Reverse remodeling in heart failure with intensification of vasodilator therapy

The Role of Arterial Hypertension in Mitral Valve Regurgitation

PURPOSE OF REVIEW

To review medical literature for evidence of association between hypertension and mitral regurgitation (MR) and summarize potential favorable effects of antihypertensive drugs on MR natural history and treatment.

RECENT FINDINGS

Hypertension and MR are common diseases affecting a large proportion of the general population. Contemporary evidence suggests that hypertension may worsen the progression and prognosis of MR through augmented mechanical stress and increased regurgitation volume. Renin-angiotensin axis inhibitors, beta-blockers, and vasodilators have been tested in order to prevent or decrease primary or secondary MR. Although antihypertensive agents may improve hemodynamic parameters and left ventricular remodeling in primary MR, there is no strong evidence of benefit on clinical outcomes. On the other hand, a beneficial effect of these drugs on secondary MR is better established. Moreover, there are no studies evaluating a possible benefit of lower blood pressure targets in MR. Randomized controlled trials are warranted to elucidate the precise role of antihypertensive therapy on treatment of MR.

Developing Drugs for Heart Failure With Reduced Ejection Fraction: What Have We Learned From Clinical Trials?

There remains a large unmet need for new therapies in the treatment of heart failure with reduced ejection fraction (HFrEF). In the early drug development phase, the therapeutic potential of a drug is not yet fully understood and trial endpoints other than mortality are needed to guide drug development decisions. While a true surrogate marker for mortality in heart failure (HF) remains elusive, the successes and failures of previous trials can reveal markers that support clinical Go/NoGo decisions.

Reverse Cardiac Remodeling: A Marker of Better Prognosis in Heart Failure

In heart failure syndrome, myocardial dysfunction causes an increase in neurohormonal activity, which is an adaptive and compensatory mechanism in response to the reduction in cardiac output. Neurohormonal activity is initially stimulated in an attempt to maintain compensation; however, when it remains increased, it contributes to the intensification of clinical manifestations and myocardial damage. Cardiac remodeling comprises changes in ventricular volume as well as the thickness and shape of the myocardial wall. With optimized treatment, such remodeling can be reversed, causing gradual improvement in cardiac function and consequently improved prognosis.

Dobutamine as bridge to angiotensin-converting enzyme inhibitor-nitrate therapy in endstage heart failure

BACKGROUND

Intravenous inotropic intervention in congestive heart failure is generally associated with a poor prognosis and is largely used as a "bridge" to mechanical support or heart transplantation.

HYPOTHESIS

We hypothesized that the inotropic support afforded by dobutamine may serve as a bridge to the introduction and intensification of angiotensin-converting enzyme (ACE) inhibitor-nitrate therapy.

METHODS

We studied the efficacy of transitioning inotrope-dependent patients in endstage heart failure from intravenous dobutamine to high-dose ACE inhibitor-nitrates, with 1-year follow-up. Forty-nine sequential dobutamine-dependent patients with left ventricular ejection fraction (LVEF) 17+/-17% were treated with increasing lisinopril (1.9+/-1.5 to 46+/-28 mg/day) and isosorbide dinitrate (7+/-6 to 229+/-161 mg/day). Outpatient dobutamine was continued or repeat infusions pursued, as indicated, and dobutamine was tapered when feasible.

RESULTS

During the following year, 14 of 49 patients required repeat dobutamine, with home treatment with dobutamine for 6.3+/-3.7 months (n = 5). At 1 year, New York Heart Association (NYHA) classification improved from 3.6+/-0.5 to 1.9+/-1.0, p < 0.0001; yearly hospitalizations fell from 2.7+/-2.3 to 1.2+/-3.0, p = 0.02; and LVEF rose from 17+/-7% to 24+/-11%, p < 0.0001. At 1 year, 14 patients who remained dobutamine dependent had significantly more severe symptoms than dobutamine-independent patients (n = 35). Transplant or death occurred in 7 of 14 patients with follow-up dobutamine, and in 5 of 35 patients free of subsequent dobutamine, p = 0.03. Patients with poor outcome (transplant n = 10, death n = 12) continued to be more limited (NYHA 2.7+/-0.9 vs. 1.7+/-0.9, p = 0.0002), with more follow-up hospitalizations (3.6+/-5.4 vs. 0.6+/-0.8, p = 0.0004), and no improvement in LVEF (17+/-8vs. 28+/-11%, p = 0.003).

