The 2014 Transcatheter Cardiovascular Therapeutics conference held Sept. 13-15 in Washington, D.C., focused on the cutting edge in its late-breaking clinical trials and presentations. Here is a sampling.
Clinical Trials: IVUS-guided PCI beats out angiography for CTOs
For improved outcomes in patients with chronic total occlusion (CTO), intravascular ultrasound (IVUS)-guided PCI appears to win out over conventional angiography in a randomized trial that compared the two approaches when placing zotarolimus-eluting stents or biolimus-eluting stents into CTO patients.
During the 12-month follow-up, patients were found to have fewer combined incidents of MI, target vessel revascularization (TVR) and cardiac death. Irrespective of stent placed, IVUS-CTO patients experienced about one third as many combined MI, target vessel revascularization (TVR) and cardiac deaths as those who had stents placed via angiography (2.6 percent vs. 7.1 percent). At 12 months, angiography-guided CTO stenting had a TVR rate of 5.2 percent while IVUS-guided stents had 2.6 percent.
TAVR extends survival by two years
Transcatheter aortic valve replacement (TAVR) added more than two years to the life of inoperable patients with severe aortic stenosis, according to five-year results of the PARTNER I trial.
PARTNER was a controlled trial that randomized 358 patients with severe symptomatic stenosis to undergo transfemoral TAVR or standard care. At five years, the all-cause mortality rate for patients in the standard care group was 93.6 percent vs. 71.8 percent for the TAVR group, for an absolute difference of 22 percent. Median survival reached 29.7 months with TAVR vs. 11.1 months with standard care.
The five-year rehospitalization rate was lower in the TAVR group, at 47.6 percent vs. 87.3 percent. Stroke incidence remained higher in the TAVR group than in the standard care group but it mostly plateaued at six months and held steady after that period.
Simpler is better in side branch stenting
Fractional flow reserve (FFR)-guided side branch lesion stenting holds promise of fewer stents placed and more years between retreatment of stenosis in DKCRUSH-VI, a study that compared FFR-guided stenting against an angiography.
The FFR method, while more technically difficult, resulted in fewer stents being placed and a lower long-term restenosis rate. Similar rates of major adverse cardiac events were seen between the two groups.
Side branch treatment occurred in 56.3 percent of FFR cases vs. 63.2 percent of angiography-guided cases. Fewer stents were attempted in the FFR group, but were largely as successful as those in the angiography-guided group.
Six-week therapy fails to beat six months
Six weeks of triple therapy to provide anticoagulation to patients treated with drug-eluting stents was not superior to six months, according to results of the ISAR-TRIPLE trial.
ISAR-TRIPLE investigators set out to define the optimal duration of triple therapy by randomizing patients to six weeks or six months of clopidogrel (Plavix, Bristol Myers-Squibb/Sanofi Aventis) plus concomitant aspirin and oral anticoagulation with vitamin K antagonists after implantation with a drug-eluting stent.
They enrolled 307 patients in each arm. More than a quarter of patients in the six-week group continued clopidogrel after six weeks, though. At nine months, the rate of the composite of death, MI, definite stent thrombosis, stroke or TIMI major bleeding was 9.8 percent in the six-week group and 8.8 percent in the six-month group.
Several panelists questioned if the study was sufficiently powered to draw conclusions and said the crossover may have diluted results.
Scaffolds appear safe at one year
Fewer patients with coronary artery disease who were treated with a bioresorbable scaffold experienced new or worsening angina at one year than similar patients implanted with metal stents in the ABSORB II trial.
ABSORB II is evaluating the efficacy of an everolimus-eluting bioresorbable scaffold (Absorb, Abbott Vascular) compared with an everolimus-eluting metallic stent (Xience, Abbott Vascular). The study included 501 MI patients with one or two de novo lesions.
At one year, the acute lumen gain was 1.15 mm in the scaffold group vs. 1.46 mm in the stent group based on quantitative coronary angiography and 2.9 mm2 vs. 3.6 mm2 based on quantitative IVUS. The rate of new or worsening angina was 22 percent in the scaffold group vs. 30 percent in the stent group. Angina stages assessed with