Enalapril in congestive heart failure: acute and chronic invasive hemodynamic evaluation

Synthetic Transformation of 2-{2-Fluoro[1,1'-biphenyl]-4-yl} Propanoic Acid into Hydrazide-Hydrazone Derivatives: In Vitro Urease Inhibition and In Silico Study

In the present study, 28 acyl hydrazones (4-31) of flurbiprofen were synthesized in good to excellent yield by reacting different aromatic aldehydes with the commercially available drug flurbiprofen. The compounds were deduced with the help of different spectroscopic techniques like ¹H-NMR and HREI-MS and finally evaluated for in vitro urease inhibitory activity. All of the synthesized products demonstrated good inhibitory activities in the range of IC₅₀ = 18.92 ± 0.61 to 90.75 ± 7.71 μM as compared to standard thiourea (IC₅₀ = 21.14 ± 0.42 μM). Compound 30 was found to be the most active among the series better than the standard thiourea. A structure-activity relationship (SAR) study revealed that the presence of electron-donating groups on the phenyl ring plays a prominent role in the inhibition of the urease enzyme. Moreover, in silico molecular modeling analysis was carried out to study the effect of substituents in synthesized derivatives on the binding interactions with the urease enzyme.

Benefit from sacubitril/valsartan is associated with hemodynamic improvement in heart failure with reduced ejection fraction: An echocardiographic study

BACKGROUND

Sacubitril/valsartan improves outcome in patients with heart failure (HF) with reduced left ventricular (LV) ejection fraction (EF, HFrEF). However, little is known about possible mechanisms underlying this favourable effect.

PURPOSE

To assess changes in echocardiographically-derived hemodynamic profiles induced by sacubitril/valsartan and their impact on outcome.

METHODS

In this multicenter, open-label study, 727 HFrEF outpatients underwent comprehensive echocardiography at baseline (before starting sacubitril/valsartan) and after 12 months. Estimated LV filling pressure (E/e') and cardiac index (CI, l/min/m²) were combined to determine 4 hemodynamic profiles: profile-A (normal-flow/normal-pressure); profile-B (low-flow/normal-pressure); profile-C: (normal-flow/high-pressure); profile-D: (low-flow/high-pressure). Changes among categories were recorded, and their associations with rates of the composite of death/HF-hospitalization were assessed by multivariable Cox analysis.

RESULTS

At baseline, 29% had profile-A, 15% had profile-B, 32% profile-C, and 24% profile-D. After 12 months, the hemodynamic profile improved in 53% of patients (all profile-A achievers, or profile-D patients achieving either C or B profile), while it remained unchanged in 39% patients and worsened in 9%. Prevalence of improved profile progressively increased with increasing dose of sacubitril/valsartan (P < 0.0001). After the second echocardiography, patients were followed up 12.6 ± 7.6 months: event-rate was lower in patients with improved profile (12.3%, 95%CI: 9.4-16.1) compared to patients in whom hemodynamic profile remained unchanged (29.9%, 24.0-37.3) or worsened (31.2%, 20.7-46.9, P < 0.0001). Improved hemodynamic profile was associated with favourable outcome independent of LVEF and other covariates (HR 0.65, 95%CI: 0.45-0.95, P < 0.05).

CONCLUSION

In HFrEF patients, the beneficial prognostic effects of sacubitril/valsartan are associated with improvement in hemodynamic conditions.

Acute effects of angiotensin-converting enzyme inhibition versus angiotensin II receptor blockade on cardiac sympathetic activity in patients with heart failure

The beneficial effects of angiotensin-converting enzyme (ACE) inhibitors and angiotensin II (ANG II) receptor antagonists in patients with heart failure secondary to reduced ejection fraction (HFrEF) are felt to result from prevention of the adverse effects of ANG II on systemic afterload and renal homeostasis. However, ANG II can activate the sympathetic nervous system, and part of the beneficial effects of ACE inhibitors and ANG II antagonists may result from their ability to inhibit such activation. We examined the acute effects of the ACE inhibitor captopril (25 mg, n = 9) and the ANG II receptor antagonist losartan (50 mg, n = 10) on hemodynamics as well as total body and cardiac norepinephrine spillover in patients with chronic HFrEF. Hemodynamic and neurochemical measurements were made at baseline and at 1, 2, and 4 h after oral dosing. Administration of both drugs caused significant reductions in systemic arterial, cardiac filling, and pulmonary artery pressures (P < 0.05 vs. baseline). There was no significant difference in the magnitude of those hemodynamic effects. Plasma concentrations of ANG II were significantly decreased by captopril and increased by losartan (P < 0.05 vs. baseline for both). Total body sympathetic activity increased in response to both captopril and losartan (P < 0.05 vs. baseline for both); however, there was no change in cardiac sympathetic activity in response to either drug. The results of the present study do not support the hypothesis that the acute inhibition of the renin-angiotensin system has sympathoinhibitory effects in patients with chronic HFrEF.

