Congenital Absence of Pericardium: A Case Report and Technical Considerations in Cardiac Surgery

This case report describes a rare instance of left-sided congenital pericardial agenesis (CPA) encountered during coronary artery bypass grafting (CABG) in a 77-year-old male. In this unique case, the presence of an unusual strip of left pericardium containing the phrenic nerve posed significant surgical challenges. Special attention was required for the graft lay, ensuring adequate filling of the heart during assessment before closure, as well as emphasis on the need for generous graft length. Additionally, the evaluation of graft positioning prior to cardiopulmonary bypass was crucial. Despite these complexities, CABG was successfully performed with no complications to note. This case underscores the importance of adaptability in surgical technique to manage the unique challenges posed by CPA, leading to a positive outcome despite the atypical cardiac anatomy.

The impact of antiarrhythmics on human pulmonary arteries: Ex vivo characterization

Background and Aim

The safety and efficacy of the antiarrhythmic agents, amiodarone, and digoxin, in patients with pulmonary hypertension (PH), is not described well in the literature, although their use is common practice. Our study aims to investigate the effect of these drugs on pulmonary arteries (PA) which may have implications for their use in patients with PH.

Methods

Human PAs were obtained from consenting patients undergoing lobectomies. Arterials rings (n=40 from ten patients) were dissected form the tissue and mounted onto a multiwire myograph. The rings were preconstricted using prostaglandin F2α before the addition of additive dilutions of amiodarone and digoxin. Finally, the reagents were washed out and the arterial rings' viability was confirmed using acetylcholine and potassium chloride.

Results

Amiodarone had a slightly vasodilatory effect on the arterial rings, whereas digoxin had a relatively neutral effect. Amiodarone caused the greatest vasodilatory response at 100 µM with an active tension of -0.494 gram force with an EC50 of 9.42 µM. Digoxin produced no significant vasodilatory or vasoconstrictive response.

Conclusions

This study demonstrated the ex vivo effects of amiodarone and digoxin on human pulmonary arterial tension. The results of the study showed that neither amiodarone nor digoxin had any vasoconstrictive effects. Amiodarone also exhibited vasodilatory properties and, therefore, may be used preferentially as it could help reduce the impact of PH. However, more studies need to be conducted before we can confirm the safety of these drugs.

Relevance for Patients

The ambivalence surrounding treatment of postoperative arrhythmias in patients with PH results is a significant disparity between individual cases. Our study takes the first step in elucidating, in which drugs may be a safer treatment for patients with the aim to resolve the doubts clinicians may have about using these treatments. The principal goal of our work is to ensure that we are providing patients with the most effective and, more importantly, safest treatment.

Is ultra wide-field retinal imaging alone appropriate for retinal angioma screening in lower risk subjects attending Von Hippel-Lindau (VHL) clinics?

Purpose: To determine if non-mydriatic ultra wide-angle digital retinal imaging alone is effective for screening subjects considered to be at 50% or lower risk for developing retinal angiomas.Methods: Digital records and retinal images of subjects attending a regional Von-Hippel-Lindau disease multi-disciplinary clinic over a 12 month period were reviewed. Individuals were stratified for risk of developing retinal angiomas on the basis of age, clinical features and genetic risk. The image quality and necessity for subsequent mydriatic fundoscopy were assessed.Results: Eighty subjects from 55 pedigrees attended the VHL clinic over 12 months. Of these, 44 (55%) were considered to be at lower risk for retinal angiomatosis: 34 (77%) because they had reached at least 30 years of age without developing an angioma, 16 with a presenting solitary tumour of the type associated with VHL but no identifiable gene mutation, and 12 with a family history giving them a 50% risk of carrying a gene mutation. Eighteen patients fulfilled two low risk criteria. All were able to comply with imaging but poor image quality (limited view of the inferior retinal far-periphery) required subsequent dilated fundoscopy in five (6%) eyes of three patients.Conclusions: Non-mydriatic ultra wide-field retinal imaging enabled satisfactory assessment in over 95% of lower-risk VHL subjects. Virtual clinics or remote imaging of lower-risk subjects may improve both the efficiency and flexibility in the provision of multi-disciplinary VHL services and the patient experience.

From cholera to burns: a role for oral rehydration therapy

According to the practice guidelines of the American Bum Association on burn shock resuscitation, intravenous (i.v.) fluid therapy is the standard of care for the replacement of fluid and electrolyte losses in burn injury of > or = 20% of the total body surface area. However, in mass burn casualties, i.v. fluid resuscitation may be delayed or unavailable. Oral rehydration therapy (ORT), which has been shown to be highly effective in the treatment of dehydration in epidemics of cholera, could be an alternate way to replace fluid losses in burns. A prospective case series of three patients was carried out as an initial step to establish whether oral Ceralyte 90 could replace fluid losses requiring i.v. fluid therapy in thermal injury. The requirement of the continuing i.v. fluid therapy was reduced by an average of 58% in the first 24 hours after the injury (range 37-78%). ORT may be a feasible alternative to i.v. fluid therapy in the resuscitation of burns. It could also potentially save many lives in mass casualty situations or in resource-poor settings where i.v. fluid therapy is not immediately available. Further studies are needed to assess the efficacy of this treatment and to determine whether the present formulations of ORT for cholera need modification.