Stefan P. Schumacher

Subadventitial stenting around occluded stents: A bailout technique to recanalize in-stent chronic total occlusions

To evaluate the outcomes of subadventitial stenting (SS) around occluded stents for recanalizing in‐stent chronic total occlusions (IS‐CTOs).

Effects of successful percutaneous coronary intervention of chronic total occlusions on myocardial perfusion and left ventricular function

AIMS The aim of the present study was to investigate the effects of successful PCI CTO on absolute myocardial blood flow (MBF) and functional recovery. METHODS AND RESULTS Patients with a documented CTO were prospectively examined for ischaemia and viability with [15O]H2O positron emission tomography (PET) and late gadolinium enhancement cardiac magnetic resonance imaging (LGE-CMR). Sixty-nine consecutive patients, in whom PCI was successful, underwent follow-up PET and CMR after approximately 12 weeks to evaluate potential improvement of MBF as well as systolic function. After PCI, stress MBF in the CTO area increased from 1.22±0.36 to 2.40±0.90 mL·min-1·g-1 (p<0.001), whilst stress MBF in the remote area also increased significantly between baseline and follow-up PET (2.58±0.68 to 2.77±0.77 mL·min-1·g-1, p=0.01). The ratio of stress MBF between CTO and remote area was 0.49±0.13 at baseline and increased to 0.87±0.24 at follow-up (p<0.001). The MBF defect size of the CTO area decreased from 5.12±1.69 to 1.91±1.75 myocardial segments after PCI (p<0.001). Left ventricular ejection fraction (LVEF) increased significantly (46.4±11.0 vs. 47.5±11.4%, p=0.01) at follow-up. CONCLUSIONS The vast majority of CTO patients with documented ischaemia and viability showed significant improvement in stress MBF and a reduction of ischaemic burden after successful percutaneous revascularisation with only minimal effect on LVEF.

Retrograde Chronic Total Occlusion Percutaneous Coronary Intervention Through Ipsilateral Collateral Channels: A Multicenter Registry

OBJECTIVES The aim of this study was to describe the procedural aspects and outcomes of retrograde chronic total occlusion (CTO) percutaneous coronary intervention (PCI) through ipsilateral collateral channels (ILCs). BACKGROUND Retrograde CTO PCI via ILCs is rarely performed, usually when no other retrograde options exist, and available evidence derives mostly from case reports. METHODS A large retrospective multinational registry was compiled, including all consecutive patients undergoing retrograde CTO PCI through ILCs at 6 centers between September 2011 and October 2016. Success rates, as well as procedural complications and in-hospital outcomes, were studied. RESULTS A total of 126 patients (17% of all retrograde CTO PCIs) were included. The mean age was 65.7 ± 11.2 years, and the mean J-CTO (Multicenter CTO Registry in Japan) score was 2.36 ± 1.13. The target vessel was the circumflex coronary artery in 42%, the left anterior descending coronary artery in 39%, and the right coronary artery in 19%. The ILCs used were epicardial in 76% and septal in 24%. ILC anatomy was very heterogeneous. One guiding catheter was used in 80%, whereas the ping-pong technique was used in 20%. A retrograde wire could be advanced to the distal cap in 81%. Technical and procedural success rates were 87% and 82%, respectively. ILC perforation with need for intervention was observed in 5.6% and tamponade due to ILC perforation in 2.4%. One patient (0.8%) died. CONCLUSIONS Retrograde CTO PCI through ILCs is a challenging intervention that can be performed in difficult occlusions with high success rates and reasonable rates of complications by experienced operators.

