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Covered stents offer an effective bail-out strategy in vessel perforations, are an alternative to surgery for the exclusion of coronary aneurysms, and have a potential role in the treatment of friable embolisation-prone plaques. The aim of this manuscript is to offer an overview of currently available platforms and to report results obtained in prior studies.

Background: The effect of optical coherence tomography (OCT) guidance on the implantation strategy during all phases of percutaneous coronary intervention (PCI) with bioresorbable vascular scaffolds (BVSs) in a real-world scenario has been poorly investigated., Methods: Consecutive patients undergoing BVS implantation at our institution were included in this registry. Frequency-domain OCT pullbacks were performed at the operator's discretion during all phases of BVS implantation procedures to optimize preparation of lesions, confirm BVS size, and optimize expansion and apposition of scaffolds., Results: Between September 2012 and July 2015, 203 BVSs were implanted in 101 consecutive patients at our institution (2.01 BVSs/patient). In 66 patients, the procedure was performed under OCT guidance. In the OCT subgroup, 66 (77.6%) of the 85 treated lesions were complex (B2/C AHA/ACC type). Overall, 147 OCT pullbacks were performed and 72/147 (49.0%) pullbacks indicated the need for changing strategy. After angiography-only-guided optimisation of BVS in 27 (31.8%) lesions, an OCT examination prompted performance of a second post-expansion. This resulted in an increase in the minimal scaffold area (5.5 to 6.3mm(2), p=0.004) and a decrease in the incomplete scaffold apposition area (1.1 to 0.6mm(2), p=0.082), with no new stent fractures. When the population was divided according to the time of BVS implantation, an initial learning adaptation became evident, with the number of OCT-guided changes in strategy significantly decreasing between the initial and final time periods (p=0.017)., Conclusions: OCT guidance for BVS implantation significantly affects the procedural strategy, with favourable effects on acute results and the learning curve., (Copyright © 2016. Published by Elsevier Ireland Ltd.)

Objectives: Optical coherence tomography (OCT) was used to investigate integrity and expansion of bioresorbable drug-eluting scaffolds (BVS) after high-pressure postdilation (HPPD)., Background: Because of concerns about the risk of BVS damage, postdilation was not recommended and applied in the existing randomized studies and most registries. Recent real world data suggest incomplete BVS expansion cause higher rates of thrombosis. In vivo confirmation of the safety of high pressure postdilation is of paramount importance., Methods: Data from final OCT examination of consecutive implanted BVS, postdilated with noncompliant (NC) balloons at pressure ≥24 atm were analyzed. The following stent performance indices were assessed with OCT: mean and minimal lumen and scaffold area, residual area stenosis (RAS), incomplete strut apposition (ISA), tissue prolapse, eccentricity index (EI), symmetry index (SI), strut fractures, and edge dissections., Result: Twenty-two BVS postdilated at high pressure were analyzed. The average maximal postdilation balloon inflation (maxPD) was 28 ± 3 atm. High pressure OPN NC Balloon (SIS Medical AG, Winterthur Switzerland) was used in 41% of postdilations with a maximal PD of 30 ± 4.7 atm. Final mean and minimal lumen area were 6.8 ± 1.4 and 5.5 ± 1.4 mm(2) , respectively. OCT showed low percentage of RAS (16 ± 9.6%), and low percentage of ISA (1.8 ± 2.4%). Mean EI was 0.86 ± 0.02 and SI 0.35 ± 0.14. OCT analysis showed one edge dissection and no scaffold fractures., Conclusions: BVS deployment optimization using HPPD does not cause BVS disruption and is associated with a good BVS expansion, low rate of strut malapposition and edge dissections., (© 2015 Wiley Periodicals, Inc.)

Background: The use of covered stent grafts during percutaneous coronary intervention (PCI) is a life saving solution to seal acute iatrogenic vessel rupture. However, the presence of an impenetrable mechanical barrier is also appealing during treatment of friable coronary plaques but the synthetic PTFE-membrane that might trigger excessive neointimal proliferation has limited its elective-use. Pericardium tissue may offer an appealing "natural" alternative. Aim of our study is to report the consecutive 5-year single center experience with the use of pericardium-covered stents (PCS) (ITGI-Medical, Israel) in a variety of emergency and elective applications., Methods: Nineteen consecutive patients undergoing implantation of PCS at the Royal Brompton in the last 5-years. Reasons for PCS implantation included treatment of degenerated vein grafts, large coronary aneurysms, and acute iatrogenic vessel rupture., Results: Angiographic success, defined as the ability of the device to be deployed in the indexed lesion with no contrast extravasation with residual angiographic stenosis <30% and a final thrombolysis in myocardial infarction (TIMI)-3 flow was achieved in all cases. Procedural success, defined as the achievement of angiographic success without any major adverse cardiovascular event (MACE) was achieved in 94.7% of patients. In-stent restenosis (ISR) was observed in 26.3% and all patients underwent successful target vessel revascularization with DES (mean time to restenosis 9.0 ± 4.0 months). At a mean follow-up of 32.5 ± 23.3 months no acute or late stent thrombosis was observed., Conclusion: PCSs were effective in the treatment of friable embolization-prone coronary plaques, sealing of acute iatrogenic vessel rupture and exclusion of large aneurysms with no thrombosis but high target lesion revascularization., (© 2015 Wiley Periodicals, Inc.)

