单纯右冠状动脉狭窄对左心室功能的影响

目的:探讨单纯右冠状动脉（RCA）狭窄不同狭窄程度和狭窄节段对左心室功能的影响。方法:将冠状动脉造影证实为单纯RCA狭窄的患者99例,按不同狭窄程度、不同狭窄节段和不同冠脉优势型进行分组,并与494例无冠状动脉狭窄的对照组比较,经左心室造影测定的左室射血分数（LVEF）和左室舒张末压（LVEDP）。结果:与对照组患者相比,轻度、中度和重度单纯右RCA狭窄患者的LVEF变化不显著,完全闭塞患者的LVEF显著下降（P<0.05）;右冠中段、右冠远段、后降支和侧后支病变患者的LVEF均无有意义变化,右冠近段病变患者LVEF下降有统计学意义（P<0.05）。单纯RCA狭窄患者中,右冠优势组LVEF略低于均衡优势组和左冠优势组,但差异未达显著水平。单纯RCA狭窄对LVEDP的影响并不明显。结论:单纯RCA主干近段狭窄和单纯RCA完全闭塞对左室收缩功能可产生一定程度的损害。     

Proximal left anterior descending coronary heart disease and complex ventricular arrhythmias

In this study, 87 consecutive patients with angiographically proven coronary artery disease (CAD, stenosis >75%) underwent 24-h Holter monitoring, 76 of them having had transmural myocardial infarction, a mean of five months before evaluation. Of the total, 51 patients showed single-vessel disease, in 31 (61%) of them with involvement of the left anterior descending (LAD) artery. In 26 patients with proximal LAD stenosis or occlusion and usually large aneurysms and subsequently impaired left ventricular function relatively low prevalence of significant ventricular premature contraction (VPC, Lown (III) was seen. On the contrary in 19 patients with multivessel disease and proximal LAD stenosis advanced forms of VPCs were present in 63% (p<0.01). Further both groups differed significantly in the frequency of postinfarction angina (30% vs. 100%; p<0.001) and their incidence in positive exercise stress tests (15% vs. 84%; p<0.001). Ejection fractions were comparable in both groups (mean 45% vs. 52%). Finally 17 patients with multivessel disease but without proximal LAD lesion did not differ in any of the above mentioned parameters, when compared to the patients with single-vessel disease and proximal LAD stenosis. We conclude that impaired left ventricular function does not sufficiently explain the high risk of sudden death in postmyocardial infarction patients. The coronary and functional status of the surviving myocardium has to be taken into consideration as well.     

The effect of coronary artery bypass surgery on ventricular arrhythmias

The effect of coronary artery bypass surgery (CAB) on ventriculararrhythmias (VA) was studied in a prospective investigationinvolving 32 patients (mean age 54 years) who underwent CABbecause of severe stable angina pectoris. Prior to CAB as wellas 12 months later each patient was subjected to the followinginvestigational programme: resting ECG, exercise ECG, 24-h ECG,selective coronary arteriography, ventriculography and cardiaccatheterization. Exercise ECG showed VA in only three patients.The prevalence of VA during 24-h ECG was 56 and 66% on the twooccasions (NS), while complicated VA (multiform, repetitive,R on T) was seen in 18 and 28%, respectively (NS). The persistence(number of 6-h periods showing VA) was 33 and 47% with regardto any VA (P<0.05), while complicated VA occurred in 13 and15% of the 6-h periods (NS). Except for an increase in dp/dt_max/Pat the postoperative measurement (P<0.05), no significantchange in the performance of the left ventricle was seen afterCAB though the graft patency was 77%. It is concluded that inpatients with ‘medically intractable’ stable anginapectoris, CAB does not effect the occurrence of VA to any greatextent — probably because left ventricular function isunchanged one year after as compared with that prior to CAB.     

Submitral left ventricular aneurysm compressing the left main coronary artery

This report describes a 43-yr-old black woman who was referred for evaluation of severe mitral regurgitation. Conventional echocardiography revealed a large submitral left ventricular aneurysm. A selective coronary angiography demonstrated compression of the left main coronary artery by submitral aneurysm. Successful surgical repair was performed. Cathet. Cardiovasc. Diagn. 40:173–175, 1997. © 1997 Wiley-Liss, Inc.     

