Systolic and diastolic heart failure in the community

CONTEXT

The heart failure (HF) syndrome is heterogeneous. While it can be defined by ejection fraction (EF) and diastolic function, data on the characteristics of HF in the community are scarce, as most studies are retrospective, hospital-based, and rely on clinically indicated tests. Further, diastolic function is seldom systematically assessed based on standardized techniques.

OBJECTIVE

To prospectively measure EF, diastolic function, and brain natriuretic peptide (BNP) in community residents with HF.

MAIN OUTCOME MEASURES

Echocardiographic measures of EF and diastolic function, measurement of blood levels of BNP, and 6-month mortality.

DESIGN, SETTING, AND PARTICIPANTS

Olmsted County residents with incident or prevalent HF (inpatients or outpatients) between September 10, 2003, and October 27, 2005, were prospectively recruited to undergo assessment of EF and diastolic function by echocardiography and measurement of BNP.

RESULTS

A total of 556 study participants underwent echocardiography at HF diagnosis. Preserved EF (> or =50%) was present in 308 (55%) and was associated with older age, female sex, and no history of myocardial infarction (all P<.001). Isolated diastolic dysfunction (diastolic dysfunction with preserved EF) was present in 242 (44%) patients. For patients with reduced EF, moderate or severe diastolic dysfunction was more common than when EF was preserved (odds ratio, 1.67; 95% confidence interval [CI], 1.11-2.51; P = .01). Both low EF and diastolic dysfunction were independently related to higher levels of BNP. At 6 months, mortality was 16% for both preserved and reduced EF (age- and sex-adjusted hazard ratio, 0.85; 95% CI, 0.61-1.19; P = .33 for preserved vs reduced EF).

CONCLUSIONS

In the community, more than half of patients with HF have preserved EF, and isolated diastolic dysfunction is present in more than 40% of cases. Ejection fraction and diastolic dysfunction are independently related to higher levels of BNP. Heart failure with preserved EF is associated with a high mortality rate, comparable to that of patients with reduced EF.

Pathophysiologically relevant concentrations of tumor necrosis factor-alpha promote progressive left ventricular dysfunction and remodeling in rats

BACKGROUND

Although patients with heart failure express elevated circulating levels of tumor necrosis factor-alpha (TNF-alpha) in their peripheral circulation, the structural and functional effects of circulating levels of pathophysiologically relevant concentrations of TNF-alpha on the heart are not known.

METHODS AND RESULTS

Osmotic infusion pumps containing either diluent or TNF-alpha were implanted into the peritoneal cavity of rats. The rate of TNF-alpha infusion was titrated to obtain systemic levels of biologically active TNF-alpha comparable to those reported in patients with heart failure (approximately 80 to 100 U/mL), and the animals were examined serially for 15 days. Two-dimensional echocardiography was used to assess changes in left ventricular (LV) structure (remodeling) and LV function. Video edge detection was used to assess isolated cell mechanics, and standard histological techniques were used to assess changes in the volume composition of LV cardiac myocytes and the extracellular matrix. The reversibility of cytokine-induced effects was determined either by removal of the osmotic infusion pumps on day 15 or by treatment of the animals with a soluble TNF-alpha antagonist (TNFR:Fc). The results of this study show that a continuous infusion of TNF-alpha led to a time-dependent depression in LV function, cardiac myocyte shortening, and LV dilation that were at least partially reversible by removal of the osmotic infusion pumps or treatment of the animals with TNFR:Fc.

CONCLUSIONS

These studies suggest that pathophysiologically relevant concentrations of TNF-alpha are sufficient to mimic certain aspects of the phenotype observed in experimental and clinical models of heart failure.

Left Ventricular Reverse Remodeling but Not Clinical Improvement Predicts Long-Term Survival After Cardiac Resynchronization Therapy

BACKGROUND

In patients with severe heart failure and dilated cardiomyopathy, cardiac resynchronization therapy (CRT) improves left ventricular (LV) systolic function associated with LV reverse remodeling and favorable 1-year survival. However, it is unknown whether LV reverse remodeling translates into a better long-term prognosis and what extent of reverse remodeling is clinically relevant, which were investigated in this study.

