Prognostic implications of left ventricular diastolic dysfunction with preserved systolic function following acute myocardial infarction

The contribution of diastolic dysfunction in patients with preserved left ventricular (LV) systolic function to impaired functional status and cardiac mortality in myocardial infarction (MI) is unknown. In the present study, assessment of LV diastolic function was performed by Doppler analysis of the mitral and pulmonary venous flow, and the propagation velocity of early mitral flow by color M-mode Doppler echocardiography in 183 consecutive patients at day 5-7 following their first acute MI. Patients were classified into four groups: group A: preserved LV systolic and diastolic function (n = 73); group B: LV systolic dysfunction with preserved diastolic function (n = 10); group C: LV diastolic dysfunction with preserved systolic function (n = 60); group D: combined LV systolic and diastolic dysfunction (n = 40). The cardiac mortality rate at 1 year was significantly higher in groups C (13%) and D (38%) compared to A (2%) (p < 0.01). Multivariate regression analysis identified LV diastolic dysfunction (p = 0.001), Killip class >or=II (p = 0.006), and age (0.008) as predictors of cardiac death or readmission due to heart failure. The presence of LV diastolic dysfunction with preserved systolic dysfunction is associated with increased morbidity and mortality following acute MI.     

Prognostic importance of digitalis after acute myocardial infarction

Because previous reports have suggested that digitalis administration may lead to increased mortality after hospital discharge for acute myocardial infarction, the independent importance of digitalis therapy in long-term prognosis after acute myocardial infarction was investigated by analyzing 1,599 patients after definite myocardial infarction. After hospital discharge, mortality rate for the entire group at 4 months was 7.7% and after 1 year 14.2%. At discharge, 36.6% of the patients were taking digitalis. Compared with those not taking digitalis, those taking digitalis had more historical risk factors and a higher incidence of important clinical prognostic variables during the hospitalization. Their cardiac mortality rate after 4 months and 1 year (12.5 and 22.4%, respectively) was significantly higher than that of patients not taking digitalis (5.0 and 9.6%, respectively). Mortality was higher for patients taking digitalis whether or not they had congestive heart failure during hospitalization. However, in a multivariate Cox analysis for 1 year outcome, neither digitalis nor any other medication variable displaced the important clinical variables of age, congestive heart failure during the hospitalization, previous myocardial infarction, maximal heart rate during the hospitalization and previous angina. Quinidine and digitalis at discharge were selected sixth and seventh (not significant) by the analysis. It is concluded that digitalis therapy at discharge after myocardial infarction was not an independent predictor of late mortality in these patients.     

Effects of captopril on left ventricular systolic and diastolic function after acute myocardial infarction.

The left ventricle progressively dilates in some patients after acute myocardial infarction (AMI). Both systolic and diastolic left ventricular (LV) dysfunction can be of significance in the development of heart failure. Captopril has been shown to prevent dilatation, but the effect on LV diastolic function is unknown. In a placebo-controlled double-blind parallel study, 58 AMI patients with heart failure or low ejection fraction, or both, were consecutively randomized at day 7 to either placebo or captopril (25 mg twice daily). No differences were present between the groups at baseline. Fifty-three patients completed the 6-month study period. Both LV diastolic and systolic volume indexes increased significantly in the placebo group (17 and 14%, respectively); in the captopril group there was no change in LV diastolic volume index, but a 13% reduction in LV systolic volume index. Ejection fraction increased significantly in the captopril group. The peak flow velocities of the early and atrial filling phases were measured, and the ratio between the velocities was calculated. A significant reduction was observed during the study period in early peak flow velocity (65 to 52 cm/s) and in the ratio between early and atrial peak flow velocity (1.3 to 0.8) in the placebo group (p less than 0.05), but no significant changes occurred in the captopril group. No correlation was found between dilatation of the left ventricle and reduction in early peak flow velocity or the ratio between early and atrial peak flow velocity. In conclusion, captopril prevented LV dilatation, improved ejection fraction and prevented LV diastolic dysfunction in AMI patients with early signs of LV systolic dysfunction.     

