Endothelial nitric oxide synthase genotype is associated with pulmonary hypertension severity in left heart failure patients

The biological mechanisms behind the development of pulmonary hypertension in the setting of left heart failure (HF-PH), including combined pre- and post-capillary pulmonary hypertension (Cpc-PH), remains unclear. This study aimed to use candidate polymorphisms in nitric oxide synthase (NOS) genes to explore the role of NOS in HF-PH. DNA samples from 118 patients with HF-PH were genotyped for the NOS3 rs1799983 and NOS2 rs3730017 polymorphisms. A multiple regression model was used to compare hemodynamic measurements between genotype groups. Patients with the T/T genotype at rs1799983 possessed a nearly 10 mmHg increased transpulmonary gradient (TPG) compared to those with other genotypes (P = 0.006). This finding was replicated in an independent cohort of 94 HF-PH patients (P = 0.005). However, when tested in a cohort of 162 pre-capillary pulmonary arterial hypertension patients, no association was observed. In a combined analysis of both HF-PH cohorts, mean pulmonary artery pressure (mPAP), diastolic pulmonary gradient (DPG), and CpcPH status were also associated with rs1799983 genotype (P = 0.005, P = 0.03, and P = 0.02, respectively). In patients with HF-PH, the NOS3 rs1799983 polymorphism is associated with TPG, and potentially mPAP and DPG as well. These findings suggest that endothelial NOS (encoded by NOS3) may be involved in the pulmonary vascular remodeling observed in Cpc-PH and warrants further study.

Racial Differences in Characteristics and Outcomes of Patients With Heart Failure and Preserved Ejection Fraction in the Treatment of Preserved Cardiac Function Heart Failure Trial

Background:

Black patients have been shown to have different baseline characteristics and outcomes compared with nonblack patients in cohort studies. However, few studies have focused on heart failure (HF) with preserved ejection fraction (HFpEF) patients. We aimed to determine the difference in cardiovascular outcomes in black and nonblack patients with HFpEF and to determine the relative efficacy and safety of spironolactone in black and nonblack patients.

Methods and Results:

Patients with HFpEF, randomized to spironolactone versus placebo in the TOPCAT trial (Treatment of Preserved Cardiac Function Heart Failure With an Aldosterone Antagonist) in North and South America, were grouped according to self-described black and nonblack race. Black HFpEF patients (n=302) were younger and were more likely to have diabetes mellitus and hypertension than nonblack patients but had similar HFpEF severity. Black patients had higher risk for the primary outcome (hazard ratio [HR], 1.34; 95% confidence interval, 1.06–1.71; P =0.02) and first HF hospitalization (HR, 1.51; 95% confidence interval, 1.167–1.97; P =0.002)], but no significant difference in cardiovascular mortality risk (HR, 0.78; 95% confidence interval, 0.51–1.20; P =0.326). In black and nonblack patients, randomization to spironolactone conferred similar efficacy in the primary outcome (HR, 0.83 versus 0.79; P for interaction=0.49), HF hospitalization (HR, 0.67 versus 0.82; P for interaction=0.76), and cardiovascular mortality ( P for interaction=0.19). The risk of hyperkalemia and worsening renal function with spironolactone and study drug adherence were also similar.

Conclusions:

Black patients with HFpEF have a higher HF hospitalization risk than nonblack patients, but spironolactone is similarly effective and safe in both groups.

Clinical Trial Registration:

URL: https://www.clinicaltrials.gov . Unique identifier: NCT00094302.

Cancer antigen-125 and risk of atrial fibrillation: a systematic review and meta-analysis

Background

Cancer antigen-125 (Ca-125) is traditionally recognised as a tumour marker and its role in cardiovascular diseases has been studied only in recent years. Whether Ca-125 is elevated in patients with atrial fibrillation (AF) and its levels predict the risk of AF remains controversial. Therefore, we conducted a systematic review and meta-analysis of the association between Ca-125 levels and AF.

Methods

PubMed and EMBASE databases were searched until 1 June 2017 for studies that evaluated the association between Ca-125 and AF. Inclusion criteria included studies that compare Ca-125 in patients with and without AF, or those reporting HRs/ORs for risk of AF stratified by Ca-125 levels.