Radiation-induced stenosis of the left main coronary artery

Isolated left main coronary artery stenosis induced by mediastinal radiation is a well-documented but rare entity. Its clinical manifestations can be latent for many years, but its ominous sequela cannot be ignored. We report here such a patient presenting 16 yr postmediastinal radiation, the longest documented latency to date.     

Prevalence and factors associated with left ventricular remodeling in renal artery stenosis

The objective of this study is to evaluate the prevalence, geometric patterns, and factors associated with left ventricular remodeling in patients with renal artery stenosis (RAS). Demographic, clinical, and echocardiographic data were assessed in 77 patients with RAS prior to endovascular stenting. The left ventricular mass index (LVMI) and relative wall thickness were calculated using American Society of Echocardiography (ASE) recommendations. Patients were classified based on LVMI and relative wall thickness into four ventricular remodeling patterns: normal geometry, concentric remodeling (CR), concentric hypertrophy (CH), and eccentric hypertrophy (EH). Logistic regression was done to investigate the determinants of the different ventricular remodeling patterns. Mean LVMI and relative wall thickness were 118 ± 40 g/m² and 0.45 ± 0.1. Left ventricular hypertrophy was observed in 65%. CH was the most prevalent geometric pattern of remodeling (normal, 16.9%; CR, 18.2%; CH, 40%; EH, 24.6%). Thirty (39%) patients had an abnormal LV systolic function (ejection fraction <55%), with 14 (46%) of them having eccentric hypertrophy. Independent predictor of EH was glomerular filtration rate (odds ratio [OR], 0.943; confidence interval [CI], 0.899–0.989; P = .01). Systolic elevation of blood pressure (OR, 1.030; CI, 1.003–1.058; P = .03) was associated with CH, and elevated diastolic blood pressure was associated with CR (OR, 0.927; CI, 0.867–0.992; P = .02). Patients with RAS have a high prevalence of left ventricular remodeling and LVH. Even though CH was the most prevalent pattern of left ventricular remodeling, EH was commonplace and was associated with renal dysfunction and heart failure.     

右冠状动脉狭窄程度对左冠状动脉狭窄患者左室射血分数的影响

目的研究右冠状动脉不同程度狭窄对左冠状动脉狭窄患者左室射血分数（LVEF）的影响。方法根据左冠状动脉病变部位不同,将1 000例左冠状动脉狭窄患者分为左前降支（LAD）狭窄,左回旋支（LCX）狭窄,左主干（LM）狭窄,左前降支+左回旋支（LAD+LCX）狭窄4个系列。每个系列再根据右冠状动脉（RCA）病变程度不同分为RCA正常组（直径狭窄<50%）、RCA非闭塞组（99%>直径狭窄≥50%）和RCA闭塞组（直径狭窄≥99%）,比较分析3组间LVEF的差异。结果在LAD,LCX,LM,LAD+LCX狭窄时,与RCA正常组LVEF相比,RCA非闭塞组LVEF分别下降0.9%,0.3%,3.4%和2.8%;RCA闭塞组LVEF分别下降10.9%,3.7%,6.5%和5.2%。LAD狭窄时,RCA非闭塞组和RCA闭塞组之间LVEF有统计学差异（P<0.01）。结论右冠状动脉病变可在左冠状动脉狭窄的基础上使左室射血分数进一步下降;当左冠状动脉狭窄为闭塞性病变时,影响更为明显。     

