Journal article
Effects of single-ventricle physiology with aortopulmonary shunt on regional myocardial blood flow in a piglet model
The Journal of thoracic and cardiovascular surgery, Vol.132(2), pp.252-259
2006
DOI: 10.1016/j.jtcvs.2006.03.050
PMID: 16872946
Abstract
Objectives
In single-ventricle physiology with aortopulmonary connection, diastolic hypotension could alter regional myocardial blood flow. Also, afterload increases could impair myocardial blood flow by increased wall tension and relative subendocardial malperfusion. This study explores the effects of acute single-ventricle physiology on regional myocardial blood flow distribution and investigates the consequences of moderate afterload augmentation on myocardial blood flow.
Methods
Single-ventricle physiology was created in 8 piglets without using bypass, and 8 animals served as a sham control group. Aortopulmonary shunt, echo-guided atrial septostomy, tricuspid valve avulsion, and pulmonary artery occlusion allowed the left ventricle to support systemic and pulmonary circulations. Afterload augmentation was produced by aortic balloon inflation. Physiologic recordings and stable-isotope microsphere determination of myocardial blood flow to the subepicardium and subendocardium were obtained at baseline and during single-ventricle physiology (at 30 minutes, 120 minutes, and afterload increase).
Results
Arterial oxygen content, diastolic pressure, and coronary perfusion pressure declined after creation of single-ventricle physiology (P < .05). Acute single-ventricle physiology resulted in higher myocardial blood flow (P < .05), unchanged subendocardial/subepicardial flow ratio and oxygen delivery, and lower coronary resistance (P < .01) as compared with biventricular physiology. Afterload augmentation increased coronary perfusion pressure, causing a trend for higher myocardial blood flow and oxygen delivery (P = NS), without affecting subendocardial/subepicardial flow distribution. Myocardial oxygen supply/demand balance fell in single-ventricle physiology, remaining unchanged during afterload augmentation.
Conclusions
Our study demonstrates that, in acute single-ventricle physiology with aortopulmonary shunt, myocardial blood flow is maintained by lower coronary perfusion pressure. Further, single-ventricle physiology results in less favorable myocardial oxygen supply/demand balance, although normal transmural myocardial blood flow distribution is maintained. Avoidance of diastolic runoff (ventricle-pulmonary conduit) could improve coronary reserve. In our study, moderate afterload augmentation did not induce relative subendocardial malperfusion, nor did it worsen oxygen supply/demand balance.
Details
- Title: Subtitle
- Effects of single-ventricle physiology with aortopulmonary shunt on regional myocardial blood flow in a piglet model
- Creators
- Marco RICCI - Holtz Children's Hospital, University of Miami Miller School of Medicine, Miami, Fla, United StatesPierluca LOMBARDI - Holtz Children's Hospital, University of Miami Miller School of Medicine, Miami, Fla, United StatesAlvaro GALINDO - Holtz Children's Hospital, University of Miami Miller School of Medicine, Miami, Fla, United StatesSteven SCHULTZ - Holtz Children's Hospital, University of Miami Miller School of Medicine, Miami, Fla, United StatesAmelia VASQUEZ - Holtz Children's Hospital, University of Miami Miller School of Medicine, Miami, Fla, United StatesEliot ROSENKRANZ - Holtz Children's Hospital, University of Miami Miller School of Medicine, Miami, Fla, United States
- Resource Type
- Journal article
- Publication Details
- The Journal of thoracic and cardiovascular surgery, Vol.132(2), pp.252-259
- Publisher
- Elsevier; Philadelphia, PA
- DOI
- 10.1016/j.jtcvs.2006.03.050
- PMID
- 16872946
- ISSN
- 0022-5223
- eISSN
- 1097-685X
- Language
- English
- Date published
- 2006
- Academic Unit
- Surgery; Cardiothoracic Surgery
- Record Identifier
- 9984051569402771
Metrics
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