Results

A total of 39 entries were retrieved from the databases, of which 10 studies were included in the final meta-analysis. Ca-125 was significantly higher in patients with AF compared with those in sinus rhythm (mean difference=16 U/mL, 95% CI 2 to 30 U/mL, P<0.05; I²: 98%). Ca-125 significantly increased the risk of AF (HR: 1.39, 95% CI 1.06 to 1.82, P<0.05; I²: 84%).

Conclusion

Ca-125 was significantly higher in patients with AF than in those in sinus rhythm, and high Ca-125 is predictive of AF occurrence. However, the high heterogeneity observed means there is an uncertainty in the relationship between Ca-125 and AF, which needs to be confirmed by larger prospective studies.

Left Ventricular global longitudinal strain predicts heart failure readmission in acute decompensated heart failure

Background

The goal of this study was to determine if left ventricular (LV) global longitudinal strain (GLS) predicts heart failure (HF) readmission in patients with acute decompensated heart failure.

Methods and results

Two hundred ninety one patients were enrolled at the time of admission for acute decompensated heart failure between January 2011 and September 2013. Left ventricle global longitudinal strain (LV GLS) by velocity vector imaging averaged from 2, 3 and 4-chamber views could be assessed in 204 out of 291 (70%) patients. Mean age was 63.8 ± 15.2 years, 42% of the patients were males and 78% were African American or Hispanic. Patients were followed until the first HF hospital readmission up to 44 months. Patients were grouped into quartiles on the basis of LV GLS. Kaplan-Meier curves showed significantly higher readmission rates in patients with worse LV GLS (log-rank p < 0.001). After adjusting for age, sex, history of ischemic heart disease, dementia, New York Heart Association class, LV ejection fraction, use of angiotensin converting enzyme inhibitors or angiotensin receptor blockers, systolic and diastolic blood pressure on admission and sodium level on admission, worse LV GLS was the strongest predictor of recurrent HF readmission (p < 0.001). The ejection fraction was predictive of readmission in univariate, but not in multivariate analysis.

Conclusion

LV GLS is an independent predictor of HF readmission after acute decompensated heart failure with a higher risk of readmission in case of progressive worsening of LV GLS, independent of the ejection fraction.

Left ventricular global longitudinal strain predicts mortality and heart failure admissions in African American patients

BACKGROUND

Several studies have demonstrated the importance of left ventricular (LV) global longitudinal strain (GLS) as a reliable prognostic indicator in patients with heart failure (HF). These studies have included few African American (AA) patients, despite the growing prevalence and severity of HF in this patient population.

HYPOTHESIS

LV GLS predicts long-term HF admission and all-cause mortality in AA patients with chronic HF on optimal guideline-directed medical therapy (GDMT).

METHODS

We enrolled 207 AA adults, age 56 ± 14.5 years, with New York Heart Association (NYHA) class I through III HF on optimal GDMT from the University of Illinois HF clinic between November 2001 and February 2014. LV GLS was assessed by velocity vector imaging using 2-, 3-, and 4-chamber views. Patients were followed for HF admissions and death for 3 ± 3.0 years. LV GLS value of -7.95 was used as the optimal cutoff point that maximizes sensitivity and specificity RESULTS: LV GLS < -7.95% was significantly associated with higher all-cause mortality and HF admissions in Kaplan-Meier survival curves (log-rank P < 0.001). After incorporation in multivariate Cox proportional hazard models, GLS < -7.95% was found to be an independent predictor of all-cause mortality (hazard ratio [HR] = 4.04; 95% confidence interval [CI]: 1.07-15.32; P = 0.04] and HF admissions (HR = 3.86; 95% CI: 1.38-10.77; P = 0.010).

CONCLUSIONS

In AA patients with chronic stable HF on GDMT, more impaired LV GLS (< -7.95%) is a strong and independent predictor of long-term all-cause mortality and HF admissions.

Circulating Procollagen Type III N-Terminal Peptide and Mortality Risk in African Americans With Heart Failure

BACKGROUND

Procollagen type III N-terminal peptide (PIIINP) is a biomarker of cardiac fibrosis that is associated with heart failure prognosis in whites. Its prognostic significance in African Americans is unknown. We sought to determine whether PIIINP is associated with outcomes in African Americans with heart failure.