组织多普勒超声评价冠状动脉狭窄患者左心室舒张功能

目的探讨组织多普勒超声评价冠状动脉不同狭窄程度对左心室舒张功能的影响。方法在我院行冠状动脉造影检查的患者219例,根据造影结果分为3组,冠状动脉病变严重组(至少1支血管狭窄≥70%,A组),冠状动脉病变轻微组(血管狭窄70%,B组)和冠状动脉造影检查正常组(C组)。应用超声测量冠心病患者二尖瓣舒张早期血流峰值(E)与组织多普勒成像二尖瓣环舒张早期峰值(Em)的比值(E/Em)。结果 A组的E/Em较B、C组高,差异有统计学意义(P0.05,P0.01),B组与C组比较,E/Em差异无统计学意义(P0.05)。结论E/Em可检测出冠状动脉高度狭窄引起的左心室功能障碍。     

Iatrogenic left main coronary artery stenosis following aortic valve replacement

A case of severe iatrogenic fibrous left main coronary arterystenosis following aortic valve replacement (Hall-Kaster prosthesis)is documented clinically, angiographically and histologically.Reported histological data of this rare complication of valvereplacement are reviewed. The onset of ischaemic symptoms inthe first six months after valve replacement is highly suggestiveof iatrogenic coronary artery stenosis, and urgent coronaryangiography is recommended.     

冠状动脉旁路术与左心室功能关系研究

目的研究冠状动脉旁路术（CABG）术前与术后早期左室功能的变化,并找出其影响因素。方法 103例行CABG术患者,应用心脏彩色多普勒超声测定其术前及术后4～7 d左室射血分数（LVEF）、缩短分数（FS）及二尖瓣血流E峰与A峰的比值（E/A）。结果术后LVEF值、FS值较术前减低（P〈0.01）;术前LVEF值、术前FS值、左前降支狭窄程度、NYHA心功能分级是影响左室功能下降的主要因素。结论 CABG术后早期可出现左室收缩功能下降,为缺血再灌注后的心肌顿抑现象,应积极加以治疗。     

Radionuclide assessment of left ventricular function during dobutamine infusion in patients with coronary artery disease: comparison with ergometer exercise

The effects of dobutamine on left ventricular function were assessed employing radionuclide ventriculography (RNV) in 7 normal subjects (Group 1) and 21 patients with coronary artery disease (Group 2). After routine bicycle ergometer exercise RNV, dobutamine infusion was started at 5 micrograms/kg/min and the dosage was increased by 5 micrograms/kg/min every 4 minutes to a total of 15 micrograms/kg/min. In Group 1, left ventricular ejection fraction (LVEF) increased by both ergometer exercise and dobutamine infusion. In Group 2, LVEF did not increase during exercise, but increased during dobutamine infusion without evidence of significant myocardial ischemia. Only 2 patients in Group 2 had new regional wall motion abnormality. Left ventricular end-diastolic volume (LVEDV) in Group 2 increased from 191 +/- 19 to 210 +/- 18 ml during ergometer exercise, but decreased from 193 +/- 18 to 153 +/- 19 ml during dobutamine infusion. Short-term low-dose infusion of dobutamine may be used in patients without evidence of significant myocardial ischemia, but probably cannot be substituted for exercise testing in patients with mild to moderate coronary artery disease.     

冠状动脉粥样硬化性心脏病伴左心功能不全高危患者的外科治疗

目的总结分析冠状动脉粥样硬化性心脏病（冠心病）伴左心功能不全高危患者行外科治疗的疗效。方法回顾性分析29例高危冠心病伴左心功能不全患者（年龄〉70岁）外科治疗的临床资料,着重分析手术方法和疗效。结果围手术期死亡5例（17.2%,5/29）,均死于严重低心排血量综合征。超声心动图复查示术后左心室舒张期末内径与术前比较明显减小,差异有统计学意义[（54.71±4.91）mm vs.（58.33±3.46）mm,t=3.2442,P〈0.05];左心室射血分数较术前明显提高（45.36%±10.27%vs.32.86%±4.10%,t=6.0873,P〈0.05）。结论对于高龄伴左心功能不全冠心病患者行外科治疗,其手术时机和手术方式的合理选择,围手术期的积极治疗能明显提高术后生存率。     

