Surgery for aortic re-coarctation in children less than 10 years old. A single center experience in Siberia, Russia

Background: Persistence or recurrence of stenosis is a complication of initial coarctation repair. This study aims to report short-term outcomes of surgical management of recurrent coarctation and initial repair analysis. Methods: We retrospectively reviewed our experience with 51 patients undergoing recoarctation surgical repair between 2008 and 2019 using antegrade cerebral perfusion technique. Results: Surgical correction included prosthetic patch aortoplasty in 23 (45%), resection with wide end-to-end anastomosis in 15 (29%) and a tube interposition graft in 13 (25%) patients. Median age at initial correction and reintervention were 12 month and 9 years. Median interval from primary repair to reintervention was 60 months. Initial repair analysis revealed 33% of patients had initial correction in the neonatal period, 72,5% of patients were done via a left thoracotomy approach and 63% of patients had end-to-end anastomosis at initial surgery. Conclusion: Our study demonstrates that surgical repair of recurrent coarctation of the aorta using antegrade cerebral perfusion technique can be performed safely and with excellent results.

Feasibility of arterial spin labeling in evaluating high- and low-flow peripheral vascular malformations: a case series

We present a case series highlighting a novel use of arterial spin labeling (ASL), a MRI perfusion technique, to evaluate both high- and low-flow peripheral vascular malformations (PVMs) across a range of anatomical locations. While the role of ASL in assessing intracranial vascular malformations is more established, there is limited evidence for PVMs. Our results provide preliminary evidence for the feasibility of ASL in imaging PVMs and its potential ability to distinguish between high- and low-flow PVMs. In addition, we demonstrate its ability to identify focal high blood flow, which may indicate the nidus in arteriovenous malformations. Together, these findings have important implications for patient management. We also outline the potential benefits and limitations of ASL in the imaging of PVMs, and provide justification for further validation of its diagnostic performance.

Oleacein Intestinal Permeation and Metabolism in Rats Using an In Situ Perfusion Technique

Oleacein (OLEA) is one of the most important phenolic compounds in extra virgin olive oil in terms of concentration and health-promoting properties, yet there are insufficient data on its absorption and metabolism. Several non-human models have been developed to assess the intestinal permeability of drugs, among them, single-pass intestinal perfusion (SPIP), which is commonly used to investigate the trans-membrane transport of drugs in situ. In this study, the SPIP model and simultaneous luminal blood sampling were used to study the absorption and metabolism of OLEA in rats. Samples of intestinal fluid and mesenteric blood were taken at different times and the ileum segment was excised at the end of the experiment for analysis by LC–ESI–LTQ–Orbitrap–MS. OLEA was mostly metabolized by phase I reactions, undergoing hydrolysis and oxidation, and metabolite levels were much higher in the plasma than in the lumen. The large number of metabolites identified and their relatively high abundance indicates an important intestinal first-pass effect during absorption. According to the results, OLEA is well absorbed in the intestine, with an intestinal permeability similar to that of the highly permeable model compound naproxen. No significant differences were found in the percentage of absorbed OLEA and naproxen (48.98 ± 12.27% and 43.96 ± 7.58%, respectively).

Two-volume Dynamic CT Pulmonary Perfusion: Contrast Timing Optimization

Purpose: To develop and validate an optimal timing protocol for a low-radiation-dose CT pulmonary perfusion technique using only two volume scans.Methods: A total of 24 swine (48.5±14.3 kg) underwent contrast-enhanced dynamic CT. Multiple contrast injections were made under different pulmonary perfusion conditions, resulting in a total of 147 complete pulmonary arterial input functions(AIFs). Using all the AIF curves, an optimal contrast timing protocol was developed for a first-pass, two-volume dynamic CT perfusion technique (one at the base and the other at the peak of AIF curve). A subset of 14 swine with 70 CT acquisitions were used to validate the prospective timing protocol. The prospective two-volume perfusion measurements were quantitatively compared to the previously validated retrospective perfusion measurements with t-test, linear regression and Bland-Altman analysis. Results: The pulmonary artery time-to-peak ( Tpa) was related to one-half of the contrast injection duration( Tinj/2) by Tpa = 1.06 Tinj/2 + 0.90 (r=0.97). The prospective two-volume perfusion measurements (P­­PRO) were related to the retrospective measurements (PRETRO) by PPRO=0.87PRETRO+0.56 (r=0.88). The CT dose index and size-specific dose estimate of the two-volume CT technique were estimated to be 28.4 and 47.0mGy, respectively. Conclusion: The optimal timing protocol can enable an accurate, low-radiation-dose two-volume dynamic CT perfusion technique.

