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BACKGROUND: Non-alcoholic fatty liver disease (NAFLD) and left ventricular hypertrophy (LVH) are highly prevalent in Type 2 diabetes and both conditions are associated with an increased risk of incident cardiovascular disease. The aim of this study is to evaluate whether there is an association between NAFLD and echocardiographically detected LVH in Type 2 diabetes. METHODS: We studied 116 consecutive patients with hypertension and Type 2 diabetes after excluding those with pre-existing history of cardiovascular disease, advanced kidney disease, excessive alcohol consumption and other known causes of chronic liver disease (e.g., virus, medications, autoimmunity, iron overload). NAFLD was diagnosed by means of ultrasonography, whereas LVH was diagnosed by means of conventional trans-thoracic echocardiography in all patients. RESULTS: The prevalence of LVH was markedly higher among diabetic patients with NAFLD than among those without this disease (82% vs 18%; p=0.01). Multivariate logistic regression analysis revealed that NAFLD was associated with LVH independently of age, sex, body mass index, systolic blood pressure, glycated hemoglobin, duration of diabetes, and parameters of kidney function. CONCLUSIONS: Our findings suggest that hypertensive Type 2 diabetic patients with NAFLD have a remarkably higher frequency of LVH than do hypertensive diabetic patients without steatosis, and that NAFLD is associated with LVH independently of classical cardiovascular risk factors and other potential confounders.

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OBJECTIVE: To analyse the relation between restrictive mitral pattern, amino-terminal propeptide of type III procollagen (PIIINP), and prognosis in patients with dilated cardiomyopathy. DESIGN: Prospective cohort study of 106 patients with dilated cardiomyopathy. SETTING: Tertiary care centre. MAIN OUTCOME MEASURES: PIIINP concentration, echocardiographic variables, oxygen consumption, hospitalisation for heart failure, and cardiac mortality were evaluated in patients grouped by the presence of non-restrictive (group 1), reversible (group 2), and irreversible restrictive mitral pattern (group 3). RESULTS: Groups differed regarding left ventricular ejection fraction (group 1, mean (SD) 36 (6)%, group 2, 29 (8)%, group 3, 25 (6)%; p = 0.0001), left atrial ejection fraction (group 1, 0.47 (0.1)%, group 2, 0.43 (0.2)%, group 3, 0.26 (0.1)%; p < 0.0001), and PIIINP (p = 0.001). Multivariate analysis showed that PIIINP was related to mitral pattern (odds ratio 0.8, 95% confidence interval 0.23 to 1.4, p = 0.006) independently of left atrial and ventricular ejection fractions. After 21 months, survival was 88% and 34% (p = 0.0001) in patients with non-restrictive and irreversible restrictive mitral patterns, respectively. CONCLUSION: In patients with dilated cardiomyopathy, restrictive mitral pattern is associated with higher PIIINP and worse prognosis.

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BACKGROUND: Previous studies have reported the prognostic value of myocardial viability (MV) detected using low-dose dobutamine echocardiography (DbE). However, viability was frequently evaluated as improvement in regional wall motion score index, which includes increased function in hypokinetic segments, in which viable myocardium is necessarily present. It is not known whether an evaluation focusing on akinetic segments, in which the possible presence of viable myocardium is unknown, might have more prognostic value. The aim of this study was to compare the prognostic value of the improvement of myocardial function during dobutamine infusion in akinetic and hypokinetic regions in patients with acute myocardial infarction (AMI). METHODS: 191 patients with uncomplicated AMI and at least one akinetic segment were retrospectively selected from those consecutively examined at our echo-laboratory to evaluate MV using DbE. Myocardial viability was evaluated both as an increment in RWMSI (Delta RWMSI), which takes into consideration improvement in both akinetic and hypokinetic regions, and as an improvement of function in akinetic (Delta akinetic) and hypokinetic (Delta hypokinetic), segments considered separately. Follow-up evaluation was performed at 30+/-13 months. RESULTS: On the basis of the Delta RWMSI, 94/191 patients were judged to have myocardial viability, whereas considering myocardial viability in akinetic segments only, 72/191 patients showed viability. At follow-up 18 patients had died (six viable considering Delta RWMSI; three viable considering Delta akinetic). The presence of a previous AMI, the site of AMI, RWMSI and the number of akinetic segments, and Delta RWMSI and Delta akinetic were related to mortality at univariate Cox analysis. At multivariate stepwise Cox regression analysis Delta akinetic, but not Delta hypokinetic proved to be significantly related to mortality. The Kaplan-Meier survival curves were no different in patients with or without viable myocardium evaluated as Delta RWMSI, while they were significantly different considering patients with or without viability in akinetic segments (P=0.04). CONCLUSION: In conclusion our study confirms the prognostic importance of the evaluation of myocardial viability in infarcted patients. However, it points out that it is the presence of viability in akinetic segments that affects long-term survival in these patients. This supports the hypothesis that other mechanisms, above and beyond the effect on regional wall motion, are involved in the beneficial effects of myocardial viability.