METHODS AND RESULTS

Patients (n=141) with advanced heart failure (mean+/-SD age, 64+/-11 years; 73% men) who received CRT were followed up for a mean (+/-SD) of 695+/-491 days. The extent of reduction in LV end-systolic volume (LVESV) at 3 to 6 months relative to baseline was examined for its predictive value on long-term clinical outcome. The cutoff value for LV reverse remodeling in predicting mortality was derived from the receiver operating characteristic curve. Then the relation between potential predictors of mortality and heart failure hospitalizations were compared by Kaplan-Meier survival analysis, followed by Cox regression analysis. There were 22 (15.6%) deaths, mostly due to heart failure or sudden cardiac death. The receiver operating characteristic curve found that a reduction in LVESV of > or =9.5% had a sensitivity of 70% and specificity of 70% in predicting all-cause mortality and of 87% and 69%, respectively, for cardiovascular mortality. With this cutoff value, there were 87 (61.7%) responders to reverse remodeling. In Kaplan-Meier survival analysis, responders had significantly lower all-cause morality (6.9% versus 30.6%, log-rank chi2=13.26, P=0.0003), cardiovascular mortality (2.3% versus 24.1%, log-rank chi2=17.1, P<0.0001), and heart failure events (11.5% versus 33.3%, log-rank chi2=8.71, P=0.0032) than nonresponders. In the Cox regression analysis model, the change in LVESV was the single most important predictor of all-cause (beta=1.048, 95% confidence interval=1.019 to 1.078, P=0.001) and cardiovascular (beta=1.072, 95% confidence interval=1.033 to 1.112, P<0.001) mortality. Clinical parameters were unable to predict any outcome event.

CONCLUSIONS

A reduction in LVESV of 10% signifies clinically relevant reverse remodeling, which is a strong predictor of lower long-term mortality and heart failure events. This study suggests that assessing volumetric changes after an intervention in patients with heart failure provides information predictive of natural history outcomes.

Tissue Doppler imaging is superior to strain rate imaging and postsystolic shortening on the prediction of reverse remodeling in both ischemic and nonischemic heart failure after cardiac resynchronization therapy

BACKGROUND

A number of noninvasive techniques have been used to predict the effectiveness of cardiac resynchronization therapy (CRT) in heart failure patients, in particular left ventricular (LV) reverse remodeling. This study compared the relative predictive values of tissue Doppler imaging (TDI) and strain-rate imaging (SRI) parameters for LV reverse remodeling in patients who received CRT and examined for potential differences in ischemic (n=22) and nonischemic (n=32) heart failure.

METHODS AND RESULTS

TDI and SRI were performed at baseline and 3-month follow-up. Eighteen parameters of intraventricular and interventricular asynchrony based on the time to peak myocardial contraction (Ts) and time to peak strain rate (Tsr) were compared, along with postsystolic shortening (PSS). Reverse remodeling with reduction of LV end-diastolic and end-systolic volumes and gain in ejection fraction (all P<0.001) was observed in the whole study population. The standard deviation of Ts of 12 LV segments (Ts-SD) is the most powerful predictor of reverse remodeling in both the ischemic (r=-0.65, P<0.001) and nonischemic (r=-0.79, P<0.001) groups. The PSS of 12 LV segments was a good predictor only for the nonischemic (r=-0.64, P<0.001) but not the ischemic (r=0.32, P=NS) group. However, parameters of SRI and interventricular asynchrony failed to predict reverse remodeling. By multiple regression analysis, independent parameters included Ts-SD in both groups (P<0.005) and PSS of 12 LV segments in the nonischemic group (P=0.03). The area of the receiver operating characteristic curve was largest for Ts-SD (0.94; CI=0.88 to 1.00).

CONCLUSIONS

Ts-SD is the most powerful predictor of LV reverse remodeling and was consistently useful for ischemic and nonischemic heart failure. However, PSS is useful only for nonischemic pathogenesis, whereas the role of SRI parameters was not supported by the present study.

Cardiac resynchronization therapy: Part 1--issues before device implantation

Cardiac resynchronization therapy (CRT) has been used extensively over the last years in the therapeutic management of patients with end-stage heart failure. Data from 4,017 patients have been published in eight large, randomized trials on CRT. Improvement in clinical end points (symptoms, exercise capacity, quality of life) and echocardiographic end points (systolic function, left ventricular size, mitral regurgitation) have been reported after CRT, with a reduction in hospitalizations for decompensated heart failure and an improvement in survival. However, individual results vary, and 20% to 30% of patients do not respond to CRT. At present, the selection criteria include severe heart failure (New York Heart Association functional class III or IV), left ventricular ejection fraction <35%, and wide QRS complex (>120 ms). Assessment of inter- and particularly intraventricular dyssynchrony as provided by echocardiography (predominantly tissue Doppler imaging techniques) may allow improved identification of potential responders to CRT. In this review a summary of the clinical and echocardiographic results of the large, randomized trials is provided, followed by an extensive overview on the currently available echocardiographic techniques for assessment of LV dyssynchrony. In addition, the value of LV scar tissue and venous anatomy for the selection of potential candidates for CRT are discussed.

Vitamin C improves endothelial function of conduit arteries in patients with chronic heart failure

BACKGROUND

Chronic heart failure (CHF) is associated with endothelial dysfunction including impaired endothelium-mediated, flow-dependent dilation (FDD). There is evidence for increased radical formation in CHF, raising the possibility that nitric oxide is inactivated by radicals, thereby impairing endothelial function. To test this hypothesis, we determined the effect of the antioxidant vitamin C on FDD in patients with CHF.

