高血压左心室肥厚患者的心肌缺血和室性心律失常

为探讨高血压左心室肥厚（ＨＬＶＨ）患者心肌缺血情况以及心肌缺血与室性心律失常的关系。对９３例超声确定的ＨＬＶＨ病人行动静态９９ｍＴｃ－ＭＩＢＩ心肌断层显像，２４小时动态心电图检查，其中６９例行运动心电图（ＥＥＣＧ）检查，８例行冠状动脉造影。年龄，性别相配的４９例单纯性高血压病（ＳＨＴ）病人作对照。结果：（１）ＨＬＶＨ患者有４１．９％病人伴心肌缺血，其中６４．１％为无症状性心肌缺血。（２）左室重量指数（ＬＶＭＩ）和年龄在单纯ＨＬＶＨ组（ＳＬＶＨ）与ＨＬＶＨ伴缺血组（ＬＶＨＩ）之间没有统计学上的差异，调整性别因素影响，两者仍无差异。（３）ＨＬＶＨ组复杂室性早搏（ＣＶＡ）发生率明显比ＳＨＴ组高，而ＳＬＶＨ组与ＳＨＴ组相比，ＣＶＡ发生率无差异，ＬＶＨＩ组ＣＶＡ发生率明显比ＳＬＶＨ组与ＳＨＴ组高。（４）ＬＶＨＩ组内ＣＶＡ发生与无ＣＶＡ两亚组间年龄和ＬＶＭＩ无显著差异。结论：ＨＬＶＨ患者心肌缺血发生率达４１．９％，而且大部分为无症状性心肌缺血；其ＣＶＡ发生率主要与心肌缺血存在及程度相关；左心室肥厚程度在心肌缺血及ＣＶＡ发生中不起重要作用     

左室肥厚和胰岛素敏感性降低对高血压病患者冠状动脉血流储备的…

为研究高血压左心室肥厚病人的冠状动脉血流储备（ＣＦＲ）与胰岛素敏感性降低（ＤＩＳ）的关系。经食管超声（ＴＥＥ）研究２０例正常人（ＮＳ），３２例高血压非左室肥厚病人（ＨＴ＋ｎｏｎＬＶＨ），３３例高血压左室肥厚病人（ＨＴ＋ＬＶＨ）的ＣＦＲ，用正常血糖胰岛素钳夹技术测定胰岛素敏感性。结果显示：（１）ＨＴ＋ＬＶＨ组Ｄ／Ｒ ＰＤＶ，Ｄ／Ｒ ＰＳＶ（１．７４±０．３７，１．６７±０．４１）较ＨＴ－ｎｏｎＬＶＨ     

老年收缩期高血压左室肥厚与心肌缺血,室性心律失常和心 …

目的：探讨老年收缩期高血压左室肥厚与心肌缺血、心律失常、心衰间的相关性。方法：以动态心电图和超声心动图分别检测６８例老年收缩期高血压左室肥厚（ＨＬＶＨ）患者及３０例老年单纯收缩期高血压（ＳＨＴ）患者的心肌供血、心律和心功能。结果：ＨＬＶＨ组心肌缺血、室性早搏的发生率显著高于ＳＨＴ组;左室收缩功能障碍组ＬＶＥＦ,ＣＩ明显减低;左室舒张功能障碍组二尖瓣舒张早期流速（Ｅ峰）、Ｅ／Ａ、舒张早期减速度显著减     

老年患者心肌缺血和左心室肥大时的心率变异性分析

目的观察老年患者心肌缺血（ＭＩ）和左心室肥大（ＬＶＨ）时心脏自主神经张力的变化。方法对７３例老年冠心病、高血压性心脏病和原发性高血压患者与３０例健康老年人的心率变异性进行分析。结果患者组与对照组除低频（ＬＦ）外，其余参数差异均有显著性（Ｐ＜０．０５）；而不同疾病组间比较，差异均无显著性（Ｐ＞０．０５）；患者组伴有ＭＩ和ＬＶＨ与无ＭＩ和ＬＶＨ患者比较，Ｒ－Ｒ间期均方根（ｒＭＳＳＤ）、Ｒ－Ｒ间期差值＞５０ｍｓ（ＰＮＮ５０）、高频（ＨＦ）和ＬＦ／ＨＦ比值等参数差异有显著性（Ｐ＜０．０５）；无ＭＩ和ＬＶＨ患者与对照组比较，除ＨＦ（Ｐ＜０．０５）外，其余参数差异均无显著性（Ｐ＞０．０５）。结论迷走神经活性减低、交感神经活性增强是导致老年患者心率变异性减低的主要原因，ＭＩ和ＬＶＨ是引起心脏自主神经张力平衡失调的重要因素     

