Dr Rodney Franklin is the focus of our third in a planned series of interviews in Cardiology in the Young entitled, “Global Leadership in Paediatric and Congenital Cardiac Care.” Dr Franklin was born in London, England, spending the early part of his childhood in the United States of America before coming back to England. He then attended University College London Medical School and University College Hospital in London, England, graduating in 1979. Dr Franklin would then go on to complete his general and neonatal paediatrics training in 1983 at Northwick Park Hospital and University College Hospital in London, England, followed by completing his paediatric cardiology training in 1989 at Great Ormond Street Hospital for Children in London, England. During this training, he additionally would hold the position of British Heart Foundation Junior Research Fellow from 1987 to 1989. Dr Franklin would then complete his training in 1990 as a Senior Registrar and subsequent Consultant in Paediatric and Fetal Cardiology at Wilhelmina Sick Children’s Hospital in Utrecht, the Netherlands. He subsequently obtained his research doctorate at University of London in 1997, consisting of a retrospective audit of 428 infants with functionally univentricular hearts.

Dr Franklin has spent his entire career as a Consultant Paediatric Cardiologist at the Royal Brompton & Harefield Hospital NHS Foundation Trust, being appointed in 1991. He additionally holds honorary Consultant Paediatric Cardiology positions at Hillingdon Hospital, Northwick Park Hospital, and Lister Hospital in the United Kingdom, and Honorary Senior Lecturer at Imperial College, London. He has been the Clinical Lead of the National Congenital Heart Disease Audit (2013–2020), which promotes data collection within specialist paediatric centres. Dr Franklin has been a leading figure in the efforts towards creating international, pan European, and national coding systems within the multidisciplinary field of congenital cardiac care. These initiatives include but are not limited to the development and maintenance of The International Paediatric & Congenital Cardiac Code and the related International Classification of Diseases 11th Revision for CHD and related acquired terms and definitions. This article presents our interview with Dr Franklin, an interview that covers his experience in developing these important coding systems and consensus nomenclature to both improve communication and the outcomes of patients. We additionally discuss his experience in the development and implementation of strategies to assess the quality of paediatric and congenital cardiac care and publicly report outcomes.

There has been a progressive evolution in systems of classification for cardiomyopathy, driven by advances in imaging modalities, disease recognition, and genetics, following initial clinical descriptions in the 1960s. A pathophysiological classification emerged and was endorsed by World Health Organisation Task Forces in 1980 and 1995: dilated, hypertrophic, restrictive, and arrhythmogenic right ventricular cardiomyopathies; subdivided into idiopathic and disease-specific cardiomyopathies. Genetic advances have increasingly linked “idiopathic” phenotypes to specific mutations, although most linkages exhibit highly variable or little genotype–phenotype correlation, confounded by age-dependent changes and varying penetrance. The following two dominant classification systems are currently in use, with advocates in both continents. First, American Heart Association (2006): “A heterogeneous group of diseases of the myocardium associated with mechanical and/or electrical dysfunction that usually exhibit inappropriate ventricular hypertrophy or dilatation due to a variety of causes that frequently are genetic”. These are subdivided to those predominantly involving the heart – primary – due to genetic mutation, including ion channelopathies, acquired disease, or mixed; and those with systemic involvement in other organ systems – secondary. Second, European Society of Cardiology (2008): “A myocardial disorder in which heart muscle is structurally and functionally abnormal… sufficient to cause the observed myocardial abnormality”, with subdivision to familial and non-familial, excluding ion channelopathies, and split to specific disease subtypes and idiopathic. Further differences exist in the definitions for hypertrophic cardiomyopathy; however, whichever high-level classification is used, the clinical reality remains phenotype driven. Clinical evaluation and diagnostic imaging dominate initial patient contact, revealing diagnostic red flags that determine further specific tests. Genetic testing is undertaken early. A recent attempt to harmonise these competing systems named the MOGE(S) system, based on descriptive logical nosology, currently remains unproven as a fully practical solution.

The max-plus algebra is well known and has useful applications in the investigation of discrete event systems and affine equations. Structural matrix rings have been considered by many authors too. This article introduces more general structural matrix semirings, which include all matrix semirings over the max-plus algebra. We investigate properties of ideals in this construction motivated by applications to the design of centroid-based classification systems, or classifiers, as well as multiple classifiers combining several initial classifiers. The first main theorem of this paper shows that structural matrix semirings possess convenient visible generating sets for ideals. Our second main theorem uses two special sets to determine the weights of all ideals and describe all matrix ideals with the largest possible weight, which are optimal for the design of classification systems.