Eva Amalie Nielsen1, Morten Smerup1, Peter Agger1, Jesper Frandsen2, Michael Pedersen3, Steffen Ringgaard3, Peter Vestergaard2, Jens Randel Nyengaard4, Johnnie Bremholm Andersen4, Paul P. Lunkenheimer5, Robert H. Anderson6, Vibeke Hjortdal1
1Department of Cardiothoracic & Vascular Surgery, Aarhus University Hospital, Skejby, Aarhus, Denmark; 2Center for Functionally Integrative Neuroscience, Aarhus University Hospital, Aarhus Sygehus, Aarhus, Denmark; 3MR Research Center, Aarhus University Hospital, Skejby, Aarhus, Denmark; 4Stereology and EM Laboratory and MIND Center, Aarhus University, Aarhus, Denmark; 5Klinik und Poliklinik fr Thorax-, Herz- und Gefsschirurgie, University Mnster, Mnster, Germany; 6Cardiac Unit, Institute of Child Health, University College,, London, UK
The three-dimensional architecture of the myocytes aggregated together making up the right ventricular myocardium (RV) is a major determinant of function. We studied the normal architecture with the arrangement induced by chronic hypertrophy, using diffusion tensor MRI. The architecture is comparable to that found in the left ventricle in terms of endocardial and epicardial angulations of the chains of aggregated myocytes, albeit that the RV lacks the extensive zone of myocytes aggregated in circular fashion in the mid-portion of the left ventricular walls. Without such beneficial architectural remodeling, the porcine RV seems unsuited structurally to sustain a permanent increase in afterload.