Comprehensive nutrient consumption estimation and metabolic profiling during ketogenic diet and relationship with myocardial glucose uptake on FDG-PET.

AIMS: The ketogenic diet (KD) is standard-of-care to achieve myocardial glucose suppression (MGS) for assessing inflammation using fluorine-18 fluorodeoxyglucose-positron emission tomography (FDG-PET). As KD protocols remain highly variable between centres (including estimation of nutrient intake by dietary logs for adequacy of dietary preparation), we aimed to assess the predictive utility of nutrient intake in achieving MGS. METHODS AND RESULTS: Nineteen healthy participants underwent short-term KD, with FDG-PET performed after 1 and 3 days of KD (goal carbohydrate intake <20 g/day). Nutrient consumption was estimated from dietary logs using nutrition research software. The area under receiver operating characteristics (AUROC) of macronutrients (carbohydrate, fat, and protein intake) for predicting MGS was analysed. The association between 133 nutrients and 4 biomarkers [beta-hydroxybutyrate (BHB), non-esterified fatty acids, insulin, and glucagon] with myocardial glucose uptake was assessed using mixed effects regression with false discovery rate (FDR) correction. Median (25th-75th percentile) age was 29 (25-34) years, 47% were women, and 42% were non-white. Median (25th-75th percentile) carbohydrate intake (g) was 18.7 (13.1-30.7), 16.9 (10.4-28.7), and 21.1 (16.6-29.0) on Days 1-3. No macronutrient intake (carbohydrate, fat, or protein) predicted MGS (c-statistic 0.45, 0.53, 0.47, respectively). Of 133 nutrients and 4 biomarkers, only BHB was associated with myocardial glucose uptake after FDR correction (corrected P-value 0.003). CONCLUSIONS: During highly supervised, short-term KD, approximately half of patients meet strict carbohydrate goals. Yet, in healthy volunteers, dietary review does not provide reassurance for adequacy of myocardial preparation since no clear thresholds for carbohydrate or fat intake reliably predict MGS.

Clinical Management of Hypertriglyceridemia in the Prevention of Cardiovascular Disease and Pancreatitis.

PURPOSE OF REVIEW: Hypertriglyceridemia (HTG) is common and is a significant contributor to atherosclerosis and pancreatitis risk. Specific HTG treatments have had variable success in reducing atherosclerosis risk. Novel therapies for severe HTG treatment and pancreatitis risk reduction are likely to be available soon. These novel therapies are expected to have broader applications for more moderate HTG and atherosclerosis risk reduction as well. RECENT FINDINGS: NHANES 2012 data has confirmed a reduction in average triglyceride (TG) levels in the US population. Dietary modification and weight reduction when needed remain the core treatment elements for all individuals with HTG, while statin therapy is a foundational pharmacologic care for atherosclerotic cardiovascular disease (ASCVD) event risk reduction. In addition, the REDUCE-IT study provides evidence for additional benefit from the use of high-dose icosapent ethyl (IPE) on top of background medical therapy in adults with moderate HTG and ASCVD or type 2 diabetes mellitus (T2D) and additional ASCVD risk factors. However, treatment with eicosapentaenoic acid (EPA) combined with docosahexanoic acid (DHA) did not reduce ASCVD in a similar population studied in the STRENGTH trial. Furthermore, novel therapeutics targeting PPAR-ɑ, as well as ApoC-III and AngPTL3, effectively lower TG levels in individuals with moderate and severe HTG, respectively. These treatments may have applicability for reducing risk from ASCVD among individuals with chylomicronemia; in addition, ApoC-III and AngPTL3 treatments may have a role in treating individuals with the rare monogenic familial chylomicronemia syndrome (FCS) at risk for acute pancreatitis (AP). Residual ASCVD risk in individuals treated with contemporary care may be due in part to non-LDL lipid abnormalities including HTG. The findings from REDUCE-IT, but not STRENGTH, confirm that consumption of high-dose EPA may reduce ASCVD risk, while combination therapy of EPA plus DHA does not reduce ASCVD in a similar population. TG lowering likely reduces ASCVD risk in individuals with HTG, but ASCVD risk is multifactorial; the added benefit of IPE to contemporary preventive therapy is the consequence of differential non-TG biologic properties between the two fatty acids. Acute pancreatitis is more difficult to study prospectively since it is less common; however, TG lowering is likely critical for the care of at-risk individuals. Additional benefit from novel therapy that has an impact on this otherwise refractory condition is anticipated.

The Use of Subclinical Atherosclerosis Imaging to Guide Preventive Cardiology Management.

PURPOSE OF THE REVIEW: Clinical atherosclerotic cardiovascular disease (ASCVD) requires years to manifest, providing a window of opportunity for preventive cardiovascular management. Subclinical atherosclerosis imaging leverages this long latency period to estimate and improve future ASCVD risk. RECENT FINDINGS: Coronary artery calcium (CAC) scoring has the most robust data in the detection of subclinical atherosclerosis. CAC scan significantly enhances cardiovascular risk stratification in addition to traditional risk models. Coronary computed tomography angiography data show similar strengths in subclinical atherosclerosis detection in addition to plaque morphology characterization with inherent limitations. Carotid intima-media thickness and ankle-brachial index are other modalities whose predictive value becomes incremental when added to the aforementioned modalities. When added to traditional risk models, subclinical atherosclerosis imaging modalities personalize future ASCVD risk stratification and assist in the initiation and rate of intensification of preventive therapies. Emerging imaging techniques exist but further research is required for primetime clinical use.

