The use of esmolol, nicardipine, or their combination to blunt hemodynamic changes after laryngoscopy and tracheal intubation

Laryngoscopy and tracheal intubation (LTI) often provoke an undesirable increase in blood pressure (BP) and/or heart rate (HR). We tested the premise that nicardipine (NIC) and esmolol (ESM) in combination (COMB) would oppose both. Adult surgical patients received pretreatment (randomized) with IV bolus NIC 30 microg/kg (n = 31), ESM 1.0 mg/kg (n = 34), or COMB (one-half dose each, n = 32). Peak BP and HR after LTI were compared with controls (CONT; n = 35) with no pretreatment. Anesthetic induction was standardized: IV thiopental (5-7 mg/kg), fentanyl (1-2 microg/kg), and succinylcholine (1.5 mg/kg). Systolic (S), diastolic (D), and mean (M) BP and HR awake before pretreatment (baseline) were similar in all test groups. No patient was treated for hypotension, bradycardia, or tachycardia after pretreatment or anesthetic induction. Peak HR after LTI was increased versus baseline in CONT and all test groups, but did not differ from CONT among the test groups. Peak SBP and DBP increased versus baseline in CONT, and with ESM and NIC, but not COMB. Peak SBP, DBP, and MBP were increased with ESM versus COMB, and peak DBP with ESM versus NIC. Compared with no pretreatment before the IV induction of general anesthesia, the peak increase in BP after LTI is best blunted by the combination of nicardipine and ESM, compared with either drug alone. No single drug or combination in the doses tested opposed increased HR.

IMPLICATIONS

Compared with no pretreatment before the IV induction of general anesthesia, the peak increase in blood pressure after laryngoscopy and tracheal intubation is best blunted by the combination of nicardipine and esmolol, compared with either drug alone. No single drug or combination in the doses tested opposed increased heart rate.

Predictors of improvement in left ventricular ejection fraction with carvedilol for congestive heart failure

BACKGROUND

Beta-blocker therapy has been reported to improve survival and left ventricular ejection fraction (LVEF) in the setting of congestive heart failure (CHF). The magnitude and predictors of improved LVEF are unclear.

METHODS

A total of 295 patients were enrolled in the study. Inclusion criteria were LVEF <35% at baseline and symptomatic (New York Heart Association class II to IV) CHF despite treatment with at minimum an angiotensin-converting enzyme inhibitor. Carvedilol was initiated at 3.125 mg twice daily and titrated to a target dose of 25 or 50 mg twice daily, depending on the patient's weight. Paired pretreatment baseline and 9 months with treatment follow-up quantitative LVEFs (assessed by resting radionuclide ventriculograms) were obtained in 161 (55 %) of the patients.

RESULTS

LVEF improved from 25% +/- 6% at baseline to 36%+/-12% at follow-up (P<.001). Mean change in LVEF (deltaLVEF) was greater for nonischemic cardiomyopathy (NICM) (+14.5+/-2 LVEF points) than ischemic cardiomyopathy (deltaLVEF +/- 7.6+/-10 EF points, P = .001). The deltaLVEF was > or =21 LVEF points in 30% of the NICM group versus 10% of the ischemic cardiomyopathy group. Conversely, the deltaLVEF was unchanged to minimally improved (< or =5 LVEF points) in 21% of the NICM group versus 52% of the ischemic cardiomyopathy group. Multivariable analysis identified NICM and recent onset of congestive heart failure as correlates of improved LVEF.

CONCLUSIONS

Carvedilol significantly improved LVEF, especially in patients with NICM and those with recent onset of CHF.

Hypotension with dobutamine: beta-adrenergic antagonist selectivity at low doses of carvedilol

OBJECTIVE

To report a case of marked hypotension resulting from the concomitant use of low-dose carvedilol and intravenous dobutamine.

CASE SUMMARY

A 54-year-old white man with severe heart failure was placed on carvedilol 3.125 mg orally twice a day; three days later the dosage was increased to 6.25 mg orally twice a day. His symptoms of heart failure worsened with increasing fluid retention, orthopnea, paroxysmal nocturnal dyspnea, and elevated blood urea nitrogen and creatinine. He was admitted for treatment of decompensated heart failure with intravenous dobutamine. With each increase in intravenous dobutamine, systolic blood pressure fell. Dobutamine was discontinued when systolic blood pressure reached 56 mm Hg. In a subsequent admission for decompensated heart failure, when the patient was not taking carvedilol, he was treated with intravenous dobutamine and systolic blood pressure increased.

DISCUSSION

Although carvedilol is a nonselective beta-adrenergic antagonist, at low doses it is a selective beta1-adrenergic antagonist. Dobutamine is a beta1-, beta2-, and alpha1-adrenergic agonist. Typically, patients with heart failure treated with intravenous dobutamine have a small increase in systolic blood pressure. We propose that the drop in blood pressure with dobutamine in this patient was caused by a fall in systemic vascular resistance due to vascular beta2-adrenergic receptor activation. The normal increase in cardiac output was partially blocked by selective beta1-adrenergic blockade at low doses of carvedilol.

CONCLUSIONS

Beta-adrenergic blockade with carvedilol is now common therapy for patients with congestive heart failure. Intravenous dobutamine is often used when these patients have worsening heart failure. Recognition that treatment with dobutamine in patients taking low doses of carvedilol may result in hypotension is important for appropriate monitoring and therapy.

Impact of concurrent amiodarone treatment on the tolerability and efficacy of carvedilol in patients with chronic heart failure

OBJECTIVE

To assess the safety and efficacy of carvedilol when administered to heart failure patients already receiving amiodarone.

DESIGN

Retrospective analysis of the clinical outcome of 230 patients treated with carvedilol for chronic heart failure, stratified according to whether they were already receiving amiodarone (amiodarone group, 80 patients) or not (non-amiodarone group, 130 patients) at baseline.

SETTING

Heart failure clinic at a university affiliated public teaching hospital.

MAIN OUTCOME MEASURES

Incidence of adverse events; changes in functional status and echocardiographic dimensions at three months.

RESULTS

Adverse reactions to carvedilol occurred in 33 (41%) of the amiodarone group and 43 (29%) of the non-amiodarone group (p = 0.049). Carvedilol was discontinued in 21 (26%) of the amiodarone group and 37 (25%) of the non-amiodarone group (NS). The clinical outcome at three months did not differ significantly between the two groups; 31 (39%) of the amiodarone group improved their New York Heart Association status, 28 (35%) were unchanged, and 21 (26%) deteriorated compared with 67 (45%), 51 (34%), and 32 (21%), respectively, for the non-amiodarone group (NS). Both groups had highly significant decreases in heart rate and left ventricular end systolic dimension, and a significant increase in left ventricular ejection fraction after three months of carvedilol treatment, with no significant differences between the groups.

CONCLUSIONS

The beneficial effects of carvedilol on left ventricular remodelling, systolic function, and symptomatic status are not affected by concurrent treatment with amiodarone. Adverse reactions necessitating cessation of carvedilol are no more frequent in patients receiving amiodarone.

The safety and effectiveness of esmolol in the perioperative period in patients undergoing abdominal aortic surgery

OBJECTIVES

To determine (1) if perioperative use of esmolol in major vascular surgery patients provides strict heart rate (HR) control, (2) what doses of esmolol are required to do this, and (3) does this control influence myocardial ischemia or result in adverse consequences.

DESIGN

Prospective study of 40 patients randomized to two groups: The HR was controlled to either less than 80 beats/min (group 80) or less than 110 beats/min (group 110) using esmolol. Patients were monitored continuously for electrocardiographic changes perioperatively. HR control began after induction of anesthesia and continued for 48 hours thereafter.

SETTING

Operating room and intensive care unit.

PATIENTS

Patients undergoing abdominal vascular surgery involving aortic cross-clamping.

