Extended and Safe Support with the CentriMag® Temporary Ventricular Assist Device Implanted with Skirted-Cannula Technique

Objectives

CentriMag® (Abbott, Pleasanton, CA, USA) is indicated for temporary circulatory support for up to 30 days. Extended support is not uncommon, and the results vary considerably. Herein, we review our experience on extended support.

Methods

We retrospectively analyzed 19 patients supported with CentriMag as a bridge to recovery, long-term ventricular assist device or transplantation from September 2011 to October 2021.

Results

Nineteen patients (16 men and 3 women; mean age 51.7 ± 9.2 years) had CentriMag left ventricular assist device (LVAD) implantation with the skirted-cannula technique. Twelve (63.2%), 6 (31.6%), and 1 (5.3%) patient were in INTERMACS 1, 2, and 3, respectively. The aims of support were bridge-to-decision in 3 patients (15.8%), and bridge-to-transplantation in 16 patients (84.2%). Fourteen patients were supported for longer than 30 days, while 5 patients had their CentriMag removed before 30 days. Of the 5 patients supported for less than 30 days, 3 died early after implantation due to complications of prolonged shock. The other 2 patients were successfully transplanted. Among the 14 patients supported for longer than 30 days, 1 patient died after transplantation and 13 patients survived either after transplantation or weaning off CentriMag. The overall 1-year survival rate was 73.7%. The duration of support for all patients ranged from 6 to 191 days (64 ± 61 days; median 41 days).

Conclusions

The skirted cannula technique for apical cannulation in implantation of CentriMag LVAD is an easy, safe and durable technique. Immediate post-operative and long-term complications are not common. Its use over 30 days is associated with acceptable survival.

Coronavirus disease 2019 and cardiovascular disease

Severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2), the virus behind the coronavirus disease 2019 (COVID-19) pandemic, is a type of RNA virus that is nonsegmented. Cardiovascular diseases (CVDs) increase the mortality risk of patients. In this review article, we overview the existing evidence regarding the potential mechanisms of myocardial damage in coronavirus disease 2019 (COVID-19) patients. Having a comprehensive knowledge of the cardiovascular damage caused by SARS-CoV-2 and its underlying mechanisms is essential for providing prompt and efficient treatment, ultimately leading to a reduction in mortality rates. Severe COVID-19 causes acute respiratory distress syndrome and shock in patients. In addition, awareness regarding COVID-19 cardiovascular manifestations has increased, including the adverse impact on prognosis with cardiovascular involvement. Angiotensin-converting enzyme 2 receptor may play a role in acute myocardial injury caused by SARS-CoV-2 infection. COVID-19 patients experiencing heart failure may have their condition exacerbated by various contributing factors and mechanisms. Increased oxygen demand, myocarditis, stress cardiomyopathy, elevated pulmonary pressures, and venous thrombosis are potential health issues. The combination of these factors may lead to COVID-19-related cardiogenic shock, resulting in acute systolic heart failure. Extracorporeal membrane oxygenation (ECMO) and left ventricular assist devices (LVADs) are treatment options when inotropic support fails for effective circulatory support. To ensure effective COVID-19-related cardiovascular disease (CVD) surveillance, it is crucial to closely monitor the future host adaptation, viral evolution, and transmissibility of SARS-CoV-2, given the virus's pandemic potential.

The potential of using itaconate as treatment for inflammation-related heart diseases

Intracellular metabolites can cause critical changes in biological functions. Itaconate is perhaps the most fascinating substance in macrophages. Lipopolysaccharide can activate aconitate decarboxylase 1 and induces the generation of itaconate from the tricarboxylic acid cycle by decarboxylation of cis-aconitate. It has been reported that itaconate has beneficial effects on inflammation and oxidation. The mechanisms involved in these effects include the suppression of succinate dehydrogenase, the activation of nuclear factor E2-related factor 2 by alkylation of Kelch-like ECH-associated protein 1, suppression of aerobic glycolysis through regulation of glyceraldehyde-3-phosphate dehydrogenase and fructose-bisphosphate aldolase A, and suppression of IκBζ translation through activating transcription factor 3 activation. All of these findings elucidated the possible therapeutic implications of itaconate in inflammation-related diseases. In this review, we highlight that itaconate is a crucial molecule of the immunomodulatory response in macrophages and can regulate between immune response and cardiovascular metabolism. Furthermore, these discoveries suggest that itaconate is a very novel therapeutic molecule for the treatment of inflammation-related heart diseases.

