Patients Receiving Beta-blocker Therapy Research Articles

Left atrial dysfunction can independently predict exercise capacity in patients with chronic heart failure who use beta-blockers

BackgroundBeta-blockers are first-line clinical drugs for the treatment of chronic heart failure (CHF). In the guidelines for cardiac rehabilitation, patients with heart failure who do or do not receive beta-blocker therapy have different reference thresholds for maximal oxygen uptake (VO2max). It has been reported that left atrial (LA) strain can be used to predict VO2max in patients with heart failure, which can be used to assess exercise capacity. However, most existing studies included patients who did not receive beta-blocker therapy, which could have a heterogeneous influence on the conclusions. For the vast majority of CHF patients receiving beta-blockers, the exact relationship between LA strain parameters and exercise capacity is unclear.MethodsThis cross-sectional study enrolled 73 patients with CHF who received beta-blockers. All patients underwent a thorough resting echocardiogram and a cardiopulmonary exercise test to obtain VO2max, which was used to reflect exercise capacity.ResultsLA reservoir strain, LA maximum volume index (LAVImax), LA minimum volume index (LAVImin) (P < 0.0001) and LA booster strain (P < 0.01) were all significantly correlated with VO2max, and LA conduit strain was significantly correlated with VO2max (P < 0.05) after adjusting for sex, age, and body mass index. LA reservoir strain, LAVImax, LAVImin (P < 0.001), and LA booster strain (P < 0.05) were significantly correlated with VO2max after adjusting for left ventricular ejection fraction, the ratio of transmitral E velocity to tissue Doppler mitral annulus e′ velocity (E/e′), and tricuspid annular plane systolic excursion. LA reservoir strain with a cutoff value of 24.9% had a sensitivity of 74% and specificity of 63% for the identification of patients with VO2max < 16 mL/kg/min.ConclusionAmong CHF patients receiving beta-blocker therapy, resting LA strain is linearly correlated with exercise capacity. LA reservoir strain is a robust independent predictor of reduced exercise capacity among all resting echocardiography parameters.Clinical Trial registration: This study is a part of the Baduanjin-Eight-Silken-Movement with Self-efficacy Building for Patients with Chronic Heart Failure (BESMILE-HF) trial NCT03180320 (ClinicalTrials.gov, registration date: 08/06/2017).

ARNI effects in HFrEF. Risk reduction beyond LVEF

Abstract Background The imbalance of cardiac autonomic nervous system function plays an important role in heart failure associated mortality. ARNI has demonstrated a paramount effect in reducing risk of death and hospitalization for worsening of heart failure. However, its exact mechanism of action remains only partly understood. We sought to prospectively compare heart rate variability as a noninvasive measure of cardiac autonomic nervous system function. Methods The study design was prospective sequential observational. Patients served as their own internal control. Patients with heart failure with reduced ejection fraction (HFrEF) receiving optimal medical therapy who were scheduled for a switch to ARNI therapy underwent echocardiography and a standardized 30-minute 12-lead Holter ECG recording before starting ARNI therapy. A monitoring of the parameters was performed 3 months after the start of therapy. Physicians were instructed to increase ARNI dose to the highest tolerated or maximum dose. Besides left ventricular ejection fraction (LVEF) we assessed heart rate (HR), standard deviation of normal-to-normal intervals (SDNN) and mean square of differences between consecutive R-R intervals (RMSSD). Results We recruited 55 patients and baseline characteristics were as follows: age 65±12 years, male sex 78%, NT-proBNP 4989±809 pg/ml, LVEF 28±6%, HR 75±9 bpm, SDNN 43±2 ms, RMSSD 19±2 ms. All patients received beta-blocker therapy and the dosage was similar at baseline and follow-up. After 3 months of ARNI therapy, heart rate showed a significant reduction of 7% (74±14 bpm vs. 69±11 min, P=0.005). SDNN increased by 49% (43±2 ms vs. 64±4 ms, P&amp;lt;0.001) and RMSSD by 42% (19±2 ms vs. 27±3 ms, P=0.01). These results were accompanied by increased LVEF (28±6% vs. 38±10%, P&amp;lt;0.001) and reduced plasma NT-proBNP levels (4989±809 pg/ml vs. 2602±87 pg/ml, P&amp;lt;0.04). NYHA Class of affected patients changed from III to II. Conclusion After changing from ACE/AT1-I to ARNI, significant improvement of autonomic cardiac nervous system function could be observed. ARNI apparently activates the parasympathetic nervous system as suggested by decreased HR and increased SDNN and RMSSD. Therefore, part of its cardioprotective and beneficial effects may relate to the restoration of autonomic cardiac nervous system function. Potential beneficial effects regarding incidence of sudden cardiac arrest may relate to these observations. Funding Acknowledgement Type of funding sources: None.

