Supporting the Ross procedure: preserving root physiology while mitigating autograft dilatation.

PURPOSE OF REVIEW: The purpose of this article is to describe the optimized approach to nonrepairable aortic valve disease in young adults with a Ross procedure, while preserving the dynamic physiology of the aortic root. RECENT FINDINGS: As the techniques for supporting pulmonary autografts continue to be refined, and the applicability of the Ross procedure continues to expand, an assessment of the various techniques based on aortic root physiology is warranted. Semi-resorbable scaffolds show promise in ovine models for improving the Ross procedure. Recent long-term outcomes for the Dacron inclusion technique in comparison to more physiologic methods of support emphasize the importance of balancing the prevention of early dilatation with the preservation of root haemodynamics. As this review will synthesize, the dynamic physiology of the root may be preserved even in patients at a higher risk of autograft dilatation. SUMMARY: The favourable long-term outcomes of the Ross procedure can be partly attributed to the ability of the autograft to restore dynamism to the neoaortic root. Patient-specific modifications that respect root physiology can tailor the Ross procedure to address each patient's risk factors for early dilatation and late failure. As such, the Ross procedure should be recognized as an increasingly favourable solution for a wide spectrum of nonpreservable aortic valve disease in young adults.

Bracy procedure with ductal mucosal pancreaticogastrostomy and an internal stent for pancreatic complex deep injury: how to do it.

Pancreatic complex deep injury extending to the main pancreatic duct (MPD), caused by strong external forces such as traffic accidents, is lethal without emergency surgery. However, the best surgical procedure for this serious injury has not been established. The Bracey procedure is a relatively simple reconstructive technique involving pancreaticogastrostomy, but it is often followed by postoperative complications, such as dilatation of the MPD caused by anastomotic stenosis, as well as subsequent serious sequela such as repetitive pancreatitis and new-onset pancreatic diabetes. It is possible that the combination of ductal mucosal pancreaticogastrostomy (DMPG) and an internal stent might prevent anastomotic stenosis of the MPD. We found that the Bracey procedure was a safe and effective reconstructive procedure for five patients who suffered a pancreatic complex deep injury with MPD involvement. In three of these patients, postoperative dilatation of the MPD was prevented by combining the Bracey procedure with DMPG including an internal stent. Our experience suggests that this procedure is one of the best techniques for treating pancreatic complex deep injury extending to the MPD.

Flavanone-rich citrus beverages counteract the transient decline in postprandial endothelial function in humans: a randomised, controlled, double-masked, cross-over intervention study.

Specific flavonoid-rich foods/beverages are reported to exert positive effects on vascular function; however, data relating to effects in the postprandial state are limited. The present study investigated the postprandial, time-dependent (0-7 h) impact of citrus flavanone intake on vascular function. An acute, randomised, controlled, double-masked, cross-over intervention study was conducted by including middle-aged healthy men (30-65 years, n 28) to assess the impact of flavanone intake (orange juice: 128·9 mg; flavanone-rich orange juice: 272·1 mg; homogenised whole orange: 452·8 mg; isoenergetic control: 0 mg flavanones) on postprandial (double meal delivering a total of 81 g of fat) endothelial function. Endothelial function was assessed by flow-mediated dilatation (FMD) of the brachial artery at 0, 2, 5 and 7 h. Plasma levels of naringenin/hesperetin metabolites (sulphates and glucuronides) and nitric oxide species were also measured. All flavanone interventions were effective at attenuating transient impairments in FMD induced by the double meal (7 h post intake; P<0·05), but no dose-response effects were observed. The effects on FMD coincided with the peak of naringenin/hesperetin metabolites in circulation (7 h) and sustained levels of plasma nitrite. In summary, citrus flavanones are effective at counteracting the negative impact of a sequential double meal on human vascular function, potentially through the actions of flavanone metabolites on nitric oxide.

Combined laser in-situ keratomileusis and accelerated corneal cross-linking: an update.