INTERVENTIONS

Esmolol was titrated until the target HR was met.

MEASUREMENTS AND RESULTS

Only one patient demonstrated an adverse effect. The median infusion rates were 100 and 12.5 microg/kg/min for groups 80 and 110. Target HR was met less in group 80 than in group 110, primarily in the postoperative period. Ischemia patterns were not significantly different between groups.

CONCLUSION

Using esmolol for HR control in the intraoperative period for abdominal vascular surgery patients is effective and safe. HR control was much less effective in the postoperative period, but esmolol is safe when used at recommended doses. Further study with a larger number of patients is necessary to determine whether strict HR control with esmolol affects the incidence of myocardial ischemia or infarction in this patient population.

Comparison of efficacy of intravenous diltiazem and esmolol in terminating supraventricular tachycardia

OBJECTIVE

Paroxysmal supraventricular tachycardia (PSVT) can be effectively terminated by the intravenous administration of adenosine or verapamil. However adenosine is expensive and injectable verapamil currently is scarcely available. While intravenous diltiazem has been shown to be useful for terminating PSVT, the efficacy of esmolol in this regard has not been evaluated previously. Hence these latter two drugs were studied for their efficacy in terminating PSVT.

METHODS

A prospective, randomised, crossover study was undertaken in patients presenting with hemodynamically tolerated PSVT to the ICCU. While 50 patients had been planned for the trial, the study had to be prematurely terminated after 32 patients had been enrolled due to the marked superiority of diltiazem. Two sequential doses with a 5 minute interval of either drug were administered before crossover. Diltiazem was given in a dose of 0.25 mg/kg while the esmolol dose was 0.5 mg/kg.

RESULTS

Diltiazem terminated PSVT in all the 16 patients in whom it was given as the first drug. The 12 patients who did not respond to esmolol were also effectively treated with diltiazem. Thus totally 28/28 patients responded to diltiazem while only 4/16 patients responded to esmolol (p < 0.001). Of the 28 patients who responded to diltiazem, in 13 patients the second bolus of diltiazem worked after the first one had failed. No significant adverse effects were seen.

CONCLUSION

Intravenous diltiazem is highly effective and safe for terminating PSVT. When the first bolus is ineffective, the second bolus given after 5 minutes usually succeeds. Esmolol in the dose of 0.5 mg/kg has poor efficacy for terminating PSVT, even when 2 boluses are administered.

[Prospective evaluation of effect of carvedilol therapy on heart rate variability in patients with dilated cardiomyopathy]

The aim of the present study was to assess the effects of carvedilol therapy in addition to conventional heart failure therapy on heart rate variability (HRV) and on left ventricular function in 14 patients with mild to moderate heart failure due to idiopathic dilated cardiomyopathy (IDC). After a 3- to 4-week titration period, carvedilol was titrated up to 50mg daily, or the highest dose tolerated (at least 25mg daily). Maintenance treatment was then continued for 8 weeks. Digital 24-hour Holter recordings were obtained at baseline and after 8 weeks of carvedilol therapy. HRV for the entire 24-hour period was computed in the time domain using the Oxford Medilog Excel 2 analysis system. Measures of HRV included the mean of all coupling intervals between normal beats (RRm), the standard deviation of all normal RR intervals (SDNN), the square root of the mean of the squared differences between adjacent normal RR intervals (rMSSD), and the proportion of adjacent normal RR intervals differing >50 ms (pNN50). Additional treatment with carvedilol induced a significant increase in HRV: SDNN increased from 77+/-21 ms to 110+/-22 ms (p=0.001), rMSSD from 19+/-7 ms to 26+/-7 ms (p=0.02), and mean pNN50-value increased from 1.7+/-1.3% to 5.5+/-4.5% (p<0.01) under therapy with carvedilol. Mean heart rate on carvedilol calculated over 24 hours was 13 beats less than at baseline (75 bpm versus 88 bpm, p<0.01). After 2 months of additional treatment with carvedilol, both hemodynamic and clinical parameters improved: left ventricular ejection fraction increased from 24+/-7% to 30+/-10% (p<0.05), and New York Heart Association class decreased from 2.5+/-0.8 to 1.8+/-0.7 (p<0.05). In summary, eight weeks of additional carvedilol therapy induced a significant increase in HRV parameters related to parasympathetic activity in patients with IDC. Whether increased vagal tone may contribute to the protective effect of carvedilol has to be evaluated by further studies.

[Clinical effect of arotinolol hydrochloride and its influence on renal function in elderly patients with essential hypertension]

Arotinolol hydrochloride with alpha-and beta-receptor blocking action, developed in Japan, is mainly used for the treatment of hypertension. The study population consisted of 42 outpatients with essential hypertension with a blood pressure greater or equal to 160/96 mmHg. 10 men and 32 women, with a mean age of 77.5 year. The patients received 10 mg arotinolol hydrochloride daily for 24 weeks which was taken orally twice a day. We evaluated the changes of blood pressure, heart rate and chief complaints of patients before and every 4 weeks during treatment and the renal function before, 12 weeks after and 24 weeks after, the administration of arotinolol hydrochloride. Blood pressure and heart rate decreased significantly after 4 weeks of treatment with arotinolol hydrochloride (p < 0.05). However, no significant changes were found in blood urea nitrogen, serum creatinine, serum albumin, beta2-microglobuline, NAG or creatinine clearance during the 24 weeks of treatment. These results indicate that arotinolol hydrochloride has antihypertensive effects without renal dysfunction in elderly patients with essential hypertension.

Nifedipine and arotinolol in combination for accelerated-malignant hypertension: results of one year follow-up

The effects of a combined therapy with a calcium channel antagonist and alphabeta-blocker in patients with accelerated-malignant hypertension on blood pressure and renal function were examined. Thirteen patients presented with the clinical features of malignant hypertension (diastolic blood pressure >130 mmHg, retinal damage and progressive renal failure) at our hospital, over the 3 yr period from 1995 to 1997. These patients were treated with both a calcium antagonist, 60-80 mg/d dose of long acting nifedipine, and an alphabeta-blocker, 20 mg/d dose of arotinolol, for over 12 mo. At admission, the average blood pressure of the patients was 233+/-8/144+/-3 mmHg. The level of serum creatinine in these patients was 6.2+/-1.0 mg/dl. Intermittent hemodialysis therapy was introduced in 7 patients. Three days after treatment, blood pressure decreased to 162+/-4/102+/-4 mmHg. A month later, blood pressure decreased to 148+/-3/89+/-2 mmHg and serum creatinine levels were 3.6+/-0.4 mg/dl. Renal function in these patients improved, and they completely recovered from renal dysfunction, allowing withdrawal of haemodialysis therapy. One year later, the blood pressure in all of these patients was well controlled and no further renal deterioration was observed, except in one patient. Despite the reduction in blood pressure, one patient was on hemodialysis three times a week after 8 mo of treatment. From these finding, it is concluded that combination therapy with a calcium antagonist and alphabeta-blocker is effective in both the reduction of highly elevated blood pressure and protection of the kidneys, resulting in amelioration of accelerated-malignant hypertension.

Tolerability and efficacy of carvedilol in patients with New York Heart Association class IV heart failure

OBJECTIVES

The purpose of this study was to assess the tolerability and efficacy of carvedilol in patients with New York Heart Association (NYHA) functional class IV symptoms.

BACKGROUND

Carvedilol, a nonselective beta-adrenergic blocking drug with alpha-adrenergic blocking and antioxidant properties, has been shown to improve left ventricular function and clinical outcome in patients with mild to moderate chronic heart failure.

