Elena Pasotti

Timing and Magnitude of Regional Right Ventricular Function: A Speckle Tracking-Derived Strain Study of Normal Subjects and Patients with Right Ventricular Dysfunction

BACKGROUND The aim of this study was to evaluate the timing and magnitude of global and regional right ventricular (RV) function by means of speckle tracking-derived strain in normal subjects and patients with RV dysfunction. METHODS Peak longitudinal systolic strain (PLSS) and time to PLSS in 6 RV segments (the basal, mid, and apical segments of the RV free wall and septum) were obtained in 100 healthy volunteers and 76 patients with RV dysfunction by tracking speckles inside the myocardium using grayscale images. Global PLSS and time to PLSS were based on the average of the 6 regional values. RESULTS There was a significant and close correlation between RV contractility as measured by PLSS and tricuspid annular plane systolic excursion (r = -0.83, P < .001). In normal subjects, PLSS was significantly greater in the free wall than in the septum (-28.7 + or - 4.1% vs -19.8 + or - 3.4%, P < .001), whereas time to PLSS was similar in the different regions of the right ventricle. In patients with RV dysfunction, global and regional PLSS was significantly less than in normal subjects (-13.7 + or - 3.6% vs -24.2 + or - 2.9%, P < .001), and a global PLSS cutoff value of -19% was helpful in distinguishing the two groups. Furthermore, time to PLSS in all of the RV septal segments and dispersion in RV contraction timing were significantly longer. Global PLSS in the patients with RV dysfunction was also significantly less in the presence of moderate to severe pulmonary hypertension (-12.7 + or - 3.6% vs -14.4 + or - 3.4%, P = .038). CONCLUSIONS Speckle tracking not only makes it possible to quantify global RV function but also illustrates the physiology of RV contraction and the pattern of activation at regional level. Speckle tracking-derived strain could become an important new means of assessing and following up patients with impaired RV function and increased pulmonary pressure.

Evaluation of the left atrial appendage with real-time 3-dimensional transesophageal echocardiography: implications for catheter-based left atrial appendage closure.

Background— Precise knowledge of left atrial appendage (LAA) orifice size is crucial for correct sizing of LAA closure devices. The aim of the present study was to determine the performance of real-time 3D transesophageal echocardiography (RT3DTEE) for LAA orifice size assessment, compared with 2D transesophageal echocardiography (2DTEE), and to investigate the impact of atrial fibrillation (AF) on LAA orifice size. Methods and Results— One hundred thirty-seven patients (38 control subjects, 31 with paroxysmal AF, 38 with persistent AF and 30 with permanent AF) underwent 2DTEE and RT3DTEE. Both techniques were used to measure LAA orifice area. Clinically-indicated 64-slice computed tomography (CT) was used as reference technique in 46 patients. Two-dimensional TEE underestimated LAA orifice area, compared with RT3DTEE (1.99±0.94 cm2 versus 3.05±1.27 cm2; P <0.001). RT3DTEE showed higher correlation with CT for the assessment of LAA orifice area, compared with 2DTEE ( r =0.92; 95% confidence interval, 0.85 to 0.95, versus r =0.72; 95% confidence interval, 0.54 to 0.83, respectively). At Bland–Altman analysis, RT3DTEE and 2DTEE underestimated LAA orifice area, compared with CT. However, RT3DTEE showed smaller bias (0.07 cm2 versus 0.72 cm2) and narrower limits of agreement (−0.71 to 0.85 cm2 versus −0.58 to 2.02 cm2) with CT, compared with 2DTEE. Among AF patients, a progressive increase in RT3DTEE-derived LAA orifice area was observed with increasing frequency of AF ( P <0.001). At multivariate analysis, AF and left atrial volume index ( P <0.001 for both) were independently associated with RT3DTEE-derived LAA orifice area. Conclusions— RT3DTEE is more accurate than 2DTEE for the assessment of LAA orifice size. A progressive increase in LAA orifice area is observed with increasing frequency of AF.Background— Precise knowledge of left atrial appendage (LAA) orifice size is crucial for correct sizing of LAA closure devices. The aim of the present study was to determine the performance of real-time 3D transesophageal echocardiography (RT3DTEE) for LAA orifice size assessment, compared with 2D transesophageal echocardiography (2DTEE), and to investigate the impact of atrial fibrillation (AF) on LAA orifice size. Methods and Results— One hundred thirty-seven patients (38 control subjects, 31 with paroxysmal AF, 38 with persistent AF and 30 with permanent AF) underwent 2DTEE and RT3DTEE. Both techniques were used to measure LAA orifice area. Clinically-indicated 64-slice computed tomography (CT) was used as reference technique in 46 patients. Two-dimensional TEE underestimated LAA orifice area, compared with RT3DTEE (1.99±0.94 cm2 versus 3.05±1.27 cm2; P<0.001). RT3DTEE showed higher correlation with CT for the assessment of LAA orifice area, compared with 2DTEE (r=0.92; 95% confidence interval, 0.85 to 0.95, versus r=0.72; 95% confidence interval, 0.54 to 0.83, respectively). At Bland–Altman analysis, RT3DTEE and 2DTEE underestimated LAA orifice area, compared with CT. However, RT3DTEE showed smaller bias (0.07 cm2 versus 0.72 cm2) and narrower limits of agreement (−0.71 to 0.85 cm2 versus −0.58 to 2.02 cm2) with CT, compared with 2DTEE. Among AF patients, a progressive increase in RT3DTEE-derived LAA orifice area was observed with increasing frequency of AF (P<0.001). At multivariate analysis, AF and left atrial volume index (P<0.001 for both) were independently associated with RT3DTEE-derived LAA orifice area. Conclusions— RT3DTEE is more accurate than 2DTEE for the assessment of LAA orifice size. A progressive increase in LAA orifice area is observed with increasing frequency of AF.

