Long-term prognostic significance of left atrial volume in acute myocardial infarction

OBJECTIVES: The aim of this study was to evaluate the significance of increased left atrial (LA) volume determined within the first 48 h of admission as a long-term predictor of outcome in patients with acute myocardial infarction (MI). BACKGROUND: The LA volume reflects left ventricular (LV) diastolic properties. Whereas other LV Doppler diastolic characteristics are influenced by acute changes in LV function, LA volume is stable and reflects diastolic properties before MI. METHODS: Clinical and echocardiographic parameters were prospectively collected in 395 consecutive patients with acute MI. Patients with LA volume index (LAVI) >32 ml/m(2) (normal + 2 standard deviations) were compared with those with LAVI <==32 ml/m(2). Independent clinical and echocardiographic prognostic risk factors for five years' mortality were determined by the Cox proportional hazard model. RESULTS: Left atrial volume index >32 ml/m(2) was found in 63 patients (19%) who had a higher incidence of congestive heart failure on admission (24% vs. 12%, p < 0.01), a higher incidence of mitral regurgitation, increased LV dimensions, and reduced LV ejection fraction when compared with patients with LAVI <==32 ml/m(2). Their five-year mortality rate was 34.5% versus 14.2% (p < 0.001). Significant independent risk predictors of five years' mortality were age (10 years) (odds ratio [OR] 1.45; 95% confidence interval [CI]1.14 to 1.86), Killip class >/=2 on admission (OR 2.30; 95% CI 1.29 to 4.09), LAVI >32 ml/m(2) (OR 2.22; 95% CI 1.25 to 3.96), diabetes (OR 1.94; 95% CI 1.15 to 3.28), and LV restrictive filling pattern (OR 1.89; 95% CI 1.09 to 3.31). CONCLUSIONS: In patients with acute MI, increased LA volume, determined within the first 48 h of admission, is an independent predictor of five-year mortality with incremental prognostic information to clinical and echocardiographic data.     

Differential prognostic importance of QRS duration in heart failure and acute myocardial infarction associated with left ventricular dysfunction

BACKGROUND/AIMS: Studies of the prognostic importance of QRS duration in patients with heart failure (HF) have shown conflicting results and few studies have estimated the importance after myocardial infarction (MI). METHODS: The Danish Investigations and Arrhythmia ON Dofetilide (DIAMOND) study randomised 3028 patients to dofetilide (class III antiarrhythmic) or placebo. The study consisted of two almost identical trials conducted simultaneously. One trial included 1518 patients with chronic HF and the other trial 1510 patients with a recent MI. All patients had left ventricular dysfunction. Dofetilide did not influence mortality in either trial. QRS duration was systematically measured at randomisation and was available in 2972 patients. RESULTS: Over a 10 year observation period 1037 (70%) patients in the MI study and 1324 (87%) in the HF study died. In the MI study, risk of death increased 6% for each 10 ms increase in QRS duration (HR=1.06/10 ms increase in QRS (CI=1.04-1.09), p<0.0001) whereas QRS duration had no influence in the HF study after multivariable adjustment. The difference between HF and MI was significant (p<0.0004 for interaction). CONCLUSION: QRS duration predicts death in patients with left ventricular dysfunction who have suffered MI. In patients with HF QRS duration is not predictive of mortality.     

Remodeling of myocardial interstitium in left ventricular hypertrophy and myocardial infarction

Structural and biochemical modifications of the myocardium (remodeling) occur during the development of left ventricular hypertrophy and acute myocardial infarction. An important part of this process of myocardial remodeling occurs in the interstitial compartment. The myocardial interstitium is composed mainly of fibrillar collagen. These changes are associated to modifications in ventricular function that could be deleterious and have clinical manifestations. Some salutory effects of the treatment of both conditions are related to modifications of the process of myocardial interstitial remodeling.     

