Rapid Inflammasome Activation Is Attenuated in Post-Myocardial Infarction Monocytes

Inflammasomes are crucial gatekeepers of the immune response, but their maladaptive activation associates with inflammatory pathologies. Besides canonical activation, monocytes can trigger non-transcriptional or rapid inflammasome activation that has not been well defined in the context of acute myocardial infarction (AMI). Rapid transcription-independent inflammasome activation induced by simultaneous TLR priming and triggering stimulus was measured by caspase-1 (CASP1) activity and interleukin release. Both classical and intermediate monocytes from healthy donors exhibited robust CASP1 activation, but only classical monocytes produced high mature interleukin-18 (IL18) release. We also recruited a limited number of coronary artery disease (CAD, n=31) and AMI (n=29) patients to evaluate their inflammasome function and expression profiles. Surprisingly, monocyte subpopulations isolated from blood collected during percutaneous coronary intervention (PCI) from AMI patients presented diminished CASP1 activity and abrogated IL18 release despite increased NLRP3 gene expression. This unexpected attenuated rapid inflammasome activation was accompanied by a significant increase of TNFAIP3 and IRAKM expression. Moreover, TNFAIP3 protein levels of circulating monocytes showed positive correlation with high sensitive troponin T (hsTnT), implying an association between TNFAIP3 upregulation and the severity of tissue injury. We suggest this monocyte attenuation to be a protective phenotype aftermath following a very early inflammatory wave in the ischemic area. Damage-associated molecular patterns (DAMPs) or other signals trigger a transitory negative feedback loop within newly recruited circulating monocytes as a mechanism to reduce post-injury tissue damage.

Performance of One- Compared With Two-Catheter Concepts in Transradial Coronary Angiography (from the Randomized Use of Different Diagnostic Catheters-Radial-Trial)

The Use of Different Diagnostic Catheters-Radial-Trial sought to compare the safety and efficacy of one-catheter concepts (OCC) using Tiger II or BLK catheters with two-catheter concepts (TCC) using standard Judkins catheters for transradial coronary angiography. A total of 300 patients planed for coronary angiography were enrolled into this single-center, single-blinded trial. Patients were randomized in a 2:1 ratio to either OCC by Tiger II (n = 100) and BLK (n = 100) or TCC by Judkins (n = 100) catheters. Primary end point was time required to perform a complete coronary angiography. Coronary angiography duration was 603 ± 29 seconds and 552 ± 26 sec in the OCC and the TCC groups (p = 0.052). Fluoroscopy time was longer in the OCC (408 ± 28 sec) as compared with the TCC group (258 ± 28 sec, p = 0.009) and the amount of contrast volume used significantly higher (98 ± 5 ml vs 67 ± 4 ml, p < 0.001). Crossover rates were increased in the OCC as compared with the TCC group (37% vs 4%, p < 0.001). These effects were observed irrespective of OCC catheter type. In conclusion, this study demonstrates that OCC do not reduce angiography time, but are associated with an increased amount of contrast volume and longer fluoroscopy time as compared with TCC.