P3359Myocardial flow reserve using 13N ammonia PET for detection of cardiac allograft vasculopathy in heart transplant patients

Purpose

Risk stratification and early detection of cardiac allograft vasculopathy (CAV) are essential in heart transplantation patients. CAV is associated with poor outcome in the chronic phase after heart transplantation. CAV presents a diffuse vascular involvement and has been difficult to noninvasively diagnose by the lack of a sensitive method to detect developing vascular pathology in the allograft. The present study investigates the ability of 13N-ammonia PET for detection of CAV in heart transplant patients.

Methods

Data of adenosine-stress 13N-ammonia PET imaging for thirty-one patients (mean age, 39 years-old) after 11 + 7 years from transplant was analyzed. Five patients had undergone percutaneous coronary intervention (PCI), and the remaining 26 patients had no history of definite myocardial ischemia. Myocardial flow was generated from the time activity curve of left ventricle input and myocardial uptake using 3-compartment model and the first 2 minutes' dataset of list-mode acquisition. Global - myocardial flow reserve (MFR) was calculated by stress to rest flow ratio. Patient with global-MFR <2.0 was defined as significant decrease. Summed difference score (SDS) was used as an estimate for the extent of ischemia, and the patient showing SDS >2 was identified as those having significant ischemia.

Results

The mean Global-MFR of our subjects were 2.3 (1.2 to 3.9). MFR using 13N-ammonia PET significantly decreases in one third of heart transplant patients in chronic stage. Eleven patients with Global-MFR <2.0 (35%) were observed, and eight of them had no history of clinical myocardial ischemia. The proportion of patients with a history of PCI is 18% in patients with Global-MFR <2.0 (vs 5%, p=0.210). Moreover, there were eight patients with SDS >2 (26%) including three patients having a history of PCI. The proportion of patients with a history of PCI tends to be high with SDS >2 (38% vs 9%, p=0.056).

Conclusion

This modality using 13N ammonia PET is useful for easily detection of CAV before manifestation of symptomatic myocardial ischemia in heart transplant patients.

Reliability of diagnosing acute ischemic cerebrovascular on magnetic resonance imaging disorders using iPads

PURPOSE

The use of tablet terminals has been explored in various medical settings; however, caution should be exercised when performing image diagnosis using this technology. The present study examined the characteristics of an iPad Air™ monitor and assessed radiographic image interpretations to verify the reliability of the telediagnosis of acute cerebral infarction based on magnetic resonance imaging (MRI) using a tablet terminal.

MATERIALS AND METHODS

The luminance of the iPad Air™ was measured using a UA-10 analyzer, and radiographic image interpretation experiments were performed in 100 patients who underwent MRI within 6 h of symptom onset. Ten physicians viewed the images on the iPad Air™ and a medical monitor, with an interval of 2 months between each interpretation.

RESULTS

When the iPad Air™ screen was pure white, the contour lines revealed nonuniform luminance distribution. In the reading experiment, the areas under the curve of the medical monitor and the iPad Air™ were 0.9311 and 0.9431, respectively. No significant difference was observed between the medical monitor and the iPad Air™ (p = 0.113).

CONCLUSION

The results of the observer performance studies for detecting acute ischemic cerebrovascular disorders on an iPad Air™ were found to be similar to those on a medical monitor.

Gastrointestinal perforation during treatment with erlotinib plus bevacizumab in two patients with non-small cell lung cancer exhibiting epidermal growth factor receptor mutations: A case report

