Contemporary treatment of patients with chronic total occlusion: critical appraisal of different state-of-the-art techniques and devices

Mother-child technique using a novel 4 Fr inner catheter

AIMS

The aim of this study was to assess the efficacy of the mother and child technique using a 4 Fr inner catheter in coronary angioplasty following the failure of conventional techniques.

METHODS AND RESULTS

We identified cases in which a 4 Fr inner catheter had been used to facilitate stent delivery following the failure of conventional techniques. Stent delivery using a 4 Fr inner catheter was performed in 30 cases and was successful in 29 cases. Nineteen cases for RCA, six cases for LAD and five cases for LCx were examined. Direct engagement of a 4 Fr inner catheter was accomplished in eight cases. In the remaining patients, deep engagement of a 4 Fr inner catheter was accomplished with the anchor technique and/or distal balloon deflation technique. Proximal stent delivery followed by distal stent deployment was performed in seven cases by using the distal balloon deflation technique in multiple stent deployment. There were no complications related to deep intubation of a 4 Fr inner catheter.

CONCLUSIONS

The use of a 4 Fr inner catheter is safe and highly effective for aiding stent delivery. The anchor technique and/or distal balloon deflation technique could be required for deep engagement of a 4 Fr inner catheter.

Efficacy of mother-child-grandchild technique: 4F and 5F inner catheters through mother guide catheter

Stent delivery failure to the distal lesion was still encountered even after the introduction of mother-child technique using a 5F or 4F child catheter. A 5F inner catheter with a length of 112cm, and a 4F inner catheter with a length of 122cm enabled a novel mother-child-grandchild technique. In in vitro experiments, not only was backup support increased, but superior trackability could also be obtained with the mother-child-grandchild technique, over the mother-child technique. We describe the clinical data using this novel mother-child-grandchild technique to deliver a stent to the severely bended and/or calcified distal lesion.

Guidewires used in first intentional single wiring strategy for chronic total occlusions of the left anterior descending coronary artery

Background:

Percutaneous coronary intervention (PCI) for chronic total occlusion (CTO) of the left anterior descending (LAD) specifically is associated with improved long-term 5 year survival as compared to PCI failure. The procedure is associated with usage of different types of dedicated guidewires by simple or complex techniques aiming to reopen the occluded artery.

Aim:

To describe types and outcome of guidewires used in LAD-CTO utilizing a first intentional single wiring simple strategy.

Methods:

A single center prospective registry for all consecutive patients with a PCI attempt to a native LAD CTO. The initial strategy for lesion crossing was Single wiring.

Results:

A total of 30 patients with LAD CTO lesions (100%), were recorded. Mean age was 71.6 + 15 years, 77% were Males, risk factors Hypertension in 63%, Diabetes 27%, Dyslipidemia 57%, smoking 40%, hereditary in 13% of patients. Isolated guidewire (GW) success rate was very high 93%. Single wiring was the prevailing technique used in 97% of successfull lesions (83% of total cases) while only 3% were by multiple wiring techniques. Successful single antegrade wiring represented 63% with a GW success rate of 92% of cases. Successful single retrograde wiring represented 13% with a GW success rate of 67%. Successful Crossing GW types in our patients were 44% Soft Tapered GWs; fielder XT (44%), 36% were Soft Non Tapered Pilot 50 (28%), whisper (8%), while 16% were Stiff Non tapered GWs; Miracle 12 (8%), Miracle 6 (4%), Miracle 3 (4%), and 4% were Stiff Tapered GWs; Progress 200 (4%).

Conclusions:

Single wiring as an initial strategy in PCI for LAD-CTO lesions has a high success rate and is associated with a 44% majority of Soft Tapered GWs, 36% Soft Non Tapered, 16% Stiff Non tapered GWs, and 4% Stiff Tapered GWs.

Radial approach and single wiring as first intentional strategies in chronic total occlusions of the left anterior descending coronary artery

BACKGROUND

Percutaneous coronary intervention (PCI) for chronic total occlusion (CTO) of the left anterior descending coronary artery (LAD) specifically is associated with improved long-term 5 years survival as compared to PCI failure. Simpler PCI techniques may be successful and safer than complex techniques which are perceived to have high failure rates and technical complexity. We aimed to describe the safety and effectiveness of first intentional single wiring and radial approach in the treatment of patients with a CTO of the native LAD coronary artery at Toulouse Rangueil university hospitals.

PATIENTS AND METHODS

The study was a single center prospective registry. All patients showed evidence of myocardial viability in LAD territory. The operators' initial strategy was to start by a radial access as a first choice whenever feasible; if not, a femoral access was chosen. The initial strategy for lesion crossing in either antegrade or retrograde approaches was single wiring by lesion crossing using one guidewire (GW) as a simple technique.

RESULTS

A total of 30 patients with 30 LAD CTO lesions (100%) were recorded. Mean age was 71.6 + 15 years, 77% were males and 23% were females. The access route was radial 66% of the time and femoral 54% of the time and with double access for contralateral injection in 40% of the patients. Sheaths and catheters sizes 6F were used in 53% of the patients, and 7F in 73% of the patients. Overall lesion success rate was 83% of lesions. Single wiring was the prevailing technique used in 97% of successful lesions (83% of total cases), while only 3% were by multiple wiring techniques. Successful single antegrade wiring represented 63% of our total study cases with a GW success rate of 92% of cases. Successful single retrograde wiring represented 13% of our cases with a GW success rate of 67%. Q-wave myocardial infarction (MI), stent thrombosis, stroke, emergency coronary artery bypass graft (CABG), major bleeding, radiation dermatitis, cardiac tamponade or clinical perforation requiring any hemostatic maneuvers did not occur. There was a post-procedural Troponin rise of 3x normal levels in 30% of patients, and contrast induced nephropathy in 7%. Intra-aortic balloon counterpulsation (IABCP) was used in 3% of patients and cardiac death occurred in 3% of patients.