Impact Of Preoperative Beta-blockade On Outcomes Following The Surgical Treatment Of Atherosclerotic Disease

INTRODUCTION AND OBJECTIVES Beta-blockers are integral to the treatment of many cardiovascular diseases however studies of their potential perioperative benefit remain mixed in their findings. The objective of this study was to determine the impact of preoperative beta-blockade in patients undergoing vascular surgery to treat atherosclerotic disease (carotid endarterectomies and supra- and infra-inguinal bypasses). METHODS The National Surgical Quality Improvement Program (NSQIP) targeted datasets were queried for patients undergoing carotid endarterectomies and supra- and infra-inguinal bypasses between 2011-2019. Rates of major adverse cardiovascular events (MACE) including myocardial infarction (MI), stroke and death were compared between patients with and without preoperative beta-blockade (BB). Multivariable logistic regression models were created to adjust for differences in baseline characteristics between groups. RESULTS Of the 84,331 patients included, 56% received BB. Beta-blocker use has decreased from 59.7% in 2011 to 53.9% in 2019 (p<.001). Patients receiving BB were more likely to have diabetes (45% vs 32%, p<0.001), heart failure (4% vs 1%, p<0.001), or be on an anti-hypertensive medication (93% vs 69%, p<0.001). Unadjusted rates of death (1.5% vs 0.96%, p<0.001) and MACE (4.2% vs 2.7%, p<0.001) were higher in the BB group. After adjusting for differences in baseline characteristics, BB was associated with an increased risk of MACE (OR=1.24, 95%CI=1.14-1.34). On subgroup analysis, BB was associated with increased risk of MACE following carotid endarterectomy (OR=1.31, 95%CI=1.15-1.49), infra-inguinal bypass (OR 1.191, 95%CI=1.05-1.34), and supra-inguinal bypass (OR 1.252, 95%CI=1.035-1.514). BB was associated with increased risk of MACE following open procedures (OR=1.29, 95%CI=1.17-1.41), but not endovascular procedures. CONCLUSIONS Preoperative beta-blockade is associated with an increased risk of MACE following common vascular surgery procedures, even after controlling for baseline health status, which affects over half of patients undergoing surgical treatment of atherosclerotic disease. Risk of MACE in patients receiving beta-blocker therapy may be lessened by endovascular approach. Beta-blockers are integral to the treatment of many cardiovascular diseases however studies of their potential perioperative benefit remain mixed in their findings. The objective of this study was to determine the impact of preoperative beta-blockade in patients undergoing vascular surgery to treat atherosclerotic disease (carotid endarterectomies and supra- and infra-inguinal bypasses). The National Surgical Quality Improvement Program (NSQIP) targeted datasets were queried for patients undergoing carotid endarterectomies and supra- and infra-inguinal bypasses between 2011-2019. Rates of major adverse cardiovascular events (MACE) including myocardial infarction (MI), stroke and death were compared between patients with and without preoperative beta-blockade (BB). Multivariable logistic regression models were created to adjust for differences in baseline characteristics between groups. Of the 84,331 patients included, 56% received BB. Beta-blocker use has decreased from 59.7% in 2011 to 53.9% in 2019 (p<.001). Patients receiving BB were more likely to have diabetes (45% vs 32%, p<0.001), heart failure (4% vs 1%, p<0.001), or be on an anti-hypertensive medication (93% vs 69%, p<0.001). Unadjusted rates of death (1.5% vs 0.96%, p<0.001) and MACE (4.2% vs 2.7%, p<0.001) were higher in the BB group. After adjusting for differences in baseline characteristics, BB was associated with an increased risk of MACE (OR=1.24, 95%CI=1.14-1.34). On subgroup analysis, BB was associated with increased risk of MACE following carotid endarterectomy (OR=1.31, 95%CI=1.15-1.49), infra-inguinal bypass (OR 1.191, 95%CI=1.05-1.34), and supra-inguinal bypass (OR 1.252, 95%CI=1.035-1.514). BB was associated with increased risk of MACE following open procedures (OR=1.29, 95%CI=1.17-1.41), but not endovascular procedures. Preoperative beta-blockade is associated with an increased risk of MACE following common vascular surgery procedures, even after controlling for baseline health status, which affects over half of patients undergoing surgical treatment of atherosclerotic disease. Risk of MACE in patients receiving beta-blocker therapy may be lessened by endovascular approach.

