Cardiac incoordination induced by left bundle branch block: its relation with left ventricular systolic function in patients with and without cardiomyopathy

<p>Abstract</p> <p>Background</p> <p>Although left bundle branch block (LBBB) alters the electrical activation of the heart, it is unknown how it might change the process of myocardial coordination (MC) and how it may affect the left ventricular (LV) systolic function. The present study assessed the effects of LBBB on MC in patients with LBBB with and without dilated (DCMP) or ischemic cardiomyopathy (ICMP).</p> <p>Methods</p> <p>Tissue Doppler echocardiography (TDE) was performed in 86 individuals: 21 with isolated LBBB, 26 patients with DCMP + LBBB, 19 patients with ICMP + LBBB and in 20 healthy individuals (Controls). MC was assessed analyzing the myocardial velocity profiles obtained from six basal segments of the LV using TDE. The LV systolic function was assessed by standard two-dimensional echocardiography and by TDE.</p> <p>Results</p> <p>Severe alterations in MC were observed in subjects with LBBB as compared with controls (P < 0.01 for all comparisons); these derangements were even worse in patients with DCMP and ICMP (P < 0.001 for comparisons with Controls and P < 0.01 for comparison with individuals with isolated LBBB). Some parameters of MC differed significantly between DCMP and ICMP (P < 0.01). A good or very good correlation coefficient was found between variables of MC and variables of LV systolic function.</p> <p>Conclusion</p> <p>LBBB induces severe derangement in the process of MC that are more pronounced in patients with cardiomyopathies and that significantly correlates with the LV systolic function. The assessment of MC may help in the evaluation of the etiology of dilated cardiomyopathy.</p

Tissue Doppler Imaging can be useful to distinguish pathological from physiological left ventricular hypertrophy: a study in master athletes and mild hypertensive subjects

<p>Abstract</p> <p>Background</p> <p>Transthoracic echocardiography left ventricular wall thickness is often increased in master athletes and it results by intense physical training. Left Ventricular Hypertrophy can also be due to a constant pressure overload. Conventional Pulsed Wave (PW) Doppler analysis of diastolic function sometimes fails to distinguish physiological from pathological LVH.</p> <p>The aim of this study is to evaluate the role of Pulsed Wave Tissue Doppler Imaging in differentiating pathological from physiological LVH in the middle-aged population.</p> <p>Methods</p> <p>we selected a group of 80 master athletes, a group of 80 sedentary subjects with essential hypertension and an apparent normal diastolic function at standard PW Doppler analysis. The two groups were comparable for increased left ventricular wall thickness and mass index (134.4 ± 19.7 vs 134.5 ± 22.1 gr/m2; p > .05). Diastolic function indexes using the PW technique were in the normal range for both.</p> <p>Results</p> <p>Pulsed Wave TDI study of diastolic function immediately distinguished the two groups. While in master athletes the diastolic TDI-derived parameters remained within normal range (E' 9.4 ± 3.1 cm/sec; E/E' 7.8 ± 2.1), in the hypertensive group these parameters were found to be constantly altered, with mean values and variation ranges always outside normal validated limits (E' 7.2 ± 2.4 cm/sec; E/E' 10.6 ± 3.2), and with E' and E/E' statistically different in the two groups (p < .001).</p> <p>Conclusion</p> <p>Our study showed that the TDI technique can be an easy and validated method to assess diastolic function in differentiating normal from pseudonormal diastolic patterns and it can distinguish physiological from pathological LVH emphasizing the eligibility certification required by legal medical legislation as in Italy.</p

Assessment of atrial regional and global electromechanical function by tissue velocity echocardiography: a feasibility study on healthy individuals

BACKGROUND: The appropriate evaluation of atrial electrical function is only possible by means of invasive electrophysiology techniques, which are expensive and therefore not suitable for widespread use. Mechanical atrial function is mainly determined from atrial volumes and volume-derived indices that are load-dependent, time-consuming and difficult to reproduce because they are observer-dependent. AIMS: To assess the feasibility of tissue velocity echocardiography (TVE) to evaluate atrial electromechanical function in young, healthy volunteers. SUBJECTS AND METHODS: We studied 37 healthy individuals: 28 men and nine women with a mean age of 29 years (range 20–47). Standard two-dimensional (2-D) and Doppler echocardiograms with superimposed TVE images were performed. Standard echocardiographic images were digitized during three consecutive cardiac cycles in cine-loop format for off-line analysis. Several indices of regional atrial electrical and mechanical function were derived from both 2-D and TVE modalities. RESULTS: Some TVE-derived variables indirectly reflected the atrial electrical activation that follows the known activation process as revealed by invasive electrophysiology. Regionally, the atrium shows an upward movement of its walls at the region near the atrio-ventricular ring with a reduction of this movement towards the upper levels of the atrial walls. The atrial mechanical function as assessed by several TVE-derived indices was quite similar in all left atrium (LA) walls. However, all such indices were higher in the right (RA) than the LA. There were no correlations between the 2-D- and TVE-derived variables expressing atrial mechanical function. Values of measurement error and repeatability were good for atrial mechanical function, but only acceptable for atrial electrical function. CONCLUSION: TVE may provide a simple, easy to obtain, reproducible, repeatable and potentially clinically useful tool for quantifying atrial electromechanical function

Live-cell 3D super-resolution imaging in thick biological samples

We demonstrate three-dimensional (3D) super-resolution live-cell imaging through thick specimens (50-150 \u3bcm), by coupling far-field individual molecule localization with selective plane illumination microscopy (SPIM). The improved signal-to-noise ratio of selective plane illumination allows nanometric localization of single molecules in thick scattering specimens without activating or exciting molecules outside the focal plane. We report 3D super-resolution imaging of cellular spheroids

New universal definition of myocardial infarction applicable after complex percutaneous coronary interventions?

OBJECTIVES: This study aimed to characterize myocardial infarction after percutaneous coronary intervention (PCI) based on cardiac marker elevation as recommended by the new universal definition and on the detection of late gadolinium enhancement (LGE) by cardiovascular magnetic resonance (CMR). It is also assessed whether baseline inflammatory biomarkers are higher in patients developing myocardial injury. BACKGROUND: Cardiovascular magnetic resonance accurately assesses infarct size. Baseline C-reactive protein (CRP) and neopterin predict prognosis after stent implantation. METHODS: Consecutive patients with baseline troponin (Tn) I within normal limits and no LGE in the target vessel underwent baseline and post-PCI CMR. The Tn-I was measured until 24 h after PCI. Serum high-sensitivity CRP and neopterin were assessed before coronary angiography. RESULTS: Of 45 patients, 64 (53 to 72) years of age, 33% developed LGE with infarct size of 0.83 g (interquartile range: 0.32 to 1.30 g). A Tn-I elevation &gt;99% upper reference limit (i.e., myocardial necrosis) (median Tn-I: 0.51 μg/l, interquartile range: 0.16 to 1.23) and Tn-I &gt; 3× upper reference limit (i.e., type 4a myocardial infarction [MI]) occurred in 58% and 47% patients, respectively. LGE was undetectable in 42% and 43% of patients with periprocedural myocardial necrosis and type 4a MI, respectively. Agreement between LGE and type 4a MI was moderate (kappa = 0.45). The levels of CRP or neopterin did not significantly differ between patients with or without myocardial injury, detected by CMR or according to the new definition (p = NS). CONCLUSIONS: This study reports the lack of substantial agreement between the new universal definition and CMR for the diagnosis of small-size periprocedural myocardial damage after complex PCI. Baseline levels of CRP or neopterin were not predictive for the development of periprocedural myocardial damage