Epinephrine-induced electrical storm after aortic surgery.

Electrical storm (ES) is a potentially lethal syndrome defined as three or more sustained episodes of ventricular tachycardia or ventricular fibrillation within 24 h. There are multiple inciting factors for ES, one of which involves excess catecholamine (endogenous and exogenous) effects. Exogenous catecholamines used for hemodynamic support can paradoxically engender or exacerbate an underling arrhythmia leading to ES. We report on an 63-year-old man who presented for repair of an ascending aortic dissection. After cardiopulmonary bypass separation assisted with high-dose epinephrine, ES developed requiring over 40 defibrillatory shocks. The epinephrine infusion was held and within 5 min, the ES self-terminated. ES in the context of cardiovascular surgery with the use of epinephrine for hemodynamic support has not be previously reported. Clinicians need to be cognizant of the seemingly paradoxical effect of epinephrine to induce ES. Initial ES treatment involves acute stabilization (treating or removing exacerbating factors (i.e., excess catecholamines)).

The effect of CT-based attenuation correction on the automatic perfusion score of myocardial perfusion imaging using a dedicated cardiac solid-state CZT SPECT/CT.

BACKGROUND: Data regarding cardiac cadmium-zinc-telluride (CZT)-specific augmented databases and their impact on CT-based attenuation correction (AC) perfusion scores in myocardial perfusion imaging (MPI) were obtained on a multiple-pinhole CZT SPECT/CT. METHODS AND RESULTS: Summed stress (SSS) and rest scores (SRS) were measured using automated software in three independent patient groups: group 1 (n = 80) underwent MPI on both CZT and conventional sodium iodide (NaI) devices, group 2 (n = 80) with low coronary artery disease likelihood and normal MPI provided reference CZT databases; and group 3 (n = 152) served to compare AC and non-AC (NAC) scores on CZT. Group 1 CZT and NaI scores gave a significant 1:1 linear correlation for CZT scores referenced to the custom database vs NaI scores referenced to the default database, but these were not concordant when CZT scores were referenced to the default database. AC significantly decreased average SSS and SRS in men vs NAC, 4.29 ± 6.30 vs 5.37 ± 7.26 (P < 0.001) and 2.37 ± 4.72 vs 3.13 ± 5.85 (P < 0.001), but not in women, 2.28 ± 3.42 vs 2.28 ± 3.08 (p NS) and 0.46 ± 1.51 vs 0.61 ± 1.86, (p NS), respectively. CONCLUSIONS: Specifically designed databases for solid-state CZT cardiac SPECT provide accurate quantitation of perfusion scores concordant with those previously validated for conventional SPECT. AC and NAC CZT scores differed significantly, especially in men.