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Background: Endothelial injury occurring during cardiopulmonary bypass is a major contributing factor in the development of organ dysfunction, which leads to many of the postoperative complications occurring during cardiac surgery. Objective: This narrative review aims to summarize the main mechanisms of cardiopulmonary bypass - related disease, evaluating the unfavorable events leading to tissue injury, with a description of current pharmacologic and non-pharmacologic mechanisms to reduce CPB-related injury. Methods: A Medline/Pubmed/Scopus search was conducted using clinical queries with the key terms "cardiac surgery", “cardiopulmonary bypass”, "inflammation" and “endothelial injury”, and related MeSH terms, until July 2019. The search strategy included meta-analyses, randomized controlled trials, clinical trials, reviews and pertinent references. Patents were searched using the same key terms from https://patents.google.com/, www.uspto.gov, and www.freepatentsonline.com. Results: In this review, we discuss the current knowledge of the mechanisms of vascular endothelial cell injury, the acute inflammatory response, and the regulatory factors that control the extent of vascular injury during extracorporeal circulation, summarizing the main target of anti-inflammatory pharmacologic and non-pharmacologic strategies. Conclusion: Inflammatory response and endothelial dysfunction following cardiopulmonary bypass are the prices to pay for the benefits offered during cardiac surgery procedures. Counteracting the detrimental effect of extracorporeal circulation appears to be crucial to improve clinical outcomes in pediatric and adult cardiac surgery. The intrinsic complexity and the tight interplay of the factors involved might require a holistic approach against inflammation and endothelial response.

Diabetes is a major risk factor for cardiovascular disease, and recent advances in research indicate that a detailed understanding of the pathophysiology of its effects is mandatory to reduce diabetes-related mortality and morbidity. Advanced Glycation End Products (AGEs) play a central role in the genesis and progression of complications of both type 1 and type 2 diabetes mellitus, and have been found to be important even in non-diabetic patients as a marker of cardiovascular disease. AGEs have a profound impact on patient's prognosis regardless of the glycemic control, and therefore pharmacologic approaches against AGEs accumulation have been proposed over the years to treat cardiovascular diseases, parallel to a more detailed understanding of AGEs pathophysiology. Compounds with anti-AGEs effects are currently under investigation in both pre-clinical and clinical scenarios, and many of the drugs previously used to treat specific diseases have been found to have AGE-inhibitory effects. Some products are still in “bench evaluation”, whereas others have been already investigated in clinical trials with conflicting evidences. This review aims at summarizing the mechanisms of AGEs formation and accumulation, and the most relevant issues in pre-clinical and clinical experiences in anti-AGEs treatment in cardiovascular research.

Electrostimulation represents a well-known trophic factor for different tissues. In vitro electrostimulation of non-stem and stem cells induces myogenic predifferentiation and may be a powerful tool to generate cells with the capacity to respond to local areas of injury. We evaluated the effects of in vivo electrostimulation on infarcted myocardium using a miniaturized multiparameter implantable stimulator in rats. Parameters of electrostimulation were organized to avoid a direct driving or pacing of native heart rhythm. Electrical stimuli were delivered for 14 days across the scar site. In situ electrostimulation used as a cell-free, cytokine-free stimulation system, improved myocardial function, and increased angiogenesis through endothelial progenitor cell migration and production of vascular endothelial growth factor (VEGF). In situ electrostimulation represents a novel means to stimulate repair of the heart and other organs, as well as to precondition tissues for treatment with cell-based therapies.

Secondary alcohol metabolites and reactive oxygen species mediate cardiomyopathy induced by cumulative doses of antitumor anthracyclines, such as doxorubicin and epirubicin. Epirubicin exhibits a defective conversion to both toxic species, thereby inducing cardiotoxicity at doses higher than equiactive to doxorubicin; however, the gain in cardiac tolerability seems to be marginal compared with the magnitude of the metabolic defects of epirubicin. Cardiomyopathy may occur independent of toxic metabolites if a given anthracycline tends to accumulate in the heart; therefore, we characterized whether epirubicin showed an unusual accumulation in human myocardial strips incubated in plasma. Epirubicin exhibited a higher uptake and reached myocardial levels 2 times higher than those of doxorubicin. Epirubicin also showed a unique metabolization to doxorubicinolone, the product of epirubicin deglycosidation and carbonyl reduction. In diffusing from the strips to plasma, doxorubicinolone caused membrane permeation effects that augmented epirubicin elimination. Experiments with purified doxorubicinolone showed that the efflux of 1 mol doxorubicinolone promoted the concomitant elimination of as many as approximately 40 mol epirubicin. Doxorubicinolone could also diffuse from plasma back to the strips, causing a permeation effect that promoted epirubicin reuptake; however, this reverse process was slower and less potent. On balance, doxorubicinolone efflux diminished the epirubicin to doxorubicin accumulation ratio to approximately 1.5. These results suggest that the cardiac tolerability of epirubicin is limited by its accumulation in the heart and that such accumulation would be even higher in the absence of doxorubicinolone formation and efflux. These results may also serve guidelines for developing noncardiotoxic anthracyclines.