Gardner Yost

Cognitive function and left ventricular assist device implantation.

BACKGROUND Cognitive impairment is frequent in patients with heart failure (HF) and can lead to poor quality of life and increased risk of mortality. The Montreal Cognitive Assessment (MoCA) is a simple screening tool that is sensitive to mild cognitive impairment (MCI) and that has been validated in the settings of neurologic and cardiovascular disease. This study determined the extent of cognitive impairment in patients with HF undergoing evaluation for advanced surgical therapy and evaluated changes in MoCA score with follow-up cognitive assessment at 8 months after left ventricular assist device (LVAD) implantation. METHODS As part of routine assessment for LVAD candidacy, 176 patients with advanced HF were administered the MoCA; 56 patients were reevaluated 8 months after LVAD implantation. RESULTS Patients with MCI, indicated by MoCA score <26 out of 30, made up 67% of the study cohort. MCI was associated with significantly older age, higher CHADS2 (congestive HF, hypertension, age >75 years, diabetes mellitus, prior stroke or transient ischemic attack) risk score, statin use, history of stroke and hypertension, and reduced serum cholesterol levels. In 56 patients who underwent follow-up evaluation after LVAD implantation, total MoCA score and visuospatial, executive, and delayed recall cognitive domains were significantly improved. CONCLUSIONS This study assessed the use of the MoCA in patients with end-stage HF being evaluated for advanced surgical therapy. We found the MoCA to be a rapid, simple, and powerful tool for detecting cognitive impairment in these patients. MCI was highly prevalent in the cohort. Significant improvement in overall MoCA score was noted after LVAD implantation.

Short-Form Nutrition Assessment in Patients With Advanced Heart Failure Evaluated for Ventricular Assist Device Placement or Cardiac Transplantation

BACKGROUND It has been shown that malnutrition affects clinical outcomes in patients with advanced heart failure and that nutrition status, as determined by the Mini Nutritional Assessment (MNA), can be used as an independent predictor of mortality. The aim of this study was to evaluate the prognostic utility of the short-form MNA (MNA-SF) as a surrogate to the MNA in patients with advanced heart failure. METHODS Data retrospectively gathered from nutrition assessments of 162 patients were analyzed. RESULTS As defined by the MNA, the cohort included 40 (24.7%) patients classified as malnourished, 106 (65.4%) classified as at risk, and 16 (9.9%) classified as well nourished. The mortality for the groups was 37.3%, 47.4%, and 40.5%, respectively. A linear regression showed strong correlation between the MNA and MNA-SF (r = 0.778, P < .0001). A significant difference was observed in survival between the undernourished state (at risk + malnourished) and the well-nourished state, as determined by the MNA-SF (P < .001). CONCLUSIONS The MNA-SF is a rapid nutrition assessment that correlates strongly with the full-form MNA and is an independent predictor of mortality.

Neutrophil-to-Lymphocyte Ratio Predicts Outcomes in Patients Implanted with Left Ventricular Assist Devices.

The neutrophil-to-lymphocyte ratio (NLR) has been used to predict mortality in a wide range of cardiovascular diseases including acute decompensated heart failure and non-ST-elevation myocardial infarction. We investigated the prognostic utility of the NLR in patients with advanced heart failure who received left ventricular assist devices (LVADs). Two hundred seventy-three patients implanted with LVADs at our institution were divided into tertiles based on their NLR and were retrospectively analyzed. Outcomes, including survival and right ventricular (RV) failure, were compared between tertiles. The NLR was found to be an independent predictor of postoperative mortality (odds ratio [OR] = 1.159, confidence interval [CI] = 1.022–1.314, p = 0.021) and of postoperative RV failure (OR = 1.117, CI = 1.039–1.201, p = 0.003). In addition, patients in the highest NLR tertile were found to have significantly increased postoperative length of stay (tertile 1 = 20.6 ± 10.7 days, tertile 2 = 24.2 ± 20.7 days, and tertile 3 = 28.8 ± 18.6 days, p = 0.001). In conclusion, the NLR is a simple and practical method for predicting adverse outcomes including all-cause mortality and RV failure after LVAD implantation.

Changes in Spirometry After Left Ventricular Assist Device Implantation.