Prognostic significance of ischemic mitral regurgitation after non-Q-wave acute myocardial infarction

BACKGROUND AND AIM OF THE STUDY: The development of mitral regurgitation (MR) soon after acute myocardial infarction (AMI) is a recognized and frequent complication. Its negative impact on survival has been observed after Q-wave AMI, even when of a mild degree, and independently of left ventricular systolic function. Few data exist regarding MR after non-Q-wave AMI (nQ AMI), however. Hence, the study aim was to investigate the incidence, clinical predictors and prognostic implications of MR in the setting of nQ AMI. METHODS AND RESULTS: A total of 99 consecutive patients (37 men, 62 women; mean age 72 +/- 13 years) who suffered a nQ AMI was studied. All patients underwent echocardiography during the first week after the nQ AMI. MR was detected in 34 patients (17 men, 17 women; mean age 76 +/- 10 years). Events during follow up were coded as death, AMI, unstable angina, or heart failure. The in-hospital outcome was not significantly different between patients with and without MR. The mean follow up period was 663 +/- 574 days. In the univariate analysis, freedom from hospital survival was significantly greater in patients without MR. However, multivariate analysis showed that MR was not an independent predictor of cardiovascular hospitalization or death. CONCLUSION: The incidence of MR is high among patients with nQ AMI but, unlike results found with Q-wave AMI, its presence does not add any prognostic significance to other known negative factors in the setting of nQ AMI.     

急性心肌梗死后左室重构临床研究

目的　探讨溶栓治疗对急性心肌梗死后左室结构和功能的影响。方法　对 36例首发急性心肌梗死患者于梗死后 4周和 12周进行超声心动图观察。分别测定左室舒张末期容积指数 (LVEDVI)、左室收缩末期容积指数 (LVESVI)、射血分数 (EF) ,作为反映左室结构和功能变化的指标。结果　急性心肌梗死后LVEDVI、LVESVI均明显增高 (分别为P <0 0 1,P <0 0 5 )。 4周和 12周检查发现 ,溶栓组LVEDVI、LVESVI无明显差异 (分别P>0 0 5 ,P >0 0 5 ) ,EF值明显增大 (P <0 0 5 ) ;未溶栓组LVEDVI、LVESVI明显增大 (分别为P <0 0 5 ,P <0 0 5 ) ,EF值无明显变化 (P >0 0 5 ) ;对 4周和 12周的检查结果作组间比较发现 ,溶栓组LVEDVI、LVESVI均小于未溶栓组 (P <0 0 5 ) ,EF值溶栓组高于未溶栓组 (P <0 0 5 )。结论　溶栓治疗能有效地抑制急性心肌梗死后左室重构 ,改善心功能。     

Clinical and prognostic significance of silent myocardial ischemia in survivors after acute myocardial infarction

To clarify the clinical and prognostic significance of silent myocardial ischemia (SMI) after acute myocardial infarction (MI), the clinical characteristics and long-term prognosis after discharge in 525 medically treated survivors after acute MI were investigated. According to the presence of post-infarction angina and results of all exercise tests during hospitalization, 309 patients without ischemic episodes were classified into control group, 59 patients with SMI into SMI group and 157 patients with post-infarction angina into AP group. Previous MI (29%, 24%, 11%, respectively), non-Q wave MI (34%, 34%, 15%) and multivessel disease (69%, 61%, 33%) were more frequent in the SMI and AP groups than in the control group. These indicated clinical characteristics in patients with SMI were similar to those in patients with angina pectoris. The incidence of angina prior to MI onset in patients with SMI was lower than in patients with post-infarction angina. This may suggest that there is some common mechanism keeping them silent in the pre- and post-MI period. During the mean follow-up period of 5.5 years, 93 patients died and 78 had a recurrent MI. Cumulative total and cardiac mortality, and incidence of recurrent MI by actuarial method were higher in the SMI as well as AP group than in the control group. There was no statistically significant difference in prognosis between SMI and AP group. We conclude total ischemic burden, not only symptomatic but SMI, should be treated using currently available therapeutic modalities for further improvement of long-term prognosis in survivors after acute MI.     

A prognostic comparison of asymptomatic left ventricular hypertrophy and unrecognized myocardial infarction: the Framingham Study

In 30 years of follow-up in the Framingham study, routine biennial ECG examinations revealed 315 subjects with ECG-LVH and 164 with unrecognized ECG-MI without previous cardiac explanation. Among subjects initially free of clinically evident coronary heart disease and both ECG abnormalities, the incidence of ECG-LVH was about double that of ECG-MI. Both events exhibited a male predominance and hypertensive subjects were more vulnerable to each. In subjects with asymptomatic ECG-LVH and ECG-MI, the 10-year, age-adjusted incidence of clinical coronary heart disease was greater than the rate experienced by the general Framingham sample. Rates for ECG-LVH were almost as large as those for ECG-MI. Cardiac failure and stroke also occurred more frequently among subjects with either ECG abnormality, and rates for ECG-LVH exceeded those for ECG-MI. Death from coronary heart disease, and sudden death in particular, was also increased two- to fourfold with similar risks for ECG-LVH and ECG-MI. ECG-LVH carried a significantly greater risk than ECG-MI for cardiovascular deaths in women. These findings suggest that ECG-LVH and ECG-MI are similar subclinical events with respect to predisposing characteristics and prognosis for subsequent overt cardiovascular disease including clinical manifestations of coronary heart disease.     

