Beta-blocker Group Research Articles

Comparison of prostaglandin analogue, beta-blockers and prostaglandin analogue/beta-blockers fixed combination in patients with primary open-angle glaucoma

To compare intraocular pressure (IOP)-lowering efficacy of prostaglandin analogue, beta-blocker and prostaglandin analogue/beta-blocker fixed combination ophthalmic solution in patients with open-angle glaucoma. In this prospective, multicentre, randomized clinical trial, 120 qualifying patients received prostaglandin/beta-blocker once daily (n = 40), prostaglandin analogue once daily in the evening (n = 40) or beta-blocker twice daily (n = 40). Efficacy was compared across treatment groups over 1 year. Mean IOP at the first visit in the prostaglandin group was 26.6 mmHg (SD ± 2.0 mmHg), in beta-blockers group was 25.9 mmHg (SD ± 1.7 mmHg) and in prostaglandin/beta-blockers group was 26.3 mmHg (SD ± 2.0 mmHg). Mean IOP at the seventh visit (after 1 year) in the prostaglandin group was 19.8 mmHg (SD ± 1.3 mmHg), in beta-blockers group was 21.3 mmHg (SD ± 1.2 mmHg) and in prostaglandin/beta-blockers group was 18.4 mmHg (SD ± 1.3 mmHg; range: 16.0–21.0 mmHg). There was no statistically significant difference of IOP in both eyes on seventh visit by groups (KW = 113.0, p < 0.0001). Over 1 year of treatment, prostaglandin analogue/beta-blockers produced clinically relevant IOP reductions in patients with open-angle glaucoma that were greater than those produced by either prostaglandin analogue or beta-blockers alone. Prostaglandin analogue/beta-blocker provides both more effective IOP reduction than its components and the benefits of once-daily dosing.

Use of speckle strain to assess left ventricular responses to cardiotoxic chemotherapy and cardioprotection

The variability of ejection fraction (EF) poses a problem in the assessment of left ventricular (LV) function in patients receiving potentially cardiotoxic chemotherapy. We sought to use global longitudinal strain (GLS) to compare LV responses to various cardiotoxic chemotherapy regimens and to examine the response to cardioprotection with beta-blockers (BB) in patients showing subclinical myocardial damage. We studied 159 patients (49 ± 14 year, 127 women) receiving anthracycline (group A, n = 53, 46 ± 17 year), trastuzumab (group T, n = 61, 53 ± 12 year), or trastuzumab after anthracyclines (group AT, n = 45, 46 ± 9 year). LV indices [ejection fraction (EF), mitral annular systolic velocity, and GLS] were measured at baseline and follow-up (7 ± 7 months). Patients who decreased GLS by ≥11% were followed for another 6 months; initiation of BB was at the discretion of the clinician. Anthracycline dose was similar between group A and group AT (213 ± 118 vs. 216 ± 47 mg/m(2), P = 0.85). Although ΔEF was similar among the groups, attenuation of GLS was the greatest in group AT (group A, 0.7 ± 2.8% shortening; T, 1.1 ± 2.7%; and AT, 2.0 ± 2.3%; P = 0.003, after adjustment). Of 52 patients who decreased GLS by ≥-11%, 24 were treated with BB and 28 were not. GLS improved in BB groups (from -17.6 ± 2.3 to -19.8 ± 2.6%, P < 0.001) but not in non-BB groups (from -18.0 ± 2.0 to -19.0 ± 3.0%, P = 0.08). Effects of BB were similar with all regimens. GLS is an effective parameter for identifying systolic dysfunction (which appears worst with combined anthracycline and trastuzumab therapy) and responds to cardioprotection in patients administered beta-blockers.