QT间期离散度与左心室肥厚的关系及依那普利对其影响

目的：探讨ＱＴ间期离散度（ＱＴｄ）与左心室肥厚的关系及依那普利治疗对其的影响。方法：选择高血压病（ＥＨ）患者５７例，其中合并左心室肥厚（ＬＶＨ）者（ＥＨ＋ＬＶＨ组）３０例，无合并左心室肥厚者（ＥＨ－ＬＶＨ组）２７例；正常对照者（正常对照组）２４例。用超声心动图仪检测法求得左心室重量，同时从心电图上测得ＱＴｄ与校正后ＱＴｄ（ＱＴｃｄ）。ＥＨ＋ＬＶＨ组患者用依那普利治疗６个月。结果：①ＥＨ＋ＬＶＨ组患者ＱＴｄ与ＱＴｃｄ明显大于ＥＨ－ＬＶＨ组和正常对照组，而ＥＨ－ＬＶＨ组和正常对照组间无显著性差异；②ＱＴｄ和ＱＴｃｄ与左心室重量呈显著正相关（ｒ＝０．７５，Ｐ＜０．０５及ｒ＝０．６１，Ｐ＜０．０５）；③治疗６个月后，ＱＴｄ和ＱＴｃｄ、左心室重量均降低，且ＱＴｄ缩小程度（ΔＱＴｄ）、ＱＴｃｄ缩小程度（ΔＱＴｃｄ）与左心室重量减轻程度（ΔＬＶＭ）亦呈显著正相关。结论：左心室肥厚是高血压病患者ＱＴｄ增大的主要原因；ＱＴｄ可作为左心室肥厚程度的评估指标；依那普利能有效逆转左心室肥厚，减小ＱＴｄ。     

放射性核素造影对无症状心肌缺血的诊断及心功能评价

作者采用ＢＡＩＲＤ－７７系统多晶体γ相机作首次通过法核素心血管造影，对１８例正常人和４０例确诊冠心病伴无症状心肌缺血患者进行检测。结果表明:①静息左室射血分数（ＬＶＥＦ）小于５０％同时伴有室壁运动（ＷＭ）异常者为诊断标准，阳性率在心绞痛伴静息性心肌缺血（ＳＭＩ）组为６０．８％，急性及陈旧性心梗（ＡＭＩ及ＯＭＩ）后分别为８３．３％及６０．０％。②对２３例心绞痛伴ＳＭＩ与１２例ＡＭＩ后ＳＭＩ各项左心室功能参数与正常对照组比较，均提示有不同程度的损害。③局部室壁运动障碍在ＡＭＩ后ＳＭＩ达８３％。ＯＭＩ后ＳＭＩ达８０％，心绞痛伴ＳＭＩ达６０．８％。④ＬＶＥＦ＜３０％同时伴有ＷＭ或局部射血分数图像阳性表现，肺血通过时间延长者，在心肌梗塞患者中．提示可能有右室梗塞。     

放射性核素造影对无症状心肌缺血的诊断及心功能评价

作者采用ＢＡＩＲＤ－７７系统多晶体γ相机作首次通过法核素心血管造影。对１８例正常人和４０例确诊冠心病伴无症状心肌缺血患者进行检测。结果表明：①静息左室射血分数（ＬＶＥＦ）小于５０％同时伴有室壁运动（ＷＭ）异常者为诊断标准，阳性率在心绞痛伴静息性心肌缺血（ＳＭＩ）组为６０．８％，急性及陈旧性心梗（ＡＭＩ及ＯＭＩ）后分别为８３．３％及６０．０％。②对２３例心绞痛伴ＳＭＩ与１２例ＡＭＴ后ＳＭＴ各项左心室     

