Relevance of Echocardiographic Evaluation of Right Ventricular Function in Patients Undergoing Cardiac Resynchronization Therapy

Aims: Right ventricular (RV) dysfunction is a marker of poor prognosis in heart failure (HF) patients. It is still unclear whether RV function might influence response to cardiac resynchronization therapy (CRT).
Methods: Forty-four consecutive patients with HF, large QRS, and either intraventricular or interventricular dyssynchrony underwent echocardiographic evaluation before, 1 month after, and 6 months after CRT. Response to CRT was considered in case of significant LV reverse remodeling, defined as the occurrence of LV end-systolic volume (LVESV) reduction ≥15% at 6 months.
Results: All echocardiographic indexes of baseline RV function and dimensions were significantly more impaired in nonresponders versus responders to CRT: tricuspid annular plane systolic excursion (TAPSE 15 ± 4 mm vs 20 ± 5 mm, P = 0.001), RV systolic pulmonary artery pressure (RVSP 39 ± 14 mmHg vs 27 ± 8 mmHg, P = 0.02), RV end-diastolic area (RVEDA 23 ± 6 cm² vs 16 ± 3 cm² P < 0.001), RV end-systolic area (RVESA 16 ± 6 cm² vs 8 ± 2 cm², P = 0.001), and RV fractional area change (30 ± 12% vs 48 ± 8%, P < 0.001). All the indexes of RV function significantly correlated with the percentage of LVESV reduction after CRT. Severe RV dysfunction was defined as TAPSE ≤14 mm and the population was stratified into two groups based on baseline TAPSE ≤ or > 14 mm. As compared to those with high TAPSE (n = 30), patients with low TAPSE (n = 14) were less likely to show LV reverse remodeling after CRT (76% vs 14%, P < 0.001).
Conclusions: Our study suggests that RV function significantly affects response to CRT. Poor LV reverse remodeling occurs after CRT in patients with HF having severe RV dysfunction at baseline.     

Doppler Echocardiographic Assessment of the Hemodynamic Benefits of Rate Adaptive AV Delay During Exercise in Paced Patients with Complete Heart Block

To determine if rate adaptation of the atrioventricular (AV) delay (i.e., linearly decreasing the AV interval for increasing sinus rate) improves exercise left ventricular systolic hemodynamics, we performed paired maximal semi-upright bicycle exercise tests (EXTs) on 14 chronotropically competent patients with dual chamber pacemakers. Nine patients with complete AV block (CAVB) and total ventricular pacing dependence during exercise comprised the experimental group. Pacemakers in these patients were programmed randomly to rate adaptive AV delay (AVDR) for one EXT and fixed AV delay (AVDF) for the other EXT. AVDF was 156 msec; AVDR decreased linearly from 156–63 msec from rates of 78–142 beats/min. The other five patients had intact AV conduction and comprised the control group who were exercised in identical fashion while their pacemakers were inhibited throughout exercise io assure reproducibility of hemodynamic measurements between EXTs. Cardiac hemodynamics were calculated using measured Doppler echocardiographic systolic aortic valve flows recorded suprasternally with an independent 2-MHz Doppler transducer during a graded ramp exercise protocol. For analysis, exercise was divided into four phases to compare Doppler measurements at submaximal and maximal levels of exercise, rest, early exercise (1st stage), late exercise (stage preceding peak), and peak. Patients achieved statistically similar heart rates between EXTs at each phase of exercise. Although at lower levels of exercise cardiac hemodynamics did not differ, experimental patients (with CAVB) showed a statistically significant benefit to cardiac output at peak exercise with heart rates of 129 ± 13 beats/min (AVDR: 9.4 ± 2.8 L/min; AVDE: 8.2 ± 2.6 L/min, P = 0.002), stroke volume (AVDR: 74.1 ± 25.6 mL; AVDF: 64.3 ± 24.4 mL, P = 0.0003), and aortic ejection time (AVDR: 253.3 ± 35.7 msec; AVDF: 226.7 ± 35.0 msec, P = 0.002). Duration of exercise, peak rate pressure product, peak aortic flow velocities, and acceleration times did not differ. In contrast, control group patients (intact AV conduction throughout exercise) showed no statistical differences between any hemodynamic parameters measured at any phase of exercise from the first to second exercise test. These data demonstrate that systolic cardiac hemodynamics measured echocardia-graphically at the high heart rates achieved with peak exercise are improved with AVDR compared to AVDF in chronofropically competent patients with complete AV block. This is due primarily to improved stroke volume and a longer systolic ejection time with AV delay rate adaptation.     