In vivo confocal microscopy of conjunctiva in preservative‐free timolol 0.1% gel formulation therapy for glaucoma

To evaluate the effects at 1 year of preservative-free timolol gel and preserved timolol eye drops on conjunctiva and tear parameters. Forty patients with primary open-angle glaucoma or ocular hypertension were randomized to the two treatment groups and compared with 20 healthy age-matched controls. Clinical tests (IOP, Schirmer I test, and lacrimal film break-up time BUT) and in vivo conjunctival confocal microscopy (IVCM) were performed in all patients at baseline and after 12 months. IVCM (HRT II Rostock Cornea Module; Heidelberg Engineering GmbH, Heidelberg, Germany) was performed after topical anaesthesia in the four cardinal locations and at the corresponding limbus to analyse conjunctiva cells. The main IVCM outcomes were goblet cell density and epithelial regularity. IVCM and clinical parameters were similar in the three groups at baseline. After 12 months, intra-epithelial goblet cell density was significantly lower in the preserved (48.25 ± 7.70) than in the preservative-free beta-blocker group (86.83 ± 22.17, p < 0.001) and controls (88.9 ± 18.33, p < 0.001). The epithelial layer was significantly more regular in the preserved beta-blocker medication group than in the preservative-free beta-blocker group (p < 0.001) and the control group (p < 0.001). A significant reduction in both Schirmer I and BUT was found in the group of preserved timolol (respectively, 11.3 ± 2.97 and 8.12 ± 0.99) compared with preservative-free timolol (16.8 ± 1.83 and 11.27 ± 1.27, p < 0.001) and controls (17.8 ± 1.87 and 12.10 ± 1.28, p < 0.001). Based on our IVCM data, preservative-free beta-blocker gel induces less changes at ocular surface than preserved beta-blockers, a fact that should be considered to obtain less adverse effects and maximal adherence to treatment in a chronic condition such as glaucoma.

Comparative Effects of Preoperative Angiotensin-converting Enzyme In-hibitor, Statin and Beta-blocker Treatment on Human Internal Mammary Artery Reactivity in Patients with Coronary Artery Disease: A Pilot Study

We investigated the effect of angiotensin-converting enzyme (ACE)- inhibitor, statin, and beta-blocker usage before coronary bypass surgery (CABG) on vascular reactivity of the internal mammary artery (IMA). Patients, who underwent elective CABG were evaluated. Samples of IMA obtained from 22 patients were divided into 4 groups in respect of drugs used by patients before bypass surgery (control group, ACE inhibitor + statin group, ACE inhibitor + statin + beta-blocker group, and ACE inhibitor + beta-blocker group). The discarded, distal end section of IMA was carefully removed, and the vasoreactivity of IMA rings was evaluated in vitro using an organ chamber. Smooth muscle contractile function was tested on artery segments exposed to 10-80 mM KCl and norepinephrine. The endothelial function of IMA rings was assessed with acetylcholine (ACh) and bradykinin, while endothelium-independent vasorelaxation was evaluated by sodium nitroprusside (SNP). Both ACh and bradykinin caused concentration-dependent relaxation in endothelium-intact IMA rings. However, the maximal effect produced by endothelium-dependent agents in all treatment groups was more prominent when compared with the control group. There was no significant difference in the endothelium-dependent relaxation response of IMA between ACE inhibitor + statin, ACE inhibitor + beta-blocker and ACE inhibitor + statin + beta-blocker groups. The vasodilatory potency of SNP was similar in all groups. Similarly, contractile response to KCl or norepinephrine was not significantly different between groups. Use of ACE inhibitors and statins before bypass surgery may influence IMA vasoreactivity by improving endothelial control of vascular tone.

13C cross-polarization magic-angle spinning nuclear magnetic resonance analysis of the solid drug forms with low concentration of an active ingredient-propranolol case

Solid State NMR is a method that could be widely used for analyzing solid state forms of drugs in their original formulations. However, when the concentration of the active pharmaceutical ingredient (API) in the final drug form is low, 13C CP MAS NMR methods using standard parameters are not efficient. An example of this situation is propranolol, an important drug from the group of beta-blockers whose concentration in the final drug form is low (below 10%). Basing on the differences in the CP kinetics and relaxation parameters for propranolol and the excipients the authors suggest the proper set of the CP MAS experimental parameters that would allow one to analyze API even in small concentrations in the solid drug formulations.