CONCLUSIONS

Of the patients on dobutamine inotropic support, 70% were successfully transitioned to ACE inhibitor-nitrate therapy, with improved symptoms and LVEF, and with reduced hospitalizations and follow-up dobutamine or transplant. Thirty percent of patients with continued need for dobutamine had a significantly poorer 1-year clinical outcome.

The impact of beta-receptor blocker addition to high-dose angiotensin-converting enzyme inhibitor-nitrate therapy in heart failure

BACKGROUND

The natural history of heart failure is one of continued worsening of cardiac function. Beta-receptor blocker therapy has been effective in improving clinical status and left ventricular function in patients with heart failure. Similarly, high doses of angiotensin-converting enzyme (ACE) inhibitors with nitrates partially reverse the ventricular remodeling of heart failure.

HYPOTHESIS

We tested the hypothesis that beta-blocker therapy added to high-dose ACE inhibitor-nitrates would potentiate the reversal of heart failure.

METHODS

Thirteen patients, aged 52 +/- 8 years, with moderate to severe heart failure, 12 of whom were referred for transplant consideration, with heart failure duration of 4.8 +/- 2.2 years, were prospectively followed for 12 months. Baseline echocardiographic ejection fraction was 19 +/- 8%, and presenting New York Heart Association class was 2.9 +/- 0.7. Angiotensin-converting enzyme inhibitors and nitrates were uptitrated over 6 months to a final dose of lisinopril 53 +/- 31 mg/day, and isosorbide dinitrate 217 +/- 213 mg/day. At 6 months, beta-blocker therapy with atenolol was initiated and titrated to a final dose of 46 +/- 23 mg/day. Two-dimensional Doppler echocardiography and metabolic stress testing were performed at baseline, at 6 months on lisinopril-nitrates only, and at 12 months on combined ACE inhibitor-nitrate and beta-blocker therapy.

RESULTS

New York Heart Association classification improved from 2.9 +/- 0.7 to 1.8 +/- 0.8 on lisinopril-nitrates (p < 0.05), and to 1.5 +/- 0.5 with the addition of beta blockade (p = NS). On follow-up, peak oxygen consumption rose from 17 +/- 7 ml O2/kg/min at baseline to 21 +/- 5 ml O2/kg/min at 6 months on lisinopril-nitrates (p = 0.06) without further change on beta blockade. Ejection fraction rose from 19 +/- 8 to 33 +/- 14% on lisinopril-nitrates at 6 months (p = 0.005) and to 36 +/- 18% on beta blockade at 12 months (p = NS).

CONCLUSION

High-dose ACE inhibitor-nitrate therapy significantly improved patient clinical status and left ventricular systolic function in heart failure. The addition of beta-receptor blockade over and above high-dose ACE inhibitor-nitrates was well tolerated but had no further impact on symptomatic status, exercise tolerance, or left ventricular systolic function. The potential for pharmacologic reversal of heart failure remodeling may be finite despite the use of complementary therapies. Larger placebo-controlled and randomized trials of beta-receptor blockade added to high-dose ACE inhibitor-nitrate therapy are needed to confirm these observations.

Impact of left ventricular size on pharmacologic reverse remodeling in heart failure

BACKGROUND AND HYPOTHESIS

Although medical therapy may normalize echocardiographic left ventricular (LV) systolic function in selected patients with cardiomyopathy, other patients experience no change or a further deterioration in heart failure remodeling. Our aim was to determine what clinical or echocardiographic parameters predict a beneficial therapeutic response.

METHODS

We prospectively followed biannual clinical and echocardiographic assessments in 215 patients. Forty-six of these patients ("Nonresponders") experienced no change or a decline in LV ejection fraction at 6 months. Of the 148 patients who improved LV function, 21 ("Responders") normalized LV systolic function at 6 months. Only Responders (n = 21) and Nonresponders (n = 46) were compared.

