Comparison of the effects of dobutamine and nesiritide (B-type natriuretic peptide) on ventricular ectopy in acutely decompensated ischemic versus nonischemic cardiomyopathy

Effects of Recombinant Human Brain Natriuretic Peptide on Atrial Fibrillation After Coronary Artery Bypass Grafting

ABSTRACT

Previous studies reported that the use of natriuretic peptides (NPs) can effectively decrease arrhythmias. However, there is a lack of clinical evidence that recombinant human brain natriuretic peptide (rh-BNP) inhibits postoperative atrial fibrillation (POAF). This cohort aims to assess the effect of rh-BNP on POAF. This study retrospectively reviewed patients who underwent isolated coronary artery bypass grafting from January 2018 to January 2021. Patients were divided into 2 groups according to whether they received rh-BNP therapy within 5 days after surgery. A total of 1153 patients met the inclusion and exclusion criteria, of which 54 received rh-BNP therapy within 5 days. After propensity score matching, 53 patients were treated with rh-BNP, and 148 patients were not treated with rh-BNP. The incidence of POAF was lower in rh-BNP group than non-rh-BNP group (18.9% vs. 37.2%, odds ratio = 0.393, 95% confidence interval, 0.183-0.845, P = 0.017). There was no significant difference in the occurrence of ventricular arrhythmia ( P = 0.4), hypotension ( P = 0.763), and the risk of death ( P = 0.14). rh-BNP could significantly reduce the occurrence of POAF after coronary artery bypass grafting, and rh-BNP did not increase the risk of ventricular arrhythmia, hypotension, and death. Accordingly, rh-BNP could be a potential safe medicine for preventing POAF.

Acute heart failure: lessons learned so far

Acute heart failure (AHF) affects nearly every Canadian with heart failure (HF) at least once. Despite several attempts, no medical therapies have been shown to improve the natural history of AHF. In addition, the place of diagnosis of AHF is increasingly made in the outpatient setting. In this view, AHF is a moving target, and from recent registry data and from clinical trials, 5 critical lessons regarding the syndrome of AHF emerge: (1) The period of clinical instability preceding AHF may be much longer than previously thought. (2) Refinement of tools used to aid the early and accurate diagnosis of AHF will impact patient outcomes. (3) Standard supportive care of patients with AHF includes early use of diuretics with frequent reassessment in nearly all patients and supplemental vasodilators and oxygen therapy in selected cases. (4) Patients who survive presentation of AHF continue to suffer high rates of re-presentation, death, and rehospitalization following discharge from either hospital or emergency department. (5) Interventions shown to improve patient outcomes for AHF to date are related to process of care rather than new medications or devices. This report reviews the recent literature regarding the presentation, diagnosis, management, and prognosis of AHF. Areas of future research priority are indicated and guidelines for improving treatment are provided. AHF is an important clinical area that has not been as intensively studied as chronic HF; it presents both important needs and exciting opportunities for research and innovation.

Current treatment options for early management in acute decompensated heart failure

Acute decompensated heart failure (ADHF) is a common syndrome that precedes over 100,000 hospitalizations in Canada per year (with length of stay in excess of six to eight days), making this the most costly disorder for patients older than 65 years of age. Over 85% of ADHF patients present with shortness of breath and exhibit evidence of volume overload. These findings may be variable in elderly patients, which complicates diagnosis. In fact, even in experienced centres, diagnostic accuracy is less than 80%. Despite advances in the treatment of chronic heart failure, meaningful improvements in outcomes associated with ADHF are very few. The basic assessment and treatments have not changed (early parenteral diuretics, electrocardiographic and oxygen saturation monitoring, supplemental oxygen administration). The introduction of measurement of natriuretic peptides in those in whom the diagnosis is uncertain may reduced the error rate by over 50%. The use of vasodilator therapy in the absence of cardiogenic shock can lead to earlier amelioration of symptoms, especially in those who do not respond to initial diuretics. Repeated monitoring of vital signs, body weight, electrolytes and creatinine levels is essential to minimize the risk of side effects of treatments. Noninvasive ventilation may reduce the need for endotracheal intubation in patients with severe ADHF and hypoxia at rest. Once the initial phase of heart failure treatment is completed, then the clinician should begin to focus on maximization of chronic heart failure therapy and discharge planning.

Benefit-Risk Assessment of Nesiritide in the Treatment of Acute Decompensated Heart Failure

