Biventricular pacing in patients with heart failure and intraventricular conduction delay

In patients with advanced chronic heart failure, characterized by prolonged QRS duration and by decreased cardiac contractility, decreasing dysynchrony by biventricular pacing seems to improve exercise tolerance (6-min walk distance), symptoms (New York Health Association class), and quality of-life scores. Although the results of several reports were consistent, the numbers of patients studied were small, and many of the changes were trends that did not reach statistical significance. The availability of a non-pharmacological treatment that improves exercise capacity and quality-of-life would be a major advance. However, further studies will need to address the question of mortality and morbidity benefits of such intervention.     

Atriobiventricular pacing improves exercise capacity in patients with heart failure and intraventricular conduction delay

OBJECTIVES: We sought to assess the efficacy of biventricular pacing with respect to both peak and submaximal measures of exercise in patients with New York Heart Association class III heart failure (HF) and intraventricular conduction delay in a randomized, blinded study. BACKGROUND: Submaximal and maximal changes in exercise capacity need evaluating in this patient population with this novel therapy. METHODS: Graded exercise and 6-min walk tests were performed in patients randomized to three months each of active (atrio-biventricular) and inactive pacing. Minute ventilation (VE), oxygen uptake (VO(2)), ventilated carbon dioxide (VCO(2)) and heart rate were measured in patients achieving a respiratory quotient >1 (n = 30). Oxygen pulse, anaerobic threshold (AT) and ventilatory efficiency (VE/VCO(2)) were calculated. RESULTS: Active biventricular pacing increased peak VO(2) (15.8 +/- 4.3 vs. 14.4 +/- 4.6 ml/kg/min, p = 0.02), exercise time (501 +/- 223 s vs. 437 +/- 233 s, p < 0.001) and oxygen pulse (9.3 +/- 2.8 vs. 8.1 +/- 3.1 ml/beat, p < 0.01) compared with inactive pacing. The submaximal measures of exercise capacity significantly increased with active pacing: AT (11.2 +/- 4.1 ml/kg/min vs. 9.5 +/- 2.3 ml/kg/min, p = 0.02) and 6-min walk (414 +/- 94 m vs. 359 +/- 94 m, p = 0.001). Minute ventilation/ventilated carbon dioxide improved (32 +/- 9 vs. 36 +/- 11, p = 0.03) with normalization of the VE/VCO(2) slope in 59% of patients (chi-square test, p = 0.002) with active pacing. CONCLUSIONS: Biventricular pacing may improve maximal and submaximal exercise capacity in patients with advanced HF and intraventricular conduction delay.     

Usefulness of bifocal pacing in patients with heart failure and intraventricular conduction delay

BACKGROUND: Bifocal pacing (BFP) has been proposed as a feasible alternative to cardiac resynchronization therapy. AIM: To evaluate BFP in patients with severe heart failure and significant intraventricular conduction delay and to compare it with biventricular pacing (BVP). METHODS: Echocardiographic examination including TDI and invasive measurement of haemodynamics was performed under basal conditions, during BFP and during BVP. RESULTS: Fifty patients were included: 29 with ischaemic heart disease (IHD), 21 with idiopathic dilated cardiomyopathy (IDCM). LV dp/dt(max) increased during BFP compared to the basal state (13.4%, 95% CI 9.2-17.6%, p<0.0001) and a further increase was achieved during BVP (29.5%, 95% CI 23.7-35.4%, p<0.0001). A significant correlation was found between the distance of the right ventricular apical and outflow tract leads and percentage of dp/dt(max) increase in IDCM patients (r=0.72), but not in IHD patients. Interventricular mechanical delay (IVMD) decreased in BFP (43+/-22 ms vs. 53+/-31 ms, p=0.006), but BVP produced even shorter IVMD (22+/-19 ms, p<0.0001). In all patients, regional systolic contraction times were significantly shortened, corresponding with prolongation of the respective regional diastolic filling times during both BFP (p<0.05 for all segments) and BVP (p<0.001 for all segments). CONCLUSIONS: BFP improves LV haemodynamics by decreasing the inter- and intraventricular conduction delays. The leads in the right ventricle should be placed at the longest achievable distance. BVP is superior to BFP.     

