Mild systolic dysfunction in heart failure (left ventricular ejection fraction >35%): baseline characteristics, prognosis and response to therapy in the Vasodilator in Heart Failure Trials (V-HeFT)

Pharmacological interventions for heart failure in people with chronic kidney disease

BACKGROUND

Approximately half of people with heart failure have chronic kidney disease (CKD). Pharmacological interventions for heart failure in people with CKD have the potential to reduce death (any cause) or hospitalisations for decompensated heart failure. However, these interventions are of uncertain benefit and may increase the risk of harm, such as hypotension and electrolyte abnormalities, in those with CKD.

OBJECTIVES

This review aims to look at the benefits and harms of pharmacological interventions for HF (i.e., antihypertensive agents, inotropes, and agents that may improve the heart performance indirectly) in people with HF and CKD.

SEARCH METHODS

We searched the Cochrane Kidney and Transplant Register of Studies through 12 September 2019 in consultation with an Information Specialist and using search terms relevant to this review. Studies in the Register are identified through searches of CENTRAL, MEDLINE, and EMBASE, conference proceedings, the International Clinical Trials Register (ICTRP) Search Portal and ClinicalTrials.gov.

SELECTION CRITERIA

We included randomised controlled trials of any pharmacological intervention for acute or chronic heart failure, among people of any age with chronic kidney disease of at least three months duration.

DATA COLLECTION AND ANALYSIS

Two authors independently screened the records to identify eligible studies and extracted data on the following dichotomous outcomes: death, hospitalisations, worsening heart failure, worsening kidney function, hyperkalaemia, and hypotension. We used random effects meta-analysis to estimate treatment effects, which we expressed as a risk ratio (RR) with 95% confidence intervals (CI). We assessed the risk of bias using the Cochrane tool. We applied the GRADE methodology to rate the certainty of evidence.

MAIN RESULTS

One hundred and twelve studies met our selection criteria: 15 were studies of adults with CKD; 16 studies were conducted in the general population but provided subgroup data for people with CKD; and 81 studies included individuals with CKD, however, data for this subgroup were not provided. The risk of bias in all 112 studies was frequently high or unclear. Of the 31 studies (23,762 participants) with data on CKD patients, follow-up ranged from three months to five years, and study size ranged from 16 to 2916 participants. In total, 26 studies (19,612 participants) reported disaggregated and extractable data on at least one outcome of interest for our review and were included in our meta-analyses. In acute heart failure, the effects of adenosine A1-receptor antagonists, dopamine, nesiritide, or serelaxin on death, hospitalisations, worsening heart failure or kidney function, hyperkalaemia, hypotension or quality of life were uncertain due to sparse data or were not reported. In chronic heart failure, the effects of angiotensin-converting enzyme inhibitors (ACEi) or angiotensin receptor blockers (ARB) (4 studies, 5003 participants: RR 0.85, 95% CI 0.70 to 1.02; I2 = 78%; low certainty evidence), aldosterone antagonists (2 studies, 34 participants: RR 0.61 95% CI 0.06 to 6.59; very low certainty evidence), and vasopressin receptor antagonists (RR 1.26, 95% CI 0.55 to 2.89; 2 studies, 1840 participants; low certainty evidence) on death (any cause) were uncertain. Treatment with beta-blockers may reduce the risk of death (any cause) (4 studies, 3136 participants: RR 0.69, 95% CI 0.60 to 0.79; I2 = 0%; moderate certainty evidence). Treatment with ACEi or ARB (2 studies, 1368 participants: RR 0.90, 95% CI 0.43 to 1.90; I2 = 97%; very low certainty evidence) had uncertain effects on hospitalisation for heart failure, as treatment estimates were consistent with either benefit or harm. Treatment with beta-blockers may decrease hospitalisation for heart failure (3 studies, 2287 participants: RR 0.67, 95% CI 0.43 to 1.05; I2 = 87%; low certainty evidence). Aldosterone antagonists may increase the risk of hyperkalaemia compared to placebo or no treatment (3 studies, 826 participants: RR 2.91, 95% CI 2.03 to 4.17; I2 = 0%; low certainty evidence). Renin inhibitors had uncertain risks of hyperkalaemia (2 studies, 142 participants: RR 0.86, 95% CI 0.49 to 1.49; I2 = 0%; very low certainty). We were unable to estimate whether treatment with sinus node inhibitors affects the risk of hyperkalaemia, as there were few studies and meta-analysis was not possible. Hyperkalaemia was not reported for the CKD subgroup in studies investigating other therapies. The effects of ACEi or ARB, or aldosterone antagonists on worsening heart failure or kidney function, hypotension, or quality of life were uncertain due to sparse data or were not reported. Effects of anti-arrhythmic agents, digoxin, phosphodiesterase inhibitors, renin inhibitors, sinus node inhibitors, vasodilators, and vasopressin receptor antagonists were very uncertain due to the paucity of studies.

AUTHORS' CONCLUSIONS

The effects of pharmacological interventions for heart failure in people with CKD are uncertain and there is insufficient evidence to inform clinical practice. Study data for treatment outcomes in patients with heart failure and CKD are sparse despite the potential impact of kidney impairment on the benefits and harms of treatment. Future research aimed at analysing existing data in general population HF studies to explore the effect in subgroups of patients with CKD, considering stage of disease, may yield valuable insights for the management of people with HF and CKD.

Combination of Hydralazine and Isosorbide-Dinitrate in the Treatment of Patients with Heart Failure with Reduced Ejection Fraction

The use of direct acting vasodilators (the combination of hydralazine and isosorbide dinitrate -Hy+ISDN-) in heart failure with reduced ejection fraction (HFrEF) is supported by evidence, but rarely used.However, treatment with Hy+ISDN is guideline-recommended for HFrEF patients who cannot receive either angiotensin-converting enzyme inhibitors or angiotensin receptor blockers due to intolerance or contraindication, and in self-identified African-American HFrEF patients who are symptomatic despite optimal neurohumoral therapy.The Hy+ISDN combination has arterial and venous vasodilating properties. It can decrease preload and afterload, decrease left ventricular end-diastolic diameter and the volume of mitral regurgitation, reduce left atrial and left ventricular wall tension, decrease pulmonary artery pressure and pulmonary arterial wedge pressure, increase stroke volume, and improve left ventricular ejection fraction, as well as induce left ventricular reverse remodelling. Furthermore, Hy+ISDN combination has antioxidant property, it affects endothelial dysfunction beneficially and improves NO bioavailability. Because of these benefits, this combination can improve the signs and symptoms of heart failure, exercise capacity and quality of life, and, most importantly, reduce morbidity and mortality in well-defined subgroups of HFrEF patients.Accordingly, this therapeutic option can in many cases play an essential role in the treatment of HFrEF.

Effects of beta-blockers on heart failure with preserved ejection fraction: a meta-analysis

BACKGROUND

Effects of beta-blockers on the prognosis of the heart failure patients with preserved ejection fraction (HFpEF) remain controversial. The aim of this meta-analysis was to determine the impact of beta-blockers on mortality and hospitalization in the patients with HFpEF.

METHODS

A search of MEDLINE, EMBASE, and the Cochrane Library databases from 2005 to June 2013 was conducted. Clinical studies reporting outcomes of mortality and/or hospitalization for patients with HFpEF (EF ≥ 40%), being assigned to beta-blockers treatment and non-beta-blockers control group were included.

RESULTS

A total of 12 clinical studies (2 randomized controlled trials and 10 observational studies) involving 21,206 HFpEF patients were included for this meta-analysis. The pooled analysis demonstrated that beta-blocker exposure was associated with a 9% reduction in relative risk for all-cause mortality in patients with HFpEF (95% CI: 0.87 - 0.95; P < 0.001). Whereas, the all-cause hospitalization, HF hospitalization and composite outcomes (mortality and hospitalization) were not affected by this treatment (P=0.26, P=0.97, and P=0.88 respectively).

