Key Points
- To determine the temporal patterns of collateral blood flow changes in salvaged versus infarcted myocardium within the area at risk during the first 24 hours following coronary artery occlusion.
- Conducted a retrospective analysis in conscious dogs subjected to coronary artery occlusion, assessing blood flow at 5 minutes, 1 hour, 3 hours, 6 hours, and 24 hours.
- Quantified regional myocardial blood flow using the radioactive microsphere technique and delineated infarcted (TTC-negative) from salvaged (TTC-positive) tissue using triphenyl tetrazolium chloride staining.
- Salvaged tissue exhibited progressive increases in collateral blood flow across all measurement intervals (5 min to 1 h, 1 to 3 h, 3 to 6 h, and 6 to 24 h), whereas infarcted tissue showed blood flow increases only between 6 and 24 hours post-occlusion.
- Virtually all tissue samples with blood flow levels below 0.1 ml·min⁻¹·g⁻¹ became infarcted, whereas flow rates exceeding 0.1 ml·min⁻¹·g⁻¹ at isolated time points failed to reliably predict myocardial necrosis.
Structured PICO
PPopulationConscious dogs subjected to coronary artery occlusion (CAO)
IInterventionCoronary artery occlusion (CAO)
CComparatorInfarcted (TTC-negative) versus salvaged (TTC-positive) tissue samples
OOutcomePatterns of collateral blood flow changes within the area at risk during the first 24 hours after CAOsurrogate
In a conscious dog model of coronary occlusion, collateral blood flow increases progressively in salvaged myocardium but not in infarcted tissue, though flow levels alone cannot reliably predict necrosis unless <0.1 ml/min/g.