Therapeutic interventions for heart failure with preserved ejection fraction: A summary of current evidence

Heart failure with preserved ejection fraction (HFPEF) is common and represents a major challenge in cardiovascular medicine. Most of the current treatment of HFPEF is based on morbidity benefits and symptom reduction. Various pharmacological interventions available for heart failure with reduced ejection fraction have not been supported by clinical studies for HFPEF. Addressing the specific aetiology and aggressive risk factor modification remain the mainstay in the treatment of HFPEF. We present a brief overview of the currently recommended therapeutic options with available evidence.

The role and management of sympathetic overactivity in cardiovascular and renal complications of diabetes

Feedback activation of neurohormonal pathways in the setting of kidney or heart failure contributes to the development and progression of dysfunction in the other. Diabetes and its management independently activate these same pathogenic pathways, feeding into this vicious cycle and contributing to a poor prognosis. One of the most important of these neurohormonal pathways is the sympathetic nervous system (SNS). The activity of the SNS in increased in patients with chronic kidney disease, even in the absence of renal impairment or heart failure. There is a strong relationship between SNS overactivity and prognosis, and evidence that blockade of SNS reduces morbidity and mortality in patients with diabetes. However, modulation of SNS is underutilised as a strategy to protect both the diabetic kidney and the heart. This is partly because of the historically poor tolerability, adverse haemodynamic and metabolic effects, lack of selectivity of β-blockers and the lack of specificity of other interventions that might modify SNS activation. The advent of "vasodilating β-blockers" with better tolerability as well as more favourable effects on renal function and metabolic profiles opens the door for their more widespread utility in patients with diabetes. Radiofrequency renal sympathectomy and baroreflex activation technologies also offer exciting new ways to tackle the challenge of sympathetic overactivity.

Enterococcus avium endocarditis

We describe a rare case of Enterococcus avium endocarditis in a patient with an ovarian malignancy, and review 2 previously reported cases. We contend that Enterococcus avium bacteremia and endocarditis may be associated with gastrointestinal pathology.

Cardiorenal syndrome

The term cardiorenal syndrome (CRS) increasingly has been used without a consistent or well-accepted definition. To include the vast array of interrelated derangements, and to stress the bidirectional nature of heart-kidney interactions, we present a new classification of the CRS with 5 subtypes that reflect the pathophysiology, the time-frame, and the nature of concomitant cardiac and renal dysfunction. CRS can be generally defined as a pathophysiologic disorder of the heart and kidneys whereby acute or chronic dysfunction of 1 organ may induce acute or chronic dysfunction of the other. Type 1 CRS reflects an abrupt worsening of cardiac function (e.g., acute cardiogenic shock or decompensated congestive heart failure) leading to acute kidney injury. Type 2 CRS comprises chronic abnormalities in cardiac function (e.g., chronic congestive heart failure) causing progressive chronic kidney disease. Type 3 CRS consists of an abrupt worsening of renal function (e.g., acute kidney ischemia or glomerulonephritis) causing acute cardiac dysfunction (e.g., heart failure, arrhythmia, ischemia). Type 4 CRS describes a state of chronic kidney disease (e.g., chronic glomerular disease) contributing to decreased cardiac function, cardiac hypertrophy, and/or increased risk of adverse cardiovascular events. Type 5 CRS reflects a systemic condition (e.g., sepsis) causing both cardiac and renal dysfunction. Biomarkers can contribute to an early diagnosis of CRS and to a timely therapeutic intervention. The use of this classification can help physicians characterize groups of patients, provides the rationale for specific management strategies, and allows the design of future clinical trials with more accurate selection and stratification of the population under investigation.