双心室起搏治疗慢性心力衰竭伴心室内传导阻滞患者的近期疗效

目的观察双心室起搏治疗慢性心力衰竭（心衰）的临床效果。方法慢性心衰患者13例均伴心室内传导阻滞,体表心电图QRS波时限为146±9 m s,心功能（NYHA）ⅢⅣ级,超声心动图显示左心室射血分数（LVEF）为0.28±0.06,左心室舒张末径（LVEDD）为68±5 mm。患者植入三腔起搏器行心房感知,双心室起搏。结果术后体表心电图QRS波时限缩短至122±7 m s（P<0.01）,心功能平均提高1级。术后1月超声心动图显示LVEF增至0.36±0.06（P<0.05）,舒张期充盈改善,二尖瓣返流减少。结论双心室起搏可有效改善慢性心衰伴心室内传导阻滞患者近期的心功能。     

Ventricular pacing improves exercise tolerance in patients with chronic heart block

Exercise capacity was assessed by means of a simple six minute walking test in a group of 18 patients with heart block whose only presenting symptom was breathlessness. None was in overt cardiac failure. Patients were studied before and after implantation of a transvenous, ventricular, demand pacing system (study group). Eight patients with an implanted pacemaker admitted for elective generator replacement were assessed in the same manner (control group). Exercise capacity in the study group was significantly increased within 48 hours of pacing, and this improvement was maintained in most patients during the follow up period of up to 30 months. In contrast, exercise capacity was unaffected by generator replacement in the control group. Simple ventricular pacing produces symptomatic benefit in patients with heart block accompanied by breathlessness. This benefit is apparent within 48 hours of pacing and is maintained; it can be assessed objectively by a six minute walking test.     

Ventricular pacing improves exercise tolerance in patients with chronic heart block.

Exercise capacity was assessed by means of a simple six minute walking test in a group of 18 patients with heart block whose only presenting symptom was breathlessness. None was in overt cardiac failure. Patients were studied before and after implantation of a transvenous, ventricular, demand pacing system (study group). Eight patients with an implanted pacemaker admitted for elective generator replacement were assessed in the same manner (control group). Exercise capacity in the study group was significantly increased within 48 hours of pacing, and this improvement was maintained in most patients during the follow up period of up to 30 months. In contrast, exercise capacity was unaffected by generator replacement in the control group. Simple ventricular pacing produces symptomatic benefit in patients with heart block accompanied by breathlessness. This benefit is apparent within 48 hours of pacing and is maintained; it can be assessed objectively by a six minute walking test.     

运动康复改善老年慢性心衰患者心功能和生活质量的研究

目的:观察老年慢性心衰患者运动康复后心功能和生活质量的改变.方法:对60例老年慢性心衰病人在常规药物治疗的基础上,实施运动康复疗法,并与58例非康复组进行对照比较;观察出院时病人 6 min步行距离、运动耐量、平均住院日和心功能变化,同时测定血浆脑钠肽(BNP)含量,对其生活质量进行评定;观察随访一年时病人的心功能、再住院率和死亡率.结果:出院时康复组运动贮量、生活质量明显提高,NYHA心功能级别显著改善(P＜0.05或＜0.01),BNP水平和心室重量指数(LVMI)则显著降低(P＜0.05);较之对照组除上述指标显著改善(P＜0.05～＜0.01)外,6 min步行距离增加非常显著(P＜0.01)平均住院日显著减少(P＜0.05);随访一年时康复组病人的心功能、6 min步行距离、运动贮量、生活质量、左室射血分数(LVEF)和E/A比值均明显增加,NYHA心功能级别显著改善(P＜0.01),左房内径(LAd)、LVMI以及再入院率和死亡率明显低于对照组(P＜0.01或P＜0.05).结论:运动康复可以改善心功能,提高运动耐量和生活质量,缩短住院时间,降低再入院率和死亡率;长期运动康复可能有改善心肌的重构的作用.     

运动康复改善老年慢性心衰患者心功能和生活质量的研究

目的:观察老年慢性心衰患者运动康复后心功能和生活质量的改变。方法:对60例老年慢性心衰病人在常规药物治疗的基础上,实施运动康复疗法,并与58例非康复组进行对照比较;观察出院时病人6min步行距离、运动耐量、平均住院日和心功能变化,同时测定血浆脑钠肽(BNP)含量,对其生活质量进行评定;观察随访一年时病人的心功能、再住院率和死亡率。结果:出院时康复组运动贮量、生活质量明显提高,NYHA心功能级别显著改善(P<0.05或<0.01),BNP水平和心室重量指数(LVMI)则显著降低(P<0.05);较之对照组除上述指标显著改善(P<0.05~<0.01)外,6min步行距离增加非常显著(P<0.01)平均住院日显著减少(P<0.05);随访一年时康复组病人的心功能、6min步行距离、运动贮量、生活质量、左室射血分数(LVEF)和E/A比值均明显增加,NYHA心功能级别显著改善(P<0.01),左房内径(LAd)、LVMI以及再入院率和死亡率明显低于对照组(P<0.01或P<0.05)。结论:运动康复可以改善心功能,提高运动耐量和生活质量,缩短住院时间,降低再入院率和死亡率;长期运动康复可能有改善心肌的重构的作用。     

培哚普利联合左卡尼汀对心力衰竭患者运动耐量的影响

目的 探讨培哚普利联合左卡尼汀对心力衰竭患者运动耐量的影响.方法 选择2018年1月至2019年10月于广东省普宁市人民医院药学部进行治疗的心力衰竭患者96例,按照接受药物治疗不同分为2组,每组患者48例.对照组给予培哚普利治疗,观察组给予培哚普利联合左卡尼汀治疗,其余抗心力衰竭治疗措施完全相同.用药结束后3 d,比较...     

