The clinical value of mitral A-wave deceleration time in the prediction of a long-term adverse outcome in patients with myocardial infarction

INTRODUCTION

Mitral A-wave deceleration time (Adt) is a promising Doppler parameter for the evaluation of left ventricular (LV) diastolic function. The aim of the present study was to investigate the long-term prognostic value of Adt in relation to the development of heart failure and cardiac death in the setting of the first acute myocardial infarction (MI).

METHODS

Conventional Doppler echocardiographic study and Adt measurements were performed in 105 patients (age 60 +/- 10 years, 77 men) 8.07 +/- 0.96 days post MI. Patients were divided into three groups according to Adt duration: group 1 with Adt > or =70 ms, group 2 with 70 ms < Adt <115 ms, and group 3 with Adt > or =115 ms.

RESULTS

Patients of groups 1 (Adt: 64 +/- 5 ms, n=11) and 3 (Adt: 123 +/- 8 ms, n=38) presented characteristics of restrictive physiology or impaired relaxation, respectively, while patients of group 2 (Adt: 92 +/- 9 ms, n=56) had near to normal LV filling characteristics. Patients were followed up for a mean of 44.7 months. Heart failure was found in 4 patients (36%) in group 1 and 6 (16%) in group 3, whereas the patients in group 2 were free of heart failure. Cardiac death occurred in 4 patients (36%) in group 1, 3 (7.9%) in group 3 and 2 (3.6%) in group 2. Kaplan-Meier survival curves indicated that patients with Adt < or =70 ms or Adt > or =115 ms had more frequent cardiac events and a significantly shorter event-free survival period in comparison with those with 70 ms < Adt < 115 ms (p = 0.0017). Cox analysis showed that Adt < or =70 ms (p = 0.002), Adt > or =115 ms (p = 0.02), restrictive LV filling pattern (p = 0.003), anterior wall MI (p = 0.02), ejection fraction (p = 0.03), age (p = 0.04), and treatment with angiotensin converting enzyme inhibitors (p = 0.009) were independent predictors of outcome.

CONCLUSIONS

Adt appears to be a strong and independent predictor of heart failure or cardiac death following a MI. A shortened Adt < or =70 ms is associated with higher rates of both cardiac death and heart failure, while a prolonged Adt > or =115 ms is associated with heart failure only.

The influence of thrombolytic therapy on C-reactive protein in ST-segment elevation acute myocardial infarction

BACKGROUND

Inflammation plays a crucial role in atherosclerotic processes and in acute coronary syndromes (ACS). Strong evidence of this is the elevation of C-reactive protein (CRP) serum levels during an ACS and its short- and long-term prognostic potency. The present study aimed to assess the relation between CRP serum levels and the elevation of cardiac markers in patients with ST elevation acute myocardial infarction (STEMI) as well as the effect of intravenous thrombolysis on a time series of CRP values.

METHODS

Thirty-six patients with STEMI were enrolled in the study. Twenty-eight of them received intravenous thrombolysis successfully and 8 did not receive thrombolysis. We measured serum concentrations of CRP, troponin I, creatine kinase, creatine kinase isoenzyme and lactate dehydrogenase in all patients on admission, 24 and 48 hours later. CRP serum values were obtained using the turbidimetric method. Coronary angiography was performed in all patients to estimate disease severity and culprit vessel flow after treatment.

RESULTS

Patients who were thrombolysed had lower CRP values on admission (p < 0.05), at 24 hours (p < 0.001) and 48 hours later (p < 0.05), compared to those without thrombolysis. CRP values on admission had a positive correlation with markers of cardiac myocyte necrosis and a negative correlation with TIMI flow.

CONCLUSION

Thrombolytic therapy in patients with STEMI is associated with a less pronounced response of CRP during the first 48 hours. The close relation of CRP with cardiac enzymes and troponin I on admission adds to the proven value of this inflammatory marker and suggests directions for further research.

Influence of angiotensin II receptors blocking on overall left ventricle's performance of patients with acute myocardial infarction of limited extent. Echocardiographic assessment

INTRODUCTION

Recent studies documented the beneficial effect of angiotensin-receptor blockers (ARBs) on patients (pts) with acute myocardial infarction (AMI) combined with left ventricle (LV) systolic dysfunction. The present study intended to assess the impact of the ARB irbesartan, on the overall LV performance in pts with uncomplicated AMI of limited extent.

METHODS

Forty consecutive pts with first inferior AMI (AMI-I) and preserved LV-systolic function were enrolled. They were allocated into two groups: (a) 20 pts received the conventional treatment of AMI-I and placebo (CT) and (b) 20 pts administered irbesartan additionally to the conventional treatment (IR). Twenty four healthy individuals of matching age and sex were recruited as control group (CG). Complete echocardiographic examination, Tei index of overall LV function and systolic blood pressure (SBP) were measured on the 8th post-infarct day.