PURPOSE OF REVIEW: The purpose is to review the literature of combined laser in-situ keratomileusis (LASIK) and accelerated corneal collagen cross-linking (CXL) in context of its indications-contraindications, kerato-refractive, visual and safety outcomes, particularly with reference to preventing the development of post-LASIK ectasia. RECENT FINDINGS: LASIK + accelerated CXL has been developed with the rationale that the addition of CXL after LASIK may strengthen the LASIK compromised corneal biomechanics and minimize the complications such as post-LASIK ectasia. Different clinical studies have documented the safety and efficacy of LASIK + accelerated CXL for the correction of myopia or hyperopia and in the patients with low predicted residual bed thickness. SUMMARY: Available literature shows that refractive and keratometric outcomes of LASIK + accelerated CXL are comparable or better than LASIK alone. Less regression has been observed after LASIK + accelerated CXL compared with LASIK alone and no case of post-LASIK ectasia development has been reported among 673 eyes with the follow-up ranging from 3 months to 4.5 years. Future studies with large numbers of patients and longer postoperative follow-ups are needed to establish the efficacy of LASIK + accelerated CXL in preventing the development of post-LASIK ectasia.

Frequency and risk factors for rebleeding events in patients with small bowel angioectasia.

BACKGROUND: Small bowel angioectasia is reported as the most common cause of bleeding in patients with obscure gastrointestinal bleeding. Although the safety and efficacy of endoscopic treatment have been demonstrated, rebleeding rates are relatively high. To establish therapeutic and follow-up guidelines, we investigated the long-term outcomes and clinical predictors of rebleeding in patients with small bowel angioectasia. METHODS: A total of 68 patients were retrospectively included in this study. All the patients had undergone CE examination, and subsequent control of bleeding, where needed, was accomplished by endoscopic argon plasma coagulation. Based on the follow-up data, the rebleeding rate was compared between patients who had/had not undergone endoscopic treatment. Multivariate analysis was performed using Cox proportional hazard regression model to identify the predictors of rebleeding. We defined the OGIB as controlled if there was no further overt bleeding within 6 months and the hemoglobin level had not fallen below 10 g/dl by the time of the final examination. RESULTS: The overall rebleeding rate over a median follow-up duration of 30.5 months (interquartile range 16.5-47.0) was 33.8% (23/68 cases). The cumulative risk of rebleeding tended to be lower in the patients who had undergone endoscopic treatment than in those who had not undergone endoscopic treatment, however, the difference did not reach statistical significance (P = 0.14). In the majority of patients with rebleeding (18/23, 78.3%), the bleeding was controlled by the end of the follow-up period. Multiple regression analysis identified presence of multiple lesions (≥3) (OR 3.82; 95% CI 1.30-11.3, P = 0.02) as the only significant independent predictor of rebleeding. CONCLUSION: In most cases, bleeding can be controlled by repeated endoscopic treatment. Careful follow-up is needed for patients with multiple lesions, presence of which is considered as a significant risk factor for rebleeding.

A modification of the pulmonary autograft procedure to prevent late autograft dilatation.

Although the pulmonary autograft procedure for aortic valve replacement is a commonly utilized option for children, its use is diminishing in adult-aged patients. One commonly cited concern is the tendency for the pulmonary autograft to dilate in the aortic position. This article reviews a technique we have used in 36 patients since October, 2004 that stabilizes the autograft so that it cannot dilate. There have been no operative or late deaths and the autograft has continued to function in 34 patients. Two patients have undergone autograft replacement because of early failure, which we believe was likely related to technical considerations in our early technique (first reported in the 2005 STCVS Pediatric Cardiac Surgery Annual). The technical modifications described in this article have produced a more reliable and reproducible technique and have not resulted in any autograft failures in our experience. One patient with Marfan's syndrome and a bicuspid aortic valve is symptom- and dilation-free 8 years post op, with no autograft or pulmonary homograft insufficiency, normal activity and a stable aortic root by serial echocardiography. Our results suggest that this technique might be applicable for selected adult patients in whom autograft growth is not necessary and for whom the risk of autograft dilatation would provide a reason to avoid a pulmonary autograft procedure.

Autologous intestinal reconstructive surgery to reduce bowel dilatation improves intestinal adaptation in children with short bowel syndrome.