Influence of Resveratrol on the Cardiovascular Health Effects of Chronic Kidney Disease

Cardiovascular disease (CVD) is closely related to chronic kidney disease (CKD), and patients with CKD have a high risk of CVD-related mortality. Traditional CVD risk factors cannot account for the higher cardiovascular risk of patients with CKD, and standard CVD interventions cannot reduce the mortality rates among patients with CKD. Nontraditional factors related to mineral and vitamin-D metabolic disorders provide some explanation for the increased CVD risk. Non-dialyzable toxins, indoxyl sulfate (IS) and p-cresol sulfate (PCS)—produced in the liver by colonic microorganisms—cause kidney and vascular dysfunction. Plasma trimethylamine-N-oxide (TMAO)—a gut microbe-dependent metabolite of dietary L-carnitine and choline—is elevated in CKD and related to vascular disease, resulting in poorer long-term survival. Therefore, the modulation of colonic flora can improve prospects for patients with CKD. Managing metabolic syndrome, anemia, and abnormal mineral metabolism is recommended for the prevention of CVD in patients with CKD. Considering nontraditional risk factors, the use of resveratrol (RSV), a nutraceutical, can be helpful for patients with CVD and CKD. This paper discusses the beneficial effects of RSV on biologic, pathophysiological and clinical responses, including improvements in intestinal epithelial integrity, modulation of the intestinal microbiota and reduction in hepatic synthesis of IS, PCS and TMAO in patients with CVD and CKD.

Cardiac Myxoma With Unusual Obstructive and Embolic Presentations: Concurrent Stroke and Angiography-Negative Myocardial Infarction--A Case Report

We present a case of cardiac myxoma with atypical presentations of concurrent stroke and angiography-negative myocardial infarction. The case emphasizes the importance of basic echocardiography and timely surgery in the management of cardiac myxoma. An elderly woman presented to the emergency department in an unconscious state. Electrocardiogram and elevated cardiac enzymes suggested acute myocardial infarction; however, immediate coronary angiography proved patency. Basic echocardiography revealed an oscillating left atrial myxoma obstructing inflow through the mitral valve. After regaining consciousness while in the intensive care unit, the patient developed respiratory distress and shock, and emergent en bloc resection was performed. Ataxia was noted in her postoperative course and multiple small cerebellar infarcts were found on magnetic resonance imaging. After a 1-month period of rehabilitation, the patient recovered well and continues to be followed as an outpatient. Cardiac myxoma requires timely management and may be missed if not included in the differential diagnoses. Basic echocardiography, also called focused cardiac ultrasound, may aid in the diagnosing of perplexing cardiac cases.

Challenging carotid intervention after total arch rerouting and hybrid zone 0 elephant trunk repair for a complicated type A aortic dissection

PURPOSE

To report a challenging carotid intervention after total arch rerouting and hybrid zone 0 elephant trunk repair.

CASE REPORT

A 54-year-old man developed symptomatic left carotid artery restenosis 2 weeks after total arch rerouting and hybrid zone 0 elephant trunk repair for acute retrograde type A aortic dissection with left carotid malperfusion. Because the origins of the 3 supra-aortic branches were already transected and rerouted to the proximal end of the reconstructed ascending aortic graft, the peripheral access routes for carotid intervention were deemed difficult, with little chance of success due to acute angles between these rerouted supra-aortic branches and the ascending aortic graft. Emergent carotid artery stenting was therefore performed via sternal reentry with successful restoration of cerebral perfusion.

CONCLUSION

Total arch rerouting, facilitating hybrid endovascular repair for extensive thoracic aortic disease, creates an extremely deformed arch anatomy that renders subsequent carotid intervention a challenging task.