冠心病心室晚电位与左室功能的关系

目的：观察心室晚电位（ＶＬＰ）、心律失常事件（ＡＥ）与左室功能之间的关系。方法：１４５例冠心病患者均进行信号平均心电图（ＳＡ－ＥＣＧ）检测和２４小时ＨＯＬＴＥＲ监测，同期进行冠状动脉造影和左室造影及随访观察。结果：１１４５例冠心病患者（心绞痛５５例、陈旧性心肌梗死９０例），随访１４１±７１（４－３６）月，发生ＡＥ７例。２ＶＬＰ阳性组左室射血分数（ＬＶＥＦ）显著降低（Ｐ＜００５）。３发生ＡＥ组ＬＶＥＦ显著降低（Ｐ＜００５）。结论：左室功能障碍者ＶＬＰ阳性率高、容易发生ＡＥ。     

Predictors of improvement in left ventricular function after initially successful angioplasty of unprotected left main coronary artery stenoses

BACKGROUND: Percutaneous coronary intervention (PCI) has been increasingly applied to unprotected left main coronary artery (LMCA) lesions, with varied procedural success and clinical outcomes. However, the effect of PCI on left ventricular performance is still unclear, and there are no clinical studies assessing factors that influence left ventricular ejection fraction (LVEF) in these cases. METHODS: Between April 1986 and August 2002, de novo PCI was performed for unprotected LMCA stenoses in 199 patients. Close clinical and angiographic follow-up were conducted after the procedure. RESULTS: One hundred eighty patients survived over six months and analysis of paired left ventriculography was possible in 175 patients. Improvement in LVEF was observed in the entire population (52.9?±?15.7% to 56.1?±?14.3%, p?= 0.048). The LVEF change was 6.7?± 9.5% (p?&lt;?0.01) in group with baseline LVEF?≤??50% and 0.7?±?6.7 % (p?=?NS) in group with LVEF?&gt;?50%. There was significant intergroup difference (p?&lt;?0.001). Patients with baseline diameter stenosis ≥60% had an improvement of 5.3?±?8.3% (p?&lt;?0.05) whereas those with stenosis?&lt;?60% had no improvement (2.0?±?8.4%, p?=?NS). CK-MB elevation ≥3 times normal after PCI had a significant inverse association with improvement in LVEF (p?&lt;?0.05). Multivariate analysis revealed baseline LVEF ≤?50% was the only independent predictor of improvement in LVEF (standard estimate?=?3.509, 95% CI: 2.164-4.854, p?&lt;?0.001). CONCLUSIONS: Successful PCI procedure is associated with significant improvement in LVEF, especially in patients with depressed left ventricular function. (Int J Cardiovasc Intervent 2004; 6: 119-127)     

Left atrial size and left ventricular function in coronary artery disease: An echocardiographic-angiographic correlative study

M-mode echocardiography was used to determine left atrial size in 100 patients with coronary artery disease undergoing cardiac catheterization. Patients were divided in two groups on the basis of left atrial diameter (≥ 40 mm in 40 patients and < 40 mm in 60). Patients with larger left atria had a higher frequency of electrocardiographic evidence of left atrial abnormality (p < 0.01) and myocardial infarction (p < 0.001). Pulmonary capillary wedge and left ventricular end-diastolic pressures were higher (p < 0.005) in patients with larger left atria. An abnormal end-diastolic volume (>100 ml/M²) was observed in 13 patients with enlarged left atria compared to none with normal left atrial size (p < 0.001). Triple vessel disease was more frequent (63% vs 32%) and single vessel disease less frequent (10% vs 37%) in patients with larger left atria (p < 0.005). Abnormal left ventricular contractile patterns were noted in 45% of patients with normal left atrial diameters compared to 80% in those with an enlarged left atrium (p < 0.001). An abnormally low ejection fraction (< 0.5) was observed in 25% and 80%, respectively, in patients with normal and enlarged left atria (p < 0.001). Of 58 patients with normal ejection fractions, only 17% had left atrial diameters ≥40 mm compared to 71% of 42 patients with abnormally low ejection fractions (p < 0.001). Of 18 patients with left atrial diameters > 42 mm, only two had normal ejection fractions. The mean ejection fraction for patients with left atrial diameters <40 mm was 0.63 ± 0.13 compared to 0.41 ± 0.18 for those with diameters ≥40 mm (p < 0.001). The sensitivity, specificity, and predictive value for an enlarged left atrium in identifying an abnormal ejection fraction were, respectively, 71, 83, and 75%. These findings indicate that M-mode echocardiographic left atrial enlargement is a useful marker of advanced hemodynamic and anglographic abnormality in patients with coronary artery disease.     