METHODS AND RESULTS

Blood was collected from 138 African Americans with heart failure for determining PIIINP and genetic ancestry, and patients were followed prospectively for death or hospitalization for heart failure. PIIINP was inversely correlated with West African ancestry (R(2) = 0.061; P = .010). PIIINP > 4.88 ng/mL was associated with all-cause mortality on univariate (hazard ratio [HR] 4.9, 95% confidence interval [CI] 2.2-11.0; P < .001) and multivariate (HR 5.8; 95% CI 1.9-17.3; P = .002) analyses over a median follow-up period of 3 years. We also observed an increased risk for the combined outcome of all-cause mortality or hospitalization for heart failure with PIIINP > 4.88 ng/mL on univariate (HR 2.6, 95% CI 1.6-5.0; P < .001) and multivariate (HR 2.4, 95% CI 1.2-4.7; P = .016) analyses.

CONCLUSIONS

High circulating PIIINP is associated with poor outcomes in African Americans with chronic heart failure, suggesting that PIIINP may be useful in identifying African Americans who may benefit from additional therapy to combat fibrosis as a means of improving prognosis.

Abstract 315: Anemia predicts 30-Day Hospital Readmission for Heart Failure in African Americans

Background: Anemia is a frequently encountered comorbidity that affects both death and hospitalization in patients with heart failure (HF). The effect of anemia on 30-day hospital readmission in African Americans (AA) with HF has not been studied.

Methods: We retrospectively enrolled all 243 (61% female) self-reported AA adults admitted to the University of Illinois at Chicago hospital with the diagnosis of HF from January 2011 to December 2012. Extensive medical chart reviews were performed.

Results: The prevalence of anemia with hemoglobin (Hb) <12g/dl was 64.6%. After adjusting for factors known to affect readmission (table), lower Hb (<12g/dl) levels were associated with increased 30-day readmission rates (OR 0.814, 95% CI 1.6-20.7, p=0.008) in a Cox proportional hazard logistic regression model.

Conclusion: Lower Hb levels are associated with higher 30-day readmission rates in hospitalized AA patients with HF. Interventions towards appropriate treatment and prevention of anemia in AA with HF might reduce their readmission rates and improve their outcome.

Association of aldosterone synthase polymorphism (CYP11B2 -344T>C) and genetic ancestry with atrial fibrillation and serum aldosterone in African Americans with heart failure

The objective of this study was to examine the extent to which aldosterone synthase genotype (CYP11B2) and genetic ancestry correlate with atrial fibrillation (AF) and serum aldosterone in African Americans with heart failure. Clinical data, echocardiographic measurements, and a genetic sample for determination of CYP11B2 -344T>C (rs1799998) genotype and genetic ancestry were collected from 194 self-reported African Americans with chronic, ambulatory heart failure. Genetic ancestry was determined using 105 autosomal ancestry informative markers. In a sub-set of patients (n = 126), serum was also collected for determination of circulating aldosterone. The CYP11B2 -344C allele frequency was 18% among the study population, and 19% of patients had AF. Multiple logistic regression revealed that the CYP11B2 -344CC genotype was a significant independent predictor of AF (OR 12.7, 95% CI 1.60-98.4, p = 0.0150, empirical p = 0.011) while holding multiple clinical factors, left atrial size, and percent European ancestry constant. Serum aldosterone was significantly higher among patients with AF (p = 0.036), whereas increased West African ancestry was inversely correlated with serum aldosterone (r = -0.19, p = 0.037). The CYP11B2 -344CC genotype was also overrepresented among patients with extreme aldosterone elevation (≥90th percentile, p = 0.0145). In this cohort of African Americans with chronic ambulatory heart failure, the CYP11B2 -344T>C genotype was a significant independent predictor of AF while holding clinical, echocardiographic predictors, and genetic ancestry constant. In addition, increased West African ancestry was associated with decreased serum aldosterone levels, potentially providing an explanation for the lower risk for AF observed among African Americans.

