Review of Vasodilators in Acute Decompensated Heart Failure: The Old and the New

Acute Heart Failure: Diagnostic-Therapeutic Pathways and Preventive Strategies-A Real-World Clinician's Guide

Acute heart failure (AHF) is the most frequent cause of unplanned hospital admission in patients of >65 years of age and it is associated with significantly increased morbidity, mortality, and healthcare costs. Different AHF classification criteria have been proposed, mainly reflecting the clinical heterogeneity of the syndrome. Regardless of the underlying mechanism, peripheral and/or pulmonary congestion is present in the vast majority of cases. Furthermore, a marked reduction in cardiac output with peripheral hypoperfusion may occur in most severe cases. Diagnosis is made on the basis of signs and symptoms, laboratory, and non-invasive tests. After exclusion of reversible causes, AHF therapeutic interventions mainly consist of intravenous (IV) diuretics and/or vasodilators, tailored according to the initial hemodynamic status with the addition of inotropes/vasopressors and mechanical circulatory support if needed. The aim of this review is to discuss current concepts on the diagnosis and management of AHF in order to guide daily clinical practice and to underline the unmet needs. Preventive strategies are also discussed.

Current state and future perspective of cardiovascular medicines derived from natural products

The contribution of natural products (NPs) to cardiovascular medicine has been extensively documented, and many have been used for centuries. Cardiovascular disease (CVD) is the leading cause of morbidity and mortality worldwide. Over the past 40 years, approximately 50% of newly developed cardiovascular drugs were based on NPs, suggesting that NPs provide essential skeletal structures for the discovery of novel medicines. After a period of lower productivity since the 1990s, NPs have recently regained scientific and commercial attention, leveraging the wealth of knowledge provided by multi-omics, combinatorial biosynthesis, synthetic biology, integrative pharmacology, analytical and computational technologies. In addition, as a crucial part of complementary and alternative medicine, Traditional Chinese Medicine has increasingly drawn attention as an important source of NPs for cardiovascular drug discovery. Given their structural diversity and biological activity NPs are one of the most valuable sources of drugs and drug leads. In this review, we briefly described the characteristics and classification of NPs in CVDs. Then, we provide an up to date summary on the therapeutic potential and the underlying mechanisms of action of NPs in CVDs, and the current view and future prospect of developing safer and more effective cardiovascular drugs based on NPs.

Antihypertensive potential of cis-[Ru(bpy)2(ImN)(NO)]3+, a ruthenium-based nitric oxide donor

The aim of this study was to investigate the antihypertensive properties of cis-[Ru(bpy)₂ImN(NO)]³⁺ (FOR0811) in normotensive and in N^ω-nitro-L-arginine methyl ester (L-NAME)-induced hypertensive rats. Vasorelaxant effects were analyzed by performing concentration response curve to FOR0811 in rat aortic rings in the absence or presence of 1H-[1,2,4]-oxadiazolo-[4,3,-a]quinoxalin-1-one (ODQ), L-cysteine or hydroxocobalamin. Normotensive and L-NAME-hypertensive rats were treated with FOR0811 and the effects in blood pressure and heart rate variability in the frequency domain (HRV) were followed. FOR0811 induced relaxation in rat aortic rings. Neither endothelium removal nor L-cysteine altered the FOR0811 effects. However, the incubation with ODQ and hydroxocobalamin completely blunted FOR0811 effects. FOR0811 administered intravenously by bolus infusion (0.01-1 mg/bolus) or chronically by using subcutaneous implanted osmotic pumps significantly reduced the mean arterial blood pressure. The effect was long lasting and did not induce reflex tachycardia. FOR0811 prevented both LF and VLF increases in L-NAME hypertensive rats and has antihypertensive properties. This new ruthenium complex compound might be a promising nitric oxide donor to treat cardiovascular diseases.

Treatment of Congestive Heart Failure with Intravenous Nitroglycerin in Three Dogs with Degenerative Valvular Disease

We described the use of IV nitroglycerin as adjunctive therapy in three canine patients with left congestive heart failure secondary to degenerative mitral valve disease. All three dogs were admitted for signs of respiratory distress and all were determined to be in left congestive heart failure by history, exam findings, thoracic radiographs, and echocardiography. In addition to standard therapy for left congestive heart failure, IV nitroglycerin was administered as a constant rate infusion at a dose of 1-6 mcg/kg/min. No adverse events attributable to the drug were noted. This is the first reported use of IV nitroglycerin in clinical veterinary patients. Further studies are warranted to investigate the safety, efficacy, and optimal dosing of IV nitroglycerin infusions in dogs with left congestive heart failure.