Health-Related Quality of Life in Patients With a Left Ventricular Assist Device (QOLVAD) Questionnaire: Initial Psychometrics of a New Instrument.

BACKGROUND: Patients with a left ventricular assist device are a unique and growing population who deserve their own valid, reliable instrument for health-related quality of life. OBJECTIVE: We developed and tested the Health-Related Quality of Life with a Left Ventricular Assist Device (QOLVAD) questionnaire. METHODS: In a prospective, descriptive study, patients from 7 sites completed the QOLVAD and comparator questionnaires. Construct validity was tested using confirmatory factor analysis. Convergent validity was tested using correlations of QOLVAD scores to well-established measures of subjective health status, depression, anxiety, and meaning/faith. Reliability and test-retest reliability were quantified. RESULTS: Patients (n = 213) were 58.7 ± 13.9 years old; 81.0% were male, 73.7% were White, and 48.0% had bridge to transplant. Questionnaires were completed at a median time of 44 weeks post ventricular assist device. The 5 QOLVAD domains had acceptable construct validity (root mean square error of approximation = 0.064, comparative and Tucker-Lewis fit indices > 0.90, weighted root mean square residual = 0.95). The total score and domain-specific scores were significantly correlated with the instruments to which they were compared. Internal consistency reliability was acceptable for all subscales (α = .79-.83) except the cognitive domain (α = .66). Unidimensional reliability for the total score was acceptable (α = .93), as was factor determinacy for multidimensional reliability (0.95). Total test-retest reliability was 0.875 (P < .001). CONCLUSION: Our analysis provided initial support for validity and reliability of the QOLVAD for total score, physical, emotional, social, and meaning/spiritual domains. The QOLVAD has potential in research and clinical settings to guide decision making and referrals; further studies are needed.

Are We Overdiagnosing Acute Kidney Injury in Pediatric Patients Following Cardiac Surgery?

BACKGROUND: The use of two diagnostic criteria in the current literature has led to some degree of ambiguity in the precise diagnosis of acute kidney injury in pediatric patients undergoing surgery for congenital heart disease. This study aims to determine which criteria is the most accurate diagnostic indicator of acute kidney injury and determine whether the incidence is being overestimated based on the current criteria. METHODS: This retrospective study consisted of 389 patients with congenital heart disease from birth to 18 years, who underwent cardiac surgery. The statistical tests conducted were the student t test and chi-square test. Outcomes measured included hospital length of stay, duration of mechanical ventilation, and mortality. RESULTS: The incidence rate of acute kidney injury diagnosed by the pediatric Risk, Injury, Failure, Loss, and End-Stage Renal Disease (RIFLE) criterion was 56% compared to 24.4% for the Acute Kidney Injury Network criterion. The pediatric RIFLE criterion consists of the following subsets: risk, injury, failure, loss, and end-stage renal disease. Patients classified in the "risk" subset of the pediatric RIFLE criterion who failed to meet Acute Kidney Injury Network criterion were compared to patients without acute kidney injury. Comparison of intensive care unit outcomes between these groups lacked statistical significance for all variables except the duration of mechanical ventilation postoperatively. CONCLUSION: Although recent research in this field identified the pediatric RIFLE criterion as the most sensitive indicator of acute kidney injury, the results of this study suggest the pediatric RIFLE criterion overestimates acute kidney injury incidence and that the Acute Kidney Injury Network criterion is the more accurate diagnostic indicator.

Acute Kidney Injury and Fluid Overload in Neonates Following Surgery for Congenital Heart Disease.

BACKGROUND: Acute kidney injury (AKI) and fluid overload have been shown to increase morbidity and mortality. The reported incidence of AKI in pediatric patients following surgery for congenital heart disease is between 15% and 59%. Limited data exist looking at risk factors and outcomes of AKI or fluid overload in neonates undergoing surgery for congenital heart disease. METHODS: Neonates aged 6 to 29 days who underwent surgery for congenital heart disease and who were without preoperative kidney disease were included in the study. The AKI was determined utilizing the Acute Kidney Injury Network criteria. RESULTS: Ninety-five neonates were included in the study. The incidence of neonatal AKI was 45% (n = 43), of which 86% had stage 1 AKI. Risk factors for AKI included cardiopulmonary bypass time, selective cerebral perfusion, preoperative aminoglycoside use, small kidneys by renal ultrasound, and risk adjustment for congenital heart surgery category. There were eight mortalities (five from stage 1 AKI group, three from stage 2, and zero from stage 3). Fluid overload and AKI both increased hospital length of stay and postoperative ventilator days. CONCLUSION: To avoid increased risk of morbidity and possibly mortality, every attempt should be made to identify and intervene on those risk factors, which may be modifiable or identifiable preoperatively, such as small kidneys by renal ultrasound.