Comparison of sublingual isosorbide dinitrate and Valsalva maneuver for detection of obstruction in hypertrophic cardiomyopathy

Introduction

A left ventricular outflow tract (LVOT) obstruction assessment with a provoking test should be a routine part of the evaluation of patients with hypertrophic cardiomyopathy (HCM). The aim of this study was to compare the utility of the Valsalva maneuver (VM) and sublingual spray application of isosorbide dinitrate (ISDN) for detection of an obstruction.

Material and methods

We prospectively evaluated 81 consecutive HCM patients without severe rest LVOT obstruction (defined as peak rest pressure gradient (PG) ≥ 50 mm Hg). We measured PG at rest, during the VM, after sublingual ISDN spray, and during the VM after ISDN. An obstruction was defined as a PG ≥ 30 mm Hg.

Results

An obstruction was present in 15 patients (19%) at rest (median and interquartile range of PG 16 (7–26) mm Hg), in 38 patients (47%) during the VM (PG 28 (12–49) mm Hg), in 50 (62%) patients after ISDN (PG 50 (12–79) mm Hg), and in 55 patients (68%) during the VM after ISDN (PG 59 (20–87) mm Hg). The difference in occurrence of obstruction among different provoking tests was statistically significant for all comparisons (p < 0.001, except for the comparison of the ISDN test with the VM during ISDN, p = 0.025).

Conclusions

The ISDN test and the VM are useful screening methods for the detection of an HCM obstruction. Although ISDN appears to be more precise than the VM, the best option is a combination of both methods, which maximizes inducement of LVOT obstruction in patients with HCM.     

实时三维超声评价冠状动脉性心脏病患者左室收缩功能及同步性研究

目的探讨实时三维超声(RT-3DE)评价冠状动脉性心脏病(以下简称冠心病)患者左室收缩功能及同步性的应用价值。方法 61例健康志愿者(正常组)及67例冠心病患者(冠心病组)分别进行实时三维超声和常规超声检查,分析比较各种方法所测左室整体、局部收缩功能参数及同步性参数。结果 RT-3DE与双平面Simpson’s法的相关性高于其与M型超声的相关性。RT-3DE估测左室容积低于常规超声。RT-3DE测量从基底段至心尖段容积呈递减趋势,射血分数呈递增趋势;冠心病组的梗死节段左室整体舒张末期容积和整体收缩末期容积均高于正常组相应节段,各节段射血分数均低于正常组相应节段(均P0.05)。冠心病组左室16节段从QRS波起点到最小收缩容积时间的标准差和最大差值(Tmsv 16-SD、Tmsv 16-Dif),以及用R-R间期校正后的Tmsv 16-SD%、Tmsv 16-Dif%均显著高于正常组,且多支病变患者均高于单支病变(均P0.05)。结论 RT-3DE能更加精准、客观地评价冠心病患者左室收缩功能及同步性。     

斑点追踪二尖瓣环位移成像技术评估精神分裂症患者左心收缩功能

目的：应用二维斑点追踪成像(Two-dimensional speckle tracking imaging,2D-STI)组织二尖瓣瓣环位移(Tissue mitral annular displacement, TMAD)技术评估精神分裂症患者左心收缩功能。方法研究对象为精神分裂症患者83例(病例组),70例健康志愿者（对照组）。应用常规超声心动图检查,简易双平面Simpson法测量左室射血分数(Left ventricular ejection fraction,LVEF),应用Qlab9.0工作站,自动获取二尖瓣瓣环4个位点收缩期向心尖方向的最大位移TMAD、二尖瓣瓣环连线中点最大位移(TMADMidpt)及其占左室舒张末期长径的百分比(TMAD Midpt%)的均值进行t检验分析,并与LVEF进行Pearson相关分析。结果病例组与对照组LVEF差异无统计学意义(P>0.05)。与对照组比较,病例组的TMAD、TMADMidpt、TMAD Midpt%均降低,差异有统计学意义(P<0.05)。两组LVEF与TMAD、TMADMidpt、TMAD Midpt%有相关性(对照组：r=0.643、0.663、0.707;病例组：r=0.620、0.634、0.663;P均<0.001)。结论 TMAD指标可较敏感反映精神分裂症患者早期左室收缩功能变化,STI技术测定二尖瓣瓣环位移在精神分裂症患者的心功能评估中具有一定的价值。     