A previous randomized phase II study in patients with non-small cell lung cancer (NSCLC) identified that combination treatment with erlotinib plus bevacizumab prolonged progression-free survival compared with erlotinib alone. However, combination bevacizumab and erlotinib treatment generally increased the risk of severe adverse events, including hemorrhage, thrombosis, fistula formation and gastrointestinal perforation. The present report describes two patients with NSCLC harboring epidermal growth factor receptor (EGFR) mutations, who experienced gastrointestinal perforation associated with erlotinib plus bevacizumab combination therapy. The first patient, a 67-year-old male with stage IIIB lung adenocarcinoma harboring a L858R point mutation in EGFR exon 21, received concurrent chemoradiotherapy. However, seven months later, the patient experienced a relapse and was administered erlotinib plus bevacizumab treatment. A total of two months subsequent to commencing treatment, the patient developed a perforated duodenal ulcer. The second patient, a 66-year-old male with lung adenocarcinoma harboring a deletion in EGFR exon 19 and multiple pulmonary metastases, demonstrated a partial response to erlotinib plus bevacizumab treatment. A total of seven months subsequent to starting treatment, the patient experienced lower abdominal pain, and abdominal computed tomography confirmed a diagnosis of colocutaneous fistula complicating sigmoid diverticulitis. Following repair of the perforation, both patients were restarted on erlotinib treatment alone. Gastrointestinal perforation may be a potentially severe adverse event of erlotinib plus bevacizumab combination therapy, even in the absence of tumor metastasis in the abdomen.

Wheezing and dyspnoea caused by aberrant left innominate artery

We present a rare case of a branching anomaly of the aortic arch that resulted in wheezing and dyspnoea. The patient was a 60‐year‐old male with severe wheezing from babyhood, originally diagnosed with severe bronchial asthma. On auscultation, the inspiratory and expiratory wheezes appeared when the patient leaned forward. He also had difficulty in swallowing solid mass. Tests for airway reversibility and hyperresponsiveness were negative, and asthma treatment was ineffective. He had a right aortic arch. A barium oesophagogram and endoscopic examination indicated narrowing of the oesophagus from behind. Three‐dimensional reconstruction of enhanced chest CT images indicated a right aortic arch and an aberrant enlarged left innominate artery, which compressed and narrowed the oesophagus and trachea from behind. Although the patient had been diagnosed with intractable bronchial asthma, his symptoms were more likely caused by this mechanical narrowing as wheezing and dyspnoea disappeared completely after total aortic arch replacement operation.

Mobility Changes in the First TMT Joint after Proximal First Metatarsal Osteotomy for Hallux Valgus Evaluated by Weightbearing CT and a 3D Analysis System

Category:

Bunion

Introduction/Purpose:

In a previous study, we found that feet with hallux valgus show significantly greater three-dimensional mobility than normal feet in all joints of the first ray. Displacement was particularly pronounced in the first TMT joints, indicating that this is the primary cause of first ray hypermobility. We developed a plate used specifically for proximal first metatarsal osteotomy to perform three-dimensional correction of hallux valgus and associated deformities. In this study, we evaluated changes in mobility of the first TMT joints after surgery in 3D using weightbearing CT.

Methods:

The subjects were 5 feet of 5 female patients with hallux valgus (mean age 56 years, mean hallux valgus angle 38°). We performed non-weightbearing and weightbearing (using a load equivalent to body weight) CT scans before surgery using an original loading device (Fig a). We reconstructed 3D models from captured images by segmentation and defined axial coordinate system (Fig b). Next, we measured the three-dimensional displacement of the first metatarsal bone relative to the medial cuneiform bone under weightbearing conditions. At 1 to 1.5 years after proximal metatarsal osteotomy for all patients, we performed a follow-up CT scans using the same method and compared preoperative and postoperative displacement. Student’s t- test was performed to statistically compare data and statistical significance was set at p < 0.05.

Results:

Postoperatively (when performing a follow up CT), the mean hallux valgus angle improved from 38° to 10° and the mean first-second metatarsal angle improved from 23° to 7°. The mean score on the Japanese Society for Surgery of the Foot hallux scale improved from 62 points to 97 points. Displacement of the first metatarsal bone relative to the medial cuneiform bone between non-weightbearing and weightbearing conditions decreased significantly in all directions, from 4.2° ± 1.8° to 1.6° ± 1.1° of dorsiflexion (p = 0.02), 4.9° ± 1.8° to 0.7° ± 0.9° of inversion (p = 0.001), and 4.4° ± 1.9° to 1.7° ± 0.8° of adduction (p = 0.01).