RESULTS

On average, these 67 patients were 54 +/- 12 years old with 4.5 +/- 3.3 years of heart failure. At 6 months, following up-titration of angiotensin-converting enzyme inhibitors and nitrates, Responder LV ejection fraction rose from 22 +/- 6 to 50 +/- 5% with improvement in New York Heart Association classification (2.6 +/- 0.8 to 1.5 +/- 0.8, p = 0.001). These patients had significantly more favorable clinical and echocardiographic outcomes versus Nonresponders despite comparable medical therapy. All baseline demographic, clinical, and echocardiographic variables were equivalent, except for initial LV end-diastolic diameter which differentiated Nonresponders (7.1 +/- 0.7 cm) from Responders (6.1 +/- 0.8 cm), p = 0.007.

CONCLUSION

Thus, although heart failure therapy improves LV systolic function in a majority of patients, with normalization in up to 10% of patients, significant LV enlargement may render remodeling unresponsive to pharmacologic intervention, with a potential future need for alternative mechanical or surgical intervention.

Is magnetic resonance imaging the 'reference standard' for cardiac functional assessment? Factors influencing measurement of left ventricular mass and volumes

PURPOSE

MRI is considered reference standard for the assessment of left ventricular (LV) volume and mass measurements. There are few accepted guidelines for uniform assessment of cardiac function with MRI. We sought to investigate different confounding factors influencing LV measurement results.

MATERIAL AND METHODS

In 60 diabetic type-II patients (group A) we compared intra-/inter-reader variability of MRI for cardiac function measured twice at a 3 month interval by one MRI trained reader and one untrained. In 20 patients (group B) two different techniques were compared for determining the epicardial and endocardial LV-borders.

RESULTS

Bland Altman analysis showed excellent intra-observer measurement agreement for the trained reader 1 for EDM (mean = -2.3 (-23.6-19)), EDV (2.9(-9.2-15.0)), ESV (3.3(-5.8-12.4)) and EF (1.2(-3.3-5.7)). Untrained reader 2 measurement agreement was considerably less appropriate for EDM (mean = -8.2 (-25.8-9.5)), EDV (7.8(-5.1-20.7)), ESV (5.3(-8.0-18.6)). Only for EF (0.8 (-6.5-8.1)) results were comparable to reader 1. Inter-observer measurement in the beginning was poor for EDM (-13.5(-55.6-28.6)) and EDV (7.3(-61.9-76.6)), whereas agreement for ESV (2.1(-29.9-34.2)) and EF (-0.9(-11.6-9.9)) was good. After 3 months, measurement agreement for EDM (-5.3 (-46.4-35.8)) was considerably improved, for EDV (0.4(-67.0-66.2)) was excellent, whereas agreement for ESV (3.1(-34.4-28.1)) and EF (-1.7(-13.0-9.6)) was similar. Using different techniques for determining the epicardial and endocardial borders, only end-diastolic volume was unchanged whereas all other parameters were significantly different using the two methods (p < or = 0.03).

CONCLUSION

Intra- and inter-reader variability, analyst experience as well as different techniques for determining the boundaries of the left ventricle significantly affect MRI parameters for cardiac function. These results suggest a need for developing commonly accepted standards for cardiac MRI evaluation.

Pharmacological left ventricular reverse remodeling in elderly patients receiving optimal therapy for chronic heart failure

BACKGROUND AND AIMS

In recent years, reversal of established left ventricular (LV) dilatation has been increasingly recognized in middle-aged patients with dilated cardiomyopathy receiving angiotensin-converting enzyme (ACE) inhibitors and/or beta-blockers. We performed this prospective study to evaluate whether optimized therapy for heart failure also induces LV reverse remodeling in older patients.

METHODS

One hundred and twenty-four patients aged >70 years with LV ejection fraction <40% underwent clinical and echocardiographic evaluation at baseline and after 1 year. During the early stage of follow-up, pharmacological therapy was optimized. LV reverse remodeling was defined as a reduction in LV end-diastolic volume >25% from baseline to final evaluation.

RESULTS

LV reverse remodeling was recognized in 32 patients (26%). Compared to the subjects who did not improve LV geometry, those with reverse remodeling had, at baseline, higher arterial blood pressure, lower serum creatinine levels, shorter duration of symptoms of heart failure, more frequently received beta-blocker therapy and had predominantly nonischemic aetiology. The variables associated with the development of reverse remodeling in the multivariate analysis were shorter duration of symptoms of heart failure (Odds ratio: 7.7; CI: 2.5-23.3, p=0.0001) and beta-blocker therapy (Odds ratio: 6.0; CI: 1.6-23.3, p=0.01).

