Todd M. Koelling

Evaluation study of congestive heart failure and pulmonary artery catheterization effectiveness

CONTEXT Pulmonary artery catheters (PACs) have been used to guide therapy in multiple settings, but recent studies have raised concerns that PACs may lead to increased mortality in hospitalized patients. OBJECTIVE To determine whether PAC use is safe and improves clinical outcomes in patients hospitalized with severe symptomatic and recurrent heart failure. DESIGN, SETTING, AND PARTICIPANTS The Evaluation Study of Congestive Heart Failure and Pulmonary Artery Catheterization Effectiveness (ESCAPE) was a randomized controlled trial of 433 patients at 26 sites conducted from January 18, 2000, to November 17, 2003. Patients were assigned to receive therapy guided by clinical assessment and a PAC or clinical assessment alone. The target in both groups was resolution of clinical congestion, with additional PAC targets of a pulmonary capillary wedge pressure of 15 mm Hg and a right atrial pressure of 8 mm Hg. Medications were not specified, but inotrope use was explicitly discouraged. MAIN OUTCOME MEASURES The primary end point was days alive out of the hospital during the first 6 months, with secondary end points of exercise, quality of life, biochemical, and echocardiographic changes. RESULTS Severity of illness was reflected by the following values: average left ventricular ejection fraction, 19%; systolic blood pressure, 106 mm Hg; sodium level, 137 mEq/L; urea nitrogen, 35 mg/dL (12.40 mmol/L); and creatinine, 1.5 mg/dL (132.6 micromol/L). Therapy in both groups led to substantial reduction in symptoms, jugular venous pressure, and edema. Use of the PAC did not significantly affect the primary end point of days alive and out of the hospital during the first 6 months (133 days vs 135 days; hazard ratio [HR], 1.00 [95% confidence interval {CI}, 0.82-1.21]; P = .99), mortality (43 patients [10%] vs 38 patients [9%]; odds ratio [OR], 1.26 [95% CI, 0.78-2.03]; P = .35), or the number of days hospitalized (8.7 vs 8.3; HR, 1.04 [95% CI, 0.86-1.27]; P = .67). In-hospital adverse events were more common among patients in the PAC group (47 [21.9%] vs 25 [11.5%]; P = .04). There were no deaths related to PAC use, and no difference for in-hospital plus 30-day mortality (10 [4.7%] vs 11 [5.0%]; OR, 0.97 [95% CI, 0.38-2.22]; P = .97). Exercise and quality of life end points improved in both groups with a trend toward greater improvement with the PAC, which reached significance for the time trade-off at all time points after randomization. CONCLUSIONS Therapy to reduce volume overload during hospitalization for heart failure led to marked improvement in signs and symptoms of elevated filling pressures with or without the PAC. Addition of the PAC to careful clinical assessment increased anticipated adverse events, but did not affect overall mortality and hospitalization. Future trials should test noninvasive assessments with specific treatment strategies that could be used to better tailor therapy for both survival time and survival quality as valued by patients.

The Right Ventricular Failure Risk Score: A Pre-Operative Tool for Assessing the Risk of Right Ventricular Failure in Left Ventricular Assist Device Candidates

OBJECTIVES This study sought to develop a model that estimates the post-operative risk of right ventricular (RV) failure in left ventricular assist device (LVAD) candidates. BACKGROUND Right ventricular failure after LVAD surgery is associated with increased morbidity and mortality, but identifying LVAD candidates at risk for RV failure remains difficult. METHODS A prospectively collected LVAD database was evaluated for pre-operative clinical, laboratory, echocardiographic, and hemodynamic predictors of RV failure. Right ventricular failure was defined as the need for post-operative intravenous inotrope support for >14 days, inhaled nitric oxide for > or =48 h, right-sided circulatory support, or hospital discharge on an inotrope. An RV failure risk score (RVFRS) was created from multivariable logistic regression model coefficients, and a receiver-operating characteristic curve of the score was generated. RESULTS Of 197 LVADs implanted, 68 (35%) were complicated by post-operative RV failure. A vasopressor requirement (4 points), aspartate aminotransferase > or =80 IU/l (2 points), bilirubin > or =2.0 mg/dl (2.5 points), and creatinine > or =2.3 mg/dl (3 points) were independent predictors of RV failure. The odds ratio for RV failure for patients with an RVFRS < or =3.0, 4.0 to 5.0, and > or =5.5 were 0.49 (95% confidence interval [CI] 0.37 to 0.64), 2.8 (95% CI 1.4 to 5.9), and 7.6 (95% CI 3.4 to 17.1), respectively, and 180-day survivals were 90 +/- 3%, 80 +/- 8%, and 66 +/- 9%, respectively (log rank for linear trend p = 0.0045). The area under the receiver-operating characteristic curve for the RVFRS (0.73 +/- 0.04) was superior to that of other commonly used predictors of RV failure (all p < 0.05). CONCLUSIONS The RVFRS, composed of routinely collected, noninvasive pre-operative clinical data, effectively stratifies the risk of RV failure and death after LVAD implantation.

