Hybrid PCI strategy rules for complex CTO

 

PARIS – The so-called hybrid strategy is now the preferred approach to percutaneous coronary intervention (PCI) for chronic total occlusions (CTO), 12-month outcomes of the multicenter observational CONSISTENT CTO trial suggest, according to Simon J. Walsh, MD, an interventional cardiologist at Belfast Health and Social Care Trust.

Bruce Jancin/MDedge News

With use of the hybrid strategy, a CTO’s anatomic complexity is no longer a barrier to performing PCI with a success rate that by former standards would be considered astronomical, he said in presenting the CONSISTENT CTO results at the annual meeting of the European Association of Percutaneous Cardiovascular Interventions.

Indeed, the key take-home messages from CONSISTENT CTO were that technical success rates were dramatic at 98.6%, the target vessel failure rate at 12 months was impressively low at 5.24%, and quality of life scores showed clinically meaningful gains maintained through 1 year.

“Opening a CTO makes people better, reduces their symptom burden, and is something worth doing,” Dr. Walsh concluded.

That hasn’t always been the prevailing view. Historically, most interventional cardiologists had a pessimistic attitude regarding PCI for CTOs. The procedures had a low technical success rate, frequent complications, and lousy durability. Moreover, these subpar results came at a considerable price in terms of extensive radiation exposure and catheterization laboratory time. These various shortcomings became particularly prominent when traditional wire-based PCI strategies were applied to long, complex occlusions.

All that has changed as a result of improved stent technologies and procedural techniques, along with the development of the hybrid PCI algorithm by U.S. cardiologists. Using these tools, an interventionalist skilled in the hybrid strategy now selects cases on the basis of clinical indications, such as disabling angina, rather than on anatomic considerations. This point was emphatically brought home in CONSISTENT CTO (Conventional antegrade vs. sub-intimal synergy stenting in chronic total occlusions).

“This is the most complex set of treated CTO lesions ever investigated in this rigorous way,” according to Dr. Walsh.

This assertion was bolstered by the fact that the average Japan CTO (JCTO) score in the 210 study participants was 2.4, climbing to 2.9 in the 101 patients with dissection present. Further adding to the lesion complexity was the fact that roughly one in five subjects had a degenerated coronary artery graft in their target vessel. The average lesion length as measured at the study core lab was 29.1 mm. The impetus for the CONSISTENT CTO Study was a recognition that, even though a growing number of skilled operators are embracing the hybrid PCI strategy with heretofore unprecedented favorable results, there remains an evidence gap, with little in the way of long-term studies featuring rigorous follow-up. Participants in CONSISTENT CTO therefore underwent baseline formal quality of life assessment, repeated at 12 months of follow-up together with angiography and/or optical coherence tomography. Further follow-up is planned at 2, 3, and 5 years.

Of the 231 patients who consented to participate in the study, 210, or 90%, were able to have their CTO opened with a Synergy everolimus-eluting stent. Those 210 constituted the study population.

 

The hybrid algorithm-based PCI strategy utilizes an individual’s CTO anatomy to dictate the initial choice of approach. The goal is to pick the strategy that is most likely to achieve successful outcome efficiently, with minimal contrast and radiation doses for that particular type of CTO. The hybrid algorithm begins with dual-catheter injection and intravascular ultrasound aimed at determining whether four key anatomic features are present: an ambiguous proximal cap, a poor distal target, good interventional collaterals, and a major side branch at the distal cap.

If those four features are absent and the CTO lesion is less than 20-mm long, the algorithm dictates that the initial approach is antegrade wire escalation; if the lesion is 20 mm or more, the first approach is antegrade dissection reentry. However, if those anatomic features are present, the initial strategy is retrograde wire escalation if the lesion is less than 20 mm, and retrograde dissection reentry for longer lesions. When the initial approach fails, structured protocols dictate the selection of second and third approaches (JACC Cardiovasc Interv. 2012 Apr;5[4]:367-79).

The right coronary artery was the site of the CTO in 70% of study participants. Dual-catheter access was utilized in 79% of patients; only 10% had exclusively radial access. An average of 2.8 Synergy stents were deployed, with a whopping mean total stent length of 96.6 mm in the 48% of patients with dissection and 75.4 mm in those without. Mean procedure time was 122 minutes, with a fluoroscopy time of 44.6 minutes.

