• Myocardial Infarction
• Interventional Techniques & Devices Clinical Trials

Primary percutaneous coronary intervention (PCI) was not found to provide an advantage over fibrinolytic therapy for very elderly patients with acute myocardial infarction (AMI), according to findings from the Tratamiento del Infarto Agudo de Miocardio en Ancianos (TRIANA) trial (NCT00257309), which was halted early due to slow enrollment. Although TRIANA failed to meet its primary endpoint, it did show favorable (albeit nonsignificant) trends with an invasive strategy in this relatively unstudied group with a relatively small sample size.

PCI is the preferred therapy for ST-segment elevation MI (STEMI); yet the majority of very elderly patients (aged ≥75 years) with STEMI is treated with fibrinolytic therapy or no reperfusion therapy. Many physicians may be reluctant to use any reperfusion strategy in the elderly, given the sparse evidence that supports primary PCI and the fear of increased bleeding risk with fibrinolytic therapy in very elderly patients, said Professor Héctor Bueno, MD, PhD, Hospital General Universitario Gregorio Marañón, Madrid, Spain. Dr. Bueno presented results of the TRIANA trial, which was designed to compare the efficacy and safety of primary PCI and fibrinolytic therapy in patients aged ≥75 years.

TRIANA included patients aged ≥75 years (mean age, 81 years) who presented within 6 hours of symptom onset with STEMI and without contraindications for fibrinolysis at centers that offered primary angioplasty in Spain. Patients were randomly assigned to fibrinolytic therapy that consisted of weight-adjusted tenecteplase, unfractionated heparin, and clopidogrel (n=134) or primary angioplasty with clopidogrel and, at the physician's discretion, abciximab (n=132). The primary endpoint was the cumulative incidence of all-cause death, reinfarction, or disabling stroke at 30 days. Initially, the study was powered to detect a 40% relative risk reduction in the primary endpoint, based on a sample size of 560 patients. However, TRIANA was discontinued early due to slow recruitment after enrolling only 266 patients.

At 30 days, there were numerically fewer (but statistically not significant) primary endpoint events in the primary PCI group (18.9%) than in the fibrinolytic therapy group (25.4%; OR, 1.46; p=0.21). Each component of the primary endpoint tended to occur less frequently with PCI, including death (13.6% vs 17.2%; p=0.43), reinfarction (5.3% vs 8.2%; p=0.35), and disabling stroke (0.8% vs 3.0%; p=0.18). At 12 months, results for the primary endpoint again showed no statistically significant difference between treatment groups (27.3% vs 32.1%; p=0.31)

Among secondary outcomes, primary PCI significantly reduced the risk of recurrent ischemia compared with fibrinolysis (0.8% vs 9.7%; p<0.001). No differences were found between the primary PCI and fibrinolytic therapy groups in a range of safety outcomes, including major bleeding (3.8% vs 4.5%; p=0.78), need for transfusion (5.3% vs 3.0%; p=0.35), and renal failure (6.1% vs 7.5%; p=0.64).

Although TRIANA lacked the statistical power to demonstrate the superiority of PCI over fibrinolytic therapy, the observed risk reduction was consistent with the benefit that had been anticipated with primary PCI in the initial design of the study. Primary angioplasty should be considered the treatment of choice even in very old patients with STEMI. In situations in which primary PCI is not available, safety findings from TRIANA indicate that fibrinolysis may be considered as an alternative, with an acceptable rate of intracerebral hemorrhage among old patients who are carefully selected for fibrinolytic therapy.

• © 2009 MD Conference Express