CONCLUSIONS

The beta-blockers treatment for the patients with HFpEF was associated with a lower risk of all-cause mortality, but not with a lower risk of hospitalization. These finding were mainly obtained from observational studies, and further investigations are needed to make an assertion.

Diagnosis and management of left ventricular diastolic dysfunction in the hypertensive patient

The progression of hypertensive involvement toward heart failure includes myocardial fibrosis and changes of left ventricular (LV) geometry. In the presence of these abnormalities, diastolic abnormalities occur and are defined as LV diastolic dysfunction (DD). They include alterations of both relaxation and filling, precede alterations of chamber systolic function and can induce symptoms of heart failure even when ejection fraction is normal. The prevalence of heart failure with normal ejection fraction (HFNEF) increased over time whereas the rate of death from this disorder remained unchanged. In this view, diagnosis, prognosis, and therapeutic management of DD and HFNEF in hypertensive patients is a growing public health problem. DD may be asymptomatic and identified occasionally during a Doppler-echocardiographic examination. This tool has gained, therefore, important clinical position for diagnosis of DD. Comprehensive assessment of diastolic function should be done not by a simple classification of DD progression but by estimating the degree of LV filling pressure (FP), a true determinant of symptoms and prognosis. This can be obtained by different ultrasound maneuvers/tools but the ratio between transmitral E velocity and pulsed tissue Doppler-derived early diastolic velocity (E/e' ratio) is the most feasible and accurate. The identification of left atrial enlargement may be useful in uncertain cases. The recommended management of DD in hypertensive patients should correspond to blood pressure (BP) lowering and to the attempt of reducing LV mass and normalizing LV geometry. Prospective studies with well-defined entry criteria are needed to establish whether this approach could reflect a better prognosis.

Heart failure with preserved ejection fraction: pathophysiology, diagnosis, and treatment

Half of patients with heart failure (HF) have a preserved left ventricular ejection fraction (HFpEF). Morbidity and mortality in HFpEF are similar to values observed in patients with HF and reduced EF, yet no effective treatment has been identified. While early research focused on the importance of diastolic dysfunction in the pathophysiology of HFpEF, recent studies have revealed that multiple non-diastolic abnormalities in cardiovascular function also contribute. Diagnosis of HFpEF is frequently challenging and relies upon careful clinical evaluation, echo-Doppler cardiography, and invasive haemodynamic assessment. In this review, the principal mechanisms, diagnostic approaches, and clinical trials are reviewed, along with a discussion of novel treatment strategies that are currently under investigation or hold promise for the future.

Insulin resistance and glycemic abnormalities are associated with deterioration of left ventricular diastolic function: a cross-sectional study

BACKGROUND

Left ventricular diastolic dysfunction (LVDD) is considered a precursor of diabetic cardiomyopathy, while insulin resistance (IR) is a precursor of type 2 diabetes mellitus (T2DM) and independently predicts heart failure (HF). We assessed whether IR and abnormalities of the glucose metabolism are related to LVDD.

METHODS

We included 208 patients with normal ejection fraction, 57 (27%) of whom had T2DM before inclusion. In subjects without T2DM, an oral glucose tolerance test (oGTT) was performed. IR was assessed using the Homeostasis Model Assessment of Insulin Resistance (HOMA-IR). The lower limit of the top quartile of the HOMA-IR distribution (3.217) was chosen as threshold for IR. LVDD was verified according to current guidelines.

RESULTS

IR was diagnosed in 38 (18%) patients without a history of diabetes. The prevalence of LVDD was 92% in subjects with IR vs. 72% in patients without IR (n = 113), respectively (p = 0.013). In the IR group, the early diastolic mitral inflow velocity (E) in relation to the early diastolic tissue Doppler velocity (averaged from the septal and lateral mitral annulus, E'av) ratio (E/E'av) was significantly higher compared to those without IR (9.8 [8.3-11.5] vs. 8.1 [6.6-11.0], p = 0.011). This finding remains significant when patients with IR and concomitant T2DM based on oGTT results were excluded (E/E'av ratio 9.8 [8.2-11.1)] in IR vs. 7.9 [6.5-10.5] in those without both IR and T2DM, p = 0.014). There were significant differences among patients with and without LVDD regarding the HOMA-IR (1.71 [1.04-3.88] vs. 1.09 [0.43-2.2], p = 0.003). The HOMA-IR was independently associated with LVDD on multivariate logistic regression analysis, a 1-unit increase in HOMA-IR value was associated with an odds ratio for prevalent LVDD of 2.1 (95% CI 1.3-3.1, p = 0.001). Furthermore, the E/E'av ratio increases along the glucose metabolism status from normal glucose metabolism (7.6 [6.2-10.1]) to impaired glucose tolerance (8.8 [7.4-11.0]) and T2DM (10.5 [8.1-13.2]), respectively (p < 0.001).

CONCLUSIONS

Insulin resistance is independently associated with LVDD in subjects without overt T2DM. Patients with IR and glucose metabolism disorders might represent a target population to prevent the development of HF. Screening programs for glucose metabolism disturbances should address the assessment of diastolic function and probably IR.

Treatment of heart failure with normal ejection fraction: an inconvenient truth!

Despite use of similar drugs, outcomes of recent heart failure (HF) trials were frequently neutral in heart failure with normal left ventricular ejection fraction (HFNEF) and positive in heart failure with reduced left ventricular ejection fraction (HFREF). The neutral outcomes of HFNEF trials were often attributed to deficient HFNEF patient recruitment with inclusion of many HFREF or noncardiac patients. Patient recruitment criteria of 21 HFNEF trials were therefore reviewed in reference to diagnostic guidelines for HFNEF. In the 4 published sets of guidelines, a definite diagnosis of HFNEF required the simultaneous and obligatory presence of signs and/or symptoms of HF and evidence of normal systolic left ventricular (LV) function and of diastolic LV dysfunction. In 3 of 4 sets of guidelines, normal systolic LV function comprised both a left ventricular ejection fraction (LVEF) >50% and an absence of LV dilation. Among the 21 HFNEF trials, LVEF cutoff values ranged from 35% to 50%, with only 8 trials adhering to an LVEF >50%. Furthermore, only 1 trial specified a normal LV end-diastolic dimension as an enrollment criterion and only 7 trials required evidence of diastolic LV dysfunction. Nonadherence to diagnostic guidelines induced excessive enrollment into HFNEF trials of HF patients with eccentric LV remodeling and ischemic heart disease compared with HF patients with concentric LV remodeling and arterial hypertension. Nonadherence to guidelines also led to underpowered HFNEF trials with a low incidence of outcome events such as death or HF hospitalizations. Future HFNEF trials should therefore adhere to diagnostic guidelines for HFNEF.

Understanding heart failure with preserved ejection fraction: clinical importance and future outlook

Heart failure (HF) with preserved ejection fraction (HF-PEF) accounts for approximately one half of all HF patients admitted with acute decompensated HF and carries a significant morbidity and mortality burden. This condition, however, has been largely understudied because it is difficult to diagnose, and management guidelines are still being discussed. This article provides an overview of HF-PEF and its pathophysiology, diagnosis, and treatment, with a focus on clinical trials using renin-angiotensin-aldosterone system (RAAS) blockers. Inhibitors of the RAAS have been studied in HF-PEF to determine whether their benefits extend beyond blood pressure control. However, the 3 trials conducted to date (CHARM-Preserved, PEP-CHF, and I-PRESERVE) with candesartan, perindopril, and irbesartan, have failed to demonstrate significant morbidity and mortality benefits. Although no agent has proven statistically significant benefits in morbidity and mortality in HF-PEF, recent studies have added to the breadth of clinical data and understanding of the demographics of these patients.