OBJECTIVES: Intestinal failure (IF) is a common consequence of neonatal small bowel pathology. In our experience, bowel dilatation is often responsible for the IF state in patients who fail to adapt despite adequate residual bowel length. The aim of the present study was to investigate the role of surgery to reduce bowel dilatation, and thus favour PN independence, for these children. METHODS: Data were collected prospectively for all of the patients referred to our unit for a 7-year period (2004-2011). Eight patients (2 congenital atresia, 2 gastroschisis with atresia, 1 simple gastroschisis, 3 necrotising enterocolitis) with gut dilatation who failed adaptation despite a bowel length >40 cm were identified. Preoperatively, all patients were totally dependent on parenteral nutrition (PN). Patients were managed by longitudinal intestinal lengthening and tailoring (n = 3), serial transverse enteroplasty (n = 2), or tapering enteroplasty (n = 3). RESULTS: Median age at time of surgery was 273 days (103-1059). Mean gut length increased from 51 (35-75) to 73 cm (45-120) following surgery (P = 0.02). Incidence of sepsis (P = 0.01) and peak serum bilirubin levels (P = 0.005) were reduced postoperatively. PN was discontinued after a median of 110 days (35-537) for 7 patients; 1 patient remains on PN 497 days after surgery. CONCLUSIONS: These data indicate that reconstructive surgery to reduce bowel diameter may be an effective technique for treating IF in patients with short bowel syndrome, without sacrificing intestinal length. We suggest that this technique may reduce the need for bowel transplantation in this group of patients.

Comprehensive management of post-LASIK ectasia: From prevention to treatment.

Post-laser in situ keratomileusis (post-LASIK) ectasia (PLE) is one of the most serious complications after refractive surgery, mainly manifested as progressive thinning and trembling thinning of the cornea, accompanied by increased myopia and astigmatism. The mechanisms behind mainly include genetic risk factors and external environmental factors such as eye rubbing and cornea surgery. In order to achieve the goal of reducing the incidence of ectasia, preoperative screening strategies need to be continuously improved, through the collection and assessment of genetic and environmental risk factors. Although previous preoperative screening methods did not have a uniform standard, the emergence of artificial intelligence (AI) can help us process a large amount of information and make rational use of the data. By using high-fidelity finite element modelling, differences in preoperative and postoperative strain distributions can be observed, which can predict the risk of postoperative ectasia. In this review, we describe the incidence, aetiology, prevention and treatment of PLE for the purpose of comprehensive management. In terms of treatment, corneal collagen cross-linking has been widely used to treat progressive keratoconus and other ectasia disease, either as a preventive measure during surgery or as a therapeutic modality after surgery to prevent progression of corneal dilation. Although the standard Dresden protocol has been identified as the gold standard treatment for corneal dilatation, a series of refinements, investigations and long-term studies have been conducted in recent years. Thus, understanding the factors involved in delaying the onset and slowing progression of cornea ectasia will be key to reducing the incidence worldwide.

Pravastatin reduces Marfan aortic dilation.

BACKGROUND: The sequelae of aortic root dilation are the lethal consequences of Marfan syndrome. The root dilation is attributable to an imbalance between deposition of matrix elements and metalloproteinases in the aortic medial layer as a result of excessive transforming growth factor-beta signaling. This study examined the efficacy and mechanism of statins in attenuating aortic root dilation in Marfan syndrome and compared effects to the other main proposed preventative agent, losartan. METHODS AND RESULTS: Marfan mice heterozygous for a mutant allele encoding a cysteine substitution in fibrillin-1 (C1039G) were treated daily from 6 weeks old with pravastatin 0.5 g/L or losartan 0.6 g/L. The end points of aortic root diameter (n=25), aortic thickness, and architecture (n=10), elastin volume (n=5), dp/dtmax (maximal rate of change of pressure) (cardiac catheter; n=20), and ultrastructural analysis with stereology (electron microscopy; n=5) were examined. The aortic root diameters of untreated Marfan mice were significantly increased in comparison to normal mice (0.161 ± 0.001 cm vs 0.252 ± 0.004 cm; P<0.01). Pravastatin (0.22 ± 0.003 cm; P<0.01) and losartan (0.221 ± 0.004 cm; P<0.01) produced a significant reduction in aortic root dilation. Both drugs also preserved elastin volume within the medial layer (pravastatin 0.23 ± 0.02 and losartan 0.29 ± 0.03 vs untreated Marfan 0.19 ± 0.02; P=0.01; normal mice 0.27 ± 0.02). Ultrastructural analysis showed a reduction of rough endoplasmic reticulum in smooth muscle cells with pravastatin (0.022 ± 0.004) and losartan (0.013 ± 0.001) compared to untreated Marfan mice (0.035 ± 0.004; P<0.01). CONCLUSIONS: Statins are similar to losartan in attenuating aortic root dilation in a mouse model of Marfan syndrome. They appear to act through reducing the excessive protein manufacture by vascular smooth muscle cells, which occurs in the Marfan aorta. As a drug that is relatively well-tolerated for long-term use, it may be useful clinically.

