Prognostic influence of mitral regurgitation prior to a first myocardial infarction.

AIMS: Mitral regurgitation (MR) following an acute myocardial infarction (AMI) confers an adverse prognosis during long-term follow-up. There are no studies evaluating the influence of pre-AMI MR in the short- and long-term prognosis of such patients. Our aim was to assess the prognostic value of pre-AMI MR in the short- and long-term follow-up of patients who suffered a first AMI and to assess its influence on left ventricular haemodynamics. METHODS AND RESULTS: Sixty-eight consecutive patients with a first AMI and an echocardiographic study before AMI (<3 months) were included in the study. The pre-AMI echo was performed for various reasons. Of these 68 patients, 42 had pre-AMI MR (Group 1) and 26 showed no pre-AMI MR (Group 2). The presence of degenerative changes at the level of the mitral valve was confirmed in all cases. Patients with any other cause of MR were excluded. Clinical and echocardiographic variables for both phases (pre-AMI and post-AMI) were analysed and patients were followed up. Mean age was 75.5+/-9.5 years; there were 38 males (55.9%). There were no statistical differences in baseline clinical variables between the groups, except for the presence of pre-AMI atrial fibrillation, which was more frequent in Group 1 (21.4 vs. 0%; P = 0.01). After AMI, only end-diastolic left ventricular diameter was significantly larger in Group 1 (54.9 +/- 4.7 vs. 48.1 +/- 5.6 mm; P < 0.001). During long-term follow-up, median survival times were 912 days (interquartile range: 690 days) in Group 1 and 1423 days (interquartile range: 520 days) in Group 2 (Log-rank P = 0.02). The multivariable analysis showed that the presence of pre-AMI MR relates to a statistically significant relationship with a worse post-AMI evolution [relative risk (95% confidence interval): 3.8 (1.1-13.1); P = 0.037]. CONCLUSION: The present study shows that the presence of pre-AMI MR is an independent prognostic marker among those patients suffering a first AMI.     

Q-wave evolution of a first acute myocardial infarction without significant ST segment elevation

BACKGROUND: Some patients with acute myocardial infarction presenting without significant ST segment elevation develop a Q-wave infarction. It is unclear whether these patients can be identified from the admission electrocardiogram (ECG) and whether they differ in their in-hospital prognosis from those who retain a non-Q-wave myocardial infarction. METHODS: In 432 consecutive patients admitted to our centre with a first acute myocardial infarction without Q waves and with ST segment amplitudes < or =0.1 mV on admission, we assessed the frequency, the electrocardiographic predictors and the short-term implications of a Q-wave evolution. RESULTS: In 94 patients (22%), a Q-wave myocardial infarction evolved before hospital discharge (14 anterior, 26 inferior, six lateral, and 48 posterior). Minor anterior ST segment elevation was 36% sensitive and 95% specific in predicting anterior Q waves; minor inferior ST segment elevation, 42% and 89%, respectively, for inferior Q waves; and a maximal ST segment depression > or =0.2 mV in leads V2-V3 with upright T waves and without remote ST segment depression, 38% and 97%, respectively, for posterior R waves. Although patients with a Q-wave evolution had a greater creatinkinase MB peak than those retaining a non-Q-wave pattern (191+/-113 vs. 105+/-77 IU/l, respectively, P<0.001), they experienced a benign in-hospital course, with similar risk of severe complications after adjustment for the baseline clinical predictors than non-Q-wave patients. CONCLUSIONS: About one fifth of patients with a first acute myocardial infarction without a significant ST segment elevation develop a Q-wave infarction and the admission ECG can help identify them. This evolution, however, is not associated with a worse in-hospital outcome.     