METHODS

We retrospectively analyzed the outcomes of 230 patients with heart failure treated with carvedilol who were stratified according to baseline functional class: 63 patients were NYHA class IV and 167 were NYHA class I, II or III. Carvedilol was commenced at 3.125 mg b.i.d. and titrated to 25 mg b.i.d. as tolerated. Patients with class IV symptoms were older (p = 0.03), had lower left ventricular fractional shortening (p < 0.001), had lower six-min walk distance (p < 0.001) and were receiving more heart failure medications at baseline compared with less symptomatic patients.

RESULTS

Nonfatal adverse events while taking carvedilol occurred more frequently in class IV patients (43% vs. 24%, p < 0.0001), and more often resulted in permanent withdrawal of the drug (25% vs. 13%, p < 0.01). Thirty-seven (59%) patients who were NYHA class IV at baseline had improved by one or more functional class at 3 months, 8 (13%) were unchanged and 18 (29%) had deteriorated or died. Among the less symptomatic group, 62 (37%) patients had improved their NYHA status at 3 months, 73 (44%) were unchanged and 32 (19%) had deteriorated or died. The differences in symptomatic outcome at three months between the two groups were statistically significant (p = 0.001, chi-square analysis). Both groups demonstrated similar significant improvements in left ventricular dimensions and systolic function.

CONCLUSIONS

Patients with chronic NYHA class IV heart failure are more likely to develop adverse events during initiation and dose titration when compared with less symptomatic patients but are more likely to show symptomatic improvement in the long term. We conclude that carvedilol is a useful adjunctive therapy for patients with NYHA class IV heart failure; however, they require close observation during initiation and titration of the drug.

Comparison of safety and efficacy of carvedilol and metoprolol in stable angina pectoris

In a double-blind, randomized, 3-month multicenter study, the safety and tolerability and the antianginal and anti-ischemic efficacy of carvedilol 25 to 50 mg twice daily were assessed in comparison with metoprolol 50 to 100 mg twice daily in younger and elderly patients with stable angina. After a 7-day placebo run-in at the end of which a symptom-limited bicycle ergometric exercise was performed, 368 patients were randomly allocated to the parallel treatment groups. After 4 weeks of therapy with a low dose, a further exercise test was performed and patients were titrated in single-blind fashion to the higher dose if the increase in total exercise time was < 1 minute, and there was no safety concern. After a further 8 weeks of treatment a third exercise test was performed. Carvedilol low dose/high dose was shown to be at least as safe and well tolerated as metoprolol low dose/high dose both in younger and elderly patients. There were no hitherto unknown adverse events and no marked change in the types of events after increase of the doses. Early adverse events after treatment initiation or uptitration were equal with both medications, indicating no particular risk associated with carvedilol's vasodilatory action. No rebound phenomena were observed. Both drugs showed good antianginal and anti-ischemic efficacy, with marked increases on uptitration including patients > or = 65 years of age. However, in the doses selected, which appeared equipotent with respect to beta blockade, carvedilol's improvement of time to 1-mm ST-segment depression was statistically significantly greater than that of metoprolol. This could be due to its additional vasodilatory or antioxidative actions. Based on the safety and efficacy data of the present study, use of the higher of the 2 recommended doses of carvedilol and metoprolol appears justified in younger and elderly patients without adequate therapeutic control at lower doses.

Effect of oxytocin receptor and beta2-adrenoceptor blockade on myometrial oxytocin receptors in parturient rats

It has been proposed that the rise in myometrial oxytocin receptor (OTR) concentrations at term triggers parturition. In the present study, we have shown that in vivo infusion of the beta2-adrenoceptor (beta2AR) antagonist ICI-118.551 in late pregnant rats prevents the rise in myometrial OTR binding normally seen during delivery. A reduced contractile responsiveness of uterine strips isolated from rats in labor when challenged with oxytocin (OT) and a slight shortening of gestation accompanied this effect. OTR mRNA levels were, however, unaltered after the treatment, suggesting that the effect of beta2AR blockade on myometrial OTR was posttranscriptional or due to influences on extra-myometrial tissue. Infusion of the OTR antagonist atosiban down-regulated OTR binding sites in the parturient myometrium and resulted in an impaired contractile response to OT without affecting gestational length. OTR gene expression did not change, as seen from unchanged OTR mRNA values. Neither atosiban nor ICI-118.551 infusions alone changed fetal mortality. A significant increase in the incidence of fetal deaths was found, however, when rats were treated with a combination of atosiban and ICI-118.551. This treatment also down-regulated myometrial OTR and weakened the contractile response to OT, but it did not change gestational length. We conclude that the timing and onset of a normal parturition as well as a favorable outcome seem to be independent of a rise in OTR. This fact cannot exclude the possibility that an increase in OTR is of importance in the genesis of preterm labor. We suggest that beta2 stimulation up-regulates OTR during delivery. This effect may partly be responsible for the tachyphylaxis seen after the use of beta2 agonists to control preterm labor. We further suggest that OTR stimulation up-regulates OTR during labor. The OTR down-regulation seen after atosiban treatment adds to the direct relaxing effect of atosiban on the myometrium. In view of this, atosiban may prove to be a more useful tocolytic than the traditionally used beta2 agonists.

Effectiveness of three different doses of carvedilol for exertional angina. Carvedilol-Angina Study Group

Carvedilol is a nonselective beta-receptor antagonist with vasodilating properties primarily due to selective alpha-1 antagonism. This 4-treatment, 5-period, double-blind, crossover study evaluated the efficacy and safety of 3 doses of carvedilol (12.5, 25, and 50 mg given twice daily) versus placebo in 122 patients with chronic stable angina. Carvedilol in doses of 25 mg twice daily and 50 mg twice daily was statistically superior to placebo with respect to time to angina (placebo: 316 seconds; 25 mg carvedilol: 337 seconds, p = 0.0039; 50 mg: 345 seconds, p <0.0001) and time to 1-mm ST-segment depression (placebo: 301 seconds; 25 mg: 313 seconds; 50 mg: 323 seconds; p <0.0001). The percentage of patients reporting any adverse experience was slightly less in those receiving placebo (placebo: 28.4%; 12.5 mg: 33.1%; 25 mg: 34.5%; 50 mg: 31.9%). Carvedilol is effective and safe in treating patients with chronic stable angina.

Possible adverse skin reaction to carvedilol

As experience with beta-blocker use in patients with congestive heart failure is increasing, enthusiasm for carvedilol use in these patients is also increasing. Dermatological reactions to carvedilol are rare and have not been well described in the literature. A patient who developed an acute dermatological reaction after one dose of 3.125 mg carvedilol is presented. Given the rapid onset of symptoms experienced by the patient after a single, small dose of carvedilol, clinicians should be aware of the potential adverse effects of the drug.

Porcine hepatic response to sepsis and its amplification by an adrenergic receptor alpha1 agonist and a beta2 antagonist

1. We investigated the effect of adrenergic receptor stimulation or inhibition on the hepatic ultrastructural changes in a porcine faecal peritonitis model of multi-organ failure. We infused either the alpha1 adrenergic receptor agonist methoxamine or the beta2 adrenergic receptor antagonist ICI 118551 during 8 h of the study.2. Anaesthetized pigs (25-30 kg) were divided into four non-septic groups (control, non-septic, non-septic methoxamine and non-septic ICI 118551) and three septic groups (septic, septic methoxamine and septic ICI 118551).3. Changes in hepatic ultrastructure were measured by morphometric analysis. The septic group was significantly worse than all the non-septic groups. Septic methoxamine and septic ICI 118551 were significantly worse than the septic group.4. Septic methoxamine and septic ICI 118551 had a significantly increased perisinusoidal space; septic methoxamine had significant hepatocyte vacuolation.5. Hepatic ultrastructural changes were independent of hepatic blood flow.6. Septic methoxamine had significant myocardial depression.7. The alpha1 adrenergic receptor agonist methoxamine or the beta2 antagonist ICI 118551 both amplified the hepatic injury normally found during sepsis in our porcine model.8. These findings suggest that during sepsis a protective endogenous beta2 adrenergic receptor-mediated anti-inflammatory response is activated via cell membrane transduction to stimulate the trimeric G-protein complex Gs and activate the second cell messenger cAMP.9. In addition, it is likely that alpha1 adrenergic receptor agonists amplify the inflammatory response by stimulating the cell-surface receptor-linked trimeric G-protein complex to activate Gq and the second cell messenger phospholipase C.

