Acute coronary syndromes (ACS) continue to be the most common morbid condition of industrialized nations. The advent of and technical improvements in revascularization and medical therapy have led to a steady decline in mortality rates. However, many patients who suffer unstable angina or myocardial infarction require further testing and risk stratification to guide therapeutic selection and prognosis assignment. Myocardial edema imaging with cardiac magnetic resonance (CMR) affords the ability to define the amount of myocardium at risk, refine estimates of prognosis and provide guidance for therapies with excellent sensitivity compared to standard clinical markers. This review will discuss the rationale for edema imaging, how it is performed using CMR and its potential clinical applications.
FRANK LEHMANN-HORN, MARC-ANDRÉ WEBER,1 ARMIN M. NAGEL,2 HANS-MICHAEL MEINCK,3 SIMON BREITENBACH, JOHANNES SCHARRER, and KARIN JURKAT-ROTT
Recently we reported a cytoplasmic sodium overload to cause a severe osmotic oedema in Duchenne muscular dystrophy (DMD). Our results suggested that this dual overload of sodium ions and water precedes the dystrophic process and persists until fatty muscle degeneration is complete. The present paper addresses the questions as to whether these overloads are important for the pathogenesis of the disease, and if so, whether they can be treated. As a first step, we investigated the effects of various diuretic drugs on a cell model of DMD, i.e. rat diaphragm strips previously exposed to amphotericin B. We found that both carbonic anhydrase inhibitors and aldosterone antagonists were able to repolarise depolarised muscle fibres. Since carbonic anhydrase inhibitors are known to have acidifying effects and this might be detrimental to the ventilation of DMD patients, we mainly concentrated on the modern spironolactone derivative, eplerenone. This drug had a very high repolarizing power, the parameter considered by us as being most relevant for a beneficial effect. In a pilot study we administered this drug to a 22-yr-old female DMD patient who was bound to an electric wheelchair and has had no corticosteroid therapy before. Eplerenone decreased both cytoplasmic sodium and water overload and increased muscle strength and mobility. We conclude that eplerenone has beneficial effects on DMD muscle. In our opinion the cytoplasmic oedema is cytotoxic and should be treated before fatty degeneration takes place.
Darach O h-Ici,1 John P Ridgway,2 Titus Kuehne,1 Felix Berger,1 Sven Plein,3 Mohan Sivananthan,4 and Daniel R Messroghli1