Feasibility of implementing a comprehensive warfarin pharmacogenetics service

STUDY OBJECTIVE

To determine the procedural feasibility of a pharmacist-led interdisciplinary service for providing genotype-guided warfarin dosing for hospitalized patients newly starting warfarin.

DESIGN

Prospective observational study.

SETTING

A 438-bed tertiary care hospital affiliated with a large academic institution.

PATIENTS

Eighty patients who started warfarin therapy and were managed by a newly implemented pharmacogenetics service.

INTERVENTION

All patients received routine warfarin genotyping and clinical pharmacogenetics consultation.

MEASUREMENTS AND MAIN RESULTS

The primary outcomes were percentage of genotype-guided dose recommendations available prior to the second warfarin dose and adherence of the medical staff to doses recommended by the pharmacogenetics service. Of 436 genotype orders placed during the first 6 months of the service, 190 (44%) were deemed appropriate. For the 80 patients on the service who consented to data collection, 76% of the genotypes were available prior to the second warfarin dose. The median (range) time from genotype order to genotype result was 26 hours (7-80 hrs), and the time to genotype-guided dose recommendation was 30 hours (7-80 hrs). A total of 73% of warfarin doses ordered by the medical staff were within 0.5 mg of the daily dose recommended by the pharmacogenetics consult service.

CONCLUSION

Providing routine genotype-guided warfarin dosing supported by a pharmacogenetics consult service is feasible from a procedural standpoint, with most genotypes available prior to the second warfarin dose and good adherence to genotype-guided dose recommendations by the medical staff.

Hospital compliance with performance measures and 30-day outcomes in patients with heart failure

BACKGROUND

In 2005, the American College of Cardiology/American Heart Association published performance measures to provide a standard of care for hospitalized patients with heart failure (HF). Despite increasing compliance with these measures, hospital mortality and readmission rates remain stagnant. Whether compliance with HF performance measures improves patient outcomes at the hospital level is unclear.

METHODS

We evaluated compliance with HF performance measures at 3,655 US hospitals. Patients admitted with a diagnosis of HF in 2008 were identified using the US Department of Health and Human Services Hospital Compare database. Compliance with 4 specific performance measures was examined: evaluation of left ventricular systolic function, administration of angiotensin-converting enzyme inhibitor I or angiotensin-receptor blocker for left ventricular systolic dysfunction, offering smoking cessation advice and counseling, and providing discharge instructions. Thirty-day mortality and readmission rate were recorded.

RESULTS

Hospitals reporting greater compliance with the 4 performance measures had significantly lower 30-day mortality rates. However, these hospitals were also located in areas of higher socioeconomic status and treated higher volumes of patients with HF. After adjusting for socioeconomic and hospital factors, only evaluation of left ventricular systolic function was associated with lower 30-day mortality, and evaluation of left ventricular systolic function and smoking cessation counseling were associated with lower readmission rates.

CONCLUSIONS

We found that socioeconomic factors and hospital volume were stronger predictors of mortality than compliance with HF performance measures. After adjusting for socioeconomic factors and hospital volume, only 1 of the 4 performance measures was associated with lower 30-day mortality and 2 were associated with lower readmissions.

Comparison of rate control versus rhythm control for management of atrial fibrillation in patients with coexisting heart failure: a cost-effectiveness analysis

STUDY OBJECTIVE

To compare lifetime costs and health outcomes of rate control versus rhythm control for management of atrial fibrillation in patients with coexisting heart failure from the third-party payer perspective.

DESIGN

A Markov decision analysis model constructed from costs, utility, and transition probability inputs obtained from randomized clinical trials and publically available databases.

PATIENTS

A simulated cohort aged 65 years or older with persistent or paroxysmal atrial fibrillation and heart failure.

