Comparative Quantification of Arterial Lipid by Intravascular Photoacoustic-Ultrasound Imaging and Near-Infrared Spectroscopy-Intravascular Ultrasound.

Intravascular photoacoustic-ultrasound (IVPA-US) imaging and near-infrared spectroscopy-intravascular ultrasound (NIRS-IVUS) are two hybrid modalities that detect arterial lipid, with comparison necessary to understand the relative advantages of each. We performed in vivo and ex vivo IVPA-US imaging of the iliac arteries of Ossabaw swine with metabolic syndrome (MetS) and lean swine to investigate sensitivity for early-stage atherosclerosis. We repeated imaging ex vivo with NIRS-IVUS for comparison to IVPA-US and histology. Both modalities showed significantly greater lipid in MetS vs. lean swine, but only IVPA-US localized the lipid as perivascular. To investigate late-stage atherosclerosis, we performed ex vivo IVPA-US imaging of a human coronary artery with comparison to NIRS-IVUS and histology. Two advanced fibroatheromas were identified, with agreement between IVPA-measured lipid area and NIRS-derived lipid content. As confirmed histologically, IVPA-US has sensitivity to detect lipid content similar to NIRS-IVUS and provides additional depth resolution, enabling quantification and localization of lipid cores within plaques.

Cardiac events after non-cardiac surgery in patients with previous coronary intervention in the drug-eluting stent era.

The peri-operative risk for patients with coronary drug-eluting stents (DES) who subsequently have non-cardiac surgery (NCS) is unclear. We performed this retrospective study of all patients in our institution who had coronary intervention and subsequent NCS from 2003 through December 2008 to evaluate the incidence of major adverse cardiac events (MACE) in patients who received DES compared to those who received bare-metal stents (BMS) or had percutaneous transluminal coronary angioplasty (PTCA) during the same time period. The main outcome measures were 30-day post-operative myocardial infarction, stent thrombosis, target vessel revascularization (TVR) and cardiac death. During the 6-year study period, 1,770 coronary interventions were performed and 238 patients subsequently had NCS in 8 days to 49 months. Eighteen patients had PTCA, 79 BMS and 141 DES. Acute myocardial infarction occurred in 1 patient who had PTCA, 2 who had BMS and 14 who had DES (p = 0.10). Stent thrombosis occurred in 6 patients who had DES and none who had BMS (p = 0.09). Seven patients who had DES had TVR compared to 1 patient who had BMS and none who had PTCA (p = 0.41). Cardiac mortality occurred in 2 patients who had DES and none who had PTCA or BMS (p = 0.35). In conclusion, the 30-day MACE in patients who received coronary DES and undergone NCS were not significantly different compared to those who received BMS or had PTCA only, with a trend toward higher stent thrombosis in the DES group.