Increase in Creatinine and Cardiovascular Risk in Patients with Systolic Dysfunction after Myocardial Infarction

Baseline renal function is a potent independent risk factor for adverse events after acute myocardial infarction (MI). Worsening renal function (WRF) has been shown to influence outcomes in the heart failure population, but its impact on cardiovascular risk in the post-MI period has not been well defined. For assessment of the prognostic importance of WRF, 2231 patients who had left ventricular dysfunction and were enrolled in the Survival and Ventricular Enlargement (SAVE) trial were studied. Patients were randomly assigned between 3 and 16 d (average 11 d) after acute MI to receive captopril or placebo; those with a serum creatinine of >2.5 mg/dl were excluded from SAVE. WRF was defined as an increase in creatinine of >0.3 mg/dl measured from baseline to 2 wk after randomization. The predictive value of WRF on cardiovascular morbidity and mortality was examined during 42 mo of follow-up. Paired serum creatinine measurements at baseline and 2 wk were available in 1854 patients. WRF occurred in 223 (12.0%) patients and was a stronger predictor of death (hazard ratio [HR] 1.46; 95% confidence interval [CI] 1.05 to 2.02) than baseline creatinine (HR 1.31; 95% CI 1.01 to 1.70). WRF also showed an increased risk for cardiovascular death (HR 1.62; 95% CI 1.14 to 2.30) and the composite end point (HR 1.32; 95% CI 1.03 to 1.70). When stratified by treatment, 104 (5.7%) and 116 (6.4%) patients with WRF in the placebo and captopril groups had no significant association between treatment group and WRF (P = 0.38). The risk for death associated with WRF was HR 1.63 (95% CI 1.05 to 2.52) in the placebo group compared with HR 1.33 (95% CI 0.81 to 2.21) in the captopril group (P = 0.49 for interaction). WRF as early as 2 wk after MI was not uncommon (12.0%) and was associated with increased mortality in patients without renal dysfunction at baseline. Patients who received captopril did not demonstrate more WRF than patients who received placebo. Monitoring serum creatinine in patients during the first few weeks after MI may help to identify those who are at highest risk and guide effective long-term therapeutic choices.

Association of QRS duration and outcomes after myocardial infarction: the VALIANT trial

BACKGROUND

Prolongation of the QRS duration has been shown to be associated with adverse outcomes among heart failure (HF) patients. The association of QRS duration with clinical outcomes in the post-myocardial infarction (MI) setting is less well defined.

OBJECTIVES

To assess the prognostic significance of QRS duration prolongation on initial electrocardiogram after acute MI.

METHODS

QRS duration was measured in 403 patients with MI complicated by left ventricular dysfunction, signs or symptoms of HF, or both, who were enrolled in the Valsartan in Acute Myocardial Infarction (VALIANT) echo study. The cohort was divided into quartiles of QRS duration (<75 ms, 75-88 ms, 89-108 ms, >108 ms). The number of clinical events were determined and compared across the groups.

RESULTS

Increasing QRS duration is associated with a higher incidence of HF, sudden death (SD), and cardiovascular (CV) death (P-trend <0.05) but not with stroke or recurrent MI. The univariate relative risks for HF, SD, and CV death with increasing QRS duration quartiles were 1.31 (95% CI, 1.06-1.64), 1.57 (95% CI, 1.03-2.40), and 1.31 (95% CI, 1.03-1.66), respectively, but QRS duration did not remain independently predictive of adverse outcome after adjusting for the 10 most predictive baseline covariates. Baseline end-diastolic and end-systolic volumes were larger and ejection fraction was lower in the higher QRS quartile groups.

CONCLUSIONS

Prolonged QRS duration, even within the normal range, is associated with larger ventricular volumes, reduced systolic function, and an increased risk for development of HF, SD, and CV death after MI but appears to be a marker, rather than an independent predictor, for increased risk.

Influence of ejection fraction on cardiovascular outcomes in a broad spectrum of heart failure patients

BACKGROUND

Left ventricular function is a principal determinant of cardiovascular risk in patients with heart failure. The growing number of patients with preserved systolic function heart failure underscores the importance of understanding the relationship between ejection fraction and risk.

