Left atrial systolic function in relation to electrical and mechanical remodeling in a canine model

2001 ◽  
Vol 442 (7) ◽  
pp. r195-r197 ◽  
Author(s):  
Igor Zupan ◽  
Mirta Koželj ◽  
Aleš Brecelj ◽  
Peter Rakovec ◽  
Irena Preložnik Zupan
Keyword(s):  
Left Atrial ◽  
Systolic Function ◽  
Canine Model ◽  
Mechanical Remodeling

scholarly journals P318 Left atrial dysfunction assessed by echocardiography in relation to left atrial fibrosis in patients undergoing ablation for atrial fibrillation

2020 ◽  
Vol 21 (Supplement_1) ◽  
Author(s):  
E Pilichowska ◽  
J Baran ◽  
P Kulakowski ◽  
B Zaborska
Keyword(s):  
Atrial Fibrillation ◽  
Left Atrial ◽  
Systolic Function ◽  
Electrophysiological Study ◽  
Stiffness Index ◽  
P Value ◽  
Group 2 ◽  
Left Atrial Dysfunction ◽  
Left Atrial Fibrosis ◽  
Group 1

Abstract PURPOSE Left atrial (LA) fibrosis is the hallmark of LA remodeling in atrial fibrillation (AF), alters LA function and may predict poor catheter ablation (CA) outcome. LA fibrosis may be assessed invasively using electroanatomical mapping (EAM) during electrophysiological study. The aim was to assess LA function parameters in relation to degree of LA fibrosis derived from EAM in patients with AF. METHODS Patients (pts) n = 39 (79% males, mean age 56+/-10) with non-valvular AF were studied with TTE and TEE before first CA during sinus rhythm. LA strain (LAS) and strain rate (LASR) were analyzed in reservoir (r), conduit (cd) and contractile (ct) phases. The velocities of mitral A, E" and A" were measured with Doppler. E/E" and LA stiffness index - the ratio of E/E" to LASr were assessed. LA appendage flow velocity (LAAv) was measured in TEE. LA volume using biplane area-length method was calculated. The EAM of LA was build using Carto System before CA. Low amplitude potentials area (LAPA) was quantitatively analyzed and expressed as a percentage of LA surface using the cut-off <0.5 mV to detect sites of fibrosis. LA parameters were compared between mild (LAPA <10%) moderate (LAPA 10-40%) and extensive degree of LA fibrosis (LAPA >40%) (table). RESULTS The mean LA volume was 35 ± 11 mL/m². The LAPA ranged from 2 to 78 % of LA surface. Reduced LA function was observed in the LAPA >40% group. Extensive LAPA altered mainly LA compliance parameters. Traditional LA systolic function parameters did not differ in relation to degree of LAPA. CONCLUSION LA compliance is mostly affected by LA fibrosis, thus LA diastolic parameters may be useful in the noninvasive assessment of LA fibrosis. Whether these parameters should be a part of the proper selection of candidates for CA requires further studies. LA function parameters LA parameters Group 1 LAPA <10% n = 13 Group 2 LAPA >10% <40% n = 13 Group 3 LAPA >40% n = 13 P-value Group 1 + 2 vs 3 Mitral A 0.55 ± 0.10 0.55 ± 0.24 0.73 ± 0.32 0.077 A" 9.19 ± 1.74 7.85 ± 1.43 7.92 ± 2.40 0.376 LASr 31.48 ± 4.52 26.48 ± 8.79 19.63 ± 6.76 <0.001 LAScd 17.30 ± 3.05 15.44 ± 6.93 10.91 ± 4.04 0.003 LASct 14.18 ± 5.36 11.05 ± 3.67 8.72 ± 4.78 0.024 LASRr 1.22 ± 0.19 1.24 ± 0.21 0.92 ± 0.20 <0.001 LASRct -1.71 ± 0.46 -1.37 ± 0.34 -1.04 ± 0.33 <0.001 LA stiffness 0.20 ± 0.07 0.34 ± 0.17 0.63 ± 0.29 <0.001 LAAv 0.83 ± 0.18 0.55 ± 0.17 0.60 ± 0.16 0.178

scholarly journals Acute Effects of Pimobendan on Cardiac Function in Dogs With Tachycardia Induced Dilated Cardiomyopathy: A Randomized, Placebo-Controlled, Crossover Study

2021 ◽  
Vol 8 ◽  
Author(s):  
Kaitlin Abbott-Johnson ◽  
Kursten V. Pierce ◽  
Steve Roof ◽  
Carlos L. del Rio ◽  
Robert Hamlin
Keyword(s):  
Heart Rate ◽  
Mitral Regurgitation ◽  
Dilated Cardiomyopathy ◽  
Diastolic Function ◽  
Cardiac Disease ◽  
Left Atrial ◽  
Survival Benefit ◽  
Systolic Function ◽  
Blood Draw ◽  
Post Dose

