JACC in a Flash
Similar Efficacy, Safety Between Biodegradable Polymer DES
and Second-Generation Durable Polymer DES
Biodegradable polymer drug-eluting stents (DES) were found to be similar in safety and efficacy when compared with second-generation durable polymer DES, according to a study published March 6 in JACC: Cardiovascular Interventions.
Georges El-Hayek, MD, and colleagues analyzed 16 randomized controlled trials. The meta-analysis included 19,886 patients, with 10,859 receiving a biodegradable polymer DES and 9,027 receiving durable polymer DES.
At follow-up, biodegradable polymer DES were not associated with any reduction in the risk of target vessel revascularization compared with second-generation durable polymer DES. From a safety standpoint, no difference was observed between the two groups in the risk of cardiac death or myocardial infarction. The two groups also had similar rates of stent thrombosis after one year. There were no significant differences between the two groups in regard to target vessel revascularization, cardiac death, myocardial infarction and stent thrombosis in patients who received biolimus-eluting versus sirolimus-eluting biodegradable polymer DES. No differences were seen based on the biodegradable polymer DES scaffolding material or when comparing durable polymer DES with thin struts and thick struts.
In an accompanying editorial comment, Jeffrey W. Moses, MD, FACC, and Vivian G. Ng, MD, write that this information should be interpreted with caution due to the differences in types of biodegradable polymer DES. However, they add that this study “is an impressive large meta-analysis that provides the power needed to determine the efficacy of biodegradable polymer DES and supports the safety and efficacy of second-generation durable polymer DES when compared to biodegradable polymer DES. Although this meta-analysis did not demonstrate superiority of this new technology over second-generation durable polymer DES, biodegradable polymer DES should not be marginalized and disregarded.”
El-Hayek G, Bangalore S, Casso Dominguez A, et al. JACC Cardiovasc Interv 2017;10:462-71.
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JACC in a Flash
Long-Term Outcome of Stenting the Proximal
Versus Non-proximal LAD
For patients undergoing drug-eluting stent (DES) implantation, long-term outcomes were similar regardless of whether or not the target lesion was in the proximal left anterior descending (LAD) artery, according to a study published March 20 in JACC: Cardiovascular Interventions.
Researchers led by Ariel Roguin, MD, PHD, compared the outcomes of 2,534 patients with stents implanted in the proximal LAD to 6,172 patients with stents implanted outside the proximal LAD. All patients were enrolled in the PROTECT trial, a multicenter trial of PCI. Compared with the non-proximal LAD cohort, patients in the proximal LAD cohort were slightly younger, had fewer atherosclerotic risk factors, fewer previous coronary revascularization procedures and more had unstable angina.
Major adverse cardiac events (MACE) were higher in the proximal LAD cohort at one, two and three years, but not at four years. At 30 days, cardiac mortality was higher in the proximal LAD cohort, but this was not observed at later follow-up. At four years of follow-up, target lesion failure was 12.3 percent in the proximal LAD cohort versus 10.4 percent in the non-proximal LAD cohort and target vessel failure was 14.8 percent versus 13.5 percent. A greater number of myocardial infarctions (MI) were observed in the proximal LAD group (6.2 percent versus 4.9 percent). Drug-eluting stent type had no interaction on MACE or target vessel failure.
The researchers conclude that these findings “may suggest that proximal LAD lesion may not confer a substantial additional risk in the DES era.”
In an editorial comment published with the paper, Elizabeth M. Holper, MD, MPH, FACC, writes that there are a number of concerns about the study that must be acknowledged, including confounders that have not been accounted for, because it was a post hoc analysis that was not pre-specified. Additionally, when the results are placed in the context of patient care, the different patient profiles of the two cohorts must be noted. Finally, the adverse outcomes require further evaluation.
“The risk of higher MI and higher repeat vascularization with PCI is part of the equation to consider,” she writes. “Given that the randomized trial of PCI versus coronary artery bypass grafting for proximal LAD lesions is unlikely to occur, is this trial enough to move the needle a little more away from surgery or is the proximal LAD still one of the last lesions standing? The answer may be that it depends on which outcomes are considered most important to the patient and the physician.”
Roguin A, Camenzind E, Kerner A, et al. JACC Cardiovasc Interv 2017;10:548-56.
JACC in a Flash
Lower Mortality Seen in Direct Admission
Versus Inter-hospital Transfer PCI
Patients with STEMI treated with PCI experienced lower 12-month mortality when directly admitted to a primary PCI center compared with patients who were transferred via a regional non–PCI-capable facility, according to a recent study in JACC: Cardiovascular Interventions.
Damian Kawecki, PhD, and colleagues analyzed the data of 70,093 STEMI patients from the Polish registry of Acute Coronary Syndromes (PL-ASC) between 2006 and 2013. A total of 39,144 (58 percent) patients were admitted directly to a primary PCI center while 30,947 (44.2 percent) were transferred to a primary PCI center via a regional non–PCI-capable facility. The proportion of direct admission increased significantly throughout the study period, reaching 68 percent in 2013.
Transferred patients were admitted to primary PCI centers with significantly longer delays – the absolute difference in the time from median symptom onset to admission was 44 minutes. However, their admission-to-PCI time was four minutes shorter. This resulted in a median time from symptom onset to PCI of 228 minutes in the direct admission group and 270 minutes in the transfer group.
