Strategies to safely rule out pulmonary embolism in COVID-19 outpatients: a multicenter retrospective study.

OBJECTIVES: The objective was to define a safe strategy to exclude pulmonary embolism (PE) in COVID-19 outpatients, without performing CT pulmonary angiogram (CTPA). METHODS: COVID-19 outpatients from 15 university hospitals who underwent a CTPA were retrospectively evaluated. D-Dimers, variables of the revised Geneva and Wells scores, as well as laboratory findings and clinical characteristics related to COVID-19 pneumonia, were collected. CTPA reports were reviewed for the presence of PE and the extent of COVID-19 disease. PE rule-out strategies were based solely on D-Dimer tests using different thresholds, the revised Geneva and Wells scores, and a COVID-19 PE prediction model built on our dataset were compared. The area under the receiver operating characteristics curve (AUC), failure rate, and efficiency were calculated. RESULTS: In total, 1369 patients were included of whom 124 were PE positive (9.1%). Failure rate and efficiency of D-Dimer > 500 µg/l were 0.9% (95%CI, 0.2-4.8%) and 10.1% (8.5-11.9%), respectively, increasing to 1.0% (0.2-5.3%) and 16.4% (14.4-18.7%), respectively, for an age-adjusted D-Dimer level. D-dimer > 1000 µg/l led to an unacceptable failure rate to 8.1% (4.4-14.5%). The best performances of the revised Geneva and Wells scores were obtained using the age-adjusted D-Dimer level. They had the same failure rate of 1.0% (0.2-5.3%) for efficiency of 16.8% (14.7-19.1%), and 16.9% (14.8-19.2%) respectively. The developed COVID-19 PE prediction model had an AUC of 0.609 (0.594-0.623) with an efficiency of 20.5% (18.4-22.8%) when its failure was set to 0.8%. CONCLUSIONS: The strategy to safely exclude PE in COVID-19 outpatients should not differ from that used in non-COVID-19 patients. The added value of the COVID-19 PE prediction model is minor. KEY POINTS: • D-dimer level remains the most important predictor of pulmonary embolism in COVID-19 patients. • The AUCs of the revised Geneva and Wells scores using an age-adjusted D-dimer threshold were 0.587 (95%CI, 0.572 to 0.603) and 0.588 (95%CI, 0.572 to 0.603). • The AUC of COVID-19-specific strategy to rule out pulmonary embolism ranged from 0.513 (95%CI: 0.503 to 0.522) to 0.609 (95%CI: 0.594 to 0.623).

Cardiac magnetic resonance for assessment of cardiac involvement in Takotsubo syndrome: Do we still need contrast administration?

BACKGROUND: This study evaluated the ability of T1 and T2 mapping cardiovascular magnetic resonance to assess myocardial involvement in Takotsubo syndrome (TTS). We hypothesized that non-contrast mapping techniques can be accurate and sufficient. METHODS: We prospectively analysed 30 patients with TTS and 34 controls. CMR was performed a mean 5 days after the onset of symptoms and after a mean 3 month follow-up. RESULTS: On admission, compared to controls, TTS patients had significantly higher global T2 values (59 ± 8 ms vs 51 ± 4 ms, p < 0.001), native T1 (1053 ± 75 ms vs 960 ± 61 ms, p < 0.001) and extracellular volume (ECV) fraction (29% ± 5 vs 23% ±3, p < 0.001). The sensitivity and specificity for T2 (cut off: 56 ms) were 62% and 97% respectively; for native T1: (cut off 1011 ms) were 72% and 91% respectively; and for ECV (cut off: 27%) were 72% and 97% respectively. Combining T2 and native T1 provided the best sensitivity (91.7%) with a good specificity (88.2%). No patients had late gadolinium enhancement. Segmental analysis showed that T2, native T1 and ECV values were significantly higher in regions with wall motion abnormalities (WMA) compared to normokinetic segments (62 ± 9 ms vs 55 ± 5 ms, p < 0.001; 1060 ± 65 ms vs 1025 ± 56 ms, p = 0.02; and 34% ± 5 vs 29% ± 1, p = 0.02). At follow up, native T1 and ECV values did not normalized. CONCLUSION: In TTS patients, a non-contrast mapping technique provides a high diagnostic accuracy allowing identification of acute and persistent myocardial injury. Segmental analysis showed that myocardial injury is preferably detected in segments with WMA.