Clinical predictors of early left ventricular thrombus formation in acute myocardial infarction

OBJECTIVE: Clinical epidemiological and echocardiographic risk factors relating to the development of a left ventricular thrombus were studied retrospectively in patients with acute myocardial infarction. METHODS AND RESULTS: The data on 1833 consecutive patients treated for acute myocardial infarction during a 10-year period were processed retrospectively. Transthoracic echocardiography was performed on each patient 65.0 +/- 5.5 hours after hospital admission. A left ventricular thrombus was detected in 145 patients (7.9%). The patients with acute myocardial infarction and a left ventricular thrombus had significantly lower frequencies of 1) myocardial infarction in their family history (3% versus 11%, respectively), 2) hospital admission within 24 hours from the onset of chest pain (17% versus 50%, respectively), 3) thrombolytic therapy (8% versus 23%, respectively) and 4) current smoking (24% and 35%, respectively) than those without a left ventricular thrombus. In contrast, anterior infarction (81% versus 38%, respectively), left ventricular dilatation (30% versus 19%, respectively), dyskinesis of the left ventricular wall (23% versus 10%, respectively), an aneurysm (22% versus 7%, respectively) and a reduced systolic left ventricular function (ejection fraction < 40%) (28% versus 17%, respectively) were more frequent in the presence of a left ventricular thrombus after myocardial infarction. Multivariate analysis of the results revealed that the presence of anterior myocardial infarction and an aneurysm is associated with significantly increased hazard ratios. On the other hand, early hospitalization and a positive family history of infarction significantly lowered the hazard ratio. The frequency of a left ventricular thrombus was significantly higher in spring and winter. CONCLUSIONS: The results presented in this paper confirm the significant hazard of certain parameters [location of infarction (anterior) and aneurysm] as concerns left ventricular thrombus formation among patients with acute myocardial infarction. Early hospitalization was found to lower the risk of thrombus formation.These echocardiographic and clinical parameters may be useful in the establishment of the individual risk of intracavital thrombus formation and may be of help in everyday medical practice.     

Longitudinal changes and prognostic implications of left ventricular diastolic function in first acute myocardial infarction

BACKGROUND: Left ventricular (LV) diastolic dysfunction contributes to signs and symptoms of clinical heart failure and may be related to prognosis in heart diseases. LV diastolic dysfunction is reported to be present in acute myocardial infarction (MI); however, little is known about the time course of changes in LV diastolic function and its relation to prognosis after acute MI. METHODS AND RESULTS: Two-dimensional and Doppler echocardiographic examinations were performed in 58 consecutive patients with first acute MI. The patients were studied serially within 1 hour and at days 5, 90, and 360 after arrival to the coronary care unit. LV diastolic function was assessed by Doppler measurements of transmitral and pulmonary venous flow. On the basis of mitral inflow, patients with MI were stratified at baseline to 3 LV diastolic filling patterns: normal, impaired relaxation, or pseudonormal/restrictive. Patients with MI were observed for development of congestive heart failure (Killip class >I) during hospitalization and for death during 1-year follow-up, and these complications were related to LV diastolic function. LV diastolic dysfunction was present in the very early phase of acute MI, with signs of impaired relaxation or restrictive LV filling dynamics in 38% and 24% of the patients, respectively, whereas 38% had normal LV filling characteristics. Impaired relaxation of the LV was most pronounced and found in 60% after 1-year follow-up. In-hospital congestive heart failure (Killip class >I) was found in 50% of the patients with initial impaired LV relaxation and in 71% of the patients with initially pseudonormal or restrictive LV filling dynamics, whereas patients with normal LV filling were free of heart failure. Patients with initial impaired relaxation and restrictive LV filling dynamics demonstrated a significant LV dilation during 1-year follow-up. Patients with initial pseudonormal/restrictive LV filling pattern were more frequently readmitted to the hospital for heart failure and had significant higher New York Heart Association class score compared with patients with normal or impaired relaxation during follow-up. Cardiac death was (n = 6) only observed in patients with pseudonormal or restrictive LV filling pattern. In a multivariate stepwise regression analysis, mitral E deceleration time 相似文献   