A novel soluble guanylate cyclase activator with reduced risk of hypotension by short-acting vasodilation

Cinaciguat, a soluble guanylate cyclase (sGC) activator, was under clinical development for use in acute decompensated heart failure (ADHF), but was discontinued due to occurrence of hypotension. We hypothesized that short-term activation of sGC in ADHF patients would exert a vasodilative effect without hypotension irrespective of disease state, using a novel short-acting sGC activator, TY-55002. The objective of this study was to investigate the vasodilation and hemodynamic effects of TY-55002 in comparison with those of cinaciguat. TY-55002 and cinaciguat activated both normal and heme-oxidized sGC in a dose-dependent manner and caused rapid relaxation of phenylephrine-contracted rat aorta. However, TY-55002 had a milder effect than cinaciguat in enhancing the dose-activity response between normal and oxidized sGC. Therefore, we suggest that the pharmacological effect of TY-55002 is less subject than cinaciguat to oxidative stress associated with complications such as cardiovascular disease or diabetes. In normal dogs, the effects of intravenous TY-55002 or cinaciguat on blood pressure were evaluated in conjunction with the plasma concentrations of the compounds, and pharmacokinetic (PK)-pharmacodynamic (PD) analyses were carried out. The plasma-to-effect-site transfer rate constant (Ke0) for TY-55002 was three times greater than for cinaciguat. On the other hand, there was a small difference in blood half-life (T1/2) between the compounds. It is possible that the rapid fall in blood pressure after the initial administration of TY-55002 and the quick recovery after cessation were due to the pharmacodynamic property of the compound. In heart failure-model dogs, TY-55002 and cinaciguat improved the condition to the same degree, and the short-term action of TY-55002 was replicated. In conclusion, TY-55002 is a novel short-acting sGC activator, which offers the possibility of easy dose management without excessive hypotension. It therefore holds potential to serve as an innovative drug in the pharmacotherapy of ADHF.

Efficacy and Safety of Intravenous Urapidil for Older Hypertensive Patients with Acute Heart Failure: A Multicenter Randomized Controlled Trial

PURPOSE

Urapidil is putatively effective for patients with hypertension and acute heart failure, although randomized controlled trials thereon are lacking. We investigated the efficacy and safety of intravenous urapidil relative to that of nitroglycerin in older patients with hypertension and heart failure in a randomized controlled trial.

MATERIALS AND METHODS

Patients (>60 y) with hypertension and heart failure were randomly assigned to receive intravenous urapidil (n=89) or nitroglycerin (n=91) for 7 days. Hemodynamic parameters, cardiac function, and safety outcomes were compared.

RESULTS

Patients in the urapidil group had significantly lower mean systolic blood pressure (110.1±6.5 mm Hg) than those given nitroglycerin (126.4±8.1 mm Hg, p=0.022), without changes in heart rate. Urapidil was associated with improved cardiac function as reflected by lower N terminal-pro B type natriuretic peptide after 7 days (3311.4±546.1 ng/mL vs. 4879.1±325.7 ng/mL, p=0.027) and improved left ventricular ejection fraction (62.2±3.4% vs. 51.0±2.4%, p=0.032). Patients given urapidil had fewer associated adverse events, specifically headache (p=0.025) and tachycardia (p=0.004). The one-month rehospitalization and all-cause mortality rates were similar.

CONCLUSION

Intravenous administration of urapidil, compared with nitroglycerin, was associated with better control of blood pressure and preserved cardiac function, as well as fewer adverse events, for elderly patients with hypertension and acute heart failure.

Effects of vasodilator and esmolol-induced hemodynamic stability on early post-operative cognitive dysfunction in elderly patients: a randomized trial

OBJECTIVE

To investigate the effect of continuous intravenous injection of nicardipine and/or nitroglycerin with or without esmolol on the occurrence of early post-operative cognitive dysfunction (POCD) in elderly patients.

METHODS

Elderly patients (n=340) who underwent radiofrequency ablation for atrial fibrillation were randomized into five groups: A, nicardipine; B nicardipine+esmolol; C, (nitroglycerin) group; D nitroglycerin+esmolol; E (control) groups. The hemodynamic parameters were recorded, and Mini Mental State Examination was used to assess cognitive function.