MEASUREMENTS AND MAIN RESULTS

Markov states for rhythm control were cardioversion plus amiodarone and maintenance amiodarone, and those for rate control were β-blocker, digoxin, and calcium channel blocker. Transition states included treatment success, hospitalizations for atrial fibrillation and/or heart failure, and severe adverse effects. Economic inputs included cost for drugs, cost of hospitalizations for atrial fibrillation and/or heart failure, and cost of management of severe adverse effects. Costs were measured in 2009 U.S. dollars, and clinical outcomes in quality-adjusted life-years (QALYs). One-way and multivariable sensitivity analyses were conducted. Uncertainty intervals (UIs) were obtained from probabilistic sensitivity analyses. Rate control was found to be less costly and more effective than rhythm control. Base case and probabilistic sensitivity analyses cost and effectiveness values for rate control were $7231 (95% UI $5517-9016) and 2.395 QALYs (95% UI 2.366-2.424 QALYs); whereas those for rhythm control were $16,291 (95% UI $11,033-21,434) and 2.197 QALYs (95% UI 2.155-2.237 QALYs). No critical values were found for any model parameters in the one-way sensitivity analyses. The cost-effectiveness acceptability curves showed that rate control was considered cost-effective in 100% of cases at willingness-to-pay ratios between $0 and $200,000/QALY.

CONCLUSION

Rate control is less costly and more effective than rhythm control and should be the initial treatment for atrial fibrillation among patients with coexisting heart failure.

Abstract P3: Socioeconomic Status a Better Predictor of Heart Failure Outcomes than Performance Measures

BACKGROUND ACC/AHA published performance measures for patients admitted to hospitals with heart failure (HF) in 2005 with the goal to provide a standard of care. Hospitals have made significant changes to be compliant with these recommendations, however, there are limited data evaluating if these measures are responsible for decreasing morbidity and mortality.

METHODS The US Department of Health and Human Services Hospital Compare database was used to identify patients admitted with a diagnosis of HF in 2008. Hospitals were excluded if they treated fewer than 25 HF patients or there was incomplete data collected. Inpatient performance measures for HF were defined as: evaluation of left ventricular (LV) systolic function, angiotensin-converting enzyme inhibitors (ACE-I) or angiotensin-receptor blockers (ARB) for LV systolic dysfunction, smoking cessation counseling, and discharge instructions. Risk-adjusted 30-day mortality and readmission rates were also collected. Using hospital zip codes, catchment demographic data was correlated using US Census Bureau data from 2000. Statistical analysis was performed using ANOVA and multiple regression.

RESULTS Analyses included 3,659 hospitals treating 1,059,640 patients. Hospitals reporting greater compliance with performance measures had significantly lower 30-day mortality and readmission rates. However, after controlling for individual measures and demographics, socioeconomic status consistently had a significant association with mortality and readmission rates. Only ACE-I/ARB use was associated with a lower readmission rate (p<0.001) for performance measures.

CONCLUSION This study found that multiple socioeconomic factors but only 1 of 4 HF performance measures are significant predictors of improved HF outcomes. Further research to determine appropriate metrics of quality care for HF is necessary.

Association of aldosterone concentration and mineralocorticoid receptor genotype with potassium response to spironolactone in patients with heart failure

STUDY OBJECTIVE

To identify patient-specific factors associated with spironolactone-induced potassium level elevation in patients with heart failure.

DESIGN

Prospective cohort study.

SETTING

Two adult heart failure clinics.

PATIENTS

Sixty-two adult (mean +/- SD age 54 +/- 16 yrs) aldosterone antagonist-naïve patients with heart failure.

INTERVENTION

Patients received spironolactone 12.5 mg/day, titrated to 25 mg/day if tolerated.

MEASUREMENTS AND MAIN RESULTS

Blood samples were obtained at baseline, 1 week after spironolactone initiation, and 1 week after spironolactone dose titration for assessment of baseline aldosterone level, serum chemistry, and angiotensinogen (AGT) c.-6G>A and p.M268T and mineralocorticoid receptor (NR3C2) c.215C>G and p.I180V genotypes. Patient characteristics, laboratory values, and genotypes were compared between those whose potassium levels increased by more than 0.5 mEq/L (15 patients) and those with lower potassium level elevations (47 patients) after spironolactone initiation and dose titration. Patients with a greater potassium level elevation had a higher mean +/- SD aldosterone concentration (178 +/- 92 vs 102 +/- 57 pg/ml, p=0.007) and NR3C2 215G allele frequency (50% vs 22%, p<0.01). Aldosterone concentrations positively correlated with diuretic dose (r=0.313, p=0.014) and negatively correlated with serum potassium level (r= -0.319, p=0.012). On regression analysis, factors predictive of potassium level increases greater than 0.5 mEq/L with spironolactone were aldosterone level greater than 150 pg/ml (odds ratio [OR] 30, 95% confidence interval [CI] 3.2-287] and NR3C2 215G carrier status (OR 17, 95% CI 1.6-167).