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Enhanced early mitral flow and reduced systolic pulmonary vein flow may be caused both by increased left ventricular pressure as the result of diastolic dysfunction and by increased transmitral flow as the result of mitral regurgitation. Nevertheless, Doppler parameters are widely used to predict left ventricular filling pressure. We aimed to analyze the interference of mitral regurgitation with Doppler parameters usually used to estimate left ventricular filling pressure and to identify markers independent of mitral regurgitation, which could reliably estimate increased left ventricular filling pressure. Eighty-four patients (age, 62 +/- 9 years; 82% men) had a complete echocardiographic Doppler examination. Transmitral E- and A-wave velocity, E deceleration time and A duration, pulmonary vein systolic and diastolic velocities, and reversal flow duration and maximal and minimal left atrial volumes were measured. The difference between the duration of pulmonary vein and mitral A waves was calculated (A'-A). Mitral regurgitant volume was quantitatively assessed by echocardiography. Left ventricular end-diastolic pressure was measured invasively. Patients had a wide range of left ventricular ejection fraction (14% to 70%), mitral regurgitant volume (0 to 94 mL), and left ventricular end-diastolic pressure (3 to 37 mm Hg). E velocity, E/A, pulmonary vein systolic and diastolic, and systo-diastolic ratios were significantly and independently correlated with both left ventricular end-diastolic pressure and mitral regurgitant volume. A'-A showed a strong correlation with left ventricular end-diastolic pressure (r = 0.70; P <.0001), but the relation with mitral regurgitant volume was not significant (r = 0.19; P =.08). Mitral regurgitation affects the majority of Doppler parameters widely used to predict filling pressure but does not influence Ad'-Ad, which proved to be the strongest predictor of left ventricular end-diastolic pressure.

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OBJECTIVES: The objective of this study was to assess whether the angiotensin-converting enzyme (ACE) gene insertion/deletion (I/D) polymorphism influences the adequacy of the neurohormonal response to ACE inhibitors in patients with chronic heart failure (CHF). BACKGROUND: The renin-angiotensin-aldosterone system (RAAS) plays an important role in the pathophysiology of CHF, and aldosterone levels closely relate to outcome in patients with CHF. Angiotensin-converting enzyme inhibitors suppress the RAAS, but a significant proportion of patients exhibit elevated serum levels of aldosterone despite long-term administration of apparently adequate doses of these agents. METHODS: We prospectively studied 132 patients with CHF (ejection fraction <45%) receiving long-term therapy with ACE inhibitors for over six months. Patients taking aldosterone antagonists were excluded from the study. "Aldosterone escape" was defined as being present when plasma aldosterone levels were above the normal range in our laboratory (>42 nmol/L). Patients were then divided into two subgroups according to the presence (group 1) or absence (group 2) of aldosterone escape. Genotype analysis for the ACE I/D polymorphism was performed by polymerase chain reaction. RESULTS: The prevalence of aldosterone escape in our patients was 10% (13/132). The two groups of patients did not differ regarding the dose of ACE inhibitor, diuretics and their renal function. There was a statistically significant different distribution of genotypes between the two groups, with a higher proportion of DD genotype in group 1 compared with group 2 (62% vs. 24%, p = 0.005). CONCLUSIONS: Patients with CHF with aldosterone escape have a higher prevalence of DD genotype compared with patients with aldosterone within the normal limits. Angiotensin-converting enzyme gene polymorphism contributes to the modulation and adequacy of the neurohormonal response to long-term ACE-inhibitor administration in CHF.