Future strategies for the treatment of diastolic heart failure

It is estimated that 30% to 50% of heart failure patients have preserved systolic left ventricular (LV) function, often referred to as diastolic heart failure (DHF). Mortality is high in this patient population, and morbidity and rate of hospitalization are similar to those of patients with systolic heart failure. The management of patients with diastolic heart failure is essentially empirical, limited, and disappointing. New drugs, devices, and gene therapy based treatment options are currently under investigation. In this review, future strategies for the treatment of diastolic heart failure are discussed.

Cystatin C in acute heart failure without advanced renal impairment

BACKGROUND

The prognostic value of cystatin C relative to glomerular filtration rate (GFR) estimated by the Modification of Diet in Renal Disease Study (MDRD) equation modified for Japan has not been investigated in acute heart failure patients with normal to moderately impaired renal function. More accurate detection of mild renal impairment might improve the risk stratification of heart failure patients, especially patients with normal to moderately impaired renal function.

METHODS

Cystatin C and creatinine levels were measured on admission in 328 consecutive patients hospitalized for worsening chronic heart failure with a GFR estimated by MDRD equation modified for Japan >or=30 mL/min/1.73 m(2).

RESULTS

During a median follow-up period of 915 days, there were 52 (16%) cardiac deaths. In stepwise Cox regression analyses including cystatin C and GFR estimated by MDRD equation modified for Japan (either as continuous variables or as variables categorized into quartiles), cystatin C (P <.0001), but not GFR estimated by MDRD equation modified for Japan, was independently associated with cardiac mortality. Adjusted relative risk according to the quartiles of these markers and Kaplan-Meier analyses revealed that the cystatin C was a better marker to separate low-risk from high-risk patients. Furthermore, receiver-operating characteristic curve analyses of these markers revealed that cystatin C showed a higher precision in predicting cardiac mortality.

CONCLUSION

Measurements of cystatin C might improve early risk stratification compared with GFR estimated by MDRD equation modified for Japan in acute heart failure patients with normal to moderately impaired renal function.

Effect of statins, angiotensin-converting enzyme inhibitors, and beta blockers on survival in patients >or=65 years of age with heart failure and preserved left ventricular systolic function

About half of all patients with heart failure (HF) have preserved left ventricular systolic function. Statins, angiotensin-converting enzyme inhibitors, and beta blockers have been shown to improve survival in patients with HF and low ejection fraction. However, no large national study has investigated these agents in patients with HF and preserved left ventricular ejection fraction. We evaluated a nationwide sample of 13,533 eligible Medicare beneficiaries aged >or=65 years who were hospitalized with a primary discharge diagnosis of HF and had chart documentation of preserved left ventricular ejection fraction between April 1998 and March 1999 or between July 2000 and June 2001. In Cox proportional hazard model accounting for demographic profile, clinical characteristics, treatments, physician specialty, and hospital characteristics, discharge statin therapy was associated with significant improvements in 1- and 3-year mortality (RR 0.69, 95% confidence interval [CI] 0.61 to 0.78; RR 0.73, 95% CI 0.68 to 0.79, respectively). Irrespective of total cholesterol level or coronary artery disease status, diabetes, hypertension, and age, statin therapy was associated with significant differences in mortality rates. Similarly, angiotensin-converting enzyme inhibitors were associated with better survival at 1 year (RR 0.88, 95% CI 0.82 to 0.95) and 3 years (RR 0.93, 95% CI 0.89 to 0.98). Beta-blocker therapy was associated with a nonsignificant trend at 1 year (RR 0.93, 95% CI 0.87 to 1.10) and significant survival benefits at 3 years (RR 0.92%, 95% CI 0.87 to 0.97). In conclusion, our data demonstrate that statins, angiotensin-converting enzyme inhibitors, and beta blockers are associated with better short- and long-term survival in patients >or=65 years with HF and preserved left ventricular ejection fraction.

[Relation between QT dispersion, left ventricle systolic function and frequency of ventricular arrhythmias in coronary patients]

INTRODUCTION

QT dispersion (QTd) is a measure of non-homogeneous repolarisation of the myocardium and is used as an indicator of arrhythmogenicity.

OBJECTIVE

The aim of this study was to assess the relation between QT dispersion, left ventricle systolic function and frequency of ventricular arrhythmias in coronary patients.

METHOD

We studied 290 coronary patients, 72 with angina pectoris and 218 after myocardial infarction. Eighty-one coronary patients had frequent and complex ventricular arrhythmias (out of them 19 had ventricular tachycardia) and 209 were without arrhythmias or with infrequent ventricular premature contractions (VPC < or = 10/h). In all patients, QT dispersion, exercise test, 24-hour Holter monitoring and echocardiographic examination were performed.

RESULTS

Patients with frequent and complex ventricular arrhythmias had significantly higher values of QTd (71.8 +/- 25.5 vs 55.6 +/- 21.7 ms; p < 0.001), corrected QT dispersion (QTdc: 81.3 +/- 31.5 vs. 60.3 +/- 26.1 ms; p < 0.001 ), left ventricular end-diastolic diameter (LVEDd: 56.2 +/- 6.9 vs. 53.4 +/- 6.2 mm; p < 0.001) and left ventricular end-systolic diameter (LVESd: 39.5 +/- 6.2 vs. 36.0 +/- 6.3 mm; p < 0.001), and significantly lower values of left ventricular ejection fraction (LVEF: 47.7 +/- 13.9 vs. 55.9 +/- 11.6%; p < 0.001) in comparison to those without arrhythmias or with infrequent VPC. Patients with VT had significantly higher values of QTd and QTdc in comparison to other patients with frequent and complex ventricular arrhythmias (83.8 +/- 17.1 vs. 69.4 +/- 26.2 ms; p < 0.02 for QTd; 101.1 +/- 23.9: 77.6 +/- 31.4 ms; p < 0.005 for QTdc). There is a significant negative correlation of QTd and QTdc with LVEF, and a significant positive correlation of QTd and QTdc with inside dimensions of the left ventricle, in patients with frequent and complex ventricular arrhythmias.

CONCLUSION

The study demonstrated that patients with frequent and complex ventricular arrhythmias had significantly higher values of QTd and QTdc, as well as a higher degree of left ventricle systolic dysfunction in comparison to those without arrhythmias or with infrequent VPC.

Early heart rate recovery after exercise predicts mortality in patients with chronic heart failure

BACKGROUND

Patients with chronic heart failure (CHF) have multiple abnormalities of autonomic regulation that have been associated to their high mortality rate. Heart rate recovery immediately after exercise is an index of parasympathetic activity, but its prognostic role in CHF patients has not been determined yet.

METHODS

Ninety-two stable CHF patients (83M/9F, mean age: 51+/-12 years) performed an incremental symptom-limited cardiopulmonary exercise testing. Measurements included peak O2 uptake (VO2p), ventilatory response to exercise (VE/VCO2 slope), the first-degree slope of VO2 for the 1st minute of recovery (VO2/t-slope), heart rate recovery [(HRR1, bpm): HR difference from peak to 1 min after exercise] and chronotropic response to exercise [%chronotropic reserve (CR, %)=(peak HR-resting HR/220-age-resting HR)x100]. Left ventricular ejection fraction (LVEF, %) was also measured by radionuclide ventriculography.