原发性高血压伴左心室肥厚病人的胰岛素抵抗和红细胞内钙离子代谢

目的比较原发性高血压（ＥＨ）伴左心室肥厚（ＬＶＨ）和无ＬＶＨ病人各３０例的胰岛素抵抗（ＩＲ）和细胞内游离钙浓度（［Ｃａ２＋］ｉ）的变化。用口服葡萄糖前后血浆胰岛素浓度（Ｉ）和Ｉ与血糖（Ｇ）比值来判断ＩＲ。用Ｆｕｒａ－２荧光染料测定红细胞内Ｃａ２＋。结果（１）ＬＶＨ糖负荷后的Ｉ及Ｉ／Ｇ均显著高于ＬＶＨ（－）；（２）ＬＶＨ的红细胞内Ｃａ２＋在空腹和糖负荷后均显著高于ＬＶＨ（－）；（３）ＬＶＨ的左心室重量指数（ＬＶＭＩ）与Ｉ及Ｉ／Ｇ呈正相关，ＬＶＨ（－）的ＬＶＭＩ仅与糖负荷后１ｈ的Ｉ及Ｉ／Ｇ正相关，ＬＶＨ和ＬＶＨ（－）两组的ＬＶＭＩ与红细胞内Ｃａ２＋正相关。结论ＥＨ病人伴ＬＶＨ时ＩＲ和红细胞内Ｃａ２＋增加。     

血管紧张素转换酶基因多态性与高血压左室肥厚的关系

目的探讨血管紧张素转换酶（ＡＣＥ）基因多态性与高血压左室肥厚的关系。方法对１０４例高血压病患者，采用二维引导下的Ｍ型超声心动图检测有无左室肥厚（ＬＶＨ），同时作２４小时动态血压监测，采血检测ＡＣＥ基因多态性（ＰＣＲ方法）。１１３例正常人作基因频率检测。结果（１）高血压ＬＶＨ（＋）与ＬＶＨ（－）两组动态血压指标除夜间平均ＳＢＰ、平均动脉压（ＭＡＰ）差异有显著性外，２４小时及白天平均ＳＢＰ、ＤＢＰ、ＭＡＰ和夜间平均ＤＢＰ两组间差异均无显著性。（２）ＬＶＨ（＋）组Ｉ基因频率明显高于ＬＶＨ（－）组，ＬＶＨ（＋）组Ｉ基因型明显高于ＬＶＨ（－）组。（３）１１３例正常人基因型频率分布：Ｉ为０．５８，Ｄ为０．４２。结论本研究提示，ＡＣＥ基因多态性与左室肥厚明显相关，Ｉ基因型者似更易发生左室肥厚。ＡＣＥ基因型频率分布东方人与西方人不同。     

左室舒张性心功能障碍超声左心形态、功能及运动耐量的改变50例分析

对核素心血池扫描证实的５０例左室舒张性心功能障碍（ＬＶＤＤ）病例、２６例左室收缩性心功能障碍（ＬＶＳＨＦ）病例进行Ｍ型、二维、多普勒超声心动图及活动平板运动试验检测，并以２０例正常人为对照组（ＣＧ）。结果表明：（１）左心形态学改变：与ＬＶＳＨＦ组比较，ＬＶＤＤ组左房内径（ＬＡＤ）、左室内径（ＬＶＤ）无明显增加，室间隔厚度（ＩＶＳＴ）、左室后壁厚度（ＰＷＴ）增加。与ＣＧ组比较，ＬＶＤＤ组ＬＡＤ、ＩＶＳＴ、ＰＷＴ增加，但ＬＶＤ差异无显著性。（２）ＬＶＤＤ组收缩功能指标：左室射血分数（ＬＶＥＦ）、心脏指数（ＣＩ）与ＣＧ组比较差异无显著性，ＬＶＳＨＦ组与ＣＧ组比较，ＬＶＳＨＦ组ＬＶＥＦ、ＣＩ减低。与ＣＧ组比较，ＬＶＤＤ组左室舒张功能指标：二尖瓣舒张早期流速峰值（ＥＰＦＶ）、二尖瓣舒张早、晚期流速峰值比（Ｅ／Ａ）、舒张早期减速度（ＤＣ）比ＣＧ组减低，二尖瓣舒张晚期流速峰值（ＡＰＦＶ）、等容舒张时间（ＩＲＴ）较ＣＧ组增高。ＬＶＤＤ组各左室舒张功能指标与ＬＶＳＨＦ组差异无显著性。（３）ＬＶＤＤ组运动时间、运动当量显著低于ＣＧ组，但高于ＬＶＳＨＦ组。     