Assessment of Resynchronization Therapy on Functional Status and Quality of Life in Patients Requiring an Implantable Defibrillator

Background: The effect of cardiac resynchronization therapy (CRT) on physical function and Quality of Life (QoL) in patients who require an implantable defibrillator but do not meet guideline criteria for CRT has not been studied in detail. Methods and Results: This was a randomized study of 72 patients with high risk of sudden cardiac death, ejection fraction (EF) ≤35%, mild‐to‐moderate heart failure symptoms, and QRS > 120 ms. Patients received a CRT defibrillator and were randomized to CRT turned ON or OFF. Objective and subjective measures were performed at baseline and after 6 months. There was no difference in change in left ventricular end‐systolic volume (ESV) by radionuclid angiogram scan, the primary endpoint, between the CRT ON group (ΔESV =?7 ± 52 mL), and CRT OFF group (ΔESV =?30 ± 47 mL). Similarly, echocardiogram measures of ESV and EF showed no difference between the two groups. In the CRT ON group, selected measures of QoL and subjective exercise tolerance but not heart failure symptoms improved significantly. Six‐minute walk distance prolonged in the CRT ON group (baseline 313.6 ± 114.4 m, 6‐month 365.0 ± 122.5 m, P = 0.01), but the difference in change in walk distance between the two groups was not significant. Conclusion: Further studies with larger sample size and longer follow‐up will be required to allow definite conclusions regarding the potential benefit of CRT in this patient population.     

Clinical Significance of Global Wasted Work in Patients with Heart Failure Receiving Cardiac Resynchronization Therapy

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Benefits of a Quadripolar Left Ventricular Lead in Patients Undergoing Cardiac Resynchronization Therapy with Underlying Myocardial Scar

We present a case of a 76‐year‐old man with ischemic cardiomyopathy. Cardiac magnetic resonance imaging demonstrated severe left ventricular (LV) impairment with possibility of scar formation. Cardiac resynchronization therapy was employed with the aid of a novel quadripolar LV lead. The quadripolar LV lead can be programmed for 10 different pacing configurations, allowing the electrophysiologist freedom to optimize the vector around scar and also avoid phrenic nerve stimulation without the requirement of LV lead repositioning. (PACE 2013; 36:e45–e47)     

Superior Cardiac Hemodynamics of Atrioventricular Synchrony Over Rate Responsive Pacing at Submaximal Exercise: Observations in Activity Sensing DDDR Pacemakers

LAU, C.-P., ET AL.: Superior Cardiac Hemodynamics of Atrioventricular Synchrony Over Rate Responsive Pacing at Submaximal Exercise: Observations in Activity Sensing DDDR Pacemakers. The relative hemodynamic profile between dual chamber pacing (DDD) and activity sensing rate responsive pacing (VVIR) was compared in ten patients with dual chamber rate responsive pacemakers (Synergist 11). With a double blind, randomized exercise protocol, DDDR pacemakers were programmed into VVI, VVIR, and DDD (AV interval 150 msec) modes and in seven patients the test in the DDD mode was repeated with the AV interval programmed at 75 msec. A treadmill exercise test of 6-minutes duration (2 stages, Stage 1 at 2 mph, 0% gradient and Stage II at 2 mph, 15% gradient) was performed at each of the programmed settings, with a rest period of 30 minutes in between tests. Cardiac output was assessed using continuous-wave Doppler sampling ascending aortic flow and expressed as a percentage of the value achieved during VVI pacing. During exercise, pacing rate between DDD and VVIR pacing was similar but was higher with DDD at the first minute of recovery (91 ± 4vs 81 ± 3 beat/min, respectively). Cardiac output was significantly higher at rest, during low level exercise, and recovery with DDD pacing compared with VVIR pacing (resting: 21 ± 14 vs -2 ± 7%; Stage I: 36 ± 6 vs 16 ± 7%; Stage II: 25 ± 15 vs 10 ± 8%; recovery: 26 ± 12 vs 4 ± 9%; p < 0.05 in all cases). Systolic blood pressure was significantly higher during low level of exercise in the DDD mode. Shortening of the AV interval to 75 msec did not significantly affect cardiac output during exercise, but cardiac output after exercise was reduced (2 ± 6 vs 23 ± 6% at an AV interval of 150 msec, p < 0.02). By enhancing the stroke volume, DDD pacing improves cardiac hemodynamics at rest, during low level exercise, and early postexercise recovery.     