RESULTS

Fatal events occurred in 24 patients (26%) during 21+/-6 months of follow-up. HRR1 was lower in non-survivors (11.4+/-6.4 vs. 20.4+/-8.1; p<0.001). All cause-mortality rate was 65% in patients with HRR1<or=12 bpm versus 11% in patients with HRR1>12 bpm (log-rank: 32.6; p<0.001). By multivariate survival analysis, HRR1 resulted as an independent predictor of mortality (chi2=19.2; odds ratio: 0.87; p<0.001) after adjustment for LVEF, VO2p, VE/VCO2 slope, CR and VO2/t-slope. In a subgroup of patients with intermediate exercise capacity (VO2p: 10-18, ml/kg/min), HRR1 was a strong predictor of mortality (chi2: 14.3; odds ratio: 0.8; p<0.001).

CONCLUSIONS

Early heart rate recovery is an independent prognostic risk indicator in CHF patients and could be used in CHF risk stratification.

The Irbesartan in Heart Failure With Preserved Systolic Function (I-PRESERVE) Trial: Rationale and Design

BACKGROUND

Although 40% to 50% of patients with chronic heart failure (HF) have relatively preserved systolic function (PSF), few trials have been conducted in this population and treatment guidelines do not include evidence-based recommendations.

METHODS AND RESULTS

The Irbesartan in Heart Failure with Preserved Systolic Function (I-PRESERVE) is enrolling 4100 subjects with HF-PSF to evaluate whether 300 mg irbesartan is superior to placebo in reducing mortality and prespecified categories of cardiovascular hospitalizations. The principal inclusion criteria are age > or =60 years, heart failure symptoms, an ejection fraction > or =45%, and either hospitalization for heart failure within 6 months or corroborative evidence of heart failure or the substrate for diastolic heart failure. Additional secondary end points include cardiovascular mortality, cause-specific mortality and morbidity, change in New York Heart Association functional class, quality of life, and N-terminal pro-BNP measurements. Follow-up will continue until 1440 patients experience a primary end point. Substudies will evaluate changes in echocardiographic measurements and serum collagen markers.

CONCLUSION

I-PRESERVE is the largest trial in this understudied area and will provide crucial information on the characteristics and course of the syndrome, as well as the efficacy of the angiotensin receptor blocker irbesartan.

Diastolic heart failure: recognition, diagnosis and management

A variety of community-based epidemiological studies have suggested that 30-50% of patients with heart failure symptoms appear to have preserved left ventricular (LV) systolic function when assessed by echocardiography or similar techniques suggesting 'diastolic heart failure' (DHF) as its cause. The prognosis of these patients is characterised by morbidity and mortality similar to, but less overt than, patients with systolic dysfunction. However, rates of readmission for symptom control are broadly similar in patients with DHF or in those with systolic impairment. Thus, there are many similarities in the portrayal of both systolic and DHF but equally; there are also many key differences. Certainly, while there are several successful therapies for patients with systolic heart failure, the management of patients with DHF is poorly defined. In this review, the gaps in current knowledge and practice, which is creating this therapeutic void will be addressed.

Comparison of mental stress-induced myocardial ischemia in coronary artery disease patients with versus without left ventricular dysfunction

To examine the susceptibility to myocardial ischemia with mental stress in patients who have coronary artery disease and normal left ventricular (LV) function versus those who have impaired LV function, we examined 58 patients who had coronary artery disease, including 22 who had normal LV function (ejection fraction >/=50%), 16 who had mild to moderate LV dysfunction (ejection fraction 30% to 50%), and 20 who had severe LV dysfunction (ejection fraction </=30%) and underwent bicycle and mental stress testing with myocardial perfusion scintigraphy on consecutive days in random order. Ischemia was assessed based on summed difference scores in regional rest versus stress myocardial perfusion and defined as a summed difference score >3. At comparable double products across the 3 groups, ischemia was induced with mental stress more frequently in patients who had severe LV dysfunction (50%) than in those who had normal LV function (9%; p <0.01). The frequency of exercise-induced ischemia was different only between those who had mild/moderate LV dysfunction and those who had normal LV function (56% vs 18%, respectively, p <0.05). The pattern of mental stress versus exercise ischemia differed between groups (p <0.02): there was a higher prevalence of mental stress ischemia versus exercise ischemia in patients who had severe LV dysfunction (p = 0.06), a marginally higher prevalence of exercise versus mental stress ischemia in those who had moderate LV dysfunction (p = 0.07), and no difference in mental stress versus exercise ischemia in those who had normal LV function. Thus, at comparable double products during mental stress and similar extent of coronary artery disease, ischemia with mental stress was induced more frequently in patients who had severe LV dysfunction than in those who had normal LV function. These data suggest that mental stress ischemia may be of particular clinical importance in patients who have coronary artery disease and LV dysfunction.

A phase II, double-blind, randomized, placebo-controlled, dose comparative study of the efficacy, tolerability, and safety of MCC-135 in subjects with chronic heart failure, NYHA class II/III (MCC-135-GO1 study): rationale and design

BACKGROUND

Chronic heart failure (CHF) can be caused either by a predominant abnormality in systolic function (systolic heart failure) or a predominant abnormality in diastolic function (diastolic heart failure). Randomized clinical trials have identified a number of pharmaceutical agents that can reduce morbidity and mortality in patients with systolic heart failure. Despite significant therapeutic advances, systolic heart failure continues to result in high rates of morbidity and mortality. In contrast to systolic heart failure, no randomized clinical trials have been performed in patients with diastolic heart failure. Common to the mechanisms causing both systolic and diastolic heart failure are abnormalities in calcium homeostasis. Mitsubishi Pharma Corporation has developed a compound (MCC-135, INN; caldaret) whose mechanism of action is proposed to be modulation of calcium homeostasis at the sarcoplasmic reticulum and cellular membrane. The purpose of this study was to test the safety, tolerability, and efficacy of MCC-135 in patients with mild to moderate heart failure.

METHODS

This was a phase II, multicenter, randomized, double-blind study of parallel group design comparing 3 oral dose regimens of MCC-135 (5 mg, 25 mg, 50 mg, twice daily) with a placebo control. The treatment period was 24 weeks. A total of 511 patients were recruited from 69 centers in the United States and Europe. One hundred and twenty-five patients were recruited in each of the 4 treatment groups. Patients in each treatment group were divided into 2 cohorts: those with an ejection fraction < or = 40%, and those with an ejection fraction >40% as determined by core laboratory analysis of echocardiographic studies.

CONCLUSION

Patient recruitment was completed in September 2002. Patient follow-up was completed by February 2003; the results will be available for release in 2004.

Diastolic heart failure: a difficult problem in the elderly

Heart failure with normal systolic function has been equated to diastolic heart failure (DHF). DHF appears to be quite common in the elderly, especially in elderly women with hypertension. Recent epidemiologic studies suggest that 30%-50% of patients with heart failure may have DHF. Morbidity for DHF is considerable and comparable to that of heart failure with left ventricular systolic dysfunction. Both groups of patients have similar rates of recurrent hospitalization and cost of care. Long-term mortality also appears to be similar in the two groups of patients. With the aging of the population, the numbers of patients with DHF will continue to rise and are likely to contribute significantly to the burden of disease caused by heart failure. Unfortunately, as yet, no reliable definition has been found for DHF. Currently the diagnosis of DHF is often made by exclusion, and treatment is empirical and unsatisfactory because of the lack of large-scale, randomized, controlled trials in this area; however, several large and other smaller trials are currently in progress that will hopefully provide some answers.