[Stroke prevention]. / Prévention de l'AVC ischémique.

Prevention is essential to stroke management because of the high risk of recurrence. Stroke incidence is increased by known risk factors, which can be prevented. Cardiovascular prevention after stroke or TIA also includes aetiology-specific treatment, when it is known. Endovascular treatment is not indicated as a first-line treatment for atheromatous cervical or intracranial stenosis. Endovascular or surgical treatment is not indicated as first-line treatment for cervical arterial dissection because of its minor risk of stroke recurrence.

[Thoracic, abdominal and pelvic hemostatic embolization]. / Embolisation d'hémostase du thorax, de l'abdomen et du pelvis.

Endovascular embolization has become an essential technique for therapeutic management of thoracic, abdominal and pelvic hemorrhage. A multidisciplinary approach is fostered, involving the intensive care unit, surgeons, trained interventional radiologists and radiology technicians, available twenty-four hours a day and seven days a week, with adequate equipment. Computed tomography angiography is required in all but a few patients (postpartum hemorrhage), providing accurate information about the presence of active bleeding and especially its localization. These data allow determination of whether embolization is a reasonable treatment option, ensuring its success, reducing its duration and decreasing the risk of complication and rebleeding.

Galectin-3 predicts response and outcomes after cardiac resynchronization therapy.

BACKGROUND: Cardiac resynchronization therapy (CRT) reduces symptoms, morbidity and mortality in chronic heart failure patients with wide QRS complexes. However, approximately one third of CRT patients are non-responders. Myocardial fibrosis is known to be associated with absence of response. We sought to see whether galectin-3, a promising biomarker involved in fibrosis processes, could predict response and outcomes after CRT. METHODS: Consecutive patients eligible for implantation of a CRT device with a typical left bundle branch block ≥ 120 ms were prospectively included. Serum Gal-3 level, Selvester ECG scoring, and cardiac magnetic resonance with analysis of late gadolinium enhancement (LGE) were ascertained. Response to CRT was defined by a composite endpoint at 6 months: no death, nor hospitalization for major cardiovascular event, and a significant decrease in left ventricular end-systolic volume of 15% or more. RESULTS: Sixty-one patients were included (age 61 ± 5 years, ejection fraction 27 ± 5%), 59% with non-ischemic cardiomyopathy. At 6 months, 49 patients (80%) were considered responders. Responders had a lower percentage of LGE (8 ± 13% vs 22 ± 16%, p = 0.006), and a trend towards lower rates of galectin-3 (16 ± 6 ng/mL vs 19 ± 8 ng/mL, p = 0.13). LGE ≥ 14% and Gal-3 ≥ 22 ng/mL independently predicted response to CRT (OR = 0.17 [0.03-0.62], p = 0.007, and OR = 0.11 [0.02-0.04], p < 0.001, respectively). At 48 months of follow-up, 12 patients had been hospitalized for a major cardiovascular event or had died. Galectin-3 level predicted long-term outcomes (HR = 3.31 [1.00-11.34], p = 0.05). CONCLUSIONS: Gal-3 serum level predicts the response to CRT at 6 months and long-term outcomes in chronic heart failure patients.

Localization of Left Ventricular Lead Electrodes in Relation to Myocardial Scar in Patients Undergoing Cardiac Resynchronization Therapy.