CONCLUSION

Our data suggest that potassium should be monitored with particular caution when spironolactone is started in patients with heart failure who have evidence of elevated aldosterone levels, such as high diuretic requirements, or the NR3C2 215G allele.

Using Impedance Cardiography to Assess Left Ventricular Systolic Function via Postural Change in Patients With Heart Failure

For the diagnosis and management of heart failure, it would be useful to have a simple point-of-care test for assessing ventricular function that could be performed by a nurse. An impedance cardiography (ICG) parameter called systolic amplitude (SA) can serve as an indicator of left ventricular systolic function (LVSF). This study tested the hypothesis that patients with normal LVSF should have a significant increase in SA in response to an increase in end-diastolic volume caused by postural change from sitting upright to supine, while patients with depressed LVSF associated with heart failure should have a minimal increase or a decrease in SA from upright to supine. ICG data were obtained in 12 patients without heart disease and with normal LVSF and 18 patients with clinically diagnosed heart failure. Consistent with the hypothesis, patients with normal LVSF had a significant increase in SA from upright to supine, whereas heart failure patients had a minimal increase or a decrease in SA from upright to supine. This ICG procedure may be useful for monitoring the trend of patient response to titration of beta blockers and other medications. ICG potentially could be used to detect worsening LVSF and provide a means of measurement for adjusting treatment.

Six minute walk test predicts long-term all-cause mortality and heart failure rehospitalization in African-American patients hospitalized with acute decompensated heart failure

BACKGROUND

The prognostic value of the 6-minute walk test (6MWT) has been described in patients with heart failure (HF); however, limited data are available in an African-American (AA) population. We prospectively evaluated the usefulness of the 6MWT in predicting mortality and HF rehospitalization in AA patients with acute decompensated HF.

METHODS AND RESULTS

Two hundred AA patients (63.1% men, mean age 55.7 +/- 12.9 years) with acute decompensated HF were prospectively studied. Patients were followed to assess 40-month all-cause mortality and 18-month HF rehospitalization. The median distance walked on the 6MWT was 213 m. Of the 198 patients with available mortality data, 59 patients (29.8%) died. Of the 191 patients with available rehospitalization data, 114 (59.7%) were rehospitalized for worsening HF. For patients who walked <or=200 m during the 6MWT, mortality was 41% compared with 19% in patients who walked >200 m (P = .001). For patients who walked <or=200 m during the 6MWT, HF rehospitalization was 68% compared with 52% in those who walked >200 m (P = .027). Multivariate Cox regression analysis showed that 6MWT distance <or=200 m was the strongest predictor of mortality (adjusted hazard ratio [HR], 2.14; confidence interval [CI], 1.20 to 3.81; P = .01) and HF rehospitalization (adjusted HR, 1.62; CI, 1.10 to 2.39; P = .015).

CONCLUSIONS

In AA patients hospitalized with acute decompensated HF, 6MWT strongly and independently predicts long-term all-cause mortality and HF rehospitalization.

Markers of cardiac collagen turnover are similar in patients with mild and more severe symptoms of heart failure

Cardiac fibrosis plays an important role in the pathophysiology of heart failure. The authors sought to determine whether biomarkers of cardiac fibrosis for milder clinical degrees of heart failure are comparable to those of more advanced disease. Procollagen types I and III amino-terminal peptides (PINP and PIIINP) and type I collagen telopeptide (ICTP) were compared between aldosterone-antagonistnaive patients with heart failure and New York Heart Association class I or II (n=22/23) and class III or IV (n=42/3) symptoms. Median (interquartile) range concentrations of PINP (63.3 [44.2-88.8] vs 48.6 [37.8-74.9] microg/L), ICTP (7.0 [5.4-16.8] vs 6.5 [4.7-12.7] microg/L), and PIIINP (4.7 [3.2-7.0] vs 4.7 [2.9-7.3] microg/L) were comparable between patients with mild and moderate to severe disease, respectively. These data suggest that patients with mild heart failure may have similar degrees of cardiac fibrosis to patients with more severe disease and support the examination of antifibrotic therapy, including aldosterone antagonists, in milder degrees of heart failure.

