Faculty Collaboration Database

The effect of percutaneous transmyocardial laser revascularization on left ventricular function in a porcine model of hibernating myocardium: a pilot study. Cardiovasc Radiat Med 2004;5(3):132-5

Date

02/22/2005

Pubmed ID

15721848

DOI

10.1016/j.carrad.2004.11.002

Scopus ID

2-s2.0-13944258560 (requires institutional sign-in at Scopus site)   3 Citations

Abstract

BACKGROUND: Hibernating myocardium is defined as a state of persistently impaired myocardial function at rest due to reduced coronary blood flow that can partially or completely be restored to normal if the myocardial oxygen supply/demand relationship is favorably altered. Percutaneous laser revascularization (PMR) is an emerging catheter-based technique that involves creating channels in the myocardium, directly through a percutaneous approach with a laser delivery system, and has been shown to reduce symptoms in patients with severe refractory angina; however, its effect on improving regional wall motion abnormalities in hibernating myocardium has not been clearly established. We sought to determine the effect of PMR using the Eclipse System (Cardiogenesis) on left ventricular function in a porcine model of hibernating myocardium.

METHODS: A model of hibernating myocardium was created by placement of an ameroid constrictor in the proximal left anterior descending artery of a 35 kg male Yorkshire pig. The presence of hibernating myocardium was confirmed with dobutamine stress echocardiography (DSE) and defined as severe hypocontractility at rest, with an improvement in systolic wall thickening with low-dose dobutamine in myocardial regions with a subsequent deterioration in function at peak stress (biphasic response). After the demonstration of hibernating myocardium, PMR was performed in the area of hypocontractile function, and the serial echocardiography was performed. The echocardiograms were reviewed by an experienced echocardiologist blinded to the results, and regional wall motion was assessed using the American Society of Echocardiography Wall Motion Score. Six weeks after PMR, the animal was sacrificed and the heart sent for histopathologic studies.

RESULTS: A comparison of the regional wall motion function of the area distal to the ameroid constrictor and in the contralateral wall at baseline, post-ameroid placement, and post-PMR was performed. Hibernating myocardium was demonstrated 4 weeks after ameroid placement by DSE. Coronary angiography demonstrated a discrete 90%stenosis in the proximal LAD at the site of ameroid constrictor placement without evidence of collaterals. Using PMR, 17 bursts were successfully delivered to the anterior wall distal to the ameroid constrictor. Four weeks after PMR, there was improvement in wall motion function in the region distal to the ameroid placement by echocardiography. Histopathologic analysis demonstrated the absence of myocardial infarction in the anterior wall distal to the ameroid constrictor.

CONCLUSIONS: The performance of PMR in a porcine model of hibernating myocardium is feasible and is associated with an improvement regional wall motion function after 4 weeks.

Author List

Almeda FQ, Glock D, Sandelski J, Ibrahim O, Macioch JE, Allen T, Dainauskas JR, Parrillo JE, Snell RJ, Schaer GL

MESH terms used to index this publication - Major topics in bold

Animals
Disease Models, Animal
Echocardiography
Laser Therapy
Myocardial Revascularization
Myocardial Stunning
Pilot Projects
Swine
Ventricular Dysfunction, Left