\u03b2-Adrenergic blockade in patients with dementia and hip fracture is associated with decreased postoperative mortality

PurposeDementia, present in 20% of hip fracture patients, is associated with an almost threefold increase in postoperative mortality risk. These patients have a substantially higher incidence of cardiovascular, respiratory, and cerebrovascular mortality after hip fracture surgery compared to patients without dementia. This study aimed to investigate the association between beta-blocker therapy and postoperative mortality in patients with dementia undergoing hip fracture surgery.MethodsThis nationwide study included all patients in Sweden with the diagnosis of dementia who underwent emergency surgery for a hip fracture between January 2008 and December 2017. Cases where the hip fracture was pathological or conservatively managed were not included. Poisson regression analysis with robust standard errors was performed while controlling for confounders to determine the relationship between beta-blocker therapy and all-cause, as well as cause-specific, postoperative mortality.ResultsA total of 26,549 patients met the study inclusion criteria, of whom 8258 (31%) had ongoing beta-blocker therapy at time of admission. After adjusting for clinically relevant variables, the incidence of postoperative mortality in patients receiving beta-blocker therapy was decreased by 50% at 30 days [adj. IRR (95% CI) 0.50 (0.45–0.54), p < 0.001] and 34% at 90 days [adj. IRR (95% CI) 0.66 (0.62–0.70), p < 0.001]. Cause-specific mortality analysis demonstrated a significant reduction in the incidence of postoperative cardiovascular, respiratory, and cerebrovascular death within 30 and 90 days postoperatively.ConclusionBeta-blocker therapy is associated with decreased postoperative mortality in hip fracture patients with dementia up to 90 days after surgery. This finding warrants further investigation.

Bisoprolol therapy does not reduce right ventricular sympathetic activity in pulmonary arterial hypertension patients.

Right ventricular (RV) function and autonomic dysfunction are important determinants of morbidity and mortality in patients with pulmonary arterial hypertension (PAH). Although successful in animal studies, effects of beta-blocker therapy on RV function in clinical trials were disappointing. To understand this discrepancy, we studied whether beta-blocker therapy changes RV sympathetic activity. Idiopathic PAH (IPAH) patients received beta-blocker therapy (uptitrated to a maximal tolerated dose) and underwent cardiac magnetic resonance imaging, right heart catheterization, and a [11C]-hydroxyephedrine positron emission tomography ([11C]HED PET) scan at baseline to determine, respectively, RV ejection fraction (RVEF), RV pressures, and sympathetic activity. [11C]HED, a norepinephrine analogue, allows determination of sympathetic innervation of the RV. [11C]HED retention index reflects norepinephrine transporter activity. As a consequence of excessive catecholamine levels in the synaptic cleft, this transporter may be downregulated. Therefore, low [11C]HED retention index indicates high sympathetic activity. 13 IPAH patients underwent [11C]HED PET scans at baseline and after bisoprolol treatment. Although heart rate was reduced, systemic modulation of autonomic activity by bisoprolol did not affect local RV sympathetic nerve activity, RV function, or RV wall tension. In PAH patients, RV [11C]HED retention index was lower compared to LV tracer uptake (p<0.01) and was related to systolic wall tension (R2 = 0.4731, p<0.01) and RV function (R2 = 0.44, p = 0.01). In RV failure, the tolerated dosage of bisoprolol did not result in an improvement of RV function nor in a reduction in RV sympathetic activity.

