[Show abstract][Hide abstract] ABSTRACT: To analyze left ventricular (LV) obstruction in hypertrophic cardiomyopathy (HCM) during exercise echocardiography.
Despite the association of symptoms with LV outflow tract obstruction in HCM, there exist paradoxical situations in which significant intraventricular gradients (>50 mmHg) at rest occur in conjunction with excellent exercise tolerance.
To examine this phenomenon we performed exercise echocardiography and analyzed the clinical status in 107 HCM patients with and without resting obstruction.
At rest, 69 patients had no obstruction while 38 exhibited an intraventricular gradient, 9 of whom exhibited a decrease in gradient of at least 30 mmHg (99±35 to 30±14 mmHg, p<0.001) during exercise (paradoxical response to exercise or PRE). PRE patients presented a significantly lower NYHA clinical class and higher left ventricular volumes and arterial pressure both at rest and during exercise than HCM patients in whom the gradient increased or did not change during stress echocardiography. Finally, PRE patients exhibited a trend toward a reduced rate of cardiac events.
Our study reports a subgroup of HCM patients, designated PRE, based on a decreased intraventricular gradient during exercise. The reduced exertional obstruction may account for the better functional class and trend to less clinical events in PRE patients.
Journal of the American College of Cardiology 06/2013; 62(9). DOI:10.1016/j.jacc.2013.06.007 · 16.50 Impact Factor
[Show abstract][Hide abstract] ABSTRACT: The aim of this study was to evaluate the capacity and reproducibility of three-dimensional echocardiographic (3DE) strain parameters in the assessment of global left ventricular (LV) systolic function.
A total of 128 subjects with differing LV ejection fractions were investigated using two-dimensional echocardiographic (2DE) and 3DE strains. Three-dimensional echocardiographic strain allows obtaining longitudinal, circumferential, radial, and area strains. First, values of global longitudinal strain (GLS) by 2DE and 3DE speckle-tracking analyses were compared. Thereafter, 3DE strain parameters were correlated with LV ejection fraction and indexed output. Last, the variability of 3DE versus 2DE strain measurements as well as recorded time of analysis were assessed.
After excluding 21 patients for insufficient image quality, four for arrhythmia, two for severe valvular disease, and one for severe dyspnea, the final population consisted of 100 patients. Comparison between 2DE and 3DE GLS revealed high correspondence (r = 0.91, y = 1.04x - 0.71) and mean error measurement of -1.3% (95% confidence interval, -5.7 to 3.2). Among strain parameters, global area strain exhibited the highest correlation with LV ejection fraction (y = -1.65 + 10.4, r = -0.92, P < .001). Intraobserver measurement variability proved acceptable: 8% for GLS (vs 6% on 2DE analysis), 7% for circumferential strain (vs 15% on 2DE analysis), 7% for radial strain (vs 33% on 2DE analysis), and 5% for global area strain. The mean error between two measurements was lower with 3DE than 2DE analysis for circumferential and radial strains but similar for GLS. The mean time of analysis was of 117 ± 16 sec for 3DE analysis, which was 25% less than for 2DE analysis (P < .001).
Of all strain parameters, new 3DE area strain correlated best with common LV systolic function parameters and is thus the most promising approach, while all 3DE strain markers exhibited good reproducibility.
Journal of the American Society of Echocardiography: official publication of the American Society of Echocardiography 11/2011; 25(1):68-79. DOI:10.1016/j.echo.2011.10.009 · 4.06 Impact Factor
[Show abstract][Hide abstract] ABSTRACT: We evaluated the ability of a new simplified algorithm for three-dimensional echocardiography (3DE) left ventricular (LV) measurements with minimal operator interaction to be reproducible and robust, independently of the experience.
A total of 163 subjects were investigated using two-dimensional echocardiography (2DE) and 3DE. The 3D data sets were blindly analysed offline by novice investigators and experts. A subgroup of 30 patients was assessed using cardiac magnetic resonance imaging (CMRI) to compare end-diastolic volume (EDV), end-systolic volume (ESV), and ejection fraction (EF) obtained by 2DE, 3DE, and CMRI. Intra-observer and inter-observer variabilities of 2DE and 3DE measurements were evaluated according to level of experience. Mean time analysis of 3DE data was 23.2 ± 6.3s for the novice and 26.1 ± 4.1 s for the expert (P = ns). Correlations (r) and mean error measurements (MEM) between 3DE analysis by experts and novices were 0.91 and -3.5 mL for EDV, 0.97 and 4.3 mL for ESV, and 0.91 and -2.6% for EF, respectively. Correlations between 3DE and CMRI were good with low variability and greater agreement when compared with those between 2DE and CMRI. For the novice, MEM was -21.3 mL for EDV, -15.0 mL for ESV, and 2.3% for EF. MEM and 95% confidence intervals were wider for 2DE vs. CMRI than for 3DE vs. CMRI in relation to both expert and novice.
This new semi-automated algorithm of LV endocardial border detection based on 3DE data appears suitable for clinical use by either expert or novice investigators with greater reproducibility and time of analysis than 2DE.