Prognostic value of global myocardial performance indices in acute myocardial infarction: comparison to measures of systolic and diastolic left ventricular function

STUDY OBJECTIVES: Assessment of global myocardial performance by a single index (ie, the myocardial performance index [MPI]) has been suggested as an appealing alternative to the individual assessment of systolic and diastolic left ventricular (LV) function We sought to test the prognostic value of MPI in comparison to clinical characteristics and echocardiographic parameters of LV filling and ejection in acute myocardial infarction (AMI). PATIENTS: Four hundred seventeen consecutive patients with AMI were examined within 24 h of hospital admission. INTERVENTIONS: Doppler echocardiographic measures of systolic, diastolic, and global myocardial performance were assessed within 24 h of hospital admission. In addition to MPI (ie, the sum of the isovolumic time intervals divided by ejection time), we determined the isovolumic/heterovolumic time ratio, which expresses the time "wasted" by the myocardium to generate and decrease LV pressure without moving blood. RESULTS: The end points of the study at 30 days were death (4.7%), congestive heart failure (23%), and recurrent infarction (4.8%), and occurred in 109 patients, who were compared as group B to 314 patients without an event (group A). Multivariate analysis identified only age (odds ratio [OR], 1.04; 95% confidence interval [CI], 1.02 to 1.07), LV ejection fraction (LVEF) < or = 40% (OR, 3.82; 95% CI, 2.15 to 6.87), and E-wave deceleration time (EDT) of < or = 130 ms (OR, 2.29; 95% CI, 1.0 to 5.21) as independent predictors of adverse events. CONCLUSION: LVEF and EDT are powerful and independent echocardiographic predictors of poor outcome following AMI, and are superior to indexes of global LV performance. Both parameters should be taken into consideration when deciding about the management of these patients.     

急性心肌梗塞后左室舒张功能影响因素的探讨

为探讨急性心肌梗塞（ＡＭＩ）左室舒张功能的变化及影响因素，我们用脉冲多普勒超声心动图测量了７２例ＡＭＩ患者的左室舒张功能，并用多元逐步回归对其影响因素进行了分析。结果表明，７２例病人中Ｅ／Ａ＜１者４１例，占５６．９％。ＡＭＩ后左室舒张功能除受年龄影响外，梗塞面积的大小直接影响左室舒张功能，但与梗塞部位无关，梗塞前心绞痛可减轻梗塞后左室舒张功能的损害，是通过减小梗塞面积而实现的。溶栓治疗可以改善心肌梗塞后的左室舒张功能。     

Specific tissue Doppler predictors of preserved systolic and diastolic left ventricular function after an acute anterior myocardial infarction

The degree of left ventricular (LV) dysfunction determines the outcome of patients suffering an acute anterior myocardial infarction (AAMI). Many recent studies have utilized tissue Doppler echocardiography (TDE) parameters in the assessment of LV function. We sought to investigate whether some variables easily obtained from TDE profiles of mitral annulus corners would predict a relatively preserved LV global function traditionally assessed with ejection fraction (EF) and deceleration time (DT), within the acute phase of AAMI. Included were 50 consecutive patients with a first AAMI. Standard echocardiography and TDE of mitral annulus were performed within 36 hours of admission. Pulsed wave sample volumes were set at the septal, lateral, anterior, and inferior corners of the mitral annulus. Preserved LV function was defined as an EF > 40% together with a DT > or = 140 ms and < 220 ms. An inferior annular systolic velocity of > 7.5 cm/s predicts preserved global left ventricular function with a sensitivity of 81% and specificity of 71%. An anterior mitral annular early diastolic velocity of > 8cm/s had a sensitivity of 69% and specificity of 85%. When these two velocities both exceed the limits above, such a combined index yielded a sensitivity of 69%, specificity of 94%, and an overall diagnostic accuracy of 86% for the estimation of preserved LV global function. The parameters derived from TDE profiles of inferior and anterior mitral annulus comers provide valuable information to predict preserved global left ventricular function during the early period of AAMI.     