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OBJECTIVES: We sought to assess whether skeletal muscle mass might be a predictor of peak oxygen consumption (Vo2) and relation of the ventilation to carbon dioxide production (VE/VCo2) slope in patients with chronic heart failure (CHF) independent of clinical conditions, neurohormonal activation and resting hemodynamics. BACKGROUND: A variety of abnormalities characterize skeletal muscle and contribute to exercise intolerance in patients with CHF. Skeletal muscle mass is a determinant of peak Vo2 both in healthy patients and in patients with CHF, but there are no reports on the independent predictive value of this parameter, which can be measured with great accuracy by whole-body dual energy X-ray absorptiometry (DEXA). The influence of skeletal muscle mass on VE/VCo2 slope is not known either. METHODS: We prospectively evaluated 120 consecutive noncachectic patients with CHF. Every patient underwent a cardiopulmonary exercise test, an echo-Doppler examination and an evaluation of neurohormonal activation and body composition as assessed by DEXA. RESULTS: At the univariate analysis, New York Heart Association (NYHA) class (p < 0.0001), age (p < 0.0001), male gender (p < 0.0001) and plasma renin (p < 0.0001) significantly related with peak Vo2. There was a significant correlation between lean mass and absolute peak Vo2 (r = 0.70, p < 0.0001) and VE/VCo2 slope (r = -0.27; p < 0.01). At the multivariate analysis, lean mass predicted peak Vo2 and VE/VCo2 slope independently of NYHA functional class, age, gender, neurohormonal activation and resting hemodynamics. CONCLUSIONS: Skeletal muscle mass is an independent predictor of peak Vo2 and VE/VCo2 slope in stable noncachectic patients with CHF. Future studies will determine whether an increase in skeletal muscle mass in the individual patient might result in an improvement in parameters of exercise capacity.

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In patients with dilated cardiomyopathy (DCM) of different aetiologies, a variable frequency of improvement in the left ventricular (LV) systolic function has been reported, while in patients with a 'classic' idiopathic DCM, the frequency of improvement is still under debate, and clinical and haemodynamic predictors of recovery of the LV function are needed. The aim of the present study was to determine the frequency of improvement in the LV systolic function in idiopathic DCM and to identify predictors of reversibility of the impaired LV contractility. A sample of 98 consecutive patients with idiopathic DCM was retrospectively evaluated. Echocardiographic and Doppler measurements were directly taken from the routine echo-report. LV systolic function was assessed semiquantitatively using a score index (SFSI). According to the improvement in the LV systolic function, the patients were divided into group 1 patients with improvement, and group 2 patients without improvement. During a follow-up of at least 12 months, 19 patients (19%) showed an improvement, with a significant increase in the mean SFSI; all these group 1 patients survived without heart transplant; in group 2, 18 patients (23%) died and 3 (4%) received a heart transplant. Patients in group 1 had a significantly shorter duration of symptoms (P=0.0045), a younger age (P=0.006), a shorter DtE (P=0.04), a lower SFSI (P<0.01), a worse NYHA class (P<0.001) and more frequently had a history of hypertension (P<0.0001). The same variables were significant predictors of improvement at the univariate analysis. At the multivariate logistic regression analysis, a shorter duration of symptoms (P=0.02), a history of hypertension (P=0.003), and a worse NYHA class (P=0.01) were independent predictors of improvement. A relatively large percentage of patients with an idiopathic DCM will have a marked improvement in the LV systolic function. This is more likely to happen in the presence of a short duration of symptoms and a history of hypertension. After an improvement, the prognosis is excellent.