Conclusion:

Displacement of the first TMT joints under weightbearing conditions decreased after our surgery. This indicates that the surgery corrected hallux valgus and associated pes planus and produced favorable functional outcomes by improving the shape of the foot and hypermobility of the first ray through correction of the orientation and tension of surrounding tendons and ligaments and the plantar aponeurosis. In the future, we plan to further examine the pathology and treatment of hallux valgus with a focus on postoperative changes in soft tissue orientation.

Quantitative and Qualitative Change of Collagen of Achilles Tendons in Rats With Systemic Administration of Glucocorticoids

BACKGROUND

It is unclear whether glucocorticoid (GC) therapy is directly related to Achilles tendon rupture (ATR), because many of the reported patients were receiving long-term GC therapy for underlying diseases. This study aimed to elucidate the mechanism by which systemic GC administration causes weakening of the Achilles tendon by biochemically, mechanically, and morphologically evaluating quantitative and qualitative changes in collagen.

METHODS

Male 8-week-old mice were subcutaneously treated with either prednisolone (10 mg/mL/kg; GC group) or saline (1 mL/kg; control group) for 8 weeks and then subjected to the following experiments: (1) a tensile strength test; (2) quantification of the gene expressions of type 1 collagen and lysyl oxidase; (3) quantification of collagen content, enzymatic crosslinks (immature + mature), and senescent crosslinks; and (4) measurement of collagen fiber diameter by electron microscopy.

RESULTS

The maximum tensile load and gene expressions of type 1 collagen and lysyl oxidase were decreased in the GC group. Collagen content was significantly decreased in the GC group compared with the control group. The content of enzymatic crosslinks was significantly lower in the GC group than in the control group. The corresponding amount of senescent crosslinks was not significantly different. The mean collagen fiber diameter was significantly smaller in the GC group than in the control group. Histogram analysis showed a decreased number of thick fibers and an increased number of thin fibers in the GC group.

CONCLUSION

These observations suggest that systemic GC administration causes decreased strength of the Achilles tendon by decreasing its collagen content, hindering the formation of enzymatic crosslinks and thereby keeping collagen fibers in an immature state with smaller diameters.

CLINICAL RELEVANCE

This animal study showed that systemic GC administration directly prevents maturation of tendon collagen fibers and decreases tendon strength, regardless of the presence or absence of underlying disease.

Anti-sympathetic action enhances statin's pleiotropic effects: the combined effect of rosuvastatin and atenolol on endothelial function

AIM

Assessment of flow-mediated dilation (FMD) and nitroglycerin-mediated dilation (NMD) in the brachial artery by a new device (UNEXEF18G) has been reported to be excellent for evaluating endothelial function, and sympathetic overdrive can accelerate the atherosclerotic process. The purpose of this study was to investigate and confirm whether anti-sympathetic beta-blocking action can enhance the pleiotropic effects of statins.

METHODS

FMD and NMD were measured using the UNEXEF18G before and after 4-week treatment of rosuvastatin (5 mg/day) with or without atenolol (25 mg/day) in 44 hypercholesterolemic patients (70±8 years old, LDL-C >140 mg/dL) with hypertension. Patients were randomly allocated to two treatment arms: rosuvastatin alone (R-group, N.=22) and rosuvastatin with atenolol (RA-group, N.=22).

RESULTS

Baseline FMD was not different between the two treatment arms, and both groups showed improvement in FMD (R-group, 3.48±1.9% to 4.65±2.41%, P<0.05; RA-group, 3.42±1.48% to 5.46±1.79%, P<0.05), while there were no differences in NMD. The effects on lipid profiles were identical in the two groups. In addition, FMD improvement was greater in the RA-group than in the R-group (Δchange 2.15±1.29% vs. 1.16±1.15%, P<0.05).

CONCLUSION

Beta-blockade enhances the pleiotropic effects of statins on endothelial function. The mechanism should be confirmed by further studies.