Prevalence and characterization of pulmonary vein variants in patients with atrial fibrillation determined using 3-dimensional computed tomography.

Although several branching patterns of pulmonary veins (PVs) were reported, their prevalence and characterization were not sufficiently clarified. Multislice computed tomography was performed in 428 patients who underwent catheter ablation for drug-refractory atrial fibrillation. Size and branching pattern of PVs were analyzed. A typical pattern of 4 PVs with 4 separate ostia was found in 326 patients (76%). However, a common PV trunk, defined as a PV with coalescence of superior and inferior PVs > or =1.5 cm proximal to the junction with the left atrium, was found on the left side in 34 patients (8%) and right side in 3 patients (0.76%). A discrete middle PV was found on the right side in 54 patients (13%) and left side in 9 patients (2%). A right top PV, defined as an anomalous insertion of a branch of the right superior PV into the left atrial body, was also found in 16 patients (4%). In conclusion, 24% of our patients with atrial fibrillation had PV anomalies and 3% had coexistence of 2 PV variants, indicating that PV variants are not rare.

Usefulness of virtual histology intravascular ultrasound to predict distal embolization for ST-segment elevation myocardial infarction.

OBJECTIVES: We aimed to predict the high-risk plaque of distal embolization after stent deployment in patients with acute ST-segment elevation myocardial infarction (STEMI) with Virtual Histology intravascular ultrasound (VH-IVUS) (Volcano Therapeutics, Inc., Rancho Cordova, California). BACKGROUND: Distal embolization during primary percutaneous coronary intervention (PCI) carries a poor prognosis in patients with STEMI. However, it is unclear which plaque characteristics cause distal embolization after stent deployment. METHODS: A total of 71 patients with STEMI were included prospectively. All patients underwent primary PCI within 12 h of symptom onset. After crossing the lesion with a guidewire and performing thrombectomy with an aspiration catheter, VH-IVUS of the infarct-related vessel was performed. Stent deployment was then undertaken without embolic protection. ST-segment re-elevation (STR) was used to evaluate distal embolization. Correlations among plaque characteristics, morphology, and distal embolization were analyzed. RESULTS: The STR after stent deployment was observed in 11 patients (STR group, 15.5%). Necrotic core volume was significantly higher in the STR group than in the non-STR group (32.9 +/- 14.1 mm3 vs. 20.4 +/- 19.1 mm3, p < 0.05). Total plaque volume was similar in both groups. On receiver-operating characteristic analysis, necrotic core volume clearly predicted STR after stent deployment as compared with fibrous, fibro-lipid, dense calcium, and total plaque volumes. The necrotic core volume that was best predictive for STR was 33.4 mm3, with a sensitivity of 81.7% and a specificity of 63.6%. CONCLUSIONS: Virtual Histology IVUS is a useful means of predicting the risk of distal embolization after primary stent deployment in patients with STEMI.