不同联律间期室性期前收缩刺激对窦性心率震荡的影响

目的观察不同联律间期室性期前收缩刺激对窦性心率震荡的影响。方法对20例阵发性室上性心动过速（PSVT）患者,分别通过动态心电图行自发性心率震荡检测和通过心室程序刺激行诱发性心率震荡检测,比较不同联律间期室性期前收缩刺激所诱发的窦性心率震荡参数[震荡初始（TO）和震荡斜率（TS）]的差异。结果自发性窦性心率震荡[（-2.29±1.47）%、（10.14±5.71）ms/R-R]与诱发性窦性心率震荡[（-1.71±1.36）%、（7.12±4.68）ms/R-R]比较,差异均无统计学意义（均P＞0.05）,右心室心尖部、右心室流出道室性期前收缩的联律间期与诱发性窦性心率震荡参数TO和TS均有较好的相关性（r＝-0.825、-0.793、-0.712、-0.689,P＜0.01）。结论诱发性窦性心率震荡与自发性窦性心率震荡具有一致性,心室不同刺激部位对诱发性窦性心率震荡结果无明显影响,室性期前收缩的联律间期与诱发性窦性心率震荡参数有相关性,动态心电图记录中心室不同部位和不同联律间期的室性期前收缩所计算的心率震荡参数值均有较高的可信度。     

Omega-3多不饱和脂肪酸抗心律失常作用及其机制研究进展

越来越多的研究表明,n-3多不饱和脂肪酸（n-3PUFAs）能降低心率,提高心率变异性,减少室性心律失常的发生,预防心源性猝死及减少心房颤动复发等抗心律失常作用,也有研究发现n-3PUFAs具有致心律失常的作用。本文通过分析n-3PUFAs离子通道作用特点及其抗心律失常作用机制,发现n-3PUFAs干预方式不同,作用机制不完全一样,表明n-3PUFAs在抗心律失常方面具有两面性。     

不同剂量胺碘酮治疗心律失常老年患者的疗效分析

目的观察不同剂量胺碘酮治疗心律失常老年患者的疗效。方法 120例老年心律失常患者随机分为A、B、C三组,分别采用高、中、低剂量的胺碘酮口服治疗,观察两组患者治疗前后心悸、胸闷等症状和动态心电图的变化,并监测三组患者用药后的血药浓度峰值。结果三组患者总有效率分别为82.5%、80.0%、80.0%,三组患者疗效对比差异无统计学意义（P〉0.05）;用药后A组患者的血药浓度峰值明显高于B组和C组,且B组高于C组,差异均具有统计学意义（P〈0.05）;A组和B组起效时间明显短于C组,差异具有统计学意义（P〈0.05）,但A组和B组差异无统计学意义（P〉0.05）。结论口服胺碘酮要根据临床实际疗效,调整负荷量和维持量,以最小的维持量求得最好的疗效。     

Reduced Handgrip Strength as a Marker of Frailty Predicts Clinical Outcomes in Patients With Heart Failure Undergoing Ventricular Assist Device Placement

BackgroundHeart failure (HF) is associated with the derangement of muscle structure and metabolism, contributing to exercise intolerance, frailty, and mortality. Reduced handgrip strength is associated with increased patient frailty and higher morbidity and mortality. We evaluated handgrip strength as a marker of muscle function and frailty for prediction of clinical outcomes after ventricular assist device (VAD) implantation in patients with advanced HF.Methods and ResultsHandgrip strength was measured in 72 patients with advanced HF before VAD implantation (2.3 ± 4.9 days pre-VAD). We analyzed dynamics in handgrip strength, laboratory values, postoperative complications, and mortality. Handgrip strength correlated with serum albumin levels (r = 0.334, P = .004). Compared with baseline, handgrip strength increased post-VAD implantation by 18.2 ± 5.6% at 3 months (n = 29) and 45.5 ± 23.9% at 6 months (n = 27). Patients with a handgrip strength <25% of body weight had an increased risk of mortality, increased postoperative complications, and lower survival after VAD implantation.ConclusionPatients with advanced HF show impaired handgrip strength indicating a global myopathy. Handgrip strength <25% of body weight is associated with higher postoperative complication rates and increased mortality after VAD implantation. Thus, the addition of measures of skeletal muscle function underlying the frailty phenotype to traditional risk markers might have incremental prognostic value in patients undergoing evaluation for VAD placement.