METHODS AND RESULTS

High-resolution ultrasound and Doppler was used to measure radial artery diameter and blood flow in 15 patients with CHF and 8 healthy volunteers. Vascular effects of vitamin C (25 mg/min IA) and placebo were determined at rest and during reactive hyperemia (causing endothelium-mediated dilation) before and after intra-arterial infusion of N-monomethyl-L-arginine (L-NMMA) to inhibit endothelial synthesis of nitric oxide. Vitamin C restored FDD in patients with heart failure after acute intra-arterial administration (13.2+/-1.7% versus 8.2+/-1.0%; P<.01) and after 4 weeks of oral therapy (11.9+/-0.9% versus 8.2+/-1.0%; P<.05). In particular, the portion of FDD mediated by nitric oxide (ie, inhibited by L-NMMA) was increased after acute as well as after chronic treatment (CHF baseline: 4.2+/-0.7%; acute: 9.1+/-1.3%; chronic: 7.3+/-1.2%; normal subjects: 8.9+/-0.8%; P<.01).

CONCLUSIONS

Vitamin C improves FDD in patients with CHF as the result of increased availability of nitric oxide. This observation supports the concept that endothelial dysfunction in patients with CHF is, at least in part, due to accelerated degradation of nitric oxide by radicals.

The clinical features of takotsubo cardiomyopathy

BACKGROUND

Cardiologists have recently recognized a reversible form of heart failure of unknown origin characterized by a takotsubo-shaped hypokinesis of the left ventricle on left ventriculography.

AIM

To clarify the clinical features of this cardiomyopathy.

DESIGN

Observational study.

METHODS

Seven patients with reversible ventricular dysfunction were followed for 4.5 years. Clinical course, routine examinations, and cardiac catheterizations in each patient were documented.

RESULTS

The cardiomyopathy developed in six elderly female and one male patients (mean age 75.3 years), all of whom had been exposed to stress. Cardiac enzymes did not significantly increase, but serum norepinephrine increased remarkably (1.19 ng/ml). Coronary angiography revealed normal coronary arteries. However, left ventriculography showed akinesis in the apical segments, together with hyperkinesis in the basal segments (a takotsubo shape). The abnormal kinesis normalized within 17.4 hospital days without any treatment in five patients, and with haemodynamic support for 3 days in the other two. Endocardial biopsies did not suggest any specific pathology. The cardiac events did not recur over a 1-4 year follow-up.

DISCUSSION

Coronary vasospasm, myocarditis and other substantial diseases previously described were ruled out as the cause of takotsubo cardiomyopathy in our subjects. Prognosis was good without any form of treatment, provided that the patients survived the severe heart failure state. Catecholaminergic or adrenoceptor-hyperactive cardiomyopathy may be the cause of this cardiomyopathy.

Free Fatty Acid Depletion Acutely Decreases Cardiac Work and Efficiency in Cardiomyopathic Heart Failure

Background— Metabolic modulators that enhance myocardial glucose metabolism by inhibiting free fatty acid (FFA) metabolism may improve cardiac function in heart failure patients. We studied the effect of acute FFA withdrawal on cardiac function in patients with heart failure caused by idiopathic dilated cardiomyopathy (IDCM).

Methods and Results— Eighteen fasting nondiabetic patients with IDCM (14 men, 4 women, aged 58.8±8.0 years, ejection fraction 33±8.8%) and 8 matched healthy controls underwent examination of myocardial perfusion and oxidative and FFA metabolism, before and after acute reduction of serum FFA concentrations by acipimox, an inhibitor of lipolysis. Metabolism was monitored by positron emission tomography and [ 15 O]H 2 O, [ 11 C]acetate, and [ 11 C]palmitate. Left ventricular function and myocardial work were echocardiographically measured, and efficiency of forward work was calculated. Acipimox decreased myocardial FFA uptake by >80% in both groups. Rate–pressure product and myocardial perfusion remained unchanged, whereas stroke volume decreased similarly in both groups. In the healthy controls, reduced cardiac work was accompanied by decreased oxidative metabolism (from 0.071±0.019 to 0.055±0.016 min −1 , P <0.01). In IDCM patients, cardiac work fell, whereas oxidative metabolism remained unchanged and efficiency fell (from 35.4±12.6 to 31.6±13.3 mm Hg · L · g −1 , P <0.05).

Conclusions— Acutely decreased serum FFA depresses cardiac work. In healthy hearts, this is accompanied by parallel decrease in oxidative metabolism, and myocardial efficiency is preserved. In failing hearts, FFA depletion did not downregulate oxidative metabolism, and myocardial efficiency deteriorated. Thus, failing hearts are unexpectedly more dependent than healthy hearts on FFA availability. We propose that both glucose and fatty acid oxidation are required for optimal function of the failing heart.

Does the 6-minute walk test predict the prognosis in patients with NYHA class II or III chronic heart failure?