Pulsed Doppler echocardiographic analysis of mitral regurgitation after myocardial infarction

In 72 patients with previous myocardial infarction (MI), mitral regurgitation (MR) was assessed by pulsed-wave Doppler echocardiography and compared with physical and 2-dimensional echocardiographic findings. MR was found by Doppler in 29 of 42 patients (62%) with anterior MI, 11 of 30 (37%) with inferior MI (p less than 0.01) and in none of 20 normal control subjects. MR was more frequent in patients who underwent Doppler study 3 months after MI than in those who underwent Doppler at discharge (anterior MI = 83% vs 50%, p less than 0.01; inferior MI = 47% vs 27%, p = not significant). Of 15 patients who underwent Doppler studies both times, 3 (all with anterior MI) had MR only on the second study. Of the patients with Doppler MR, 12 of 27 (44%) with a left ventricular (LV) ejection fraction (EF) greater than 30% and 1 of 13 (8%) with an EF of 30% or less (p less than 0.01) had an MR systolic murmur. Mitral prolapse or eversion and papillary muscle fibrosis were infrequent in MI patients, whether or not Doppler MR was present. The degree of Doppler MR correlated with EF (r = -0.61), LV systolic volume (r = 0.47), and systolic and diastolic mitral anulus circumference (r = 0.52 and 0.51, respectively). Doppler MR was present in 24 of 28 patients (86%) with an EF of 40% or less and in 16 of 44 (36%) with EF more than 40% (p less than 0.001).(ABSTRACT TRUNCATED AT 250 WORDS)     

Improved prognosis after coronary thrombolysis with urokinase in acute myocardial infarction

The effectiveness of coronary thrombolysis with urokinase (UK) on short- and long-term outcome after acute myocardial infarction was studied by comparison of 120 patients treated with UK and 124 with conventional therapy followed up for a period of 20 months. UK was administered to patients within 6 hours of the onset of chest pain, by the intracoronary route (20,000 U/min, at a mean dose of 698,000 U) in 46 patients, intravenously (960,000 to 1,920,000 U in 15 or 30 min, at a mean dose of 1,293,000 U) in 56 patients and by the combined route (at a mean dose of 2,333,000 U) in 18 patients. Complete occlusion or 99% stenosis with severe delay of the contrast medium was found in 72.5% and recanalization by UK was achieved in 68.0%. Cumulative mortality rate was significantly reduced in the UK group (9.2% vs. 29.0%). Cardiac death from recurrent MI was also significantly reduced (2.5% vs. 10.5%). The reduction in mortality rate was demonstrated even in older patients as well as in those cases graded as severe according to the Killip and Forrester classifications. Thus, it is concluded that coronary thrombolysis with UK therapy improves the prognosis of acute myocardial infarction.     

New-onset angina preceding acute myocardial infarction is associated with improved contractile recovery after thrombolysis

Background Ischaemic preconditioning reduces myocardial infarct size inanimal models. Clinical data suggest that episodes of anginaimmediately before acute myocardial infarction may be associatedwith smaller infarct size in man. However, it is unclear whetherischaemic episodes preceding acute myocardial infarction alsoaffect contractile recovery in patients. Objective In this study we investigated the recovery of regional myocardialfunction after thrombolysis in two groups of patients at theirfirst Q-wave acute myocardial infarction; in one group (n=42)myocardial infarction occurred unheralded, whereas patientsof the second group (n=48) had experienced new-onset anginain the 48h that preceded infarction. Echocardiographic analysisof myocardial regional function in the infarct area was doneat 2, 24 and 72h after thrombolysis, and at 1 week, and 1 and3 months follow-up. Results Peak level of MB-creatine kinase was significantly lower inpatients with new-onset angina (96±47 as compared with221±108IU.l^–1, P<0·01), as was the areaunder the MB-creatine kinase curve (1321±876 as comparedto 3879±1555U.l^–1/36h, P<0·01). Hypokineticsegments were fewer in patients with pre-infarction angina.Similarly, wall motion score improved significantly earlierin patients who had new-onset angina before acute myocardialinfarction. Thus, contractile recovery was more rapid in patientswith previous angina than in those in whom infarction occurredunheralded. Complications during the in-hospital outcome andother variables considered during the 4-week follow-up weresimilar between groups. Conclusions Patients who experienced new-onset angina before acute myocardialinfarction showed better recovery of regional function afterthrombolysis. Our study supports the hypothesis that brief periodsof ischaemia immediately before myocardial infarction may preconditionthe human heart, thus improving contractile recovery.     