Ectopic and atretic ostium of left main coronary artery: from interleaflet triangle between left and noncoronary cusps

Left main coronary artery atresia is an extremely rare coronary anomaly in which there is no left coronary ostium and the left main trunk ends blindly. Ectopic origin of the left coronary artery from the left ventricle is an even rarer condition. Herein, we describe the case of a 37-year-old woman whose left main coronary artery atresia was not corrected during previous surgical correction of patent ductus arteriosus and aortic insufficiency. Five years after that first operation, the patient developed severe angina and heart failure. She underwent coronary artery bypass grafting with greater saphenous vein directly to the left main coronary artery trunk, along with associated procedures. The operative findings revealed an ectopic and atretic ostium of the left main coronary artery from the interleaflet triangle between the left and noncoronary cusps, which we believe is a specific congenital coronary anomaly.

Painless aortic dissection masquerading as brainstem stroke with catastrophic anticoagulant use

Painless aortic dissection with only focal neurological symptoms and signs can be a great challenge to the emergency physician. Inadvertently and erroneous treatment of stroke may threaten patient's life. We present a patient with painless aortic dissection (DeBakey I), which was initially misdiagnosed as brainstem stroke with catastrophic anticoagulant use. Finally, the patient died of multiorgan failure after surgical intervention.

The use of different implant modalities in the atrophied ridge

Many implant practitioners have been taught to use one implant system by a specific manufacturer. However, to successfully treat a patient, implant clinicians must learn to utilize the strengths of various systems when the patient's condition warrants it. The purpose of this paper is to illustrate how an edentulous patient with atrophied bone was treated with multiple-model implant procedures. Her treatment included different root form implants, bone spreading augmentations, endosseous submerged blades, tricortical support Diskimplants, and a custom-made ramus blade implant.

A new method for the preparation of polymeric porous layer open tubular columns for GC application

A new method to prepare polymeric PLOT columns by using in situ polymerization technology is described. The method involves a straightforward in situ polymerization of the monomer. The polymer produced is directly coated on the metal tubing. This eliminates many of the steps needed in conventional polymeric PLOT column preparation. Our method is easy to operate and produces very reproducible columns, as shown previously (T. C. Shen. J. Chromatogr. Sci. 30, 239, 1992). The effects of solvents, tubing pretreatments, initiators and reaction temperatures in the preparation of PLOT columns are studied. Several columns have been developed to separate (1) highly polar compounds, such as water and ammonia or water and HCN, and (2) hydrocarbons and inert gases. A recent improvement has allowed us to produce bonded polymeric PLOT columns. These were studied, and the results are included also.

Atomic-Scale Desorption Through Electronic and Vibrational Excitation Mechanisms

The scanning tunneling microscope has been used to desorb hydrogen from hydrogen-terminated silicon (100) surfaces. As a result of control of the dose of incident electrons, a countable number of desorption sites can be created and the yield and cross section are thereby obtained. Two distinct desorption mechanisms are observed: (i) direct electronic excitation of the Si-H bond by field-emitted electrons and (ii) an atomic resolution mechanism that involves multiple-vibrational excitation by tunneling electrons at low applied voltages. This vibrational heating effect offers significant potential for controlling surface reactions involving adsorbed individual atoms and molecules.

Transplanting teeth successfully: autografts and allografts that work

This article suggests tooth transplantation as an alternative to other restorative options. The 10-year success rates for autografts--teeth moved from one location to another in a patient's mouth--range from 60 percent to 95 percent. Allografts, teeth moved from one person to another, are less successful. The authors report on one case of each type of transplant.

Partial embolization of the spleen in patients with thalassemia

PURPOSE

The role of partial splenic embolization in alleviating hyperslenism was evaluated in children with thalassemia.

PATIENTS AND METHODS

Five children with thalassemia (three with alpha-thalassemia, two with beta-thalassemia) underwent embolization with polyvinyl alcohol particles. In two patients, a second splenic embolization was required.

RESULTS

Of the four patients who were transfusion dependent before embolization, two no longer needed transfusion after embolization and two had decreased requirements. In fifth patient who was not transfusion dependent, the hemoglobin level increased from 7.5 g/dL to 8.2 g/dL (75 to 82 g/L) after embolization. The mean platelet count also increased after embolization in all five patients from 266 x 10(9)/L to 480 x 10(9)/L, and the mean leukocyte count increased in four of the five patients from 7.29 x 10(9)/L to 10.1 x 10(9)/L. In the fifth patient, it was unchanged. In all five patients, there was a decrease in spleen size. All patients experienced abdominal pain, but no other severe complications were noted.