A remarkable medical story: benefits of angiotensin-converting enzyme inhibitors in cardiac patients

The development of angiotensin-converting enzyme inhibitors (ACE inhibitors) has been one of the most remarkable stories in the treatment of cardiovascular diseases. Angiotensin converting enzyme inhibitors have several acute and sustained hemodynamic effects that are beneficial in the presence of left ventricular (LV) dysfunction. They increase cardiac output and stroke volume and reduce systemic vascular resistance as well as pulmonary capillary wedge pressure. The hemodynamic benefits are associated with improvement in the signs and symptoms of congestive heart failure (CHF) as well as decreased mortality, regardless of the severity of CHF. In patients with asymptomatic LV dysfunction, therapy with ACE inhibitors prevented the development of CHF and reduced hospitalization and cardiovascular death. They also increase survival when administered early after an acute myocardial infarction (MI). Most recently, ACE inhibition was associated with improved clinical outcomes in a broad spectrum of high-risk patients with preserved LV function. The mechanism of ACE inhibitors benefits is multifactorial and includes prevention of progressive LV remodeling, prevention of sudden death and arrhythmogenicity and structural stability of the atherosclerotic process. Evidence suggests that ACE inhibitors are underutilized in patients with cardiovascular diseases. Efforts should be directed to prescribe ACE inhibitors to appropriate patients in target doses. It is reasonable to believe that ACE inhibitors have a class effect in the management of LV dysfunction with or without CHF and acute MI. Whether the same is true for ACE inhibitors in the prevention of ischemic events is not known yet.

Angiotensin II receptor antagonists: the prototype losartan

OBJECTIVE

To describe a new class of antihypertensive agents, the angiotensin II receptor antagonists, with emphasis on the prototype losartan. Pharmacokinetic data and clinical trials are reviewed, as well as adverse reactions, drug interactions, and dosing guidelines.

DATA SOURCES

A MEDLINE search of English-language literature published from 1966 through 1995 was performed. In addition, Merck and Co. provided bibliographic data on file for losartan.

STUDY SELECTION

Emphasis was placed on clinical and pharmacokinetic studies in humans. Controlled, double-blind studies were evaluated to assess the efficacy and adverse effect profile of losartan.

DATA SYNTHESIS

Losartan is a nonpeptide, competitive antagonist of the type I angiotensin II receptor. In comparative clinical trials, losartan appears to have antihypertensive efficacy similar to that of the angiotensin-converting enzyme (ACE) inhibitors. Losartan is well tolerated, with an adverse effect profile similar to that of placebo and a reduced incidence of cough versus that with ACE inhibitors. A combination product consisting of losartan 50 mg and hydrochlorothiazide 12.5 mg has also received approval for the treatment of hypertension. The combination product is not indicated for initial therapy, but is recommended for patients who do not respond adequately to losartan monotherapy. The angiotensin II receptor antagonists are also being investigated for beneficial effects in patients with ventricular hypertrophy, renal disease, and heart failure.

CONCLUSIONS

Losartan, the first angiotensin II receptor antagonist to receive approval for use in the US, appears to be an effective new antihypertensive agent with an adverse effect profile similar to that of placebo. Losartan may be an alternative for patients who cannot tolerate ACE inhibitors. However, the effect of losartan on mortality remains to be evaluated. The role of the angiotensin II receptor antagonists in areas such as ventricular hypertrophy, renal function, and heart failure has yet to be determined.

