P5602In-hospital clinical outcomes of patients with ST elevation myocardial infarction undergoing pharmaco invasive therapy 6 to 12 hours after symptoms onset

Abstract

Background: Current Guidelines recommend treating ST Elevation Myocardial Infarction (STEMI) up to 12 hours after symptoms onset with Primary Percutaneous Coronary Intervention (PPCI). In developing countries this is a challenge, as only 6.5% of PPCI is done in the public health system of our country and mean STEMI mortality is still 15%. As the STREAM Trial showed equivalence of Pharmaco Invasive Therapy (PIT) compared to PPCI in the first 3 hours after onset of symptoms, renewed interest occurred in the utilization of PIT in regional systems of care, due to its favorable logistics. Little information exists on results of STEMI treatment with PIT in the period six to twelve hours after symptoms onset. Purpose: To assess results of STEMI treatment with PIT in patients presenting from 6 to 12 hours after symptoms onset. Methods: From Jan-2010 to Dec-2016 data was collected prospectively. Patients from 14 Emergency Departments (ED) received tenecteplase (TNK) and adjuvants if they couldn't reach a PPCI Hospital within 90 minutes. After initial therapy, patients were transferred to a single tertiary PCI Hospital to perform routine cath 3-24 hours after lysis, or as soon as possible if rescue was needed. This public STEMI network received all comers with no transfer request denied. TNK was always employed full dose. Exclusion criteria were only absolute contraindications for lysis or angiography. TIMI and BLUSH were interpreted by a single experienced interventional cardiologist. Results: Among 1981 patients, 334 patients (16.8%) presented from 6 to 12 hours of symptom onset, mean age was 58.1 years old (21-93 yo) and 66.1% were male. Demographics revealed hypertension in 64%, smokers in 62.5%, dyslipidemia in 58.6%, Diabetes in 38.6%, chronic kidney disease in 13.4% and previous MI in 11.9%. Baseline TIMI and BLUSH flow revealed TIMI 0 (21.4%), I (5.6%), II (10.8%), III (62.2%) and BLUSH 0 (37.7%), I (4.2%), II (3.4%) and III (54.7%). The following final TIMI and BLUSH were encountered in 285 cases: TIMI 0 (6.7%), I (14.0%), II (10.1%), III (69.2%) and BLUSH 0 (32.8%), I (7.2%), II (3.1%), III (56.9%). Killip III or IV occurred in 24.5%, total AV block in 14.4%, sustained unstable ventricular arrhythmias or cardiac arrest in 9.6%, mitral insufficiency in 6.7%. TIMI major bleeding developed in 4.5%, ischemic stroke in 8 cases (2.4%) and hemorrhagic stroke in 3 pts (0.9%). In-hospital mortality was 9.5% (32 patients). Conclusions: In STEMI patients undergoing PIT, late presentation (6 to 12 hours after symptoms onset) is associated with a high rate of major adverse events, including one quarter of patients having advanced heart failure. Although TIMI 0 flow decreased significantly after intervention, BLUSH 3 did not improve. All cause hospital mortality was 9.5%. A historical comparison with prior studies suggests that even in this very high-risk population, a pharmaco invasive strategy may play an important role in developing countries.