Clinical Editor's Corner

Seven Questions for the Cath Lab From 2008 and the Studies That Answer Them

morton kern, MD Clinical Editor Professor of Medicine Associate Chief Cardiology University of California Irvine Orange, California
morton kern, MD Clinical Editor Professor of Medicine Associate Chief Cardiology University of California Irvine Orange, California
Our work in the cath lab moves forward when supported by better patient outcomes, better safety and better cost savings. Much of what we used to do in the cath lab has changed based on comparisons between groups of patients treated in the ‘conventional’ way with that of a potentially better method, drug or device. This year, especially in the fall after the October 2008 TCT meeting, there were many new trials presented, some of which are likely to have importance for the cardiac cath lab. I thought it would be worthwhile to take a moment and review 7 studies presented over the past year that I think are worth remembering and may ultimately change the way we practice. Question: Do we have an oral antiplatelet agent better than Plavix? Is prasugrel better than clopidogrel for percutaneous coronary intervention (PCI) in acute coronary syndromes (ACS)? Category: Post PCI care Study Name: TRITON-TIMI 38 The Trial to Assess Improvement in Therapeutic Outcomes optimizing platelet inhibition with Prasugrel (TRITON-TIMI 38) was presented by Dr. Elliott Antman at the American Heart Association in Orlando, Florida in November 2007 and subsequently published (NEJM 2007;357:2001-2015). This study randomized 12,000 patients, 6,813 to prasugrel (loading dose and 10 mg maintenance) or clopidogrel, [(n=6795) 300 mg loading and 75 daily] with average follow up of 14.5 months. Cardiovascular death, myocardial infarction (MI) or stroke were lower in the prasugrel group compared with clopidogrel (10 vs. 12%, p 0.05) or MI between the two arms (p = 0.11). The incidence of cerebrovascular accident was significantly higher in the CABG arm (2.2% vs. 0.6%, p = 0.003), whereas the incidence of symptomatic graft occlusion and stent thrombosis was similar between the two arms (3.4% vs. 3.3%, p = 0.89). In LM patients, the overall 12-month MACCE event rate was lower with CABG (13.7% vs. 15.8%), although patients with LM only (8.5% vs. 7.1%) and LM + 1-VD (13.2% vs. 7.5%) seemed to do slightly better with PCI. Patients with LM + 2-VD (14.4% vs. 19.8%), LM + 3-VD (15.4% vs. 19.4%), or 3-VD alone (11.5% vs. 19.2%) seemed to do better with CABG than PCI. SYNTAX demonstrated that in patients with LM disease and/or severe 3-VD, CABG (with the use of at least one arterial graft) is superior to PCI with the Taxus DES, predominantly driven by the need for repeat revascularization in the PCI arm. CABG is, however, associated with a higher risk of cerebrovascular accidents (CVA) at 12 months, compared with PCI. As suggested in earlier PCI/CABG trials, the largest benefit from CABG seemed to be in patients with diabetes mellitus. Questions remain whether sirolimus-eluting stents (SES) may be associated with better outcomes in diabetic patients, compared with paclitaxel-eluting stents (PES), especially in the need for repeat revascularization. It is thus unknown if the use of SES instead of PES, or newer stents such as everolimus-eluting stents, would be associated with better outcomes in patients like these who undergo PCI. Question: If you have an STEMI at a non-PCI hospital, should you get heparin, half dose reteplase and abciximab then PCI or immediate transfer for rescue PCI? Category: STEMI management Study Name: CARESS This study was presented by Dr. Krzysztof Zmudka at the European Society of Cardiology Congress, August/September 2008, Munich, Germany and published this year [Di Mario C, Dudek D, Piscione F, et al. Immediate angioplasty versus standard therapy with rescue angioplasty after thrombolysis in the Combined Abciximab Reteplase Stent Study in Acute Myocardial Infarction (CARESS-in-AMI): an open, prospective, randomized, multicentre trial. Lancet 2008;371:559-68]. Study patients were admitted to hospitals without PCI capabilities and treated initially with heparin, half-dose reteplase, and abciximab, then randomized to immediate transfer for urgent PCI (n = 299) or standard therapy and rescue PCI if needed (n = 301). The primary endpoint of death, reinfarction or refractory ischemia at 30 days occurred less frequently in the immediate PCI group (4.4% vs. 10.7%, p = 0.005), driven by a reduction in refractory ischemia (0.3% vs. 4.0%, p = 0.003). Reinfarction rates, death rates, stroke rates and major bleeding were similar (all p = ns). At 1 year, MACE occurred in 11.4% of the immediate PCI group versus 16.4% of the standard therapy group (p = 0.07). Recurrent PCI occurred less frequently in the transfer group (14.4% vs. 42.4%, p 20 mm), especially those requiring overlapping stents. This study used OCT to examine sirolimus-eluting (SES), paclitaxel-eluting (PES), zotarolimus-eluting (ZES) and bare-metal stents (BMS) 6 months after implantation. The proportion of uncovered and/or malapposed struts when stents were overlapped tended to be higher with DES compared with BMS (5.4% vs. 1.8%, p = 0.08). The proportion of uncovered and/or malapposed struts was highest with SES (8.7%), followed by PES (8.3%) and then ZES (0.05%) (p 50%, excluding LM disease, previous bypass surgery and acute STEMI. The FFR ischemic threshold was ≤ 0.80 and those lesions were treated with DES, while vessels with FFR > 0.80 were treated medically. All patients were followed for one year. Four hundred ninety-six (496) patients were randomized to the angiographic and 509 patients to the FFR-guided strategies. There were no differences between groups with regard to clinical, angiographic or procedural characteristics. After one year, the FFR-guided approach used fewer stents per patient (2.7 ± 1.2 for the angio group and 1.9 ± 1.3 for the FFR group, p