Background The efficacy of cardiac resynchronization therapy may be reduced in the event of pacing within myocardial fibrosis. We aimed to develop a method to determine the anatomical relationships between the left ventricular ( LV ) lead and myocardial fibrosis. Methods and Results In consecutive patients indicated for cardiac resynchronization therapy, cardiovascular magnetic resonance imaging with late gadolinium enhancement assessment was performed before implantation. After implantation, an injected computed tomography scanner ( CT scan) was performed. The 2 imaging techniques were fused to assess the LV lead position relative to myocardial scar. A total of 68 patients were included. Myocardial scar was found in 29 (43%) and was localized in lateral segments in 14 (21%). Scar was significantly associated with male sex, ischemic cardiomyopathy, a Selvester score adapted to left bundle branch block ( LBBB Selvester), and Selvester criteria for localizing lateral fibrosis (V2 S/S' ratio). Image fusion was feasible in all patients. Position within myocardial scar was confirmed for 6 electrodes in 3 patients. Prolonged QRS duration during LV pacing ≥139% predicted electrode positioning within scar tissue (sensitivity, 83%; specificity, 91%; P=0.002). Conclusions In cardiac resynchronization therapy patients, fusion between preimplantation cardiovascular magnetic resonance and a postimplantation injected computed tomography scan is a feasible technique. Prolongation of the QRS duration during LV pacing predicts pacing within myocardial scar. Accurate location of LV lead pacing electrodes on the epicardial surface relative to myocardial scar, either by imaging or ECG analyses, may help improve cardiac resynchronization therapy response in selected patients.

Distally Based Medial Hemisoleus Muscle Flap: Anatomic and Angiographic Study of 18 Lower Limbs.

BACKGROUND: The distally based medial hemisoleus (MHS) flap was found useful for repairing soft-tissue defects of the lower third of the leg; however, its reliability is controversial. We used a combination of static and dynamic techniques to investigate the vascular supply of distally based MHS muscle flaps to better establish their use in repair of lower-third leg defects. METHODS: We performed an anatomic study of 18 cadaver legs. For 6 legs, we performed dynamic angiography, which allowed for obtaining MHS muscle radiographs after pulsed injection of contrast medium in distal pedicles. RESULTS: The mean length of MHS muscle was 25.4 cm, the mean width was 6.9 cm, and the mean surface area was 87.5 cm. A mean of 3 distal posterior tibial vascular pedicles was directly connected to this medial subunit. These pedicles were present in all 18 cadaver legs. We observed complete opacification of the 6 MHS muscles through distal pedicles. Radiography revealed opacification of a vascular path from 1 distal pedicle to 1 proximal vascular pedicle of the MHS muscle. The mean level of this main distal pedicle was 14.5 cm to the tip of the medial malleolus. The level was at 38.2%, on average, from the bottom of the entire tibia. CONCLUSIONS: The distally based MHS muscle flap has constant blood supply, so it could be a useful flap to repair soft-tissue defects of the lower third of the leg. Moreover, knowledge of the average location of the main distal pedicle can help in increasing the use of the distally based MHS flap.

Contribution of magnetic resonance imaging of the wrist and hand to forensic age assessment.

Forensic age estimation of living individuals is a controversial subject because of the imprecision of the available methods which leads to errors. Moreover, young persons are exposed to radiation, without diagnostic or therapeutic advantage. Recently, non-invasive imaging techniques such as magnetic resonance imaging (MRI) have been studied in this context. The aim of this work was to study if the analysis of wrist/hand MRI enabled determination of whether a subject was 18 years old. Two observers retrospectively analyzed metaphyseal-epiphyseal fusion of the distal epiphysis of the radius and the ulna and the base of the first metacarpus in wrist/hand MRI of living people between 9 and 25 years of age. A three-stage scoring system was applied to all epiphyses. Intra- and inter-observer variability was excellent. Staging of the distal radial epiphysis allowed the subjects to be correctly evaluated with regard to the 18-year-old threshold in more than 85 % of cases. Analysis of the radius alone was as good as the analysis of the three epiphyses together. Evaluation of the metaphyseal-epiphyseal fusion of the distal radius in wrist MRI gave good results in forensic age estimation. Wrist MRI could meet ethical expectations with regard to the link between the benefit and risk of practicing radiologic examination on individuals in this context.