Clinical and genetic profile of congenital long QT syndrome in Hong Kong: a 20-year experience in paediatrics.

Congenital long QT syndrome (LQTS) is a genetically transmitted cardiac channelopathy that can lead to sudden cardiac death. This study aimed to report the clinical and genetic characteristics of all young patients diagnosed with LQTS in the only tertiary paediatric cardiology centre in Hong Kong. This is a retrospective review of all paediatric and young adult patients diagnosed at our centre with LQTS from January 1997 to December 2016. The diagnosis of LQTS was established with a corrected QT interval (QTc) ≥480 ms, Schwartz score of >3 points, or the presence of a pathogenic mutation. Fifty-nine patients (33 males) from 52 families were included, with a mean age of 8.17 years (range, 0.00-16.95 years) at presentation. Five patients had concomitant congenital heart diseases. The mean follow-up duration was 5.33 ± 4.65 years. The mean QTc in the cohort was 504 ± 47 ms. They presented with syncope and convulsion (49%), cardiac arrest (10%), bradycardia and neonatal atrioventricular block (12%). Fifteen (25%) patients were asymptomatic at diagnosis. Thirty-eight (64.4%) patients were confirmed to have a pathogenic mutation for LQTS genes. Forty-five (76.3%) patients received beta blocker therapy. Thirteen (22.0%) patients required implantable cardioverter defibrillator. There was no mortality in the study period. The 1-, 5-, and 10-year breakthrough cardiac event-free rates were 93.0%, 80.7%, and 72.6%, respectively. Identification of the disorder, administration of beta blockers, and lifestyle modification can prevent subsequent cardiac events in LQTS. Genotyping in patients with LQTS is essential in guiding medical therapy and improving prognosis.

Valor del «test de bipedestación» en el diagnóstico y la evaluación de la respuesta al tratamiento con bloqueadores beta en el síndrome de QT largo

Introduction and objectivesPatients with congenital long QT syndrome (LQTS) have an abnormal QT adaptation to sudden changes in heart rate provoked by standing. The present study sought to evaluate the standing test in a cohort of LQTS patients and to assess if this QT maladaptation phenomenon is ameliorated by beta-blocker therapy. MethodsElectrographic assessments were performed at baseline and immediately after standing in 36 LQTS patients (6 LQT1 [17%], 20 LQT2 [56%], 3 LQT7 [8%], 7 unidentified-genotype patients [19%]) and 41 controls. The corrected QT interval (QTc) was measured at baseline (QTcsupine) and immediately after standing (QTcstanding); the QTc change from baseline (ΔQTc) was calculated as QTcstanding – QTcsupine. The test was repeated in 26 patients receiving beta-blocker therapy. ResultsBoth QTcstanding and ΔQTc were significantly higher in the LQTS group than in controls (QTcstanding, 528 ± 46ms vs 420 ± 15ms, P < .0001; ΔQTc, 78 ± 40ms vs 8 ± 13ms, P < .0001). No significant differences were noted between LQT1 and LQT2 patients. Typical ST-T wave patterns appeared after standing in LQTS patients. Receiver operating characteristic curves of QTcstanding and ΔQTc showed a significant increase in diagnostic value compared with the QTcsupine (area under the curve for both, 0.99 vs 0.85; P < .001). Beta-blockers attenuated the response to standing in LQTS patients (QTcstanding, 440 ± 32ms, P < .0001; ΔQTc, 14 ± 16ms, P < .0001). ConclusionsEvaluation of the QTc after the simple maneuver of standing shows a high diagnostic performance and could be important for monitoring the effects of beta-blocker therapy in LQTS patients.Full English text available from: www.revespcardiol.org/en

Value of the “Standing Test” in the Diagnosis and Evaluation of Beta-blocker Therapy Response in Long QT Syndrome

