Altered coronary and cardiac adrenergic response in the failing hamster heart: role of cyclooxygenase derivatives

2002 ◽  
Vol 80 (3) ◽  
pp. 218-225 ◽  
Author(s):  
Danica Brousseau ◽  
Jean-François Desjardins ◽  
Gaëtan Jasmin ◽  
Louis Dumont
Keyword(s):  
Heart Failure ◽  
Coronary Flow ◽  
Cardiac Response ◽  
Adrenergic System ◽  
Inotropic Response ◽  
Adrenergic Stimulation ◽  
Isolated Hearts ◽  
Cardiac Dynamics ◽  
Before And After ◽  
Hamster Heart

Although the influence of the adrenergic system has been studied in the presence of heart failure, controversies still exist. Since cyclooxygenase derivatives appear to modulate coronary and cardiac adaptation in the failing heart, we hypothesized that cyclooxygenase derivatives may participate in the altered adrenergic responses in this situation. Isolated hearts from cardiomyopathic (UM-X7.1 subline) and normal hamsters, aged >240 days, were utilized. Coronary and cardiac response to α1-, β1-, and β2-adrenergic stimulations was observed before and after pretreatment with indomethacin, a cyclooxygenase inhibitor. Reduction of coronary flow elicited by α1-adrenergic stimulation was unchanged in the presence of heart failure, while β1- and β2-induced vasodilatations were reduced. Inotropic response to α1 and β1 stimulations were also reduced in failing hearts, while β2-adrenergic action was unchanged. Pretreatment with indomethacin exacerbated coronary flow reduction observed with α1 stimulation in failing hearts only. β2-induced coronary vasodilatation and inotropic response to α1 and β2 stimulations were impaired similarly in the presence of indomethacin in normal and failing hearts. The results suggest a complex interaction between adrenergic and cyclooxygenase activation.Key words: adrenergic, cyclooxygenase, heart failure, coronary flow, cardiac dynamics.

scholarly journals Adrenergic stimulation promotes T-wave alternans and arrhythmia inducibility in a TNF-α genetic mouse model of congestive heart failure

2010 ◽  
Vol 298 (2) ◽  
pp. H440-H450 ◽  
Author(s):  
Vladimir Shusterman ◽  
Charles F. McTiernan ◽  
Anna Goldberg ◽  
Samir Saba ◽  
Guy Salama ◽  
...  
Keyword(s):  
Heart Failure ◽  
Congestive Heart Failure ◽  
Mean Amplitude ◽  
Adrenergic Stimulation ◽  
T Wave ◽  
Electrophysiological Testing ◽  
Tnf Α ◽  
Before And After ◽  
The Mean ◽  
T Wave Alternans

T-wave alternans (TWA) is a proarrhythmic repolarization instability that is common in congestive heart failure (CHF). Although transgenic mice are commonly used to study the mechanisms of arrhythmogenesis in CHF, little is known about the dynamics of TWA in these species. We hypothesized that TWA is present in a TNF-α model of CHF and can be further promoted by adrenergic stimulation. We studied 16 TNF-α mice and 12 FVB controls using 1) in vivo intracardiac electrophysiological testing and 2) ambulatory telemetry during 30 min before and after an intraperitoneal injection of isoproterenol. TWA was examined using both linear and nonlinear filtering applied in the time domain. In addition, changes in the mean amplitude of the T wave and area under the T wave were computed. During intracardiac electrophysiological testing, none of the animals had TWA or inducible arrhythmias before the injection of isoproterenol. After the injection, sustained TWA and inducible ventricular tachyarrhythmias were observed in TNF-α mice but not in FVB mice. In ambulatory telemetry, before the isoproterenol injection, the cardiac cycle length (CL) was longer in TNF-α mice than in FVB mice (98 ± 9 and 88 ± 3 ms, P = 0.04). After the injection of isoproterenol, the CL became 8% and 6% shorter in TNF-α and FVB mice ( P < 10−4); however, the 2% difference between the groups in the magnitude of CL changes was not significant. In TNF-α mice, the magnitude of TWA was 1.5–2 times greater than in FVB mice both before and after the isoproterenol injection. The magnitude of TWA increased significantly after the isoproterenol injection compared with the baseline in TNF-α mice ( P = 0.003) but not in FVB mice. The mean amplitude of the T wave and area under the T wave increased 60% and 80% in FVB mice ( P = 0.006 and 0.009) but not in TNF-α mice. In conclusion, TWA is present in a TNF-α model of CHF and can be further promoted by adrenergic stimulation, along with the enhanced susceptibility for ventricular arrhythmias.