Pre-treatment with a sinus node blockade, ivabradine, before coronary CT angiography: A retrospective audit

To evaluate whether a simple pre-treatment regimen of sinus node inhibition by ivabradine taken at home for only 1 day resulted in a lower pre-scanning heart rate (HR) and reduced the need for intravenous beta-blockers (BB) prior to coronary computed tomography angiography (CTA). The pre-treatment regimen for coronary CTA changed from using no medication at home (group 1 patients) to the use of 5 mg ivabradine twice a day (group 2 patients), to using 7.5 mg ivabradine twice a day (group 3 patients). The target HR was the same for groups 1 and 2, but lower for group 3. HRs and the use of intravenous BB before coronary CTA was performed were compared between the study groups. The mean HR immediately before the planned CTA procedure was significantly lower throughout groups 1-3 with values of 70 ± 12.9, 64.9 ± 9.8, and 63.2 ± 10.6 beats/min in groups 1, 2, and 3, respectively (p < 0.001). This resulted in a significantly diminished use of intravenous BB in group 2 (mean 5.1 ± 5.8 mg) compared to group 1 (mean 9 ± 7.6 mg; p = 0.002). The target HR of 65 beats/min was achieved in 37%, 47%, and 61% of groups 1, 2, and 3, respectively (p < 0.0001). In conclusion, the administration of ivabradine tablets at home for only 1 day to patients scheduled for coronary CTA resulted in a significantly lower in-clinic HR and a significantly lower mean use of intravenous BB.

Frequent Change of Intra-group Drug Effect on the Blood Pressure Control and Adaptation of Therapy in Hypertensive Patients

Introduction: In this study, we investigated the effects of frequent and unnecessary change in medication to control of blood pressure. Also we investigated the role of the regular use of drugs in the treatment of hypertension. Patients and Methods: Nine hundred hypertensive patients (509 males and 391 females; mean age 62.4 ± 12.1 years) were evaluated retrospectively. Only the patients taking anti-hypertensives for at least six months were included. Patients' records were examined in terms of anti-hypertensive treatment. Intra-group exchange and use of regularly in anti-hypertensive drugs were investigated. Effects of the change in blood pressure and patient compliance were investigated. Results: When intra-group drug change was examined, rates of drug changes were as follows; angiotensin receptor blocker group, 62.3%; angiotensin converting enzyme group, 55.1%; betablockers group, 39.9%; calcium channel blocker group, 20.9%. While the ratio of non-compliance was 28.7% in the patient group with drug change, it was only 9.3% in the group without change in treatment. Average blood pressure difference was found 6.1 ± 7.6 mmHg and 7.6 ± 7.5 mmHg respectively (p < 0.001). The average number of drug usage with and without change of antihypertensive drug were 2.5 ± 0.87 and 2.2 ± 0.89 (p < 0.001) respectively. Conclusion: In patients under angiotensin converting enzyme inhibitors and angiotensin receptor blocker treatments, intra-group change of medication is common. Frequent intra-group change of anti-hypertensive drugs has negative effects on blood pressure control.