Therapeutic implications of dynamic coronary stenosis in patients with single vessel coronary artery disease

Ten patients with proven single-vessel coronary artery disease and a positive exercise test for ischaemia were investigated to establish the importance and therapeutic implications of dynamic coronary stenosis in such patients. All patients interrupted their anti-anginal therapy and under took serial exercise testing in an attempt to identify variability in the ischaemic threshold. Ergonovine testing was performed in nine patients and all underwent 48 h of ambulatory ST segment monitoring while treatment was discontinued. Patients then entered a randomized double-blind study of atenolol and nifedipine; treadmill exercise testing and 48 h of ambulatory ST segment monitoring were performed at the end of each treatment phase. Six (60%) patients showed evidence of variability in coronary vasomotor tone four of whom developed significant ST segment changes during administration of ergonovine; a further two had greater than 30% variability in time to onset of ischaemia during serial treadmill exercise testing. Atenolol significantly increased the time to ischaemia on exercise testing, both in the group as a whole and in the subgroup with evidence of altered vasomotor tone when compared with no therapy, and led to a non-significant reduction in the frequency and duration of ischaemia during the patients' daily lives. Nifedipine, conversely, did not significantly increase time to ischaemia on exercise testing or reduce the frequency or duration of ambulatory ischaemia in either the whole group or the subgroup. With evidence of altered vasomotor tone when compared to no therapy however it was beneficial in terms of reduction in chest pain and requirement for glyceryl trinitrate during daily life.(ABSTRACT TRUNCATED AT 250 WORDS)     

Detection of diastolic left ventricular function abnormalities in patients with coronary artery disease and normal systolic function

We angiographically calculated left ventricular (LV) filling in 50 patients, all of whom had normal systolic LV function and 21 (42%) of whom had coronary artery disease. Five volume determinations were made: at end systole (ESV), first third (DV 1/3, half (DV 1/2), and second third of diastole (DV 2/3), and at the end of diastole (EDV). To assess different modalities of filling, we calculated filling fractions in the first third (FF 1/3) as the ratio of volume filled in the first third diastole (DV 1/3-ESV) over total diastolic filling (EDV-ESV). Similar filling fractions (FF) were calculated at half (FF 1 /2), second third (FF 2/3), and last third (FF 3/3) of diastole. We found significant differences between normal and coronary artery disease patients as follows: FF 1/3: 37.4± 14.9 versus 23.8±11.9%, respectively (p<0.002); FF 1/2: 58.6±14.7 versus 45.3±15.1% (p<0.005); FF 2/3: 33.8±15.2 versus 39.0±10.4% (NS), and differences in the opposite direction in the FF 3/3: 28.8± 15.2 versus 37.2±11.9% (p<0.02), respectively. We conclude that LV filling is accomplished differently in patients with coronary artery disease even if they have normal systolic function.     

The impact of coronary artery disease and left ventricular ejection fraction on the prognosis of patients with peripheral artery disease

The impact of the severity of coronary artery disease (CAD) and left ventricular ejection fraction (LVEF) on the prognosis of patients with peripheral artery disease (PAD) has not been systematically studied. We retrospectively analysed 622 patients with PAD (intermittent claudication (IC): n = 446; critical limb ischaemia (CLI): n = 176). The association of SYNTAX score and LVEF with mortality was analysed using the Cox proportional hazard model. In patients with IC, a high SYNTAX score was significantly associated with mortality, whereas reduced LVEF was significantly associated with mortality in patients with CLI. The prognostic impact of CAD and LVEF appears different between patients with IC and CLI.