CONCLUSION

In these five patients, partial splenic embolization was a safe procedure that may be an acceptable alternative to partial or total surgical splenectomy. Transfusion requirements and the spleen size were reduced and the leukocyte and platelet counts increased.

In-situ polymerized PLOT columns III: divinylbenzene copolymers and dimethacrylate homopolymers

Studies of divinylbenzene copolymers and dimethacrylate homopolymers indicate that the polymer pore size controls the separation of water and ammonia on porous-layer-open-tubular (PLOT) columns. To a lesser degree, the polarity of the polymers also affects the separation of a water-ammonia gas mixture. Our results demonstrate that the pore size can be regulated by controlling the cross-linking density or the chain length between the cross-linking functional groups. An optimum pore size will provide the best separation of water and ammonia.

In-situ polymerization PLOT columns I: divinylbenzene

A novel method for preparation of porous-layer open-tubular (PLOT) columns is described. The method involves a simple and reproducible, straight-forward in-situ polymerization of monomer directly on the metal tube.

[A study of changes in the ratio of collagen types in skin after long-term treatment with topical glucocorticoids]

The topical glucocorticoids, widely used in the treatment of a variety of skin disorders, usually induce skin atrophy after long-term administration. In this study, the skin from a 30-year-old female patient was used, and the changes in the ratio of collagen types in atrophic skin derived from the treatment with glucocorticoid were investigated in comparison with that of normal human skin. By transmission electron microscopy, the collagen fibrils in the papillary dermis of normal skin were loose and fine, their diameters ranging from 30 to 40 nm; while those in the atrophic skin appeared tightly compact, their diameters increasing to 50-60 nm. The collagen chains, alpha 1 (I), alpha 2 and alpha 2 (III), from peptic digest of skin were separated by interrupted gel electrophoresis. The ratios of collagen type III to type I as calculated from the normal skins of a 21- and a 39-week fetus and a 36-year-old human were 49.45, 45.51 and 43.65%, respectively, while that of the atrophic skin was 12.89%. Therefore, the persistent treatment of skin with topical glucocorticoids results in a decrease in the ratio of collagen type III to type I.

Occurrence of nitrate reductase inhibitor in rice plants

Nitrate reductase inhibitor is usually found in the roots of rice plants (Oryza sativa L. cv MR7), but it was also produced in the shoots of aging plants. The inhibitor was inducible in the shoot of rice seedlings by dark, minus-nitrate or plus-ammonium treatments. There appears to be a general involvement of the inhibitor in the control of nitrate assimilation in the plant.

Effect of reduced pyridine nucleotides and tungstate on the in vitro insertion of molybdenum into demolybdo-nitrate reductase of Chlorella vulgaris

Demolybdo-nitrate reductase (cytochrome c reductase) (NADH: acceptor oxidoreductase, EC 1.6.99.3) of Chlorella vulgaris can be activated in vitro to nitrate reductase by insertion of Mo from molybdate into the apoprotein. Evidence is here presented that reduction of the enzyme by reduced pyridine nucleotides inhibits the process of molybdenum insertion. This report also describes the effect of molybdate and tungstate concentration on the activation process. The activation is sigmoidally related to molybdate concentration with a calculated Hill coefficient of NH = 3. At suboptimal molybdate concentrations, tungstate stimulates enzyme activation by molybdate; but at saturating molybdate concentrations, tungstate is inhibitory. These facts are regarded as an indication that molybdate and tungstate are both positive effectors of molybdenum incorporation, but that they are competitors for the active Mo center.

Molybdenum insertion in vitro in demolybdo nitrate reductase of Chlorella vulgaris