Meta-analysis of randomized controlled trials on magnesium in addition to beta-blocker for prevention of postoperative atrial arrhythmias after coronary artery bypass grafting

BackgroundAtrial arrhythmia (AA) is the most common complication after coronary artery bypass grafting (CABG). Only beta-blockers and amiodarone have been convincingly shown to decrease its incidence. The effectiveness of magnesium on this complication is still controversial. This meta-analysis was performed to evaluate the effect of magnesium as a sole or adjuvant agent in addition to beta-blocker on suppressing postoperative AA after CABG.MethodsWe searched the PubMed, Medline, ISI Web of Knowledge, Cochrane library databases and online clinical trial database up to May 2012. We used random effects model when there was significant heterogeneity between trials and fixed effects model when heterogeneity was negligible.ResultsFive randomized controlled trials were identified, enrolling a total of 1251 patients. The combination of magnesium and beta-blocker did not significantly decrease the incidence of postoperative AA after CABG versus beta-blocker alone (odds ratio (OR) 1.12, 95% confidence interval (CI) 0.86-1.47, P = 0.40). Magnesium in addition to beta-blocker did not significantly affect LOS (weighted mean difference −0.14 days of stay, 95% CI −0.58 to 0.29, P = 0.24) or the overall mortality (OR 0.59, 95% CI 0.08-4.56, P = 0.62). However the risk of postoperative adverse events was higher in the combination of magnesium and beta-blocker group than beta-blocker alone (OR 2.80, 95% CI 1.66-4.71, P = 0.0001).ConclusionsThis meta-analysis offers the more definitive evidence against the prophylactic administration of intravenous magnesium for prevention of AA after CABG when beta-blockers are routinely administered, and shows an association with more adverse events in those people who received magnesium.

Invited Commentary

The leading cause of death in the United States remains heart disease. Coronary artery bypass graft (CABG) surgery remains a mainstay therapy in the treatment of this condition. Patients who have coronary artery disease are often smokers and therefore frequently have a concurrent diagnosis of chronic obstructive pulmonary disease (COPD). Published incidence of patients undergoing CABG who also have COPD range from 4% to 27%. Because of the possible bronchoconstrictive effects of beta-blockers, the use of these agents in patients with COPD undergoing CABG has previously been contraindicated. It is well known that the use of beta-blockers in patients undergoing CABG provide both a survival benefit and a protective effect to the development of postoperative atrial fibrillation. This study published by Angeloni and colleagues [1Angeloni E. Melina G. Roscitano A. et al.β-blockers improve survival of patients with chronic obstructive pulmonary disease after coronary artery bypass grafting.Ann Thorac Surg. 2013; 95: 525-532Abstract Full Text Full Text PDF PubMed Scopus (25) Google Scholar] in this issue of The Annals of Thoracic Surgery investigates the long-term survival of patients with COPD undergoing CABG. Patients receiving beta-blockers before and after CABG surgery were compared to those patients who did not receive beta-blockers. Although this was not a randomized controlled trial, the authors attempt to circumvent this limitation by using propensity-matched controls to account for any baseline differences between the groups. At a median follow-up of 36 months, there was a highly significant survival advantage in the beta-blocker group (7.7% deaths) compared to the non–beta-blocker group (18.3% deaths). Surprisingly, there was no difference in the incidence of COPD exacerbations during this time period. This study is the first to compare the effects of beta-blockers on the long-term survival of COPD patients undergoing CABG surgery. Because this study did not stratify based on the severity of COPD, future studies could examine the potential effects of the degree of COPD and outcomes of CABG surgery of patients both with and without beta-blocker therapy. This study carries significant clinical implications for both the preoperative and postoperative management of patients with COPD undergoing CABG. Clinicians providing care for these critically ill patients can prescribe beta-blockers with the knowledge that these medications have significant protective effects on long-term survival without the potential for COPD exacerbations. β-Blockers Improve Survival of Patients With Chronic Obstructive Pulmonary Disease After Coronary Artery Bypass GraftingThe Annals of Thoracic SurgeryVol. 95Issue 2Previewβ-Blockers are known to improve survival of patients with cardiovascular disease, but their administration in patients with chronic obstructive pulmonary disease (COPD) remains controversial. The aim of the present study was to assess the effect of β-blocker administration in patients with COPD undergoing coronary artery bypass grafting. Full-Text PDF

