How to use MRI in cardiac disease with diastolic dysfunction?

Left ventricular (LV) diastolic dysfunction (DD) is an initially asymptomatic condition that can progress to heart failure, either with preserved or reduced ejection fraction. As such, DD is a growing public health problem. Impaired relaxation, the first stage of DD, is associated with altered LV filling. With progression, reducing LV compliance leads to restrictive cardiomyopathy. While cardiac magnetic resonance (CMR) imaging is the reference for LV systolic function assessment, transthoracic echocardiography (TTE) with Doppler flow measurements remains the standard for diastolic function assessment. Rather than simply replicating TTE measurements, CMR should complement and further advance TTE findings. We provide herein a step-by-step review of CMR findings in DD as well as imaging features which may help identify the underlying cause.

CT annulus sizing prior to transcatheter aortic valve replacement (TAVR): evaluation of free-breathing versus breath-holding acquisition.

OBJECTIVES: To assess feasibility and accuracy of aortic annulus measurements using cardiac computed tomography angiography (CTA) performed during free-breathing prior to transcatheter aortic valve replacement (TAVR). MATERIALS AND METHODS: Sixty consecutive TAVR candidates underwent free-breathing wide-detector cardiac CTA, followed by a percutaneous valve replacement. For each, a theoretical valve size was suggested through CT measurements of the annulus, then compared to the size of the actual implanted transcatheter heart valve (THV). The procedural success and the 30-day outcomes were collected. Image quality of the annulus was also studied according to subjective and objective criteria. Data of a control group of 60 patients previously evaluated on breath-holding were also evaluated. RESULTS: A total of 120 patients (mean age, 83 years ± 7, 60 men) were evaluated. All CT acquisitions provided sufficient image quality allowing precise annulus measurements. Mean attenuation (p < 0.001) and image noise (p = 0.01) were higher in the free-breathing group, while image quality was comparable (p = 0.36). The agreement rate between CT-suggested valve size and THV implanted size was comparable, estimated at 87% (κ = 0.79, 95%CI 0.566, 0.908) on free-breathing vs. 82% (κ = 0.78, 95%CI 0.634, 0.904) on breath-holding. The procedure was successful for all patients without increase in 30-day mortality or adverse events. CONCLUSIONS: Free-breathing cardiac CTA allows accurate aortic annulus measurements without compromising image quality or patients' outcome after TAVR. Elderly patients experiencing dyspnea, discomfort, or hearing loss that could prevent proper breath-holding should not be excluded from CT prior to TAVR. CLINICAL RELEVANCE STATEMENT: To decrease elderly patients' discomfort, MDCT evaluation prior to transcatheter aortic valve replacement (TAVR) may be performed on quiet breathing with no significant impact on the outcome. KEY POINTS: • Adhering to CT breathing commands can be challenging for patients with dyspnea, hearing impairment, agitation, or pulmonary diseases. • Free-breathing cardiac CT may be an alternative to breath-holding for patients unable to follow the breathing commands. • Wide-detector CT acquisition on free-breathing does not impair annulus measurements and prosthesis sizing in patients scheduled for TAVR.