Among patients admitted directly, 13.6 percent had PCI performed in less than two hours from symptom onset, compared with 9.0 percent of transferred patients. In a propensity-matched multivariate Cox analysis, direct admission and shorter symptom-to-admission time were significant predictors of lower 12-month mortality.
In the PL-ASC registry, time delays to primary PCI were still lengthy despite an increase in the density of catheterization laboratories in the STEMI network, which doubled between 2006 and 2013. According to the authors, even with the continued optimization of invasive treatment and the high incidence of acute MI, transport to a primary PCI center remains as a major phase and concern in relation to STEMI care, because the majority of patients in both groups in their analysis were treated outside the time spans required for the greatest impact of reperfusion on myocardial salvage. However, the adjusted data indicate that even over these time spans, a shorter time to reperfusion results in better outcomes.
In an accompanying editorial comment, Peter B. Berger, MD, FACC, and colleagues write that researchers “deserve credit for shining a light on suboptimal STEMI practices in their native Poland. Clinician-investigators in the United States have been doing the same, and it is clear that many areas of the United States are in need of process improvements if clinicians want to optimize STEMI-related health outcomes. We know what has to be done. Now is the time to act.”
Kawecki D, Gierlotka M, Morawiec B, et al. JACC Cardiovasc Interv 2017;10:438-47.
JACC in a Flash
Strategies for Left Main Bifurcation
PCI for left main coronary stenosis using second-generation drug-eluting stents (DES) is safe and the outcomes are comparable with those with CABG, according to a review of current studies by Tanveer Rab, MD, and colleagues, presented March 17 at ACC.17 and simultaneously published in JACC: Cardiovascular Interventions. Target lesion revascularization (TLR), however, remains an issue, they found.
In patients whose SYNTAX score is low or intermediate, PCI has been established as a safe alternative to CABG, and this has been supported by the recent results from the EXCEL and NOBLE studies, state the authors. They conducted this review to provide guidance on patient selection, risk scoring, intracoronary imaging, vessel preparation and selection of the stenting technique. A single-stent provisional approach was found to be the preferred strategy.
Left main bifurcation is present in more than 80 percent of left main stenoses, and drivers of the choice of the stent technique are potential complications to left circumflex and TLR. Among the challenges for PCI of the left main bifurcation are the need for larger stents, an understanding of the stent platform to expand and identifying diffuse left main disease.
A heart team approach for elective PCI is recommended by the authors, and facilities that have intravascular ultrasound or optical coherence and the capacity to assess coronary physiology, as well as access to atherectomy and mechanical circulatory support. Pre-procedure assessment and planning is critical to success, and includes using the Medina angiographic classification of the complexity of the bifurcation lesion and imaging and functional assessment.
An algorithm for the management of left main bifurcation is provided by the authors, along with a scheme of treatment options for left main disease that incorporates the guideline recommendations. The authors also provide insights on hemodynamic support for high-risk PCI, lesion classification, and stenting technique for simple and complex lesions.
Rab T, Sheiban I, Louvard Y, et al. JACC Cardiovasc Interv 2017;March 17:[Epub ahead of print].
JACC in a Flash
Greater Radiation Exposure With Radial Versus Femoral PCI
Operators and patients are exposed to more radiation with the radial approach compared with the femoral approach to PCI for acute coronary syndrome, according to the results of a study presented at ACC.17 and simultaneously published in JACC: Cardiovascular Interventions. The study – the largest so far on this topic – was conducted in Italy, the Netherlands, Spain and Sweden between October 2011 and November 2014.
In RAD-MATRIX, a sub-study of the MATRIX study, 18 operators wore dosimeters and data were collected on fluoroscopy time and dose area product (DAP) from a total of 777 procedures performed in 767 patients. Dosimeters were worn on the left wrist, at mid-thorax, and at the head level to measure eye exposure. Patient exposure was measured indirectly using a conversion factor of 0.20 mSv per Gy cm2.
The primary endpoint of the radiation dose at the thorax of the operator was significantly higher with radial access (77 µSv vs. 41 µSv with femoral access; p = 0.02) – and did not differ by right or left radial access. The study did not achieve non-inferiority for the primary hypothesis of the radial access not being associated with a higher operator dose than the femoral access (p value for non-inferiority 0.843).
The difference in the primary endpoint remained significant after normalization of the operator dose by fluoroscopy time or DAP. There was no difference in the radiation dose at the wrist or head of the operator between the two strategies.
For patients, the median fluoroscopy time was longer with radial than with femoral access (10.2 min vs. 9.1 min; p < 0.0001). Likewise, the median DAP was higher with the radial access (64.7 Gy cm2 vs. 59.1 Gy cm2; p = 0.0001).
Alessandro Sciahbasi, MD, PhD, et al., write that the average increase in radiation exposure was relatively small, at about 10 percent, for patients undergoing radial rather than femoral access PCI. However, for operators, there was a two-fold increase in radiation exposure at the thorax with the radial approach. Further, they state their results confirm DAP is a weak predictor of radiation exposure for operators.
Of note, the incremental increase in the operator’s radiation exposure for a single procedure by radial access versus femoral access is in the range of 1.1 µSv, corresponding to an additive 300 µSv for every 300 procedures – similar to the additive radiation exposure of 17 chest X-rays.
Schiahbasi A, Frigoli E, Sarandrea A, et al. JACC Cardiovasc Interv 2017;March 18:[Epub ahead of print].