Comparative Effects of Preoperative Angiotensin-converting Enzyme In-hibitor, Statin and Beta-blocker Treatment on Human Internal Mammary Artery Reactivity in Patients with Coronary Artery Disease: A Pilot Study

Purpose: We investigated the effect of angiotensin-converting enzyme (ACE)- inhibitor, statin, and beta-blocker usage before coronary bypass surgery (CABG) on vascular reactivity of the internal mammary artery (IMA). Methods: Patients, who underwent elective CABG were evaluated. Samples of IMA obtained from 22 patients were divided into 4 groups in respect of drugs used by patients before bypass surgery (control group, ACE inhibitor + statin group, ACE inhibitor + statin + beta-blocker group, and ACE inhibitor + beta-blocker group). The discarded, distal end section of IMA was carefully removed, and the vasoreactivity of IMA rings was evaluated in vitro using an organ chamber. Smooth muscle contractile function was tested on artery segments exposed to 10-80 mM KCl and norepinephrine. The endothelial function of IMA rings was assessed with acetylcholine (ACh) and bradykinin, while endothelium-independent vasorelaxation was evaluated by sodium nitroprusside (SNP). Results: Both ACh and bradykinin caused concentration-dependent relaxation in endothelium-intact IMA rings. However, the maximal effect produced by endothelium-dependent agents in all treatment groups was more prominent when compared with the control group. There was no significant difference in the endothelium-dependent relaxation response of IMA between ACE inhibitor + statin, ACE inhibitor + beta-blocker and ACE inhibitor + statin + beta-blocker groups. The vasodilatory potency of SNP was similar in all groups. Similarly, contractile response to KCl or norepinephrine was not significantly different between groups. Conclusion: Use of ACE inhibitors and statins before bypass surgery may influence IMA vasoreactivity by improving endothelial control of vascular tone.

Myocardial protection with prophylactic oral metoprolol during coronary artery bypass grafting surgery: evaluation by troponin I

IntroductionBiochemical markers of myocardial injury are frequently altered after cardiac surgery. So far there is no evidence whether oral beta-blockers may reduce myocardial injury after coronary artery bypass grafting. ObjectiveTo determine if oral administration of prophylactic metoprolol reduces the release of cardiac troponin I in isolated coronary artery bypass grafting, not complicated by new Q waves. MethodsA prospective randomized study, including 68 patients, divided in 2 groups: Group A (n=33, control) and B (n=35, beta-blockers). In group B, metoprolol tartrate was administered 200 mg/day. The myocardial injury was assessed by troponin I with 1 hour and 12 hours after coronary artery bypass grafting. ResultsNo significant difference between groups regarding pre-surgical, surgical, complication in intensive care (15% versus 14%, P=0.92) and the total number of hospital events (21% versus 14%, P=0.45) was observed. The median value of troponin I with 12 hours in the study population was 3.3 ng/ml and was lower in group B than in group A (2.5 ng/ml versus 3.7 ng/ml, P<0,05). In the multivariate analysis, the variables that have shown to be independent predictors of troponin I release after 12 hours were: no beta-blockers administration and number of vessels treated. ConclusionThe results of this study in uncomplicated coronary artery bypass grafting, comparing the postoperative release of troponin I at 12 hours between the control group and who used oral prophylactic metoprolol for at least 72 hours, allow to conclude that there was less myocardial injury in the betablocker group, giving some degree of myocardial protection.