Diastolic Dysfunction

Heart failure is a leading cause of hospital admissions in North America. Approximately half of patients with symptoms of heart failure have normal or minimally impaired systolic function and are therefore diagnosed, by exclusion, with diastolic dysfunction. The therapy of diastolic dysfunction to date is largely unsatisfactory. There have been few outcome-based clinical trials to guide clinicians, and most treatments have been empirically derived from the data from systolic heart failure studies. In general, acute management consists of central volume reduction with loop diuretics and long-acting nitrates. In some cases improvement in left ventricular filling can be achieved by reducing heart rate, usually with either beta blockers or calcium channel blockers. The role of digoxin is unclear and it should be used with caution. Theoretically, it has the capacity to further impair ventricular function, but one of the few trials in diastolic heart failure suggested that it improves symptoms and reduces hospitalization. Renin-angiotensin system blockade is a very attractive therapeutic avenue; angiotensin-converting enzyme inhibitors and angiotensin receptor blockers effectively reduce afterload, induce regression of left ventricular hypertrophy in excess of their blood pressure-lowering effect, and confer survival benefits to patients at high risk for cardiovascular death. Although the results of a recent trial using an angiotensin receptor blocker in patients with primarily diastolic heart failure were unimpressive, renin-angiotensin system blockade should still be considered because of its aforementioned benefits. The long-term management of these patients includes a careful assessment for and treatment of myocardial ischemia, treatment of hypertension, and reduction in left ventricular hypertrophy. For the treatment of ischemia, long-acting nitrates and calcium channel blockers may be particularly useful. The results of new trials in this area are expected soon, and hopefully therapy that directly targets the pathophysiologic pathways of this important disease is on the horizon.

Effects of spironolactone and metoprolol on QT dispersion in heart failure

The effects of spironolactone or metoprolol added to a conventional treatment protocol on QT dispersion, which is accepted as a sudden cardiac death predictor, were evaluated in heart failure patients.? A total of 105 New York Heart Association class III patients were included in this study. The conventional treatment protocol was standardized by giving ramipril, furosemide, and digoxin to all patients for 3 weeks at the same doses. At the end of this period, the patients were divided into three groups. Conventional treatment was continued in group 1, 25 mg spironolactone was added in group 2, and 12.5 mg metoprolol was added in group 3. Patients were followed for 12 weeks and clinical and laboratory tests were conducted at 3 week intervals. No significant change in corrected QT dispersion was observed in group 1 at the end of 12 weeks (corrected QT dispersion: 80 +/- 2 msc to 79 +/- 2 msc, P: 0.22). However, corrected QT dispersion in group 2 was reduced by 32.5% (83 +/- 2 msc to 56 +/- 1 msc; P: 0.01). A 32.9% reduction in corrected QT dispersion (79 +/- 2 msc to 53 +/- 2 msc; P: 0.01) was observed in group 3. In conclusion, the addition of spironolactone or metoprolol to a conventional treatment in heart failure patients resulted in improved clinical conditions and the significant decrease in sudden death predictors corrected QT dispersion. The effects of spironolactone and metoprolol on corrected QT dispersion were similar.

A visual approach for the accurate determination of echocardiographic left ventricular ejection fraction by medical students

BACKGROUND

Previously published reports show that there is significant intraobserver, interobserver, and interinstitutional variability in the determination of left ventricular (LV) ejection fraction (EF) by echocardiography. With the increased deployment of echocardiography (eg, handheld devices), there exists a need for developing a simple, intuitive approach for evaluating LVEF that allows a wider range of physicians to accurately and rapidly determine LVEF.

OBJECTIVE

We sought to create a system for assessing LVEF that relies on recognition and matching of patterns, rather than on mathematic calculations and geometric assumptions.

METHODS

A library of videoclips of cardiac function was compiled from 54 patients who spanned the spectrum of LVEF. LVEFs were calculated for these patients using standard echocardiographic methods, with further validation of a subsample using cardiac magnetic resonance imaging measurement of LVEF. The library of images was used to create a software tool for assessing LVEF on the basis of a "template-matching" approach. The software tool was then tested on medical students (N=13) to determine whether it enabled relatively untrained individuals to make accurate LVEF estimates.

RESULTS

Using a template-matching approach for interpretation of echocardiograms, medical students were able to accurately estimate LVEF after only a limited introduction to echocardiography. Their LVEF estimates showed good correlation and agreement with gold standard (r = 0.88, standard square of the estimate = 6.0, limits of agreement = +12.0%, -15.6%).

CONCLUSIONS

A new visual approach for assessing cardiac function using template matching can accurately estimate LVEF. With minimal training, medical students can make LVEF estimates that correlate well with gold standard. The application of this new approach includes allowing for the interpretation of LVEF from echocardiograms to be performed by a broader spectrum of physicians.

Prognosis of congestive heart failure in patients with normal versus reduced ejection fractions: results from a cohort of 2,258 hospitalized patients

BACKGROUND

Patients with congestive heart failure have an annual mortality of 10% to 20% depending on disease severity. Though one third of these patients have normal left ventricular (LV) ejection fraction (EF), their natural history is poorly defined. Small population-based studies have suggested a more benign prognosis for patients with preserved LVEF. However, prognosis in hospitalized patients, who form a higher risk group, is not known.

METHODS

We investigated the survival patterns of 2,258 patients with a primary hospital discharge diagnosis of congestive heart failure between 1990 and 1999. Survival was analyzed and patients with normal and reduced LVEF were compared.

RESULTS

Their age was 71 +/- 11 years, and 97% were men. There were 1,535 deaths over a mean follow up of 786 days. Of these, 963 (43%) patients had a normal LVEF (>/=55%). Patients with normal LVEF were of the same age as those with reduced LVEF, but had a lower prevalence of atrial fibrillation (20 versus 26%, P =.03), left bundle branch block (2 versus 12%, P <.0001), significant mitral regurgitation (5 versus 31%, P <.0001) and electrocardiographic evidence of myocardial infarction (38 versus 60%, P <.0001). Despite lesser comorbidities, they had a higher mortality hazard, with a 5-year survival of 22% compared with 28% for those with systolic heart failure (P =.007). Proportional hazards model showed presence of normal EF as a categoric variable to be an independent predictor of mortality in those with heart failure after correcting for age and rhythm.

CONCLUSIONS

Prognosis of hospitalized patients with congestive heart failure and normal LVEF is worse than those with reduced EF despite lesser comorbidities. Studies addressing optimal management of these patients are warranted.

The problem of decompensated heart failure: nomenclature, classification, and risk stratification

Despite its high prevalence and significant rates of associated morbidity and mortality, the syndrome of decompensated heart failure remains poorly defined and vastly understudied. Few high-quality epidemiologic studies, randomized controlled trials, or published guidelines are available to guide the management of this complex disease. In addition, there is no consensus definition of the clinical problem that it presents, no agreed upon nomenclature to describe its clinical features, and no recognized classification scheme for its patient population; all of which has contributed to the lack of therapeutic development in this critical arena of cardiovascular disease. This review outlines the scope of the problem and proposes a system of nomenclature and classification sufficiently simple for general acceptance among clinicians while still encompassing the heterogeneity of the patient population. It also defines the current understanding of strategies for risk stratification in the setting of decompensated heart failure.

The relevance of subgroup-specific treatment effects: the Studies Of Left Ventricular Dysfunction (SOLVD) revisited

BACKGROUND

The overall effect sizes estimated from randomized clinical trials may not apply similarly to all patients. Univariate subgroup analyses are often used to help determine the generalizability of a trial's results, but may themselves be misleading. We reanalyzed the Studies of Left Ventricular Dysfunction (SOLVD) to determine whether the treatment effect depended on the patients' baseline prognosis, defined on the basis of multiple clinical variables.

METHODS

The SOLVD prevention (4228 patients) and the SOLVD treatment (2569 patients) trials were randomized, double-blind trials that studied the effect of enalapril in patients with reduced left-ventricular function or congestive heart failure. We combined both SOLVD populations and compared the results of a univariate analysis to a multivariate approach in which 3 patient subgroups were defined according to baseline risks for the combined end point of death or hospitalization for heart failure.

