The therapeutic effects of excimer laser coronary atherectomy therapy for in-stent restenosis chronic total occlusions

Objectives To evaluate the safety and efficacy of excimer laser coronary atherectomy (ELCA) in patients with in-stent restenosis chronic total occlusions (ISR CTOs). Background ISR CTOs are a challenge in percutaneous coronary intervention (PCI). Although they can be treated by ELCA, limited data are available on the effects of ELCA treatment in these patients. Methods Fifty-nine consecutive patients underwent PCI for ISR CTOs at Beijing Hospital between December 2017 and September 2020. According to whether or not ELCA was performed, they were divided into two groups. Quantitative coronary angiography (QCA) analyses were performed routinely, including measurement of the minimal lumen diameter and calculation of the percentage diameter stenosis. The procedural success rate, the frequency of peri-procedural complications, and the incidence rates of major adverse cardiac events (MACEs) over nine months were assessed. The primary endpoint in the study was the percentage diameter stenosis. Results Procedure success was achieved in most patients in both groups (75.9%). Patients in the ELCA group exhibited a lower percentage diameter stenosis (24.5 ± 9.09 vs. 35.1 ± 18.6, p = 0.048) and a larger minimal lumen diameter (2.36 ± 0.29 mm vs. 1.78 ± 0.64 mm, p < 0.001) than those in the control group and the 9-month incidence rates of MACEs did not differ (9.5% vs 15.8%, p = 0.699). Conclusions This study demonstrated that ELCA may be a safe and effective technique in the treatment of ISR CTOs, and the use of ELCA can achieve good immediate angiographic results, as measured by QCA, without increasing peri-procedural complications or the incidence rates of 9-month MACEs.

Hemodynamic Versus Anatomic Assessment of Symptomatic Atherosclerotic Middle Cerebral Artery Stenosis: the Relationship Between Pressure Wire Translesional Gradient and Angiographic Lesion Geometry

Background: Intracranial cerebral atherosclerosis (ICAS) is a leading etiology of ischemic stroke. The diagnosis and assessment of intracranial stenosis are shifting from anatomic to hemodynamic for better risk stratification. However, the relationships between lesion geometry and translesional pressure gradient have not been clearly elucidated.Methods: Patients with symptomatic unifocal M1 middle cerebral artery (M1-MCA) stenosis were consecutively recruited. The translesional pressure gradient was measured with a pressure wire and was recorded as both mean distal/proximal pressure ratios (Pd/Pa) and translesional pressure difference (Pa–Pd). Lesion geometry measured on angiography was recorded as diameter stenosis, minimal lumen diameter, and lesion length. The correlations between pressure-derived and angiography-derived indices were then analyzed.Results: Forty-three patients were analyzed. A negative correlation was found between Pd/Pa and diameter stenosis (r = −0.371; p = 0.014) and between Pa – Pd and minimal lumen diameter (r = −0.507; p = 0.001). A positive correlation was found between Pd/Pa and minimal lumen diameter (r = 0.411; p = 0.006) and between Pa – Pd and diameter stenosis (r = 0.466; p = 0.002).Conclusions: In a highly selected ICAS subgroup, geometric indices derived from angiography correlate significantly with translesional pressure gradient indices. However, the correlation strength is weak-to-moderate, which implies that anatomic assessment could only partly reflect hemodynamic status. Translesional pressure gradient measured by pressure wire may serve as a more predictive marker of ICAS severity. More factors need to be identified in further studies.

Double kissing inflation outside the stent secures the patency of small side branch without rewiring

Background The jailed balloon technique is widely used for coronary bifurcation lesions, but a residual risk of SB occlusion remains, necessitating SB rewiring and further interventions, including balloon inflation or stenting, which may result in failure and SB loss. This study introduced a novel modified technique of small side branch (SB) protection, namely, double kissing inflation outside the stent (DKo) technique, for coronary bifurcations without the need for SB rewiring. Methods We performed the DKo technique in consecutive patients in our center from 1/2019 to 12/2019. The procedure was as follows. We inserted a guide wire into both branches followed by proper preparation. The SB balloon was simultaneously inflated with main vessel (MV) stenting. The SB balloon remained in situ until it was kissing inflated with postdilation of the bifurcation core, which is different from traditional strategies. The proximal optimization technique was performed with a short noncompliant balloon strictly not exceeding the bifurcation. Rates of SB loss and in-hospital outcomes were evaluated. Results The technique was successfully performed in all 117 enrolled patients without any rewiring or SB loss. The mean lesion lengths of the MV and SB were 38.3 ± 19.9 mm and 11.7 ± 7.1 mm, respectively. On average, 1.5 ± 0.6 stents were used per patient, while the mean pressure of the SB balloon was 7.4 ± 3.1 atm. DKo achieved excellent procedural success in the proximal and distal MVs: increased minimal lumen diameter (0.64 ± 0.58 mm to 3.05 ± 0.38 mm, p < 0.001; 0.57 ± 0.63 mm to 2.67 ± 0.35 mm, p < 0.001) and low residual stenosis (11.4 ± 3.4%; 7.2 ± 4.6%). DKo secured the patency of the SB without any rewiring and improved the SB stenosis with minimal lumen diameter (0.59 ± 0.48 mm to 1.20 ± 0.42 mm, p < 0.001) and stenosis (71.9 ± 19.4% to 42.2 ± 14.0%, p < 0.001). No MACE was noted in the hospital. Conclusions DKo for bifurcation lesions was shown to be acceptable with high procedural success and excellent SB protection.