Meta‐analysis of amiodarone versus beta‐blocker as a prophylactic therapy against atrial fibrillation following cardiac surgery

Current guidelines recommend beta-blocker as the first-line preventive treatment of atrial fibrillation (AF) after cardiac surgery; if beta-blocker therapy is contraindicated, then amiodarone is recommended. There is still lack of strong evidence of directly comparing the efficacy of amiodarone and beta-blocker in preventing postoperative AF (POAF). This meta-analysis was to determine whether amiodarione and beta-blocker are equally effective and safe, or one is superior in preventing POAF. We searched the Medline, Web of Science, Cochrane Library databases and clinical trial databases for related articles published from January 1990 to October 2011. The primary outcome was development of AF after cardiac surgery. We used random-effects model when there was significant heterogeneity between trials and fixed-effects method when heterogeneity was negligible. Moreover, subgroup and sensitivity analyses were also performed. We identified totally six trials, which involved 1033 patients. The amiodarone group did not significantly differ from the beta-blocker group in AF occurrence (risk ratio 0.77, 95% confidence interval 0.55 to 1.06, P = 0.11) or the length of hospital stay (weighted mean difference -0.05 day, 95% confidence interval -0.64 to 0.54, P = 0.86). Subgroup analysis stratified by different beta-blockers revealed that amiodarone significantly improved POAF as compared with propranolol. In addition, there was no difference in adverse events after operation. These data indicate that the occurrence of AF and length of hospital stay after surgery are similar in the amiodarone and beta-blocker groups.

베타차단제 복용에 따른 관상동맥질환자의 운동자각도 처방이 운동강도와 안정성에 미치는 영향

The purpose of this study is to investigate effects of rating of perceived exertion (RPE) of patients with coronary artery diseases based on beta blocker administration on exercise intensity and safety. The subjects of this study were patients with coronary artery diseases undergoing medical intervention procedure, who were divided into those who were administered of beta blockers (group A, n=41) and who were not (group B, n=42). They were conducted of exercise stress test, for measuring the HR, the VO2, and RER based on the RPE. The results of this study showed that %HR showed no difference between group A and group B in %HRmax, %VO2max, and %RERmax, when the RPE was 11 (somewhat). The %VO2 was significantly higher in group A than group B (p.05). The RER showed no difference between group A and B. When the RPE was 13 (some hard), the %HR and the %VO2 were significantly higher in group B than A, respectively (p.05). There was no difference in the %RER between the two groups. When the RPE was 15 (hard), the %HR, the %VO2, and the %RER were significantly higher in group B than group A, respectively (p.05). As for the percentage based on the HRR 85% as safety limit of exercise intensity, the exercise intensity showed no difference between A and B when the RPE was 11, while A (82.4±8.3%, 94.0±7.2 %) was significantly higher than B (86.5 ±8.3%, 98.5±5.3%) when the RPE was 13 and 15, respectively (p .05). As for the percentage based on the VO2R85% as safety limit of exercise intensity, the exercise intensity was significantly higher in group B (70.7± 11.1%, 85.7±9.4%) than A (63.4±12.3%, 78.9±10.1%) when the RPE was 13 and 15, respectively (p.05). Conclusively, the RPE 11 was appropriate both for group A and B in the effective limit, but the patients of group A may be recommended to be around 16 scales of the RPE safety limit and those of group B may be recommended to be 15 scales of the RPE.

Effects of Beta-Blocker Use on Volume Status in Hemodialysis Patients

Background: Removal and control of excess fluid with dialysis is considered critical for protection against cardiovascular sequelae. Antihypertensive agents including beta-blockers may influence hemodynamics, which may limit fluid removal during hemodialysis (HD). Methods: Fifty chronic HD patients underwent bioimpedance measurement before and after a midweek dialysis session. Data on volume status, blood pressure, antihypertensive medications, and bioimpedance were analyzed. Results: Patients in the high-volume status group used a significantly higher percentage of beta-blockers than patients in the low-volume status group (54.2 vs. 19.2%, respectively, p = 0.01). Multivariable regression revealed that the use of beta-blockers was independently positively associated with fluid overload (p < 0.05). Intradialytic muscle cramping occurred more often in the beta-blocker group than the control group (44.4 vs. 12.5%, respectively, p = 0.02). Conclusions: Our results suggest that the use of beta-blockers was associated with fluid overload in HD patients, and patients being treated with them experienced more intradialytic muscle cramping during dialysis.

