Piercarlo Ballo

Speckle-Tracking Echocardiography A New Technique for Assessing Myocardial Function

Speckle‐tracking echocardiography has recently emerged as a quantitative ultrasound technique for accurately evaluating myocardial function by analyzing the motion of speckles identified on routine 2‐dimensional sonograms. It provides non‐Doppler, angle‐independent, and objective quantification of myocardial deformation and left ventricular systolic and diastolic dynamics. By tracking the displacement of the speckles during the cardiac cycle, strain and the strain rate can be rapidly measured offline after adequate image acquisition. Data regarding the feasibility, accuracy, and clinical applications of speckle‐tracking echocardiography are rapidly accumulating. This review describes the fundamental concepts of speckle‐tracking echocardiography, illustrates how to obtain strain measurements using this technique, and discusses their recognized and developing clinical applications.

Effects of simvastatin on walking performance and symptoms of intermittent claudication in hypercholesterolemic patients with peripheral vascular disease

Abstract Purpose To analyze the effects of short-term therapy with simvastatin on walking performance in hypercholesterolemic patients with peripheral vascular disease. Methods Eighty-six patients with peripheral arterial disease (Fontaine stage II), intermittent claudication, and total cholesterol levels >220 mg/dL were enrolled in a randomized, placebo-controlled, double-blind study. Forty-three patients were assigned to simvastatin (40 mg/d); the remaining 43 patients were assigned to placebo treatment. All patients underwent an exercise test and clinical examination, and completed a self-assessment questionnaire at 0, 3, and 6 months. Pain-free and total walking distance, resting and postexercise ankle-brachial indexes, and questionnaire scores were determined at each follow-up. Results At 6 months, the mean pain-free walking distance had increased 90 meters (95% confidence interval [CI]: 64 to 116 meters; P P P P Conclusion High-dose short-term therapy with simvastatin may improve walking performance, ankle-brachial pressure indexes, and symptoms of claudication in hypercholesterolemic patients with peripheral vascular disease.

Feasibility and reference values of left atrial longitudinal strain imaging by two-dimensional speckle tracking

BackgroundThe role of speckle tracking in the assessment of left atrial (LA) deformation dynamics is not established. We sought to determine the feasibility and reference ranges of LA longitudinal strain indices measured by speckle tracking in a population of normal subjects.MethodsIn 60 healthy individuals, peak atrial longitudinal strain (PALS) and time to peak longitudinal strain (TPLS) were measured using a 12-segment model for the left atrium. Values were obtained by averaging all segments (global PALS and TPLS) and by separately averaging segments measured in the two apical views (4- and 2-chamber average PALS and TPLS).ResultsAdequate tracking quality was achieved in 97% of segments analyzed. Inter and intra-observer variability coefficients of measurements ranged between 2.9% and 5.4%. Global PALS was 42.2 ± 6.1% (5–95° percentile range 32.2–53.2%), and global TPLS was 368 ± 30 ms (5–95° percentile range 323–430 ms). The 2-chamber average PALS was slightly higher than the 4-chamber average PALS (44.3 ± 6.0% vs 40.1 ± 7.9%, p < 0.0001), whereas no differences in TPLS were found (p = 0.93).ConclusionSpeckle tracking is a feasible technique for the assessment of longitudinal myocardial LA deformation. Reference ranges of strain indices were reported.

Early Detection of Left Atrial Strain Abnormalities by Speckle-Tracking in Hypertensive and Diabetic Patients with Normal Left Atrial Size

BACKGROUND Systemic hypertension and type 2 diabetes mellitus are associated with impaired left atrial (LA) function, but whether LA functional abnormalities also occur in patients with hypertension and diabetes who have normal LA sizes is unknown. The aim of this study was to explore LA strain using speckle-tracking echocardiography in patients with hypertension or diabetes and normal LA size. METHODS LA strain was studied by speckle-tracking echocardiography in 155 patients with hypertension or diabetes with LA volume indexes < 28 mL/m(2) (83 with hypertension, 34 with diabetes, and 38 with both diabetes and hypertension) and 36 age-matched controls. The following indexes were measured: peak atrial longitudinal strain, time to peak atrial longitudinal strain, atrial longitudinal strain during early diastole and late diastole, and peak LA strain rate during ventricular systole, early diastole, and late diastole. RESULTS Peak atrial longitudinal strain was lower in patients with hypertension (29.0 ± 6.5%) and those with diabetes (24.7 ± 6.4%) than in controls (39.6 ± 7.8%) and further reduced in patients with diabetes and hypertension (18.3 ± 5.0%) (P < .0001). Similar results were found for atrial longitudinal strain during early diastole, atrial longitudinal strain during late diastole, and peak LA strain rate during ventricular systole and early diastole (P < .0001 for all). An inverse trend was found for time to peak atrial longitudinal strain, whereas no differences in peak LA strain rate during late diastole were observed. Two-way analysis of variance showed no interactions between hypertension and diabetes. In multivariate analyses, hypertension and diabetes were both independently associated with decreases in all LA strain and strain rate indexes, with the exception of peak LA strain rate during late diastole. CONCLUSIONS LA deformation mechanics are impaired in patients with hypertension or diabetes with normal LA size. The coexistence of both conditions further impairs LA performance in an additive fashion. Speckle-tracking echocardiography may be considered a promising tool for the early detection of LA strain abnormalities in these patients.