Left ventricular assist devices (LVADs) are increasingly being used as life-saving therapy in patients with end-stage heart failure. The changes in spirometry following LVAD implantation and subsequent unloading of the left ventricle and pulmonary circulation are unknown. In this study, we explored long-term changes in spirometry after LVAD placement. In this retrospective study, we compared baseline preoperative pulmonary function test (PFT) results to post-LVAD spirometric measurements. Our results indicated that pulmonary function tests were significantly reduced after LVAD placement (forced expiratory volume in one second [FEV1 ]: 1.9 vs.1.7, P = 0.016; forced vital capacity [FVC]: 2.61 vs. 2.38, P = 0.03; diffusing capacity of the lungs for carbon monoxide [DLCO]: 14.75 vs. 11.01, P = 0.01). Subgroup analysis revealed greater impairment in lung function in patients receiving HeartMate II (Thoratec, Pleasanton, CA, USA) LVADs compared with those receiving HeartWare (HeartWare, Framingham, MA, USA) devices. These unexpected findings may result from restriction of left anterior hemi-diaphragm; however, further prospective studies to validate our findings are warranted.

Efficacy of Inpatient Rehabilitation After Left Ventricular Assist Device Implantation.

Left ventricular assist devices (LVADs) have become an increasingly popular and effective means for treating advanced heart failure. LVAD implantation requires extensive surgery and postoperative rehabilitation. The Functional Independence Measure (FIM) has been used to quantify functional gains in numerous patient populations, including those with stroke and spinal cord injury. This study investigated functional improvements in patients undergoing LVAD implantation using the FIM score.

Psychosocial Evaluation in Patients Undergoing Left Ventricular Assist Device Implantation Using the Transplant Evaluation Rating Scale.

BACKGROUND It has been recommended that all candidates for left ventricular assist device (LVAD) implantation undergo preoperative psychologic evaluation for risk assessment. OBJECTIVE We used the transplant evaluation rating scale (TERS) that was established for pretransplant evaluation to investigate the psychosocial assessment of patients undergoing LVAD implantation. METHODS This study retrospectively analyzed data from 125 patients with advanced heart failure who were evaluated by the TERS before LVAD implantation. Postoperative follow-up included survival, total length of hospital stay, readmissions, and post-LVAD out-of-hospital days after discharge. The cohort was stratified according to the TERS scores into low-, moderate-, and high-risk groups. The outcomes were analyzed to evaluate whether the TERS score was associated with post-LVAD adverse events. RESULTS The TERS, when stratified into 3 risk groups showed significant difference in 8 of the 10 psychosocial domains (p < 0.001). The mean number of outpatient days after discharge was significantly different between the low-, moderate-, and high-risk groups (p < 0.001). All other outcomes were not significantly different. CONCLUSIONS This study showed that the TERS is successful in stratifying our patients with an LVAD into 3 risk groups, indicating the internal validity of this test. The number of out-of-hospital (outpatient) days after discharge was significantly shorter in the TERS high-risk group, which may affect the quality of life and cost of post-LVAD care.

Acoustic characterization of axial flow left ventricular assist device operation in Vitro and in Vivo

The use of left ventricular assist devices (LVADs), implantable pumps used to supplement cardiac output, has become an increasingly common and effective treatment for advanced heart failure. Although modern continuous-flow LVADs improve quality of life and survival more than medical management of heart failure, device malfunction remains a common concern. Improved noninvasive methods for assessment of LVAD function are needed to detect device complications. An electronic stethoscope was used to record sounds from the HeartMate II axial flow pump in vitro and in vivo. The data were then uploaded to a computer and analyzed using two types of acoustic analysis software. Left ventricular assist device acoustics were quantified and were related to pump speed, acoustic environment, and inflow and outflow graft patency. Peak frequency values measured in vivo were found to correlate strongly with both predicted values and in vitro measurements (r > 0.999). Plots of the area under the acoustic spectrum curve, obtained by integrating over 50 Hz increments, showed strong correlations between in vivo and in vitro measurements (r > 0.966). Device thrombosis was found to be associated with reduced LVAD acoustic amplitude in two patients who underwent surgical device exchange.

