Raymond McCubrey

Lactic acidosis after cardiac transplantation: foe or common innocent bystander?

Background Lactic acidosis (LA) frequently occurs after heart transplantation (HTx). It is hypothesized to be related to inotropic support or metabolic derangements from chronic heart failure. As such, restoring hemodynamic stability with mechanical circulatory support before HTx should mitigate this problem. Our aim was to evaluate the incidence and outcomes of LA after HTx. Methods We evaluated HTx recipients January 2000 to May 2011. Post-HTx outcomes included graft dysfunction, length of intensive care unit stay, length of hospital stay, inotropic support, and survival. Results Of 143 eligible patients, 98.6% had LA, 67% severe, after HTx. Data were analyzed based on the severity of LA. Time to peak lactate, intensive care unit stay, length of hospital stay, peak glucose, inotropic dose, graft dysfunction, and survival after HTx were similar between groups. Statistically significant differences included pretransplant support (25.6% mechanical circulatory support in nonsevere vs. 44.9% severe LA), hospitalization at the time of HTx (37.2% vs. 21.4%), glucose at the time of peak lactate (182.88 ± 69.80 vs. 221.31 ± 56.91), ischemic time (187.4 ± 63.1 vs. 215.5 ± 68.1), and duration of inotrope. Conclusion Severe LA is common after HTx, though it appears to be transient and benign. Mechanical circulatory support after HTx does not prevent LA. High lactate levels are associated with longer ischemic times, longer duration of inotrope, and correspond with higher glucose levels. The underlying mechanism is yet to be satisfactorily elucidated.

Novel Stratification of Mortality Risk by Kidney Disease Stage.

Background: Chronic kidney disease (CKD) is a common disorder with a variable clinical course and it is associated with increased mortality. The Intermountain Risk Score (IMRS) is an electronic risk calculator that utilizes complete blood count (CBC) and basic metabolic panel (BMP) values to predict mortality in various healthcare populations. We hypothesized that IMRS would predict mortality in patients with CKD even with adjustment for serum phosphate and urinary albumin. Methods: Three thousand eight hundred seventy-two patients with CKD classes IIIA-V had IMRS calculated retrospectively and survival analysis was performed investigating 1- and 5-year mortality. Kaplan-Meier survival curves were generated for predefined IMRS groups of low, medium and high risk for CKD patients overall and by sex and CKD stage. Serum phosphate and urinary albumin/creatinine ratios were modeled in multivariate Cox-proportional hazard models. Receiver operator characteristic curves were used to determine c-statistics for mortality. Results: For all patients with CKD, mortality was significantly greater for those with medium- or high-risk compared to low-risk IMRS categories, among each CKD stage. Overall, IMRS was predictive of mortality at both 1 and 5 years, even when adjusted for CKD stage and predicted mortality more accurately than CKD stage alone. Albuminuria was not independently associated with mortality and serum phosphate weakly predicted mortality. Conclusion: IMRS is a strong predictor of mortality in patients with CKD and is robustly complementary to CKD stage in refining risk prediction. Given the universal availability and low cost of the CBC and BMP, IMRS may be of a substantial value in CKD risk assessment and management.

Early inpatient calculation of laboratory-based 30-day readmission risk scores empowers clinical risk modification during index hospitalization

Background Improving 30‐day readmission continues to be problematic for most hospitals. This study reports the creation and validation of sex‐specific inpatient (i) heart failure (HF) risk scores using electronic data from the beginning of inpatient care for effective and efficient prediction of 30‐day readmission risk. Methods HF patients hospitalized at Intermountain Healthcare from 2005 to 2012 (derivation: n = 6079; validation: n = 2663) and Baylor Scott & White Health (North Region) from 2005 to 2013 (validation: n = 5162) were studied. Sex‐specific iHF scores were derived to predict post‐hospitalization 30‐day readmission using common HF laboratory measures and age. Risk scores adding social, morbidity, and treatment factors were also evaluated. Results The iHF model for females utilized potassium, bicarbonate, blood urea nitrogen, red blood cell count, white blood cell count, and mean corpuscular hemoglobin concentration; for males, components were B‐type natriuretic peptide, sodium, creatinine, hematocrit, red cell distribution width, and mean platelet volume. Among females, odds ratios (OR) were OR = 1.99 for iHF tertile 3 vs. 1 (95% confidence interval [CI] = 1.28, 3.08) for Intermountain validation (P‐trend across tertiles = 0.002) and OR = 1.29 (CI = 1.01, 1.66) for Baylor patients (P‐trend = 0.049). Among males, iHF had OR = 1.95 (CI = 1.33, 2.85) for tertile 3 vs. 1 in Intermountain (P‐trend < 0.001) and OR = 2.03 (CI = 1.52, 2.71) in Baylor (P‐trend < 0.001). Expanded models using 182–183 variables had predictive abilities similar to iHF. Conclusions Sex‐specific laboratory‐based electronic health record‐delivered iHF risk scores effectively predicted 30‐day readmission among HF patients. Efficient to calculate and deliver to clinicians, recent clinical implementation of iHF scores suggest they are useful and useable for more precise clinical HF treatment.