BACKGROUND

We prospectively evaluated the potential of the 6-minute walk test compared with peak VO2 in predicting outcome of patients with New York Heart Association (NYHA) class II or III heart failure.

METHODS AND RESULTS

Patients with a history of heart failure caused by systolic dysfunction were included. The combined final outcome (death or hospitalization for heart failure) was used as the judgment criterion. One hundred twenty-one patients (age 59+/-11 years; left ventricular ejection fraction 29.6%+/-13%) were included and followed for 1.53+/-0.98 years. Patients were separated into two groups according to outcome: group 1 (G1, 74 patients), without events, and group 2 (G2, 47 patients), who reached the combined end point. Peak VO2 was clearly different between G1 and G2 (18.5+/-4 vs. 13.9+/-4 ml/kg/min, p=0.0001) but not the distance walked (448+/-92 vs 410+/-126 m; p=0.084, not significant). Survival analysis showed that unlike peak VO2, the distance covered was barely distinguishable between the groups (p < 0.08). However, receiver operating characteristic curves revealed that the best performances for the 6-minute walk test were obtained for subjects walking < or =300 m. These patients had a worse prognosis than those walking farther (p=0.013). In this subset of patients, there was a significant correlation between distance covered and peak VO2 (r=0.65, p=0.011). Thus it appears that the more severely affected patients have a daily activity level relatively close to their maximal exercise capacity. Nevertheless, the 300 m threshold suggested by this study needs to be validated in an independent population.

CONCLUSIONS

A distance walked in 6 minutes < or =300 m can predict outcome. Moreover, in these cases there is a significant correlation between the 6-minute walk test and peak VO2 demonstrating the potential of this simple procedure as a first-line screening test for this subset of patients.

Open access echocardiography in management of heart failure in the community

OBJECTIVE

To assess the value of an open access echocardiography service.

DESIGN

Study of new open access service for general practitioners, who were invited to refer patients taking diuretics for suspected heart failure, untreated patients with symptoms of possible heart failure, and asymptomatic patients with risk factors for left ventricular systolic dysfunction.

SETTING

Regional cardiology centre.

SUBJECTS

259 consecutive patients.

MAIN OUTCOME MEASURES

Presence or absence of left ventricular systolic dysfunction and consequent changes in clinical management.

RESULTS

119 treated patients, 99 untreated patients, and nine asymptomatic patients were referred over five months. 32 were considered to be inappropriately referred. Among the treated patients, 31 had impaired left ventricular systolic function and five had valvular disease; angiotensin converting enzyme inhibitors were recommended for 34 of these patients. In addition, 53 were thought not to need diuretics. Eight untreated patients had impaired systolic function and six valvular disease.

CONCLUSIONS

The service was well used by general practitioners and led to advice to change management in more than two thirds of patients.

Diastolic dysfunction and natriuretic peptides in systolic heart failure. Higher ANP and BNP levels are associated with the restrictive filling pattern

BACKGROUND

Left ventricular diastolic dysfunction is common in patients with systolic heart failure and the restrictive type of filling pattern appears to be associated with increased cardiac mortality. Both artrial and brain (or ventricular) natriuretic peptides are also proven markers of the severity of heart failure. The aim of this study was to determine in a large cohort of patients with systolic heart failure whether diastolic abnormalities, and in particular the restrictive filling pattern of transmitral flow velocity, correlate with plasma atrial and brain natriuretic peptide levels.

METHODS

Sixty-eight consecutive patients with symptomatic systolic heart failure (ejection fraction < 0.5) underwent two-dimensional Doppler echocardiography of left ventricular systolic and diastolic function, together with measurement of atrial and brain natriuretic peptides.

RESULTS

The restrictive filling pattern was present in 62%, the abnormal relaxation pattern in 31% and only 7% were normal. Atrial and brain natriuretic peptide (ANP/BNP) levels were significantly higher in the restrictive compared to the abnormal relaxation group (ANP: 202.2 +/- 31.7 vs 102.5 +/- 22.1 pg.ml-1, P = 0.012; BNP: 277.8 +/- 27.7 vs 162.4 +/- 21.9 pg.ml-1, P = 0.002). In addition, a restrictive filling pattern was associated with lower ejection fractions (P = 0.026), higher pulmonary artery systolic pressure (P < 0.001), larger left atrial size (P = 0.044), and were more likely to be in New York Heart Association class III or IV than those with an abnormal relaxation pattern (P = 0.007). Both atrial and brain natriuretic peptides correlated inversely with ejection fraction (P < 0.001), fractional shortening (P < 0.001), and positively with pulmonary artery pressure (P = 0.004 and 0.001 respectively). There were no significant correlations between single diastolic parameters and atrial or brain natriuretic peptide levels for the total patient group except between mitral peak A wave velocity and brain natriuretic peptides (r = -0.3, P = 0.01). For those with abnormal relaxation pattern mitral, valve E-wave deceleration time correlated significantly with both atrial and brain natriuretic peptide levels (P < 0.01).

