Role of ascorbic acid in cardiac allograft vasculopathy.

PURPOSE OF THE REVIEW: Cardiac allograft vasculopathy (CAV) is a progressive fibroproliferative disease which occurs after heart transplantation and is associated with significant long-term morbidity and mortality. Currently available strategies including statins, mammalian target of rapamycin (mTOR) inhibitors, and revascularization, have limited overall effectiveness in treating this pathology once the disease process is established. mTOR inhibitors, while effective when used early in the disease process, are not well tolerated, and hence not routinely used in post-transplant care. RECENT DATA: Recent work on rodent models have given us a novel mechanistic understanding of effects of ascorbic acid in preventing CAV. TET methyl cytosine dioxygenase2 (TET2) reduces vascular smooth muscle cell (VSMC) apoptosis and intimal thickening. TET2 is repressed by interferon γ (IFNγ) in the setting of CAV. Ascorbic acid has been shown to promote TET2 activity and attenuate allograft vasculopathy in animal models and CAV progression in a small clinical trial. SUMMARY: CAV remains a challenging disease process and needs better preventative strategies. Ascorbic acid improves endothelial dysfunction, reduces reactive oxygen species, and prevents development of intimal hyperplasia by preventing smooth muscle cell apoptosis and hyperproliferation. Further large-scale randomized control studies of ascorbic acid are needed to establish the role in routine post-transplant management.

Cardiac Metastatic Melanoma Causing Ventricular Arrhythmias Through Impaired Coronary Artery Vasodilation.

Melanoma is an aggressive malignant disease with a high rate of cardiac metastasis. There is a reported association between myocardial tumor invasion and ventricular arrhythmias. We present a case of cardiac metastatic melanoma causing ventricular arrhythmias through a novel mechanism of encasement of coronary arteries leading to reduced myocardial perfusion. (Level of Difficulty: Intermediate.).

An unusual presentation of invasive squamous cell carcinoma of the upper extremities in a patient with a history of severe electrical burns and chronic thermal and chemical exposure.

This is a case report that depicts an atypical presentation of very aggressive, metachronous invasive squamous cell carcinomas of the upper extremities in a patient with no prior history of precancerous or cancerous skin lesions and no significant solar radiation exposure. Potentially causative factors that played a role in the emergence of this aggressive form of skin cancer in this case study are multifactorial: (1) chronic thermal exposure of 3000 degrees F daily to his hands for an eight to ten-year time period; (2) chronic chemical exposure of DMSO solvent and higher levels of chemical contaminants such and finally; (3) a form of chronic immunosuppression as a result of his severe electrical burns that resulted in widespread second and third burns throughout his body.