BackgroundThe purpose of the study was to compare the accuracy and evaluation time of quantifying left ventricular (LV), left atrial (LA) volume and LV mass using short axis (SAX) and long axis (LAX) methods when using cardiovascular magnetic resonance (CMR).Materials and methodsWe studied 12 explanted canine hearts and 46 patients referred for CMR (29 male, age 47 ± 18 years) in a clinical 1.5 T CMR system, using standard cine sequences. In standard short axis stacks of various slice thickness values in dogs and 8 mm slice thickness (gap 2 mm) in patients, we measured LV volumes using reference slices in a perpendicular, long axis orientation using certified software. Volumes and mass were also measured in six radial long axis (LAX) views.LV parameters were also assessed for intra- and inter-observer variability. In 24 patients, we also analyzed reproducibility and evaluation time of two very experienced (> 10 years of CMR reading) readers for SAX and LAX.ResultsIn the explanted dog hearts, there was excellent agreement between ex vivo data and LV mass and volume data as measured by all methods for both, LAX (r2 = 0.98) and SAX (r2 = 0.88 to 0.98). LA volumes, however, were underestimated by 13% using the LAX views. In patients, there was a good correlation between all three assessed methods (r2 ≥ 0.95 for all). In experienced clinical readers, left-ventricular volumes and ejection fraction as measured in LAX views showed a better inter-observer reproducibility and a 27% shorter evaluation time.ConclusionWhen compared to an ex vivo standard, both, short axis and long axis techniques are highly accurate for the quantification of left ventricular volumes and mass. In clinical settings, however, the long axis approach may be more reproducible and more time-efficient. Therefore, the rotational long axis approach is a viable alternative for the clinical assessment of cardiac volumes, function and mass.

A 56-year-old woman began to have pain and redness of the left leg the day after a six-hour car ride. Two days later she was found to have erythema and tenderness on the medial aspect of the left knee and moderate pitting edema of the left ankle. The remainder of the examination was unremarkable. She had no history of deep venous thrombosis. Both her parents, however, had a history of deep venous thrombosis. Despite treatment with warm compresses, aspirin, and elevation of the leg, the pain and erythema increased. A palpable, ropelike cord was present from the left medial malleolus to the groin. Duplex Doppler ultrasonography revealed thrombosis of the greater saphenous vein, with no extension into the deep venous system. Despite anticoagulation with heparin, a vague, substernal chest pain developed that was unrelieved by nitroglycerin. Cardiac enzymes, electrocardiographic findings, and arterial blood gas levels remained normal. The results of ventilationperfusion scanning were indeterminate for pulmonary embolism, and a pulmonary arteriogram was negative. Repeated duplex Doppler ultrasonography 5, 10, and 25 days after presentation showed no extension of the thrombus into the deep venous system. Studies revealed that the patient had lupus anticoagulant, and a diagnosis of primary antiphospholipid-antibody syndrome was made. Other studies for thrombophilic tendencies, including tests for factor V Leiden and protein C and S deficiencies, were negative. Two weeks after the initiation of treatment with warfarin, the international normalized ratio was 3.4 and the patient's symptoms had resolved. Follow-up at three months showed no recurrence.