QRS Fragmentation and the Risk of Sudden Cardiac Death in MADIT II

QRS Fragmentation and the Risk of Sudden Cardiac Death in MADIT II. Background: QRS fragmentation (fQRS) has been reported as a useful ECG parameter in predicting mortality in high‐risk postinfarction patients. Its prognostic value for sudden cardiac death (SCD) and ventricular arrhythmias in ischemic cardiomyopathy (ICM) remains unknown. Methods: MADIT II enrollment 12‐lead ECGs were analyzed for fQRS defined as RSR’ patterns (≥1 R’ or notching of S or R wave) in patients with a normal QRS duration and >2 notches on the R or S wave in patients with abnormal QRS duration, present in 2 contiguous leads. Exclusion criteria included a paced rhythm and an uninterpretable or incomplete ECG. Study endpoints included SCD, SCD or appropriate implantable cardioverter defibrillator (ICD) shock, and total mortality (TM). Results: Of the 1,232 ECGs reviewed, 1,040 were of suitable quality for fQRS analysis. QRS fragmentation was found in 33% of patients in any leads, in 10% of patients in anterior leads, in 8% of patients in lateral leads and in 21% of patients in inferior leads. Anterior and lateral location of QRS fragmentation was not associated with follow‐up events. Inferior location of fQRS was found to be predictive of SCD/ICD shock (hazard ratio [HR] 1.46, P = 0.032), SCD (HR 2.05, P = 0.007), and TM (HR 1.44, P = 0.036). This association was driven primarily by the increase in events found in LBBB patients: SCD/ICD shock (HR 2.05, P = 0.046), SCD (HR 4.24, P = 0.002), and TM (HR 2.82, P = 0.001). Conclusions: Fragmented QRS, especially identified in inferior leads, is predictive of SCD, SCD or appropriate ICD shock, and all‐cause mortality in patients with ICM. Identifying inferior fQRS in patients with LBBB is of particular prognostic significance and should reinforce the use of ICD therapy in this high‐risk group. (J Cardiovasc Electrophysiol, Vol. 23, pp. 1343‐1348, December 2012)     

PLASMA ACTH AND CORTISOL PROFILES IN ADDISONIAN PATIENTS RECEIVING CONVENTIONAL SUBSTITUTION THERAPY

Plasma ACTH and cortisol profiles were studied over 24 h in five Addisonian patients maintained in good health by conventional gluco- and mineralocorticoid treatment. Patients received their usual treatment (15--30 mg cortisol daily) in divided doses at 08.00 and 16.00 hours. Plasma cortisol concentrations differed from those of control subjects in being higher from 08.00 hours-noon and 17.00-18.00 hours and were unmeasurable (less than 20 nmol/l) during the period of active cortisol secretion (03.00-08.00 hours) observed in normal subjects. Peak plasma ACTH levels (618- greater than 1600 ng/l) occurred at 08.00-09.00 hours in the Addisonian patients and were much greater than those seen in control subjects (60-220 ng/l). Despite this, plasma ACTH fell promptly within 3 h of the morning dose to less than 100 ng/l and levels were indistinguishable from those seen in normal subjects over the period 12.00-02.00 hours. These results show that there are substantial differences between treated Addisonian and control subjects in respect of plasma cortisol and ACTH concentrations. The findings may lead to a better understanding of ACTH-cortisol relationships in disease states, including congenital adrenal hyperplasia where control of excessive ACTH secretion is clinically desirable.     

Critical review of nutrition assessment tools to measure malnutrition in chronic kidney disease

The use of the Subjective Global Assessment (SGA) and similar clinical tools for nutrition assessment is integral in the nutritional management of chronic kidney disease (CKD) patients. The present paper is a critical review of the quality of studies introducing and validating SGA‐based tools in CKD. In the CKD literature, clinical, predictive and criterion validity were investigated by a number of studies. Common limitations identified include the use of questionable statistical methods, difference in prevalence of malnutrition based on tool or administrator (i.e. dietitan, nephrologist or nurse) and use of inadequate reference tests to establish true nutrition status. The SGA appears to have the best diagnostic evidence to adequately detect the presence of abnormal nutrition status and prognostic evidence to predict poor outcome. Modified scored versions may improve clinician’s ability to detect degree of malnutrition; however, the present review indicates more work is required. Tools based on the original SGA claiming validity in CKD and potentially other clinical areas should be approached with caution. Critical evaluation of study design, reference tests and statistical methods is recommended before implementing new tools in practice.