Predictors for efficacy of percutaneous mitral valve repair using the MitraClip system: the results of the MitraSwiss registry

Background Percutaneous mitral valve repair (MVR) using the MitraClip system has become a valid alternative for patients with severe mitral regurgitation (MR) and high operative risk. Objective To identify clinical and periprocedural factors that may have an impact on clinical outcome. Design Multi-centre longitudinal cohort study. Setting Tertiary referral centres. Patients Here we report on the first 100 consecutive patients treated with percutaneous MVR in Switzerland between March 2009 and April 2011. All of them had moderate–severe (3+) or severe (4+) MR, and 62% had functional MR. 82% of the patients were in New York Heart Association (NYHA) class III/IV, mean left ventricular ejection fraction was 48% and the median European System for Cardiac Operative Risk Evaluation was 16.9%. Interventions MitraClip implantation performed under echocardiographic and fluoroscopic guidance in general anaesthesia. Main outcome measures Clinical, echocardiographic and procedural data were prospectively collected. Results Acute procedural success (APS, defined as successful clip implantation with residual MR grade ≤2+) was achieved in 85% of patients. Overall survival at 6 and 12 months was 89.9% (95% CI 81.8 to 94.6) and 84.6% (95% CI 74.7 to 91.0), respectively. Univariate Cox regression analysis identified APS (p=0.0069) and discharge MR grade (p=0.03) as significant predictors of survival. Conclusions In our consecutive cohort of patients, APS was achieved in 85%. APS and residual discharge MR grade are important predictors of mid-term survival after percutaneous MVR.

The effect of the gastrointestinal lipase inhibitor, orlistat, on serum lipids and lipoproteins in patients with primary hyperlipidaemia

The effect of orlistat, a nonabsorbed inhibitor of gastric and pancreatic lipases, was examined in patients with primary hyperlipidaemia (serum cholesterol ≥6.2 mmol·l−1 and triglycerides ≤5.0 mmol·l−1) not responsive to dietary change alone. In a multicentre, randomised, double-blind study, 103 men and 70 women received 30, 90, 180, or 360 mg of orlistat or placebo for 8 weeks.Total and low-density lipoprotein cholesterol levels were reduced by 4% and 5% with 30 mg orlistat, by 7% and 8% with 90 mg orlistat, by 7% and 7% with 180 mg orlistat and by 11% and 10% with 360 mg orlistat compared to placebo. High density lipoprotein cholesterol levels significantly decreased in the 360 mg orlistat group. Triglyceride levels significantly increased in the placebo group but not in the drug groups. Body weight decreased by 1.2 kg with 360 mg orlistat, despite a weight maintenance diet. Decreases in vitamin E and D levels occurred, although both vitamins remained within the normal range.Adverse effects from the gastrointestinal tract were frequent, but led to discontinuation of therapy in only seven patients. Orlistat is a new therapeutic drug for the treatment of hyperlipidaemia that may be particularly useful among overweight patients. Its potential place in therapy will await long-term studies. Vitamin supplementation should be considered during treatment.