CONCLUSIONS

LV reverse remodeling takes place in elderly as well as in younger heart failure patients. A significant proportion of elderly patients undergoes this favourable process which occurs prevalently in patients receiving beta-blocker therapy with a short history of cardiac disease.

What is the Optimal Angiotensin‐Converting Enzyme Inhibitor Dose in Heart Failure?

Doses of angiotensin-converting enzyme (ACE) inhibitors used in the landmark heart failure trials that demonstrated survival benefit are rarely reached in routine practice. The authors review the current literature regarding optimal dosing of ACE inhibitors in heart failure with specific focus on neurohormonal, functional capacity, and clinical outcomes. Neurohormonal studies have shown that lower ACE inhibitor dosing may provide inadequate suppression of the renin-angiotensin-aldosterone system. Higher doses of ACE inhibitors have resulted in greater increments in exercise and functional capacity. Clinically, patients on high-dose ACE inhibitor therapy had significant reductions in all-cause mortality or hospitalization, cardiovascular hospitalizations, and heart failure-specific hospitalizations. There is, however, conflicting evidence, and so continued uncertainty exists regarding optimal dosing. Despite underutilization of ACE inhibitors, there is insufficient evidence to support lower doses. Likewise, limited data exist for doses higher than those used in the landmark trials. Clinicians should therefore attempt to reach target doses in heart failure whenever possible.

Cardiovascular Function in Multi-Ethnic Study of Atherosclerosis: Normal Values by Age, Sex, and Ethnicity

OBJECTIVE

MRI provides accurate and high-resolution measurements of cardiac anatomy and function. The purpose of this study was to describe the imaging protocol and normal values of left ventricular (LV) function and mass in the Multi-Ethnic Study of Atherosclerosis (MESA).

SUBJECTS AND METHODS

Eight hundred participants (400 men, 400 women) in four age strata (45-54, 55-64, 65-74, 75-84 years) were chosen at random. Participants with the following known cardiovascular risk factors were excluded: current smoker, systolic blood pressure > 140 mm Hg, diastolic blood pressure > 90 mm Hg, fasting glucose > 110 mg/dL, total cholesterol > 240 mg/dL, and high-density lipoprotein (HDL) cholesterol < 40 mg/dL. Cardiac MR images were analyzed using MASS software (version 4.2). Mean values, SDs, and correlation coefficients in relationship to patient age were calculated.

RESULTS

There were significant differences in LV volumes and mass between men and women. LV volumes were inversely associated with age (p < 0.05) for both sexes except for the LV end-systolic volume index. For men, LV mass was inversely associated with age (slope = -0.72 g/year, p = 0.0021), but LV mass index was not associated with age (slope = -0.179 g/m2/year, p = 0.075). For women, LV mass (slope = -0.15 g/year, p = 0.30) and LV mass index (slope = 0.0044 g/m2/year, p = 0.95) were not associated with age. LV mass was the largest in the African-American group (men, 181.6 +/- 35.8 [SD] g; women, 128.8 +/- 28.1 g) and was smallest in the Asian-American group (men, 129.1 +/- 20.0 g; women, 89.4 +/- 13.3 g).

CONCLUSION

The normal LV differs in volume and mass between sexes and among certain ethnic groups. When indexed by body surface area, LV mass was independent of age for both sexes. Studies that assess cardiovascular risk factors in relationship to cardiac function and structure need to account for these normal variations in the population.

Effect of angiotensin-converting enzyme or vasopeptidase inhibition on ventricular size and function in patients with heart failure: the Omapatrilat Versus Enalapril Randomized Trial of Utility in Reducing Events (OVERTURE) echocardiographic study

BACKGROUND

Angiotensin-converting enzyme (ACE) inhibition attenuates ventricular remodeling and improves ventricular function in heart failure patients. Vasopeptidase inhibition has shown similar effects in experimental models.

OBJECTIVES

The OVERTURE echocardiographic study was designed to test the hypothesis that the vasopeptidase inhibitor omapatrilat would attenuate ventricular remodeling and improve ventricular function to a greater extent than an ACE inhibitor.