Left atrial longitudinal strain by speckle tracking echocardiography correlates well with left ventricular filling pressures in patients with heart failure

BackgroundThe combination of early transmitral inflow velocity and mitral annular tissue Doppler imaging (E/Em ratio) is widely applied to noninvasively estimate left ventricular (LV) filling pressures. However E/Em ratio has a significant gray zone and its accuracy in patients with heart failure is debated. Left atrial (LA) deformation analysis by speckle tracking echocardiography (STE) was recently proposed as an alternative approach to estimate LV filling pressures. This study aimed at exploring the correlation of LA longitudinal function by STE and Doppler measurements with direct measurements of LV filling pressures in patients with heart failure.MethodsA total of 36 patients with advanced systolic heart failure (ejection fraction ≤35%), undergoing right heart catheterization, were studied. Simultaneously to pulmonary capillary wedge pressure (PCWP) determination, peak atrial longitudinal strain (PALS) and mean E/Em ratio were measured in all subjects by two independent operators. PALS values were obtained by averaging all segments (global PALS), and by separately averaging segments measured in the 4-chamber and 2-chamber views.ResultsNot significant correlation was found between mean E/Em ratio and PCWP (R = 0.15). A close negative correlation between global PALS and the PCWP was found (R = -0.81, p < 0.0001). Furthermore, global PALS demonstrated the highest diagnostic accuracy (AUC of 0.93) and excellent sensitivity and specificity of 100% and 93%, respectively, to predict elevated filling pressure using a cutoff value less than 15.1%. Bland-Altman analysis confirmed this close agreement between PCWP estimated by global PALS and invasive PCWP (mean bias 0.1 ± 8.0 mmHg).ConclusionIn a group of patients with advanced systolic heart failure, E/Em ratio correlated poorly with invasively obtained LV filling pressures. However, LA longitudinal deformation analysis by STE correlated well with PCWP, providing a better estimation of LV filling pressures in this particular clinical setting.

Application of 2011 American College of Cardiology Foundation/American Society of Echocardiography Appropriateness Use Criteria in Hospitalized Patients Referred for Transthoracic Echocardiography in a Community Setting

BACKGROUND A recent American College of Cardiology Foundation and American Society of Echocardiography document updated previous appropriate use criteria (AUC) for echocardiography. The aim of this study was to explore the application of the new AUC, and the resulting appropriateness rate, in hospitalized patients referred for transthoracic echocardiography (TTE) in a community setting. METHODS A total of 931 consecutive inpatients referred for TTE were prospectively recruited in five community hospitals. Patients were categorized as having appropriate, uncertain, or inappropriate indications for TTE according to the AUC. An additional group of 259 inpatients, discharged without having been referred for TTE, was also considered. RESULTS In the group referred for TTE, the large majority of indications (98.8%) were classifiable according to the AUC with good interobserver reproducibility. Indications were appropriate in 739 patients (80.3%), of uncertain appropriateness in 46 (5.0%), and inappropriate in 135 (14.7%). Compared with patients with appropriate or uncertain indications, those with inappropriate indications were younger and more often referred by noncardiologists. Most common causes of inappropriate indications were related to the lack of changes in clinical status or to the absence of cardiovascular symptoms and signs. Examinations with appropriate or uncertain indications had an impact on clinical decision making more often than those with inappropriate indications (86.7% vs 14.1%, P < .0001). In the group discharged without having been referred for TTE, TTE might have been appropriate in 16.2% of cases. CONCLUSIONS Clinical application of the new AUC was highly feasible in a community setting. Although inpatient referral for TTE was appropriate in most patients, strategies aimed at implementing these criteria in clinical practice are desirable.

Echocardiography in patients with hypertrophic cardiomyopathy: usefulness of old and new techniques in the diagnosis and pathophysiological assessment

Hypertrophic cardiomyopathy (HCM) is one of the most common inherited cardiomyopathy. The identification of patients with HCM is sometimes still a challenge. Moreover, the pathophysiology of the disease is complex because of left ventricular hyper-contractile state, diastolic dysfunction, ischemia and obstruction which can be coexistent in the same patient. In this review, we discuss the current and emerging echocardiographic methodology that can help physicians in the correct diagnostic and pathophysiological assessment of patients with HCM.