RESULTS

Enalapril treatment resulted in 24% fewer events. The strongest predictors of an event were ejection fraction, New York Heart Association classification and age, antiplatelet agents, history of diabetes mellitus, treatment with digoxin or diuretics, and race. Only ejection fraction produced a significant treatment interaction (P =.004). Consistent with the original SOLVD reports, this interaction was also demonstrable when ejection fraction was scaled into tertiles and examined on its own (P =.012). However, there was no interaction present when patients were divided into tertiles of multifactorial baseline risk.

CONCLUSIONS

We confirmed the treatment effect of enalapril, the impact of left-ventricular systolic function, and the negative prognostic importance of diabetes mellitus in this population. Although ejection fraction led to a subgroup-treatment interaction in the main SOLVD publications, a multifactorial approach to prognostic grouping abolished the interaction. These findings highlight the limitations of univariate subgroup analyses and illustrate that multivariate risk group analysis may be a complementary method for assessing the generalizability of the overall treatment effects observed in randomized trials.

Is heart failure with preserved systolic function an overlooked enigma?

Heart failure with preserved systolic function, or diastolic heart failure, represents the neglected other half of the pandemic of heart failure. Unlike previously held beliefs, diastolic heart failure carries with it the same connotation of morbidity and mortality as systolic heart failure, particularly in the elderly. Due to lack of standards in application of the diagnosis of diastolic heart failure, studies are difficult to interpret due to heterogeneity in the clinical criteria applied to the patient enrollment. It is imperative that preventive efforts be implemented in high-risk groups, and screening measures with newer biomarkers be considered for identifying underlying structural heart disease in order to employ preventive therapy early in the course of illness. No evidence-based therapeutic strategy to reduce morbidity and mortality has been established, even after the diagnosis of diastolic heart failure is manifest. Current therapy targets lusitropic abnormalities in the realm of impaired relaxation, abnormal diastolic compliance, avoidance of tachycardia, and restoration of atrial booster pump function. Outcomes-based placebo-controlled clinical trials are currently underway to define appropriate therapeutic strategies in diastolic heart failure.

Left bundle-branch block is associated with increased 1-year sudden and total mortality rate in 5517 outpatients with congestive heart failure: a report from the Italian network on congestive heart failure

BACKGROUND

A deleterious effect of complete left bundle-branch block (LBBB) on left ventricular function has been established. Nevertheless, the independent effect of a widened QRS on mortality rate in congestive heart failure (CHF) is still controversial. Therefore, we carried out this analysis to determine whether LBBB is an independent predictor of mortality in CHF.

METHODS AND RESULTS

We analyzed the large Italian Network on CHF Registry of unselected outpatients with CHF of different causes. The registry was established by the Italian Association of Hospital Cardiologists in 1995. Complete 1-year follow-up data were available for 5517 patients. The main underlying cardiac diagnosis was ischemic heart disease in 2512 patients (45.6%), dilated cardiomyopathy in 1988 patients (36.0%), and hypertensive heart disease in 714 patients (12.9%). Other causes were recorded in the remaining 303 cases (5.5%). LBBB was present in 1391 patients (25.2%) and was associated with an increased 1-year mortality rate from any cause (hazard ratio, 1.70; 95% confidence interval, 1.41 to 2.05) and sudden death (hazard ratio, 1.58; 95% confidence interval, 1.21 to 2.06). Multivariate analysis showed that such an increased risk was still significant after adjusting for age, underlying cardiac disease, indicators of CHF severity, and prescription of angiotensin-converting enzyme inhibitors and beta-blockers.

CONCLUSION

LBBB is an unfavorable prognostic marker in patients with CHF. The negative effect is independent of age, CHF severity, and drug prescriptions. These data may support the rationale of randomized trials to verify the effects on mortality rate of ventricular resynchronization with multisite cardiac pacing in patients with CHF and LBBB.

Diastolic heart failure: neglected or misdiagnosed?

Recent epidemiological studies suggest that 30% to 50% of patients with heart failure (HF) have preserved left ventricular (LV) systolic function. These patients, often presumed to have diastolic heart failure (DHF), appear to have lower short-term but similar long-term mortality when compared to patients with HF and LV systolic dysfunction. Rates of recurrent hospitalization and costs of care appear similar in the two groups of patients. Therefore, DHF may contribute significantly to the burden of disease caused by HF. Exertional breathlessness, the principal symptom of HF, has many causes, including obesity, pulmonary disease and myocardial ischemia. A diagnosis of DHF by exclusion, based on symptoms in the absence of important LV systolic dysfunction or major valve disease, is unsatisfactory. Unfortunately, as yet, no reliable definition with which to make a positive diagnosis of DHF has been agreed on, frequently rendering this diagnosis uncertain. Echocardiography has several limitations, whereas hemodynamic confirmation of DHF by cardiac catheterization is potentially complex and not practically feasible for many patients. Treatment of DHF remains empirical and unsatisfactory because of the lack of large-scale randomized controlled trials in this area. Currently, three large outcome studies on DHF are in progress along with other smaller trials. These should start to provide some of the answers we need to diagnose and effectively treat DHF.

Clinical features and outcomes of elderly outpatients with heart failure followed up in hospital cardiology units: data from a large nationwide cardiology database (IN-CHF Registry)

BACKGROUND

Congestive heart failure (HF) represents a major public health problem with an age-related increasing prevalence. Despite the high mortality and morbidity in elderly patients with HF, limited clinical and prognostic data are available for development of appropriate prevention and treatment strategies.

METHODS

A cohort of 3327 outpatients consecutively enrolled in the Registry of Italian Network on Congestive Heart Failure by 133 cardiology centers was studied. Univariate and multivariate analyses were performed to compare patients <70 and > or =70 years old and to evaluate associations between clinical variables and the 1-year mortality rate and hospitalizations.

RESULTS

With respect to the 2294 patients <70 years old, the 1033 (31%) elderly patients were significantly more likely to be female, to be in New York Heart Association (NYHA) class III-IV, and to have preserved left ventricular systolic function (ejection fraction >40%), an ischemic/valvular etiology, and atrial fibrillation/flutter. Elderly patients received angiotensin-converting enzyme inhibitors, beta-blockers, and anticoagulants less frequently than younger patients did. The 1-year mortality rate was significantly higher in patients > or =70 years old (22% vs 13.7%, P <.001). Age was an independent predictor of 1-year mortality, increasing 2.8% by each year of age. Independent predictors of 1-year mortality in elderly patients were (1) > or =1 hospital admission in the previous year (relative risk [RR] 2.09, 95% CI 1.51-2.87), (2) systolic blood pressure (RR 0.98, 95% CI 0.97-0.99), (3) NYHA class III-IV (RR 1.57, 95% CI 1.20-2.07), and (4) age (RR 1.028, 95% CI 1.001-1.056).

CONCLUSIONS

Our study confirms that elderly patients (1) are seen in a more advanced stage of HF, (2) are less likely to receive evidence-based treatments, (3) show more frequently preserved systolic function, and (4) have a worse prognosis. Consequently, there is a need to develop more effective and targeted management strategies for this escalating health problem.

Effect of increased body mass index on accuracy of two-dimensional echocardiography for measurement of left ventricular volume, ejection fraction, and mass

We used 2- and 3-dimensional echocardiography to determine left ventricular volume, mass, and ejection fraction in overweight (body mass index [BMI] > or = 25 kg/m2), obese (BMI > or = 30 kg/m2), and control (BMI < 25 kg/m2) subjects. Compared with corresponding magnetic resonance imaging measurements, 3-dimensional echocardiography is more accurate than 2-dimensional echocardiography in all patients, but particularly in overweight and obese subjects.