急性心肌梗死早期伴发二尖瓣关闭不全对患者预后影响

目的:探讨急性心肌梗死(AMI)患者伴发二尖瓣关闭不全(MR)的临床意义及预后。方法:将2年来我院收治的AMI患者145例分为MR组与no-MR组;根据梗死部位分为前壁AMI组与下壁AMI组,前、下壁各组又根据是否伴发MR分为:前壁MR组与前壁no-MR,下壁MR组与下壁no-MR组4个亚组。观察各组的临床情况与心血管事件。结果:MR组63例,占43.4%,与no-MR组相比,其年龄、左心室射血分数、终点心血管事件及随访期间心血管事件均差异具有统计学意义(P<0.05)。亚组间相比,前壁AMI-MR组与下壁AMI-MR组与相应的no-MR组比较终点心血管事件差异具有统计学意义,且该2组间随访期间临床心血管事件差异具有统计学意义(P<0.05);下壁AMI-MR组与no-MR组2组间的终点心血管事件差异具有统计学意义(P<0.05)。结论:AMI患者伴发MR提示预后不良,AMI患者伴有MR与梗死部位有关,且其部位与预后密切相关。     

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.     

Ischemic mitral regurgitation and risk of heart failure after myocardial infarction

BACKGROUND: The development of ischemic mitral regurgitation (MR) after myocardial infarction may impose hemodynamic load during a period of active left ventricular remodeling and promote heart failure (HF). However, few data are available on the relationship between ischemic MR and the long-term risk for HF. METHODS: We prospectively studied 1190 patients admitted for acute myocardial infarction. Mitral regurgitation was assessed by echocardiography and was considered mild, moderate, and severe when the regurgitant jet area occupied less than 20%, 20% to 40%, and greater than 40% of the left atrial area, respectively. The median duration of follow-up was 24 months (range, 6-48 months). RESULTS: Mild and moderate or severe ischemic MR was present in 39.7% and 6.3% of patients, respectively. After adjusting for ejection fraction and clinical variables (age, sex, Killip class, previous infarction, hypertension, diabetes mellitus, anterior infarction, ST-elevation infarction, and coronary revascularization), compared with patients without MR, the hazard ratios for HF were 2.8 (95% confidence interval [CI], 1.8-4.2; P<.001) and 3.6 (95% CI, 2.0-6.4; P<.001) in patients with mild and moderate or severe ischemic MR, respectively. The adjusted hazard ratios for death were 1.2 (95% CI, 0.8-1.8; P = .43) and 2.0 (95% CI, 1.2-3.4; P = .02) in patients with mild and moderate or severe MR, respectively. CONCLUSIONS: There is a graded independent association between the severity of ischemic MR and the development of HF after myocardial infarction. Even mild ischemic MR is associated with an increase in the risk of HF.     

急性心肌梗塞后二尖瓣返流的临床意义

用彩色多普勒超声对91例急性首次心梗3天内患者的二尖瓣返流进行了测定,并对患者进行了平均22.1月的随访.发现伴二尖瓣返流患者占34%,这些患者女性多,年龄大,梗塞面积大,非Q波梗塞多,Ptfv_1小和房性心律失常多,而且使用强心剂及利尿剂患者多,住院期心功能差,心脏事件多和观察期死亡率高,但二尖瓣返流不是预测死亡的独立因素.表明心梗急性期彩色多普勒测定的二尖瓣返流可能只是反映数种危险因素的一个综合性的信息,而非独立于其它因素之外的预后指标.     

