Ishii Yosuke, Schuessler Richard B, Gaynor Sydney L, Yamada Kiyomi, Fu Annabel S, Boineau John P, Damiano Ralph J
Division of Cardiothoracic Surgery, Washington University School of Medicine, St Louis, Mo, USA.
Circulation. 2005 Jun 7;111(22):2881-8. doi: 10.1161/CIRCULATIONAHA.104.475194. Epub 2005 May 31.
Atrial fibrillation (AF) is common after cardiac surgery. Abnormal conduction is an important substrate for AF. We hypothesized that atrial inflammation alters atrial conduction properties.
Normal mongrel canines (n=24) were divided into 4 groups consisting of anesthesia alone (control group); pericardiotomy (pericardiotomy group); lateral right atriotomy (atriotomy group); and lateral right atriotomy with antiinflammatory therapy (methylprednisolone 2 mg/kg per day) (antiinflammatory group). Right atrial activation was examined 3 days after surgery. Inhomogeneity of conduction was quantified by the variation of maximum local activation phase difference. To initiate AF, burst pacing was performed. Myeloperoxidase activity and neutrophil cell infiltration in the atrial myocardium were measured to quantify the degree of inflammation. The inhomogeneity of atrial conduction of the atriotomy and pericardiotomy groups was higher than that of the control group (2.02+/-0.10, 1.51+/-0.03 versus 0.96+/-0.08, respectively; P<0.005). Antiinflammatory therapy decreased the inhomogeneity of atrial conduction after atriotomy (1.16+/-0.10; P<0.001). AF duration was longer in the atriotomy and pericardiotomy groups than in the control and antiinflammatory groups (P=0.012). There also were significant differences in myeloperoxidase activity between the atriotomy and pericardiotomy groups and the control group (0.72+/-0.09, 0.41+/-0.08 versus 0.18+/-0.03 DeltaOD/min per milligram protein, respectively; P<0.001). Myeloperoxidase activity of the antiinflammatory group was lower than that of the atriotomy group (0.17+/-0.02; P<0.001). Inhomogeneity of conduction correlated with myeloperoxidase activity (r=0.851, P<0.001).
The degree of atrial inflammation was associated with a proportional increase in the inhomogeneity of atrial conduction and AF duration. This may be a factor in the pathogenesis of early postoperative AF. Antiinflammatory therapy has the potential to decrease the incidence of AF after cardiac surgery.
心房颤动（AF）在心脏手术后很常见。异常传导是AF的重要基质。我们假设心房炎症会改变心房传导特性。
将24只正常杂种犬分为4组，分别为单纯麻醉组（对照组）；心包切开术组（心包切开术组）；右心房外侧切开术组（切开术组）；以及右心房外侧切开术联合抗炎治疗组（甲基泼尼松龙2mg/kg/天）（抗炎组）。术后3天检查右心房激活情况。通过最大局部激活相位差的变化来量化传导的不均匀性。为诱发AF，进行猝发起搏。测量心房心肌中的髓过氧化物酶活性和中性粒细胞浸润情况，以量化炎症程度。切开术组和心包切开术组的心房传导不均匀性高于对照组（分别为2.02±0.10、1.51±0.03对0.96±0.08；P<0.005）。抗炎治疗降低了切开术后心房传导的不均匀性（1.16±0.10；P<0.001）。切开术组和心包切开术组的AF持续时间比对照组和抗炎组更长（P=0.012）。切开术组和心包切开术组与对照组之间的髓过氧化物酶活性也存在显著差异（分别为0.72±0.09、0.41±0.08对0.18±0.03ΔOD/分钟/毫克蛋白；P<0.001）。抗炎组的髓过氧化物酶活性低于切开术组（0.17±0.02；P<0.001）。传导不均匀性与髓过氧化物酶活性相关（r=0.851，P<0.001）。
心房炎症程度与心房传导不均匀性和AF持续时间的成比例增加相关。这可能是术后早期AF发病机制中的一个因素。抗炎治疗有可能降低心脏手术后AF的发生率。