CONCLUSION

Single wiring and radial access as initial strategies in PCI for LAD-CTO lesions in either approaches antegrade or retrograde are associated with a high procedural success rate and an acceptable incidences of adverse events.

CRosser As First choice for crossing Totally occluded coronary arteries (CRAFT Registry): focus on conventional angiography and computed tomography angiography predictors of success

AIMS

We investigated the use of the CROSSER catheter, a CTO crossing device based upon high frequency mechanical vibration, as a first resort to treat patients with chronic total occlusions (CTO) while describing angiographic and computed tomography coronary angiography (CTCA) serving as predictors for success.

METHODS AND RESULTS

Eighty consecutive patients were enrolled in this prospective multicentre registry of patients treated for a CTO. For 76.3% of the patients, this was the first attempt to open the CTO. Overall success rate was 75%. By conventional coronary angiography, the length of the occlusion was 26.7±14.1 mm and there was a difference in successful vs. unsuccessful cases (24.5±13.9 and 32.8±13.1, p=0.02). The presence of angulation, as defined qualitatively, was more prevalent in failed cases (60.0% vs. 32.2%, p=0.03). The mean ratio CROSSER distance within the occlusion site and length of the occlusion showed a trend towards statistical significance in successful procedures (0.56±0.90 vs. 0.30±0.34, p=0.08). During hospitalisation, two patients had a non-fatal myocardial infarction. One patient experienced delayed onset of tamponade six hours postprocedure. At 30 days, two patients had PCI in a non-treated vessel and one patient had a transient ischaemic attack. Relation to the CROSSER catheter was inconclusive.

CONCLUSIONS

The success rate of the use of a dedicated-CTO device--the CROSSER catheter--as a first choice to open a chronic total occlusion was 75%. By multivariate analysis, in a subset of patients that were imaged with computed tomography coronary angiography, the absence of angulation was related with higher success rate.

Guidance of percutaneous coronary interventions by multidetector row computed tomography coronary angiography

Guidance of percutaneous coronary interventions (PCI) by intravascular ultrasound (IVUS) provides more precise information in terms of quantitative measurement and qualitative assessment of coronary artery disease (CAD) than does conventional angiography. Several studies have tested the efficacy of IVUS to guide stent implantation. However, the conflicting results have left behind a continued debate as to whether IVUS-guided PCI has an impact on clinical outcome and angiographic restenosis. IVUS and computed tomography coronary angiography (CTCA) share the ability to evaluate the lumen along with the vessel wall, enabling characterisation of proximal and distal reference segments. Nevertheless, IVUS imaging is expensive and usually precluded in severe stenoses. In the present article, we discuss the potential application of CTCA for the guidance of PCI, particularly of complex lesions such as chronic total occlusions (CTO) and bifurcations.

The feasibility and safety of applying the Magnetic Navigation System to manage chronically occluded vessels: a single centre experience

AIMS

Applying the Magnetic Navigation System (MNS) to manage chronic total occlusions (CTOs). The MNS precisely directs a magnetised guidewire in vivo through two permanent external magnets.

METHODS AND RESULTS

The first 43 consecutive MNS treated CTOs were retrospectively evaluated. Computed tomography coronary angiography (CTCA) co-integration with the MNS provided a virtual road map through the occlusion. Unsuccessful MNS cases were managed with bailout conventional guidewire techniques. Experienced CTO and MNS operators had unrestricted access to CTO devices and equipments. The MNS crossing success increased from 40% to 56% over 52 months and averaged 44.2% (19/43 patients). In 58.3% (14/24) of failed MNS cases the conventional wire approach was successful, giving an overall procedural success rate of 76.6%. Of those conventionally treated, two patients required pericardiocentesis. On average, 1.8 ± 0.9 stents (lengths 44.7 ± 21.4 mm and diameter 2.8 ± 0.4 mm) were implanted. Procedural times were lengthy (125.0 ± 35.3 min) requiring high fluoroscopy dosage (11980.2 ± 6457.9 Gy/cm2) and contrast media usage (388.8 ± 170.2 ml). Operators persevered less with magnetic wires (20.9 ± 12.4 min vs. 27.7 ± 24.4 min), and preferentially used the least stiff wire as first choice (53.5%). CTCA co-integration did not influence procedural outcome. As with conventional wires, higher magnetic wire successes occurred in low calcified lesions, those with a central stump and without bridging collaterals.

CONCLUSIONS

In unselected CTOs, the magnetic wires are safe and feasible. Current modest success rates with a high procedural bailout rate implicate the need for improved magnetic guidewire technology comparable to available sophisticated conventional CTO wires. Randomised studies are needed to clarify the value of magnetic guided recanalisation.

Use of the Proxis embolic protection device for guide anchoring and stent delivery during complex saphenous vein graft interventions

Optimal guide catheter engagement and an embolic protection strategy are crucial for successful saphenous vein graft (SVG) percutaneous coronary interventions. We describe three SVG cases during which the use of Proxis device not only provided embolic protection, but also served as a guide catheter anchor allowing distal stent delivery, after failed attempts using conventional techniques.

Successful use of the Heartrail III catheter as a stent delivery catheter following failure of conventional techniques

The Terumo "five in six" system involves insertion of an extra length, 5 Fr Terumo guide catheter (Heartrail, Terumo) into a standard 6 Fr guide catheter so that the tip protrudes beyond the 6 Fr guide. This system increases backup support and has been used successfully to advance balloon catheters across chronic total occlusions. We describe the use of this system to facilitate extra deep intubation, enabling distal stent delivery beyond proximal points of obstruction that had been unsuccessful using more conventional techniques.