CONCLUSIONS

This study confirms that the restrictive filling pattern of transmitral flow velocity is a marker of more severe heart failure, as indicated by its association with higher atrial and brain natriuretic peptide levels, lower ejection fraction and higher pulmonary artery pressure. Thus, this easily obtained Doppler-derived marker of diastolic dysfunction is useful for identifying those patients with more severe heart failure.

Cardiac Resynchronization Therapy

Encouraged by the clinical success of cardiac resynchronization therapy (CRT), the implantation rate has increased exponentially, although several limitations and unresolved issues of CRT have been identified. This review concerns issues that are encountered during implantation of CRT devices, including the role of electroanatomical mapping, whether CRT implantation should be accompanied by simultaneous atrioventricular nodal ablation in patients with atrial fibrillation, procedural complications, and when to consider surgical left ventricular lead positioning. Furthermore, (echocardiographic) CRT optimization and assessment of CRT benefits after implantation are highlighted. Also, controversial issues such as the potential value of CRT in patients with mild heart failure or narrow QRS complex are addressed. Finally, open questions concerning when to combine CRT with implantable cardioverter-defibrillator therapy and the cost-effectiveness of CRT are discussed.

Cardiac death prediction and impaired cardiac sympathetic innervation assessed by MIBG in patients with failing and nonfailing hearts

BACKGROUND

Although cardiac sympathetic nerve dysfunction is related to poor clinical outcome, a critical sympathetic dysfunction level for predicting cardiac death is still unclear. The current study was designed to investigate which indices derived from metaiodobenzylguanidine (MIBG) imaging have prognostic value compared with clinical and cardiac function variables, and to determine the threshold of cardiac MIBG activity for identifying patients likely to suffer cardiac death in both failing and nonfailing hearts.

METHODS AND RESULTS

Myocardial I-123-MIBG activity was quantified as a heart-to-mediastinum ratio in 414 consecutive patients, 173 (42%) of whom had symptomatic heart failure. After cardiac function measurements, patients were followed up with an end-point of cardiac or noncardiac death. During a mean follow-up period of 22 months, 37 cardiac deaths occurred: 23 resulted from heart failure, 9 were sudden cardiac deaths, and 5 were fatal myocardial infarctions. Multivariate analysis using the Wald chi2 and the Cox proportional hazard model revealed that late heart-to-mediastinum ratio, the use of nitrates, early heart-to-mediastinum ratio, and left ventricular ejection fraction were independent predictors of cardiac death; late heart-to-mediastinum ratio, New York Heart Association (NYHA) class, the presence of previous myocardial infarction, and age were independent predictors of heart failure and sudden cardiac death. Late heart-to-mediastinum ratio was the most powerful predictor of overall cardiac death among the variables. The Kaplan-Meier analysis showed that a late heart-to-mediastinum ratio of 1.74 or less, age greater than 60 years, the presence of myocardial infarction, and NYHA functional class 3 or 4 strongly indicated poor clinical outcomes. Furthermore, the more powerful incremental prognostic values were obtained by using MIBG imaging in combination with conventional clinical variables.

CONCLUSIONS

Impaired cardiac sympathetic innervation assessed by MIBG activity has the greatest potential for predicting cardiac death and may be useful for identifying a threshold level for selecting patients at risk for death by heart failure, sudden cardiac death, and fatal myocardial infarction.

Restrictive left ventricular diastolic filling identifies patients with heart failure after acute myocardial infarction

Left ventricular diastolic filling was characterized by transmitral pulsed-wave Doppler velocities in 62 patients with acute myocardial infarction, and diastolic filling variables were correlated with the presence of clinical heart failure. At the time of admission, 47 patients were free of heart failure and 15 patients were in Killip class II to IV. In the latter group of patients with heart failure, peak velocity of late filling wave caused by atrial contraction (A) was lower (0.48 versus 0.59 m/sec, p < 0.05), ratio of peak velocity of early rapid filling wave to peak velocity of late filling wave caused by atrial contraction (E/A) was higher (1.5 versus 1.1, p < 0.01), and deceleration time (136 versus 196 msec, p = 0.0001) was shorter when compared with the patients not in heart failure after acute myocardial infarction. Multivariate analysis showed that the deceleration time was a powerful independent predictor of presence of heart failure after controlling for systolic functional variables. Therefore, diastolic filling variables can complement systolic functional variables in the identification of the patients with postinfarction left ventricular failure.

Coronary artery stenting in the elderly: short-term outcome and long-term angiographic and clinical follow-up

OBJECTIVES

This study sought to compare the short- and long-term outcomes of elderly patients undergoing coronary artery stenting with those of younger patients and to determine the long-term clinical outcome and survival of elderly patients post stent implantation.