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Mitral regurgitation (MR) after acute myocardial infarction (AMI) is an important prognostic factor. Although its mechanisms are still debated, ventricular remodeling probably plays an important role. Because myocardial viability (MV) in the infarct zone reduces infarct expansion and ventricular remodeling, it is also possible that its presence counteracts the development of mitral regurgitation in infarcted patients. To evaluate this issue 191 patients with uncomplicated AMI, wall motion abnormalities (akinesis) and semiquantitative evaluation of MR were retrospectively selected from those consecutively examined at our echo-laboratory to evaluate MV using low-dose dobutamine echocardiography (DbE). Follow-up evaluation was performed at 30+/-13 months. Seventy-nine patients had no MR; 86 patients had grade 1 MR, 11 patients had grade 2 MR, nine patients had grade 3 MR, and six patients had grade 4 MR. Patients with significant MR (>grade 1) were older (63+/-7 vs. 59+/-10 years, P=0.03), had lower reduction of RWMSI (DeltaRWMSI) during DbE (0.08+/-0.11 vs. 0.22+/-0.28, P=0.01), more stenotic vessels at coronary angiography (2.35+/-0.93 vs. 1.67+/-1.12, P=0.01), and more frequently had anterior-inferior AMI (P<0.0001); they also had a non-significant tendency to higher RWMSI (2.04+/-0.38 vs. 1.92+/-0.28, P=0.06). In a multivariate regression analysis, DeltaRWMSI proved to be significantly related to the grade of MR (P=0.02). Eighteen patients died during follow-up. Death was more frequent in patients with MR (10/165 vs. 8/26, P=0.0003). At multivariate stepwise Cox regression analysis both the extent of ventricular dysfunction and the presence of MR were significantly related to mortality (P<0.0001 and P=0.01, respectively); DeltaRWMSI showed a non-significant tendency to influence mortality (P=0.09). When MR was excluded from the multivariate analysis, DeltaRWMSI remained significantly related to mortality (P=0.05). In conclusion our study suggests that the presence of MV in infarcted patients influences the development of MR. This reduction of MR may be one of the mechanisms by which MV affects mortality after AMI and should be considered in all studies that evaluate MV after myocardial infarction.

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This study was conducted to assess the accuracy of the estimated mitral regurgitant volume using both the left atrial filling volume and the systolic component of pulmonary vein flow expressed as the percent of its total. Since mitral regurgitation fills the left atrial chamber, the variation in atrial volume during ventricular systole has been proposed as a means to evaluate the severity of regurgitation. Although the correlation with invasive grading of mitral regurgitation is good, there is an unacceptable overlap among grades caused by the absence of information concerning pulmonary vein flow, which enters the left atrium while regurgitation occurs. The Doppler regurgitant volume, or Dp-RVol (mitral stroke volume minus aortic stroke volume) was quantified in 74 patients with any degree and etiology of mitral regurgitation. Atrial volumes were measured from the four-chamber apical view (biplane area-length method). The systolic time-velocity integral of pulmonary vein flow was expressed as the percent of the total (PVs%) (systolic-diastolic) time-velocity integral. These parameters were subjected to multivariate analysis and a regression equation was obtained. The equation was subsequently applied to a group of 31 patients without mitral regurgitation, as evaluated by color Doppler or continuous-wave Doppler and to the overall population (105 patients) in order to estimate the mitral regurgitant volume. In 74 patients with mitral regurgitation, the Doppler regurgitant volume was univariately correlated with the left atrial filling volume (r= 0.74; p<0.0001) and the systolic pulmonary vein velocity integral expressed as the percent of the total (r=0.67; p<0.0001). In multiple regression analysis, the combination of atrial filling and the pulmonary vein velocity integral provided the more accurate estimation of the regurgitant volume (R2=0.84; standard error of the estimate [SEE], 13.9 mL; p<0.0001; Dp-RVol equals 7.84+[1.08*left atrial filling volume] 2 [0.839*PVs%]). In 31 patients with no mitral regurgitation detected by color Doppler or continuous wave Doppler the estimated regurgitant volume was 4.3±6.6 mL. In the overall population the estimated regurgitant volume and the Doppler regurgitant volume correlated well with each other (R2=0.85; SEE, 11.5 mL; p<0.0001). The equation was 100% sensitive and 98% specific in detecting a regurgitant volume higher than 55 mL. The combination of the atrial filling volume and the systolic pulmonary vein time-velocity integral expressed as the percent of the total allows reliable estimation of the regurgitant volume in patients with mitral regurgitation. (c)2001 CHF, Inc.

