the Patient With ST-Elevation Myocardial Infarction

Transient stress hyperglycemia in the setting of acute myocardial infarction is a frequent phenomenon. Its transient nature should not dissuade the clinician from management of elevated blood glucose in a patient after an ST-elevation myocardial infarction. This case presents an adult patient after an ST-elevation myocardial infarction with transient stress hyperglycemia and the evidence used to identify optimal pharmacologic management and secondary prevention.     

DHS和PFNA固定治疗老年股骨粗隆间骨折的疗效

目的对比动力髋螺钉(dynamic hip screw,DHS)治疗和股骨近端抗旋髓内钉(proximal femoral nail anti-rotation,PFNA)固定治疗老年股骨粗隆间骨折疗效。方法纳入本院收治的45例采用PFNA固定治疗的老年股骨粗隆间骨折患者作为研究组,研究时间为2017年11月-2018年11月;回顾性分析2016年11月-2017年11月在我院采用DHS治疗的45例老年股骨粗隆间骨折患者的临床资料,作为对照组。记录两组的相关手术指标,观察手术并发症情况。结果研究组的手术时间和骨折愈合时间均短于对照组,术中出血量明显少于对照组,术后疼痛VAS评分均明显低于对照组(P<0.05)。对照组的并发症发生率高于研究组(P<0.05)。结论PFNA固定治疗比DHS治疗老年股骨粗隆间骨折更加安全有效,值得临床借鉴和应用。     

Long-Term Clinical Outcomes after Endovascular Therapy for Anti-Centromere Antibody-Positive Patients with Critical Limb-Threatening Ischemia

PurposeTo examine the long-term clinical outcomes of patients with anti-centromere antibody (ACA)-positive critical limb-threatening ischemia (CLTI) who were treated with endovascular therapy (EVT).Materials and MethodsThis was a retrospective analysis using a database of 423 consecutive CLTI patients (543 limbs, Rutherford class 4–6) who underwent EVT between January 2011 and March 2013. The patients were divided into 2 groups: an ACA-positive group (10 limbs, 8 patients) and a control group (46 limbs, 43 patients). The control group was defined as female, non-dialysis, and those who were able to obtain a below-knee angiogram.ResultsNone of the 8 ACA-positive CLTI patients had previously been diagnosed as ACA positive. No significant difference was observed in the below-the-knee lesion distribution and severity between the ACA-positive group and the control group. The median observational period was 51 months. The survival rate was 54% in the ACA-positive group and 76% in the control group at 5 years after EVT (P = .732). The freedom from major amputation rate was 60% in the ACA-positive group and 91% in the control group at 5 years after EVT (P = .029). The technical EVT success rate in the ACA-positive group was 70% (7/10). Of the successful EVT cases, 71% (5/7) of patients achieved complete wound healing or rest pain relief; however, 60% (3/5) had a recurrence of wounds.ConclusionsIn a series of ACA-positive patients with CLTI, successful EVT had acceptable outcomes with respect to wound healing with short-term results. However, the major amputation rate for ACA-positive patients was high in long-term follow-up.     

Discordant Electrocardiogram Left Ventricular Wall Thickness and Strain Findings in Influenza Myocarditis

A 42‐year‐old man presented with a viral prodrome and tested positive for influenza A. He rapidly deteriorated developing cardiogenic shock, rhabdomyolysis, and acute kidney injury. Patient improved 1 week later with supportive measures including vasopressors, inotropes, and an intraaortic balloon pump. We report this case as it highlights the discordance between echocardiographic ventricular wall thickening as a result of myocardial edema, and electrocardiographic findings at presentation, with a reversal in findings at time of resolution. Additionally, there was some suggestion of a regional pattern to the reduced longitudinal strain.