二尖瓣反流对急性心肌梗死预后的意义

目的　探讨二尖瓣反流 (MR)对急性心肌梗死 (AMI)患者预后的意义。方法　对 142例 AMI患者住院早期(7天内 )进行超声心动图检查 ,以彩色多普勒定量测定其 MR。并对 MR组及无 MR组的临床资料、超声心动图指标及预后进行对比分析。结果　 142例 AMI患者无 MR90例 (6 3.38%) ,轻度 MR43例 (30 .2 8%) ,中、重度 MR9例 (6 .34 %)。 MR组较无 MR组患者年龄更大、既往心肌梗死患病率及高血压患病率更高 (P均 <0 .0 5 )。 MR组脉冲多普勒 E峰、E/A显著高于无 MR组 (P均 <0 .0 5 )。 MR组 30天及 1年死亡率均显著高于无 MR组 (P<0 .0 5和 P<0 .0 1)。结论　超声心动图证实的 MR对 AMI患者的预后具有预测价值。     

Significance of Doppler-detected mitral regurgitation in acute myocardial infarction

To define the incidence of mitral regurgitation (MR) and elucidate its potential contribution to the development of severe congestive heart failure after acute myocardial infarction (AMI), Doppler echocardiograms were obtained within 48 hours of onset of AMI in 59 patients. The presence of MR was determined from the apical 4-chamber and parasternal long-axis views with pulsed Doppler. MR was detected in 23 of the 59 patients (39%) and was similarly frequent in patients with anterior (11 of 24 or 46%) and inferior AMI (12 of 34 or 35%). Patients with MR were older (71 +/- 3 vs 62 +/- 2 years, p less than 0.005), had a higher incidence of prior AMI (8 of 23 vs 4 of 36, p less than 0.05) and larger end-diastolic volume indexes by radionuclide ventriculography (112 +/- 9 vs 72 +/- 4, p less than 0.005). A systolic murmur was heard in only 10 of 23 patients with MR detected by Doppler. Mortality determined 8 to 14 months after the index AMI was 48% (11 of 23) in patients with MR but only 11% (4 of 30) in those without it (p less than 0.01). Thus, this study determined that clinically silent MR frequently complicates AMI and its presence is associated with and is a potential determinant of severe congestive heart failure and mortality.     

Contribution of ischemic mitral regurgitation to congestive heart failure after myocardial infarction

OBJECTIVES: The purpose of this study was to define the contribution of ischemic mitral regurgitation (IMR) to the occurrence of congestive heart failure (CHF) after myocardial infarction (MI). BACKGROUND: After MI, CHF is a frequent and serious complication, but its determinants and, particularly, the role of IMR are poorly defined. METHODS: We analyzed 173 asymptomatic patients with previous Q-wave MI (>16 days) with echocardiographic quantitation of IMR (measuring effective regurgitant orifice [ERO] and regurgitant volume). The 102 patients with IMR were matched to 71 patients without IMR for age (71 +/- 11 years vs. 68 +/- 9 years; p = 0.11), gender (76% vs. 82% males; p = 0.41), and left ventricular ejection fraction (EF) (37 +/- 14% vs. 36 +/- 11%; p = 0.92). RESULTS: Five-year rates of CHF and of CHF or cardiac death (CD) were 36 +/- 5% and 52 +/- 5%, respectively. Independent determinants of CHF were EF, sodium plasma level, and presence and degree of IMR (p < 0.0001). Five-year CHF rates were 18 +/- 5% without mitral regurgitation (MR), 53 +/- 7% with IMR, 46 +/- 9% with ERO 1 to 19 mm(2) and 68 +/- 12% with ERO > or =20 mm(2) (all p < 0.0001). The adjusted relative risk of CHF was 3.65 (95% confidence interval [CI] 1.86 to 7.75) for IMR presence and 4.42 (95% CI 1.9 to 10.5) for ERO > or =20 mm(2). The adjusted relative risk of CHF/CD was 2.97 (95% CI 1.77 to 5.16) for IMR presence and 4.4 (95% CI 2.4 to 8.2) for ERO > or =20 mm(2). CONCLUSIONS: After MI, incidence of CHF and of CHF/CD are high even in patients with no or minimal symptoms at baseline and are higher in patients with IMR. Congestive heart failure is independently determined by larger ERO of IMR. These data suggest that detecting and quantifying IMR is essential for risk stratification after MI. Value of IMR treatment in improving post-MI outcome should be investigated.     

