Critical single proximal left arterial descending coronary artery stenosis to mimic chronic myocardial ischemia: a new model induced by minimal invasive technology.
OBJECTIVE
The present report examines a new pig model for progressive induction of high-grade stenosis, for the study of chronic myocardial ischemia and the dynamics of collateral vessel growth.


METHODS
Thirty-nine Landrace pigs were instrumented with a novel experimental stent (GVD stent) in the left anterior descending coronary artery. Eight animals underwent transthoracic echocardiography at rest and under low-dose dobutamine. Seven animals were examined by nuclear PET and SPECT analysis. Epi-, mid- and endocardial fibrosis and the numbers of arterial vessels were examined by histology.


RESULTS
Functional analysis showed a significant decrease in global left ventricular ejection fraction (24.5 +/- 1.6%) 3 weeks after implantation. There was a trend to increased left ventricular ejection fraction after low-dose dobutamine stress (36.0 +/- 6.6%) and a significant improvement of the impaired regional anterior wall motion. PET and SPECT imaging documented chronic hibernation. Myocardial fibrosis increased significantly in the ischemic area with a gradient from epi- to endocardial. The number of arterial vessels in the ischemic area increased and coronary angiography showed abundant collateral vessels of Rentrop class 1.


CONCLUSIONS
The presented experimental model mimics the clinical situation of chronic myocardial ischemia secondary to 1-vessel coronary disease.
Horstick
Georg
G
Second Medical Clinic, Johannes Gutenberg University Mainz, Mainz, Germany. horstick@uni-mainz.de
Bierbach
Benjamin
B
Abegunewardene
Nico
N
Both
Stefan
S
Kuhn
Sebastian
S
Manefeld
Dirk
D
Reinecke
Hans-Jürgen
HJ
Vosseler
Markus
M
Helisch
Andreas
A
Becker
Dietmar
D
Lauterbach
Michael
M
Kempski
Oliver
O
Lehr
Hans-Anton
HA
D015906:Angioplasty, Balloon, Coronary / Q000009:adverse effects* / Q000295:instrumentation; D000818:Animals; D002908:Chronic Disease; D003097:Collateral Circulation; D017023:Coronary Angiography; D003326:Coronary Circulation; D023921:Coronary Stenosis / Q000150:complications* / Q000175:diagnosis / Q000209:etiology / Q000503:physiopathology; D003331:Coronary Vessels / Q000473:pathology / Q000503:physiopathology*; D016638:Critical Illness; D004195:Disease Models, Animal; D025401:Echocardiography, Stress; D005260:Female; D005355:Fibrosis; D008297:Male; D017202:Myocardial Ischemia / Q000175:diagnosis / Q000209:etiology* / Q000503:physiopathology; D049268:Positron-Emission Tomography; D012720:Severity of Illness Index; D015607:Stents / Q000009:adverse effects*; D013318:Stroke Volume; D013552:Swine; D013997:Time Factors; D015899:Tomography, Emission-Computed, Single-Photon; D018487:Ventricular Dysfunction, Left / Q000209:etiology / Q000503:physiopathology