Intraoperative transesophageal assessment of coronary artery flow can predict 5 type myocardial infarction

2020 ◽  
Vol 41 (Supplement_2) ◽  
Author(s):  
A Zagatina ◽  
M Novikov ◽  
N Zhuravskaya ◽  
V Balakhonov ◽  
S Efremov ◽  
...  
Keyword(s):  
Myocardial Infarction ◽  
Cardiac Surgery ◽  
Coronary Artery ◽  
Flow Velocity ◽  
Coronary Flow ◽  
Index Number ◽  
Left Main ◽  
Coronary Flow Velocity ◽  
Before And After ◽  
Flow Velocities

Abstract Background Stenosis of a coronary artery results in an increase in flow velocity in the pathologic segment. Effective grafting should decrease the stenotic native coronary velocity according to hemodynamic law. The range of decreased velocity before and after cardiac surgery can hypothetically reflect the effectiveness of a graft. The aim of the study is to determine if measuring coronary flow velocity changes during coronary artery bypass grafting (CABG) can predict intraoperative myocardial infarction. Methods One hundred sixty-six (166) consecutive patients (121 men, 64±9 years old) referred for cardiac surgery, were prospectively included in the study. A standard basic perioperative transesophageal echocardiography (TEE) examination was performed with additional scans of the left main, left anterior descending (LAD), and circumflex (LCx) arteries' proximal segments. Measurements of coronary flow velocities were performed before and after grafting in the same sites of the arteries. The maximal value of cardiac troponin I (cTnI) after CABG and the additive criteria were accounted for in the analysis as it is described in the expert consensus document for Type 5 myocardial infarction (MI) definition. Results One hundred sixty-three patients (98%) had arterial hypertension, 28 patients (17%) had diabetes mellitus, 35 patients (21%) were currently smokers. The feasibility of coronary flow assessment during cardiac operations was 95%. Before grafting, the mean velocity in the left main artery was 91±49 cm/s, in LAD 101±35 cm/s, and in LCx 117±49 cm/s. There was a significant correlation between changes in coronary flow velocities during operation and the value of cTnI (R=0.34, p&lt;0.0001). Ten patients met the criteria for Type 5 MI. There were no differences in age, body mass index, number of coronary arteries with stenoses, frequency of prior MI, ejection fraction or coronary flow velocity before surgery in patients with and without Type 5 MI. The group of patients with Type 5 MI had an increase in native artery velocities during surgery in comparison with patients without MI, who had a significant decrease in coronary flow velocity after grafting (30±48 vs. −10±30 cm/s; p&lt;0.0006). Increases in native coronary velocities greater than 3 cm/s predicted Type 5 MI with 81% accuracy (sensitivity 88%, specificity 70%). Conclusion Coronary flow velocity assessment during cardiac surgery could predict an elevation of cardiac troponins and Type 5 MI. Funding Acknowledgement Type of funding source: None

scholarly journals Effects of captopril on the beta-adrenergic system in noninfarcted myocardium in the rat heart failure model

1991 ◽  
Vol 17 (2) ◽  
pp. A133 ◽  
Author(s):  
Karil Bellah ◽  
Thomas Raya ◽  
Sheldon Litwin ◽  
Steven Goldman ◽  
Joel Karliner
Keyword(s):  
Heart Failure ◽  
Rat Heart ◽  
Adrenergic System ◽  
Failure Model ◽  
Beta Adrenergic ◽  
Heart Failure Model
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