Background: Although disturbed flow is thought to play a central role in the development of advanced coronary atherosclerotic plaques, no causal relationship has been established. We evaluated whether inducing disturbed flow would cause the development of advanced coronary plaques, including thin cap fibroatheroma., Methods and Results: D374Y-PCSK9 hypercholesterolemic minipigs (n=5) were instrumented with an intracoronary shear-modifying stent (SMS). Frequency-domain optical coherence tomography was obtained at baseline, immediately poststent, 19 weeks, and 34 weeks, and used to compute shear stress metrics of disturbed flow. At 34 weeks, plaque type was assessed within serially collected histological sections and coregistered to the distribution of each shear metric. The SMS caused a flow-limiting stenosis, and blood flow exiting the SMS caused regions of increased shear stress on the outer curvature and large regions of low and multidirectional shear stress on the inner curvature of the vessel. As a result, plaque burden was ≈3-fold higher downstream of the SMS than both upstream of the SMS and in the control artery (P<0.001). Advanced plaques were also primarily observed downstream of the SMS, in locations initially exposed to both low (P<0.002) and multidirectional (P<0.002) shear stress. Thin cap fibroatheroma regions demonstrated significantly lower shear stress that persisted over the duration of the study in comparison with other plaque types (P<0.005)., Conclusions: These data support a causal role for lowered and multidirectional shear stress in the initiation of advanced coronary atherosclerotic plaques. Persistently lowered shear stress appears to be the principal flow disturbance needed for the formation of thin cap fibroatheroma., (© 2015 American Heart Association, Inc.)

Radiofrequency (RF) ablation of accessory bypass tracts associated with the Wolff-Parkinson-White (WPW) syndrome has become the treatment of choice for many arrhythmias. Complications are unusual and acute coronary artery occlusion is very rare. We here present a 38-year-old male patient with an acute occlusion of proximal left anterior descending (LAD) coronary artery after RF ablation of a left free wall accessory pathway. An interesting feature is the site of the coronary artery occlusion which is remote from the RF application site. The occlusion was successfully treated with the placement of an intracoronary stent.

Background: The aim of this study is to evaluate heart rate recovery (HRR) and association between coronary flow rate and HRR in patients with metabolic syndrome (MS) who had morphologically normal coronary angiogram., Methods: Study population included 43 patients with MS and 37 control subjects without MS. All patients were selected from individuals who had recently undergone coronary angiography in our hospital and were diagnosed as having angiographically normal coronary arteries. Exercise stress test results obtained prior to coronary angiography were evaluated for calculating HRR and other parameters. In addition, coronary flow was objectively evaluated for each major coronary artery in each subject using TIMI frame count method., Results: All HRR values calculated were detected significantly lower in MS group compared to controls (HRR first: 32 ± 9 vs. 37 ± 10; p = 0.01, second: 46 ± 11 vs. 52 ± 11; p = 0.03, third: 51 ± 12 vs. 59 ± 12; p = 0.00, fourth: 54 ± 13 vs. 61 ± 2; p = 0.02). TIMI frame counts for each major epicardial coronary artery and mean TIMI frame count were also found to be significantly higher in MS group compared to controls (left anterior descending artery:51 ± 24 vs. 39 ± 15; p = 0.009, left circumflex artery: 32 ± 11 vs. 24 ± 7; p = 0.001, right coronary artery: 33 ± 14 vs. 24 ± 10; p = 0.003, mean TIMI frame count: 38 ± 15 vs. 29 ± 9;p = 0.002). Additionally, significant negative correlations were also detected between HRR first minute and coronary TIMI frame count values in patients with MS. None of MS parameters did not affect HRR values, however mean TIMI frame count independently associated with HRR first minute (p = 0.04) in patients with MS., Conclusions: Impaired coronary blood flow occurring in MS might be a clue of autonomic dysfunction in addition to previously known endothelial dysfunction.

Coronary artery perforation (CAP) is a rare but feared complication of percutaneous coronary intervention. With the advent of new devices and technologies, interventionalists attempt more complex lesions, including more calcified or tortuous vessels and chronic total occlusions, which increases the incidence of CAP. A short literature review, in addition to four cases of CAP, is presented in this report., (Copyright © 2013 Sociedade Portuguesa de Cardiologia. Published by Elsevier España. All rights reserved.)