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BACKGROUND: An echocardiographic assessment of left ventricular (LV) diastolic dysfunction is still challenging when identifying a pseudonormal mitral pattern (PSE) in an unselected population. The present study analyzed and compared the accuracy of various parameters in correctly identifying a PSE pattern in patients with a broad range of ejection fraction (EF) and degree of mitral regurgitation. METHODS: Eighty-two patients with E/A > or = 1 and an invasive determination of left ventricular end-diastolic pressure (LVEDP) were enrolled in the study. Mitral E wave (E(max)) and A (A(max)) velocities, E (DTe) and A (DTa) deceleration times, pulmonary vein systolic and diastolic velocities, and time velocity integrals were measured. The different duration between mitral and pulmonary vein A wave (A'-A) also was calculated. E(max) and E/A during Valsalva maneuver were measured and expressed as percentage compared with baseline. LV end-diastolic (LVD), end-systolic (LVS), and EF were measured from the apical four-chambers view (area-length method). Left atrial end-systolic (LA(max)) and end-diastolic (LA(min)) were measured from the apical four- and two-chambers views (area-length method). Left atrial filling volume (LA(fill)) was the difference between LA(max) and LA(min). Mitral regurgitant volume was estimated by the following equation: MR(vol) = 6.18 + (1.01 * LA(fill)) - (0.783 * PVs %). RESULTS: Thirty-two patients (age: 55 +/- 21 years; 75% male) had LVEDP < or = 18 mmHg and were classified as normal mitral pattern (Group 1). Fifty patients (age: 57 +/- 22 years; 76% male) had LVEDP > 18 mmHg, and were classified accordingly as having PSE (Group 2). At logistic univariate analysis, DTa (0.005), LV EF (0.01), A'-A (< 0.0001) and % E/A (0.03) were the more powerful predictors of PSE. A'-A had the highest global accuracy in identifying PSE in patients with reduced (90%) and normal (88%) LV EF. CONCLUSION: A'-A has the highest accuracy in identifying PSE in an unselected population. This parameters should be implemented in routine echocardiography since it allows additional information about LV diastolic function assessment.

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BACKGROUND: The onset of symptoms is crucial in the natural history of severe aortic stenosis. In contrast, the impact of the degree of valve obstruction and left ventricular dysfunction on clinical outcome in terms of progression of symptoms and mortality is undefined. METHODS AND RESULTS: Between April 1989 and June 1996, 108 patients (75% male, aged 68.7 +/- 10.3 years) with pure and isolated aortic stenosis of at least moderate degree had a complete Doppler echocardiography. Left ventricular end-diastolic and end-systolic diameters, thickness of ventricular septum, mass and ejection fraction, and maximal instantaneous aortic gradient were measured. Patients were followed up through March 1999. Sixty-five patients who underwent aortic valve replacement were censored at the time of surgery. The end point was considered to be death or symptomatic progression (onset of new symptoms or worsening of symptoms). At the time of diagnosis 64 (59%) were in New York Heart Association (NYHA) class I-II and 44 (41%) in NYHA class III-IV. After a mean follow-up of 46 +/- 21 months 6 patients died and 45 had worsening of symptoms. Univariate predictors of clinical outcome (death and worsening of symptoms) included left ventricular end-diastolic diameter (hazard ratio 1.03, P =.08), left ventricular end-systolic diameter (HR 1.04, P =.012), and left ventricular septum thickness (HR 1.14, P =.009) but not the degree of aortic obstruction. Multivariate predictors of clinical outcome were left ventricular septum thickness (P =.016) and left ventricular end-systolic diameter (P =.008). CONCLUSION: In patients with various degrees of aortic stenosis the rate of clinical outcome is predicted by left ventricular function and septum thickness. Therefore both the left ventricular and aortic valve gradients should be taken into account when choosing the timing of intervention.

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Although surgery is highly effective for symptomatic relief in patients with aortic stenosis, symptoms of congestive heart failure may be still present postoperatively. This group of patients with aortic stenosis is characterized by a wide range of left atrial size, which can predict postoperative symptomatic improvement.