Clinical characteristics and long-term outcomes of patients with heart failure and preserved systolic function

Although the syndrome of heart failure with preserved systolic function may occur in up to 40% of all heart failure patients, the clinical, angiographic characteristics, and long-term outcomes of these patients are poorly understood. We prospectively evaluated 2,498 consecutive patients with New York Heart Association class II to IV symptoms and ejection fractions of >40%, who underwent cardiac catheterization between January 1984 and December 1996 at Duke University Medical Center. The median age for the entire cohort was 63 years; 25% of the population was >71 years old. In addition, 55% of the patients were women, 65% had ischemic heart disease, 28% had a history of diabetes, and 62% had a history of hypertension. The median ejection fraction was 58%. One third of the patients had multivessel disease by coronary angiography. The overall 5-year mortality of the total population was 28%. The independent predictors of mortality (p <0.05) using a multivariable Cox proportional hazard model were age, class IV symptoms, ejection fraction, coronary artery disease index, diabetes, peripheral vascular disease, and minority ethnic group. Heart failure with preserved systolic function is characterized by unique clinical and angiographic characteristics associated with a 5-year mortality rate of 28%. Furthermore, several clinical and angiographic characteristics are predictive of long-term survival.

Bradykinin degradation and relation to myocyte contractility

BACKGROUND

Past studies have demonstrated that exogenous bradykinin (BK) causes vasodilation and increases coronary blood flow, effects that may be beneficial in the setting of cardiac disease states. An important pathway for BK degradation is through angiotensin-converting enzyme (ACE), which results in the formation of a degradative peptide, BK((1-7)). The goal of this study was to examine the effects of BK, BK((1-7)), and the potential modulation of BK by ACE inhibition on myocyte contractility.

METHODS AND RESULTS

Contractile function was examined in isolated adult porcine (n = 15) left ventricular (LV) myocyte preparations in the presence or absence of BK (10(-8) mol/L), BK((1-7)) (10(-8) mol/L), and with pretreatment by ACE inhibition (benazaprilat). Myocyte velocity of shortening fell by over 15% in the presence of BK and by 8% with BK((1-7)) (P <.05 vs basal). ACE inhibition blunted the negative effect of BK on myocyte velocity of shortening by over 60% (P <.05). Furthermore, robust ACE activity coupled with significant BK degradation was demonstrated in LV-isolated myocyte preparations, and BK proteolysis was influenced by ACE inhibition.

CONCLUSION

These results suggest that BK has a direct effect on LV myocyte contractility, and that this effect may be mediated by proteolysis of BK at the level of the LV myocyte sarcolemma.

Accuracy of three-dimensional echocardiography with unrestricted selection of imaging planes for measurement of left ventricular volumes and ejection fraction

BACKGROUND

Accurate, reproducible, noninvasive determination of left ventricular (LV) volumes and ejection fraction (EF) is important for clinical assessment, risk stratification, selection of therapy, and serial monitoring of patients with cardiovascular disease. Three-dimensional echocardiography (3DE) approaches have demonstrated significantly greater accuracy than current clinical 2DE, but the clinical utility of 3DE has been limited because of the need for substantial modifications to scanning technique (eg, all image acquisition from a single acoustic window) or cumbersome additional hardware. We describe a novel 3DE system without these limitations and its application to patients.

METHODS AND RESULTS

Twenty-five patients were examined by 3DE, 2DE, and magnetic resonance imaging (MRI). The 3DE system used a magnetic scanhead tracking device, and volumes were computed with a novel deformable shell model. End-diastolic volumes and EF by MRI ranged from 96 to 375 mL and 18% to 73%, respectively. There was excellent correlation, without statistically significant differences, between MRI and 3DE for end-systolic volume (ESV) (r(2) = 0.99) and end-diastolic volume (EDV) (r(2) = 0.98), ventricular stroke volume (SV) (r(2) = 0.93), and EF (r(2) = 0.97), with standard error estimates less than 10 mL for volumes and 3% for EF. Conventional 2DE consistently underestimated volumes (EDV, P <.01; ESV, P <.01; SV, P <.05); correlations with MRI were r(2) = 0.91 for ESV, r(2) = 0.88 for EDV, r(2) = 0.62 for SV, and r(2) = 0.72 for EF. Standard error estimates ranged from 16 to 20 mL for ventricular volumes and 9% for EF. Interobserver variability was reduced 3-fold with use of 3DE.

CONCLUSIONS

The novel 3DE system allows unrestricted selection and combination of acoustic windows in a single examination, improves accuracy of estimates of LV volumes and EF 3-fold compared with 2DE, and is practical for routine clinical assessment of LV size and function in patients with a wide range of cardiac pathology.

Metoprolol: a review of its use in chronic heart failure

Metoprolol, a relatively selective beta1-blocker, is devoid of intrinsic sympathomimetic activity and possesses weak membrane stabilising activity. The drug has an established role in the management of essential hypertension and angina pectoris, and more recently, in patients with chronic heart failure. The effects of metoprolol controlled-release/extended-release (CR/XL) in patients with stable, predominantly mild to moderate (NYHA functional class II to III) chronic heart failure have been evaluated in the large Metoprolol CR/XL Randomised Intervention Trial in Congestive Heart Failure (MERIT-HF) trial and the much smaller Randomized Evaluation of Strategies for Left Ventricular Dysfunction (RESOLVD) pilot study. Treatment with metoprolol CR/XL was initiated at a low dosage of 12.5 to 25 mg once daily and gradually increased at 2-weekly intervals until the target dosage (200 mg once daily) or maximal tolerated dosage had been attained in patients receiving standard therapy for heart failure. At 12 months, metoprolol CR/XL was associated with a 34% reduction in relative risk of all-cause mortality in patients with chronic heart failure due to ischaemic or dilated cardiomyopathy in the MERIT-HF trial. The incidence of sudden death and death due to progressive heart failure were both significantly decreased with metoprolol CR/XL. Similarly, a trend towards decreased mortality in the metoprolol CR/XL group compared with placebo was observed in the RESOLVD trial. Data from small numbers of patients with severe (NYHA functional class IV) heart failure indicate that metoprolol CR/XL is effective in this subset of patients. However, no firm conclusions can yet be drawn. Improvement from baseline values in NYHA functional class, exercise capacity and some measures of quality of life with metoprolol CR/XL or immediate-release metoprolol were significantly greater than those with placebo. The drug is well tolerated when treatment is initiated in low dosages and gradually increased at intervals of 1 to 2 weeks.

CONCLUSIONS

Metoprolol CR/XL effectively decreases mortality and improves clinical status in patients with stable mild to moderate (NYHA functional class II or III) chronic heart failure due to left ventricular systolic dysfunction, and the drug is effective in patients with ischaemic or dilated cardiomyopathy. Although limited data indicate that metoprolol CR/XL is effective in patients with severe (NYHA functional class IV) chronic heart failure, more data are needed to confirm these findings. Treatment with metoprolol CR/XL significantly reduced the incidence of sudden death and death due to progressive heart failure.

Cardiac protection: evolving role of angiotensin receptor blockers

Congestive heart failure (HF) is a common and serious public health problem affecting approximately 5 million Americans. Recent treatment strategies have focused on attenuating the effects of angiotensin (Ang) II, which include vasoconstriction, sodium retention, sympathetic activation, and cell growth. Angiotensin-converting enzyme (ACE) inhibitors, which primarily block the systemic formation of Ang II, reduce HF-related morbidity and mortality rates. However, ACE inhibitors may not suppress Ang II activity over their entire dosing interval and, with long-term therapy, Ang II levels tend to return to normal. It is now known that Ang II can be formed independent of ACE by the action of enzymes such as chymase in local tissues, including the heart. Despite the established benefits of ACE inhibitor treatment, HF-related morbidity and mortality rates continue to increase because the aging of the population is placing more patients at risk of HF. By acting at the receptor level, Ang II receptor blockers (ARBs) should, at least theoretically, provide more "complete" Ang II blockade. Early evidence suggests that ARBs induce hemodynamic improvement in patients with HF and may reduce mortality rates. Because ACE inhibitors and ARBs block Ang II through fundamentally different mechanisms, the combination may provide additive therapeutic effects in patients with HF. Results from a pilot study suggest that the combination of an ACE inhibitor and valsartan results in a more thorough inhibition of Ang II and an additive improvement in cardiac hemodynamics. Clinical trials now in progress will elucidate the effects of combined ACE inhibitor and ARB therapy on HF-related morbidity and mortality rates.