The primary efficacy endpoint was the rate of target vessel failure (TVF) at 12 months, defined as cardiac death, MI related to the target vessel, or any ischemia-driven revascularization of the target vessel. The rate was 5.24%.

“We were pleasantly surprised by that,” Dr. Walsh admitted.

Indeed, based upon studies of PCI for CTO published by other investigators, he and his colleagues had initially projected a 13% TVF rate, then bumped it up to 15% because of the high degree of lesion complexity.

Diabetes was the main predictor of target vessel revascularization.

At the time of the index PCI, 19% of patients were scheduled to return for an early optimization procedure within 3 months. This was arranged when operators anticipated significant positive remodeling would occur as the target vessel readjusted to blood flow or distal disease of borderline severity was noted beyond the CTO segment. These were not counted as adverse events. Half of the returnees underwent angiography and no further action was undertaken. The others underwent postdilation of their Synergy stents or new stenting of distal disease.

Complete revascularization of the target territory was achieved in 98.6% of patients. Key complications consisted of 5 perforations, 10 hematomas at vascular access sites, 2 cases of pericardiocentesis, and 4 instances of bleeding requiring transfusion.

The final successful CTO revascularization strategy was antegrade dissection reentry in 18% of patients, retrograde dissection reentry in 30%, antegrade wire escalation in 34%, and retrograde wire escalation in 18%. A switch from the initial algorithm-based strategy to a second strategy occurred in 41% of patients, and a third strategy was employed in 9%.

 

“I think the key message is you need to have more than one option to treat complicated disease. Half of patients had a switch in strategy,” Dr. Walsh observed.

Intravascular ultrasound (IVUS) adjudication in the central core lab showed a humbling rate of discordance between the operators’ impression of how their procedures were proceeding and what was really going on.

“There’s a bit of a mantra [that says] if you’re wiring stuff you’re always in the lumen, and if you’re using dissection techniques you’re always not in the lumen. In fact, that’s nonsense. You get it wrong one in six times. When you use IVUS adjudication to see if you’re outside the lumen or not, with wire-based retrograde escalation you’re out of the lumen and in the subintimal space 27% of the time. And with dissection strategies you’re wrong in about 15%,” according to the cardiologist.

He described the study participants as “extremely limited” at baseline as evidenced by their scores on the Seattle Angina Questionnaire Physical Limitation, Angina Stability, and Angina Frequency domains. At 12 months of follow-up, patients averaged 20- to 40-point improvements across all three domains.

One member of the discussion panel expressed a wish that the study had included a sham PCI arm. He raised the possibility that PCI had exerted an enormous placebo effect that could conceivably account for the substantial quality of life benefits documented in the study. But another panelist scoffed at this notion. This wasn’t a modest improvement in quality of life, nor was it measured after a mere 6 weeks, as was the case in the sham-controlled ORBITA trial.

“It’s really difficult to imagine a sham effect that persists out to a year,” he argued.

Dr. Walsh reported receiving research grants from and serving as a consultant to Boston Scientific, which funded the CONSISTENT CTO Study.

bjancin@mdedge.com

 

PARIS – The so-called hybrid strategy is now the preferred approach to percutaneous coronary intervention (PCI) for chronic total occlusions (CTO), 12-month outcomes of the multicenter observational CONSISTENT CTO trial suggest, according to Simon J. Walsh, MD, an interventional cardiologist at Belfast Health and Social Care Trust.

Bruce Jancin/MDedge News

With use of the hybrid strategy, a CTO’s anatomic complexity is no longer a barrier to performing PCI with a success rate that by former standards would be considered astronomical, he said in presenting the CONSISTENT CTO results at the annual meeting of the European Association of Percutaneous Cardiovascular Interventions.

Indeed, the key take-home messages from CONSISTENT CTO were that technical success rates were dramatic at 98.6%, the target vessel failure rate at 12 months was impressively low at 5.24%, and quality of life scores showed clinically meaningful gains maintained through 1 year.

“Opening a CTO makes people better, reduces their symptom burden, and is something worth doing,” Dr. Walsh concluded.

That hasn’t always been the prevailing view. Historically, most interventional cardiologists had a pessimistic attitude regarding PCI for CTOs. The procedures had a low technical success rate, frequent complications, and lousy durability. Moreover, these subpar results came at a considerable price in terms of extensive radiation exposure and catheterization laboratory time. These various shortcomings became particularly prominent when traditional wire-based PCI strategies were applied to long, complex occlusions.

