Spontaneous recovery of myocardial function after ligation of Ameroid-stenosed coronary artery.
OBJECTIVE
We aimed to assess the spontaneous healing of myocardial function after occlusion of a chronically stenosed coronary vessel in a porcine model.


METHODS
Ischemia and infarction was produced by Ameroid constrictor placement and a subsequent ligation of the left circumflex artery. Cardiac MRI and 18FDG-PET were performed one and five weeks later. Ki67 staining was used to identify proliferating cells.


RESULTS
Restoration of perfusion defect was detected by MRI (p=0.0065), reduced systolic function of the lateral segment spontaneously recovered (p=0.03). There was also a suggestive raise in impaired ejection fraction (p=0.06). Left ventricular early diastolic filling and peak filling rate were substantially improved (p=0.039 and p=0.0078). Scar size reduced (p=0.03). On the 18FDG-PET, deranged metabolism was alleviated (p=0.03). Cardiomyocytes with positive Ki-67 staining were located principally in the non-infarcted myocardium as compared to the infarction or border areas (p=0.037).


CONCLUSIONS
We demonstrated spontaneous functional healing of ischemic and infarcted left ventricle, suggesting border zone perfusion recovery. Scar reduction was detected. Different pattern of myocyte proliferation between infarction and non-ischemic myocardium was seen.
Department of Cardiothoracic Surgery, University of Helsinki Meilahti Hospital, Finland. tommi.patila@hus.fi
Tommi
T
Pätilä
Tuija
T
Ikonen
Esko
E
Kankuri
Aapo
A
Ahonen
Leena
L
Krogerus
Kirsi
K
Lauerma
Ari
A
Harjula
D000818:Animals; D002455:Cell Division; D003326:Coronary Circulation; D003971:Diastole; D005947:Glucose / Q000378:metabolism; D006321:Heart / Q000502:physiology*; D008026:Ligation; D008279:Magnetic Resonance Imaging; D009203:Myocardial Infarction / Q000473:pathology* / Q000503:physiopathology; D009206:Myocardium / Q000378:metabolism / Q000473:pathology*; D032383:Myocytes, Cardiac / Q000502:physiology; D049268:Positron-Emission Tomography; D012038:Regeneration; D012075:Remission, Spontaneous; D013552:Swine; D013599:Systole; D016277:Ventricular Function, Left
D005947:Glucose