METHODS

Three hundred twenty-one patients with heart failure (New York Heart Association class > or = 2) were included in the OVERTURE echocardiographic substudy and were randomized to receive enalapril (10 mg twice a day) or omapatrilat (40 mg every day). Echocardiograms were performed at baseline and at 1 year (n = 214). Left ventricular size was estimated by summation of ventricular areas in apical and short-axis views and by calculation of ventricular volumes. Ejection fraction was calculated from ventricular volumes.

RESULTS

Combined diastolic and systolic areas and volumes decreased significantly (mean diastolic area change -8.36 cm2, 95% CI -9.4 to -7.3 cm2; mean systolic change -8.4 cm2, 95% CI -9.5 to -7.3 cm2), and ejection fractions increased significantly (3.6%, 95% CI 2.6% to 4.6%) in both treatment groups from baseline to 1 year. There were no differences in the magnitude of improvement in ventricular size or function based on treatment assignment. Patients who died or were hospitalized for heart failure subsequent to the final assessment demonstrated the least degree of reverse remodeling.

CONCLUSION

Ventricular size and function improved similarly after 1 year with ACE or vasopeptidase inhibition in patients with heart failure. Reverse remodeling was associated with improved outcome.

Rationale for the use of angiotensin ii receptor blockers in patients with left ventricular dysfunction (part I of II)

Almost 5 million individuals in the United States are diagnosed with chronic heart failure (HF), and the prevalence is increasing. Angiotensin-converting enzyme (ACE) inhibitors and beta blockers, neurohormonal antagonists that block the renin-angiotensin system (RAS) and the sympathetic nervous system, respectively, have been shown in clinical trials to reduce morbidity and mortality in patients with HF, and these therapies are now integral components of standard HF treatment. Yet, morbidity and mortality rates in HF remain unacceptably high, and the limitations of current standard therapies are becoming increasingly apparent. About 10% of patients with HF are unable to tolerate ACE inhibitors, often because of cough. In addition, ACE inhibition may not completely block the RAS because angiotensin II, the main end product of the RAS, can be generated via non-ACE enzymatic pathways. Angiotensin II receptor blockers (ARBs) may exert more complete RAS blockade than ACE inhibitors by interfering with the binding of angiotensin II at the receptor level, regardless of the enzymatic pathway of production. They are also better tolerated than ACE inhibitors and have been shown to improve symptoms and function in clinical trials in patients with HF. These factors provide a strong rationale for the study of the clinical effects of ARBs in patients with HF.

Nitrate tolerance and the links with endothelial dysfunction and oxidative stress

Identification of nitric oxide as the molecule responsible for endothelial dependant vasodilatation has led to an explosion of interest in endothelial function. Oxidative stress has been identified as an important factor in the development of tolerance to organic nitrates. This review examines the evidence supporting this recently developed theory and how mechanisms of nitrate tolerance may link with the wider picture of primary nitric oxide resistance.

Reversal of heart failure remodeling: is it maintained?

BACKGROUND

Reversal of heart failure remodeling has been observed with intensive heart failure therapy.

HYPOTHESIS

We hypothesized that reversal of heart failure remodeling may not be sustained in long-term follow-up.

METHODS

Sixty-one sequential patients with heart failure and left ventricular ejection fraction < or = 35%, who improved their ejection fraction by > or = 10% over baseline at follow-up, were prospectively followed and retrospectively analyzed. Each patient underwent echocardiography at baseline and biannually thereafter.

RESULTS

In all patients, left ventricular ejection fraction increased from 18 +/- 7% to 42 +/- 12% on uptitrated medical therapy. At follow-up over 20 +/- 8 (+/- standard deviation) months, this improvement was sustained in 38 patients ("Improved"). A relapse in remodeling occurred in the remaining 23 patients ("Relapsed"), with ejection fraction falling to 24 +/- 7%. For Improved and Relapsed patients, baseline echocardiographic and clinical parameters were equivalent. However, Improved patients tended to be younger, with shorter heart failure duration. Improved patients had more effective improvement in ejection fraction than Relapsed patients (45 +/- 13% vs. 36 +/- 8%, p = 0.005), with greater reductions in chamber size and mitral regurgitation.