[Contact allergy to beta blockaders in eye drops: cross allergy?]

INTRODUCTION

Beta-blockers in eye-drops are widely used for the treatment of glaucoma. The potential allergic effect was only recently recognized.

CASE REPORT

A 65-year-old man had been treated with eye-drops containing beta-blockers for bilateral chronic glaucoma for 14 years. During the last two years, he developed eczema localized on the upper and lower eyelids. Allergy screening confirmed the implication of timolol and befunolol which had been used successively. Later prescription of eye-drops containing carteolol led to recurrence of the eczema.

DISCUSSION

This case of contact allergy with three different beta-blockers in the same patient is similar to others reported in the literature. All beta-blockers have a similar chemical structure, but it cannot act as a haptene. The proposed hypothesis is a cross-sensitivity which develops after primary metabolism to a common aldehyde. The risk of recurrence is high if another beta-blocker eye-drop compound is prescribed in a sensitized patient. The risk of side effects in such sensitized patients when taking oral beta-blockers is unknown.

Treatment of chronic stable angina with carvedilol: a multiple-action neurohormonal antagonist. A review of controlled clinical trials

Beta-blockers and vasodilators, such as nitrates and calcium channel blockers, are all established antianginal therapies. These therapies have different antianginal mechanisms that dictate both their mode of action and their side-effect profile. An agent with both cardiac beta- and vascular alpha-receptor activity offers advantages over these conventional drugs. Carvedilol, a multiple-action neurohormonal antagonist, has potent antihypertensive and antianginal activity. Through its combination of pharmacological mechanisms, it reduces myocardial oxygen demand, increases myocardial blood supply and scavenges oxygen free radicals, which are capable of ischaemic damage. Studies have shown that carvedilol is at least as effective as other antianginal therapies in the management of chronic stable angina. Carvedilol is well tolerated--in several cases, the overall incidence of adverse events being lower than with other antianginal agents. These properties, combined with the documented antianginal effects, suggest that carvedilol may prove useful for the treatment of patients with chronic stable angina.

Electrocardiographic and clinical predictors of torsades de pointes induced by almokalant infusion in patients with chronic atrial fibrillation or flutter: a prospective study

The aim of this study was to identify predictors of torsades de pointes (TdP) in patients with atrial fibrillation (AF) or flutter exposed to the Class III antiarrhythmic drug almokalant. TdP can be caused by drugs that prolong myocardial repolarization. One hundred patients received almokalant infusion during AF (infusion 1) and 62 of the patients during sinus rhythm (SR) on the following day (infusion 2). Thirty-two patients converted to SR. Six patients developed TdP. During AF, T wave alternans was more common prior to infusion (baseline) in patients developing TdP (50% vs 4%, P < 0.01). After 30 minutes of infusion 1, the TdP patients exhibited a longer QT interval (493 +/- 114 vs 443 +/- 54 ms [mean +/- SD], P < 0.01), a larger precordial QT dispersion (50 +/- 74 vs 27 +/- 26 ms, P < 0.05), and a lower T wave amplitude (0.12 +/- 0.21 vs 0.24 +/- 0.16 mV, P < 0.01). After 30 minutes of infusion 2, they exhibited a longer QT interval (672 +/- 26 vs 489 +/- 74 ms, P < 0.001), a larger QT dispersion in precordial (82 +/- 7 vs 54 +/- 52 ms, P < 0.01) and extremity leads (163 +/- 0 vs 40 +/- 34 ms, P < 0.001), and T wave alternans was more common (100% vs 0%, P < 0.001). Risk factors for development of TdP were at baseline: female gender, ventricular extrasystoles, and treatment with diuretics; and, after 30 minutes of infusion: sequential bilateral bundle branch block, ventricular extrasystoles in bigeminy, and a biphasic T wave. Patients developing TdP exhibited early during almokalant infusion a pronounced QT prolongation, increased QT dispersion, and marked morphological T wave changes.

Effects of epanolol, a selective beta1-blocker with intrinsic sympathomimetic activity, in patients with ischemic left ventricular dysfunction

Recently, different beta-blockers have been shown to be effective in the treatment of chronic heart failure (CHF), but the importance of their ancillary properties is not clear. Epanolol is a selective beta1-blocker with intrinsic sympathomimetic activity, which has been shown useful in angina pectoris, but its value in patients with left ventricular (LV) dysfunction and CHF is unknown. We examined the effects of epanolol in patients with LV dysfunction (n = 8; mean LV ejection fraction, 0.33 +/- 0.08) and compared them with patients with normal LV function (n = 8; mean LV ejection fraction, 0.52 +/- 0.04). Measurement of invasive hemodynamics and neurohormones was performed at rest and during myocardial ischemia, which was induced by atrial pacing. All measurements were performed before and after epanolol. Before epanolol, pacing-induced ischemia led to a similar increase in norepinephrine and coronary sinus blood flow in both groups. After epanolol, the increase in neurohormones was more pronounced in the group with LV dysfunction (norepinephrine, 1,130 +/- 164 pg/ml for patients with LV dysfunction vs. 637 +/- 41 pg/ml for normal subjects; p < 0.05). A similar effect was observed for angiotensin II. Further, in the LV-dysfunction group, coronary sinus blood flow increased less, and coronary vascular resistance decreased less (both values, p < 0.05). Despite the fact that the increase in double product was decreased to a similar extent in both groups, ischemia was reduced only in normal LV function (p < 0.05). In ischemic LV dysfunction, neurohumoral activation after epanolol may impair adequate coronary flow response, and this may limit its antiischemic properties. Because of the small size of the study, no definitive inference on the clinical benefit of epanolol in patients with ischemic LV function can be made from this study.

Evaluation of intrinsic sympathomimetic activity of bucindolol and carvedilol in rat heart

Many beta-adrenoceptor antagonists are weak partial agonists, possessing significant intrinsic sympathomimetic activity (ISA). Under certain conditions, ISA may be deleterious through stimulation of beta 1- and/or beta 2-adrenoceptors in the heart. Drugs with ISA are particularly problematic in the treatment of congestive heart failure since agents that activate cardiac beta-adrenoceptors, such as xamoterol, have been associated with increases in the incidence of arrhythmia and mortality. Carvedilol was recently approved for the treatment of congestive heart failure, and bucindolol is currently in large clinical trials for this indication. In the present study, the ISA of bucindolol and carvedilol was evaluated in a standard model used to investigate ISA, the pithed rat. Both compounds produced dose-dependent inhibition of the positive-chronotropic effects of the non-selective beta-adrenoceptor agonist, isoproterenol, confirming that these drugs are beta-adrenoceptor antagonists. However, cumulative administration of bucindolol (10-1,000 micrograms/kg i.v.) in the pithed rat produced a significant dose-related increase in heart rate. The maximal increase in heart rate produced by bucindolol was 44% of that obtained with isoproterenol (90 +/- 6vs. 205 +/- 11 bpm, respectively). In marked contrast, cumulative administration of carvedilol (10-1,000 micrograms/kg i.v.) had no significant effect on resting heart rate in the pithed rat. The maximal increase in heart rate elicited by bucindolol (1,000 micrograms/kg i.v.) was inhibited by treatment with the competitive beta-adrenoceptor antagonist, propranolol (99 +/- 8.7 vs. 26 +/- 2.6 bpm), confirming that the ISA observed with bucindolol was mediated through stimulation of myocardial beta-adrenoceptors. Carvedilol, which had no ISA, antagonized the ISA of bucindolol, and was as effective as propranolol in blocking the ISA of bucindolol (99 +/- 8.7 vs. 27 +/- 2.3 bpm). In summary, bucindolol and carvedilol are both potent beta-adrenoceptor antagonists in the pithed rat: however, only bucindolol possesses beta-adrenoceptor-mediated ISA.