RESULTS

At 30 min and 60 minutes after anesthesia and at the conclusion of surgery, the rate pressure product value was significantly lower in Groups B (10621.1±321.7, 10544.2±321.8, and 10701.3±325.5, respectively) and D (10807.4±351.1, 10784.3±360.3, and 10771.7±345.7, respectively) than in Group E (13217.1±377.6, 13203.5±357.3, and 13119.2±379.5, respectively). The heart rate was significantly higher in Groups A (104.1±10.3, 104.9±11.1, and 103.9±11.8, respectively) and C (103.7±11.3, 105.5±10.5, and 107.7±11.7, respectively) than in Group E (89.3±12.0, 88.5±11.5, and 85.5±11.6, respectively). The incidence of POCD was significantly lower in Groups A and B than in Groups C, D, and E. Univariate regression analysis showed that regimens in Groups A, B, and E and doses of propofol and fentanyl were risk factors for POCD. Multivariate logistic regression analysis revealed significant associations between the incidence of POCD and interventions in Groups A and B.

CONCLUSION

Maintenance of stable intraoperative hemodynamics using nicardipine and nitroglycerin or their combinations with esmolol, especially nicardipine with esmolol, reduced the incidence of POCD in the elderly with potential cardiovascular diseases.

Therapeutic effects of intravenous urapidil in elderly patients with hypertension and acute decompensated heart failure: A pilot clinical trial

Urapidil has been proposed to be an effective vasodilator for the treatment of acute decompensated heart failure (ADHF); however, its effect on cardiac function, as compared with that of nitroglycerin, in elderly patients with hypertension and ADHF has yet to be determined. In the present study, a multicenter, open-label clinical trial was performed, in which 120 elderly patients with hypertension and ADHF were randomly assigned to the treatment (50–400 µg/min intravenous urapidil) or control group (5–40 µg/min intravenous nitroglycerin). The dosages of the medications were adjusted according to the blood pressure of the patients. The systolic and diastolic blood pressure, heart rate and serum level of N-terminal pro B-type natriuretic peptide (NT-proBNP) were evaluated at hospital admission and at days 1, 2, 3 and 7 after treatment. In addition, the left ventricular function was assessed by measuring the left ventricular ejection fraction (LVEF) and left ventricular end-diastolic volume at hospital admission and at days 2 and 7 after treatment. The results indicated that intravenous administration of urapidil and nitroglycerin were effective in lowering the blood pressure and heart rate within 7 days, with no significant differences observed between the two groups (P>0.05). By contrast, greater reduction in the serum NT-proBNP level (2,410.4±546.1 vs. 4,234.1±876.4 pg/ml; P<0.05) and greater improvement in the LVEF (55.3±3.4 vs. 45.2±2.4%; P<0.05) were observed in the urapidil-treated group, as compared with the nitroglycerin-treated group. No adverse events were reported during the treatment period in the two groups. The clinical outcomes at 6 months following discharge were evaluated and were not found to be significantly different between the two groups. In conclusion, the present results of the present study suggested that urapidil was as effective as nitroglycerin in controlling blood pressure and heart rate and was more effective in improving cardiac systolic function in elderly patients with hypertension and ADHF.

A multicenter, randomized, trial comparing urapidil and nitroglycerin in multifactor heart failure in the elderly

BACKGROUND

Multifactor heart failure is a common life-threatening event in elderly patients and often complicated by concomitant hypertension and diabetes mellitus (DM). The aim of this study was to evaluate whether α1-blocker, urapidil, provides additional therapeutic benefits compared to nitroglycerin (NG) in treatment of multifactor heart failure complicated by hypertension and DM in elderly patients.

METHODS

Seventy-two elderly consecutive patients were randomized into 2 groups that received treatment with urapidil or NG. All patients were monitored for blood pressure (BP) and heart rate and received tests for metabolic activity and cardiovascular function.

RESULTS

Patients receiving urapidil had significantly lower systolic BP than their counterparts in NG group (P < 0.05). Moreover, patients in urapidil group showed lower N-terminal pro-B-type natriuretic peptide levels but higher ejection fraction (t = 2.206, P < 0.05), cardiac index (t = 3.13, P < 0.05) and left end-diastolic volume (t = -3.104, P < 0.05) compared to NG group. Although both urapidil and NG decreased fasting plasma glucose (FPG) levels, there was no significant difference of FPG levels between these 2 groups.