Evaluation of a Doppler-derived index combining systolic and diastolic left ventricular function in acute myocardial infarction

Assessment of left ventricular (LV) function is crucial in the immediate postinfarction period. The authors evaluated the clinical applicability of the Doppler-derived myocardial performance index (MPI, defined as the sum of isovolumic contraction and relaxation times divided by LV ejection time) in patients with acute myocardial infarction (AMI) as to whether this index reflects the severity of LV dysfunction in this subgroup of patients. Post-AMI patients (n = 33) were compared with age- and sex-matched healthy subjects (n = 35). Within 24 hours of the AMI and 1 month thereafter, patients underwent 2D and Doppler echocardiography. Patients were divided into group A (Killip Class I, n = 22) and group B (Killip Class II-III, n = 11). The authors measured the LV ejection fraction (EF), diastolic indices (transmitral E and A waves, E/A ratio, deceleration time [DT], isovolumic contraction time [IVCT], isovolumic relaxation time [IVRT], MPI, LV end-systolic and end-diastolic volume indices [ESVi and EDVi] and wall motion score index [WMSi]). One-year mortality was also assessed. There was no significant difference concerning E and A waves, E/A ratio, and IVRT between the 2 groups. There were highly statistical differences at day 1 for EF (59.3 +/- 6.7% vs 36.8 +/- 4.5%, p<0.0001), DT (0.160 +/- 0.030 sec vs 0.127 +/- 0.022, p<0.005), MPI (0.344 +/- 0.084 vs 0.686 +/- 0.120, p<0.0001), ESVi (28.4 +/- 3.9 mL/m2 vs 46.2 +/- 8.4, p<0.001), and WMSi (1.58 +/- 0.06 vs 1.88 +/- 0.35, p=0.05), which persisted after 1 month. One-year mortality was significantly (0 vs 27.3%, p<0.01) lower in group A patients. This study shows that the MPI, reliably indicated LV dysfunction post-AMI, significantly correlated with clinically determined functional class, and possibly has some prognostic implication.     

Prognostic importance of hyponatremia in acute ST-elevation myocardial infarction

PURPOSE: To determine the prevalence and prognostic implications of hyponatremia in the setting of acute ST-elevation myocardial infarction. METHODS: The study sample consisted of 1047 consecutive patients presenting with acute ST-elevation myocardial infarction. Plasma sodium concentrations were obtained on admission and at 24, 48, and 72 hours thereafter. Infarct size was determined by echocardiographic examination that was performed on day 2 or 3 of hospitalization. RESULTS: Hyponatremia, defined as a plasma sodium level <135 mmol/L (<135 mEq/L), was present on admission in 131 patients (12.5%) and developed during the first 72 hours of hospitalization in 208 patients (19.9%). Plasma sodium levels decreased to < or = 130 mmol/L in 45 patients (4.3%). In a multivariate logistic regression analysis, hyponatremia was independently associated with 30-day mortality. The risk of 30-day mortality associated with hyponatremia on admission (odds ratio [OR] = 2.0; 95% confidence interval [CI]: 1.0 to 3.9; P = 0.04) was similar to that of hyponatremia developing after admission (OR = 2.4; 95% CI: 1.5 to 4.2; P = 0.002). The risk of 30-day mortality increased with the severity of hyponatremia, with an odds ratio of 2.1 in patients with sodium levels between 130 and 134 mmol/L (95% CI: 1.2 to 3.5; P = 0.007) and 3.4 in those with levels <130 mmol/L (95% CI: 1.5 to 7.8; P = 0.002). CONCLUSION: Hyponatremia on admission or early development of hyponatremia in patients with acute ST-elevation myocardial infarction is an independent predictor of 30-day mortality, and prognosis worsens with the severity of hyponatremia. Further studies are required to determine if plasma sodium levels may serve as a simple marker to identify patients at high risk.     

N-末端脑钠尿肽原诊断急性心肌梗死患者左室舒张功能的价值及其判断预后的意义

目的: 利用超声心动图,探讨N-末端脑钠尿肽原（NT-proBNP）对急性心肌梗死(AMI)患者左室舒张功能的评价及其意义。方法: 入选左室收缩功能正常的AMI患者66例,测定血浆NT-proBNP水平。根据组织多普勒超声（TDI）及二尖瓣血流频谱指标评价的左室舒张功能,将患者分为4组:A组:左室舒张功能正常组（n=16）;B组:轻度左室舒张功能减低（LVDD）组（n=21）;C组:中度LVDD组（n=24）;D组:重度LVDD组（n=5）。对患者随访12个月,临床终点是因心衰加重或再梗所致再住院和心源性死亡。结果: NT-proBNP水平随着LVDD的加重而显著增高（P<0.01）。NT-proBNP能够独立于其它影响因素判断LVDD,当其水平为962.1 μg/L时,判断LVDD的敏感性是76%,特异性是75%。12个月后发生终点事件患者的血浆NT-proBNP水平与未发生者相比差异有统计学意义（P<0.05）。结论: AMI后NT-proBNP水平能够独立评价LVDD并判断预后。它可用于对AMI患者危险分层并指导临床治疗。     

