How similar are the mice to men? Between-species comparison of left ventricular mechanics using strain imaging

• Published in: PloS one 2012-06, Vol.7 (6), p.e40061-e40061
• Main Authors: Kusunose, Kenya, Penn, Marc S, Zhang, Youhua, Cheng, Yuanna, Thomas, James D, Marwick, Thomas H, Popović, Zoran B
• Format: Article
• Language: English
• Subjects: Adult; Animals; Biology; Biomechanical Phenomena - physiology; Body size; Cardiology; Data collection; Diastole - physiology; Echocardiography; Heart; Heart Ventricles - anatomy & histology; Heart Ventricles - diagnostic imaging; Heart Ventricles - physiopathology; Horses; Humans; Laboratory animals; Laws, regulations and rules; Mammals; Medicine; Mice; Mice, Inbred C57BL; Middle Aged; NMR; Nuclear magnetic resonance; Observer Variation; Rabbits; Rats; Scaling; Species Specificity; Stroke Volume - physiology; Studies; Systole - physiology; Ultrasonography; Velocity; Ventricle; Ventricular Function - physiology; Veterinary Science; Young Adult
• ISSN: 1932-6203; 1932-6203
• DOI: 10.1371/journal.pone.0040061

While mammalian heart size maintains constant proportion to whole body size, scaling of left ventricular (LV) function parameters shows a more complex scaling pattern. We used 2-D speckle tracking strain imaging to determine whether LV myocardial strains and strain rates scale to heart size. We studied 18 mice, 15 rats, 6 rabbits, 12 dogs and 20 human volunteers by 2-D echocardiography. Relationship between longitudinal or circumferential strains/strain rates (S(Long)/SR(Long), S(Circ)/SR(Circ)), and LV end-diastolic volume (EDV) or mass were assessed by the allometric (power-law) equation Y = kM(β). Mean LV mass in individual species varied from 0.038 to 134 g, LV EDV varied from 0.015 to 102 ml, while RR interval varied from 81 to 1090 ms. While S(Long) increased with increasing LV EDV or mass (β values 0.047±0.006 and 0.051±0.005, p