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AIM: To compare the predictive value of thallium-201 single photon emission computed tomography (SPECT) scintigraphy (Sci) and low-dose dobutamine echocardiography (Dob) in predicting late recovery of dysfunctioning myocardium in patients with recent, uncomplicated myocardial infarction (MI). METHODS AND RESULTS: 19 patients (18 male, aged 58+/-8 years) with recent MI and ejection fraction <50% (35.5+/-8.3%) underwent 5-15 microg/kg per min Dob, rest-redistribution Sci and coronary angiography, respectively, 14+/-6, 16+/-7 and 17+/-5 days after MI. On an eleven-segment ventricular model devised to compare Dob and Sci segment by segment, each dysfunctioning ventricular segment was considered viable if it showed recovery of mechanical function at the echocardiographic follow-up, performed 6.3+/-1.5 months after revascularization (five PTCA, five GABG) or medical therapy. Among the 104 dysfunctioning segments, of which 26 (25%) showed recovery at follow-up, Dob and Sci gave a concordant response in 50 (48%, k = 0.13), correctly predicting the recovery (or not) of function in 42. Forty-two of 54 discordant responses were due to segments judged viable only by Sci and which had no recovery at follow-up (of these 37 were akinetic or severely hypokinetic at baseline). At the segment-by-segment analysis, the sensitivity, specificity, and accuracy in predicting recovery of function at follow-up were, respectively, 69, 88 and 84% for Dob as against 88, 36 and 49% for Sci (P<0.001 for both specificity and accuracy, P=NS for sensitivity). CONCLUSION: In patients with recent MI, the specificity of Dob in the detection of myocardium capable of late mechanical recovery is significantly higher with respect to Sci, whereas sensitivity is slightly, not significantly higher for the latter. It is conceivable that Sci detects viable myocardium even if it is transmurally limited to epicardial layers in segments with severely impaired mechanical function in which viability will not affect late recovery of function.

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OBJECTIVES: The objective was to analyze the accuracy and diagnostic value of the estimated regurgitant volume of mitral regurgitation using 1) left atrial volume variation during ventricular systole (left atrial filling volume) and 2) the percent of systolic pulmonary vein velocity integral compared with its total. BACKGROUND: Left atrial filling volume (LAfill), which represents the atrial volume variation during ventricular systole, has been used for the assessment of mitral regurgitation severity. A good correlation with invasive semiquantitative evaluation was found, but with an unacceptable overlapping among grades. The reason could be the absence of information concerning the contribution of blood entering into the left atrium from the pulmonary veins. METHODS: Doppler regurgitant volume (Dpl-RVol) (mitral stroke volume - aortic stroke volume) was measured in 30 patients with varying degrees and etiological causes of mitral regurgitation. In each patient atrial volumes were measured from the apical view, using the biplane area-length method. The systolic time-velocity integral of pulmonary vein flow was expressed as a percentage of the total (systolic-diastolic) time-velocity integral (PVs%). These parameters were used in this group of patients to obtain an equation whose reliability in estimating Dpl-RVol was tested in a second group of patients. RESULTS: In the initial study group, with linear regression analysis the following parameters correlated with Dpl-RVol: end-systolic left atrial volume (R2=0.37, p=0.0004); LAfill (R2=0.45, p < 0.0001); PVs% (R2=0.56, p < 0.0001). In multiple regression analysis the combination of LAfill and the percent of the systolic pulmonary vein velocity integral (PVs%) provided a more accurate estimate of regurgitant volume (R2=0.88; SEE 10.6; p < 0.0001; Dpl-RV=6.18 + (1.01 x LAfill) - (0.783 x PVs%). The equation was subsequently tested in 54 additional patients with mitral regurgitation with a mean Dpl-RVol 27+/-37 ml. Estimated regurgitant volume and Dpl-RVol correlated well with each other (R2=0.90; SEE 12.1; p < 0.0001). In the test population, the equation was 100% sensitive and 98% specific in detecting a regurgitant volume higher than 55 ml. CONCLUSIONS: Left atrial filling volume and pulmonary vein flow give a reliable estimate of regurgitant volume in mitral regurgitation.