Progesterone induced mesenchymal differentiation and rescued cystic dilation of renal tubules of Pkd1(-/-) mice.

Autosomal dominant polycystic kidney disease (ADPKD), the most common hereditary disease affecting the kidneys, is caused in 85% of cases by mutations in the PKD1 gene. The protein encoded by this gene, polycystin-1, is a renal epithelial cell membrane mechanoreceptor, sensing morphogenetic cues in the extracellular environment, which regulate the tissue architecture and differentiation. However, how such mutations result in the formation of cysts is still unclear. We performed a precise characterization of mesenchymal differentiation using PAX2, WNT4 and WT1 as a marker, which revealed that impairment of the differentiation process preceded the development of cysts in Pkd1(-/-) mice. We performed an in vitro organ culture and found that progesterone and a derivative thereof facilitated mesenchymal differentiation, and partially prevented the formation of cysts in Pkd1(-/-) kidneys. An injection of progesterone or this derivative into the intraperitoneal space of pregnant females also improved the survival of Pkd1(-/-) embryos. Our findings suggest that compounds which enhance mesenchymal differentiation in the nephrogenesis might be useful for the therapeutic approach to prevent the formation of cysts in ADPKD patients.

Carbon dioxide vs. air insufflation in ileo-colonoscopy and in gastroscopy plus ileo-colonoscopy: a comparative study.

INTRODUCTION: insufflation with carbon dioxide (CO2) during endoscopies compared to air is associated with a decrease in abdominal discomfort after the examination, because CO2 is readily absorbed through the small intestine and eliminated by the lungs. AIM: the objective of this randomized clinical trial was to assess the effect of CO2 insufflation on pain and abdominal distension after an ileo-colonoscopy (I) and after an ileo-colonoscopy plus gastroscopy (I+G). MATERIAL AND METHODS: we included a total of 309 patients in the study and all endoscopies were performed under sedation with propofol. Two hundred fourteen patients underwent an I (132 with CO2 / 82 with air) and 95 underwent an I+G (53 with CO2 / 42 with air). Abdominal pain was studied at 10, 30 and 120 minutes of exploration and abdominal perimeter difference before and after the procedure. RESULTS: both in group I and in group I+G, the use of CO2 translated into an average of abdominal pain significantly lower (p < 0.05). Similarly, a smaller increase in waist circumference was found among group I and group I+G, in patients where CO2 was used (p < 0.05). CONCLUSION: the insufflation of CO2 instead of air during the performance of endoscopy significantly reduces the discomfort and abdominal pain after an ileo-colonoscopy and after a gastroscopy + ileo-colonoscopy.

Impairment of endothelial protection by ischemic postconditioning in patients with major depressive disorder.