Impact of Revascularization on Absolute Myocardial Blood Flow as Assessed by Serial [15O]H2O Positron Emission Tomography Imaging: A Comparison With Fractional Flow Reserve

Background: The main goal of coronary revascularization is to restore myocardial perfusion in case of ischemia, causing coronary artery disease. Yet, little is known on the effect of revascularization on absolute myocardial blood flow (MBF). Therefore, the present prospective study assesses the impact of coronary revascularization on absolute MBF as measured by [15O]H2O positron emission tomography and fractional flow reserve (FFR) in patients with stable coronary artery disease. Methods and Results: Fifty-three patients (87% men, mean age 58.7±9.0 years) with suspected coronary artery disease were included prospectively. All patients underwent serial [15O]H2O positron emission tomography perfusion imaging at baseline and after revascularization by either percutaneous coronary intervention (PCI) or coronary artery bypass graft surgery. FFR was routinely measured at baseline and directly post-PCI. After revascularization, regional rest and stress MBF improved from 0.77±0.16 to 0.86±0.25 mL/min/g and from 1.57±0.59 to 2.48±0.91 mL/min/g, respectively, yielding an increase in coronary flow reserve from 2.02±0.69 to 2.94±0.94 (P<0.01 for all). Mean FFR at baseline improved post-PCI from 0.61±0.17 to 0.89±0.08 (P<0.01). After PCI, an increase in FFR paralleled improvement in absolute myocardial perfusion as reflected by stress MBF and coronary flow reserve (r = 0.74 and r = 0.71, respectively, P<0.01 for both). PCI demonstrated a greater improvement of regional stress MBF as compared with coronary artery bypass graft surgery (1.14±1.11 versus 0.66±0.69 mL/min/g, respectively, P=0.02). However, patients undergoing bypass grafting had a more advanced stage of coronary artery disease and more incomplete revascularizations. Conclusion: Successful coronary revascularization has a significant and positive impact on absolute myocardial perfusion as assessed by serial quantitative [15O]H2O positron emission tomography. Notably, improvement of FFR after PCI was directly related to the increase in hyperemic MBF.

AUTOMATIC SPECT ANALYSIS COMPARED TO EXPERT VISUAL SCORING FOR THE DETECTION OF CORONARY ARTERY DISEASE

Background: Traditionally, the interpretation of myocardial perfusion imaging is based on visual analysis. A computer-based automated analysis might be a simple alternative obviating the need for extensive reading experience. Therefore, the aim of the present study is to compare the diagnostic

Impact of right ventricular side branch occlusion during percutaneous coronary intervention of chronic total occlusions on right ventricular function

OBJECTIVE To determine the impact of right ventricular side branch (RVB) occlusion, during percutaneous coronary interventions (PCIs) of chronic total occlusions (CTOs) of the right coronary artery (RCA), on right ventricular (RV) function. BACKGROUND Developments in PCI techniques have expanded PCI CTO feasibility. However, the utilization of dissection and reentry techniques and extensive stent implantation increases the risk of coronary side branch occlusion. METHODS Fifty-four patients (80% male, 63±10years) evaluated with cardiac magnetic resonance imaging (CMR) prior and three months after successful PCI CTO RCA (median: 99days, IQR: 92-105days) were included. Right ventricular end-diastolic volume (RVEDV), end-systolic volume (RVESV), and ejection fraction (RVEF) were quantified on CMR images. Occurrence of RVB occlusion and/or RVB recruitment was assessed using procedural angiograms. RESULTS RVB occlusion was observed in 12 patients (22%), while RVB recruitment occurred in seven patients (13%). Overall, RVEF was comparable between baseline and follow-up (53.8±5.8 vs. 53.9±5.8%, p=0.95). RVB occlusion was not associated with a significant change in RVEDV or RVEF (156.9±36.3 vs. 162.1±35.5mL, p=0.30 and 54.2±3.9 vs. 52.7±4.4%, p=0.19, respectively); however a trend was observed for an increase of RVESV (72.5±20.0 vs. 77.4±20.7mL, p=0.05) at follow-up. RVB recruitment did not result in a significant improvement of RVEF (55.4±4.6 vs. 56.1±5.3%, p=0.75). CONCLUSION RVB occlusion was not associated with a significant decreased RVEF at follow-up, although the results suggested a limited increase of RVESV.