P5522ST elevation myocardial infarction networks: relationship of hub-spoke distance with transfer time and clinical outcomes in rescue PCI

Background

In the establishment of ST elevation myocardial infarction (STEMI) systems of care, transfer times between primary care units (PCU) and the cardiac catheterization lab (CCL) are pillars to therapeutic success. Objective: To analyze the relationship between PCU-CCL distance with transport time and main clinical outcomes in STEMI patients (p) treated with pharmaco-invasive therapy (PIT) and referred for rescue PCI after failed fibrinolysis.

Methods

Between January 2010 and December 2018, of the 2241 patients who received tenecteplase in PCU inserted in a large city STEMI network, 801 (35.7%) evolved without reperfusion criteria after 90 minutes (persistence of chest pain, less than 50% reduction on ST elevation or hemodynamic instability), being urgently transferred to the CCL. The PCU were divided according to the distance to the tertiary center in Group 1: between 5 and 9km (N=208p), Group 2: between 16 and 18km (N=315p) and Group 3: between 22 and 30km=266p). Considering an alpha of 0.05, sample size n=801 and an effect size of 0.11, a power of 0.80 was obtained.

Results

The groups were comparable for baseline features (Table 1). Group 2 (intermediate distances) had the highest median transport time (G1 260 interquartile 145–437 min vs G2 355 interquartile 206–573 min vs G3 241 interquartile 125–418 min; p<0.01 for G2). There were no differences between the groups regarding cardiogenic shock (G1 24.5% vs G2 23.3% vs G3 24.1%, p=0.9) or in-hospital death (G1 17.4% vs G2 12.3% vs G3 13.0%, p=0.2).

Table 1. Group's baseline features G1: Short distances G2: Intermediate distances G3: Long distances p value (5–9 km) N=208 (16–18 km) N=315 (22–30 km) N=266 Age (median) 57.5 (51–64) 57 (49–66) 59 (52–67) 0.27 Female 29.7% 28.3% 35.1% 0.19 Hypertension 67.3% 60.9% 64.4% 0.31 Diabetes 37.0% 32.1% 37.8% 0.30 Renal failure 10.3% 9.7% 6.3% 0.21 Anterior STEMI 56.1% 58.4% 62.4% 0.36 Pain-to-needle time (median min) 197.5 (137–330) 195 (120–295) 195 (125–345) 0.38

Conclusion

In STEMI patients with failed fibrinolysis treated with pharmaco-invasive therapy, the PCU-CCL distance was not related to transfer time or to outcomes of in-hospital death and cardiogenic shock. The longer transport time of hospitals located at intermediate distance can possibly reflect local logistical difficulties and are not due to hub-spoke distance. Continuous improvement in structuring and coordination of public STEMI networks is aimed.

P2269IABP-SHOCK II risk score validation for cardiogenic shock after myocardial infarction in a cohort treated with pharmaco-invasive therapy

Background

Risk stratification using scores is a valuable tool in cardiogenic shock after ST elevation myocardial infarction (STEMI). During pharmacoinvasive therapy (PIT) their use is unexplored in the literature. Objective: To validate the IABP-SHOCK II (Intra-aortic Balloon Pump in Cardiogenic Shock) score in patients treated with PIT and to analyze the influence of ischemia time on the different risk strata.

Methods and results

Of 2,143 STEMI patients seen between May 2010 and April 2017, 212 (9.9%) developed cardiogenic shock. Thirty-one patients (14.6%) with incomplete data were excluded from the analysis and the validation cohort included the remaining 181. Mortality rates were similar between the analyzed and excluded patients (42.5% and 45.1% respectively, p=0.77). The 30-day mortality using the IABP-SHOCK II score was 26.6% for low-risk (n=94), 53.2% for moderate-risk (n=62), and 76% for high-risk (n=25) (p<0.001). The validation of the score showed good discrimination for death, with an area under the curve of 0.73 (95% confidence interval 0.66 to 0.81 p<0.001). Although pain-to-needle time was significantly longer in patients who died within 30 days (251 min, interquartile range 140–528 vs. 210 min, interquartile range 130–343, p=0.032), the median intervals of pain-to-needle and fibrinolytic-catheterization showed no association with the group stratification (220 vs 251 vs 200 min; p=0.22 and 390 vs 435 vs 315 min; p=0.18, respectively). This finding may be explained by the potential of these variables to be more closely associated with the development of cardiogenic shock in STEMI patients treated with PIT, and to be less associated with progression to death when the patient is already in shock.

30-day mortality in scored strata

Conclusion

In patients with cardiogenic shock after STEMI treated with PIT, risk stratification using the IABP-SHOCK II score was adequate. There was no influence of pain-to-needle and fibrinolytic-catheterization times on the ability to the score model stratification.

Immobilization studies of an industrial penicillin acylase preparation on a silica carrier

Penicillin acylase (EC 3.5.1.11) was immobilized by covalent binding on a silica gel carrier activated by silanization. High immobilization yields, operational stability, enzyme loading and support reutilization capacity were obtained. The effects of several variables on the activation of the support and on the immobilization method were studied. Other supports and immobilization methods were assessed for the immobilization of penicillin acylase and compared with the basic process used. Activity versus temperature, pH, buffer molarity and penicillin concentration profiles were determined and compared for the free, crosslinked and covalently-bound silica carrier penicillin acylase preparations. The hydrolysis performance of the latter preparation was assessed in a batch basket reactor and the time course of the hydrolysis reaction modelled by a two parameter model equation. The operational stabilities of penicillin acylase coupled covalently to the silica gel support and immobilized by a crosslinking procedure using glutaraldehyde were also compared.

Cryosurgical treatment of a large keloid

The cryosurgical treatment of a patient with a large keloid on the nuchal region is reported. The tumor was frozen under local anesthesia with minimal discomfort. The temperatures beneath the lesion were monitored in order to achieve a deep freezing. Twelve months after the treatment the tumor has not recurred.