Luigi Ascione

Myocardial global performance index as a predictor of in-hospital cardiac events in patients with first myocardial infarction

OBJECTIVE We sought to assess the ability of a Doppler index of global myocardial performance (MPI), measured at entry, to predict inhospital cardiac events in a series of patients with first acute myocardial infarction (AMI). METHODS A complete 2-dimensional and Doppler echocardiographic examination was performed within 24 hours of arrival at the coronary care department in 96 patients (81 men and 15 women; mean age 58 +/- 9 years) with first AMI. Patients were divided a posteriori into 2 groups according to their inhospital course: group 1 comprised 75 patients with an uneventful course and group 2 comprised 21 patients with a complicated inhospital course (death, heart failure, arrhythmias, or post-AMI angina). RESULTS There were no significant differences between the 2 groups with regard to history of hypertension, diabetes mellitus, hypercholesterolemia, site and size of infarction, and conventional parameters of diastolic function. However, patients with complications were significantly older (63 +/- 10 vs 55 +/- 8 years, P =.005) and had higher wall-motion score index and left ventricular end-systolic volume compared with patients without events (1.84 +/- 0.27 vs 1.52 +/- 0.30, P =.001; and 66 +/- 29 vs 47 +/- 21 mL, P =.009, respectively), whereas the ejection fraction was reduced (40 +/- 10% vs 52 +/- 10%, P =.0001). The mean value of the MPI was significantly higher in patients with cardiac events than in those without events (0.65 +/- 0.20 vs 0.43 +/- 0.16, P =.0001). A MPI >/= 0.47 showed a sensitivity of 90% and specificity of 68% for identifying patients with events, on the basis of the receiver operator curve. In a multivariable model, the MPI at admission remained independently predictive of inhospital cardiac events (odds ratio 15.6, 95% confidence interval 2.4-99, P =.003). CONCLUSION These data suggest that in the acute phase of AMI, the MPI measured at entry may be useful to predict which patients are at high risk for inhospital cardiac events.

Ultrasonographic assessment of basal coronary flow as a screening tool to exclude significant left anterior descending coronary artery stenosis.

Objective Coronary blood flow exhibits a biphasic pattern at rest with a higher diastolic and a smaller systolic component. In the present investigation, we evaluated whether a decreased diastolic to systolic velocity ratio of basal coronary flow may be useful in the identification of subjects with significant left anterior descending coronary artery (LAD) stenosis. Methods One hundred and twenty-nine consecutive patients (62 with unstable angina, 25 with acute myocardial infarction and 42 with chronic coronary artery disease) were included in the study. Blood flow velocities were recorded in the mid-distal portion of the LAD using an ATL 5000 CV HDI ultrasound system. All patients underwent coronary angiography and were divided into two groups according to the absence (group 1) or the presence (group 2) of significant LAD stenosis (lumen narrowing ≥ 70%). In 60 of the 129 patients, coronary flow reserve was evaluated non-invasively. Results Adequate Doppler recordings in the LAD were obtained by transthoracic echocardiography in 113 patients. There were no differences between groups with regard to sex, cardiovascular risk factors, left ventricular mass and volumes, ejection fraction, whereas the diastolic to systolic velocity ratio of basal coronary flow was significantly lower in group 2 patients (1.41 ± 4.7 vs. 2.08 ± 0.64, P < 0.00001). The receiver operating characteristic curve showed that a diastolic to systolic velocity ratio < 1.6 had a sensitivity of 77%, a specificity of 91%, a positive predictive value of 77%, a negative predictive value of 97%, and a diagnostic accuracy of 84% for the presence of significant LAD stenosis. In 55/60 patients, results of basal coronary flow and coronary flow reserve were concordant. On multivariate logistic regression analysis, the diastolic to systolic velocity ratio was a strong independent predictor of LAD stenosis ≥ 70% (odds ratio 4.90, 95% confidence interval 1.65–7.30). Conclusions The present findings suggest that assessment of basal coronary flow in the LAD may be useful to rule out the presence of significant stenosis.

Accuracy and feasibility of a simplified approach to assess the regurgitant orifice area in patients with mitral regurgitation

Background: Regurgitant orifice area (ROA) has been proposed as a marker of severity in patients with mitral regurgitation (MR). However, such fundamental quantitative echocardiographic parameter has failed to achieve widespread use, since it is difficult to measure. In the present study, we evaluated the accuracy and feasibility of a simplified method for quantification of ROA in patients with varying grades of MR. Methods: We studied two groups of individuals with echocardiographically diagnosed MR. Group I included 70 patients retrospectively evaluated, in whom we were able to obtain an adequate flow convergence region by color Doppler and recording of continuous-wave Doppler regurgitant jet. Group II included 32 MR patients prospectively evaluated. The degee of MR was assessed by two quantitative echocardiographic measures: the regurgitant fraction and the ROA, calculated either dividing peak flow rate by the maximal velocity through the orifice or with the simplified formula: r2/2. Results: In group I, the mechanism of MR was organic in 18 patients and ischemic/functional in 52 patients. ROA calculated by the simplified formula correlated well with the conventional one (r = 0.85) and with the regurgitant fraction (r = 0.72). In group II, we could calculate the ROA by the conventional method in 56% of patients, whereas use of the simplified approach allowed ROA evaluation in 78% of patients. Conclusion: Our data suggest that the use of a simplified formula may increase the number of patients having ROA, a fundamental parameter of MR severity, measured in clinical practice.

Usefulness of the mitral/aortic flow velocity integral ratio as a screening method to identify patients with hemodynamically significant mitral regurgitation

OBJECTIVE We sought to test the value of a simple Doppler index, the mitral/aortic flow velocity integral ratio (MAVIR), as a screening method to identify patients with hemodynamically significant mitral regurgitation (MR). METHODS Included in the study were 91 patients (mean age 61 +/- 14 years; 54% men) with echocardiographically diagnosed MR. The cause was organic in 23 patients and ischemic/functional in 68. MR degree was assessed by 2 quantitative echocardiographic measures: the regurgitant fraction and the regurgitant orifice area. RESULTS A good correlation was found between MAVIR and both regurgitant fraction (r = 0.75) and orifice (r = 0.60). When we divided patients into 3 groups on the basis of the regurgitant fraction, used as reference standard, MAVIR significantly increased in proportion to MR severity (0.7 +/- 0.1 for mild MR vs 1.1 +/- 0.2 for moderate and 1.4 +/- 0.3 for severe regurgitation; P <.0001). A ratio > 1 identified 28 of 30 patients with severe MR (regurgitant fraction > 60%), whereas all patients with mild MR (regurgitant fraction < 40%) had a ratio < 1. Using a regurgitant orifice >or= 40 mm(2) as threshold for severe MR, a significant difference in MAVIR was also present among patients who had severe MR compared with those having mild and moderate regurgitation (P <.0001). CONCLUSIONS These findings suggest that MAVIR is a sensitive index, potentially widely applicable in clinical practice as a screening parameter for identifying patients with hemodynamically significant MR.