Effects of a hydroxylated metabolite of the beta-andrenoreceptor antagonist, carvedilol, on post-ischaemic splachnic tissue injury

1 Reactive oxygen species have been demonstrated to play a critical role in post-ischaemic tissue injury. The present experiment was designed to evaluate the effects of SB 211475, a hydroxylated metabolite of the new beta-adrenoceptor antagonist, carvedilol, on rat splanchnic ischaemia (SI, 60 min) and reperfusion(R)-induced shock and tissue injury. 2 Administration of SB 211475 two min before R attenuated SI/R injury in a dose-dependent manner. At doses of 0.5 mg kg(-1) and 1.0 mg kg(-1), SB 211475 exerted significant anti-shock and endothelial protective effects, characterized by prolonged survival times, increased survival rates, attenuated increases in tissue myeloperoxidase activity and haematocrits, and preserved endothelium-dependent vasorelaxation. 3 Administration of 1 mg kg(-1) carvedilol attenuated shock-induced tissue injury and endothelial dysfunction. However, administration of 0.5 mg kg(-1) carvedilol had no protective effects on post-ischaemic tissue injury. 4 Previous studies have shown that SB 211475 has virtually no beta-blocking activity but possesses more potent antioxidant activity than carvedilol. In the present study, SB 211475 exerted more potent protective effects than the parent compound, suggesting that this metabolite of carvedilol is superior to carvedilol with regard to its protection against post-ischaemia tissue injury.

Results of therapy with carvedilol, a beta-blocker vasodilator with antioxidant properties, in hypertensive patients

Carvedilol is a new beta-blocker antihypertensive agent with vasodilating properties secondary to alpha 1-blocking activity. Peripheral vascular resistance is reduced and cardiac output and renal function are not altered with carvedilol. The antihypertensive effects of this agent are equivalent to those of other beta-blockers, calcium channel blockers, angiotensin converting enzyme inhibitors, and diuretics. Carvedilol has a neutral effect on lipids and glucose metabolism. The percentage of responders is increased when carvedilol is combined with a diuretic. This agent has several unique properties. In addition to its antihypertensive effects, carvedilol in vitro and in vivo has been shown to have antiproliferative effects on smooth muscle cells and to inhibit the action of oxygen-free radicals. The antioxidant properties of this compound are significantly greater than those of vitamin E. In animal models, carvedilol may slow the process of atherogenesis, reduce infarct size, and improve postinfarction survival to a greater degree than other beta-blockers. Recent studies have demonstrated that carvedilol reduces morbidity and mortality in patients with congestive heart failure who are already receiving angiotensin converting enzyme inhibitors, diuretics, and digitalis. The antioxidant and antiproliferative activities of carvedilol may present an advantage over other available antihypertensive medications.

[The use of Cordanum in combination with Corinfar-Retard for the treatment of ectopic arrhythmias in the sick sinus syndrome in patients with ischemic heart disease]

38 patients with ischemic heart disease (IHD) and sick sinus syndrome (SSS) received combined therapy with nifedipine (Corinfar-Retard) and talinolol (Cordanum). The former drug had a positive chronotropic effect on the heart, the latter's chronotropic effect was slightly negative. All the patients had sinus bradycardia and ectopic arrhythmia which needed therapeutic correction: supraventricular and ventricular extrasystoles, fibrillation paroxysms or/and atrial flutter, paroxysmal supraventricular tachycardia, ventricular tachycardia. Cordanum was given in a dose 50 mg twice a day, Corinfar-Retard 20 mg twice a day for 16 days. 30 patients responded to the treatment. In addition to good subjective response, episodes of extrasystoles, paroxysms, flutter and fibrillation occurred much less frequently. Side effects resulted in the treatment discontinuation in 3 patients.

Effect of esmolol pretreatment on EEG seizure morphology in RUL ECT

Intravenous beta-blockers are an effective means of controlling heart rate and blood pressure during electroconvulsive therapy (ECT), but have been shown to decrease seizure duration. While the importance of seizure duration to the antidepressant response of ECT grows less certain, there is growing evidence that seizure morphology predicts the antidepressant effect of ECT. This study examined the impact of esmolol pretreatment on seizure morphology. Eighteen depressed patients (6 men, 12 women; 69 +/- 12.8 years old) received ECT with and without esmolol pretreatment in a randomized, blinded crossover design. The seizures were blindly rated for duration of motor convulsion, duration of electroencephalogram (EEG) seizure, degree of seizure regularity, and degree of postictal EEG suppression. Esmolol shortened the duration of the motor convulsion and degraded the quality of the ictal regularity. Routine administration of intravenous esmolol before ECT may cause a decrease in ictal regularity. Careful consideration should be given to the potential benefits of esmolol versus the deleterious effect on the electrophysiologic process. Esmolol may still be indicated on a case-by-case basis for extreme tachycardia or hypertension associated with ECT, and presumably poses no problem for the therapeutic effect of ECT if given after the seizure is over.

Stevens-Johnson syndrome associated with carvedilol therapy

Stevens-Johnson syndrome, related to carvedilol use, has not been previously reported as a serious adverse experience requiring hospitalization. We report this reaction in a 71-year-old man with stable ischemic cardiomyopathy.

The effect of esmolol on ST-segment depression and arrhythmias after electroconvulsive therapy

Electroconvulsive therapy (ECT) induces sympathetically mediated hemodynamic alterations that can be associated with myocardial ischemia and arrhythmia generation. Esmolol, a short-acting beta-blocker, blunts the hypertension and tachycardia seen with ECT. The purpose of this study is to determine whether esmolol use during ECT reduces the incidence of myocardial ischemia or arrhythmias after ECT. In a randomized, double-blind, placebo-controlled protocol, with each patient acting as his/her own control, the effects of esmolol on the incidence of myocardial ischemia and arrhythmias were studied using two-lead Holter monitoring for at least 2 h post-ECT. Nineteen patients underwent 71 ECT treatments (34 placebo, 37 esmolol), recording 746 h of Holter data. The esmolol group had significantly reduced heart rate and mean arterial pressure immediately after ECT. There was no difference in the incidence of ECG defined ischemia post-ECT between groups, with 7 of 19 (36.8%) patients in the esmolol group showing ST-segment depression compared with 5 of 19 (26.3%) in the placebo group. There was no difference between groups in arrhythmia detection. This experiment demonstrates that (a) ECT is associated with a significant incidence of ST-segment depression, (b) esmolol blunts the sympathetic discharge during ECT, and (c) esmolol does not reduce the incidence of post-ECT ischemia or arrhythmia.