RESULTS

The Tei index of IR group (0.53+/-0.03) was significantly lower compared to that of CT group (0.78+/-0.05) (p<0.001) and was similar to that of CG (0.45+/-0.03)(p=NS). Irbesartan induced a considerable decrease in both isovolumic relaxation (115+/-7 ms vs 140+/-7 ms; p<0.01) and contraction time (52+/-2 ms vs 64+/-3 ms; p<0.01) and a significant increase in ejection time (279+/-6 ms vs 256+/-8 ms; p<0.05). SBP in pts of IR group was similar to that of CT group (112+/-3 mmHg vs 113+/-4 mmHg; p=NS).

CONCLUSIONS

Therapy with Irbesartan improves overall LV function of pts with AMI-I. Irbesartan leads to acceleration of the LV relaxation, which possibly indirectly ameliorates LV systolic performance too. This beneficial influence is possible attributed to a direct tissue effect of the drug and not to its hemodynamic action.

Tei index as a method of evaluating left ventricular diastolic dysfunction in acute myocardial infarction

INTRODUCTION

The Doppler index of overall left ventricular (LV) myocardial performance--the Tei index--has been shown to be a reliable indicator of all changes in LV systolic dysfunction, retaining an inverse relationship with the ejection fraction. The aim of this study was to examine the corresponding behaviour in relation to LV diastolic dysfunction in patients with acute myocardial infarction (AMI), a relationship that has not been studied previously.

METHODS

The study included 105 patients (77 men) with first AMI who were classified into four groups according to the severity of LV diastolic dysfunction: a) 25 patients with normal diastolic function (NDF), b) 36 with decreased peak filling rate pattern (DFR), c) 33 with impaired relaxation (IR) and d) 11 with pseudonormal or restrictive physiology (PN/RP). A complete echocardiographic study, including all conventional systolic and diastolic echo/Doppler parameters as well as measurement of the Tei index, was performed on the eighth post-infarction day (mean 8.07 +/- 0.96 days) in all patients.

RESULTS

In the patients with IR (0.77 +/- 0.05) the index was significantly greater than in those of the NDF (0.55 +/- 0.03, p<0.01) or DFR (0.65 +/- 0.02, p<0.01) groups. The index in the DFR group was greater than in the NDF group, though not significantly so. In contrast, the index in the PN/RP patients (0.59 +/- 0.05) was significantly lower than in the patients with IR (p<0.01), whereas it did not differ from that of the patients in the NDF or DFR groups ("pseudonormalisation" of the index).

CONCLUSIONS

The Tei index detects with reliability milder types of diastolic dysfunction. However, because of its "pseudonormalisation" in patients with PN/RP, the Tei index cannot be considered a reliable indicator of more severe patterns of LV diastolic dysfunction in AMI patients.

Influence of perindopril on left ventricular global performance during the early phase of inferior acute myocardial infarction: assessment by Tei index

The beneficial effect of angiotensin-converting enzyme inhibitors (ACE inhibitors) on left ventricular (LV) function in patients with acute myocardial infarction (AMI) is widely known. However, controversy exists about their efficacy on patients with small infarcts and preserved LV systolic function. The aim of the present study was to detect the influence of the ACE-I perindopril on the global LV performance in patients with pure inferior AMI (AMI-I) using a Doppler-derived index (DI) that combines systolic and diastolic time intervals (Tei index). Our study included 40 patients with first AMI-I, mean age 60 years +/- 9.06 years (SD) and 24 age- and gender-matched normal patients who constituted the control group (COG). Patients were randomized into two groups to receive the conventional treatment of AMI-I (GCT) or the above therapy plus P (GP). Complete Doppler echocardiography (systolic and diastolic parameters), DI, and systolic blood pressure (SBP) were measured on the 8.07 +/- 1.16(SD) post-infarct day. The same examination was performed to COG. The DI was significantly lower in healthy patients(0.45 +/- 0.23)compared with the value in patients of either GP(0.56 +/- 0.03; P = 0.023)or GCT(0.78 +/- 0.05; P = 0.000). Moreover DI was higher in patients of GCT compared with that of GP(P = 0.000). In addition, perindopril administration decreased isovolumic relaxation time(IRT; 120.00 +/- 4.23 vs. 139.00 +/- 6.74; P = 0.006)and increased significantly ejection time (ET;274.25 +/- 7.35 vs. 253.50 +/- 7.68; P = 0.042). SBP in patients of GP was similar to that of GCT(120.5 +/- 2.85 mmHg vs. 112.5 +/- 3.49 mmHg; P = NS).

CONCLUSIONS

Global LV function (DI) is impaired in patients with AMI-I. Administration of perindopril has a favorable impact on LV performance in patients with AMI-I, achieved through improvement of the diastolic function (IRT), which indirectly improves LV systolic function (ET, DI). This beneficial influence of perindopril is the result of the direct tissue effect of the drug and not its hemodynamic action.