Nesiritide is a recombinant form of human B-type natriuretic peptide, a naturally occurring endogenous hormone released by cardiac ventricles in response to an increase in ventricular wall stress. Its use in the treatment of acute decompensated heart failure (ADHF) has been evaluated in a series of randomised controlled clinical trials. It is currently approved in the US for the treatment of ADHF. Nesiritide induces a balanced vasodilation and an indirect increase in cardiac output, but has no actual inotropic effects and exerts a neutral effect on heart rate. In addition, it inhibits adverse neurohormonal activation and, in some individuals, promotes natriuresis and diuresis. In adults with ADHF, nesiritide reduces pulmonary capillary wedge pressure, right atrial pressure and systemic vascular resistance; decreases symptoms of heart failure; and enhances global clinical status. Important questions regarding the risks of nesiritide therapy have recently been raised, and resolution of the safety of nesiritide is a process that remains in evolution. The most frequently reported adverse effect is dose-related hypotension. In addition, nesiritide may cause an acute increase in serum creatinine concentration. This increase seems to be a haemodynamic response to a combination of volume depletion, vasodilation and neurohormonal inhibition. Nesiritide-induced changes in renal function have not been definitively shown to negatively affect mortality. The effect of nesiritide on all-cause mortality is currently unresolved. Recent meta-analyses of existing databases have raised concerns regarding adverse effects of the drug on 30-day mortality. However, reviews of large, observational, registry databases do not suggest an adverse inpatient mortality effect compared with other vasodilator therapies. Further resolution of the mortality question awaits completion of pending randomised controlled clinical trials. When used for approved indications and according to recommended dosage and administration regimens, nesiritide represents a reasonable treatment adjunct for ADHF.

Nesiritide in cardiovascular anesthesia

PURPOSE OF REVIEW

Acute heart failure has become a major medical issue in the western population. Because mortality is still as high as 50%, the treatment of these patients has been the focus of many studies. A new approach has recently been proposed, including B-type natriuretic peptide as a medication. The purpose of this review is to discuss these new developments.

RECENT FINDINGS

Recent studies have shown that plasma levels of B-type natriuretic peptide may serve as a marker for the severity of acute decompensated heart failure. Nesiritide, which is the recombinant equivalent of B-type natriuretic peptide, is a vasodilator, acting by increasing cyclic guanosine 3', 5'-monophosphate in the vascular smooth muscle cells. It is mainly considered to be an alternative for nitroglycerin, because it has fewer side-effects, and its activity is more prolonged. Treatment with nesiritide has shown fewer arrhythmias and a lower mortality rate compared with dobutamine and milrinone. In cardiac surgery, nesiritide is mainly administered to patients awaiting heart transplantation, but intraoperatively the doses of nesiritide and anesthetics must be adjusted because of a potential interaction. A few anecdotal reports have shown the advantageous effects of nesiritide in the early post-bypass period.

SUMMARY

Anesthesiologists will be confronted with increasing numbers of patients with heart failure, who require new forms of medication. Nesiritide is a promising new tool, and its application, which is still mainly restricted to the preoperative period, will probably soon be extended to the early post-bypass period.

Inhibition of aldosterone and endothelin-1 by carperitide was attenuated with more than 1 week of infusion in patients with congestive heart failure

Short-term infusion of carperitide (atrial natriuretic peptide) has beneficial effects on neurohumoral factors; however, it remains unclear whether the effects are sustained for long-term infusion. To evaluate the effects of long-term infusion of carperitide on neurohumoral factors in patients with chronic congestive heart failure (CHF), we measured neurohumoral factors before and 1 hour after stopping carperitide infusion in 42 CHF patients. Carperitide infusion was continued for more than 2 days until there was symptomatic improvement of CHF. Patients were divided into 2 groups by the median value of infusion duration: group 1 (less than 7 days, n=21) and group 2 (more than 7 days, n=21). In group 1, aldosterone (ALD) and endothelin-1 (ET-1) were significantly increased after stopping carperitide. In contrast, ALD and ET-1 did not change after stopping carperitide in group 2. The molar ratio of cyclic guanosine monophosphate/atrial natriuretic peptide before stopping carperitide was significantly lower in group 2 than in group 1. Suppression of ALD and ET-1 was maintained for 7 days of carperitide infusion, but the beneficial effect on neurohumoral factors was attenuated after more than 7 days, probably through down-regulation of biologic receptors coupled with guanylate cyclase in CHF patients.

Pulmonary Hemodynamic Responses to Brain Natriuretic Peptide and Sildenafil in Patients With Pulmonary Arterial Hypertension

STUDY OBJECTIVES

Brain natriuretic peptide (BNP) blunts hypoxic pulmonary hypertension in animal models, but its acute hemodynamic effects in patients with pulmonary arterial hypertension (PAH) are not known. The aim of this study was to determine if human B-type natriuretic peptide is a safe and efficacious pulmonary vasodilator in patients with PAH and if the pulmonary hemodynamic effects are potentiated by phosphodiesterase inhibition.

DESIGN

Open-label study.

SETTING

Medical ICUs of three tertiary care hospitals in New England.

PATIENTS

Thirteen consecutive adult patients undergoing right-heart catheterization and a pulmonary vasodilator trial for the initial evaluation of PAH.

INTERVENTIONS

Patients were administered inhaled nitric oxide (iNO), i.v. epoprostenol, and a 3-h infusion of BNP alone and 1 h after an oral dose of the phosphodiesterase-5 inhibitor sildenafil.