All that has changed as a result of improved stent technologies and procedural techniques, along with the development of the hybrid PCI algorithm by U.S. cardiologists. Using these tools, an interventionalist skilled in the hybrid strategy now selects cases on the basis of clinical indications, such as disabling angina, rather than on anatomic considerations. This point was emphatically brought home in CONSISTENT CTO (Conventional antegrade vs. sub-intimal synergy stenting in chronic total occlusions).

“This is the most complex set of treated CTO lesions ever investigated in this rigorous way,” according to Dr. Walsh.

This assertion was bolstered by the fact that the average Japan CTO (JCTO) score in the 210 study participants was 2.4, climbing to 2.9 in the 101 patients with dissection present. Further adding to the lesion complexity was the fact that roughly one in five subjects had a degenerated coronary artery graft in their target vessel. The average lesion length as measured at the study core lab was 29.1 mm. The impetus for the CONSISTENT CTO Study was a recognition that, even though a growing number of skilled operators are embracing the hybrid PCI strategy with heretofore unprecedented favorable results, there remains an evidence gap, with little in the way of long-term studies featuring rigorous follow-up. Participants in CONSISTENT CTO therefore underwent baseline formal quality of life assessment, repeated at 12 months of follow-up together with angiography and/or optical coherence tomography. Further follow-up is planned at 2, 3, and 5 years.

Of the 231 patients who consented to participate in the study, 210, or 90%, were able to have their CTO opened with a Synergy everolimus-eluting stent. Those 210 constituted the study population.

 

The hybrid algorithm-based PCI strategy utilizes an individual’s CTO anatomy to dictate the initial choice of approach. The goal is to pick the strategy that is most likely to achieve successful outcome efficiently, with minimal contrast and radiation doses for that particular type of CTO. The hybrid algorithm begins with dual-catheter injection and intravascular ultrasound aimed at determining whether four key anatomic features are present: an ambiguous proximal cap, a poor distal target, good interventional collaterals, and a major side branch at the distal cap.

If those four features are absent and the CTO lesion is less than 20-mm long, the algorithm dictates that the initial approach is antegrade wire escalation; if the lesion is 20 mm or more, the first approach is antegrade dissection reentry. However, if those anatomic features are present, the initial strategy is retrograde wire escalation if the lesion is less than 20 mm, and retrograde dissection reentry for longer lesions. When the initial approach fails, structured protocols dictate the selection of second and third approaches (JACC Cardiovasc Interv. 2012 Apr;5[4]:367-79).

The right coronary artery was the site of the CTO in 70% of study participants. Dual-catheter access was utilized in 79% of patients; only 10% had exclusively radial access. An average of 2.8 Synergy stents were deployed, with a whopping mean total stent length of 96.6 mm in the 48% of patients with dissection and 75.4 mm in those without. Mean procedure time was 122 minutes, with a fluoroscopy time of 44.6 minutes.

The primary efficacy endpoint was the rate of target vessel failure (TVF) at 12 months, defined as cardiac death, MI related to the target vessel, or any ischemia-driven revascularization of the target vessel. The rate was 5.24%.

“We were pleasantly surprised by that,” Dr. Walsh admitted.

Indeed, based upon studies of PCI for CTO published by other investigators, he and his colleagues had initially projected a 13% TVF rate, then bumped it up to 15% because of the high degree of lesion complexity.

Diabetes was the main predictor of target vessel revascularization.

At the time of the index PCI, 19% of patients were scheduled to return for an early optimization procedure within 3 months. This was arranged when operators anticipated significant positive remodeling would occur as the target vessel readjusted to blood flow or distal disease of borderline severity was noted beyond the CTO segment. These were not counted as adverse events. Half of the returnees underwent angiography and no further action was undertaken. The others underwent postdilation of their Synergy stents or new stenting of distal disease.

Complete revascularization of the target territory was achieved in 98.6% of patients. Key complications consisted of 5 perforations, 10 hematomas at vascular access sites, 2 cases of pericardiocentesis, and 4 instances of bleeding requiring transfusion.

The final successful CTO revascularization strategy was antegrade dissection reentry in 18% of patients, retrograde dissection reentry in 30%, antegrade wire escalation in 34%, and retrograde wire escalation in 18%. A switch from the initial algorithm-based strategy to a second strategy occurred in 41% of patients, and a third strategy was employed in 9%.

 

“I think the key message is you need to have more than one option to treat complicated disease. Half of patients had a switch in strategy,” Dr. Walsh observed.