超声心动图结合二维应变评价左室再同步化治疗慢性心力衰竭患者的短期疗效

目的:应用二维应变超声心动图评价慢性心力衰竭(chronic heart failure,CHF)患者在安装三腔起搏器进行左室再同步化治疗(cardiac resynchronization therapy,CRT)后的短期疗效。方法:选择行植入CRT的患者31例,分别在CRT术前、术后2周及术后3个月测量左室射血分数(left ventricular ejection fraction,LVEF)、左室舒张末内径(left ventricular end-dia-stolic diameter,LVEDD)、左室收缩末内径(left ventricular end-systolic diameter,LVESD),应用二维应变成像技术分析左室壁16个节段的径向应变(radial strain,RS)峰值、环向应变(circumferential strain,CS)峰值及纵向收缩期(longitudinal systolic strain,LS)峰值。结果:与术前相比,术后2周及术后3个月的LVEDD、LVESD和LVEF及左室壁16个节段的RS峰值、CS峰值和LS峰值均有不同程度改善。术后2周与术后3个月相比,LVEDD、LVESD、LVEF及左室壁16个节段的LS峰值差异均有统计学意义,而RS峰值与CS峰值差异均无统计学意义。术后2周及术后3个月心脏同步性均较术前有显著改善。结论:二维超声技术能定量检测CRT后心脏结构变化的数据。CRT术后可逆转心室重构,改善CHF患者的心功能。     

多普勒组织显像、组织同步显像及组织追踪技术评价心脏同步起搏治疗充血性心力衰减的疗效

目的应用多普勒组织显像(DTI)、组织同步显像(TSI)和组织追踪技术(TT)评价心脏同步起搏治疗充血性心力衰减的疗效。方法采用DTI、TSI和TT技术,在ECG监测下起搏器开放和关闭时采集12例充血性心力衰减患者的心尖四腔心、心尖二腔心及心尖长轴观的二维及TVI图像,脱机分析左室EF、左室纵向延迟收缩(DLCs)的比例、QRS距左室各节段收缩速度峰值时间的标准差(Ts-SD),QRS距左室各节段舒张早期速度峰值时间的标准差(Td-SD),二尖瓣瓣环平均收缩速度峰值(LV-Sm),四腔心切面右室侧壁瓣环收缩速度峰值(RV-Sm),并根据组织同步成像图的色彩半定量心室不同步指数,比较每位患者起搏器启闭时各参数变化,并比较Ts与TSI指数的相关性。结果左室收缩功能指标LVEF由起搏关闭时(35.25±11.36)%增高至(44.42±9.93)%(P<0.001),LV-Sm由(3.41±0.65)cm/s增高至(4.79±0.98)cm/s(P<0.001)。右室收缩功能指标RV-Sm由(6.79±1.82)cm/s增高至(7.74±1.90)cm/s(P<0.001)。左室机械不同步指标DLCs比例由起搏器关闭时(35.16±6.41)%降低至(20.31±10.36)%(P<0.001),Ts-SD由(95.17±40.56)ms下降至(54.86±19.42)ms(P<0.01),Td-SD由(87.16±20.51)ms下降至(59.52±29.90)ms(P<0.05),TSI指数由2.13±0.15下降至1.62±0.32(P<0.001)。Ts值的变     

运动疗法改善抑郁症患者社会功能及生活质量的效果

目的研究运动疗法对住院抑郁症患者病情、社会功能及生活质量的影响。方法2013年8月至2014年4月便利选取重庆市精神卫生中心抑郁症患者70例,采用随机数字表法将其分为研究组及对照组各35例,对照组采用抗抑郁药物治疗合并常规护理,研究组在此基础上配合运动疗法,采用汉密尔顿抑郁量表(Hamilton rating scale for depression,HRSD)、生活质量综合评定问卷(generic quality of life inventory-74,GQOLI-74)、社会功能缺陷筛选量表(social function defect screening scale,SDSS)比较两组患者治疗前后抑郁症状、社会功能及生活质量的改善情况。结果治疗第4、8周末,两组患者HRSD得分均低于治疗前;治疗第8周末,研究组HRSD得分低于对照组同期,差异均有统计学意义(均P0.01)。治疗第4、8周末,两组患者的SDSS评分及GQOLI-74各维度评分均低于治疗前,研究组SDSS评分及GQOLI-74各维度评分低于对照组同期,差异均有统计学意义(P0.01或P0.05)。结论运动疗法能显著改善抑郁症患者的病情及社会功能,提高其生活质量。     

恶性骨肿瘤化疗患者生活质量及其影响因素

目的对恶性骨肿瘤化疗患者生活质量进行调查,并分析其影响因素。方法便利抽样选取恶性骨肿瘤化疗患者120例,使用欧洲癌症研究与治疗组织(European Organization for Research and Treatment of Cancer,EQRTC)研制的癌症患者生活质量核心问卷第3版(quality of life-core 30questionnaire version 3.0,QLQ-C30V3.0)对其生活质量进行调查和分析。结果患者生活质量明显低于一般人群(均P0.01);随着化疗次数的增多,患者生存质量各功能领域越来越好,症状体验逐渐减轻,但在化疗最后阶段症状有轻微加重;年龄、职业、是否手术、化疗次数、化疗方案、是否安装假肢、功能锻炼是生活质量的主要影响因素(均P0.05)。结论恶性骨肿瘤化疗患者生活质量处于较低水平,影响因素是多方面的,护理人员应针对主要影响因素采取积极应对措施,从而改善患者的生活质量。