Comparison of Brain Natriuretic Peptide Plasma Levels Versus Logistic EuroSCORE in Predicting In-Hospital and Late Postoperative Mortality in Patients Undergoing Aortic Valve Replacement for Symptomatic Aortic Stenosis

The accuracy of the logistic EuroSCORE (logES), a widely used risk prediction algorithm for cardiac surgery including aortic valve surgery, usually overestimates observed perioperative mortality. Elevated brain natriuretic peptide (BNP) in symptomatic patients with aortic stenosis (AS) is associated with a poor short-term outcome after aortic valve replacement. We aimed to compare BNP with the logES for predicting short- and long-term outcome in symptomatic patients with severe AS undergoing aortic valve replacement. We prospectively studied 144 consecutive patients referred for aortic valve replacement (42% women, 73 +/- 9 years, mean aortic gradient 51 +/- 18 mm Hg, and left ventricular ejection fraction 61 +/- 11%) undergoing either isolated aortic valve replacement (58%) or combined to bypass grafting. Both plasma BNP and logES was estimated before surgery. The median BNP plasma level and logES were 157 pg/ml (interquartile range [IQR] 61 to 440) and 6.6% (IQR 4.2 to 12.2), respectively. The perioperative mortality was 6% and the overall mortality by the end of the study was 13%. Patients with logES >10.1% (upper tertile) had a higher risk of dying over time (hazard ratio [HR] 2.86, p = 0.037), as had patients with BNP >312 pg/ml (HR 9.01, p <0.001). Discrimination (based on C statistic) and model performance (based on Akaike information criterion) were better for BNP than for logES. At the bivariable analysis, only BNP was an independent predictor of death (HR 8.2, p = 0.002). Preoperative BNP was even more accurate than logES in predicting outcome. In conclusion, in symptomatic patients with severe AS, high preoperative BNP plasma level and high logES confirm their predicting value for short- and long-term outcome.

Echocardiographic Parameters of Mechanical Synchrony in Healthy Individuals

Definition and validation of the ranges of normal values and agreement among echocardiographic measures of mechanical synchrony in healthy subjects are mostly lacking. The aims of this study were (1) to assess the ranges of normal values for 5 tissue Doppler imaging parameters, real-time 3-dimensional echocardiographic measures, and speckle-tracking measures of mechanical synchrony; (2) to evaluate interinstitutional variability; (3) to compare the ranges of normal values with those reported in previous research; and (4) to analyze the agreement among all parameters in the same healthy subject. Time to peak systolic velocity (Ts), the delay between Ts at the basal septal and lateral segments, peak velocity difference, strain derived by tissue Doppler imaging, Ts derived by tissue synchronization imaging, systolic synchrony index (SSI) derived by real-time 3-dimensional echocardiography, and longitudinal and radial strain derived by speckle tracking were prospectively collected and analyzed at 2 different institutions in 160 consecutive healthy subjects. The ranges of normal values, expressed as means +/- 2 SDs, were 30.32 +/- 29.36 ms for the SD of Ts, 15.51 +/- 99.88 ms for septal-lateral delay, 60.75 +/- 81.62 ms for peak velocity difference, 33.07 +/- 29.96 ms for tissue synchronization imaging, 34.16 +/- 23.26 ms for the SD of strain, 2.74 +/- 2.16% for SSI, 28.91 +/- 23.02 ms for the SD of longitudinal strain, and 10.4 +/- 6.31 ms for radial strain. There was large interinstitutional variability for all parameters. Three-dimensional SSI and radial strain were within the published upper range limit for healthy subjects. Ninety percent of healthy subjects were consistently classified to be synchronous by 1 parameter. With a composite index, more subjects than expected showed dyssynchrony (10% vs 2.5%). In conclusion, 3-dimensional SSI and radial strain were the most reproducible parameters and consistently discriminated normal healthy subjects from the cardiac resynchronization therapy volume responders.