Effects of almokalant, a class III antiarrhythmic agent, on supraventricular, reentrant tachycardias. Almokalant Paroxysmal Supraventricular Tachycardia Study Group

The aim of the present study was to investigate the effects of almokalant on sustained reentrant supraventricular tachycardias. Reentrant tachycardias were induced, using transesophageal atrial stimulation, in 82 patients with atrioventricular reentrant tachycardia (n = 54) or AV nodal reentrant tachycardia (n = 28). After a baseline procedure during which the tachycardia was induced and overdrive terminated, the tachycardia was reinduced and studied during 12 minutes of infusion of either placebo or almokalant, aiming at plasma concentrations of 20, 50, 100, and 150 nmol/l. Each patient was studied at two dose levels during the same procedure. There was an increase in the RR interval during tachycardia of 6% at 100 nmol/l (p = 0.001 vs. baseline tachycardia). The QT interval during tachycardia increased by 5% (p = 0.001) at 50 nmol/l and by 10% (p = 0.001) at 100 nmol/l. Bundle branch block during tachycardia developed in 13% during almokalant infusion, aiming at 20 nmol/l, in 25% at 50 nmol/l, in 50% at 100 nmol/l, and in 33% at 150 nmol/l. Rapid baseline tachycardia, increasing almokalant dose, and an increasing number of induced tachycardias correlated with the appearance of bundle branch block. In six patients with AV nodal reentrant tachycardia, 2:1 AV block occurred, in all cases preceded by bundle branch block. The QT prolongation during sustained tachycardia was larger in patients who were noninducible at the same plasma concentration level than in the inducible patients. Almokalant caused bundle branch block and 2:1 AV block during sustained supraventricular tachycardia. These findings emphasize the importance of studying drug effects at rates in the range of clinical tachycardias that expose the conduction system to the limits of its refractoriness.

Carvedilol. A reappraisal of its pharmacological properties and therapeutic use in cardiovascular disorders

Carvedilol competitively blocks beta 1, beta 2 and alpha 1 receptors. The drug lacks sympathomimetic activity and has vasodilating properties that are exerted primarily through alpha 1-blockade. Animal models indicate that carvedilol confers protection against myocardial necrosis, arrhythmia and cell damage caused by oxidising free radicals, and the drug has no adverse effects on plasma lipid profiles. Recent data have confirmed the antihypertensive efficacy of carvedilol in patients with mild to moderate essential hypertension. Carvedilol has similar efficacy to other beta-blocking agents, calcium antagonists, ACE inhibitors and hydrochlorothiazide. Carvedilol also improves exercise tolerance and ischaemic symptoms in patients with stable angina pectoris. Significant reductions in serious cardiac events after acute myocardial infarction and in frequency and severity of ischaemic events in patients with unstable angina have also been demonstrated. Interest in the use of carvedilol in patients with congestive heart failure (CHF) has culminated in the publication of a cumulative analysis of data from 1094 patients with mild to severe CHF who participated in the US Carvedilol Heart Failure Study Program (4 trials). After a median follow-up of 6.5 months, a significant overall reduction in mortality relative to placebo (3.2 vs 7.8%) was revealed in patients who had received carvedilol 6.25 to 50 mg twice daily (plus diuretics and ACE inhibitors). All-cause mortality, risk of hospitalisation for cardiovascular reasons and hospitalisation costs were also reduced significantly (by 65, 28% and 62%, respectively) in these trials. In addition, the Australia and New Zealand Heart Failure Research Collaborative Group showed a 26% reduction in the combined risk of death or hospitalisation with carvedilol 12.5 to 50 mg/day relative to placebo after a mean 19-month follow-up period in 415 patients with CHF (relative risk 0.74). Adverse events with carvedilol appear to be less frequent than with other beta-blocking agents, are dosage-related and are usually seen early in therapy. Events most commonly reported are related to the vasodilating (postural hypotension, dizziness and headaches) and the beta-blocking (dyspnoea, bronchospasm, bradycardia, malaise and asthenia) properties of the drug. Carvedilol appears to date to have little effect on the incidence of worsening heart failure. Concomitant administration of carvedilol with some medications requires monitoring. Carvedilol is therefore likely to have a beneficial role in the management of controlled CHF, but further clinical studies are required to show the place of beta-adrenoceptor blocking therapy in general in this indication, and the position of carvedilol relative to other similar agents. Carvedilol is also confirmed as effective in the management of mild to moderate hypertension and ischaemic heart disease.

Beneficial effects of intravenous and oral carvedilol treatment in acute myocardial infarction. A placebo-controlled, randomized trial

BACKGROUND

Evidence of efficacy and safety of beta-blockers after thrombolysis for acute myocardial infarction (AMI) is equivocal. Newer beta-blockers such as carvedilol have not been tested in this setting.

METHODS AND RESULTS

This study investigated the effects of acute (intravenous) and long-term (6 months, oral) treatment with carvedilol versus placebo in 151 consecutive patients with AMI. Exercise ECG, ambulatory monitoring, and two-dimensional echocardiography were performed before hospital discharge and at 3 and 6 months. All patients were followed up and cardiovascular events recorded. The Cox proportional hazards model was used to compare time from randomization with the occurrence of a cardiovascular event, and Kaplan-Meier survival curves were calculated. Carvedilol was found to be safe, and it significantly reduced cardiac events compared with placebo (18 on carvedilol and 31 on placebo, P < .02). Fifty-four patients had heart failure at study entry; 34 received carvedilol. There were no adverse effects of carvedilol therapy and no excess events in this subgroup. Carvedilol produced significant reductions in heart rate (P < .0001), blood pressure (P < .005) at rest, and rate-pressure product at peak exercise (P < .003), but exercise capacity was unchanged. Left ventricular ejection fraction was not altered significantly by carvedilol, but stroke volume was higher at pre-hospital discharge examination (63 versus 53 mL; P < .01). Diastolic filling of the left ventricle (E/A ratio) was also improved (1.2 versus 0.9; P < .001). In a subgroup with left ventricular ejection fraction < 45% (n = 49 patients; 24 on carvedilol and 25 on placebo), carvedilol showed attenuation of remodeling.

CONCLUSIONS

Carvedilol was well tolerated and safe to use in patients immediately after AMI, including those with heart failure, and significantly improved outcome.

Cardiopulmonary compromise after use of topical and submucosal α-agonists: Possible added complication by the use of β-blocker therapy

We report the specifics of 12 cases of severe hypertension after the intraoperative use of topical phenylephrine, submucosal epinephrine, or both. Ten of these 12 patients also developed severe pulmonary edema. Seven of the twelve were treated with β blockers; 3 of whom suffered cardiac arrest. We propose a common mechanism: the vasoconstrictors caused systemic hypertension, increased left ventricular afterload, decreased left ventricular compliance, and decreased cardiac output. In those patients treated with β blockers, decreased contractility and inability to increase heart rate further compromised cardiopulmonary function. (Otolaryngol Head Neck Surg 1997;117:56–61.)

Airborne contact dermatitis from 2-amino-2-methyl-1-propanol in a cosmetic company

The authors described two cases of airborne contact dermatitis caused by 2-amino-2-methyl-1-propanol (AMP 100) in two subjects with periorbital erythema and itching skin. The AMP 100 has been used to replace ammonia as a hair dye component in the cosmetic industry with the purpose to eliminate its smell. Patch tests proved positive only to dilutions of 10% and 20% in the two described patients, as well as in other six asymptomatic subjects operating in the same working environment. The authors have diagnosed an irritative airborne contact dermatitis by AMP 100.