CONCLUSIONS

Urapidil demonstrated better efficacy than NG on lowering and stabilizing systolic BP, attenuating cardiac afterload and improving cardiac function. Both NG and urapidil significantly reduced FPG levels in multifactor heart failure patients with DM. Urapidil is a therapeutic option for the multifactor heart failure patients complicated with hypertension and DM.

Lack of evidence for intravenous vasodilators in ED patients with acute heart failure: a systematic review

There are nearly 700,000 annual US emergency department (ED) visits for acute heart failure (AHF). Although blood pressure is elevated on most of these visits, acute therapy remains focused on preload and not afterload reduction. Data from recent prospective studies suggest that patients with AHF with concomitant acute hypertension benefit from intravenous (IV) vasodilators. To better understand the use of vasodilators for such patients, we conducted a systematic review of (1) currently available intravenous vasodilators for ED patients with AHF, or (2) intravenous vasodilators that are not yet available, but have completed phase III clinical trials in AHF, and may be available for ED use in the future. We used multiterm search queries to retrieve research involving nitroglycerin, nitroprusside, enalaprilat, hydralazine, relaxin, and nesiritide. A total of 2001 unique citations were identified from 3 databases: PubMed, EMBASE, and CINAHL. Of these, 1966 were excluded on the basis of established review criteria, leaving 35 published articles for inclusion. Our primary finding was that intravenous nitrovasodilators, when used in the treatment of AHF in ED and ED-like settings, do improve short-term symptoms and appear safe to administer. There are no data suggesting that they impact mortality. Other commonly used vasodilators such as hydralazine and enalaprilat have very little published data about their safety and efficacy. Of note, few studies enrolled patients early in their course of treatment. Thus, to assess the specific impact of vasodilator therapy on both short- and long-term outcomes, future research efforts should focus on patient recruitment in the ED setting.

Low-dose B-type natriuretic peptide raises cardiac sympathetic nerve activity in sheep

The reported effects of atrial natriuretic peptide (ANP) on sympathetic nerve activity (SNA) are variable, dependent on concomitant hemodynamic actions, and likely to be regionally differentiated. There are few reports of the effect of B-type natriuretic peptide (BNP) on SNA and none have measured cardiac SNA (CSNA) by direct microneurography. We measured the effects of low-dose ANP and BNP (2.4 pmol·kg−1·min−1 infused for 120 min) on CSNA and hemodynamics in conscious sheep ( n = 8). While there was a trend for mean arterial pressure and cardiac output to fall with both ANP and BNP, changes were not significant compared with vehicle control. However, BNP did significantly reduce systolic arterial (97 ± 4.2 vs. 107 ± 6.8 mmHg during control; P = 0.043) and pulse pressures (0.047) and increase heart rate (110 ± 6.7 vs. 96 ± 7.3 beats/min; P = 0.044). Trends for these hemodynamic parameters to change with ANP did not achieve statistical significance. ANP also had no significant effect on any CSNA parameters measured. In contrast, BNP induced a rise in both CSNA burst frequency (∼20 bursts/min higher than control, P = 0.011) and burst area (∼40% higher than control, P = 0.013). BNP-induced rises in burst incidence (bursts/100 beats), and burst area per 100 beats, however, were not significant. In conclusion, BNP infused at low doses that only had subtle effects on hemodynamics increased CSNA burst frequency and burst are per minute. This increase in CSNA may in large part be secondary to an increase in heart rate as CSNA burst incidence and burst area per 100 beats were not significantly increased. This study provides no evidence for inhibition of CSNA by natriuretic peptides.

The Valsalva maneuver can misdiagnose 'normal' as 'pseudonormal': a word of caution for an echocardiographic evaluation of diastolic function

OBJECTIVES

To identify differences in cardiac hemodynamic changes between the Valsalva maneuver and nitroglycerin (NTG) administration.

METHODS

Fifty-three subjects (37 men, 43 ± 12 years) with normal cardiac function [left ventricular ejection fraction ≥55%, early to late mitral inflow velocity ratio (E/A) ≥1, left atrial volume index ≤34 ml/m(2) and early diastolic mitral annulus velocity (E') ≥8 cm/s] were enrolled. Doppler parameters were determined at rest, during the Valsalva maneuver and after NTG administration.