Intravascular ultrasound (IVUS) adjudication in the central core lab showed a humbling rate of discordance between the operators’ impression of how their procedures were proceeding and what was really going on.

“There’s a bit of a mantra [that says] if you’re wiring stuff you’re always in the lumen, and if you’re using dissection techniques you’re always not in the lumen. In fact, that’s nonsense. You get it wrong one in six times. When you use IVUS adjudication to see if you’re outside the lumen or not, with wire-based retrograde escalation you’re out of the lumen and in the subintimal space 27% of the time. And with dissection strategies you’re wrong in about 15%,” according to the cardiologist.

He described the study participants as “extremely limited” at baseline as evidenced by their scores on the Seattle Angina Questionnaire Physical Limitation, Angina Stability, and Angina Frequency domains. At 12 months of follow-up, patients averaged 20- to 40-point improvements across all three domains.

One member of the discussion panel expressed a wish that the study had included a sham PCI arm. He raised the possibility that PCI had exerted an enormous placebo effect that could conceivably account for the substantial quality of life benefits documented in the study. But another panelist scoffed at this notion. This wasn’t a modest improvement in quality of life, nor was it measured after a mere 6 weeks, as was the case in the sham-controlled ORBITA trial.

“It’s really difficult to imagine a sham effect that persists out to a year,” he argued.

Dr. Walsh reported receiving research grants from and serving as a consultant to Boston Scientific, which funded the CONSISTENT CTO Study.

bjancin@mdedge.com

 

PARIS – The so-called hybrid strategy is now the preferred approach to percutaneous coronary intervention (PCI) for chronic total occlusions (CTO), 12-month outcomes of the multicenter observational CONSISTENT CTO trial suggest, according to Simon J. Walsh, MD, an interventional cardiologist at Belfast Health and Social Care Trust.

Bruce Jancin/MDedge News

With use of the hybrid strategy, a CTO’s anatomic complexity is no longer a barrier to performing PCI with a success rate that by former standards would be considered astronomical, he said in presenting the CONSISTENT CTO results at the annual meeting of the European Association of Percutaneous Cardiovascular Interventions.

Indeed, the key take-home messages from CONSISTENT CTO were that technical success rates were dramatic at 98.6%, the target vessel failure rate at 12 months was impressively low at 5.24%, and quality of life scores showed clinically meaningful gains maintained through 1 year.

“Opening a CTO makes people better, reduces their symptom burden, and is something worth doing,” Dr. Walsh concluded.

That hasn’t always been the prevailing view. Historically, most interventional cardiologists had a pessimistic attitude regarding PCI for CTOs. The procedures had a low technical success rate, frequent complications, and lousy durability. Moreover, these subpar results came at a considerable price in terms of extensive radiation exposure and catheterization laboratory time. These various shortcomings became particularly prominent when traditional wire-based PCI strategies were applied to long, complex occlusions.

All that has changed as a result of improved stent technologies and procedural techniques, along with the development of the hybrid PCI algorithm by U.S. cardiologists. Using these tools, an interventionalist skilled in the hybrid strategy now selects cases on the basis of clinical indications, such as disabling angina, rather than on anatomic considerations. This point was emphatically brought home in CONSISTENT CTO (Conventional antegrade vs. sub-intimal synergy stenting in chronic total occlusions).

“This is the most complex set of treated CTO lesions ever investigated in this rigorous way,” according to Dr. Walsh.

This assertion was bolstered by the fact that the average Japan CTO (JCTO) score in the 210 study participants was 2.4, climbing to 2.9 in the 101 patients with dissection present. Further adding to the lesion complexity was the fact that roughly one in five subjects had a degenerated coronary artery graft in their target vessel. The average lesion length as measured at the study core lab was 29.1 mm. The impetus for the CONSISTENT CTO Study was a recognition that, even though a growing number of skilled operators are embracing the hybrid PCI strategy with heretofore unprecedented favorable results, there remains an evidence gap, with little in the way of long-term studies featuring rigorous follow-up. Participants in CONSISTENT CTO therefore underwent baseline formal quality of life assessment, repeated at 12 months of follow-up together with angiography and/or optical coherence tomography. Further follow-up is planned at 2, 3, and 5 years.

Of the 231 patients who consented to participate in the study, 210, or 90%, were able to have their CTO opened with a Synergy everolimus-eluting stent. Those 210 constituted the study population.