Association of β-Blocker Dose with Serum Procollagen Concentrations and Cardiac Response to Spironolactone in Patients with Heart Failure

STUDY OBJECTIVE

To determine whether beta-blocker dose influences cardiac collagen turnover and the effects of spironolactone on cardiac collagen turnover in patients with heart failure.

DESIGN

Prospective clinical study.

SETTING

Two heart failure centers.

PATIENTS

Eighty-eight spironolactone-naïve patients with heart failure who were taking beta-blockers.

INTERVENTION

In a subset of 29 patients, spironolactone was started at 12.5 mg/day, with the dosage titrated to 25 mg/day if tolerated.

MEASUREMENTS AND MAIN RESULTS

Venous blood samples were collected from each patient. Serum procollagen type I and type III aminoterminal peptides (PINP and PIIINP) were determined by radioimmunoassay and compared between the 25 patients receiving low doses (< 50% of recommended target dose) and the 63 patients receiving high doses (> or = 50% of recommended target dose) of beta-blockers. Patients receiving low-dose beta-blockers had higher mean +/- SD PIIINP concentrations (6.6 +/- 3.5 vs 4.9 +/- 2.6 microg/L, p=0.03) and tended to have higher PINP concentrations (74.0 +/- 44.1 vs 57.1 +/- 28.6 microg/L, p=0.10) compared with those receiving high doses. A repeat blood sample was collected from the 29 patients who received spironolactone after 6 months of therapy. Changes in procollagen peptides also were compared in this subset between low-dose (9 patients) and high-dose (20 patients) beta-blocker groups. Low beta-blocker doses were associated with greater reductions in concentrations of PINP (median [intraquartile range] -14.3 microg/L [-9.8 to -19.3 microg/L] vs -2.5 microg/L [5.9 to -9.8 microg/L], p=0.02) and PIIINP (-1.4 microg/L [-0.9 to -2.4 microg/L] vs 0.1 microg/L [0.9 to -1.3 microg/L], p=0.045) with spironolactone therapy than high beta-blocker doses. In addition, 100% of the patients in this subset taking low-dose beta-blockers versus only 35% taking higher doses had reductions in both markers of cardiac fibrosis.

CONCLUSION

Spironolactone may benefit patients with heart failure who cannot tolerate upward titration of beta-blocker dosages, at least in terms of its effects on cardiac remodeling.

Automated volumetric flow quantification using angle-corrected color Doppler image

We have developed a fully automated method for measuring volumetric blood flow with angle-corrected blood velocity from a color Doppler image. By computing the blood flow vector through a conduit, the angle of incidence between the direction of ultrasound beam and the direction of blood flow can be measured to correct the underestimated blood velocity. This correction immediately contributes to the improvement of measurement accuracy. The developed method also enhances the conduit identification procedure that is one of the most important factors affecting the accuracy of volumetric measurement. To evaluate the validity of the developed algorithm, experimental studies had been applied to 21 healthy subjects and 10 patients. Volumetric flows were measured from a color Doppler image of the left ventricular outflow track, which were compared with blood volumes that were measured by traditional pulsed-wave (PW)-Doppler technique. The mean stroke volume difference between two methods was -0.45 +/- 11.7 (mean +/- SD). The proposed algorithm is a viable method for determining blood flow volume in an automated fashion.

Utility of history, physical examination, electrocardiogram, and chest radiograph for differentiating normal from decreased systolic function in patients with heart failure

