Cross-Sectional and Longitudinal Positive Remodeling After Subintimal Drug-Eluting Stent Implantation

Impact of Selection Preference on Longer-Term Outcomes between Bioresorbable Vascular Scaffold versus Everolimus-Eluting Stent for True Lumen Tracking-Recanalized Chronic Total Occlusion

Creation of sizable subintima during intervention for chronic total occlusions (CTO) could lead to the key selection preference of metallic stents rather than bioresorbable vascular scaffolds (BVS) and then possibly deviate the outcome comparisons in real-world studies. By including recanalized CTO with true lumen tracking, we tested if any selection preference remained and compared the outcomes between everolimus-eluting stent (EES) and BVS implantation.Among 211 consecutive CTO interventions with true lumen tracking from August 2014 to April 2018 when BVS was available, we compared the clinical and interventional features between 28 patients with BVS and 77 patients with EES implantation. With propensity score matching and a median follow-up of 50.5 (37.3-60.3) months, we further assessed 25 patients with BVS and 25 with EES for target vessel failure (TVF: cardiac death, target vessel myocardial infarction, and target lesion revascularization).Multivariate analyses showed that BVS was still favored in the presence of LAD CTO (odds ratio (OR) = 3.4, 95% confidence interval (CI) = 1.0-11.7) and an average scaffold/stent size ≥ 3 mm (OR = 10.5, 95% CI = 3.0-37.3). EES was preferred for lesions with a J-CTO score ≥ 3 (OR = 19.3, 95% CI = 3.4-110.8) and multivessel intervention necessary at index procedure (OR = 11.3, 95% CI = 1.9-67.3). With matched comparisons, the TVF-free survival of EES was better than that of BVS for CTO recanalization (P = 0.049 by log-rank test) at long-term follow-up.Even with true lumen tracking techniques, selection bias remained substantial when determining either device for CTO implantation. The matched comparison of outcomes suggested the unfavorable longer-term impacts of the first generation of BVS on CTO lesions.

The impact of dissection and re-entry versus wire escalation techniques on long-term clinical outcomes in patients with chronic total occlusion lesions following percutaneous coronary intervention: An updated meta-analysis

BACKGROUND

The meta-analysis was performed to evaluate the effect of dissection and re-entry (DR) vs. wire escalation (WE) techniques on long-term clinical outcomes in patients with chronic total occlusion (CTO) lesions undergoing percutaneous coronary intervention.

METHODS

Studies were searched in electronic databases from inception to September, 2019. Results were pooled using random effects model and fixed effects model and are presented as risk ratios (RR) with 95% confidence intervals (CI).

RESULTS

Pooled analyses revealed that patients with DR techniques had overall higher complexity CTO lesions than patients with WE techniques and required a greater number of stents and a greater mean stent length. The "extensive" DR techniques may have a higher incidence of target vessel revascularization (TVR) (RR = 2.30, 95% CI: 1.77-2.98), in-stent restenosis (RR = 1.71, 95% CI: 1.30-2.23), in-stent reocclusion (RR = 1.86, 95% CI: 1.03-3.3) and death/myocardial infarction/TVR (RR = 2.10, 95% CI: 1.71-2.58), when compared with WE techniques, during the long-term follow-up. However, "limited" DR techniques result in more promising outcomes, and are comparable to conventional WE techniques.

CONCLUSIONS

Dissection and re-entry techniques were associated with increased risk of long-term negative clinical events, especially "extensive" DR techniques. However, "limited" DR techniques resulted in good long-term outcomes, comparable to WE techniques.

Clinical and angiographic outcomes of true vs. false lumen stenting of coronary chronic total occlusions: Insights from intravascular ultrasound

OBJECTIVES

The clinical implications of subintimal stenting (SS) of the recanalized chronic total occlusion (CTO) segment have not been characterized. We evaluated the in-hospital and the long-term clinical and angiographic outcomes of drug-eluting stents (DESs) deployed in true vs. false lumen of successfully recanalized CTO.

METHODS AND RESULTS

Two independent reviewers analyzed the intravascular ultrasound (IVUS) images of 173 successfully recanalized CTO lesions (157 patients), between August 2011 and October 2012. After successful guidewire (GW) crossing, lesions were classified according to IVUS evaluation into two groups: (1) true lumen (TL) stenting group and (2) SS group; and compared with regards to in-hospital and long-term clinical outcomes. In 154 lesions, DESs were deployed in the TL; and in 19 (11%) lesions, DESs were deployed in the subintimal space (95% confidence interval: 6.3-15.6%). False GW tracking in the SS group resulted in increased rates of IVUS-detected dissection flaps (84% vs. 42.6%, P ≤ 0.001), intramural hematoma (32 vs. 11%, P = 0.01), and minor perforations 6/19 (31.6% vs. 8.4%, P = 0.002). At 1-year follow-up, both groups had similar cumulative rates of binary restenosis and target lesion revascularization (P = 0.73 and P = 0.97, respectively). Six patients (4.6%, 6/129 patients) in the TL group and none in the subintimal group died at 1 year.

CONCLUSIONS

Acknowledging some limitations, our observations may suggest that, subintimal stent deployment in a recanalized CTO segments, using second generation DES and IVUS guidance, might have a comparable success rate and long-term angiographic and clinical outcomes as TL stenting.