Severity of aortic stenosis predicts early post-operative normalization of left atrial size and function detected by myocardial strain.

BACKGROUND Aortic stenosis (AS) causes significant disturbances in left ventricular (LV) and left atrial (LA) function irrespective of the extent of myocardial hypertrophy which associates the increased afterload. We hypothesize that aortic valve replacement (AVR) and removal of LV outflow tract obstruction should result in LA size and function recovery, even partial, and were set to study this in a group of patients with AVR for AS. METHODS Peak atrial longitudinal strain (PALS) was evaluated in 43 patients with severe isolated AS and normal EF (56.6 ± 3.8%) and no obstructive coronary artery disease candidates for AVR, pre-operatively and then 40 days and 3 months after surgery. Results were compared with those from 34 age- and gender-matched healthy controls. RESULTS LVEF remained unchanged and LV mass regressed after AVR. Global PALS was reduced pre-operatively and increased 40 days after surgery (p=0.002) and showed only a slight further increase at 3 months follow-up (p<0.0001). Indexed LA volume was increased before surgery, but significantly fell 40 days after surgery (p<0.0001) and showed only a slight further reduction after 3 months (p<0.0001). Trans-aortic mean gradient change after surgery was the only independent predictor of the recovery of LA size and function. CONCLUSIONS AVR reverses LA abnormalities and regains normal atrial function, a behavior which is directly related to the severity of pre-operative LV outflow tract obstruction. Early identification of LA size enlargement and functional disturbances might contribute to better patients recruitment for AVR.

Concordance between M-mode, pulsed Tissue Doppler, and colour Tissue Doppler in the assessment of mitral annulus systolic excursion in normal subjects.

AIMS M-mode left atrioventricular plane displacement (AVPD) correlates with Tissue Doppler (TD) peak systolic annular velocity in healthy individuals. This approach is biased by several interacting factors related to the structural complexity of mitral annulus physiology, including the different dimensional values of measures, the confounding effect of isovolumic motions, and the spectral thickness of pulsed TD envelope. We sought to analyze the effective concordance between techniques in the assessment of systolic annular excursion. METHODS AND RESULTS In 92 healthy subjects (age 60.5 +/- 18.6, 43.5% women), systolic AVPD was measured after exclusion of isovolumic components using three techniques: (i) M-mode; (ii) temporal integration of pulsed TD systolic wave; and (iii) colour TD-derived tissue tracking. Close correlations of M-mode AVPD with pulsed TD velocity-time integral (VTI) (R = 0.90, P < 0.0001) and colour TD AVPD (R = 0.86, P < 0.0001) were found. However, M-mode AVPD underestimated pulsed TD VTI (mean error -5.1 +/- 1.7 mm) and overestimated colour TD AVPD (mean error 3.4 +/- 1.3 mm). The concordance between M-mode and pulsed TD increased after adjustment for spectral dispersion of pulsed TD instantaneous velocities (mean error 0.1 +/- 1.1 mm). CONCLUSION Despite strict correlations exist between M-mode and TD in the assessment of mitral annulus systolic excursion, the effective concordance between techniques is sub-optimal.

Hypertension and acute myocardial infarction: an overview.

History of hypertension is a frequent finding in patients with acute myocardial infarction (AMI) and its recurring association with female sex, diabetes, older age, less frequent smoking and more frequent vascular comorbidities composes a risk profile quite distinctive from the normotensive ischemic counterpart.Antecedent hypertension associates with higher rates of death and morbid events both during the early and long-term course of AMI, particularly if complicated by left ventricular dysfunction and/or congestive heart failure. Renin-angiotensin-aldosterone system blockade, through either angiotensin-converting enzyme inhibition, angiotensin II receptor blockade or aldosterone antagonism, exerts particular benefits in that high-risk hypertensive subgroup.In contrast to the negative implications carried by antecedent hypertension, higher systolic pressure at the onset of chest pain associates with lower mortality within 1 year from coronary occlusion, whereas increased blood pressure recorded after hemodynamic stabilization from the acute ischemic event bears inconsistent relationships with recurring coronary events in the long-term follow-up.Whether antihypertensive treatment in post-AMI hypertensive patients prevents ischemic relapses is uncertain. As a matter of fact, excessive diastolic pressure drops may jeopardize coronary perfusion and predispose to new acute coronary events, although the precise cause-effect mechanisms underlying this phenomenon need further evaluation.