Prognostic value of left ventricular diastolic function and association with heart rate variability after a first acute myocardial infarction

OBJECTIVE—To study the prognostic value of left ventricular (LV) diastolic function and its relation with autonomic balance expressed by heart rate variability (HRV) in patients after a first acute myocardial infarction.
DESIGN—The study population consisted of 64 consecutive patients with first acute myocardial infarction and 31 control subjects. Long and short term HRV indices were evaluated by 24 hour Holter monitoring, and LV systolic and diastolic function were assessed by two dimensional and Doppler echocardiography before discharge. Patients were divided into two groups: those with restrictive LV filling characteristics (deceleration time  140 ms) and those with non-restrictive LV filling characteristics (deceleration time > 140 ms).
RESULTS—Both long and short term HRV indices were significantly reduced in patients with restrictive LV filling compared with the non-restrictive group and control subjects. Mitral deceleration time and isovolumetric relaxation time correlated weakly but significantly with all indices of HRV whereas ejection fraction correlated weakly with the long term HRV indices. The mean follow up time was 14.9 (8.7) months. Multivariate analysis showed that mitral deceleration time (χ² = 6.4, p < 0.001) and ejection fraction  40% (χ² = 4.4, p < 0.05) were independent predictors of cardiac death and readmission to hospital with congestive heart failure.
CONCLUSIONS—A restrictive LV filling pattern was found to be the strongest predictor of adverse outcome independent of HRV and ejection fraction during follow up after a first acute myocardial infarction. Patients with restrictive LV filling characteristics had more reduced HRV than those with non-restrictive diastolic filling.


Keywords: diastole; infarction; autonomic balance     

Prognostic importance of complete atrioventricular block complicating acute myocardial infarction

Third-degree atrioventricular block after acute myocardial infarction is considered to have prognostic importance. However, its importance in conjunction with thrombolytic therapy and its relation to left ventricular function remains uncertain. This report also outlines an important distinction between atrioventricular block in the setting of anterior and inferior wall acute myocardial infarction, with profound clinical and prognostic implications.     

Prognostic significance of systolic time intervals after recovery from myocardial infarction

This study tested the hypothesis that left ventricular global performance as assessed from systolic time intervals provides a prognostic indicator in patients with coronary artery disease. The ratio of preejection period to left ventricular ejection time ($\text{PEP}\text{LVET}$) was determined in 136 patients an average of 14.3 months (standard deviation 2 months) after a clinically documented acute myocardial infarction. The patients were followed up a minimum of 24 and an average of 43 ± 15 months. Coronary arteriography was performed within 48 hours of determination of the $\text{sol}\text{PEP}\text{LVET}$ ratio. The cumulative 5 year survival rate was 70 percent for the entire series; it was 93 percent for patients with a normal $\text{PEP}\text{LVET}$ ratio (0.42 or less) and 57 percent for patients with an abnormal ratio (greater than 0.42) (p < 0.001).There was diminishing cumulative survival with increasing extent of coronary arterial obstruction (p < 0.01). Among patients with a normal $\text{PEP}\text{LVET}$ ratio and one, two or three vessel disease, the 5 year survival rate was 97, 92 and 87 percent, respectively. Among patients with an abnormal $\text{PEP}\text{LVET}$ ratio, the respective rates were 82, 51 and 41 percent. Multivariate analysis of factors shown to vary significantly between groups with a normal or abnormal $\text{PEP}\text{LVET}$ ratio or to have independent prognostic value (age greater than 60 years, angina pectoris, dyspnea, multiple sites of myocardial infarction on electrocardiography, third sound gallop, and cardiothoracic ratio greater than 0.5 on chest roentgenography) revealed that only a cardiothoracic ratio greater than 0.5 added significant predictive information to that of the $\text{PEP}\text{LVET}$ ratio. The presence of dyspnea, a third or fourth sound gallop and a cardiothoracic ratio greater than 0.5, alone or in combination, did not permit accurate segregation of the patients with a normal or abnormal $\text{PEP}\text{LVET}$ ratio.Determination of the $\text{PEP}\text{LVET}$ ratio permits stratification of patients with a previous myocardial infarction into groups with markedly divergent survival patterns. The level of resting left ventricular performance in such patients constitutes a more potent prognostic indicator than does the extent of coronary arterial occlusive disease.     