Cardiac and Paracardiac Masses: Complementary Role of Echocardiography and Magnetic Resonance Imaging

The objective of this study was to compare the roles of echocardiography and magnetic resonance imaging (MRI) in the evaluation of patients suspected of having cardiac and paracardiac masses. Echocardiography is a widely available and useful technique for characterizing cardiac and paracardiac abnormalities but suffers from a limited field of view and restricted acoustic access to mediastinal structures. MRI is an alternative noninvasive imaging technique for investigation of these abnormalities. Fourteen consecutive patients suspected of having cardiac or paracardiac masses on echocardiography were referred for cardiac MRI. MRI gave more complete visualization in four patients with infiltrating lung tumors and in one patient with intracardiac metastases who had a technically inadequate echo. Echo showed a rapidly moving Chiari network not seen on MRI. Both echo and MRI were helpful in patients with hiatal hernias (2); lipomatous hypertrophy of the interatrial septum (2); left atrial myxoma (1); and calcified mitral annulus (3). We conclude that echocardiography and MRI should be used together to investigate patients with cardiac and paracardiac masses.     

Cardiac imaging in Ebstein anomaly

Ebstein anomaly is a congenital disorder of right ventricular myocardial development, which affects the tricuspid valve in addition to the right ventricular myocardium. Cardiac imaging by transthoracic echocardiography and cardiac magnetic resonance imaging are the key modalities used to assess timing and type of surgery. In this article, we review the current standards of echocardiographic and magnetic resonance imaging in Ebstein anomaly.     

Real-Time Cardiac Catheter Navigation on Three-Dimensional CT Images

Introduction: Targets for ablation of atrial fibrillation, atrial flutter, and non-idiopathic ventricular tachycardia are increasingly being selected based on anatomic considerations. Because fluoroscopy provides only limited information about the relationship between catheter positions and cardiac structures, and is associated with radiation risk, other approaches to mapping may be beneficial. Methods: The spatial and temporal information of an electromagnetic catheter tip position sensing system (Magellan, Biosense Inc.) was superimposed on a three-dimensional (3D) CT of the chest in swine using fiducial markers for image registration. Position and orientation of a 6 French catheter with an electromagnetic sensor was displayed in real-time on a corresponding 3D-CT. Catheter navigation within the heart and the great vessels was guided by detailed knowledge about catheter location in relation to cardiac anatomy. Results: Anatomic structures including the atrial septum, pulmonary veins, and valvular apparatus were easily identified and used to direct catheter navigation. During the right heart examination, the catheter was navigated through the superior and inferior vena cava to predetermined anatomic locations in right atrium, right ventricle and pulmonary artery. The ablation catheter was also navigated successfully from the aorta through the aortic valve in the left ventricle. No complication was encountered during the experiments. The accuracy and precision of this novel approach to mapping was 4.69 ± 1.70 mm and 2.22 ± 0.69 mm, respectively. Conclusions: Real-time display of catheter position and orientation on 3D-CT scans allows accurate and precise catheter navigation in the heart. The detailed anatomic information may improve anatomically based procedures like pulmonary vein ablation and has the potential to decrease radiation times.     

Cardiac morphology for the millennial cardiology fellow: Nomenclature and advances in morphologic imaging

Cardiology fellows‐in‐training, both in adult and pediatric hospitals, need structured education in regards to congenital heart disease (CHD) nomenclature. With improved survival of patients with CHD, it is not uncommon for these patients to seek care in multiple adult and pediatric hospitals. A deep understanding of CHD nomenclature would aid in providing accurate medical and surgical care for these patients. In this forum, we share our experience with such structured education and also comment on recent advances in morphologic imaging that would aid in understanding the nomenclature.     

Imaging Cardiac Stem Cell Transplantation Using Radionuclide Labeling Techniques: Clinical Applications and Future Directions

Stem cell therapy is emerging as a potential new therapy for patients with advanced heart failure. In recent years, advances in molecular imaging have allowed monitoring of stem cell homing and survival. In this review article, we will discuss the clinical application and future directions of stem cell imaging in advanced heart failure.