Contribution of Antemortem Computed Tomography Findings to Cause of Death Determination: An Unusual Fatal Stroke.

In the case reported here, the antemortem computed tomography scan (CT scan) was essential in the forensic investigation. A 32-year-old man was found fully awake with a facial abrasion, after what seemed to be a car accident. He lost consciousness suddenly one hour after initial management. Successive CT scan showed a facial fracture and a metallic foreign body in the carotid canal associated with an occlusion/dissection of the left internal carotid, a pseudoaneurysm, and a carotid-cavernous fistula. The victim died from a stroke. Autopsy confirmed that the facial abrasion was a gunshot entrance wound, the metallic foreign body being a projectile. Intracranial vascular injuries linked with gunshot wounds are most of the time isolated and due to pelet embolism. The observed vascular injury association has never been described in the existing literature. The CT scan provided a better understanding of the chronology of events that led to death.

Can the Greulich and Pyle method be used on French contemporary individuals?

Forensic age estimation of living individuals has become increasingly important in forensic practice with the constant increase of migration movements to developed countries. The method of Greulich and Pyle is one of the most frequently used methods for age determination. The aim of our study was to verify the reliability of this method on a French contemporary population. We retrospectively analyzed 190 frontal hand and wrist radiographs of living subjects aged between 10 and 19 years (100 males and 90 females) performed in the Radiology Department of the University Hospital of Tours. These radiographs were compared with the Greulich and Pyle atlas to determine the skeletal age (SA) and to compare it to the chronological age (CA). We calculated the coefficient of correlation and the coefficient of determination for each sex group. The SA of our subjects was also inserted in the graphs provided by Greulich and Pyle in their atlas. Intra- and inter-observer variabilities were good, demonstrating the reproducibility and repeatability of the method. The correlation coefficients were high (0.98 for males and 0.93 for females) and comparable with published data. The mean difference between CA and SA was -2.29 months for males and -6.44 months for females, showing an overestimation of CA for both sexes. No statistical difference was found between CA and SA for both male and female samples. We concluded that the method of Greulich and Pyle can be used on a contemporary French population but not without caution because of a tendency for this method to overestimate age. A fully developed hand and wrist does not allow to state that the 18th year of life is completed beyond a reasonable doubt. We recommend using it in association with other methods.

Accuracy of a new method for semi-quantitative assessment of right ventricular ejection fraction by cardiovascular magnetic resonance: right ventricular fractional diameter changes.

OBJECTIVE: Longitudinal shortening is traditionally considered the predominant part of global right ventricular (RV) systolic function. Less attention has been paid to transverse contraction. The aim of this study was to evaluate RV transverse motion by cardiovascular magnetic resonance (CMR) in a large cohort of patients and to assess its relationship with RV ejection fraction (RVEF). STUDY DESIGN: We retrospectively analyzed the CMR scans of 300 patients referred to our center in 2010. RVEF was determined from short axis sequences using the volumetric method. Transverse parameters called RV fractional diameter changes were calculated after measuring RV diastolic and systolic diameters at basal and mid-level in short axis view (respectively FBDC and FMDC). We also measured the tricuspid annular plane systolic excursion (TAPSE) as a longitudinal reference. RESULTS: Our population was divided into 2 groups according to RVEF. 250 patients had a preserved RVEF (>40%) and 50 had a RV dysfunction (RVEF ≤ 40%). Transverse and longitudinal motions were significantly reduced in the group with RV dysfunction (p<.0001). After ROC analysis, areas under the curve for FBDC, FMDC and TAPSE, were respectively 0.79, 0.82 and 0.72, with the highest specificity and sensitivity respectively of 88% and 68% for FMDC (threshold at 20%) for predicting RV dysfunction. FMDC had an excellent negative predictive value of 93%. CONCLUSION: RV fractional diameter changes, especially at the mid-level, appear to be accurate for semi-quantitative assessment of RV function by CMR. A cut-off of 20% for FMDC differentiates patients with a low (EF≤40%) or a preserved RVEF.