Discharge Education Improves Clinical Outcomes in Patients With Chronic Heart Failure

Background—Although interventions combining patient education and postdischarge management have demonstrated benefits in patients with chronic heart failure, the benefit attributable to patient education alone is not known. We hypothesized that a patient discharge education program would improve clinical outcomes in patients with chronic heart failure. Methods and Results—We conducted a randomized, controlled trial of 223 systolic heart failure patients and compared the effects of a 1-hour, one-on-one teaching session with a nurse educator to the standard discharge process. Subjects were contacted by telephone at 30, 90, and 180 days to collect information about clinical events, symptoms, and self-care practices. The primary end point of the study was the total number of days hospitalized or dead in the 180-day follow-up period. Subjects randomized to receive the teaching session (n=107) had fewer days hospitalized or dead in the follow-up period (0 and 10 days, median and 75th percentiles) than did controls (n=116, 4 and 19 days; P=0.009). Patients receiving the education intervention had a lower risk of rehospitalization or death (relative risk, 0.65; 95% confidence interval, 0.45 to 0.93; P=0.018). Costs of care, including the cost of the intervention, were lower in patients receiving the education intervention than in control subjects by

Development and Validation of a Heart Atlas to Study Cardiac Exposure to Radiation Following Treatment for Breast Cancer

2823 per patient (P=0.035). Conclusions—The addition of a 1-hour, nurse educator–delivered teaching session at the time of hospital discharge resulted in improved clinical outcomes, increased self-care measure adherence, and reduced cost of care in patients with systolic heart failure.

Model for End-Stage Liver Disease Score Predicts Left Ventricular Assist Device Operative Transfusion Requirements, Morbidity, and Mortality

PURPOSE Cardiac toxicity is an important sequela of breast radiotherapy. However, the relationship between dose to cardiac structures and subsequent toxicity has not been well defined, partially due to variations in substructure delineation, which can lead to inconsistent dose reporting and the failure to detect potential correlations. Here we have developed a heart atlas and evaluated its effect on contour accuracy and concordance. METHODS AND MATERIALS A detailed cardiac computed tomography scan atlas was developed jointly by cardiology, cardiac radiology, and radiation oncology. Seven radiation oncologists were recruited to delineate the whole heart, left main and left anterior descending interventricular branches, and right coronary arteries on four cases before and after studying the atlas. Contour accuracy was assessed by percent overlap with gold standard atlas volumes. The concordance index was also calculated. Standard radiation fields were applied. Doses to observer-contoured cardiac structures were calculated and compared with gold standard contour doses. Pre- and post-atlas values were analyzed using a paired t test. RESULTS The cardiac atlas significantly improved contour accuracy and concordance. Percent overlap and concordance index of observer-contoured cardiac and gold standard volumes were 2.3-fold improved for all structures (p < 0.002). After application of the atlas, reported mean doses to the whole heart, left main artery, left anterior descending interventricular branch, and right coronary artery were within 0.1, 0.9, 2.6, and 0.6 Gy, respectively, of gold standard doses. CONCLUSIONS This validated University of Michigan cardiac atlas may serve as a useful tool in future studies assessing cardiac toxicity and in clinical trials which include dose volume constraints to the heart.

Hemodynamic and exercise performance with pulsatile and continuous-flow left ventricular assist devices.

