Recovery of myocardial perfusion after percutaneous coronary intervention of chronic total occlusions is comparable to hemodynamically significant non‐occlusive lesions

Abstract

Background The benefits of chronic coronary total occlusion (CTO) percutaneous coronary intervention (PCI) are being questioned. The aim of this study was to assess the effects of CTO PCI on absolute myocardial perfusion, as compared with PCI of hemodynamically significant non‐CTO lesions. Methods Consecutive patients with a preserved left ventricular ejection fraction (≥50%) and a CTO or non‐CTO lesion, in whom [15O]H2O positron emission tomography was performed prior and after successful PCI, were included. Change in quantitative (hyperemic) myocardial blood flow (MBF), coronary flow reserve (CFR) and perfusion defect size (in myocardial segments) were compared between CTOs and non‐CTO lesions. Results In total 92 patients with a CTO and 31 patients with a non‐CTO lesion were included. CTOs induced larger perfusion defect sizes (4.51 ± 1.69 vs. 3.23 ± 2.38 segments, P < 0.01) with lower hyperemic MBF (1.30 ± 0.37 vs. 1.58 ± 0.62 mL·min−1·g−1, P < 0.01) and similarly impaired CFR (1.66 ± 0.75 vs. 1.89 ± 0.77, P = 0.17) compared with non‐CTO lesions. After PCI both hyperemic MBF and CFR increased similarly between groups (P = 0.57 and 0.35) to normal ranges with higher hyperemic MBF values in non‐CTO compared with CTO (2.89 ± 0.94 vs. 2.48 ± 0.73 mL·min−1·g−1, P = 0.03). Perfusion defect sizes decreased similarly after CTO PCI and non‐CTO PCI (P = 0.14), leading to small residual defect sizes in both groups (1.15 ± 1.44 vs. 0.61 ± 1.45 segments, P = 0.054). Conclusions Myocardial perfusion findings are slightly more hampered in patients with a CTO before and after PCI. Percutaneous revascularization of CTOs, however, improves absolute myocardial perfusion similarly to PCI of hemodynamically significant non‐CTO lesions, leading to satisfying results.

Chronic total occlusion or non‐chronic total occlusion percutaneous coronary intervention: Do myocytes really care?

“…The present study of Schumacher SP et al published in this issue has shed light on a very key question—are CTOs a completely different animal compared to non‐CTOs? Does holding them to different scrutiny make physiological sense?…”

Coronary computed tomography angiography and [15O]H2O positron emission tomography perfusion imaging for the assessment of coronary artery disease

“…Of note, all patients had an indication for evaluation of the CTO with the majority of patients (>80%) being symptomatic. Furthermore, the extent and depth of ischaemia was observed to be more profound in patients with a CTO as compared with patients with severe haemodynamically significant lesions as determined by FFR (mean FFR: 0.55 ± 0.19) [10,40]. These findings may be expected given the absence of antegrade flow and the complete dependence of myocardium subtended by a CTO on collateral supply.…”

Serial fractional flow reserve, coronary flow reserve and index of microcirculatory resistance after percutaneous coronary intervention in patients treated for stable angina pectoris assessed with PET

“…The positive impact on absolute perfusion after revascularization has previously been documented in patients with stable angina pectoris [ 19 – 22 ]. When we compared the revascularized territory to the reference territory, we were able to document not only an improvement of the absolute perfusion after revascularization but also a perfusion that did not differ from that of the reference territory.…”