title: Correlation between the high-frequency content of the QRS on murine surface electrocardiogram and the sympathetic nerves density in left ventricle after myocardial infarction: Experimental study.
abstract: Denervated post-infarct scar is arrhythmogenic. Our aim was to compare QRS frequency content in denervated and innervated left ventricular (LV) scar. In-vivo single lead ECG telemetry device was implanted in 17 heterozygous PTPσ (HET) and 7 lacking PTPσ (KO) transgenic mice. Myocardial infarction (MI) with reperfusion and sham surgery was performed. HET mice developed a denervated scar, whereas KO mice developed innervated scar. The power spectral density was used to assess the QRS frequency content. Denervated as compared to innervated post-MI scar was characterized by the higher relative contribution of 300-500 Hz (14 ± 1 vs. 9 ± 1%; P = 0.001) but reduced relative contribution of 200-300 Hz (86 ± 1 vs. 91 ± 1%; P = 0.001). Norepinephrine concentration in peri-infarct zone correlated with both 1-200 Hz (r = 0.75; P = 0.03) and 200-500 Hz QRS power (r = 0.73; P = 0.04). Sympathetic fiber density within the infarct correlated with 200-300/200-500 Hz QRS power ratio (r = 0.56; P = 0.005). Intracellular sigma peptide injections in post-MI HET mice restored the QRS power.
authors.affiliation: Knight Cardiovascular Institute, Oregon Health & Science University, Portland, OR, USA; Portland State University, Portland, OR, USA.
authors.forename: Golriz
authors.initials: G
authors.lastname: Sedaghat
authors.affiliation: Department of Physiology and Pharmacology, Oregon Health and Science University, Portland, OR, USA.
authors.forename: Ryan T
authors.initials: RT
authors.lastname: Gardner
authors.affiliation: Knight Cardiovascular Institute, Oregon Health & Science University, Portland, OR, USA.
authors.forename: Muammar M
authors.initials: MM
authors.lastname: Kabir
authors.affiliation: Knight Cardiovascular Institute, Oregon Health & Science University, Portland, OR, USA; University of Utah, Salt Lake City, UT, USA.
authors.forename: Elyar
authors.initials: E
authors.lastname: Ghafoori
authors.affiliation: Department of Physiology and Pharmacology, Oregon Health and Science University, Portland, OR, USA.
authors.forename: Beth A
authors.initials: BA
authors.lastname: Habecker
authors.affiliation: Knight Cardiovascular Institute, Oregon Health & Science University, Portland, OR, USA. Electronic address: tereshch@ohsu.edu.
authors.forename: Larisa G
authors.initials: LG
authors.lastname: Tereshchenko
mesh_terms: D000818:Animals; D004569:Electroencephalography / Q000379:methods*; D005260:Female; D006329:Heart Conduction System / Q000503:physiopathology*; D006352:Heart Ventricles / Q000294:innervation* / Q000503:physiopathology*; D008297:Male; D051379:Mice; D008822:Mice, Transgenic; D009203:Myocardial Infarction / Q000150:complications / Q000503:physiopathology*; D017682:Myocardial Stunning / Q000209:etiology / Q000503:physiopathology*; D015203:Reproducibility of Results; D012680:Sensitivity and Specificity; D013564:Sympathetic Nervous System / Q000473:pathology / Q000503:physiopathology*
keywords: Electrocardiogram; Post-myocardial infarction scar; Sympathetic nervous system