CONCLUSION

Reversal of heart failure remodeling may be sustained in only two-thirds of patients at long-term follow-up. In contrast to Relapsed patients, Improved patients tended to be younger, with shorter heart failure duration and a more complete recovery of left ventricular systolic function.

Heart failure disease management: impact on hospital care, length of stay, and reimbursement

Congestive heart failure (CHF) is a major medical problem with significant hospital costs. The authors developed an inpatient disease management program for CHF in a community hospital setting to determine if it is possible to: 1) increase implementation of Agency for Health Care Policy and Research criteria for CHF; 2) improve the quality of patient care, while lowering length of stay and treatment cost for CHF; and 3) maintain nursing staff satisfaction. The program encompassed a clinical pathway incorporating Agency for Health Care Policy and Research criteria for CHF, CHF education, and patient educational materials. When compared to "unmanaged" patients (n=197) not participating in the algorithm due to physician choice, "managed" patients (n=396) had significantly increased documentation of left ventricular dysfunction and of angiotensin-converting enzyme inhibitor use. In contrast to unmanaged patients, managed patients had a significantly lower length of stay (3.9+/-2.2 vs. 6.1+/-2.8 days; p<0.0001) with a significant reduction in cost per patient ($4404+/-$1989 vs. $6828+/-$3347; p<0.0001). These changes were sustained in follow-up over 1 year and were associated with an improvement in nursing staff education and nursing care. Thus, a disease management program for CHF can be successfully implemented in a general community hospital setting, achieving improved compliance with Agency for Health Care Policy and Research treatment criteria and enhancing patient care, while reducing length of stay and cost.

Reversal of heart failure remodeling with age

Since heart failure is a major cause of morbidity in the elderly, we studied the effect of up-titrated heart failure therapy in older vs. younger individuals on symptoms and left ventricular (LV) function over 1 year. Seventy-one patients with heart failure and an LV ejection fraction < or =35% were enrolled and were followed with echocardiography at baseline and at 1 year. Young patients were born in or after 1935 (n=48; 51.7+/-9.1 years); middle-aged were born between 1925-1934 (n=14; 69.7+/-2.8 years); and older patients in or prior to 1924 (n=9; 80.5+/-3.3 years). Baseline LV ejection fraction was 18%+/-7%, LV end-diastolic diameter 6.9+/-0.9 cm, and New York Heart Association class was 2.6+/-1.0, equivalent for all groups. On medical therapy, at 12 months, LV ejection fraction improved only for the young and middle-aged (36%+/-14% and 37%+/-17%; p=0.002), but not for the older patients (22%+/-7%; p=NS). Reductions in LV end-diastolic diameter and mitral regurgitation were significant only for the young. However, New York Heart Association status improved similarly for all groups (1.6+/-0.8; p<0.001), as did heart failure hospitalizations (p<0.0001). Although all groups tolerated intensified heart failure therapy, only the young and middle-aged improved LV remodeling. However, older patients experienced equivalent significant improvements in heart failure symptoms and hospitalizations.

Reversal of heart failure remodeling in women

Epidemiological studies suggest that women with heart failure differ from men with heart failure in that their survival is better. Therapeutic trials have not clearly demonstrated a survival benefit for women. This study was to determine the tolerance for high doses of angiotensin-converting enzyme (ACE) inhibitor-nitrates in women versus men and to compare their symptomatic response, exercise tolerance, and ventricular functional improvement over 1 year. Eighty-eight sequential patients with heart failure, 54 men and 34 women with left ventricular ejection fraction < or = 35%, were prospectively followed for 1 year. For all patients, ACE inhibitor-nitrate therapy was intensified. Each patient had three 6-monthly echocardiograms at baseline, at 6 months, and at 1 year, and metabolic stress testing. Patients were 57.3 +/- 12.3 years old, with New York Heart Association (NYHA) class severity 2.6 +/- 1.0. Lisinopril dosages were raised from 14 +/- 14 mg/day to 57 +/- 26 mg/day, isosorbide mononitrate from 15 +/- 27 mg/day to 126 +/- 72 mg/day, and carvedilol (n = 34) to 17 +/- 16 mg/day. Women and men were epidemiologically comparable, with similar baseline echocardiographic parameters (left ventricular ejection fraction 19% +/- 7% versus 17% +/- 6%, respectively). Both tolerated up-titration in medical therapy. Final 12-month ejection fractions were equivalent for women and men at 34% +/- 17% and 34% +/- 13%, respectively, with similar improvements in left ventricular diameters. At 1 year, women had higher resting heart rates and remained more symptomatic with lower exercise capacity. However, the relative changes in NYHA status and aerobic capacity were similar for women and men. Thus, both women and men tolerated uptitrated ACE inhibitor-nitrate medical therapy, with comparable reversal of heart failure remodeling. Although women continued to be more symptomatic than men, relative improvements in symptomatic status, in exercise capacity, and in hospitalization rate were equivalent.

