Impact of glycemic variability on myocardial infarct size in patients with ST-segment elevation myocardial infarction: quantitative assessment of left ventricular wall motion severity.

Glycemic variability (GV) is relevant to impaired myocardial salvage in acute ST-elevation myocardial infarction (STEMI). Severity of hypokinesis at the infarct site as assessed from contrast left ventriculography can reportedly predict infarct size in STEMI. We prospectively studied 58 consecutive patients (mean age, 63 ± 11 years) with anterior or inferior STEMI who underwent successful reperfusion therapy. Mean amplitude of glucose excursion (MAGE) was obtained from continuous glucose monitoring system. Patients were divided into the upper tertile of MAGE as Group H, and the other two-thirds as Group L. Serial regional wall motion severity at the infarct site was computed postprocedure and at follow-up using a quantitative left ventricular analysis system. Impaired myocardial salvage was defined as severity recovery ratio < 20%. Significantly shorter onset-to-balloon time (196.9 vs. 279.0 min, p = 0.033) and relatively lower postprocedural wall motion severity (2.4 vs. 2.9, p = 0.096) were observed in Group H, but absolute severity recovery was significantly smaller in Group H (0.5 vs. 1.3, p = 0.017). Multivariate analysis showed higher MAGE as predictive of impaired myocardial salvage (OR, 406.10; 95% CI, 4.41-37,366.60; p = 0.009). Recovery of reginal wall motion severity at the infarct site was compromised in STEMI patients with higher MAGE. Our results suggest that final infarct size is potentially larger than expected in STEMI patients with higher GV.

Impact of Institutional and Operator Volume on Short-Term Outcomes of Percutaneous Coronary Intervention: A Report From the Japanese Nationwide Registry.

OBJECTIVES: The aim of this study was to assess the volume-outcome relationship for PCI within the nationwide registration system in Japan. BACKGROUND: The effect of site and operator case load for percutaneous coronary intervention (PCI) on outcomes has not been investigated thoroughly in non-Western regions. METHODS: In the present study, PCI procedural data recorded between January 2014 and December 2015 in the Japanese PCI registry, a nationwide registration system, were analyzed. Institutions and operators were categorized into deciles based on the number of PCIs performed per year. Odds ratios (ORs) for in-hospital mortality and the composite endpoint (in-hospital death and periprocedural complications) were estimated for each decile (with the lowest volume group as a reference group). RESULTS: A total of 323,322 PCIs (at 625 hospitals [median PCI cases/year: 216; quartiles: 121 to 332] by 4,211 operators [median PCI cases/year: 28; quartiles: 10 to 56]) were analyzed, of which 2,959 patients (0.9%) and 7,205 patients (2.2%) experienced in-hospital mortality and the composite endpoint after PCI, respectively. The adjusted risk for in-hospital mortality and the composite endpoint was significantly higher in hospitals included in the lowest decile (<150 PCIs/year); the risk remained consistently low across the remaining deciles. Contrastingly, no significant volume-outcome relationship was observed between operator volume and outcomes. A similar trend was observed when the analysis was confined to emergency/urgent PCI cases. CONCLUSIONS: In contemporary Japanese PCI practice, lower institutional volume was related inversely to in-hospital outcomes, but the association of annual operator volume with outcomes was less clear.