Introduction and objectivesPatients with congenital long QT syndrome (LQTS) have an abnormal QT adaptation to sudden changes in heart rate provoked by standing. The present study sought to evaluate the standing test in a cohort of LQTS patients and to assess if this QT maladaptation phenomenon is ameliorated by beta-blocker therapy. MethodsElectrographic assessments were performed at baseline and immediately after standing in 36 LQTS patients (6 LQT1 [17%], 20 LQT2 [56%], 3 LQT7 [8%], 7 unidentified-genotype patients [19%]) and 41 controls. The corrected QT interval (QTc) was measured at baseline (QTcsupine) and immediately after standing (QTcstanding); the QTc change from baseline (ΔQTc) was calculated as QTcstanding – QTcsupine. The test was repeated in 26 patients receiving beta-blocker therapy. ResultsBoth QTcstanding and ΔQTc were significantly higher in the LQTS group than in controls (QTcstanding, 528 ± 46ms vs 420 ± 15ms, P < .0001; ΔQTc, 78 ± 40ms vs 8 ± 13ms, P < .0001). No significant differences were noted between LQT1 and LQT2 patients. Typical ST-T wave patterns appeared after standing in LQTS patients. Receiver operating characteristic curves of QTcstanding and ΔQTc showed a significant increase in diagnostic value compared with the QTcsupine (area under the curve for both, 0.99 vs 0.85; P < .001). Beta-blockers attenuated the response to standing in LQTS patients (QTcstanding, 440 ± 32ms, P < .0001; ΔQTc, 14 ± 16ms, P < .0001). ConclusionsEvaluation of the QTc after the simple maneuver of standing shows a high diagnostic performance and could be important for monitoring the effects of beta-blocker therapy in LQTS patients.

The use of guideline recommended beta-blocker therapy in primary prevention implantable cardioverter defibrillator patients: insight from Danish nationwide registers.

We aimed to examine the use of guideline recommended beta-blocker therapy prior to and after primary prevention implantable cardioverter defibrillator (ICD) implantation in a 'real-life' setting. From the Danish Pacemaker and ICD Registry we identified all 1st-time primary prevention ICD and cardiac resynchronization therapy defibrillator (CRT-D) implantations in Denmark from 2007-12 (n = 2935). Use of beta-blocker, type and dose was acquired through the Danish Prescription Registry. According to guideline recommendations, we defined target daily doses as ≥50 mg carvedilol and ≥200 mg metoprolol. Prior to implantation 2427 of 2935 (83%) patients received beta-blocker therapy, with 2166 patients (89%) having initiated treatment 3 months or more prior to implantation. The majority of patients was prescribed carvedilol (52%) or metoprolol (41%). Patients on carvedilol reached target dosages more frequently than patients on metoprolol, with 39% of patients on carvedilol and 26% of patients on metoprolol at the time of implantation (P < 0.001 for all time-points). Increase in proportion of patients reaching target daily doses was observed for both carvedilol and metoprolol after ICD implantation. Carvedilol treatment was a strong predictor for being on target dose of BB at time of implant, as was treatment with angiotensin-converting enzyme inhibitors and/or spironolactone, no history of myocardial infarction, younger age and less pronounced heart failure symptoms. In a real-life setting of primary prevention ICD patients, 39% and 26% of patients were titrated to optimal target dose of carvedilol or metoprolol prior to implantation. A higher proportion of patients on carvedilol reached target dose, as compared with metoprolol.

Effect of beta-blocker therapy on the risk of infections and death after acute stroke--a historical cohort study.

BackgroundInfections are a frequent cause for prolonged hospitalization and increased mortality after stroke. Recent studies revealed a stroke-induced depression of the peripheral immune system associated with an increased susceptibility for infections. In a mice model for stroke, this immunosuppressive effect was reversible after beta-blocker administration. The aim of our study was to investigate the effect of beta-blocker therapy on the risk of infections and death after stroke in humans.Methods625 consecutive patients with ischemic or hemorrhagic stroke, admitted to a university hospital stroke unit, were included in this historical cohort study. The effect of beta-blocker therapy on post-stroke pneumonia, urinary tract infections and death was investigated using multivariable Poisson and Cox regression models.Results553 (88.3%) patients were admitted with ischemic stroke, the remaining 72 (11.7%) had a hemorrhagic stroke. Median baseline NIHSS was 8 (IQR 5–16) points. 301 (48.2%) patients received beta-blocker therapy. There was no difference in the risk of post-stroke pneumonia between patients with and without beta-blocker therapy (Rate Ratio = 1.00, 95%CI 0.77–1.30, p = 0.995). Patients with beta-blocker therapy showed a decreased risk for urinary tract infections (RR = 0.65, 95%CI 0.43–0.98, p = 0.040). 7-days mortality did not differ between groups (Hazard Ratio = 1.36, 95%CI 0.65–2.77, p = 0.425), while patients with beta-blocker therapy showed a higher 30-days mortality (HR = 1.93, 95%CI 1.20–3.10, p = 0.006).ConclusionsBeta-blocker therapy did not reduce the risk for post-stroke pneumonia, but significantly reduced the risk for urinary tract infections. Different immune mechanisms underlying both diseases might explain these findings that need to be confirmed in future studies.

