940-75 Effect of Coronary Revascularization on Left Ventricular Remodeling in Patients Receiving Thrombolytic Therapy for Myocardial Infarction: A One Year Follow-up

Introduction: Vagus nerve stimulation (VNS) attenuates left ventricular remodeling after myocardial infarction (MI) by improving the imbalance of autonomic nervous system. Our previous study found Low-level tragus stimulation (LL-TS) had the same antiarrhythmic effects as VNS by regulation of the autonomic nervous system. Hypothesis: Chronic intermittent LL-TS could attenuate left ventricular remodeling in conscious dogs with healed myocardial infarction. Methods: Thirty beagle dogs were randomly divided into three groups. LL-TS group (n=10) and MI group (n=10) underwent left anterior descending coronary artery and all major diagonal branches ligation to introduce MI under general anesthesia. Control group (n=10) underwent sham surgery. Auricular vagus nerve stimulation (frequency 20Hz, pulse width 1ms) with duty cycle of 5s on and 5s off was delivered to the bilateral tragus in external auditory canal with ear-clips connected to a custom-made stimulator. The voltage slowing sinus rate was used as the threshold for setting LL-TS at 80% below that. The actual voltage of stimulation was in the range of 16 to 24V that did not cause any heart rate changes. LL-TS group was given four hours of LL-TS at 7-9AM and 4-6PM on conscious dogs from the day of MI introduction to the end of 90-day follow-up, MI group and control group were given no stimulations. Results: At the end of 90-days follow-up LL-TS group significantly reduced left ventricular dilatation, improve left ventricular contractile and diastolic function, reduced mean infarct size by about 50% compared with MI group. Also LL-TS treatment alleviated cardiac fibrosis around infarction border and significantly decreased protein level of collagen I, collagen III, TGF-β1, MMP-9 in noninfarcted left ventricular free wall tissue after MI. Moreover, the plasma level of hs-CRP, NE and NT-proBNP in LL-TS group was significantly lower than MI group from the 7th day to the end of follow-up. Conclusions: Chronic intermittent low-level transcutaneous electrical stimulation of the auricular branch of the vagus nerve can attenuate left ventricular remodeling and improve cardiac function in conscious dogs with healed myocardial infarction.

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The influence of thrombolytic therapy on clinical and instrumental parameters of left ventricular remodeling in the late post-infarction period of myocardial infarction with Q-wave

Kazan medical journal ◽

10.17816/kmj1709 ◽

2012 ◽

Vol 93 (5) ◽

pp. 777-782

Author(s):

G M Khairutdinova

Keyword(s):

Myocardial Infarction ◽

Thrombolytic Therapy ◽

Wave Amplitude ◽

Ventricular Remodeling ◽

Left Ventricular Remodeling ◽

Left Ventricular ◽

Wall Thickening ◽

Initial Symptom ◽

R Wave Amplitude ◽

Q Wave

Aim. To evaluate clinical and instrumental parameters of late left ventricular remodeling in patients with myocardial infarction with Q-wave depending on use of thrombolysis. Methods. 87 patients with myocardial infarction with Q-wave on electrocardiography (ECG) were included. First group consisted of 34 patients in whom thrombolytic therapy was performed, second group consisted of 53 patients in whom thrombolysis was not used due to late referral (over 12 hours from initial symptom onset, 88,7%), concomitant hemorrhagic stroke (3,8%), previously reported uncontrolled arterial hypertension (7,6%). All patients were followed up at 3-4 weeks, 60 and 120 months after the onset of myocardial infarction, examination included ECG, echocardiography, clinical examination. Results. In patients of both groups increase of total R-wave amplitude on repetitive ECGs was associated with relative left ventricle wall thickening, increase of left ventricular mass index, decrease of systolic and diastolic wall stresses caused by compensatory hypertrophy of intact cardiomyocytes according to results of correlation analysis. Increase of total amplitude of QS-waves on repetitive ECGs was associated with left ventricular cavity dilatation and spherification with wall thickening, increase of systolic and diastolic wall stresses. Patients in whom thrombolysis was not used had significantly higher rates of angina at post-infarction period. No statistically significant differences of ECG and echocardiography parameters between two groups of patients were found during the whole follow-up period. Non-significant increase of total R-wave amplitude and QS-waves amplitude was registered in patients in whom thrombolysis was started not later than 90 minutes from initial symptom onset compared to patients in whom thrombolysis was started later. Conclusion. Comparison of ECG and echocardiography parameters over time did not reveal any statistically significant differences between the groups with and without thrombolysis.

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Long Term Follow Up and Outcome of Left Ventricular Remodeling in ST Segment Myocardial Infarction Patients After pPCI

Case Medical Research ◽

10.31525/ct1-nct03888781 ◽

2019 ◽

Author(s):

Keyword(s):

Myocardial Infarction ◽

Ventricular Remodeling ◽

Left Ventricular Remodeling ◽

Left Ventricular ◽

St Segment ◽

Long Term Follow Up

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Left atrial strain is associated with left ventricular remodeling in patients with ST-elevation myocardial infarction

European Heart Journal ◽

10.1093/ehjci/ehaa946.1582 ◽

2020 ◽

Vol 41 (Supplement_2) ◽

Author(s):

D Legallois ◽

A Hodzic ◽

P Milliez ◽

A Manrique ◽

E Saloux ◽

...

Keyword(s):

Myocardial Infarction ◽

Left Atrial ◽

Ventricular Remodeling ◽

Left Ventricular Remodeling ◽

Left Ventricular ◽

St Elevation Myocardial Infarction ◽

Left Ventricular Ejection ◽

Volume Increase ◽

St Elevation

Abstract Background/Introduction Left ventricular remodeling (LVR) remains common and is associated with outcomes in patients with ST-elevation myocardial infarction (STEMI). Left atrial (LA) volume has been described as a predictor of outcomes in the latter population. Purpose To investigate the association between LA mechanical function using speckle tracking imaging and LVR at follow-up in STEMI patients. Methods Baseline 3D transthoracic echocardiograms were performed in 121 STEMI patients. LA global longitudinal strain was reported separately for the reservoir (LASr), conduit (LAScd), and contraction (LASct) phases. Follow-up echocardiograms were performed at 6 months. Results Mean age was 58.3±12.5 years and 98 (81%) were men. Baseline left ventricular ejection fraction (LVEF) was 46.8% [41.0, 52.9] and significantly improved to 52.1% [45.8, 57.0] at follow-up, (p<0.001). A lower LASct was associated with a significant dilation of left ventricle at follow-up (%end-diastolic volume increase: −1.9% [−11.0, 15.2] in the two higher LASct tertiles group vs. 19.2% [5.0, 34.3] in the lower LASct tertile group, p=0.001). A higher %end-systolic volume increase at follow-up was associated with lower LASct as well: 12.6% [−16.2, 39.8] in the lower LASct group vs. −6.8% [−23.6, 14.4] in the two higher LASct tertiles group (p=0.004). Regarding LVEF, a low LVEF at follow-up was associated with the worst tertile of all LA strains (LASr, p=0.002; LAScd, p=0.01 and LASct, p=0.01). Conclusion(s) The three components of baseline LA strain were associated with LVEF at follow-up in patients with STEMI. Some of these components were also significantly associated with lower LVEF at baseline or predictive of a significant increase in left ventricular volumes during follow-up, indicating LVR. Funding Acknowledgement Type of funding source: None

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