Demolybdo nitrate reductase (also called cyt c reductase) of Chlorella vulgaris has been converted to active nitrate reductase by insertion of Mo from Na2MoO4 in vitro. A procedure is described which consistently gives about 0.3 unit of nitrate reductase from about 6 units of cyt c reductase, a yield of 30% of the maximum expected, if we calculate on a basis of a ratio of 6 to 1 for the cyt c reductase/nitrate reductase of purified normal enzyme. The demolybdoenzyme is incubated for 30 s at 31 degrees C with molybdate and reduced glutathione (GSH) at pH 4.8, and the pH is then raised to 7, and the incubation continued for 20 min. At the acid pH, there must be a partial denaturation or unfolding which permits Mo insertion, with a refolding to active enzyme at the higher pH. The GSH is not essential for activation, but in its absence the yield of active enzyme was about 50% lower. Experiments with labeled GSH showed that no GSH was incorporated into the protein during the activation procedure. Although the enzyme activity measurements suggested that only 30% of the enzyme was activated, measurements with 99Mo showed that there was one Mo incorporated per subunit weight of 90,000. The Km for nitrate of the activated nitrate reductase was identical with the Km for nitrate of the normal enzyme. On gradient centrifugation, activated nitrate reductase, cyt c reductase, and normal nitrate reductase all behaved identically.

Nitrate reductase inhibitor of rice plants

Two fractions of nitrate reductase inhibitor activities were found in extracts of primary and regenerated roots of nitrate-grown rice seedlings. The inhibitor was proteinaceous in nature and specific to nitrate reductase. The main site of action of the inhibitor was the NADH: cytochrome c reductase component of nitrate reductase. NADH was able to protect the NADH:nitrate reductase against the inhibitor.

NADH- and NAD(P)H-Nitrate Reductases in Rice Seedlings

By use of affinity chromatography on blue dextran-Sepharose, two nitrate reductases from rice (Oryza sativa L.) seedlings, specifically, NADH:nitrate oxidoreductase (EC 1.6.6.1) and NAD(P)-H:nitrate oxidoreductase (EC 1.6.6.2), have been partially separated. Nitrate-induced seedlings contained more NADH-nitrate reductase than NAD(P)H-nitrate reductase, whereas chloramphenicol-induced seedlings contained primarily NAD(P)H-nitrate reductase. NAD(P)H-nitrate reductase was shown to utilize NADPH directly as reductant. This enzyme has a preference for NADPH, but reacts about half as well with NADH.

Nitrate reductase of rice seedlings and its induction by organic nitro-compounds

Nitrate simultaneously induced NADH- and NADPH-nitrate reductase activities in rice seedlings. Chloramphenicol, other organic nitro-compounds such as o-nitroaniline and 2,4-dinitrophenol and nitrite also induced nitrate reductase in rice seedlings. The nitrate- or nitrite-induced nitrate reductase could accept electrons more efficiently from NADH than NADPH. However, when this enzyme was induced by organic nitro-compounds, it could accept electrons more efficiently from NADPH than NADH.

Variation in the nitrate reductase of rice seedlings

Nitrate reductase was induced in rice seedlings by nitrate and by chloramphenicol. During the induction period the different enzyme activities associated with nitrate reductase increased to different degrees. Nitrate induced high NADH-nitrate reductase activity and a great increase in the NADH-cytochrome c reductase activity which was associated with the nitrate reductase in a sucrose gradient. Chloramphenicol induced a nitrate reductase which had higher activity with NADPH than NADH. Chloramphenicol also induced a marked increase in NADPH-cytochrome c reductase activity as well as in NADH-cytochrome c reductase activity. Both activities were associated with the nitrate reductase in a sucrose gradient.After partial purification by sucrose gradient sedimentation or by starch gel electrophoresis, the nitrate reductase of rice induced by nitrate and chloramphenicol showed the same preference in pyridine nucleotide cofactors as was shown by the crude enzyme extracts.

The induction of nitrate reductase and the preferential assimilation of ammonium in germinating rice seedlings

Nitrate reduotase is induced by nitrate in excised embryos and germinating intact seedlings of rice (Oryza sativa L.). The enzyme is induced 24 hr after imbibition. The rate of enzyme formation increases with the age of seedlings. There is a lag period of 30 to 40 min between the addition of substrate and the formation of nitrate reductase. Formation of the enzyme is promoted by the presence of ammonium. Chloramphenicol, actinomycin D and cycloheximide effectively inhibit the formation of nitrate reductase.Rice seedlings can assimilate nitrate from the beginning of germination. However, the utilization of nitrate is completely suppressed by the presence of ammonium. As soon as ammonium is depleted from the medium, nitrate utilization is resumed. Ammonium inhibits the first step of nitrate reduction, i.e., NO(-) (3) --> NO(-) (2), but does not inhibit the assimilation of nitrite. This provides an example of feedback inhibition in higher plants.