Beta-blocker therapy is not associated with symptoms of depression and anxiety in patients receiving an implantable cardioverter-defibrillator

Beta-blockers are frequently prescribed to implantable cardioverter-defibrillator (ICD) patients. Beta-blocker therapy has been proposed to induce emotional distress such as depression and anxiety, but a paucity of studies has examined the relationship between beta-blockers and distress. We investigated the association between beta-blocker therapy, including type and dosage, and symptoms of anxiety and depression in a consecutive cohort of patients receiving an ICD. Between 2003 and 2010, 448 consecutively implanted ICD patients were enrolled in the prospective Mood and personality as precipitants of arrhythmia in patients with an Implantable cardioverter Defibrillator: A prospective Study (MIDAS), of which 429 completed the Hospital Anxiety and Depression Scale (HADS) and the ICD Patient Concerns questionnaire (ICDC) at baseline. Eighty per cent of all patients received beta-blocker therapy. In univariate analysis, beta-blocker therapy was not significantly associated with symptoms of anxiety, depression, and ICD concerns (β = -0.030, β = 0.007, and β = -0.045, respectively; all P's >0.36). Type of beta-blocker showed a trend towards significance for mean levels of ICD concerns (P = 0.09). No association was found between dosage and emotional distress (all P's >0.21). After adjustment for relevant clinical and demographic variables, the association of beta-blocker therapy and symptoms of anxiety, depression, and ICD concerns remained non-significant (β = 0.009, β = 0.037, and β = 0.019, respectively; all P's >0.47). In patients receiving an ICD, beta-blocker therapy was not associated with symptoms of anxiety, depression, and ICD concerns. Research is warranted that further elucidates the link between beta-blocker therapy and emotional distress in this vulnerable patient group.

Levosimendan may provide a better neurohormonal response in heart failure patients receiving beta blocker therapy — Reply

The hemodynamic effects of levosimendan have been shown to be maintained or even enhanced by beta blockers. Furthermore, levosimendan has recently been reported to represent mortality benefit in patients receiving beta blockers. However, it is not clear whether these favorable effects of levosimendan under beta blockade are also suggested by a better neurohormonal response. We evaluated neurohormonal response to levosimendan in patients receiving beta blocker in our study population on the basis of the comments of Giamouzis and colleagues on previously published article, in which both levosimendan and dobutamine were found to be very effective inotropic agents in achieving favorable neurohormonal response but levosimendan had a better and prolonged effect. The findings of recent subgroup analysis suggested that levosimendan treatment trended toward a greater reduction in NT-proBNP levels and therefore may provide a better neurohormonal response in patients receiving beta blockers as compared with those patients not receiving beta blocker.

Should Major Vascular Surgery Be Delayed Because of Preoperative Cardiac Testing in Intermediate-Risk Patients Receiving Beta-Blocker Therapy With Tight Heart Rate Control?

Should Major Vascular Surgery Be Delayed Because of Preoperative Cardiac Testing in Intermediate-Risk Patients Receiving Beta-Blocker Therapy With Tight Heart Rate Control?