Ventricular unloading and myocyte recovery: insight gained into the pathophysiology of congestive heart failure

By unloading the failing myocardium and permitting tissue-based investigations before and after unloading, recent clinical use of ventricular assist devices (VADs) has provided a unique window into the pathophysiology of advanced heart failure in humans. Work to date has provided novel insights into the load-dependent modulation of myocardial hypertrophy, contractility, calcium homeostasis, adrenergic responsiveness, bioenergetics, cytokines, and gene expression. In general, the documented effects of VAD support on the failing heart have been diverse and often dramatic. Moreover, the phenotypic shifts observed have typically tended toward a less pathologic state than that associated with the refractory hypertrophy and heart failure that necessitated VAD implantation. The most striking feature of the composite body of work thus far accumulated in this area is the demonstration that even the most diseased human hearts exhibit the capacity for profound phenotypic plasticity when subjected to sufficient reductions in cardiac loading conditions and neurohormonal stimulation.

Left ventricular quantification in heart failure by cardiovascular MR using prospective respiratory navigator gating: comparison with breath-hold acquisition

Cardiovascular magnetic resonance (CMR) is the reference standard for the assessment of cardiac function. Faster sequences, such as breath-hold (BH) fast low-angle shot, have made CMR more clinically acceptable and cost effective. In a significantly large patient group, however, holding their breath is difficult, resulting in poor-quality images. We compared prospective navigator-echo respiratory gating (NE), which allows image acquisition during free breathing, and BH imaging in 14 patients with heart failure and 10 normal volunteers. There was good agreement between both NE and BH volumes, mass, and ejection fraction. The image quality of both NE basal and apical slices was significantly better than the corresponding BH slices in both the heart failure (P < 0.01) and normal groups (P < 0.05). The NE image acquisition was more time efficient than the BH acquisition in the heart failure group (P < 0. 01), with no difference in the normal group (P = 0.2). Thus, prospective navigator-echo gating, previously only described in coronary artery imaging, can be used in the assessment of cardiac function. It is particularly useful in patients who find it difficult to hold their breath in whom NE provides good-quality, time-efficient images.

The role of organic nitrates in the treatment of heart failure

Nitrates have been widely used in the treatment of patients with chronic congestive heart failure. Although the use of these drugs has not been approved by the Food and Drug Administration, multiple studies have shown their favorable effects. Organic nitrates have been shown to have a beneficial effect on ischemia, hemodynamic profile, magnitude of a mitral regurgitation, endothelial function, and cardiac remodeling. These drugs, when used in combination with hydralazine, have improved exercise capacity and survival. Recent studies have shown that the use of nitrates in patients already treated with standard heart failure therapy, including angiotensin converting enzyme (ACE) inhibitors, resulted in hemodynamic improvement, marked enhancement of exercise tolerance, reduction of left ventricular size, and augmentation of systolic function. These data suggest a role for organic nitrates as an adjunctive therapy to ACE inhibitors in patients with chronic heart failure and for nitrates in combination with hydralazine as an alternative treatment in patients who are intolerant to ACE inhibitors.

Effects of high-dose lisinopril-isosorbide dinitrate on severe mitral regurgitation and heart failure remodeling

In long-term, 1-year follow-up, uptitration of angiotensin-converting enzyme inhibitor and nitrate therapy over established doses can further improve severe functional mitral regurgitation in patients with dilated cardiomyopathy due to a reversal of heart failure-related left ventricular remodeling. With marked left ventricular enlargement, >6.8 cm end-diastolic diameter, heart failure remodeling may be irreversible and resistant to further medical intervention.