First dose hypotension with enalapril and prazosin in congestive heart failure

Since the introduction of angiotensin converting enzyme inhibitors into the adjunctive treatment of patients with congestive heart failure, cases of severe hypotension, especially on the first day of treatment, have occasionally been reported. To assess the safety of the angiotensin converting enzyme inhibitor enalapril a multicenter, open, randomized, prazosin-controlled trial was designed comparing the incidence and severity of symptomatic hypotension on the first day of treatment. Trial medication was 2.5 mg enalapril or 0.5 mg prazosin. Subjects were 1210 inpatients with New York Heart Association functional class (I)/II and III who were not adequately compensated with digitalis and/or diuretics. In the group receiving enalapril, 3 patients (0.5%) experienced severe hypotension on day 1 and 28 patients (4.7%) moderate hypotension. In those given prazosin, 15 patients (2.6%) experienced severe hypotension and 60 patients (10.3%) moderate hypotension. The difference is statistically significant (P less than or equal to 0.000012). All patients recovered. It was concluded that treatment of patients suffering from congestive heart failure New York Heart Association functional class (I)/II or III with enalapril is comparably well tolerated.

Intravenous enalaprilat therapy for hypertension

The angiotensin-converting enzyme inhibitor enalapril is available for intravenous administration in the form of enalaprilat. Intravenous enalaprilat is indicated for the management of hypertension when oral therapy is not feasible. However, there are no reports of intravenous enalaprilat therapy exceeding one week in duration. We report the case of a critically ill, 39-year-old woman who received intravenous enalaprilat for the management of hypertension for a period of 21 days. The patient's blood pressure and heart rate were controlled adequately on a regimen of enalaprilat 1.25 mg iv piggyback q6h without any apparent adverse effects.

Angiotensin converting enzyme inhibitors: comparative structure, pharmacokinetics, and pharmacodynamics

Angiotensin converting enzyme (ACE) inhibitors are a novel class of antihypertensive and anticongestive heart failure agents with wide patient and physician acceptability. By blocking the formation of angiotensin II in blood and tissue, all ACE inhibitors significantly lower systemic vascular resistance, lower blood pressure, and improve cardiac function, while maintaining or enhancing perfusion of vital organs: kidneys, brain, and heart. Captopril is the first oral ACE inhibitor with an active sulfhydryl group. Enalapril and lisinopril are potent nonsulfhydryl inhibitors of ACE characterized by weak chelating properties. The side effects of skin rashes, pruritus, taste abnormalities, oral ulcers, pemphigus, and blood dyscrasias have been considered to be strongly characteristic of penicillaminelike drugs, including the sulfhydryl ACE inhibitors. The class effects of cough, angio-edema, hyperkalemia, nonoliguric functional renal insufficiency, and hypotension can occur with equal frequency with all ACE inhibitors. It is unclear whether the many yet investigational ACE inhibitors would have distinct advantages over captopril, enalapril, lisinopril, and enalaprilat. This paper reviews the comparative structure and clinical pharmacology of the three commercially available but chemically different oral ACE inhibitors.

Angiotensin-converting enzyme inhibitors in heart failure

Recognition of the importance of the renin-angiotension-aldosterone system in heart failure, along with an appreciation of the hemodynamic benefits of vasodilator therapy has led to the widespread use of angiotensin-converting enzyme (ACE) inhibitors in the treatment of heart failure. The ACE inhibitors are the only class of vasodilator agents shown to have a significant protective effect against mortality in patients with heart failure.

Hemodynamic effects of lisinopril after long-term administration in congestive heart failure

To determine whether acute effects of the angiotensin converting enzyme inhibitor lisinopril are maintained during long-term therapy, 19 patients were studied using right-sided heart catheterization before an initial randomized dose of lisinopril and again after 12 weeks of maintenance lisinopril therapy. During initial evaluation, lisinopril produced significant decreases in mean systemic arterial pressure, pulmonary artery wedge pressure, systemic vascular resistance, mean pulmonary arterial pressure, mean right atrial pressure and pulmonary vascular resistance, and concomitant increases in cardiac index and stroke volume index. After 12 weeks of therapy with lisinopril, the dosage of which was titrated to produce optimal relief of symptoms of congestive heart failure (CHF), repeat hemodynamic studies revealed persistent significant reductions in baseline systemic arterial pressure, pulmonary artery wedge pressure, mean pulmonary arterial pressure and systemic vascular resistance. However, the increases in cardiac index and stroke volume index were not statistically significant. To determine if further acute hemodynamic changes occur during long-term therapy, the patients were readministered a dose of lisinopril. This caused further decreases in systemic arterial pressure, mean pulmonary arterial pressure, pulmonary artery wedge pressure, systemic vascular resistance and mean right atrial pressure, and an increase in cardiac index. Lisinopril did not change stroke work index at either initial or rechallenge study. This study indicates that in patients with CHF treated with lisinopril, acute hemodynamic effects persist after 12 weeks of therapy, and acute hemodynamic response continues to occur upon drug readministration.

