Research Spotlight

Packer, M. (2017). “Will long-acting glucagon-like peptide-1 analogues recapitulate our agonizing experience with cyclic amp-dependent positive inotropic agents in heart failure?” Eur J Heart Fail: 2017 Oct [Epub ahead of print].

Full text of this article.

Over the past three decades, substantial changes have taken place regarding our understanding of the role of cyclic AMP. It is now understood that cyclic AMP may be compartmented and that changes in subcellular pools may not have implications for cardiac contractility or cardiotoxicity.3 Treatments that increase cyclic AMP in the heart have been reported to have favourable effects on myocardial viability and angiogenesis as well as on cardiac remodelling.4,5 Phosphodiesterase inhibitors (i.e. cilostazol) have been developed for the treatment of patients with claudication, even though peripheral vascular disease and heart failure frequently coexist.

Michel, P., A. Menter and J. Griffin (2017). “A congenital naevus in a blaschkoid distribution.” Clin Exp Dermatol: 2017 Oct [Epub ahead of print].

Full text of this article.

NC is a rare hamartomatous proliferation of the pilo-sebaceous unit, usually evident at birth or appearingin early childhood. Most NCs arise sporadically, with afew adult onset cases reported secondary to trauma orirritation.1Men and women are equally affected, andthere is no evidence of racial aggregation. Rare associ-ations with cataracts, skeletal defects or central ner-vous system abnormalities characterize NC syndrome.

Linsk, A. M., K. R. Monden, G. Sankaranarayanan, W. Ahn, D. B. Jones, S. De, S. D. Schwaitzberg and C. G. L. Cao (2017). “Validation of the vblast pattern cutting task: A learning curve study.” Surg Endosc: 2017 Oct [Epub ahead of print].

Full text of this article.

BACKGROUND: Mastery of laparoscopic skills is essential in surgical practice and requires considerable time and effort to achieve. The Virtual Basic Laparoscopic Skill Trainer (VBLaST-PC(c)) is a virtual simulator that was developed as a computerized version of the pattern cutting (PC) task in the Fundamentals of Laparoscopic Surgery (FLS) system. To establish convergent validity for the VBLaST-PC(c), we assessed trainees’ learning curves using the cumulative summation (CUSUM) method and compared them with those on the FLS. METHODS: Twenty-four medical students were randomly assigned to an FLS training group, a VBLaST training group, or a control group. Fifteen training sessions, 30 min in duration per session per day, were conducted over 3 weeks. All subjects completed pretest, posttest, and retention test (2 weeks after posttest) on both the FLS and VBLaST(c) simulators. Performance data, including time, error, FLS score, learning rate, learning plateau, and CUSUM score, were analyzed. RESULTS: The learning curve for all trained subjects demonstrated increasing performance and a performance plateau. CUSUM analyses showed that five of the seven subjects reached the intermediate proficiency level but none reached the expert proficiency level after 150 practice trials. Performance was significantly improved after simulation training, but only in the assigned simulator. No significant decay of skills after 2 weeks of disuse was observed. Control subjects did not show any learning on the FLS simulator, but improved continually in the VBLaST simulator. CONCLUSIONS: Although VBLaST(c)- and FLS-trained subjects demonstrated similar learning rates and plateaus, the majority of subjects required more than 150 trials to achieve proficiency. Trained subjects demonstrated improved performance in only the assigned simulator, indicating specificity of training. The virtual simulator may provide better opportunities for learning, especially with limited training exposure.

Kovesdy, C. P., L. J. Appel, M. E. Grams, L. Gutekunst, P. A. McCullough, B. F. Palmer, B. Pitt, D. A. Sica and R. R. Townsend (2017). “Potassium homeostasis in health and disease: A scientific workshop cosponsored by the national kidney foundation and the american society of hypertension.” J Am Soc Hypertens: 2017 Oct [Epub ahead of print].

Full text of this article.

While much emphasis, and some controversy, centers on recommendations for sodium intake, there has been considerably less interest in recommendations for dietary potassium intake, in both the general population and patients with medical conditions, particularly acute and chronic kidney disease. Physiology literature and cohort studies have noted that the relative balance in sodium and potassium intakes is an important determinant of many of the sodium-related outcomes. A noteworthy characteristic of potassium in clinical medicine is the extreme concern shared by many practitioners when confronted by a patient with hyperkalemia. Fear of this often asymptomatic finding limits enthusiasm for recommending potassium intake and often limits the use of renin-angiotensin-aldosterone system blockers in patients with heart failure and chronic kidney diseases. New agents for managing hyperkalemia may alter the long-term management of heart failure and the hypertension, proteinuria, and further function loss in chronic kidney diseases. In this jointly sponsored effort between the American Society of Hypertension and the National Kidney Foundation, 3 panels of researchers and practitioners from various disciplines discussed and summarized current understanding of the role of potassium in health and disease, focusing on cardiovascular, nutritional, and kidney considerations associated with both hypo- and hyperkalemia.

Packer, M. (2017). “Why is the use of digitalis withering? Another reason that we need medical heart failure specialists.” Eur J Heart Fail: 2017 Oct [Epub ahead of print].

Full text of this article.

Contrary to popular opinion, William Withering did not discover digitalis nor was he the first to describe its use for heart failure. In 1785, the esteemed English botanist and physician wrote a pamphlet that summarized his experiences in 163 patients with dropsy. Yet, at the time, digitalis had been known to exert important pharmacological effects for 2000 years. In the first century, the Greek physician, Pedanius Dioscorides, noted the use of digitalis as a therapeutic agent; its application to heart failure was first recorded in print by Leonard Fuchs in 1542.1 Nevertheless, Withering was the first to systematically carry out clinical studies with the plant in a scientific manner, eliminating the superstition that had long surrounded it. Withering’s work was ground-breaking, not because of what he discovered, but how he approached its evaluation. It was the first use of the scientific method for the characterization of a pharmaceutical.