Update on diabetic cardiomyopathy: inches forward, miles to go.

Diabetes causes cardiomyopathy, both directly and by potentiating the effect of its common comorbidities, coronary artery disease and hypertension, on its development. With the common and growing prevalence of diabetes worldwide, diabetic cardiomyopathy is a significant public health problem. Recent research identifies both mitochondrial dysfunction and epigenetic effects as newly recognized factors in the complex pathogenesis of diabetic cardiomyopathy. Diagnostically, specialized echocardiography techniques, cardiac magnetic resonance imaging, and serologic biomarkers all appear to have promise in detecting the early stages of diabetic cardiomyopathy. Research into treatments includes both traditional diabetes and heart failure therapies, but also explores the potential of newer metabolic and anti-inflammatory agents. These recent insights provide important additions to our knowledge about diabetic cardiomyopathy, but much remains unknown.

Association between hyperglycemia at admission during hospitalization for acute myocardial infarction and subsequent diabetes: insights from the veterans administration cardiac care follow-up clinical study.

OBJECTIVE: Among patients with acute myocardial infarction (AMI) without known diabetes, hyperglycemia at admission is common and associated with worse outcomes. It may represent developing diabetes, but this association is unclear. Therefore, we examined the association between hyperglycemia (≥140 mg/dL) at admission and evidence of diabetes among patients with AMI without known diabetes within 6 months of their hospitalization. RESEARCH DESIGN AND METHODS: We studied a national cohort of consecutive patients with AMI without known diabetes presenting at 127 Veterans Affairs hospitals between October 2005 and March 2011. Evidence of diabetes either at discharge or in the following 6 months was ascertained using diagnostic codes, medication prescriptions, and/or elevated hemoglobin A1c. Association between hyperglycemia at admission and evidence of diabetes was evaluated using regression modeling. RESULTS: Among 10,499 patients with AMI without known diabetes, 98% were men and 1,761 (16.8%) had hyperglycemia at admission. Within 6 months following their index hospitalization, 208 patients (11.8%) with hyperglycemia at admission had evidence of diabetes compared with 443 patients (5.1%) without hyperglycemia at admission (P < 0.001). After multivariable adjustment, hyperglycemia at admission was significantly associated with subsequent diabetes odds ratio 2.56 (95% CI 2.15-3.06). Among those with new evidence of diabetes, 41% patients (267 of 651) had a hemoglobin A1c ≥6.5% without accompanying diagnostic codes or medication prescriptions, suggesting they had unrecognized diabetes. CONCLUSIONS: Hyperglycemia at admission occurred in one of six patients with AMI without known diabetes and was significantly associated with new evidence of diabetes in the 6 months following hospitalization. In addition, two of five patients with evidence of diabetes were potentially unrecognized. Accordingly, diabetes-screening programs for hyperglycemic patients with AMI may be an important component of optimal care.

Bedside ultrasound is a practical and reliable measurement tool for assessing quadriceps muscle layer thickness.

BACKGROUND: Critically ill patients commonly experience skeletal muscle wasting that may predict clinical outcome. Ultrasound is a noninvasive method that can measure muscle quadriceps muscle layer thickness (QMLT) and subsequently lean body mass (LBM) at the bedside. However, currently the reliability of these measurements are unknown. The objectives of this study were to evaluate the intra- and interreliability of measuring QMLT using bedside ultrasound. METHODS: Ultrasound measurements of QMLT were conducted at 7 centers on healthy volunteers. Trainers were instructed to perform measurements twice on each patient, and then a second trainee repeated the measurement. Intrarater reliability measured how consistently the same person measured the subject according to intraclass correlation (ICC). Interrater reliability measured how consistently trainer and trainee agreed when measuring the same subject according to the ICC. RESULTS: We collected 42 pairs of within operator measurements with an ICC of .98 and 78 pairs of trainer-to-trainee measurements with an ICC of .95. There were no statistically significant differences between the trainer and trainee results (trainer and trainee mean = -0.028 cm, 95% CI = -0.067 to -0.011, P = .1607). CONCLUSIONS: Excellent intra- and interrater reliability for ultrasound measurements of QMLT in healthy volunteers was observed when performed by a range of providers with no prior ultrasound experience, including dietitians, nurses, physicians, and research assistants. This technique shows promise as a method to evaluate LBM status in ICU or hospital settings and as a method to assess the effects of nutrition and exercise-based interventions on muscle wasting.

Cardiac crossroads: deciding between mechanical or bioprosthetic heart valve replacement.

Nearly 15 million people in the United States suffer from either aortic or mitral valvular disease. For patients with severe and symptomatic valvular heart disease, valve replacement surgery improves morbidity and mortality outcomes. In 2009, 90,000 valve replacement surgeries were performed in the United States. This review evaluates the advantages and disadvantages of mechanical and bioprosthetic prosthetic heart valves as well as the factors for consideration in deciding the appropriate valve type for an individual patient. Although many caveats exist, the general recommendation is for patients younger than 60 to 65 years to receive mechanical valves due to the valve's longer durability and for patients older than 60 to 65 years to receive a bioprosthetic valve to avoid complications with anticoagulants. Situations that warrant special consideration include patient co-morbidities, the need for anticoagulation, and the potential for pregnancy. Once these characteristics have been considered, patients' values, anxieties, and expectations for their lifestyle and quality of life should be incorporated into final valve selection. Decision aids can be useful in integrating preferences in the valve decision. Finally, future directions in valve technology, anticoagulation, and medical decision-making are discussed.

Blood pressure trajectories and associations with treatment intensification, medication adherence, and outcomes among newly diagnosed coronary artery disease patients.

BACKGROUND: Blood pressure (BP) control among coronary artery disease patients remains suboptimal in clinical practice, potentially due to gaps in treatment intensification and medication adherence. However, longitudinal studies evaluating these relationships and outcomes are limited. METHODS AND RESULTS: We assessed BP trajectories among health maintenance organization patients with hypertension and incident coronary artery disease. BP trajectories were modeled over the year after coronary artery disease diagnosis, stratified by target BP goal. Treatment intensification (increase in BP therapies in the setting of an elevated BP), medication adherence (percentage of days covered with BP therapies), and outcomes (all-cause mortality, myocardial infarction, and revascularization) were evaluated in multivariable models: 9569 patients had a <140/90 mm Hg BP target and 12,861 had a <130/80 mm Hg BP target. Within each group, 4 trajectories were identified: good, borderline, improved, and poor control. After adjustment, increasing BP treatment intensity was significantly associated with better BP trajectories in both groups. Medication adherence had inconsistent effects. There were no significant differences in combined outcomes by BP trajectory, but among the diabetes and renal disease cohort, borderline control patients were less likely to have myocardial infarction (odds ratio, 0.61; 95% confidence interval, 0.40-0.93), and good control patients were less likely to have myocardial infarction (odds ratio, 0.53; 95% confidence interval, 0.34-0.84) or a revascularization procedure (odds ratio, 0.66; 95% confidence interval, 0.47-0.93) compared with poor control patients. CONCLUSIONS: In this health maintenance organization population, treatment intensification but not medication adherence significantly affects BP trajectories in the year after coronary artery disease diagnosis. Better BP trajectories are associated with lower rates of myocardial infarction and revascularization.