Beta-blocker prevents sudden cardiac death in patients with hemodialysis

BackgroundBeta blockers were shown to prevent SCD in cardiomyopathy or coronary artery disease patients. Dialysis patients show elevated mortality rates, predominantly due to cardiovascular disease. SCD is now one of the leading causes of death in this population. However, the prevention of SCD remains to be elucidated. MethodsWe conducted a retrospective study of 316 patients from a database of all patients undergoing maintenance hemodialysis and followed up for 4.9years. All patients were followed-up until death. Cox regression analysis was used to adjust the hazard ratio for beta blocker use with time until death. ResultsSCD occurred during the study period in 3 (3.8%) patients in the beta blocker group and in 27 (11.4%) patients in the non-beta blocker group (P=0.047). Death from all causes occurred in 15 (18.8%) patients in the beta blocker group and in 97 (41.3%) patients in the non-beta blocker group (P<0.001). Kaplan–Meier curve showed that the rates of both SCD and all-cause death were lower in the beta blocker group (log-rank test, P=0.028 and P<0.001, respectively). In the Cox regression model, beta blocker use was significantly associated with lower adjusted risk of SCD (multivariate adjusted hazard ratio, 0.201; 95% confidence interval, 0.058–0.693; P=0.011). ConclusionIn hemodialysis patients, beta blocker use was associated with lower risks of SCD and death from all causes. Thus, beta blocker use in this high-risk population may substantially improve outcome.

Predictive Value of Microvolt T-Wave Alternans for Cardiac Death or Ventricular Tachyarrhythmic Events in Ischemic and Nonischemic Cardiomyopathy Patients: A Meta-Analysis

Microvolt T-wave alternans (MTWA) has been proposed as a predictor of the risk of ventricular tachyarrhythmias (VT) and sudden cardiac death (SCD). Aim of this study was to perform a systematic review of the literature and a meta-analysis of MTWA in primary prevention patients with ischemic and nonischemic cardiomyopathy. The positive predictive value (PPV), negative predictive value (NPV), and relative risk (RR) of MTWA in predicting death, cardiac death, and SCD during follow-up were reported. Fifteen studies involving 5681 patients (mean age 62 years, mean ejection fraction 32%) were included. The summary PPV during the average 26-month follow-up was 14% (95% CI: 13-15); NPV was 95% (95% CI: 94-96), and the univariate RR was 2.35 (95% CI: 1.68-3.28). The predictive value of MTWA was similar in patients with ischemic and nonischemic cardiomyopathy. The average RR for SCD or VT events of an abnormal MTWA was 2.40, similar to that for cardiac death. When we grouped the studies together depending upon whether beta-blockers were withheld prior to MTWA screening, the beta-blockers group showed an RR of 5.88. By contrast, the group in which beta-blocker therapy was withheld had an RR of 1.63. A positive MTWA determined an approximately 2.5-fold higher risk of cardiac death and life-threatening arrhythmia and showed a very high NPV both in ischemic and nonischemic patients. An abnormal MTWA test was associated with a 5-fold increased risk for cardiac mortality in the low-indeterminate group and about a 6-fold increased risk in beta-blockers group.

The power of large clinical trials

The power of large clinical trials

Risk of new-onset diabetes mellitus associated with beta-blocker treatment for hypertension