Prognostic value of the Tei index combining systolic and diastolic myocardial performance in patients with acute myocardial infarction treated by successful primary angioplasty

Cardiac systolic (left ventricular ejection fraction) and diastolic (mitral inflow velocity pattern and/or mitral deceleration time) function were reported as predictors of clinical outcome or left ventricular remodeling in patients with acute myocardial infarction (AMI). Recently, a new index (Doppler-derived index combining systolic and diastolic myocardial performance; Tei index) for combined systolic and diastolic ventricular function has been reported to be a useful and convenient method for evaluation of global ventricular function. We therefore investigated the usefulness of the Tei index by echocardiography for evaluation of infarct size and clinical outcome in patients with AMI treated by successful primary angioplasty. We analyzed 10 age-matched control subjects and 43 consecutive patients with first AMI treated by successful primary angioplasty. The Tei index of the AMI patients was significantly greater than that of the control subjects (0.630 ± 0.106 vs 0.375 ± 0.036, P 0.0001). Also, the Tei index showed a significant positive correlation with peak creatine kinase values and ^99mTc-tetrofosmin scores. Moreover, multiple logistic regression analysis showed that the Tei index 0.70 (P = 0.0313, odds ratio = 14.14) was the only significant explanatory factor for cardiac death or developed congestive heart failure. The Tei index combining systolic and diastolic myocardial performance reflects infarct size and might be a predictor of clinical outcome in patients with AMI treated by successful primary angioplasty.     

Relation between exercise capacity and left ventricular systolic versus diastolic function during exercise in patients after myocardial infarction

BACKGROUND: It is known that left ventricular systolic function at rest does not correlate well with exercise capacity of patients with heart failure. However, the contribution of left ventricular diastolic dysfunction, especially during exercise, to exercise capacity of cardiac patients remains to be determined. OBJECTIVE: To determine the impact of left ventricular systolic and diastolic function during exercise on exercise capacity of patients with left ventricular dysfunction after myocardial infarction. METHODS: A symptom-limited exercise test was performed with measurements for hemodynamics and uptake of oxygen (Vo2) of 26 men who had previously suffered myocardial infarction. These patients were divided into two groups according to their peak Vo2 (group 1 with peak Vo2 > or = 16 ml/kg per min, n= 13; and group 2 with peak Vo2 < 16 ml/kg per min, n= 13). Pulmonary arterial pressure, left ventricular and systemic arterial pressure, and cardiac output were measured at rest and during exercise. RESULTS: At rest, there was no difference between the two groups in terms of hemodynamic parameters except for minimal dP/dt, minimal left ventricular pressure (LVP) and time constant for decay of left ventricular pressure (tau). During peak exercise, cardiac output, left ventricular end-diastolic pressure (EDP), minimal dP/dt, minimal LVP, and tau for the two groups were significantly different. Furthermore, peak Vo2 was significantly correlated with T, minimal LVP, minimal dP/dt, EDP, and maximal dP/dt during peak exercise for the whole group of patients. CONCLUSION: Left ventricular diastolic function during exercise, i.e. diastolic reserve, may be an important determinant of exercise capacity of patients with left ventricular dysfunction after myocardial infarction.     

Determinants of left ventricular systolic function after acute myocardial infarction: the role of residual myocardial ischaemia