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BACKGROUND: The FAMIS (Fosinopril in Acute Myocardial Infarction Study) was a multicenter, placebo-controlled, double-blind trial designed to evaluate the safety and the efficacy of fosinopril in reducing left ventricular enlargement after acute anterior myocardial infarction. We evaluated the echocardiographic examinations performed during the trial in order to assess the trend of the remodeling process over time and to evaluate the role of infarct size in identifying patients at risk of progressive left ventricular dilation. METHODS: A complete echocardiographic examination was performed on admission, before discharge and three months later. Patients undergoing coronary bypass surgery or PTCA had a further examination prior to the procedure. The echocardiograms were analyzed at a central laboratory, and the end-diastolic and end-systolic left ventricular volumes were computed by using a modified Simpson's rule technique. Regional wall motion was evaluated using the centerline method, analyzing the left ventricular boundary along 100 chords perpendicular to the centerline constructed midway between the end-diastolic and the end-systolic contours. A quantitative infarct-size index was then computed according to the number of chords with a fractional shortening equal to or less than 5%. RESULTS: Left ventricular end-diastolic and end-systolic volume index significantly increased over time (p < 0.0001); as a result, the stroke volume increased (p < 0.0001) but the ejection fraction did not change. Patients were then divided according to the three-month infarct-size index. For both end-diastolic and end-systolic volume, not only did larger infarcts had higher volumes, but there was also a greater increase from baseline to 3 months. Moreover, larger infarcts had a lower ejection fraction, with a further reduction over the three months, while smaller infarcts had higher values and an increase over time. An infarct-size index of 25 or larger allowed prospective identification at the baseline examination of patients at risk of subsequent left ventricular dilation. CONCLUSIONS: In conclusion, patients at greatest risk of left ventricular dilation, namely those with larger infarct size, constitute a group that is worth considering for any therapeutic effort for reducing the remodeling process. These patients could in fact benefit from therapeutic strategies aimed at the reduction of left ventricular remodeling and should be studied in clinical trials.

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BACKGROUND: Recent studies have reported that adequate perfusion of the infarct-related artery improves survival in patients with myocardial infarction, independently of left ventricular pump function. However, it is not known whether or not this reduction in mortality is independent of myocardial viability within the infarct zone. The aim of this study was to evaluate the prognostic value of the patency of the infarct artery and the presence of myocardial viability in akinetic regions in patients with myocardial infarction. METHODS: Low-dose dobutamine echocardiography was performed in 154 patients with recent or previous myocardial infarction and known coronary anatomy. In each patient three vascular regions were defined. Each akinetic region was considered viable if function improved during dobutamine echocardiography, and irrorated by a not stenotic akinetic area-related artery if the supplying vessel had a stenosis < 75% or had been successfully revascularized within 1 month of dobutamine echocardiography. RESULTS: At follow-up of 34 +/- 14 months, 19 patients died of cardiac death. At univariate Cox analysis end-diastolic and end-systolic volumes, ejection fraction, previous myocardial infarction, regional wall motion score index, and stenosis of the akinetic area-related artery were related to mortality. At multivariate analysis, stenosis of the akinetic area-related artery remained a significant predictor of mortality (p = 0.04), with higher mortality (13/66 vs 6/88, p = 0.02) in patients with a stenotic akinetic area-related artery, without differences in ejection fraction (35 +/- 9 vs 34 +/- 10%). Mortality was lower in patients with myocardial viability if they had a not stenotic akinetic area-related artery (1/43 vs 4/21, p = 0.02), while no difference was found among non-viable patients, with or without stenosis of the akinetic area-related artery (5/45 vs 9/45). CONCLUSIONS: The present study confirms the prognostic role of the patency of the infarct-related artery. However, it suggests that the lower mortality in patients with a patent artery supplying akinetic infarcted regions is related to the presence of myocardial viability in these regions.