Heart rate recovery – a potential marker of clinical outcomes in heart failure patients receiving beta-blocker therapy

Heart rate recovery (HRR) within the first few minutes of graded exercise has been associated with impaired clinical outcomes in patients being evaluated for coronary artery disease. HRR is abnormal in patients with heart failure (HF), but has not been associated with clinical outcomes in these patients. The objective of the present study was to determine whether HRR following cardiopulmonary exercise testing (CPET) correlates with peak oxygen consumption (VO(2)), and whether it impacts clinical outcomes, including HF hospitalizations and total mortality, or the need for cardiac transplantation. CPET was performed in 78 patients referred to the Montreal Heart Institute (Montreal, Quebec) with congestive HF between January 2000 and December 2002. All patients had New York Heart Association class II or III HF with a left ventricular ejection fraction of 45% or lower. Mean (+/- SD) age was 53+/-11 years and left ventricular ejection fraction was 27+/-9%. Forty-four per cent had ischemic cardiomyopathy, 88% received beta-blockers and 79% received angiotensin-converting enzyme inhibitors. HRR was defined as the difference from peak exercise HR to HR measured at specific time intervals. HRR was calculated 30 s, 60 s, 90 s and 120 s after exercise. Mean peak VO(2) was 18.0+/-5.3 mL/kg/min, resting HR was 74+/-13 beats/min and peak HR was 119+/-22 beats/min. HRR measured was 10+/-9 beats/min after 30 s, 20+/-12 beats/min after 60 s, 25+/-15 beats/min after 90 s and 30+/-13 beats/min after 120 s. At 90 s, patients with an HRR below 24 beats/min were more likely to have an HF hospitalization at five-year follow-up (eight hospitalizations [22.2%] versus two hospitalizations [2.7%]; P=0.0134). There was a correlation between peak VO(2) and HRR 90 s and 120 s after completion of the exercise test (r=0.40 after 90 s, P=0.001, and r=0.41 after 120 s, P=0.008). In patients with HF, blunted HRR 90 s and 120 s after CPET correlate with peak VO(2) and are associated with increased risk of worsening HF. HRR is easily measured and a useful marker for morbidity in patients with HF.

Should Major Vascular Surgery Be Delayed Because of Preoperative Cardiac Testing in Intermediate-Risk Patients Receiving Beta-Blocker Therapy With Tight Heart Rate Control?

Should Major Vascular Surgery Be Delayed Because of Preoperative Cardiac Testing in Intermediate-Risk Patients Receiving Beta-Blocker Therapy With Tight Heart Rate Control?

Should Major Vascular Surgery Be Delayed Because of Preoperative Cardiac Testing in Intermediate-Risk Patients Receiving Beta-Blocker Therapy With Tight Heart Rate Control?

Should Major Vascular Surgery Be Delayed Because of Preoperative Cardiac Testing in Intermediate-Risk Patients Receiving Beta-Blocker Therapy With Tight Heart Rate Control?

Should Major Vascular Surgery Be Delayed Because of Preoperative Cardiac Testing in Intermediate-Risk Patients Receiving Beta-Blocker Therapy With Tight Heart Rate Control?

The purpose of this study was to assess the value of preoperative cardiac testing in intermediate-risk patients receiving beta-blocker therapy with tight heart rate (HR) control scheduled for major vascular surgery. Treatment guidelines of the American College of Cardiology/American Heart Association recommend cardiac testing in these patients to identify subjects at increased risk. This policy delays surgery, even though test results might be redundant and beta-blockers with tight HR control provide sufficient myocardial protection. Furthermore, the benefit of revascularization in high-risk patients is ill-defined. All 1,476 screened patients were stratified into low-risk (0 risk factors), intermediate-risk (1 to 2 risk factors), and high-risk (> or =3 risk factors). All patients received beta-blockers. The 770 intermediate-risk patients were randomly assigned to cardiac stress-testing (n = 386) or no testing. Test results influenced management. In patients with ischemia, physicians aimed to control HR below the ischemic threshold. Those with extensive stress-induced ischemia were considered for revascularization. The primary end point was cardiac death or myocardial infarction at 30-days after surgery. Testing showed no ischemia in 287 patients (74%); limited ischemia in 65 patients (17%), and extensive ischemia in 34 patients (8.8%). Of 34 patients with extensive ischemia, revascularization before surgery was feasible in 12 patients (35%). Patients assigned to no testing had similar incidence of the primary end point as those assigned to testing (1.8% vs. 2.3%; odds ratio [OR] 0.78; 95% confidence interval [CI] 0.28 to 2.1; p = 0.62). The strategy of no testing brought surgery almost 3 weeks forward. Regardless of allocated strategy, patients with a HR <65 beats/min had lower risk than the remaining patients (1.3% vs. 5.2%; OR 0.24; 95% CI 0.09 to 0.66; p = 0.003). Cardiac testing can safely be omitted in intermediate-risk patients, provided that beta-blockers aiming at tight HR control are prescribed.