BACKGROUND

Elderly patients undergoing coronary revascularization are considered a high-risk group. Few data exist that relate the results of stenting in treating coronary artery disease in the elderly population.

METHODS

All elderly patients >75 years of age who underwent coronary artery stenting between March 1993 and July 1997 (n=137) at our center were compared to the patients <75 who underwent coronary artery stenting during the same time period (n=2,551). Long-term clinical follow-up and survival were determined for the elderly group.

RESULTS

Elderly patients presented with lower ejection fractions (54% vs. 58%, p=0.0001), more unstable angina (47% vs. 28%, p=0.0001), and more multivessel disease (78% vs. 62%, p= 0.0001) than younger patients. These older patients had higher rates of procedure related complications including procedural myocardial infarction (MI) (2.9% vs. 1.7%, p=0.2), emergency CABG (3.7% vs. 1.4%, p=0.04), and death (2.2% vs. 0.12%, p=0.0001). Angiographic follow-up, obtained in both groups, demonstrated significantly higher restenosis rates in the elderly versus younger patients (47% vs. 28%, p=0.0007). Longer term clinical follow-up, which was obtained only in the elderly group, showed that at a mean follow-up period of 12 months post coronary stenting, elderly survival free from death, MI, revascularization and angina was 54% and that their overall survival was 91%. Subanalysis of the elderly patients who died showed much higher incidence of combined unstable angina (80%), prior MI (60%), lower ejection fraction (46%), multivessel disease (100%) and complex lesions (100%) than the overall group.

CONCLUSIONS

Elderly patients who undergo coronary artery stenting have significantly higher rates of procedural complications and worse six month outcomes than younger patients, especially those who present with combined unstable angina, history of MI, EF < 50%, multivessel disease and complex lesions. Overall survival in the elderly population at 12 months postcoronary artery stenting was 91% and event-free survival was 54%.

The phase image: its relationship to patterns of contraction and conduction

To determine the relationship of phase changes and abnormalities of ventricular contraction and conduction, we performed phase image analysis of blood pool scintigrams in 29 patients. Eleven patients had no evidence of blood pool contraction or ECG conduction abnormalities, four had contraction abnormalities, seven had abnormal conduction and seven had abnormalities of both variables. The phase delay generally related to the degree of contraction abnormality. The mean phase delay in hypokinetic segments differed from that in normokinetic segments in the same patient (p less than 0.025), the phase delay of akinetic and dyskinetic segments differed from that in normokinetic segments (p less than 0.001) and the phase delay in dyskinetic segments differed from that in akinetic segments (p less than 0.005), but there was a significant overlap in the phase delay in normal and hypokinetic segments. Also, in patients with conduction abnormalities, the minimal associated regional phase delay presented a phase dispersion and a pattern of contraction consistent with the pattern of conduction and different from normal. A single study performed both at rest and with stress demonstrated the effect of heart rate on phase assessment and confirmed the independent effects of contraction and conduction on phase delay. Acquisition and analytic methods should add significantly to the resolution of the phase method.

Septal to Posterior Wall Motion Delay Fails to Predict Reverse Remodeling or Clinical Improvement in Patients Undergoing Cardiac Resynchronization Therapy

OBJECTIVES

The aim of this study was to test the hypothesis that a longer septal-to-posterior wall motion delay (SPWMD) would predict greater reverse remodeling and an improved clinical response in heart failure patients randomized to cardiac resynchronization therapy (CRT) in the CONTAK-CD trial.

BACKGROUND

The SPWMD predicted clinical benefit with CRT in two previous studies from the same center.

METHODS

In this retrospective analysis of the CONTAK-CD trial, SPWMD was measured from the baseline echocardiogram of 79 heart failure patients (ejection fraction 22 +/- 7%, QRS duration 159 +/- 27 ms, 72% ischemic, 84% male) randomized to CRT and compared with six-month changes in echocardiographic and clinical parameters. Patients with a left ventricular end-systolic volume index (LVESVI) reduction of at least 15% were considered responders.

RESULTS

The feasibility and reproducibility of performing the SPWMD measurements were poor. Larger values for SPWMD did not correlate with six-month changes in left ventricular end-diastolic volume index (p = 0.26), LVESVI (p = 0.41), or left ventricular ejection fraction (p = 0.36). Responders did not have a significantly different SPWMD than non-responders (p = 0.26). The SPWMD did not correlate with measures of clinical improvement. At a threshold of SPWMD >130 ms, the test characteristics to predict reverse remodeling or a clinical response were inadequate.

CONCLUSIONS

The previous findings that SPWMD predicts reverse remodeling or clinical improvement with CRT were not reproducible in patients randomized in the CONTAK-CD trial.

Left Ventricular Dyssynchrony Predicts Right Ventricular Remodeling After Cardiac Resynchronization Therapy

OBJECTIVES

The purpose of this research was to evaluate right ventricular (RV) remodeling after six months of cardiac resynchronization therapy (CRT).

