Management of patients with hip fracture receiving anticoagulation: What are we doing in Canada?

BACKGROUND: Direct oral anticoagulants (DOACs) are rapidly replacing warfarin for therapeutic anticoagulation; however, many DOACs are irreversible and may complicate bleeding in emergent situations such as hip fracture. In this setting, there is a lack of clear guidelines for the timing of surgery. The purpose of this study was to evaluate the current practices of Canadian orthopedic surgeons who manage patients with hip fracture receiving anticoagulation. METHODS: In January-March 2018, we administered a purpose-specific cross-sectional survey to all currently practising orthopedic surgeons in Canada who had performed hip fracture surgery in 2017. The survey evaluated approaches to decision-making and timing of surgery in patients with hip fracture receiving anticoagulation. RESULTS: A total of 280 surgeons representing a mix of academic and community practice, seniority and fellowship training responded. Nearly one-quarter of respondents (66 [23.4%]) were members of the Canadian Orthopaedic Trauma Society (COTS). Almost three-quarters (206 [73.6%]) felt that adequate clinical guidelines for patients with hip fracture receiving anticoagulation did not exist, and 177 (61.9%) indicated that anesthesiology or internal medicine had a greater influence on the timing of surgery than the attending surgeon. A total of 117/273 respondents (42.9%) indicated that patients taking warfarin should have immediate surgery (with or without reversal), compared to 63/270 (23.3%) for patients taking a DOAC (p < 0.001). Members of COTS were more likely than nonmembers to advocate for immediate surgery in all patients (p < 0.05). CONCLUSION: There is wide variability in Canada in the management of patients with hip fracture receiving anticoagulation. Improved multidisciplinary communication, prospectively evaluated treatment guidelines and focus on knowledge translation may add clarity to this issue. LEVEL OF EVIDENCE: IV.

Reliability and reproducibility of cardiac MRI quantification of peak exercise function with long-axis views.

The conventional approach to cardiac magnetic resonance (CMR) involving breath holds, electrocardiography-gating, and acquisition of a short-axis (SAX) image stack, introduces technical and logistical challenges for assessing exercise left ventricular (LV) function. Real-time, free-breathing CMR acquisition of long-axis (LAX) images overcomes these issues and also enables assessment of global longitudinal strain (GLS). We evaluated the reliability of a free-breathing LAX approach compared to the standard SAX approach and the reproducibility of free-breathing LAX. LV SAX (contiguous stack) and LAX (two-chamber and four-chamber) 3T CMR cine images were acquired four times within one scan in 32 women with cardiovascular risk factors (56±10 years, 28±4 kg/m2) as follows: 1) resting, gated-segmented, end-expiration breath-hold; 2) resting, real-time, free-breathing; 3) test-retest set of resting, real-time, free-breathing; 4) peak exercise (incremental-to-maximum, in-magnet, stepper test), real-time, free-breathing. A second scan was performed within one week in a subset (n = 5) to determine reproducibility of peak exercise measures. Reliability and agreement of the free-breathing LAX approach with the conventional SAX approach were assessed by intraclass correlation coefficient (ICC) and Bland-Altman plots, respectively. Normal control GLS reserve was also acquired in a separate set of 12 young, healthy control women (25±4 years, 22±2 kg/m2) for comparison. Comparisons of LV volumes and function among all techniques at rest had good-to-excellent reliability (ICC = 0.80-0.96), and excellent reliability between peak exercise free-breathing LAX and SAX evaluations (ICC = 0.92-0.96). Higher resting heart rates with free-breathing acquisitions compared to breath-hold (mean difference, limits of agreement: 5, 1-12 beats per minute) reduced reliability for cardiac output (ICC = 0.67-0.79). Reproducibility of the free-breathing LAX approach was good-to-excellent at rest and peak exercise (ICC = 0.74-0.99). GLS exercise reserve was impaired in older women at cardiovascular risk compared to young healthy women (-4.7±2.3% vs -7.4±2.1%, p = 0.001). Real-time, free-breathing CMR with LAX evaluation provides a reliable and reproducible method to assess rest and peak exercise cardiac function, including GLS.