The relationship between QT intervals and mortality in ambulant patients with chronic heart failure. The united kingdom heart failure evaluation and assessment of risk trial (UK-HEART)

AIMS

Mortality in patients with heart failure remains high and is difficult to predict. QT interval parameters on a 12-lead ECG have been shown to predict arrhythmic events in patients with a variety of myocardial diseases. There is some, but not consistent, evidence that QT interval parameters may act as predictors of mortality, in particular sudden death, in patients with heart failure. In an adequately powered prospective study we have studied QT interval parameters in patients with stable chronic heart failure in order to determine whether they are predictive of all-cause mortality or mode of death.

METHODS AND RESULTS

Five hundred and fifty-four ambulant outpatients with chronic heart failure were recruited. A 12-lead ECG, chest radiograph, echocardiogram, 24 h ambulatory electrocardiogram and serum for biochemical analysis were obtained at baseline. Patients were followed for 471+/-168 days. QT intervals were measured in all leads blinded to patient's characteristics and outcome, were corrected for heart rate, and the maximum QT intervals, and QT dispersion (range of QT intervals) were determined. The same parameters were determined for JT intervals. The primary end-point was all-cause mortality, secondary end-points were sudden cardiac death and death due to progressive heart failure. Multivariate analysis with the Cox's proportional hazards model was used to determine which variables were independently related to outcome. Four hundred and ninety-five patients had analysable ECGs at study entry and of these 71 died during follow-up. The heart rate corrected QT dispersion and maximum QT interval were significant univariate predictors of all-cause mortality (P=0.026 and <0.0001 respectively), and also of sudden death and progressive heart failure death, but were not related to outcome in the multivariate analysis. The independent predictors of all-cause mortality were cardiothoracic ratio (P=0.0003), creatinine (P=0.0009), heart rate (P=0.007), echocardiographically derived left ventricular end-diastolic dimension (P=0.007) and ventricular couplets on 24 h electrocardiographic monitoring (P=0.015).

CONCLUSION

In an adequately powered prospective study none of the QT or JT parameters were shown to be independent predictors of outcome in patients with mild to moderate congestive heart failure. These variables do not therefore add to the prognostic information which can be gained from simple radiographic, biochemical, echocardiographic and Holter data in this group of patients.

Perindopril for elderly people with chronic heart failure: the PEP-CHF study. The PEP investigators

BACKGROUND

The prevalence of chronic heart failure (CHF) rises with increasing age, from < 1% in those below 65 years of age to > 5% in those over 65 years of age and is a major cause of morbidity and mortality in older people. Recent European guidelines point to a major deficiency in our knowledge of how to treat diastolic chronic heart failure, and a lack of information on treatment for heart failure in the elderly in general.

AIMS

The aims of this trial are to assess the potential benefits of the ACE inhibitor perindopril to treat chronic heart failure in elderly people, in the absence of any major left ventricular systolic dysfunction.

SUBJECTS

One thousand people over the age of 70 years will be recruited into this study. Evidence of chronic heart failure will be confirmed by clinical criteria and echocardiography.

METHODS

Once a diagnosis of chronic heart failure has been confirmed, the patient will receive either perindopril or placebo in addition to their usual treatment. Death, and unplanned heart failure related hospitalisations, are the primary outcomes. Quality of life, as measured by the Guyatt questionnaire will be assessed at the beginning of the study and at 1 year. Sub-studies of this trial include a 6-min walking test and more detailed evaluation of ventricular function (as assessed by echocardiography). Both parameters will be measured at 8 weeks and 1 year, and analysed against baseline data. Cognitive function in this group of patients will also be evaluated at baseline and 1 year. This trial is due to report in the year 2001.

Prospective study of heart rate variability and mortality in chronic heart failure: results of the United Kingdom heart failure evaluation and assessment of risk trial (UK-heart)

BACKGROUND

Patients with chronic heart failure (CHF) have a continuing high mortality. Autonomic dysfunction may play an important role in the pathophysiology of cardiac death in CHF. UK-HEART examined the value of heart rate variability (HRV) measures as independent predictors of death in CHF.

METHODS AND RESULTS

In a prospective study powered for mortality, we recruited 433 outpatients 62+/-9.6 years old with CHF (NYHA functional class I to III; mean ejection fraction, 0.41+/-0.17). Time-domain HRV indices and conventional prognostic indicators were related to death by multivariate analysis. During 482+/-161 days of follow-up, cardiothoracic ratio, SDNN, left ventricular end-systolic diameter, and serum sodium were significant predictors of all-cause mortality. The risk ratio for a 41.2-ms decrease in SDNN was 1.62 (95% CI, 1.16 to 2.44). The annual mortality rate for the study population in SDNN subgroups was 5.5% for >100 ms, 12.7% for 50 to 100 ms, and 51.4% for <50 ms. SDNN, creatinine, and serum sodium were related to progressive heart failure death. Cardiothoracic ratio, left ventricular end-diastolic diameter, the presence of nonsustained ventricular tachycardia, and serum potassium were related to sudden cardiac death. A reduction in SDNN was the most powerful predictor of the risk of death due to progressive heart failure.

CONCLUSIONS

CHF is associated with autonomic dysfunction, which can be quantified by measuring HRV. A reduction in SDNN identifies patients at high risk of death and is a better predictor of death due to progressive heart failure than other conventional clinical measurements. High-risk subgroups identified by this measurement are candidates for additional therapy after prescription of an ACE inhibitor.

Clinical course of Chagas' heart disease: a comparison with dilated cardiomyopathy

This investigation was carried out to compare the clinical course of patients with chronic Chagas' heart disease with that of patients with dilated cardiomyopathy. A total of 125 patients (75 chagasic and 50 nonchagasic) prospectively followed up at the Cardiomyopathy clinic of Santa Casa Hospital from January 1990 to June 1993 entered the study. Patients underwent clinical history, physical examination, serological tests, resting electrocardiogram, chest X-ray and two-dimensional echocardiography. In nonchagasic patients, hypertensive cardiomyopathy was found in 17 of 50 (34%) patients, idiopathic dilated cardiomyopathy in 16 (32%), the association of hypertension and coronary artery disease in 12 (24%) and ischemic cardiomyopathy in two (4%). Twenty-one (23%) chagasic and three (6%) nonchagasic patients died during the study period (P = 0.02). Sudden cardiac death occurred in eight (38%) chagasic patients, pump failure death was detected in 10 (47%) and the mode of death could not be determined in three (14%) patients with chronic Chagas' heart disease. Thus, patients with chronic Chagas' heart disease have a clinical course worse than that of patients with nonchagasic dilated cardiomyopathy. This fact may be ascribed to the electrocardiographic and morphological peculiarities usually found in chronic Chagas' heart disease.

Course and prognosis in patients > or = 70 years of age with congestive heart failure and normal versus abnormal left ventricular ejection fraction

In this study of 501 patients aged > or =70 years hospitalized with congestive heart failure, 34.1% had normal left ventricular systolic function. Reduced left ventricular ejection fraction was an independent predictor of an adverse prognosis at 3 months but not at 1 year.