BACKGROUND

Cardiac resynchronization therapy is beneficial in patients with end-stage heart failure. The effect of CRT on RV size is currently unknown. Accordingly, the effects of CRT on RV size, severity of tricuspid regurgitation, and pulmonary artery pressure were evaluated.

METHODS

Fifty-six consecutive patients with end-stage heart failure (52% ischemic cardiomyopathy), left ventricular (LV) ejection fraction (EF) < or =35%, QRS duration >120 ms, and left bundle branch block were included. Clinical parameters, LV volumes, LVEF, LV dyssynchrony, and RV chamber size were assessed at baseline and after six months of CRT; LV dyssynchrony was assessed using tissue Doppler imaging.

RESULTS

Clinical parameters improved significantly; LV dyssynchrony was acutely reduced after CRT and remained unchanged at six-month follow-up. Left ventricular EF improved significantly from 19 +/- 6% to 26 +/- 8% (p < 0.001), and LV end-diastolic volume decreased from 257 +/- 98 ml to 227 +/- 86 ml (p < 0.001). Right ventricular annulus decreased significantly from 37 +/- 9 mm to 32 +/- 10 mm, RV short-axis from 29 +/- 11 mm to 26 +/- 7 mm, and RV long-axis from 89 +/- 11 mm to 82 +/- 10 mm (all p < 0.001). Left ventricular and RV reverse remodeling were only observed in patients with substantial LV dyssynchrony at baseline. Finally, significant reductions in severity of tricuspid regurgitation and pulmonary artery pressure were observed.

CONCLUSIONS

Cardiac resynchronization therapy results in significant reverse LV and RV remodeling after six months of CRT in patients with LV dyssynchrony. Moreover, CRT leads to a reduction of the severity of tricuspid regurgitation and a decrease in pulmonary artery pressure.

Heterozygous knockout of neuregulin-1 gene in mice exacerbates doxorubicin-induced heart failure

Neuregulins and their erbB receptors are essential for cardiac development and postulated to be cardioprotective in the presence of injury in the postnatal heart. We tested the hypothesis that the development of doxorubicin-induced cardiotoxicity in vivo is more severe in mice with heterozygous knockout of the neuregulin-1 gene (NRG-1(+/-)) compared with wild-type mice (WT). Three-month old NRG-1(+/-) and WT mice were injected with a single dose of doxorubicin (20 mg/kg ip). Survival was analyzed by the Kaplan-Meier approach. Left ventricular (LV) function and signaling pathways were analyzed 4 days after treatment. Fifteen days after treatment, survival was significantly lower in doxorubicin-treated NRG-1(+/-) mice (NRG-1(+/-)-Dox) compared with doxorubicin-treated WT mice (WT-Dox) (15% vs. 33%, P < 0.01). LV mass was significantly lower in NRG-1(+/-)-Dox but not in WT-Dox compared with nontreated animals. LV systolic pressure and LV midwall fractional shortening were significantly lower in NRG-1(+/-)-Dox compared with WT-Dox mice. LV protein levels of NRG-1, erbB2, and erbB4 receptors were similar in WT-Dox and NRG-1(+/-)-Dox mice. However, levels of phosphorylated erbB2, Akt, and ERK-1/2 were significantly decreased in NRG-1(+/-)-Dox compared with WT-Dox mice. A significant decrease in phosphorylated P70S6K levels was also observed in NRG-1(+/-)-Dox compared with nontreated NRG-1(+/-) mice. These results demonstrate that heterozygous knockout of the neuregulin-1 gene worsens survival and LV function in the presence of doxorubicin-induced cardiac injury in vivo. This is associated with the depression of activation of the erbB2 receptor as well as Akt, p70S6K, and ERK-1/2 pathways.

Balloon atrial septostomy for left ventricular decompression in patients receiving extracorporeal membrane oxygenation for myocardial failure

We describe the use of balloon atrial septostomy to decompress the left ventricle in four patients receiving extracorporeal membrane oxygenation for acute intractable myocardial failure. These patients were becoming clinically worse and had evidence of left ventricular and left atrial hypertension either by direct measurement or echocardiography. Atrial decompression was accomplished by blade septostomy in one patient and by balloon atrial septostomy under echocardiographic guidance at the bedside in three patients. Three of four patients improved after balloon atrial septostomy and survived. This procedure may be helpful in selected patients receiving extracorporeal membrane oxygenation for myocardial failure with evidence of increased left atrial pressure as a result of increased ventricular pressure.

Lower cardiac output is associated with greater white matter hyperintensities in older adults with cardiovascular disease

OBJECTIVES

To preliminarily examine the association between cardiac output, a measure of systemic blood flow, and structural brain magnetic resonance imaging indices of white matter hyperintensities (WMHs).

DESIGN

Cross-sectional.

SETTING

University medical setting.