Is Diabetes Mellitus a Risk Factor for Poor Outcomes after Left Ventricular Assist Device Placement

Diabetes mellitus is associated with adverse outcomes in patients with cardiovascular diseases, including heart failure. Left ventricular assist devices (LVADs) are increasingly used as life-saving therapy for advanced heart failure. The effects of pre-LVAD diabetes on long-term outcomes after LVAD implantation are not well understood. In this study, we retrospectively evaluated the effect of existing diabetes on post-LVAD outcomes. Data on 288 LVAD recipients from 2006 through 2013 were reviewed. Patients were stratified in accordance with their histories of diabetes. Baseline demographic, laboratory, hemodynamic, and echocardiographic information before LVAD placement were reviewed, together with the post-LVAD incidence of major adverse outcomes. Kaplan-Meier analysis and Cox regression analysis were performed. Our cohort comprised 122 patients with diabetes and 166 patients without. The mean glycosylated hemoglobin A1c level in the diabetes group was 7.4% ± 1.6%. Diabetic patients at baseline had a more adverse medical profile than did nondiabetic patients. There were no differences in major outcomes between the 2 groups other than a higher incidence of hemolysis in the diabetes group: 12 (10%) vs 5 (3%); P=0.02. There was no difference in survival outcomes between the groups. Diabetic patients did not have worse survival or more adverse outcomes than did nondiabetic patients in this study, perhaps because of improved diabetes control, or improvement in biochemical derangements after normalization of cardiac output with LVAD therapy. A diagnosis of diabetes was an independent predictor of hemolysis. Further studies to evaluate the link between hemolysis and diabetes are indicated.

Nutrition Assessment With Indirect Calorimetry in Patients Evaluated for Left Ventricular Assist Device Implantation

BACKGROUND Malnutrition is known to negatively impact the clinical course of advanced heart failure and is associated with increased mortality following left ventricular assist device (LVAD) implantation. Appropriate assessment of nutrition requirements in these patients is critical in their clinical care, yet there has been little discussion on how to best determine resting energy expenditure (REE) in the hospital setting. We investigated the use of indirect calorimetry in a group of patients with advanced heart failure. MATERIALS AND METHODS Results from preoperative indirect calorimetry testing in 98 patients undergoing evaluation for LVAD candidacy were collected. REE was compared with 10 predictive equations that estimated caloric need based on a range of patient-specific demographic and clinical variables. RESULTS This study enrolled 22 female and 76 male patients with a mean age of 59.4 ± 12.5 years, body mass index of 29.6 ± 6.0 kg/m(2), and ejection fraction of 19.4 ± 6.6%. The average REE by indirect calorimetry in this group was 1610.0 ± 612.7 kcal/d. All predictive equations significantly overestimated REE. However, those equations intended for use in the critically ill demonstrated the greatest accuracy, with the Brandi equation achieving both the highest correlation (r = 0.605, P < .001) and the lowest standard error of the estimate (504.8 kcal/d). CONCLUSIONS Indirect calorimetry may be reliably and safely used to determine caloric requirements in patients with advanced heart failure. The use of predictive equations based on demographic and clinical parameters appears to generate inaccurate estimations of REE in these patients. However, equations designed for use in critically ill patients better estimate nutrition requirements than those designed for healthy individuals.

Survival on biventricular mechanical support with the Centrimag® as a bridge to decision: a single-center risk stratification

Objective: Temporary mechanical assist devices are increasingly being used as a lifesaving bridge to decision in patients requiring cardiopulmonary resuscitation. We report our single-center experience with biventricular Centrimag® pumps over a five-year period. Method: Data was retrospectively collected in consecutive patients who required biventricular support from 2008 to 2013. Patients who were supported with central cannulation using the Centrimag® system were analyzed. In addition to demographic information, data pertaining to indications, outcomes and mortality were collected. Results: The cohort consisted of 48 patients (19 women and 29 men, mean age of 56 years). The median duration of support was 14 days. The median duration to patient expiration while still on the Centrimag® was 12 days. Thirty-day survival was 56% (27/48). Nine patients were explanted to recovery, while fourteen patients were converted to a durable LVAD, two of whom were then transplanted. We stratified patients into two groups. Group I comprised patients who were either explanted to recovery, converted to durable LVAD or transplanted (23/48) and Group II consisted of patients who either died on the Centrimag® or were explanted for withdrawal of care (25/48). Statistical analysis did not reveal any clinically significant differences between the two groups in terms of age, sex, etiology, hemodynamic, co-morbidities or laboratory parameters. Conclusion: The biventricular Centrimag® can be used as a bridge to decision in patients with thirty-day survival of >50%. Parameters to predict 30-day survival in this high-risk cohort continue to remain elusive.