RESULTS

iNO and sildenafil alone decreased mean pulmonary artery pressure (mPAP) without a significant fall in pulmonary vascular resistance (PVR). Epoprostenol decreased both mPAP and PVR. BNP alone had no significant effect on pulmonary hemodynamics, but the combination of sildenafil plus BNP decreased mPAP and PVR for up to 6 h after stopping BNP. The decrease in mPAP with sildenafil plus BNP (+/- SE) was greater than after 1 h of sildenafil alone (44.6 +/- 3.8 to 40.6 +/- 3.9 mm Hg, p = 0.027). An acute vasodilator response, defined as a decrease in mPAP > 10 mm Hg and end mPAP < 40 mm Hg, was seen in 0 of 8 patients with iNO, 1 of 13 patients with epoprostenol, 0 of 13 patients with BNP, and 4 of 12 patients with sildenafil plus BNP. BNP decreased mean systemic arterial pressure (5.6 +/- 2.8 mm Hg) but had no effect on cardiac output or systemic vascular resistance.

CONCLUSIONS

A 3-h BNP infusion does not significantly improve pulmonary hemodynamics in most patients with PAH but is well tolerated and augments the acute pulmonary vasodilator effect of sildenafil.

Overview of randomized clinical trials in acute heart failure syndromes

Acute heart failure syndromes (AHFS) are among the most frequent causes of hospitalizations in the United States and Europe. Despite current therapies, patients with AHFS have high readmission and mortality rates. The randomized, controlled clinical trial is the standard by which contemporary therapies are evaluated, yet this tool of clinical science only recently has been rigorously applied to the development of novel therapies for patients with AHFS. This review briefly discusses some of the challenges presented in designing a clinical trial of therapies for AHFS and to describe some of the recent trials with respect to these issues in established drugs (such as milrinone, dobutamine, nitroglycerin, nitroprusside, and nesiritide) that have been approved by the US Food and Drug Administration (FDA). Recent trials of current investigational agents, such as levosimendan (the Randomized Multicenter Evaluation of Intravenous Levosimendan Efficacy Versus Placebo in the Short-Term Treatment of Decompensated Heart Failure [REVIVE], the Calcium Sensitizer or Inotrope or None in Low-Output Heart Failure [CASINO] study, and the Survival of Patients with Acute Heart Failure in Need of Intravenous Inotropic Support [SURVIVE] trial), tezosentan (the Randomized Intravenous Tezosentan [RITZ] study and the Value of Endothelin Receptor Inhibition with Tezosentan in Acute Heart Failure Studies [VERITAS]), and tolvaptan (the Acute and Chronic Therapeutic Impact of a Vasopressin Antagonist in Congestive Heart Failure [ACTIV-CHF] study), are also discussed.

Decompensated Heart Failure: Is There a Role for the Outpatient Use of Nesiritide?

Heart failure (HF) management has seen enormous advances in the past two decades, including publication of HF management guidelines targeted at further reduction of morbidity and mortality. Nonetheless, the morbidity of HF has steadily increased and now represents one of the largest health care expenditures in this country. Because hospitalization for HF is most likely for patients with more advanced HF, they share a disproportionate burden of the hospitalization costs and will require treatment regimens beyond the current guidelines, if this burden is to be alleviated. In June 2004, a group of investigators who helped establish the natriuretic peptide treatment paradigm, met to discuss the potential role of nesiritide as an outpatient treatment option for patients with symptomatic HF who were at high risk for repeated admissions, a syndrome now described as "chronic decompensated HF." This report presents their considerations on the contribution of natriuretic peptide physiology to the amelioration of progressive left ventricular dysfunction, the therapeutic use of B-type natriuretic peptide, and its potential application to the outpatient management of acute and chronic decompensated HF. The use of outpatient IV nesiritide was considered a promising treatment option for symptomatic chronic decompensated HF patients that merits further investigation. Such an approach, once validated, should be integrated into an evidence-based HF disease management program.

A rational approach for the treatment of acute heart failure: current strategies and future options

PURPOSE OF REVIEW

Acute decompensated heart failure represents a major, growing health problem in the developed world. However, until recently, relatively little research has been performed in this field to provide a basis for rational treatment strategies. The purpose of this review is to discuss the current approach and the potential future strategies for treatment of patients with acute decompensated heart failure.

RECENT FINDINGS

Recent data have confirmed the heterogeneous nature of patients admitted with acute decompensated heart failure, and the limitations of the current therapeutic regimens with diuretics, intravenous vasodilators (ie, nitroglycerin, nitroprusside), and intravenous inotropes (ie, dobutamine, milrinone). A new vasodilator, nesiritide, has been demonstrated to improve hemodynamics and symptoms at 3 hours compared with nitroglycerin, and has been added to the therapeutic armamentarium in the United States. However, none of these agents has been shown to influence patient outcomes favorably. Given the high readmission rates, morbidity, and mortality of acute decompensated heart failure, other newer approaches, such as antagonists to a number of neurohumoral targets (ie, endothelin [tezosentan], vasopressin [conivaptan, tolvaptan], and adenosine) and non-cAMP-mediated inotropy (ie, levosimendan), are currently under investigation and showing promise.

SUMMARY

Acute decompensated heart failure presents a challenging therapeutic problem for clinicians. Although they readily correct the hemodynamic abnormalities, current treatment strategies have significant limitations and have not been shown to improve morbidity or mortality. A number of new agents are under investigation with the goal of improving patient outcomes.