Clinical significance of myocardial contraction fraction in significant primary mitral regurgitation

BackgroundThe optimal timing for mitral valve (MV) surgery in asymptomatic patients with primary mitral regurgitation (MR) remains a matter of debate. Myocardial contraction fraction (MCF) − the ratio of the left ventricular (LV) stroke volume to that of the myocardial volume − is a volumetric measure of LV myocardial shortening independent of size or geometry.AimTo assess the relationship between MCF and outcome in patients with significant chronic primary MR due to prolapse managed in contemporary practice.MethodsClinical, Doppler-echocardiographic and outcome data prospectively collected in 174 patients (mean age 62 years, 27% women) with significant primary MR and no or mild symptoms were analysed. The impact of MCF< or ≥30% on cardiac events (cardiovascular death, acute heart failure or MV surgery) was studied.ResultsDuring an estimated median follow-up of 49 (22–77) months, cardiac events occurred in 115 (66%) patients. The 4-year estimates of survival free from cardiac events were 21 ± 5% for patients with MCF <30% and 40 ± 6% for those with ≥30% (P < 0.001). MCF <30% was associated with a considerable increased risk of cardiac events after adjustment for established clinical risk factors, MR severity and current recommended class I triggers for MV surgery (adjusted hazard ratio: 2.33, 95% confidence interval: 1.51−3.58; P < 0.001). Moreover, MCF < 30% improved the predictive performance of models, with better global fit, reclassification and discrimination.ConclusionsMCF < 30% is strongly associated with occurrence of cardiac events in patients with significant primary MR due to prolapse. Further studies are needed to assess the direct impact of MCF on patient management and outcomes.     

急性心肌梗死溶栓治疗后ST段再抬高的临床分析

目的 :观察急性心肌梗死 (AMI)静脉溶栓治疗后ST段再抬高的临床特点。方法 :回顾性分析符合静脉溶栓标准的AMI患者 1 0 7例 ,根据溶栓后有无ST段再抬高而分为ST段抬高组 (A组 )和ST段未抬高组 (B组 ) ,比较两组间发病年龄、伴发疾病、梗死相关血管、再通率、梗死后开始溶栓时间、再灌注心律失常、心功能变化 (Kil lip分级)。结果 :A组伴发糖尿病、高血压、高脂血症、梗死血管多支病变、心功能不全、再灌注心律失常发生率均高于B组 ,而冠状动脉再通率明显低于B组。结论 :溶栓治疗后ST段再抬高与患者并发糖尿病、高血压、高脂血症密切相关 ,梗死相关冠状动脉存在多支病变。该类患者再通率低 ,心肌受损重 ,易并发心功能不全 ,再灌注心律失常发生率高     

急性心肌梗死后二尖瓣反流与左心室大小和功能的相关分析

目的探讨急性心肌梗死（AMI）二尖瓣反流（MR）患者左心室功能与远期预后的关系。方法入选143例AMI患者,平均入院5d内行超声心动图检查,检测MR情况、左室舒张期末内径（LVEDD）、左室收缩期末内径（LVESD）、左房内径（LAD）、左室射血分数（LVEF）、E／A比值。根据LVEF大小将患者分为2组（≥50％组和〈50％组）;随访的中位数时间为432d,观察两组心力衰竭、再发心肌梗死、再发心绞痛、心因性死亡等心血管事件的发生率与LVEF的相关性。结果AMI患者MR发病率73．4％。MR的发生及程度与Killip分级、LVEF值、LVEDD、LVESD、LAD、E／A比值等相关。左心室大小和功能与AMI后心血管事件显著相关。生存分析显示,AMI后MR患者LVEF〈50％是远期死亡的独立危险因素（P〈0．01）。结论AMI后基线水平MR的严重程度与左室功能和大小显著相关,左室功能恶化是远期死亡的显著预测因子。