This study used a model of ischemia-reperfusion injury to the brachial artery endothelium to investigate whether the protective role of ischemic postconditioning (IPostC) is impaired in patients with major depressive episode. Flow-mediated dilation (FMD) was measured before and after ischemia-reperfusion in the absence or presence of IPostC in 24 patients with major depressive disorder and 20 healthy controls. In addition, the severity of the depression, as assessed by the Hamilton Depression Rating Scale (HDRS) and Beck Depression Inventory (BDI) scores, and plasma nitrogen dioxide (NO(x)) levels were also determined. Ischemia-reperfusion resulted in a significant decrease in FMD in both patients with a major depressive episode and healthy controls. IPostC effectively prevented this decrease in FMD in healthy controls, but not in patients with a major depressive episode. HDRS and BDI scores were markedly increased, but plasma NO(x) levels decreased, in patients with a major depressive episode compared with those in healthy controls. Correlation analysis showed that HDRS and BDI scores and plasma NO(x) levels were significantly associated with post-ischemia-reperfusion FMD. These results suggest that endothelial protection by IPostC is impaired in patients with major depressive disorder, which may be related to the decrease in endothelial nitric oxide production and the severity of the depression.

Krill oil attenuates left ventricular dilatation after myocardial infarction in rats.

BACKGROUND: In the western world, heart failure (HF) is one of the most important causes of cardiovascular mortality. Supplement with n-3 polyunsaturated fatty acids (PUFA) has been shown to improve cardiac function in HF and to decrease mortality after myocardial infarction (MI). The molecular structure and composition of n-3 PUFA varies between different marine sources and this may be of importance for their biological effects. Krill oil, unlike fish oil supplements, contains the major part of the n-3 PUFA in the form of phospholipids. This study investigated effects of krill oil on cardiac remodeling after experimental MI. Rats were randomised to pre-treatment with krill oil or control feed 14 days before induction of MI. Seven days post-MI, the rats were examined with echocardiography and rats in the control group were further randomised to continued control feed or krill oil feed for 7 weeks before re-examination with echocardiography and euthanization. RESULTS: The echocardiographic evaluation showed significant attenuation of LV dilatation in the group pretreated with krill oil compared to controls. Attenuated heart weight, lung weight, and levels of mRNA encoding classical markers of LV stress, matrix remodeling and inflammation reflected these findings. The total composition of fatty acids were examined in the left ventricular (LV) tissue and all rats treated with krill oil showed a significantly higher proportion of n-3 PUFA in the LV tissue, although no difference was seen between the two krill oil groups. CONCLUSIONS: Supplement with krill oil leads to a proportional increase of n-3 PUFA in myocardial tissue and supplement given before induction of MI attenuates LV remodeling.

The benefits of using selenium in the treatment of Chagas disease: prevention of right ventricle chamber dilatation and reversion of Trypanosoma cruzi-induced acute and chronic cardiomyopathy in mice.

Cardiac damage is a frequent manifestation of Chagas disease, which is caused by the parasite Trypanosoma cruzi. Selenium (Se) is an essential micronutrient, the deficiency of which has been implicated in the development of cardiomyopathy. Our group has previously demonstrated that Se supplementation prevents myocardial damage during acute T. cruzi infection in mice. In this study, we analyzed the effect of Se treatment in cases of T. cruzi infection using prevention and reversion schemes. In the Se prevention scheme, mice were given Se supplements (2 ppm) starting two weeks prior to inoculation with T. cruzi(Brazil strain) and continuing until 120 days post-infection (dpi). In the Se reversion scheme, mice were treated with Se (4 ppm) for 100 days, starting at 160 dpi. Dilatation of the right ventricle was observed in the infected control group at both phases of T. cruzi infection, but it was not observed in the infected group that received Se treatment. Surviving infected mice that were submitted to the Se reversion scheme presented normal P wave values and reduced inflammation of the pericardium. These data indicate that Se treatment prevents right ventricular chamber increase and thus can be proposed as an adjuvant therapy for cardiac alterations already established by T. cruzi infection.

A contemporary approach to a young female patient with Loeys-Dietz syndrome and an uncomplicated type B aortic dissection: a case report.