 

The hybrid algorithm-based PCI strategy utilizes an individual’s CTO anatomy to dictate the initial choice of approach. The goal is to pick the strategy that is most likely to achieve successful outcome efficiently, with minimal contrast and radiation doses for that particular type of CTO. The hybrid algorithm begins with dual-catheter injection and intravascular ultrasound aimed at determining whether four key anatomic features are present: an ambiguous proximal cap, a poor distal target, good interventional collaterals, and a major side branch at the distal cap.

If those four features are absent and the CTO lesion is less than 20-mm long, the algorithm dictates that the initial approach is antegrade wire escalation; if the lesion is 20 mm or more, the first approach is antegrade dissection reentry. However, if those anatomic features are present, the initial strategy is retrograde wire escalation if the lesion is less than 20 mm, and retrograde dissection reentry for longer lesions. When the initial approach fails, structured protocols dictate the selection of second and third approaches (JACC Cardiovasc Interv. 2012 Apr;5[4]:367-79).

The right coronary artery was the site of the CTO in 70% of study participants. Dual-catheter access was utilized in 79% of patients; only 10% had exclusively radial access. An average of 2.8 Synergy stents were deployed, with a whopping mean total stent length of 96.6 mm in the 48% of patients with dissection and 75.4 mm in those without. Mean procedure time was 122 minutes, with a fluoroscopy time of 44.6 minutes.

The primary efficacy endpoint was the rate of target vessel failure (TVF) at 12 months, defined as cardiac death, MI related to the target vessel, or any ischemia-driven revascularization of the target vessel. The rate was 5.24%.

“We were pleasantly surprised by that,” Dr. Walsh admitted.

Indeed, based upon studies of PCI for CTO published by other investigators, he and his colleagues had initially projected a 13% TVF rate, then bumped it up to 15% because of the high degree of lesion complexity.

Diabetes was the main predictor of target vessel revascularization.

At the time of the index PCI, 19% of patients were scheduled to return for an early optimization procedure within 3 months. This was arranged when operators anticipated significant positive remodeling would occur as the target vessel readjusted to blood flow or distal disease of borderline severity was noted beyond the CTO segment. These were not counted as adverse events. Half of the returnees underwent angiography and no further action was undertaken. The others underwent postdilation of their Synergy stents or new stenting of distal disease.

Complete revascularization of the target territory was achieved in 98.6% of patients. Key complications consisted of 5 perforations, 10 hematomas at vascular access sites, 2 cases of pericardiocentesis, and 4 instances of bleeding requiring transfusion.

The final successful CTO revascularization strategy was antegrade dissection reentry in 18% of patients, retrograde dissection reentry in 30%, antegrade wire escalation in 34%, and retrograde wire escalation in 18%. A switch from the initial algorithm-based strategy to a second strategy occurred in 41% of patients, and a third strategy was employed in 9%.

 

“I think the key message is you need to have more than one option to treat complicated disease. Half of patients had a switch in strategy,” Dr. Walsh observed.

Intravascular ultrasound (IVUS) adjudication in the central core lab showed a humbling rate of discordance between the operators’ impression of how their procedures were proceeding and what was really going on.

“There’s a bit of a mantra [that says] if you’re wiring stuff you’re always in the lumen, and if you’re using dissection techniques you’re always not in the lumen. In fact, that’s nonsense. You get it wrong one in six times. When you use IVUS adjudication to see if you’re outside the lumen or not, with wire-based retrograde escalation you’re out of the lumen and in the subintimal space 27% of the time. And with dissection strategies you’re wrong in about 15%,” according to the cardiologist.

He described the study participants as “extremely limited” at baseline as evidenced by their scores on the Seattle Angina Questionnaire Physical Limitation, Angina Stability, and Angina Frequency domains. At 12 months of follow-up, patients averaged 20- to 40-point improvements across all three domains.

One member of the discussion panel expressed a wish that the study had included a sham PCI arm. He raised the possibility that PCI had exerted an enormous placebo effect that could conceivably account for the substantial quality of life benefits documented in the study. But another panelist scoffed at this notion. This wasn’t a modest improvement in quality of life, nor was it measured after a mere 6 weeks, as was the case in the sham-controlled ORBITA trial.

“It’s really difficult to imagine a sham effect that persists out to a year,” he argued.

Dr. Walsh reported receiving research grants from and serving as a consultant to Boston Scientific, which funded the CONSISTENT CTO Study.

bjancin@mdedge.com