急性心肌梗死合并室间隔穿孔患者的临床特点及预后因素分析

目的总结分析急性心肌梗死(AMI)合并室间隔穿孔(VSR)患者的临床特点。方法纳入首都医科大学附属北京朝阳医院1999年1月至2018年10月共收治AMI 16038例,其中合并VSR患者44例,对这44例AMI合并VSR患者的临床资料进行回顾性分析。结果44例AMI合并VSR患者中男性24例(54.5%),女性20例(45.5%),平均年龄(71.0±6.5)岁;前壁心肌梗死患者(包括累及前壁的心肌梗死)35例(79.5%),非前壁心肌梗死9例(20.5%)。手术治疗9例,其中7例为室间隔缺损介入封堵术,2例外科手术(1例为室间隔修补术+冠状动脉旁路移植术+室壁瘤切除术,1例为室间隔修补术+冠状动脉旁路移植术+瓣膜修补术)。术后心功能改善情况均较显著,除2例封堵术患者院内死亡外,其余手术患者生存期均大于1年。结论VSR是AMI少见但严重的并发症,手术治疗的近期预后明显优于非手术治疗,介入封堵治疗在改善症状及预后等方面发挥出日益重要的作用。     

Clinical significance of ventricular dyskinesis in acute myocardial infarction assessed by apexcardiography

Apexcardiograms [ACG] recorded in 64 patients with anterior acute myocardial infarction disclosed in 36 cases [56.2%] paradoxal systolic precordial pulsation considered as an expression of ventricular dyskinesis [VD]. The functional significance of VD was assessed by the left ventricle systolic time intervals. There was a significant shortening of the left ventricular ejection time (LVET) and a significant increase in the pre-ejection period (PEP) and of PEP/LVET ratio in patients with VD. The heart/chest ratio was greater in patients with VD but the difference was not statistically significant. The condition of the heart after the acute phase of myocardial infarction was much better in patients without VD or with transient VD in than in those with permanent VD. 91.3% of the patients with permanent VD presented heart failure and belonged to the functional class III-IV. These findings indicate that patients presenting ACG-assessed VD have frequently an altered cardiac performance and a worse long-term prognosis.     

Clinical setting and prognostic significance of atrial fibrillation complicating acute myocardial infarction.

Clinical setting, presence and degree of heart failure (HF) of 80 consecutive patients who developed atrial fibrillation (AF) following acute myocardial infarction were compared to that of 620 patients with acute myocardial infarction and sinus rhythm admitted during the same period. 33 of 163 (20%) with initially mild HF developed AF compared to 5 of 74 (7%) with initially severe HF, and 42 of 463 (9%) without HF (P less than 0.01). Patients with mild HF who developed AF had a higher incidence of deterioration of clinical condition (39 vs 14%, P less than 0.005) and a higher mortality rate (52 vs 22%, P less than 0.001) than patients with mild HF and sinus rhythm. The presence of AF influenced neither the development of HF and mortality rate in patients without HF nor the degree of HF and mortality in patients with initially severe HF. Pericarditis was present in 12 of 42 (28%) with AF occurring in the absence of HF, compared to 3 of 38 (8%) with AF and initially mild HF and to 56 of 620 (9%) with sinus rhythm (P less than 0.05). Conclusions: (1) in the absence of HF, AF may be the consequence of pericarditis; (2) in patients with mild HF, AF may be consequence of HF; (3) the contribution of AF to the subsequent clinical course is only of prognostic significance in patients with mild HF.     

急性心肌梗死早期左室重构与发病时间

目的 采用心肌静息门控单光子发射计算机体层摄影术（ＧＳＰＥＣＴ）研究了急性心肌梗列死（ＡＭＩ）早期左室的重构特点。方法 ＡＭＩ患者３７例,根据发病时间分作四个亚组,第一亚组（１６例）,第二亚组（７例）,第三亚组（１１例）和第四亚组（３例）,患者发病时间分别为≤３小时,〉３小时￣≤６小时,〉６小时￣≤１２小时和〉１２小时。患者入院后即注射显影剂＾９９ｍ锝甲氧基异丁基异腈,２小时后采用双探头ＧＳＰＥＣ