Background— The Model for End-Stage Liver Disease (MELD) predicts events in cirrhotic subjects undergoing major surgery and may offer similar prognostication in left ventricular assist device candidates with comparable degrees of multisystem dysfunction. Methods and Results— Preoperative MELD scores were calculated for subjects enrolled in the University of Michigan Health System (UMHS) mechanical circulatory support database. Univariate and multiple regression analyses were performed to investigate the ability of patient characteristics, laboratory data (including MELD scores), and hemodynamic measurements to predict total perioperative blood product exposure and operative mortality. The ability of preoperative MELD scores to predict operative mortality was evaluated in subjects enrolled in the Interagency Registry of Mechanically Assisted Circulatory Support (INTERMACS), and results were compared with those from the UMHS cohort. The mean±SD MELD scores for the UMHS (n=211) and INTERMACS (n=324) cohorts were 13.7±6.1 and 15.2±5.8, respectively, with 29 (14%) and 19 (6%) perioperative deaths. In the UMHS cohort, median total perioperative blood product exposure was 74 units (25th and 75th percentiles, 44 and 120 units). Each 5-unit MELD score increase was associated with 15.1±3.8 units (&bgr;±SE) of total perioperative blood product exposure. Each 10-unit increase in total perioperative blood product exposure increased the odds of operative death (odds ratio, 1.05; 95% confidence interval, 1.01 to 1.10). Odds ratios, measuring the ability of MELD scores to predict perioperative mortality, were 1.5 (95% confidence interval, 1.1 to 2.0) and 1.5 (95% confidence interval, 1.1 to 2.1) per 5 MELD units for the UMHS and INTERMACS cohorts, respectively. When MELD scores were dichotomized as ≥17 and <17, risk-adjusted Cox proportional-hazard ratios for 6-month mortality were 2.5 (95% confidence interval, 1.2 to 5.3) and 2.5 (95% confidence interval, 1.1 to 5.4) for the UMHS and INTERMACS cohorts, respectively. Conclusion— The MELD score identified left ventricular assist device candidates at high risk for perioperative bleeding and mortality.

Rates of myocardial infarction and coronary artery disease and risk factors in patients treated with radiation therapy for early-stage breast cancer.

Background— Continuous-flow rotary pumps with axial design are increasingly used for left ventricular assist support. The efficacy of this design compared with pulsatile, volume displacement pumps, with respect to characteristics of left ventricular unloading, and exercise performance remains largely unstudied. Methods and Results— Thirty-four patients undergoing implantation with a pulsatile, volume displacement pump operating in a full-to-empty cycle (HeartMate XVE; Thoratec Inc, Pleasanton, Calif; n=16) or continuous-flow rotary pump with an axial design operating at a fixed rotor speed (HeartMate II; Thoratec Inc; n=18) were evaluated with right heart catheterization and echocardiography preoperatively and at 3 months postoperatively and cardiopulmonary exercise testing 3 months postoperatively. Support with either the XVE or II resulted in significant (P<0.05) increases in cardiac output and reduction in mean pulmonary artery and pulmonary wedge pressures. Exercise capacity at 3 months was similar between groups (% predicted peak o2−XVE: 46.8±10.2 versus II: 49.1±13.6). Echocardiography at 3 months demonstrated a significantly (P<0.05) greater reduction in left ventricular end-diastolic volume (−49±16% versus −35±20%), left ventricular end-systolic volume (−59±20 versus −37±21%), and percent mitral valve regurgitant volume (−99±2% versus −52±56%) for the XVE compared with II, respectively. Conclusions— The HeartMate XVE or II provided equivalent degrees of hemodynamic support and exercise capacity. The XVE was associated with greater left ventricular volume unloading. Characteristics of left ventricular pressure and volume unloading between these pump designs and mode of operation do not influence early exercise performance.

Prevalence of Cognitive Impairment in Older Adults with Heart Failure

Radiation therapy (RT), a critical component of breast‐conserving therapy for breast cancer, has been associated with coronary artery disease (CAD) in numerous older studies, but the risk may be lower with modern techniques.

Relationship between improvements in heart failure patient disease specific knowledge and clinical events as part of a randomized controlled trial.

To determine the prevalence of cognitive impairment in older adults with heart failure (HF).

Stroke Rates and Risk Factors in Patients Treated With Radiation Therapy for Early-Stage Breast Cancer

OBJECTIVE To examine the changes in performance on heart failure knowledge assessments administered before and after discharge education. METHODS We conducted a randomized controlled trial comparing the effects of a 1-h, one-on-one teaching session with a nurse educator to the standard discharge process in patients with systolic heart failure. Patients completed a 30 point heart failure knowledge questionnaire (HFKQ) prior to and 3 months after the education intervention. RESULTS Patients randomized to the nurse education intervention (n=113) demonstrated significantly higher total HFKQ score increases compared to patients receiving the standard discharge process (n=114) (median, IQR 1, 0 to 4 vs 0, -2 to 2, p=0.007). Patients experiencing death or rehospitalization in the subsequent 6 months were found to have significantly lower HFKQ scores (10, 7 to 12 vs 11, 8 to 13, p=0.002) compared to patients without a clinical event. CONCLUSION Heart failure nurse education at the time of hospital discharge results in improved patient knowledge and reduced risk of readmission. PRACTICE IMPLICATIONS Health care personnel should encourage education sessions for heart failure patients. Resources possibly need to be allocated for nurse led education sessions in heart failure patients as it improves outcomes and knowledge.