PARTICIPANTS

Thirty-six older adults without dementia with prevalent cardiovascular disease (aged 56-85).

MEASUREMENTS

Cardiac output, WMHs.

RESULTS

Partial correlations, adjusting for age and history of hypertension, yielded an inverse relationship between WMHs adjacent to subcortical nuclei and cardiac output (correlation coefficient=-0.48, P=.03); as cardiac output decreased, WMHs increased significantly. No significant associations were found between cardiac output and total WMHs or periventricular WMHs.

CONCLUSION

These preliminary data suggest that systemic blood flow, measured according to cardiac output, is inversely associated with WMHs adjacent to the subcortical nuclei. Cerebrovascular degeneration and the chronicity of hypoperfusion may exacerbate the susceptibility of white matter integrity to alterations in blood flow in older adults.

Cardioprotective mechanisms of eplerenone on cardiac performance and remodeling in failing rat hearts

Aldosterone may play a pivotal role in the pathophysiology of heart failure. To elucidate the beneficial cardioprotective mechanism of eplerenone, a novel selective aldosterone blocker, we hypothesized that eplerenone stimulates endothelial NO synthase (eNOS) through Akt and inhibits inducible NO synthase (iNOS) via nuclear factor kappaB (NF-kappaB) after the development of oxidative stress and activation of the lectin-like, oxidized, low-density lipoprotein receptor 1 (LOX-1) pathway in Dahl salt-sensitive rats with heart failure. Eplerenone (10, 30, and 100 mg/kg per day) was given from the age of the left ventricular hypertrophy stage (11 weeks) to the failing stage (18 weeks) for 7 weeks. The left ventricular end-systolic pressure-volume relationship was evaluated using a conductance catheter. Decreased percentage of fractional shortening by echocardiography and end-systolic pressure-volume relationship in failing rats was significantly ameliorated by eplerenone. Downregulated eNOS expression, eNOS and Akt phosphorylation, and NOS activity in failing rats were increased by eplerenone. Upregulated expression of the mineralocorticoid receptor aldosterone synthase (CYP11B2); NAD(P)H oxidase p22phox, p47phox, gp91phox, iNOS, and LOX-1; and activated p65 NF-kappaB, protein kinase CbetaII, c-Src, p44/p42 extracellular signal-regulated kinase, and p70S6 kinase phosphorylation were inhibited by eplerenone. Eplerenone administration resulted in significant improvement of cardiac function and remodeling and upregulation of sarcoplasmic reticulum Ca(2+)-ATPase expression. These findings suggest that eplerenone may have significant therapeutic potential for heart failure, and these cardioprotective mechanisms of eplerenone may be mediated in part by stimulating eNOS through Akt and inhibiting iNOS via NF-kappaB after activation of the oxidative stress-LOX-1 pathway and signal transduction pathway.

Plasma aldosterone levels are elevated in patients with pulmonary arterial hypertension in the absence of left ventricular heart failure: a pilot study

AIMS

Elevated levels of the mineralocorticoid hormone aldosterone are recognized as a modifiable contributor to the pathophysiology of select cardiovascular diseases due to left heart failure. In pulmonary arterial hypertension (PAH), pulmonary vascular remodelling induces right ventricular dysfunction and heart failure in the absence of left ventricular (LV) dysfunction. Hyperaldosteronism has emerged as a promoter of pulmonary vascular disease in experimental animal models of PAH; however, the extent to which hyperaldosteronism is associated with PAH in patients is unknown. Thus, the central aim of the current study is to determine if hyperaldosteronism is an unrecognized component of the PAH clinical syndrome.

METHODS AND RESULTS

Plasma aldosterone levels and invasive cardiopulmonary haemodynamic measurements were obtained for 25 patients referred for evaluation of unexplained dyspnoea or pulmonary hypertension. Compared with controls (n = 5), patients with PAH (n = 18) demonstrated significantly increased plasma aldosterone levels (1200.4 ± 423.9 vs. 5959.1 ± 2817.9 pg/mL, P < 0.02), mean pulmonary artery pressure (21.4 ± 5.0 vs. 45.5 ± 10.4 mmHg, P < 0.002), and pulmonary vascular resistance (PVR) (1.41 ± 0.6 vs. 7.3 ± 3.8 Wood units, P < 0.003) without differences in LV ejection fraction or pulmonary capillary wedge pressure between groups. Among patients not prescribed PAH-specific pharmacotherapy prior to cardiac catheterization, a subgroup of the cohort with severe pulmonary hypertension, aldosterone levels correlated positively with PVR (r = 0.72, P < 0.02) and transpulmonary gradient (r = 0.69, P < 0.02), but correlated inversely with cardiac output (r = -0.79, P < 0.005).

CONCLUSIONS

These data demonstrate a novel cardiopulmonary haemodynamic profile associated with hyperaldosteronism in patients: diminished cardiac output due to pulmonary vascular disease in the absence of LV heart failure.