Background:This study investigated the risk of new-onset diabetes (NOD) among hypertensive patients initiating carvedilol therapy vs other beta-blocker (BB) therapy in a clinical practice setting.Methods:Patients aged ≥18 years with ≥1 pharmacy claim for a BB of interest (carvedilol immediate-release [IR]/controlled-release [CR], atenolol, metoprolol succinate, or metoprolol tartrate) were identified in the IMS LifeLink Health Plan Claims Database. Index date was the first chronologically occurring prescription for any BB during the enrollment period (July 1, 2000–December 31, 2007). Patients had to be continuously eligible to receive healthcare services 6 months prior to and a minimum of 3 months after index date and have ≥1 diagnostic code for hypertension (ICD-9-CM: 401.xx–405.xx) during this time frame. Patients were excluded for having a diagnosis of diabetes mellitus (ICD-9-CM: 250.xx) and/or prescription for antidiabetic therapy in the 6 months prior to and/or 3 months after index date. Eligible patients were propensity-score matched in a 1:3 ratio (carvedilol : other BBs). Mean duration of follow-up was 12.8 and 14.8 months for the carvedilol group and other BB group, respectively. Primary outcome of interest was presence and timing of NOD.Results:Among 3084 patients in the carvedilol group and 9252 in the other BB group, mean age was 56 years, with 54% male. NOD rate was 3.16 per 100 person-years for carvedilol patients vs 3.36 for patients in the other BB group (NS). Risk of NOD was similar between groups (HR 0.971, 95% CI: 0.78, 1.21; P = 0.792).Conclusions:Findings suggest the risk of NOD among hypertensive patients is similar between carvedilol and other BB agents (i.e., atenolol, metoprolol succinate, or metoprolol tartrate).Limitations:The use of administrative claims data and relatively short follow-up period may limit the generalizability of results.

Effect of beta blockers on central aortic pressure in African-Americans

The objective of this study was to evaluate the vascular effects of heart rate (HR) reduction with BB therapy in African Americans (AA). Beta-blockers (BB) offer less cardiovascular protection than other hypertensive drugs. Studies of Caucasian subjects suggest this may be due to an adverse effect of HR lowering on arterial wave reflection. We studied 506 subjects (age 63 ± 14 years, 52% were treated with BB). Central systolic (C-SBP) and pulse pressure (C-PP), augmented pressure (AP), and augmentation index (AI) were obtained via applanation tonometry (Sphygmocor). On univariate analysis, HR correlated inversely with BB use, C-SBP, AP, and AI (all P < .001), but not P-SBP. Multivariate analysis showed P-SBP and HR to be major determinants of C-SBP (R 2 = 0.95). Generalized linear model analysis showed higher C-SBP ( P < .05) and C-PP ( P = .04), but similar P-SBP ( P = .24) in the BB group. After HR adjustment, differences in C-SBP, C-PP, AI, and AP were attenuated, suggesting HR to be a determinant of C-SBP. BB use is associated with higher C-SBP and lower PPA in hypertensive AA despite similar P-SBP. C-SBP is HR-dependent. HR reduction with BB accounts for less effective central blood pressure control in AA, similar to that reported in Caucasians.

Secondary Preventive Effects of a Calcium Antagonist for Ischemic Heart Attack - Randomized Parallel Comparison With .BETA.-Blockers -

Beta-blockers (BB) have been widely used in the management of hypertension and acute myocardial infarction (AMI), and both national and international guidelines have recommended them as first-line agents. Calcium channel antagonists (CCA) are also effective in the treatment of hypertension and angina pectoris. However, the efficacy of CCA in the prevention of cardiovascular events in post-myocardial infarction (MI) patients in comparison to that of BB remains unclear. A total of 120 post-MI patients (71 patients who were at least 1 month after the onset AMI and 49 stable coronary artery disease patients with a history of MI) were randomly assigned to receive a BB (atenolol, 25-50mg/day, n=60) or a CCA (benidipine, 4-8 mg/day, n=60). All patients with AMI within the previous 1 month or with vasospastic angina were excluded from the present study. The baseline clinical characteristics were generally similar in the BB and CCA groups. The rate of primary composite outcome was 26.3% in the BB group in comparison to 13.3% in the CCA group, with no significant between-group differences (hazard ratio with the CCA group 0.640, P=0.276). Both treatments were well tolerated with few severe adverse events. CCA treatment was found to be as effective as BB in reducing cardiovascular events in post-MI patients.