METHODS AND RESULTS

We studied 7599 patients with a broad spectrum of symptomatic heart failure enrolled in the Candesartan in Heart failure: Assessment of Reduction in Mortality and morbidity (CHARM) Program. All patients were randomized to candesartan at a target dose of 32 mg once daily or matching placebo and followed up for a median of 38 months. We related left ventricular ejection fraction (LVEF), measured before randomization at the sites, to cardiovascular outcomes and causes of death. Mean LVEF in patients enrolled in CHARM was 38.8+/-14.9% (median LVEF 36%). Patients with lower LVEF tended to have higher baseline New York Heart Association class. The hazard ratio for all-cause mortality increased by 39% for every 10% reduction in ejection fraction below 45% (hazard ratio 1.39, 95% CI 1.32 to 1.46), with adjustment for baseline covariates. All-cause mortality, cardiovascular death, and all components of cardiovascular death declined with increasing ejection fraction until an ejection fraction of 45%, after which the risk of these outcomes remained relatively stable with increasing LVEF. The absolute change in rate per 100 patient-years for each 10% reduction in LVEF was greatest for sudden death and heart failure-related death. The effect of candesartan in reducing cardiovascular outcomes was consistent across LVEF categories.

CONCLUSIONS

LVEF is a powerful predictor of cardiovascular outcome in heart failure patients across a broad spectrum of ventricular function. Nevertheless, once elevated to a range above 45%, ejection fraction does not further contribute to assessment of cardiovascular risk in heart failure patients.

Cytomegalovirus cholangitis presenting with recurrent hemobilia

Cytomegalovirus (CMV) cholangitis is a rare manifestation of CMV infection that has previously been described only in HIV-infected patients and solid-organ-transplant recipients. Reported here is a case of CMV cholangitis that occurred in a patient on chronic corticosteroid therapy who presented with recurrent hemobilia and biliary obstruction and was successfully treated with ganciclovir and cholecystostomy. A search of the medical literature revealed no previous case of this kind.

Chronic kidney disease and automatic reporting of estimated glomerular filtration rate: a position statement

The systematic staging of chronic kidney disease (CKD) by glomerular filtration measurement and proteinuria has allowed the development of rational and appropriate management plans. One of the barriers to early detection of CKD is the lack of a precise, reliable and consistent measure of kidney function. The most common measure of kidney function is currently serum creatinine concentration. It varies with age, sex, muscle mass and diet, and interlaboratory variation between measurements is as high as 20%. The reference interval for serum creatinine concentration includes up to 25% of people (particularly thin, elderly women) who have an estimated glomerular filtration rate (eGFR) that is significantly reduced (< 60 mL/min/1.73 m). The recent publication of a validated formula (MDRD) to estimate GFR from age, sex, race and serum creatinine concentration, without any requirement for measures of body mass, allows pathology laboratories to "automatically" generate eGFR from data already acquired. Automatic laboratory reporting of eGFR calculated from serum creatinine measurements would help to identify asymptomatic kidney dysfunction at an earlier stage. eGFR correlates well with complications of CKD and an increased risk of adverse outcomes such as cardiovascular morbidity and mortality. We recommend that pathology laboratories automatically report eGFR each time a serum creatinine test is ordered in adults. As the accuracy of eGFR is suboptimal in patients with normal or near-normal renal function, we recommend that calculated eGFRs above 60 mL/min/1.73 m be reported by laboratories as "> 60 mL/min/1.73 m", rather than as a precise figure.

Plasma renin and angiotensin levels in human hypertension following treatment

1. The levels of plasma renin activity or concentration and plasma angiotensin were similar in normotensive subjects and in untreated or treated essential hypertensives.

2. There was a close relationship between plasma renin activity and plasma renin concentration and between these and plasma angiotensin. This suggests that there were no abnormalities in renin substrate or renin kinetics in human essential hypertension.

3. Ganglion blockade did not change the plasma renin levels but α-adrenergic blockade caused a significant rise in plasma catecholamines and plasma renin without change in blood pressure.

4. Both acute and chronic β-adrenergic blockade were associated with a fall in blood pressure and small but significant falls in plasma renin levels.