IMPACT OF TRANSITIONING FROM SPECT TO PET ON MYOCARDIAL ISCHEMIA DETECTION: EXPERIENCE FROM A HIGH VOLUME “REAL WORLD” PRACTICE

Myocardial Perfusion Imaging (MPI) with PET technology has been shown to improve ischemia detection compared to SPECT, however limited data are available comparing the modalities in clinical practice. We report the impact of transitioning from SPECT testing to PET on the ability to assess myocardial

Practical laboratory-based clinical decision tools and associations with short-term bleeding and mortality outcomes

BACKGROUND The red cell distribution width (RDW) predicts mortality in numerous populations. The Intermountain Risk Scores (IMRS) predict patient outcomes using laboratory measurements including RDW. Whether the RDW or IMRS predicts in-hospital outcomes is unknown. METHODS The predictive abilities of RDW and two IMRS formulations (the complete blood count [CBC] risk score [CBC-RS] or full IMRS using CBC plus the basic metabolic profile) were studied among percutaneous coronary intervention patients at Intermountain (males: N = 6007, females: N = 2165). Primary endpoints were a composite bleeding outcome and in-hospital mortality. RESULTS IMRS predicted the composite bleeding endpoint (females: χ2 = 47.1, odds ratio [OR] = 1.13 per +1 score, p < 0.001; males: χ2 = 108.7, OR = 1.13 per +1 score, p < 0.001) more strongly than RDW (females: χ2 = 1.6, OR = 1.04 per +1%, p = 0.20; males: χ2 = 11.2, OR = 1.09 per +1%, p < 0.001). For in-hospital mortality, RDW was predictive in females (χ2 = 4.3, OR = 1.13 per +1%, p = 0.037) and males (χ2 = 4.4, OR = 1.11 per +1%, p = 0.037), but IMRS was profoundly more predictive (females: χ2 = 35.5, OR = 1.36 per +1 score, p < 0.001; males: χ2 = 72.9, OR = 1.40 per+1 score, p < 0.001). CBC-RS was more predictive than RDW but not as powerful as IMRS. CONCLUSIONS The IMRS, the CBC-RS, and RDW predict in-hospital outcomes. Risk score-directed personalization of in-hospital clinical care should be studied.

Adverse cardiovascular events in acute coronary syndrome with indications for anticoagulation

Objectives: Randomized acute coronary syndrome (ACS) trials testing various antithrombotic (AT) regimens have largely excluded patients with coexisting conditions and indications for anticoagulation (AC). The purpose of this study is to examine the 2-year clinical outcomes of patients with ACS with indication for AC due to venous thromboembolism (VTE) during hospitalization for the ACS event or a prior or new diagnosis of atrial fibrillation (AF) with a CHADS2 (Congestive heart failure; Hypertension; Age; Diabetes; previous ischemic Stroke) score ⩾2. Methods: ACS patients with AC indication from 2004 to 2009 were identified (n = 619). A Cox proportional hazards model was used to examine the primary efficacy outcome of major adverse cardiovascular events (MACE) including all-cause death, myocardial infarction (MI) or stroke. The primary explanatory variable was at-discharge antithrombotic strategy [single antiplatelet ± AC, dual antiplatelet (DAP) ± AC or AC only; referent DAP + AC]. Results: A total of 261 (42.2%) patients had a MACE event. AT strategy was not a significant factor for MACE (all p > 0.09). The factors associated with MACE were high mortality risk score [hazard ratio (HR)=1.87, 95% confidence interval (CI): 1.39– 2.52; p < 0.001), prior MI (HR = 1.44, 95% CI: 1.03–2.01; p= 0.033) and presentation of ST elevation MI (HR = 2.70, 95% CI: 1.61–4.51; p < 0.001) or non-ST elevation MI (HR = 1.70, 95% CI: 1.15–2.49; p < 0.001) compared with angina. Conclusions: In this real world observational study, the at-discharge AT strategy was not significantly associated with the 2-year risk of MACE. These findings do not negate the need for randomized trials to generate evidence-based approaches to management of this important population.

MYOCARDIAL STRESS FLOWS IN OBSTRUCTIVE CAD ARE HIGHER WITH REGADENOSON THAN DIPYRIDAMOLE

Cut-off myocardial blood flow values associated with clinically significant ischemia in patients undergoing PET/CT have been reported with dipyridamole. Little is reported on MBF in stenotic vessels ≥70% as compared to non-stenotic vessels using regadenoson and Rb82. 731 patients (482 males, 65

DIFFERENCES IN CORONARY FLOW RESERVES BY GENDER AND DIABETIC STATUS AS IDENTIFIED USING CARDIAC PET/CT

Existing literature is scarce regarding normal and abnormal measurements for coronary flow reserve (CFR) non-ischemic rubidium PET/CT cardiac stress perfusion scans using regadenoson as the stress agent. Here we analyze and compare global and vessel-specific CFR between diabetics (DM) and non-

How much heating is associated with magnetic resonance imaging in patients with pacemakers and implantable cardioverter defibrillators

Methods Methods: We tested the effect of MRI on local tissue heating over PM/ICD pulse generators (PGs) in a consecutive series of 34 non-thoracic scans in 30 patients (pts) enrolled in an ongoing registry study. MRI was performed with a General Electric 1.5 tesla model Signa HDXT scanner. Temperatures were taken immediately preand post-study with an infrared thermometer beamed at the center of the PG pocket and symmetrically on the opposite side of the anterior chest. Ambient temperature was set at 66°F. Pacing modes during MRI were 0D0 for intrinsic rates > 40 and D00 for rates < 40. Diffusion scan sequences were excluded in PM dependent pts. Devices were St. Jude (n = 11), Boston Scientific (n = 12) or Medtronic (n = 11). The primary endpoint was change in device-side versus control-side skin temperature.