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BACKGROUND: Myocardial perfusion in the risk area during the acute phase of myocardial infarction has been extensively investigated over the last few years. The so-called "no-reflow" or "low-reflow phenomenon" (absence of myocardial perfusion despite patency of the infarct-related coronary artery) was shown to correlate with worse postinfarction remodeling, in particular when myocardial contrast echocardiography was used. The aim of this study was to determine, during routine coronary angiography performed before and after coronary angioplasty (PTCA) during the acute phase of myocardial infarction, the existence of the no-reflow phenomenon and its relation with ventricular remodeling, by evaluating the dye video density in the myocardial risk area. This confirmation by a different diagnostic technique may serve to highlight the role of myocardial perfusion as an index of prognosis in the clinical setting of acute myocardial infarction. METHODS: Twenty-six patients (23 males, 3 females, mean age 57 +/- 8.7 years) who underwent either rescue (n = 11, 42.3%) or primary PTCA, according to clinical indications, of the left anterior descending coronary artery during an acute anterior myocardial infarction and who did not have stenosis of the left circumflex or right coronary artery, were retrospectively selected from a 6 year intake. The extent of coronary stenosis was assessed using biplane quantitative coronary angiography, while end-diastolic and end-systolic volume indexes, together with regional wall motion, were computed from echocardiography performed in the first 24 hours and at 6 months. Patients were subdivided into two groups on the basis of dye video intensity in the risk area, as assessed from images obtained during left main coronary artery injections before and immediately after PTCA. It was used a subtraction technique (Group A: increased video intensity, n = 12; Group B: no change, n = 14), assuming that higher peak intensity reflects greater myocardial blood volume. Three patients in Group B with ineffective PTCA were excluded, so that the final number of considered patients was 11. RESULTS: The distribution of rescue PTCA was similar in the two groups (7 in Group A vs 3 in Group B, p = 0.13) as were clinical characteristics and therapeutic regimen. There was a significant time * group interaction for end-diastolic volumes (-4.6 +/- 23% in Group A vs +22 +/- 22% in Group B, p = 0.029), whereas end-systolic volumes showed a tendency to greater dilation in Group B (+19 +/- 28% vs +0.9 +/- 31% in Group A), although this difference was not significant (p = 0.27). No interaction was evident for increase in the vessel area (+46 +/- 12.5% in Group A vs +43.2 +/- 13.6% in Group B, p = 0.99), or for extent of regional dysfunction (+3.08 +/- 10.9 chords in Group A vs -2.5 +/- 9.5 chords in Group B, p = 0.50). CONCLUSIONS: The detection of myocardial blood volume in the risk area using dye video intensity during left main dye contrast injection, is useful to distinguish whether there is improved perfusion at the muscular level, following successful angioplasty of the infarct-related coronary artery. Lack of improved myocardial perfusion has an adverse effect on left ventricular volumes independently of coronary stenosis resolution and regional wall motion changes in the time.

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Revascularization can improve ventricular function in patients with viable myocardium, but whether and how the presence of viable myocardium affects prognosis of infarcted patients is still far from clear. Thus, 202 patients (173 men, 59 +/- 9 years old) with a previous or recent myocardial infarction (MI) and regional asynergies underwent low-dose dobutamine echocardiography (5-15 microg/kg per min) to assess myocardial viability and were followed for a period of 16 +/- 11 months after revascularization (89 patients) or medical therapy (113 patients). Four groups of patients were defined: (1) patients with viability, revascularized (n = 64); (2) patients with viability, treated medically (n = 52); (3) patients without viability, revascularized (n = 25); and (4) patients without viability, treated medically (n = 61). Of these patients, 45 (23%) patients suffered 57 cardiac events: 18 cardiac deaths (9%), 7 MIs, 12 unstable angina, 9 heart failures, and 11 new revascularization procedures. Patients with viability, revascularized, experienced a slightly lower event rate (22%) compared with patients with viability, treated medically, patients without viability, treated medically and patients without viability, revascularized (29%, 31%, and 36%, respectively; p = not significant [NS]). The frequency of events was then evaluated in those 108 patients with an ejection fraction < or =33%, in whom 14 cardiac deaths occurred: the incidence of cardiac death was slightly lower in patients with viability, revascularized (3/37, 8%) than in the patients with viability, treated medically (4/26, 15%), patients without viability, revascularized (2/11, 18%), or patients without viability, treated medically (5/34, 15%) (p = NS). Nonfatal cardiac events were significantly fewer (p <0.05) in patients with viability, revascularized (8%) and in patients without viability, treated medically (6%) than in patients with viability, treated medically and patients without viability, revascularized (27%). In infarcted patients with severe left ventricular dysfunction, the presence of viable myocardium, if left unrevascularized, leads to further events. On the contrary, in the absence of myocardial viability, revascularization could lead to a worse prognosis than medical therapy.

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