BACKGROUND: Aortic dissection is a relatively uncommon, but often catastrophic disease that requires early and accurate diagnosis. It often presents in patients with congenital connective tissue disorders. The current aortic surgical techniques are related with serious early and late complications. This case report emphasizes the importance of early diagnosis of aortic root dilatation and the risk of dissection, especially in patients with congenital connective tissue disorders. We present an alternative, contemporary and multidisciplinary approach based on the present state of knowledge. CASE PRESENTATION: We present a rare case of a young female patient with Loeys-Dietz syndrome who was admitted with an uncomplicated aortic dissection (Stanford type B / DeBakey type III) and a dilated aortic root. After a period of close surveillance and extensive vascular imaging, thoracic endovascular aortic repair was deemed to be technically not possible. Medical treatment was optimized and our patient successfully underwent a personalised external aortic root support procedure (PEARS) as a contemporary alternative to existing aortic root surgical techniques. CONCLUSIONS: This case highlights the importance of interdisciplinary approach, close follow-up and multimodality imaging. The decision to intervene in a chronic type B aortic dissection is still challenging and should be made in experienced centers by an interdisciplinary team. However, if an acute complication occurs, thoracic endovascular aortic repair TEVAR is the method of choice. In all cases optimal medical treatment is important. There is increasing evidence that personalized external aortic root support procedure PEARS is effective in stabilizing the aortic root and preventing its dilatation and dissection not only in patients with Marfan syndrome, but also in other cases of aortic root dilation of other etiologies. Moreover, many publications have reported the additional benefit of reduction or even eradication of aortic regurgitation by improving coaptation of the aortic valve leaflets in dilated aortas.

Meta-analysis Examining the Usefulness of Angiotensin Receptor blockers for the Prevention of Aortic Root Dilation in Patients With the Marfan Syndrome.

The Marfan syndrome (MFS) patients are highly predisposed to thoracic aortic aneurysm and/or dissection, with virtually every patient having evidence of aortic disease at some point during their lifetime. We conducted a meta-analysis to investigate the efficacy of angiotensin receptor blockers (ARBs) in slowing down the progression of aortic dilatation in MFS patients. PUBMED, EMBASE, and COCHRANE databases were searched for relevant articles published from inception to February 1, 2020. We included randomized clinical trials evaluating the effect of ARBs on aortic root size in patients with MFS with a follow-up period of at least 2.5 years. Seven studies were included with a total of 1,510 patients. Our analysis demonstrated a significantly smaller change in aortic root and ascending aorta dilation in the ARBs treated group when compared with placebo (mean difference 0.68; 95% confidence interval [CI] -1.31 to -0.04; p = 0.04, I2 = 94%, and mean difference -0.13, 95% CI -0.17 to -0.09; p < 0.00001, I2 = 0%, respectively). ARBs as an add-on therapy to beta-blockers resulted in a significantly smaller change in aortic root dilation when compared with the arm without ARBs (mean difference -2.06, 95% CI -2.54 to -1.58; p < 0.00001, I2 = 91%). However, there was no statistically significant difference in the number of clinical events (aortic complications/surgery) observed in the ARBs arm when compared with placebo (Risk ratio of 1.01, 95% CI 0.74 to 1.38; p = 0.94, I2 = 0%). In conclusion, ARBs therapy is associated with a slower progression of aortic root dilation when compared with placebo and as an addition to beta-blocker therapy.

Update on phototherapeutic keratectomy.

PURPOSE OF REVIEW: To review all recent publications on the use of phototherapeutic keratectomy (PTK). RECENT FINDINGS: Recent studies confirm the beneficial outcomes of PTK in a variety of anterior corneal disorder: anterior stromal scars, dystrophies of the corneal epithelium and the anterior stroma, and elevated corneal lesions. They also try to evaluate the biomechanical properties of eyes with granular corneal dystrophy undergoing PTK, in an effort to prevent iatrogenic ectasia. The different genotypes in patients with transforming growth factor, beta-induced linked corneal dystrophies have recently been correlated to the surgical outcome after PTK. An extensive review of recurrent corneal erosion syndrome identified PTK as the most effective treatment. In the developing world, the most common indication for PTK is still bullous keratopathy, as PTK can be successfully used while waiting for penetrating keratoplasty. SUMMARY: PTK can successfully treat a variety of conditions of the anterior cornea. New studies may further expand its use.