[The effects of mid- and long-term administration (3-4 years) of carvedilol in patients with idiopathic dilated cardiomyopathy]

Carvedilol has been shown to determine a significant improvement in left ventricular function, symptoms, clinical course and prognosis of patients with chronic heart failure. However, these results were obtained in medium-term studies of < 1 year duration. We report the results obtained with long-term (3-4 years) carvedilol administration to 40 patients with idiopathic dilated cardiomyopathy who were initially recruited in a 4-month double-blind placebo-controlled trial. In the initial 4-month double-blind trial, 20 patients were randomized to placebo and 20 to carvedilol treatment. All patients, except one who was not on ACE-inhibitors, were on digoxin, furosemide and ACE-inhibitors. Carvedilol or placebo doses were progressively titrated, at weekly intervals, up to the maximal doses of 25 mg bid. After the initial 4-month double-blind phase, all patients were followed long term. Mean follow-up duration was 52 +/- 12 months (range 48-61). Among the 20 patients initially randomized to carvedilol administration, 4 died (3 for cardiac and 1 for extracardiac causes) and 2 underwent heart transplant. Among the 20 patients initially randomized to placebo, 5 died for cardiac causes, 3 underwent heart transplant and 4 were started on carvedilol because of progressive heart failure during the initial 4 months of the study. The remaining 8 patients, who were kept on digoxin, furosemide and ACE-inhibitors, were used as control group. Each patient underwent an assessment of clinical conditions (NYHA functional classification and Minnesota Living with Heart Failure questionnaire), equilibrium radionuclide ventriculography, and maximal cardiopulmonary bicycle exercise testing. Exams were performed before treatment, after 4 and 12 months, and at the end of the follow-up period. No significant difference between the carvedilol and control group was present at baseline. Compared with baseline, patients in the control group presented a significant increase in left ventricular end-diastolic volume after long-term follow-up (from 126 +/- 62 to 138 +/- 43 and 158 +/- 52 ml/m2 after 12 and 48 months, respectively). No significant difference, compared to baseline values, was noted. Patients on carvedilol presented a persistent improvement in left ventricular function. This was shown by the progressive increment in left ventricular ejection fraction from 22 +/- 6 to 34 +/- 11, 37 +/- 11 and 37 +/- 13%, after 4, 12 and 48 months, respectively (p < 0.001) with a concomitant reduction in left ventricular end-diastolic volume from 147 +/- 54 to 101 +/- 44 ml/m2 at the end of the follow-up (p < 0.05). NYHA functional class remained significantly improved, in comparison with baseline (2.6 +/- 0.5 to 1.9 +/- 0.3, 1.9 +/- 0.8 and 2.0 +/- 1.0 after 4, 12 and 48 months, respectively; p < 0.01). Maximal functional capacity, assessed as peak VO2 was not significantly changed after 4 months (from 15.2 +/- 3.6 to 16.4 +/- 4.0 ml/kg/min) and showed a tendency towards a further improvement after 12 months and at the end of the follow-up (17.3 +/- 5.6 and 17.2 +/- 5.3 ml/kg/min, respectively). These results show that the favorable effects of carvedilol administration on left ventricular function and clinical symptoms are maintained also after long-term treatment.

The use of esmolol in whole-body hyperthermia: cardiovascular effects

Whole-body hyperthermia (WBH) is a well-described investigational adjunct to systemic chemotherapy for the treatment of advanced malignancies. The hemodynamic consequences of this physiologic state may include tachycardia, which can produce acute myocardial ischemia in patients with coronary artery disease. Ischemic heart disease is currently considered a contraindication to WBH. We chose to investigate the consequences of using a new beta 1-adrenergic antagonist, esmolol, to attempt to control the tachycardia associated with WBH. After institutional approval and patient consent, nine consecutive patients with normal cardiac function presenting for WBH with carboplatin infusion were studied. Along with standard monitors, radial arterial and oximetric thermodilution pulmonary artery catheters were placed. Patients were sedated and heated in a radiant warmer (Enthermics). Spontaneous ventilation was maintained and hemodynamic data were gathered at 37 degrees C, and at 41.8 degrees C (before, during and after esmolol infusion). Heart rate and cardiac output increased (by 46% (p = 0.001) and 35% (p = 0.04) respectively) while mean arterial pressure and systemic vascular resistance fell (by 18% (p = 0.02) and 44% (p = 0.006) respectively) during hyperthermia. Heart rate was significantly reduced during esmolol administration (mean dose 180 micrograms/kg/min) in the absence of changes in cardiac index and calculated oxygen delivery. Ventricular filling pressures and stroke work were unchanged. No heart failure, pulmonary edema, or other adverse event was observed. Hemodynamic changes seen during esmolol administration were completely reversed 15 min after the infusion was stopped. We conclude that the administration of moderate doses of esmolol is safe for this population of patients undergoing WBH, and that this technique raises the question of whether patients with ischemic heart disease could safely undergo WBH.

Effects of the alpha-/beta-blocking agent carvedilol on hepatic and systemic hemodynamics in patients with cirrhosis and portal hypertension

To enhance the portal hypotensive effect of nonselective beta-blockers, combinations of vasoactive agents with different mechanisms should be considered. The effect of carvedilol (CAS 72956-09-3, Artist), and alpha-/beta-blocking agent, on hepatic and systemic hemodynamics in 10 patients with portal hypertension was evaluated. After administration of carvedilol, the hepatic venous pressure gradient (HVPG) decreased from 15.9 +/- 3.2 mmHg to 13.3 +/- 4.0 mmHg (mean +/- SD) at 60 min (-15%) and to 12.9 +/- 3.0 mmHg at 90 min (-17%, p < 0.05). However, only 5 patients showed a decrease of HVPG by more than 20% at 60 or 90 min. The estimated hepatic blood flow (EHBF) was not significantly reduced. In contrast, heart rate (-8%, p < 0.05), mean arterial pressure (-10%, p < 0.01), and cardiac index (CI) (-8%, p < 0.05) were all reduced at 90 min, while total systemic vascular resistance was not altered. The reduction of HVPG was significantly correlated with the decrease of CI (r = 0.6415, p < 0.05). The portal hypotensive effect of carvedilol may mainly result from a reduction of CI. However, because of the greater reduction of HVPG than that of CI, other additive actions were suggested.

Effects of beta-blocker therapy on mortality in patients with heart failure. A systematic overview of randomized controlled trials

AIMS

Several randomized trials have reported that beta-blocker therapy improves left ventricular function and reduces the rate of hospitalization in patients with congestive heart failure. However, most trials were individually too small to assess reliably the effects of treatment on mortality. In these circumstances a systematic overview of all trials of beta-blocker therapy in patients with congestive heart failure may provide the most reliable guide to treatment effects.

METHODS AND RESULTS

Details were sought from all completed randomized trials of oral beta-blocker therapy in patients with heart failure of any aetiology. In particular, data on mortality were sought from all randomized patients for the scheduled treatment period. The typical effect of treatment on mortality was estimated from an overview in which the results of all individual trials were combined using standard statistical methods. Twenty-four randomized trials, involving 3141 patients with stable congestive heart failure were identified. Complete data on mortality were obtained from all studies, and a total of 297 deaths were documented during an average of 13 months of follow-up. Overall, there was a 31% reduction in the odds of death among patients assigned a beta-blocker (95% confidence interval 11 to 46%, 2P = 0.0035), representing an absolute reduction in mean annual mortality from 9.7% to 7.5%. The effects on mortality of vasodilating beta-blockers (47% reduction SD 15), principally carvedilol, were non-significantly greater (2P = 0.09) than those of standard agents (18% reduction SD 15), principally metoprolol.

CONCLUSIONS

Beta-blocker therapy is likely to reduce mortality in patients with heart failure. However, large-scale, long-term randomized trials are still required to confirm and quantify more precisely the benefit suggested by this overview.

Nonselective beta-adrenergic blockade with carvedilol does not hinder the benefits of exercise training in patients with congestive heart failure

BACKGROUND

Long-term beta-adrenergic blockade does not appear to be associated with drug-induced training in patients with congestive heart failure (CHF); whether exercise training can increase peak aerobic capacity in patients with CHF who are treated with beta-adrenergic blockers is currently unknown.