Left Anterior Descending Artery Myocardial Bridging: A Clinical Approach

A myocardial bridge (MB) is the term for the muscle overlying the intramyocardial segment of the epicardial coronary artery (referred to as a tunneled artery). Although MBs can be found in any epicardial artery, most of them involve the left anterior descending artery. These congenital coronary anomalies have long been recognized anatomically, and are traditionally considered a benign condition; however, the association between myocardial ischemia and MBs has increased their clinical relevance. This review summarizes the prevalence, pathophysiology, and diagnostic findings, including morphological, functional assessment, and treatment of patients with MB involving the left anterior descending artery, suggesting a pragmatic clinical approach to this entity.

Serial Intravascular Ultrasound Findings After Treatment of Chronic Total Occlusions Using Drug-Eluting Stents

Morphologic changes after chronic total occlusion (CTO) treatment with drug-eluting stents (DESs) have not been assessed in detail. Our aim was to use both baseline and follow-up intravascular ultrasound studies to evaluate the morphologic changes and, especially, the changes in distal vessel size and the effect of subintimal stenting after treatment of CTOs with DES. We analyzed serial follow-up intravascular ultrasound (baseline and follow-up at 9 ± 2 months) after DES implantation into 40 CTOs. Overall, 33 CTOs were treated by the anterograde approach; and 7 were treated by the retrograde approach. Minimum lumen cross-sectional area (CSA) trended toward a decrease from baseline to follow-up (4.8 ± 1.7 vs 4.5 ± 1.7 mm(2), p = 0.10), although the minimum stent CSA (4.8 ± 1.7 vs 4.9 ± 1.7 mm(2), p = 0.26) did not change. The distal reference, but not the proximal reference lumen CSA, increased significantly at follow-up (3.8 ± 2.0 to 5.1 ± 2.3 mm(2), p = 0.0004). Late-acquired stent malapposition was seen in 17 patients (42.5%). In 8 CTOs (20%), a part of the stent was implanted into a subintimal space; in these 8 patients, maximum percent neointimal hyperplasia and minimum lumen area was similar in the subintimal segment compared with the adjacent intraplaque segment. The frequency of late-acquired stent malapposition was similar. In conclusion, after CTO treatment with DES, distal vessel enlargement was detected. Subintimal stenting after recanalization of CTO was not inferior compared with stenting within the plaque in terms of long-term morphologic impact.

Stent fracture and longitudinal compression detected on coronary CT angiography in the first- and new-generation drug-eluting stents

To evaluated prevalence and clinical implication of stent fracture and longitudinal compression in first- and new-generation drug-eluting stents (DES) using coronary computed tomography angiography (CCTA). The incidence of stent fracture and longitudinal compression were compared between first- and new-generation DES in 374 patients who underwent coronary stenting using DES and follow-up CCTA due to recurrent angina. 235 and 139 patients received 322 first- and 213 new-generation DES, respectively. The crude per-stent incidence of longitudinal compression (6.1 vs. 0.3 %, p < 0.001) was higher after new- than first-generation DES implantation using CCTA and the incidence of stent fracture (11.3 vs. 8.1 %, p = 0.23) was comparable. On follow-up coronary angiography for 347 stents, stent fracture (3.2 %) and longitudinal compression (0.9 %) were less detected than those on CCTA. Ostial stenting was a risk factor of longitudinal compression (p < 0.001). Stent fracture was associated with younger patients (p = 0.03), longer stent (p = 0.010), and excessively tortuous lesions (p = 0.001). The presence of stent fracture or longitudinal compression was not associated with poor clinical outcomes. The longitudinal compression more frequently occurred after new-generation DES implantation. The stent fracture was comparable between two DES. However, the occurrence of such mechanical deformities did not translate into a poor clinical outcome.

Intravascular ultrasound findings of stent fractures in patients with Sirolimus- and Paclitaxel-eluting stents

We compared intravascular ultrasound (IVUS) findings of fractures of sirolimus-eluting stents (SESs) versus paclitaxel-eluting stents (PESs). IVUS findings in 6 PES fractures (all in the right coronary artery) in 6 patients from a clinical trial cohort were compared to 14 SES fractures (8 in the right coronary artery, 2 in the left anterior descending coronary artery, and 4 in the left circumflex coronary artery) in 13 patients from our institutional cohort. Comparing PES fractures to SES fractures, IVUS analysis showed (1) similar frequency of complete stent fracture (1 of 6, 17%, vs 3 of 14, 21%, p >0.99), (2) similar frequency of fracture adjacent to calcified plaque or stent metal overlap (5 of 6, 86%, vs 14 of 14, 100%, p = 0.99), (3) more frequent complete malalignment of proximal and distal fragments in PES strut fractures compared to SES fractures (5 of 6, 83%, vs 1 of 14, 7%, p = 0.002), (4) similar stent lengths (45.2 mm, 23.8 to 50.7, vs 39.3 mm, 22.6 to 73.4, p >0.99), (5) similar fracture lengths (0.5 mm, 0.4 to 0.7, vs 0.7 mm, 0.6 to 1.0, p = 0.14), and (6) larger reference external elastic membrane area (15.0 mm(2), 13.5 to 18.0, vs 10.4 mm(2), 6.8 to 13.6, p = 0.01). In conclusion, malalignment of proximal and distal stent fragments more often occurred in PES fractures compared to SES fractures; otherwise the IVUS features of PES and SES fractures were similar.