Histologic assessment of lower extremity deep vein thrombus from patients undergoing percutaneous mechanical thrombectomy.

BACKGROUND: Histologic analyses of deep vein thrombi (DVTs) have used autopsy samples and animal models. To the best of our knowledge, no previous study has reported on thrombus composition after percutaneous mechanical extraction. Because elements of chronicity and organization render thrombus resistant to anticoagulation and thrombolysis, a better understanding of clot evolution could inform therapy. METHODS: We performed a histologic evaluation of DVTs from consecutive patients who had undergone mechanical thrombectomy for extensive iliofemoral DVTs using the Clottriever/Flowtriever device (Inari Medical, Irvine, Calif). The DVTs were scored using a semiquantitative method according to the degree of fibrosis (collagen deposition on trichrome staining) and organization (endothelial growth with capillaries and fibroblastic penetration). RESULTS: Twenty-three specimens were available for analysis, with 20 presenting as acute DVT (≤14 days from symptom onset). Of the 23 patients, 11 (48%) had had >5% fibrosis (ie, collagen deposition) and 14 (61%) had had >5% organization (ie, endothelial growth, capillaries, fibroblasts). Four patients with acute DVT had had ≥25% organized thrombus and two had had ≥25% collagen deposition. Of the 20 patients with acute DVT, 40% had had >5% fibrosis and 55% had had >5% organization. The acuity of DVT did not correlate with the amount of fibrosis or organizing scores. CONCLUSIONS: A large proportion of patients with acute DVT will have histologic elements of chronicity and fibrosis. A better understanding of the relationship between such elements and the response to anticoagulant agents and fibrinolytic drugs could inform our approach to therapy.

Sex-Based Disparities in Incidence, Treatment, and Outcomes of Cardiac Arrest in the United States, 2003-2012.

BACKGROUND: Recent studies have shown improving survival after cardiac arrest. However, data regarding sex-based disparities in treatment and outcomes after cardiac arrest are limited. METHODS AND RESULTS: We performed a retrospective analysis of all patients suffering cardiac arrest between 2003 and 2012 using the Nationwide Inpatient Sample database. Annual rates of cardiac arrest, rates of utilization of coronary angiography/percutaneous coronary interventions/targeted temperature management, and sex-based outcomes after cardiac arrest were examined. Among a total of 1 436 052 discharge records analyzed for cardiac arrest patients, 45.4% (n=651 745) were females. Women were less likely to present with ventricular tachycardia/ventricular fibrillation arrests compared with men throughout the study period. The annual rates of cardiac arrests have increased from 2003 to 2012 by 14.0% (Ptrend<0.001) and ventricular tachycardia/ventricular fibrillation arrests have increased by 25.9% (Ptrend<0.001). Women were less likely to undergo coronary angiography, percutaneous coronary interventions, or targeted temperature management in both ventricular tachycardia/ventricular fibrillation and pulseless electrical activity/asystole arrests. Over a 10-year study period, there was a significant decrease in in-hospital mortality in women (from 69.1% to 60.9%, Ptrend<0.001) and men (from 67.2% to 58.6%, Ptrend<0.001) after cardiac arrest. In-hospital mortality was significantly higher in women compared with men (64.0% versus 61.4%; adjusted odds ratio 1.02, P<0.001), particularly in the ventricular tachycardia/ventricular fibrillation arrest cohort (49.4% versus 45.6%; adjusted odds ratio 1.11, P<0.001). CONCLUSIONS: Women presenting with cardiac arrests are less likely to undergo therapeutic procedures, including coronary angiography, percutaneous coronary interventions, and targeted temperature management. Despite trends in improving survival after cardiac arrest over 10 years, women continue to have higher in-hospital mortality when compared with men.

Coronary CT angiography versus myocardial perfusion imaging for near-term quality of life, cost and radiation exposure: a prospective multicenter randomized pilot trial.

BACKGROUND: Clinical outcomes and resource utilization after coronary computed tomography angiography (CTA) versus myocardial perfusion single-photon emission CT (MPS) in patients with stable angina and suspected coronary artery disease (CAD) has not been examined. OBJECTIVE: We determined the near-term clinical effect and resource utilization after cardiac CTA compared with MPS. METHODS: We randomly assigned 180 patients (age, 57.3 ± 9.8 years; 50.6% men) presenting with stable chest pain and suspected CAD at 2 sites to initial diagnostic evaluation by coronary CTA (n = 91) or MPS (n = 89). The primary outcome was near-term angina-specific health status; the secondary outcomes were incident medical and invasive treatments for CAD, CAD health care costs, and estimated radiation dose. RESULTS: No patients experienced myocardial infarction or death with 98.3% follow-up at 55 ± 34 days. Both arms experienced comparable improvements in angina-specific health status. Patients who received coronary CTA had increased incident aspirin (22% vs 8%; P = 0.04) and statin (7% vs -3.5%; P = 0.03) use, similar rates of CAD-related hospitalization, invasive coronary angiography, noninvasive cardiac imaging tests, and increased revascularization (8% vs 1%; P = 0.03). Coronary CTA had significantly lower total costs ($781.08 [interquartile range (IQR), $367.80-$4349.48] vs $1214.58 [IQR, $978.02-$1569.40]; P < 0.001) with no difference in induced costs. Coronary CTA had a significantly lower total estimated effective radiation dose (7.4 mSv [IQR, 5.0-14.0 mSv] vs 13.3 mSv [IQR, 13.1-38.0 mSv]; P < 0.0001) with no difference in induced radiation. CONCLUSION: In a pilot randomized controlled trial, patients with stable CAD undergoing coronary CTA and MPS experience comparable improvements in near-term angina-related quality of life. Compared with MPS, coronary CTA evaluation is associated with more aggressive medical therapy, increased coronary revascularization, lower total costs, and lower effective radiation dose.

Noninvasive assessment of myocardial viability in a small animal model: comparison of MRI, SPECT, and PET.

Acute myocardial infarction (AMI) research relies increasingly on small animal models and noninvasive imaging methods such as MRI, single-photon emission computed tomography (SPECT), and positron emission tomography (PET). However, a direct comparison among these techniques for characterization of perfusion, viability, and infarct size is lacking. Rats were studied within 18-24 hr post AMI by MRI (4.7 T) and subsequently (40-48 hr post AMI) by SPECT ((99)Tc-MIBI) and micro-PET ((18)FDG). A necrosis-specific MRI contrast agent was used to detect AMI, and a fast low angle shot (FLASH) sequence was used to acquire late enhancement and functional images contemporaneously. Infarcted regions showed late enhancement, whereas corresponding radionuclide images had reduced tracer uptake. MRI most accurately depicted AMI, showing the closest correlation and agreement with triphenyl tetrazolium chloride (TTC), followed by SPECT and PET. In some animals a mismatch of reduced uptake in normal myocardium and relatively increased (18)FDG uptake in the infarct border zone precluded conventional quantitative analysis. We performed the first quantitative comparison of MRI, PET, and SPECT for reperfused AMI imaging in a small animal model. MRI was superior to the other modalities, due to its greater spatial resolution and ability to detect necrotic myocardium directly. The observed (18)FDG mismatch likely represents variable metabolic conditions between stunned myocardium in the infarct border zone and normal myocardium and supports the use of a standardized glucose load or glucose clamp technique for PET imaging of reperfused AMI in small animals.