Background: Pimobendan provides a significant survival benefit in dogs with cardiac disease, including degenerative mitral valve disease and dilated cardiomyopathy (DCM). Its positive inotropic effect is well-known, however, it has complex effects and the mechanisms behind the survival benefit are not fully characterized. Secondary hemodynamic effects may decrease mitral regurgitation (MR) in DCM, and the benefits of pimobendan may extend to improved cardiac relaxation and improved atrial function.Hypothesis/Objectives: Our objective was to investigate the acute cardiac effects of pimobendan in dogs with a DCM phenotype. We hypothesized that pimobendan would increase left atrial (LA) contractility, reduce mitral regurgitation, improve diastolic function, and lower circulating NT-ProBNP levels.Animals: Seven purpose-bred Beagles were studied from a research colony with tachycardia induced DCM phenotype.Methods: The effects of pimobendan were studied under a placebo-controlled single-blinded cross-over design. In short, dogs underwent baseline and 3 h post-dose examinations 7 days apart with echocardiography and a blood draw. Dogs were randomized to receive oral placebo or 0.25 mg/kg pimobendan after their baseline exam. Investigators were blinded to treatments until all measurements were compiled.Results: When treated with pimobendan, the dogs had significant increases in systolic function and decreases in MR, compared to when treated with placebo.There were no detectable differences in left atrial measures, including LA size, LA emptying fraction, LA functional index or mitral A wave velocity. Heart rate decreased significantly with pimobendan compared to placebo. There was also a decrease in isovolumetric relaxation time normalized to heart rate. NT-proBNP levels had a high degree of variability.Conclusions: Improved mitral regurgitation severity and improved lusitropic function may contribute to the reported survival benefit for dogs with cardiac disease administered pimobendan. Pimobendan did not overtly improve LA function as assessed by echocardiography, and NT-proBNP was not significantly changed with a single dose of this medication. Further studies are needed to better characterize LA effects with other imaging modalities, to better quantify the total improvement of MR severity, and to assess chronic use of pimobendan on diastolic function in DCM.

Bachmann's Bundle and Coronary Sinus Ostial Pacing Accentuate Left Atrial Electrical Dyssynchrony in an Acute Canine Model

2014 ◽  
Vol 25 (12) ◽  
pp. 1400-1406
Author(s):  
INDRAJIT CHOUDHURI ◽  
DAVID KRUM ◽  
ANUJ AGARWAL ◽  
JOHN HARE ◽  
MAREK BELOHLAVEK ◽  
...  
Keyword(s):  
Coronary Sinus ◽  
Left Atrial ◽  
Canine Model ◽  
Bachmann’S Bundle

Relation of left atrial volume and systolic function to the hormonal response in idiopathic dilated cardiomyopathy

1994 ◽  
Vol 47 (2) ◽  
pp. 139-143 ◽  
Author(s):  
Athanasios Trikas ◽  
Filippos Triposkiadis ◽  
Christos Pitsavos ◽  
Konstantinos Tentolouris ◽  
Michael Kyriakidis ◽  
...  
Keyword(s):  
Dilated Cardiomyopathy ◽  
Left Atrial ◽  
Systolic Function ◽  
Left Atrial Volume ◽  
Idiopathic Dilated Cardiomyopathy ◽  
Hormonal Response ◽  
Atrial Volume

scholarly journals Prolonged effects of B-type natriuretic peptide infusion on cardiac remodeling after sustained myocardial injury

2009 ◽  
Vol 297 (2) ◽  
pp. H708-H717 ◽  
Author(s):  
Isaac George ◽  
Brad Morrow ◽  
Kai Xu ◽  
Geng-Hua Yi ◽  
Jeffrey Holmes ◽  
...  
Keyword(s):  
Natriuretic Peptide ◽  
Myocardial Injury ◽  
Acute Decompensated Heart Failure ◽  
Systolic Function ◽  
Ischemic Injury ◽  
Decompensated Heart Failure ◽  
Canine Model ◽  
Left Ventricular ◽  
Saline Control ◽  
Coronary Embolization

B-type natriuretic peptide (BNP) is an established first-line therapy for acute decompensated heart failure (HF), but its efficacy in preventing left ventricular (LV) remodeling after myocardial injury is unknown. The goal of this study was to evaluate the effects of BNP therapy on remodeling after ischemic injury in an awake canine model. Dogs were chronically instrumented for hemodynamics. Ischemia was created by daily coronary embolization (Embo; 3.1 × 104 beads/day) for 3 wk; 60 min after the first embolization, BNP (100 ng·kg−1·min−1; n = 6) or saline (control; n = 6) was continuously infused via a left atrial catheter for 3 wk. Hemodynamics and echocardiography were performed in an awake state at baseline, 3 wk after Embo + BNP infusion, and 4 wk after stopping Embo + BNP infusion. End-systolic elastance (Ees) and LV change in pressure over time (dP/d t) were preserved throughout Embo + BNP therapy versus control therapy (Ees: 3.76 ± 1.01 vs. 1.41 ± 0.16 mmHg/ml; LV dP/d t: 2,417 ± 96 vs. 2,068 ± 95 mmHg/s; both P < 0.05 vs. control). LV end-diastolic dimension was significantly smaller in BNP-treated dogs compared with control dogs (4.29 ± 0.10 vs. 4.77 ± 0.17 cm), and ejection fraction was maintained in treated dogs vs. control dogs (53 ± 1% vs. 46 ± 2%) (both P < 0.05 vs. control). Cyclooxygenase (COX)-2 expression in terminal LV tissue was significantly reduced after BNP therapy. Treatment with continuous infusion of BNP preserved LV geometry, improved systolic function, and prevented the progression of systolic HF after persistent ischemic injury.

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