The potentiality of arterial spins labeling (ASL) magnetic resonance perfusion technique for the diagnosis of glioblastoma residual tissue

Background: Growing glioblastoma is associated with an impairment of the blood brain barrier and increased hemodynamic parameters (CBV, CBF), which is related to advanced tumor angiogenesis. Arterial spin labeling (ASL) perfusion, an additional study to the routine intravenous contrast-enhanced magnetic resonance imaging (MRI), may be a technique for assessment of hemodynamics and identification of the residual tumor tissue.Aim: To study the potential of native ASL to assess hemodynamic parameters and detect residual tumor tissue in the patients who had undergone surgical resection of glioblastoma.Materials and methods: At 2 to 4 weeks after surgery for glioblastoma grade IV, brain MRI with native ASL perfusion and subsequent intravenous contrast enhancement was performed in 63 patients. Cerebral blood flow (CBF) values were measured in three areas of interest: in the presumptive tumor tissue (PTT) with maximal perfusion, in the postoperative scar tissue (PST) and in the deep white matter (DWM) of the contralateral hemisphere.Results: According to their CBF values, all patients were categorized into two groups. Group 1 included 43 patients (68.3%) with mean CBF in PTT of 135.4±41.3 ml/100 Gr/min (min 73.9, max 255.9). These values were 5 to 6-fold higher than the CBF values in the PST and 6 to 8-fold higher than those in DWM. Group 2 included 20 patients (31.7%) without any areas of abnormal CBF increase in PST, with its mean value of 22.1±5.6 ml/100 Gr/min (min 13.9, max 37.1), which was close to the CBF level in DWM (19.8±4.6 ml/100 Gr/min, p=0.06). There were no between-group differences for the CBF values in PST (p=0.6), and DWM (p=0.7).Conclusion: ASL MR perfusion technique has good potential for the identification of residual tumor tissue after surgical resection of glioblastoma and can be an alternative to contrast enhancement during long-term follow up.

Two-Volume Dynamic CT Pulmonary Perfusion: Contrast Timing Optimization

PurposeTo develop and validate an optimal timing protocol for a low-radiation-dose CT pulmonary perfusion technique using only two volume scans.MethodsA total of 24 swine (48.5 ± 14.3 kg) underwent contrast-enhanced dynamic CT. Multiple contrast injections were made under different pulmonary perfusion conditions, resulting in a total of 147 complete pulmonary arterial input functions(AIF). Using the AIFs, an optimal timing protocol for acquisition of two-volume scans was developed for the first-pass CT perfusion technique. Specifically, the first volume scan was obtained at the base of the AIF using bolus-tracking and the second volume scan was obtained at the peak of the AIF using a time-to-peak relation derived by regression analysis. Additionally, a subset of 14 swine with 60 CT acquisitions were used to validate the prospective timing protocol. The prospective perfusion measurements using the two-volume scans, were quantitatively compared to the retrospective perfusion measurements using the entire AIF with t-test, linear regression and Bland-Altman analysis. The CT dose index(CTDI32vol) and size-specific dose estimate(SSDE) of the two-volume perfusion technique were also determined.ResultsThe pulmonary artery time-to-peak (TPA) was related to one-half of the contrast injection duration(TInj/2) by TPA = 1.06 TInj/2+0.090 (r=0.97). Simulated prospective two-volume perfusion measurements (P­­PRO) in ml/min/g were related to the retrospective measurements (PRETRO) by PPRO= 0.87PRETRO + 0.56 (r=0.88). The CTDI32vol and SSDE of the two-volume CT technique were estimated to be 28.4 and 47.0mGy, respectively.ConclusionThe optimal timing protocol can enable an accurate, low-radiation-dose two-volume dynamic CT perfusion technique.

Reply to “Comment on López-Yerena et al. ‘Absorption and Intestinal Metabolic Profile of Oleocanthal in Rats’ Pharmaceutics 2020, 12, 134”

Recently, in February 2020, we published a study exploring the intestinal absorption and metabolism of oleocanthal (OLC) in rats. A single-pass intestinal perfusion technique (SPIP) was used, involving simultaneous sampling from the luminal perfusate and mesenteric blood. Later, comments on our published paper were released, requesting clarification of specific data. In this detailed reply, we hope to have addressed and clarified all the concerns of A. Kaddoumi and K. El Sayed and that the scientific community will benefit from both the study and the comments it has generated.

Abstract 16959: A Youthful Cardiomyocyte Phenotype Drives Enhanced Cardiac Recovery in Adult Spiny Mice

Introduction: Adult mammals, including humans, experience limited recovery following myocardial infarction (MI). Recently, our group has uncovered a unique ability for enhanced cardiac recovery in adult spiny mice ( Acomys ). Methods and Results: Our preliminary studies have established appropriate similarities in heart structure and coronary anatomy between Acomys and Mus . Following the same permanent left artery descending (LAD) ligation surgery, Acomys and Mus showed a similar degree of early cardiac injury. Echocardiography and histological analyses showed more robust cardiac recovery and smaller scar area in Acomys . Moreover, Acomys exhibited a higher survival rate compared to Mus with no evidence of cardiac rupture or hypertrophy (measured by increasing heart/body weight) after MI. To investigate the mechanisms underlying this phenomenon, we isolated and quantified the size, nuclei number, and ploidy of adult cardiomyocytes (CMs) in both species (n=5 animals/group) using the Langendorff perfusion technique. Acomys CMs are significantly smaller in size compared to Mus and Acomys hearts have higher percentage of mononucleated cardiomyocytes. Using flow cytometry, we found that Acomys possess a higher percentage of diploid CMs compared to Mus . A closer examination of cardiomyocytes using electrophysiology revealed the presence of a T-type calcium current in adult Acomys CMs; a characteristic which is usually found in highly proliferative embryonic ventricular cardiomyocytes. Lastly, Acomys CMs demonstrated higher proliferative rates after injury compared to Mus . Conclusion: Taken together, our data provide strong evidence for enhanced cardiac repair in an adult mammalian model. Our results strongly suggest that Acomys maintain proliferative adult cardiomyocytes as adults and thus provide a cellular mechanism for their enhanced cardiac recovery after AMI.