Estimates of lifetime attributable risk of cancer after a single radiation exposure from 64-slice computed tomographic coronary angiography

Aims To estimate the life attributable risk (LAR) of cancer incidence over a wide range of dose radiation exposure and a large spectrum of possible diagnostic computed tomographic coronary angiography (CTCA) scenarios. Methods This study included 561 consecutive patients who underwent a successful prospective ECG-gating CTCA protocol (low-dose group) 64-slice CTCA and 188 patients who underwent retrospective ECG-gating CTCA with ECG-triggered dose modulation CTCA (high-dose group). LAR was computed, given the organ equivalent dose, for all cancers in both sexes. LAR was tabulated for each decile of dose-length product by 10-year age classes, separately for each sex. Results Estimates of LAR of any cancer for an exposure at age ≤40 year were lower in males than in females for any given quantile. At age ≥50years, LAR was similar between sexes only at the lowest exposure doses, whereas at higher dosage, it was, in general, higher for women. At the median age of this case series (62 years) and for a radiation exposure ranging from 1.33 to 3.81 mSv, LAR was 1 in 4329 (or 23.1 per 105 persons exposed) and 1 in 4629 (or 21.6 per 105 persons) in men and women, respectively. For an exposure ranging from 10.34 to 18.97 mSv at the same median age, the LAR of cancer incidence was 1 in 1336 (or 74.8 per 105 persons) in men and doubled (1 in 614 or 162.8 per 105 persons) in women. Conclusions This study provided an estimate of the LAR of cancer in middle-aged patients of both sexes after a single diagnostic CTCA, providing an easy-to-read table.

3D TEE during catheter-based interventions.

Guidance of catheter-based procedures is performed using fluoroscopy and 2-dimensional transesophageal echocardiography (TEE). Both of these imaging modalities have significant limitations. Because of its 3-dimensional (3D) nature, 3D TEE allows visualizing the entire scenario in which catheter-based procedures take place (including long segments of catheters, tips, and the devices) in a single 3D view. Despite these undeniable advantages, 3D TEE has not yet gained wide acceptance among most interventional cardiologists and echocardiographists. One reason for this reluctance is probably the absence of standardized approaches for obtaining 3D perspectives that provide the most comprehensive information for any single step of any specific procedure. Therefore, the purpose of this review is to describe what we believe to be the most useful 3D perspectives in the following catheter-based percutaneous interventions: transseptal puncture; patent foramen ovale/atrial septal defect closure; left atrial appendage occlusion; mitral valve repair; and closure of paravalvular leaks.

Comparison of Eight Echocardiographic Methods for Determining the Prevalence of Mechanical Dyssynchrony and Site of Latest Mechanical Contraction in Patients Scheduled for Cardiac Resynchronization Therapy

Prevalence of echocardiographically assessed mechanical dyssynchrony and consistency in detection of the latest mechanical left ventricular (LV) contracting region when different echocardiographic methods are used in the same patient remains ill-defined. The objectives of this study were to evaluate (1) the prevalence of intraventricular mechanical dyssynchrony and (2) consistency of latest mechanical LV contraction using a multiparametric approach derived from tissue Doppler imaging (TDI), 3-dimensional (3D) echocardiography, and speckle tracking in patients scheduled for cardiac resynchronization therapy (CRT). In 63 patients with heart failure scheduled for CRT, 2D echocardiography, TDI, 3D echocardiography, and speckle tracking were prospectively collected and analyzed. Prevalence of dyssynchrony was low for some tissue-velocity derived indexes (11%, 13%, and 43%) but was >or=80% for strain derived by TDI, for systolic dyssynchrony index by 3D echocardiography, and for longitudinal and radial strains by speckle tracking. Prevalence of dyssynchrony was 69% for maximum delay between anteroseptal and posterolateral walls by radial strain. Agreement among dyssynchrony indexes was generally low (kappa -0.02). Agreement of each of these echocardiographic indexes in determining, in the same patient with heart failure, the latest LV mechanical contraction site was also low (no site agreement in 77%). In conclusion, in a typical CRT population there is considerable variability among various techniques that assess prevalence of mechanical dyssynchrony and in identification of the latest mechanical LV contracting region.

Redistribution of left ventricular strain by cardiac resynchronization therapy in heart failure patients.

The aim of this study was to investigate (i) the baseline patterns of segmental peak myocardial strain (PMS) in heart failure (HF) patients with ventricular conduction delay, (ii) changes in patterns of segmental PMS induced by cardiac resynchronization therapy (CRT), and (iii) whether they differ between CRT responders and non‐responders.