Impact of Age on the Functional Evaluation of Intermediate Coronary Stenoses With Instantaneous Wave-Free Ratio and Fractional Flow Reserve

The optimal strategy for assessing the ischemic significance of intermediate coronary stenoses with adenosine-induced fractional flow reserve (FFR) and instantaneous wave-free ratio (iFR) is still debated. Few studies have previously assessed the impact of age on FFR and iFR, which was the aim of our study. Patients undergoing FFR and iFR evaluation for intermediate (40%-70%) coronary lesions were included and divided according to age. Fractional flow reserve was performed by intracoronary boluses of adenosine (60-1440 μg). Instantaneous wave-free ratio was automatically calculated. Among 148 patients undergoing FFR measurement of 166 lesions, 45.3% were ≥70 years. Elderly patients had higher minimal lumen diameter ( P = .03). We also observed a linear relationship between iFR and FFR independently of age. Fractional flow reserve values were higher in the elderly patients, whereas iFR was not related to age. A total of 33 lesions had a positive iFR with no difference for age (17.3% vs 22%, P = .56), while FFR <0.80 was more infrequent in the elderly patients (17.1% vs 34.8%, P = .02). In intermediate coronary stenoses, iFR and FFR correlation is unaffected by age. Fractional flow reserve is higher in the elderly patients, whereas iFR is less affected by age. Future large-scale studies are needed to define whether iFR should be the preferred choice in elderly patients.

The Functional Severity Assessment of Coronary Stenosis Using Coronary Computed Tomography Angiography-Based Myocardial Mass at Risk and Minimal Lumen Diameter

Background. We investigated whether or not the addition of myocardial mass at risk (MMAR) to quantitative coronary angiography was useful for diagnosing functionally significant coronary stenosis in the daily practice. Methods. We retrospectively enrolled 111 consecutive patients with 149 lesions who underwent clinically indicated coronary computed tomography angiography and subsequent elective coronary angiography with fractional flow reserve (FFR) measurement. MMAR was calculated using a workstation-based software program with ordinary thin slice images acquired for the computed tomography, and the minimal lumen diameter (MLD) and the diameter stenosis were measured with quantitative coronary angiography. Results. The MLD and MMAR were significantly correlated with the FFR, and the MMAR-to-MLD ratio (MMAR/MLD) showed a good correlation. The area under the receiver operating characteristic curve (AUC) of MMAR/MLD for FFR ≤ 0.8 was 0.746, and the sensitivity, specificity, positive predictive value, and negative predictive value were 60%, 83%, 68%, and 77%, respectively, at a cut-off value of 29.5 ml/mm. The addition of MMAR/MLD to diameter stenosis thus made it possible to further discriminate lesions with FFR ≤ 0.8 (AUC = 0.750). For the proximal left coronary artery lesions, in particular, MMAR/MLD showed a better correlation with the FFR, and the AUC of MMAR/MLD for FFR ≤ 0.8 was 0.919 at a cut-off value of 31.7 ml/mm. Conclusions. The index of MMAR/MLD correlated well with the physiological severity of coronary stenosis and showed good accuracy for detecting functional significance. The MMAR/MLD might be a useful parameter to consider when deciding the indication for revascularization.

Abstract 11491: Differences in the Development of Restenosis Over Time for Various Drug-Eluting Stents

Objective: This study aims to compare the efficacy of sirolimus-eluting stents (SES), paclitaxel-eluting stents (PES), zotarolimus-eluting stents (ZES), and everolimus eluting stents (EES) via sequential angiographic follow-up and to reveal the development of restenosis over time. Methods: Patients were randomized to receive SES, PES, ZES, or EES, and follow-up angiography was performed at 6, 12 and 24months after percutaneous coronary intervention. Results: The baseline clinical characteristics of the patients and the coronary lesions are shown in (Table 1). In all groups, mean minimal lumen diameter decreased slightly during the 2-year period after the procedure (Figure 1). Compared with the SES group, the PES and the ZES groups showed greater late loss (LL) within 1 year. However, the SES group showed significantly greater LL compared with the other drug-eluting stents (DES) between 1 and 2 years (Figure 2). Conclusion: Serial angiographic analysis revealed differences in the rate of restenosis development over time for various DES. As DES are comprised of many components (metallic platform, alloy, drug and polymer), the progression of LL can be complex and affected by different factors.