RESULTS

Decreased E, A and E/A were observed both during the Valsalva maneuver and after NTG administration (p < 0.0001 for all). However, the reduction in E (ΔEValsalva: -30 ± 16 cm/s vs. ΔENTG: -17 ± 17 cm/s) and E/A (ΔE/AValsalva: -0.37 ± 0.28 vs. ΔE/ANTG: -0.19 ± 0.25) and the prolongation of the deceleration time (DT) of E (ΔDTValsalva: 105 ± 74 ms vs. ΔDTNTG: 83 ± 63 ms) were more prominent during the Valsalva maneuver than with NTG administration (p < 0.0001 for all). Particularly, a greater decrease in E' was observed during the Valsalva maneuver (ΔE'Valsalva: -3 ± 2 cm/s vs. ΔE'NTG: -2 ± 2 cm/s, p < 0.0001). Eighteen subjects (34%) showed ΔE/A ≥0.5 during the Valsalva maneuver; thus, they were mislabeled as 'pseudonormal', while only 3 subjects (6%) showed ΔE/A ≥0.5 after NTG administration.

CONCLUSIONS

The Valsalva maneuver not only decreases preload but also affects myocardial performance, thus, its use can result in the mislabeling of normal subjects as pseudonormal.

Enhancing vascular relaxing effects of nitric oxide-donor ruthenium complexes

Ruthenium-derived complexes have emerged as new nitric oxide (NO) donors that may help circumvent the NO deficiency that impairs vasodilation. NO in vessels can be produced by the endothelial cells and/or released by NO donors. NO interacts with soluble guanylyl-cyclase to produce cGMP to activate the kinase-G pathway. As a result, conductance arteries, veins and resistance arteries dilate, whereas the cytosolic Ca2+ levels in the smooth muscle cells decrease. NO also reacts with oxygen or the superoxide anion, to generate reactive oxygen species that modulate NO-induced vasodilation. In this article, we focus on NO production by NO synthase and discuss the vascular changes taking place during hypertension originating from endothelial dysfunction. We will describe how the NO released from ruthenium-derived complexes enhances the vascular effects arising from failed NO generation or lack of NO bioavailability. In addition, how ruthenium-derived NO donors induce the hypotensive effect by vasodilation is also discussed.

Congestive heart failure: experimental model

INTRODUCTION

Surgically induced, combined volume and pressure overload has been used in rabbits to create a simplified and reproducible model of acute left ventricular (LV) failure.

MATERIALS AND METHODS

New Zealand white male rabbits (n = 24, mean weight 3.1 ± 0.2 kg) were randomly assigned to either the Control group (n = 10) or to the Heart Failure group (HF, n = 14). Animals in the Control group underwent "sham" procedures. Animals in the HF group underwent procedures to induce LV volume overload by inducing severe aortic valve regurgitation with aortic cusp disruption and pressure overload using an occlusive silver clip positioned around the pre-renal abdominal aorta.

RESULTS

Following Procedure-1 (volume overload) echocardiography confirmed severe aortic regurgitation in all animals in the HF group, with increased mean pulse pressure difference from 18 ± 3 to 38 ± 3 mmHg (P < 0.0001). After Procedure-2 (pressure overload) all animals in the HF group showed clinical and echocardiographic signs of constriction of the abdominal aorta and echocardiography confirmed progressively declining LV function. At the end of the protocol there was a significant increase of the heart/body weight ratio in the HF group vs. Control group (4.6 ± 0.2 vs. 2.9 ± 0.1 g/kg, P < 0.05), and echocardiography showed in HF group significant increase of the LV end-diastolic diameter (2.15 ± 0.09 vs. 1.49 ± 0.03 cm, P < 0.001) and reduction of the LV shortening fraction (26.3 ± 3.8 vs. 41.3 ± 1.6%, P < 0.001).

CONCLUSION

This experimental model: (a) consistently produces LV hypertrophy/dilatation and subsequent congestive heart failure, (b) provides new data on the time course of LV dilatation, hypertrophy and failure, (c) allows study of the progress and evolution of LV systolic and diastolic dysfunction in the presence of induced LV failure, (d) is suitable to study intervention or pharmacological administration to reduce the negative effects of acute LV failure.