To determine whether clinical parameters alone can differentiate normal versus decreased systolic left ventricular function in patients with heart failure. Detailed clinical data were collected prospectively from 225 consecutive patients who were hospitalized with heart failure. Findings in patients with normal (ejection fraction > or =45%) or decreased (ejection fraction <45%) left ventricular function were compared. Systolic function was normal in 104 patients (46%) and decreased in 121 patients (54%). Patients with normal function were older (mean [+/- SD] age, 59 +/- 13 years vs. 54 +/- 13 years, P = 0.007) and more likely to be female (56% vs. 35%, P = 0.001), obese (body mass index > or =30 kg/m(2), 62% vs. 48%, P = 0.04), have marked systolic (> or =160 mm Hg, 50% vs. 27%, P <0.001) and diastolic (> or =110 mm Hg, 25% vs. 13%, P = 0.02) hypertension, and use calcium antagonists (34% vs. 14%, P = 0.001). Patients with decreased function were more likely to use alcohol (37% vs. 20%, P = 0.007), angiotensin-converting enzyme (ACE) inhibitors (85% vs. 62%, P <0.001), and digoxin (57% vs. 27%, P <0.001); and more likely to have tachycardia (51% vs. 32%, P = 0.004), rales (89% vs. 80%, P = 0.05), electrocardiographic left ventricular hypertrophy (42% vs. 22%, P = 0.002), left atrial abnormality (52% vs. 22%, P <0.001), or flow cephalization on chest radiograph (91% vs. 79%, P = 0.02). Only sex, tachycardia, and use of digoxin and ACE inhibitors were associated with ventricular function in multivariable analysis. However, the sensitivity, specificity, and predictive values for all clinical variables were low. Differences in clinical parameters in heart failure patients with decreased versus normal systolic function cannot predict systolic function in these patients, supporting recommendations that heart failure patients should undergo specialized testing to measure ventricular function.

The use of echocardiography in the critical care setting

Echocardiography has become an invaluable tool in the management of critically ill patients. Its safety and portability allow for use at the bedside to provide rapid, detailed information regarding the cardiovascular system. Echocardiography can elucidate cardiac structure and mechanical function. Recently, the power of clinical echocardiography has been augmented by the use of Doppler techniques to evaluate cardiovascular hemodynamics. An in-depth understanding of the proper use of echocardiography is a prerequisite for the intensivist.

The low-density lipoprotein cholesterol-lowering effect of pravastatin and factors associated with achieving targeted low-density lipoprotein levels in an African-American population

STUDY OBJECTIVES

To describe the low-density lipoprotein cholesterol (LDL)-lowering effect of pravastatin in African-American patients and to identify factors associated with achieving National Cholesterol Education Program (NCEP)-defined target levels.

DESIGN

Retrospectively defined cohort study.

SETTING

Large, government-owned, teaching hospital.

PATIENTS

Eighty-four African-American patients starting therapy with pravastatin in October-November 1997.

INTERVENTIONS

None.

MEASUREMENTS AND MAIN RESULTS

Whether or not target LDL concentrations were achieved was used to measure efficacy. Stepwise logistic regression identified the target LDL, baseline LDL, and baseline high-density lipoprotein cholesterol (HDL) as significant predictors of achieving the target. The proportion of patients achieving their target LDL when that target was below 160, below 130, and 100 mg/dl or below was 64%, 32%, and 13% (p=0.004), respectively. Medical record review identified the reasons for not achieving target as incorrect drug regimen, inadequate lipid monitoring, and noncompliance.

CONCLUSION

These results indicate that substantial numbers of patients receiving lipid-lowering therapy are not meeting NCEP-defined targets and that with increased drug monitoring and compliance, improvements in achieving NCEP target LDL levels could be realized.

Low high density lipoprotein levels are associated with an elevated blood viscosity

Low levels of high density lipoprotein (HDL) have been inversely correlated with blood viscosity and plasma viscosity; however, the contribution of concomitant hypertriglyceridemia may confound this association. This study evaluated the relationship between blood viscosity and HDL cholesterol in 70 subjects with fasting levels of total cholesterol <5.2 mmol/l (200 mg/dl) and triglycerides <2.3 mmol/l (200 mg/dl). Viscosity (mPa x s) was measured at 37 degrees C with a coaxial cylinder microviscometer. HDL cholesterol was inversely associated with corrected blood viscosity at 100 s(-1) (beta = -0.49, P<0.00005) and 20 s(-1) (beta = -0.38, P = 0.001) but not at 1 s(-1) (beta = -0.05, P = 0.69) using stepwise multivariate analyses. Low HDL levels are associated with an elevated blood viscosity, and this rheological abnormality may contribute to cardiovascular risk in subjects with isolated low HDL levels.