Exercise training in heart failure improves quality of life and exercise capacity

Aims Benefit from exercise training in heart failure has mainly beenshown in men with ischaemic disease. We aimed to examine theeffects of exercise training in heart failure patients 75 yearsold of both sexes and with various aetiology. Methods and Results Fifty-four patients with stable mild-to-moderate heart failurewere randomized to exercise or control, and 49 completed thestudy (49% 65 years; 29% women; 24% non-ischaemic aetiology;training, n=22; controls, n=27). The exercise programme consistedof bicycle training at 80% of maximal intensity over a periodof 4 months.Improvements vs controls were found regarding maximalexercise capacity (6±12 vs –4±12% [mean±SD],P<0·01)and global quality-of-life (2 [1] vs 0 [1] units [median {inter-quartilerange}],P<0·01), but not regarding maximal oxygenconsumption or the dyspnoea–fatigue index. All of thesefour variables significantly improved in men with ischaemicaetiology compared with controls (n=11). However, none of thesevariables improved in women with ischaemic aetiology (n=5),or in patients with non-ischaemic aetiology (n=6). The trainingresponse was independent of age, left ventricular systolic function,and maximal oxygen consumption. No training-related adverseeffects were reported. Conclusion Supervised exercise training was safe and beneficial in heartfailure patients 75 years, especially in men with ischaemicaetiology. The effects of exercise training in women and patientswith non-ischaemic aetiology should be further examined.     

Exercise training for heart failure patients improves respiratory muscle endurance,exercise tolerance,breathlessness, and quality of life

PURPOSE: Increased respiratory muscle endurance and peak oxygen consumption (VO(2peak)) induced by respiratory muscle training support the relationship between respiratory muscle function and exercise capacity in patients with heart failure. This raises the question whether exercise-training results in increased respiratory muscle function contributing to an increased exercise tolerance, a decreased perception of breathlessness, and an improved quality of life. METHODS: Prospective cohort analysis was completed on 24 patients with New York Heart Association (NYHA) Class III heart failure [18 men, 6 women; aged = 64 (SD 7.9) years; percent ejection fraction (%EF) = 24.0 (SD 7.8)]. Maximal sustainable ventilatory capacity (MSVC), submaximal and peak exercise responses, perception of breathlessness, and quality of life were measured before (baseline) and after (end of study) 12 weeks of exercise training. RESULTS: As a result of exercise training, VO(2peak) (P=.01) and MSVC (P<.001) increased, with MSVC contributing to a larger proportion of the variability for VO(2peak) at study completion (r=0.57 vs 0.42). Although stroke volume did not increase beyond exercise at 25 W and did not change with exercise training, ventilation decreased during exercise (P<.05), perception of breathing difficulty (P<.05) was reduced, and quality of life was enhanced (P=.008). CONCLUSIONS: Despite no increase in cardiac output and stroke volume, respiratory muscle endurance improved with exercise training, contributing to increased exercise capacity, decreased breathlessness, and decreased perception of breathlessness. Practical implications can include less frequent rest periods and fatigue, greater confidence, maintenance of independence, and enhanced quality of life.     

Enhanced external counterpulsation improves exercise tolerance in patients with chronic heart failure.

OBJECTIVES: The PEECH (Prospective Evaluation of Enhanced External Counterpulsation in Congestive Heart Failure) study assessed the benefits of enhanced external counterpulsation (EECP) in the treatment of patients with mild-to-moderate heart failure (HF). BACKGROUND: Enhanced external counterpulsation reduced angina symptoms and extended time to exercise-induced ischemia in patients with coronary artery disease, angina, and normal left ventricular function. A small pilot study and registry analysis suggested benefits in patients with HF. METHODS: We randomized 187 subjects with mild-to-moderate symptoms of HF to either EECP and protocol-defined pharmacologic therapy (PT) or PT alone. Two co-primary end points were pre-defined: the percentage of subjects with a 60 s or more increase in exercise duration and the percentage of subjects with at least 1.25 ml/min/kg increase in peak volume of oxygen uptake (VO2) at 6 months. RESULTS: By the primary intent-to-treat analysis, 35% of subjects in the EECP group and 25% of control subjects increased exercise time by at least 60 s (p = 0.016) at 6 months. However, there was no between-group difference in peak VO2 changes. New York Heart Association (NYHA) functional class improved in the active treatment group at 1 week (p < 0.01), 3months (p < 0.02), and 6 months (p < 0.01). The Minnesota Living with Heart Failure score improved significantly 1 week (p < 0.02) and 3 months after treatment (p = 0.01). CONCLUSIONS: In this randomized, single-blinded study, EECP improved exercise tolerance, quality of life, and NYHA functional classification without an accompanying increase in peak VO2.