Long-term effects of a once-a-day versus twice-a-day regimen of enalapril for congestive heart failure

Although an abundance of short-term clinical trials has evaluated the use of enalapril in congestive heart failure (CHF), there has been a paucity of data regarding the long-term effects of this angiotensin-converting enzyme inhibitor. Moreover, a question has arisen as to whether a once- or twice-daily dosing schedule is preferable. To address these issues, a multicenter trial was conducted with the objective of obtaining long-term (48 weeks) experience with enalapril in 142 patients with CHF. A subgroup of patients (n = 88) were randomized to receive enalapril in a dosing schedule of either 20 mg once daily or 10 mg twice daily. Of the overall group, 96 patients completed the 48 weeks of follow-up. Improvement in New York Heart Association functional class, exercise duration and left ventricular ejection fraction was observed. Improvement in clinical status was seen in 68% of all patients, whereas conditions in 5% worsened with enalapril therapy. The most frequent adverse experiences were dizziness and hypotension. There were no obvious differences between the effects of the once- and twice-daily dosing regimens, with doses of 20 mg/day and 2.5 to 15 mg/day being given to about 70 and 30% of patients, respectively. Enalapril appears to provide well-tolerated and effective long-term therapy for CHF.

Comparison of lisinopril versus placebo for congestive heart failure

A multicenter, randomized, double-blind assessment of 130 patients with congestive heart failure (New York Heart Association functional classes II to IV) was undertaken to assess the therapeutic efficacy of lisinopril, an angiotensin-converting enzyme inhibitor. All the subjects received concurrent therapy with digoxin and diuretics. Assessments performed periodically over 12 weeks revealed that the active treatment was associated with significant improvements in treadmill exercise time, cardiothoracic ratio, ejection fraction, functional status and clinical signs and symptoms of heart failure. Lisinopril exhibited a mild first-dose effect on blood pressure that was not significantly different from that observed with placebo. The incidence of adverse experiences was not markedly different in the 2 study groups, with only mild hypotension and dizziness occurring more frequently in association with the active medication.

Acute hemodynamic and hormonal effects of ramipril in chronic congestive heart failure and comparison with captopril

Acute hemodynamic and hormonal responses to ramipril in comparison with captopril were studied in 10 patients with moderate to severe congestive heart failure in an open, randomized study. Both drugs were given to 5 patients each in 2 increasing doses on 2 successive days. After 5 mg of ramipril angiotensin converting enzyme (ACE) activity was significantly decreased during 24 hours with a maximum decrease 4 hours after administration. Mean arterial blood pressure decreased from 84 +/- 5 to 62 +/- 5 mm Hg at 4 hours and 71 +/- 4 mm Hg at 12 hours, respectively, after this dose. Capillary wedge pressure decreased from 19 +/- 1 mm Hg to 13 +/- 1 mm Hg at 4 hours with a maximum increase in cardiac output from 3.8 +/- 0.3 liters/min to 4.4 +/- 0.3 liters/min at 2 hours. No significant cardiac effects were present 8 hours after administration. After 10 mg of ramipril, cardiac and hormonal effects showed a quicker onset of action and longer duration compared with the 5 mg dose. Mean arterial pressure decreased to 61 +/- 6 mm Hg. Similar effects were seen after captopril, but with a significantly shorter duration. Mean arterial pressure decreased from 82 +/- 4 mm Hg to 64 +/- 5 mm Hg after 12.5 mg and to 58 +/- 6 mm Hg after 25 mg of captopril. In patients with congestive heart failure ramipril has the hemodynamic profile of a long-acting and potent ACE inhibitor. Significant cardiac effects are present during 4 to 8 hours and ACE activity is still significantly inhibited 24 hours after a single dose of ramipril.(ABSTRACT TRUNCATED AT 250 WORDS)