Pharmacological left ventricular reverse remodeling in elderly patients receiving optimal therapy for chronic heart failure

In recent years, reversal of established left ventricular (LV) dilatation has been increasingly recognized in middle-aged patients with dilated cardiomyopathy receiving angiotensin-converting enzyme (ACE) inhibitors and/or beta-blockers. We performed this prospective study to evaluate whether optimized therapy for heart failure also induces LV reverse remodeling in older patients. One hundred and twenty-four patients aged >70 years with LV ejection fraction <40% underwent clinical and echocardiographic evaluation at baseline and after 1 year. During the early stage of follow-up, pharmacological therapy was optimized. LV reverse remodeling was defined as a reduction in LV end-diastolic volume >25% from baseline to final evaluation. LV reverse remodeling was recognized in 32 patients (26%). Compared to the subjects who did not improve LV geometry, those with reverse remodeling had, at baseline, higher arterial blood pressure, lower serum creatinine levels, shorter duration of symptoms of heart failure, more frequently received beta-blocker therapy and had predominantly nonischemic aetiology. The variables associated with the development of reverse remodeling in the multivariate analysis were shorter duration of symptoms of heart failure (Odds ratio: 7.7; CI: 2.5-23.3, p=0.0001) and beta-blocker therapy (Odds ratio: 6.0; CI: 1.6-23.3, p=0.01). LV reverse remodeling takes place in elderly as well as in younger heart failure patients. A significant proportion of elderly patients undergoes this favourable process which occurs prevalently in patients receiving beta-blocker therapy with a short history of cardiac disease.

Use of cardiac resynchronization therapy to optimize beta-blocker therapy in patients with heart failure and prolonged QRS duration

A retrospective analysis was performed on 52 patients with heart failure to determine the change in beta-blocker therapy after cardiac resynchronization therapy (CRT). After 6 months of CRT, the number of patients receiving beta-blocker therapy increased from 36 to 44, with improved clinical outcomes and larger beta-blocker doses, indicating that these 2 therapies may work together to improve outcomes by allowing the use of larger doses of beta blockers while correcting ventricular dyssynchrony.

Association of long QT syndrome loci and cardiac events among patients treated with beta-blockers.

Data on the efficacy of beta-blockers in the 3 most common genetic long QT syndrome (LQTS) loci are limited. To describe and assess outcome in a large systematically genotyped population of beta-blocker-treated LQTS patients. Consecutive LQTS-genotyped patients (n = 335) in Italy treated with beta-blockers for an average of 5 years. Cardiac events (syncope, ventricular tachycardia/torsades de pointes, cardiac arrest, and sudden cardiac death) while patients received beta-blocker therapy according to genotype. Cardiac events among patients receiving beta-blocker therapy occurred in 19 of 187 (10%) LQT1 patients, 27 of 120 (23%) LQT2 patients, and 9 of 28 (32%) LQT3 patients (P<.001). The risk of cardiac events was higher among LQT2 (adjusted relative risk, 2.81; 95% confidence interval [CI], 1.50-5.27; P =.001) and LQT3 (adjusted relative risk, 4.00; 95% CI, 2.45-8.03; P<.001) patients than among LQT1 patients, suggesting inadequate protection from beta-blocker therapy. Other important predictors of risk were a QT interval corrected for heart rate that was more than 500 ms in patients receiving therapy (adjusted relative risk, 2.01; 95% CI, 1.16-3.51; P =.01) and occurrence of a first cardiac event before the age of 7 years (adjusted RR, 4.34; 95% CI, 2.35-8.03; P<.001). Among patients with genetic LQTS treated with beta-blockers, there is a high rate of cardiac events, particularly among patients with LQT2 and LQT3 genotypes.