METHODS AND RESULTS

We studied 23 patients with CHF who were treated with carvedilol or propranolol in addition to ACE inhibitors, furosemide, and digoxin. Of the patients treated with carvedilol, 8 underwent exercise training and 8 remained sedentary. All 7 patients treated with propranolol underwent exercise training. Peak oxygen consumption (mL.kg-1.min-1) was serially measured in trained and sedentary patients. Peak reactive hyperemia (mL.min-1.100 mL-1) was determined in the calf and forearm immediately before and after 12 weeks of training. The peak oxygen consumption of trained patients treated with either carvedilol or propranolol increased from 12.9 +/- 1.4 to 16.0 +/- 1.6 (P < .001) and 12.4 +/- 1.0 to 15.7 +/- 0.9 (P < .001) mL.kg-1.min-1, respectively, whereas it did not change in the sedentary patients. Peak reactive hyperemia increased significantly in the calves but not the forearms of trained patients.

CONCLUSIONS

Long-term, nonselective beta-adrenergic blockade with carvedilol or propranolol does not prevent patients with CHF from deriving systemic and regional benefits from physical training.

Beta-adrenergic blocking agents in the treatment of congestive heart failure: mechanisms and clinical results

Congestive heart failure is a major public health problem in Western countries. Despite current treatment including angiotensin converting enzyme inhibitors, mortality and morbidity remain high. The sympathetic nervous system is markedly activated in heart failure, and inhibition of this system with the beta-adrenergic blocking agents may provide further benefit. Several clinical trials involving over 3,000 patients have shown that beta-blocker therapy improves left ventricular function in patients with heart failure. However, the effects of such therapy on symptoms and exercise tolerance have been variable. Recent reports have suggested that survival is improved with the beta-blocker carvedilol. Large-scale, long-term clinical trials are required to confirm these findings and to clearly define the role of this promising therapy for patients with heart failure.

Carvedilol versus verapamil in chronic stable angina: a multicentre trial

OBJECTIVE

In a multicentre, double-blind, parallel group study, the anti-anginal and the anti-ischaemic efficacy of 12 weeks of therapy with the vasodilating beta-adrenoceptor-blocker carvedilol 25 mg b.i.d. was compared with verapamil 120 mg t.i.d.

METHODS

During a 2-week placebo run-in period, patients were required to have two treadmill exercise tests (modified Bruce Protocol) differing by not more than 15% with regard to total exercise time (TET). Of 313 patients enrolled, 248 were randomized and 212 completed the study according to the protocol.

RESULTS

The primary variable TET was analysed using the Cox Proportional Hazards Model to take into account censored values due to the patient stopping the exercise test for reasons other than angina. Forty-three per cent of patients allocated to carvedilol and 36% to verapamil did not stop with angina at the final visit. There was no difference in the TET between the groups, the risk ratio being 1.14 in favour of carvedilol (90% CI 0.85-1.52). TET increased from 378 s at baseline to 436 s at the final visit in the carvedilol group and from 386 to 438 s in the verapamil group. Results for time to angina and time to 1 mm ST-segment depression were similar. Compared to verapamil, carvedilol significantly reduced HR, systolic BP and rate pressure product at peak exercise. Analysis of 48 h Holter monitor data showed a greater reduction of HR and PVCs with carvedilol. Lown grading improved in both groups. Adverse events were reported by 48% (3.2% serious adverse events) of patients taking carvedilol and 58% (5.7% serious adverse events) taking verapamil.

CONCLUSION

Carvedilol is at least as effective as verapamil in the management of chronic stable angina and demonstrated a favourable adverse event profile.

Carvedilol inhibits clinical progression in patients with mild symptoms of heart failure. US Carvedilol Heart Failure Study Group

BACKGROUND

We tested the hypothesis that carvedilol inhibits clinical progression in patients with mildly symptomatic heart failure due to left ventricular (LV) systolic dysfunction.

METHODS AND RESULTS

Patients (n = 366) who had mildly symptomatic heart failure with an LV ejection fraction (LVEF) < or = 0.35, had minimal functional impairment (defined as the ability to walk 450 to 550 m on a 6-minute walk test), and were receiving optimal standard therapy, including ACE inhibitors, were randomized double-blind to carvedilol (n = 232) or placebo (n = 134) and followed up for 12 months. The primary end point was clinical progression, defined as death due to heart failure, hospitalization for heart failure, or a sustained increase in heart failure medications. Clinical progression of heart failure occurred in 21% of placebo patients and 11% of carvedilol patients, reflecting a 48% (P = .008) reduction in the primary end point of heart failure progression (relative risk, 0.52; CI, 0.32 to 0.85). This effect of carvedilol was not influenced by sex, age, race, cause of heart failure, or baseline LVEF. Carvedilol also significantly improved several secondary end points, including LVEF, heart failure score, NYHA functional class, and the physician and patient global assessments. Carvedilol reduced all-cause mortality but had no effects on the Minnesota Living With Heart Failure scale, the distance walked in 9 minutes on a self-powered treadmill, or cardiothoracic index. The drug was well tolerated.

CONCLUSIONS

Carvedilol, when added to standard therapy, including an ACE inhibitor, reduces clinical progression in patients who are only mildly symptomatic with well-compensated heart failure.

The association between cardiac events and myocardial ischaemia following thrombolysis in acute myocardial infarction and the impact of carvedilol

The majority of post-myocardial infarction studies with beta-blocking drugs involved earlier generations. Newer drugs of this family with additional vasodilating and free-radical suppression properties, such as carvediol, are now available which may improve the prognosis still further. This double-blind, randomized, placebo-controlled, parallel group study was designed to assess the extent of myocardial ischaemia in clinically stable patients 6 weeks after acute myocardial infarction and thrombolysis, and to determine the influence of carvedilol on ischaemic events during the subsequent 6 months. One hundred and one patients who remained event free at 6 weeks post myocardial infarction underwent rest and exercise thallium-201 (TI-201) imaging. Reversible ischaemia was detected in 70 of the patients and there were 13 events in this group compared to one event in the 31 patients without ischaemia (P = 0.07). Four of the 56 patients on carvedilol and 10 of the 45 on placebo had adverse cardiac events (P = 0.04). In patients with reversible ischaemia carvedilol was more effective in reducing these events than was placebo (P = 0.03). These studies demonstrate that reversible myocardial ischaemia detected by TI-201 imaging is present in a large proportion of clinically stable patients following thrombolysis. In these patients, there is an increased cardiac event rate which is significantly reduced by carvedilol.

Carvedilol produces dose-related improvements in left ventricular function and survival in subjects with chronic heart failure. MOCHA Investigators

BACKGROUND

We conducted a multicenter, placebo-controlled trial designed to establish the efficacy and safety of carvedilol, a "third-generation" beta -blocking agent with vasodilator properties, in chronic heart failure.

METHODS AND RESULTS

Three hundred forty-five subjects with mild to moderate, stable chronic heart failure were randomized to receive treatment with placebo, 6.25 mg BID carvedilol (low-dose group), 12.5 mg BID carvedilol (medium-dose group), or 25 mg BID carvedilol (high-dose group). After a 2- to 4-week up-titration period, subjects remained on study medication for a period of 6 months. The primary efficacy parameter was submaximal exercise measured by two different techniques, the 6-minute corridor walk test and the 9-minute self-powered treadmill test. Carvedilol had no detectable effect on submaximal exercise as measured by either technique. However, carvedilol was associated with dose-related improvements in LV function (by 5, 6, and 8 ejection fraction [EF] units in the low-, medium-, and high-dose carvedilol groups, respectively, compared with 2 EF units with placebo, P < .001 for linear dose response) and survival (respective crude mortality rates of 6.0%, 6.7%, and 1.1% with increasing doses of carvedilol compared with 15.5% in the placebo group, P < .001). When the three carvedilol groups were combined, the all-cause actuarial mortality risk was lowered by 73% in carvedilol-treated subjects (P < .001). Carvedilol also lowered the hospitalization rate (by 58% to 64%, P = .01) and was generally well tolerated.

CONCLUSIONS

In subjects with mild to moderate heart failure from systolic dysfunction, carvedilol produced dose-related improvements in LV function and dose-related reductions in mortality and hospitalization rate.