BACKGROUND: Left ventricular systolic function (LVSF) is one of the major determinants of survival after acute myocardial infarction (AMI). Some factors such as the infarct size and localization, and the patency of the infarct-related artery are known determinants of LVSF. However, the long-term effect of myocardial ischaemia on LVSF has been poorly studied in clinical settings. OBJECTIVES: To assess the acute and long-term effects of myocardial ischaemia on LVSF in patients recovering from an AMI. METHODS: A cohort of 74 patients recovering from AMI was studied. Myocardial ischaemia was detected by means of ambulatory electrocardiogram (ECG) monitoring at recruitment (4+/-2 days after AMI), exercise ECG test and stress echocardiography at discharge (7+/-4 days after AMI). LVSF was studied by means of two-dimensional echocardiography at recruitment, at discharge, and at 1, 3, 6 and 12 months after AMI. RESULTS: Patients with myocardial ischaemia on ambulatory ECG monitoring and stress echocardiography had worse LVSF at recruitment than those without ischaemia. The presence of myocardial ischaemia on ambulatory ECG monitoring was an independent determinant of LVSF at recruitment together with infarct localization and size (assessed by creatine kinase MB isoenzyme (CK-MB) levels). Patients with signs of myocardial ischaemia on ambulatory ECG monitoring and stress echocardiography had a progressive left ventricular dysfunction compared with those without ischaemia. CONCLUSIONS: Residual ischaemia is an independent determinant of LVSF after AMI and its presence implied a progressive worsening of the LVSF. Because left ventricular systolic dysfunction is a major determinant of survival after AMI, its precursors, among them residual myocardial ischaemia, should be identified. Treatment of ischaemia is known to be associated with improved prognosis and improved LVSF.     

Prognostic importance of previous myocardial infarction in patients receiving thrombolytic therapy for acute infarction

This study evaluated the prognostic significance of reinfarction location by considering the previous site or type of myocardial infarction (MI) among 1601 patients with a history of previous MI who took part in the International (non-Italian) tPA/STK trial and/or the Israeli GUSTO study population. These patients were accordingly divided and hospital mortality was compared by six location groups as follows: acute inferior with previous inferior (8.1% hospital mortality), acute inferior with previous anterior (12.8%), acute anterior with previous inferior (13.3%), acute anterior with previous anterior (11.1%), acute inferior with previous non-Q-wave MI (7.6%), and acute anterior with previous non-Q-wave MI (11.2%) (p = 0.17 for comparison between the six groups). Hospital mortality tended to increase among patients with an anterior reinfarction compared with those with an inferior one (12.1% vs. 9.5%, p = 0.12). Among patients with a reinfarction at a different ECG location from the previous event, mortality tended to be higher compared with patients with two MIs at the same location (13.1% vs. 9.7%, p = 0.07). Recurrent MI following a previous Q-wave MI did not cause a higher mortality compared with a previous non-Q-wave type of MI (11.5% vs. 9.5%, p = 0.24). Among patients sustaining reinfarction, overall mortality did not differ between STK- and tPA-treated patients (11.0% vs. 11.4%, p = NS). In conclusion, the current study identified trends for higher mortality rates in patients with anterior compared with inferior reinfarction, with remote compared with the same ECG location of the two infarctions but not following a previous non-Q-wave compared with Q-wave MI. However, no particular combination of successive MIs location was significantly associated with a higher risk for hospital mortality.     

Prognostic importance of predischarged troponin T levels in acute anterior myocardial infarction

The baseline cardiac troponin T (cTnT) level strongly predicts short-term mortality in acute coronary syndromes, but the added value of predischarged (7th day) measures to predict short-term outcome and left ventricular (LV) remodeling in patients with ST elevation myocardial infarction (MI) is controversial. Baseline, peak and predischarged cTnT results were evaluated in 52 patients (15 females, 37 males, mean age, 54.4 +/- 8.8 years) with first acute anterior MI. There were 4 deaths (all cardiac origin) during the 30 day follow up period. Kaplan-Meier analysis revealed patients with a predischarged serum cTnT level higher than the median level (1.2 ng/mL) had a higher mortality rate than those with submedian levels (P < 0.05). Additionally, the highest correlation rate was found between predischarged cTnT values and LV ejection fraction (LV-EF, r = -0.58, P < 0.002). There were no differences between the groups in the 7th day left ventricular diastolic parameters, but the 30th day isovolumetric relaxation time and mitral E wave deceleration time were shorter (146.9 +/- 30.1 vs 129 +/- 23.4 msec, P = 0.025 and, 185.8 +/- 51.8 vs 144.6 +/- 58.1 msec, P = 0.012) in patients with higher predischarged cTnT level. High levels of predischarged cTnT levels in patients admitted with first acute anterior MI defines a subgroup. These patients have poor systolic and diastolic functions and are at increased risk of short term mortality. This group of patients may have benefit from early intensive treatment strategies before discharge.