Effect of noradrenaline on an early and a late component of the myocardial contraction

1978 ◽  
Vol 305 (1) ◽  
pp. 65-74 ◽  
Author(s):  
K. Seibel ◽  
E. Karema ◽  
K. Takeya ◽  
M. Reiter
2006 ◽  
Vol 5 (1) ◽  
pp. 46-46
Author(s):  
N ARTIS ◽  
D OXBOROUGH ◽  
G WILLIAMS ◽  
L TAN ◽  
C PEPPER

2001 ◽  
Vol 8 (1) ◽  
pp. S100-S100
Author(s):  
N KOBAYASHI ◽  
H YAMABE ◽  
H TAKETOU ◽  
K SAKURAI ◽  
S FUJIWARA

1995 ◽  
Vol 268 (1) ◽  
pp. H178-H183 ◽  
Author(s):  
U. Mehlhorn ◽  
K. L. Davis ◽  
E. J. Burke ◽  
D. Adams ◽  
G. A. Laine ◽  
...  

Cardioplegic arrest (CPA) is associated with interstitial myocardial edema, which has been shown to impair myocardial function. The accumulation of interstitial myocardial edema may be enhanced by impaired myocardial lymph flow. The purpose of this study was to investigate the effects of CPA on myocardial lymphatic function. In nine anesthetized dogs, we cannulated a prenodal cardiac lymphatic and measured myocardial lymph flow rate (QL), myocardial lymph driving pressure (PL), and myocardial lymph hyaluronan (Hya) concentration. We determined left ventricular function using pressure-volume curves derived by sonomicrometry and micromanometry. The dogs were placed on cardiopulmonary bypass (CPB) (28 degrees C) and subjected to 60 min of hypothermic, crystalloid CPA. With the onset of asystole both QL and PL decreased significantly from 70.7 +/- 31.8 (SD) to 3.3 +/- 4.0 microliters/min and from 19.9 +/- 8.0 to 10.4 +/- 1.8 mmHg, respectively (P < 0.01). Following return of sinus rhythm after separation from CPB, QL and PL increased significantly to 135.4 +/- 28.0 microliters/min and 27.3 +/- 7.5 mmHg, respectively (P < 0.01). Post-CPA myocardial edema was demonstrated by gravimetric wet-to-dry weight determination of 3.67 +/- 0.20 (normal 2.90 +/- 0.20, P < 0.001) and was associated with significantly decreased left ventricular function. Myocardial Hya turnover rate was 1.3 +/- 1.0% per day under baseline conditions and increased significantly to 2.7 +/- 0.9% per day post-CPA (P < 0.01). We conclude that organized myocardial contraction is the major determinant of myocardial lymph flow. Myocardial lymph flow impairment during CPA may contribute to post-CPA myocardial edema and left ventricular dysfunction.


2020 ◽  
Vol 169 (6) ◽  
pp. 787-790
Author(s):  
A. А. Zverev ◽  
N. V. Leonov ◽  
Т. А. Аnikina ◽  
Т. L. Zefirov

Circulation ◽  
2008 ◽  
Vol 118 (suppl_18) ◽  
Author(s):  
Jun Tanaka ◽  
Satoshi Nakatani ◽  
Makoto Amaki ◽  
Hideaki Kanzaki ◽  
Shuji Hashimoto ◽  
...  

Dilated cardiomyopathy (DCM) is histologically characterized by myocardial fibrosis and cellular hypertrophy. These myocardial changes may affect timing of regional peak contraction. We investigated whether there was a correlation between intraventricular septal (IVS) intramural asynchrony based on tissue velocity imaging and the histologic changes. We obtained apical 4-chamber tissue velocity images in 27 normal subjects and 22 patients with DCM undergoing myocardial biopsy using Vivid 7 (GE). We set 6 tandem regions of interest (ROIs) on the mid level of the IVS and measured the time to peak myocardial contraction (Ts) from the QRS onset at each ROI. We defined the standard deviation of Ts (Ts-SD) as an index of IVS asynchrony. Further, we analyzed a correlation between Ts-SD and the degree of myocardial fibrosis and cellular hypertrophy. The degree of myocardial fibrosis and cellular hypertrophy was graded qualitatively (0 to 3 scale) according to the percent of fibrosis occupied of the tissue sample and cell size. Ts-SD was larger in patients with DCM compared with normal subjects (13.9±12.3 vs. 6.2±4.0 ms, p<0.05), suggesting asynchronous contraction of IVS in DCM. Ts-SD showed a significant correlation with the degree of myocardial fibrosis (grade 1, 6.9±3.5 ms; grade 2, 15.7±3.5 ms; grade 3, 25.9±5.3 ms; p<0.05), while not with that of cellular hypertrophy (p=0.50). There was intramural asynchrony in IVS in DCM. This method could predict the degree of myocardial fibrosis noninvasively. Because myocardial fibrosis is the substrate for heart failure in DCM, the present method should provide clinically important information.


2018 ◽  
Vol 5 (3) ◽  
pp. 41 ◽  
Author(s):  
Vicente Mora ◽  
Ildefonso Roldán ◽  
Elena Romero ◽  
Assumpció Saurí ◽  
Diana Romero ◽  
...  

Background: According to the ventricular myocardial band model, the diastolic isovolumetric period is a contraction phenomenon. Our objective was to employ speckle-tracking echocardiography (STE) to analyze myocardial deformation of the left ventricle (LV) and to confirm if it supports the myocardial band model. Methods: This was a prospective observational study in which 90 healthy volunteers were recruited. We evaluated different types of postsystolic shortening (PSS) from an LV longitudinal strain study. Duration of latest deformation (LD) was calculated as the time from the start of the QRS complex of the ECG to the latest longitudinal deformation peak in the 18 segments of the LV. Results: The mean age of our subjects was 50.3 ± 11.1 years. PSS was observed in 48.4% of the 1620 LV segments studied (19.8%, 13.5%, and 15.1% in the basal, medial, and apical regions, respectively). PSS was more frequent in the basal, medial septal, and apical anteroseptal segments (>50%). LD peaked in the interventricular septum and in the basal segments of the LV. Conclusions: The pattern of PSS and LD revealed by STE suggests there is contraction in the postsystolic phase of the cardiac cycle. The anatomical location of the segments in which this contraction is most frequently observed corresponds to the main path of the ascending component of the myocardial band. This contraction can be attributed to the protodiastolic untwisting of the LV.


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