OBJECTIVES: The present study evaluated the impact of recruitable collaterals on regional myocardial perfusion measured by 99mtechnetium (Tc)-sestamibi single-photon emission computerized tomography (SPECT) during temporary coronary occlusion and related these estimates to the coronary wedge pressure and electrocardiographic (ECG) ST-segment changes. BACKGROUND: Clinical variables (angina and ECG changes) and intracoronary flow and pressure recordings have indicated a protective role of recruitable collaterals on myocardial perfusion during percutaneous transluminal coronary angioplasty (PTCA). METHODS: Thirty patients (mean age 55 years, SD 9; 20 men) with stable angina pectoris and proximal nonocluding single-vessel left anterior descending coronary artery (LAD)-stenosis scheduled for PTCA were included. Visualization of recruitable collaterals by ipsilateral and contralateral contrast injection, registration of coronary wedge pressure and injection of 99mTc-sestamibi during 90-s LAD occlusions were undertaken. A rest perfusion study was performed within four days before PTCA. As an estimate of the severity of regional hypoperfusion during occlusion, an occlusion/rest count ratio was calculated (mean defect pixel count during occlusion divided by mean pixel count in identical regions at rest). RESULTS: The scintigraphic occlusion/rest count ratio was higher in patients with recruitable collaterals (n = 16), 67 +/- 11%, compared to patients without collaterals (n = 14), 60 +/- 6% (p < 0.05). The occlusion/rest count ratio correlated with the coronary wedge pressure (R2 = 0.34; p < 0.001). The occlusion/rest count ratio was lower, 61 +/- 6%, in patients with ST-segment elevation (n = 23) versus 74 +/- 9% in patients without ST-segment elevation (n = 7) (p < 0.0001). CONCLUSIONS: Using 99mTc-sestamibi SPECT imaging during brief episodes of coronary occlusion, the severity of regional myocardial hypoperfusion was reduced by the presence of recruitable collaterals in a selected patient population with proximal LAD stenoses. Our results demonstrate a protective effect of recruitable collaterals on myocardial perfusion during temporary coronary occlusion.
OBJECTIVES: The present study evaluated the impact of recruitable collaterals on regional myocardial perfusion measured by 99mtechnetium (Tc)-sestamibi single-photon emission computerized tomography (SPECT) during temporary coronary occlusion and related these estimates to the coronary wedge pressure and electrocardiographic (ECG) ST-segment changes. BACKGROUND: Clinical variables (angina and ECG changes) and intracoronary flow and pressure recordings have indicated a protective role of recruitable collaterals on myocardial perfusion during percutaneous transluminal coronary angioplasty (PTCA). METHODS: Thirty patients (mean age 55 years, SD 9; 20 men) with stable angina pectoris and proximal nonocluding single-vessel left anterior descending coronary artery (LAD)-stenosis scheduled for PTCA were included. Visualization of recruitable collaterals by ipsilateral and contralateral contrast injection, registration of coronary wedge pressure and injection of 99mTc-sestamibi during 90-s LAD occlusions were undertaken. A rest perfusion study was performed within four days before PTCA. As an estimate of the severity of regional hypoperfusion during occlusion, an occlusion/rest count ratio was calculated (mean defect pixel count during occlusion divided by mean pixel count in identical regions at rest). RESULTS: The scintigraphic occlusion/rest count ratio was higher in patients with recruitable collaterals (n = 16), 67 +/- 11%, compared to patients without collaterals (n = 14), 60 +/- 6% (p < 0.05). The occlusion/rest count ratio correlated with the coronary wedge pressure (R2 = 0.34; p < 0.001). The occlusion/rest count ratio was lower, 61 +/- 6%, in patients with ST-segment elevation (n = 23) versus 74 +/- 9% in patients without ST-segment elevation (n = 7) (p < 0.0001). CONCLUSIONS: Using 99mTc-sestamibi SPECT imaging during brief episodes of coronary occlusion, the severity of regional myocardial hypoperfusion was reduced by the presence of recruitable collaterals in a selected patient population with proximal LAD stenoses. Our results demonstrate a protective effect of recruitable collaterals on myocardial perfusion during temporary coronary occlusion.
Authors: Linda B Haramati; Jeffrey M Levsky; Vineet R Jain; Erik J Altman; Hugo Spindola-Franco; Shalini Bobra; Sanjay Doddamani; Mark I Travin Journal: Int J Cardiovasc Imaging Date: 2008-11-02 Impact factor: 2.357
Authors: T B Lindhardt; N Gadsbøll; H Kelbaek; K Saunamäki; J K Madsen; P Clemmensen; B Hesse; S Haunsø Journal: Heart Date: 2004-04 Impact factor: 5.994
Authors: Jessica de Vries; Rutger L Anthonio; Mike J L Dejongste; Gillian A Jessurun; Eng-Shiong Tan; Bart J G L de Smet; Ad F M van den Heuvel; Michiel J Staal; Felix Zijlstra Journal: BMC Cardiovasc Disord Date: 2007-06-27 Impact factor: 2.298