title: Relationship of maximum rate of pressure rise between aorta and left ventricle in pediatric patients. Implication for ventricular-vascular interaction with the potential for noninvasive determination of left ventricular contractility.
abstract: BACKGROUND
  The maximum rate of the ventricular pressure rise (dp/dt(max)) provides a reliable measure of ventricular contractility. However, its estimation requires invasive measurement of left ventricular (LV) pressure, limiting its bedside clinical applicability. In the present study, 2 hypotheses were tested: (1)that the ratio of dp/dt(max) between the aorta (Ao) and LV is consistent among patients despite marked differences in underlying cardiac disease, contractile state and heart rate when vascular mechanical and loading properties are taken into account, and (2)that using such a relationship, LV dp/dt(max) can be estimated from Ao dp/dt(max), potentially providing a method of noninvasive determination of LV contractility.
  
  
  RESULTS
  Data from 30 control children and 45 pediatric patients with various cardiovascular diseases revealed that the characteristic impedance (Zc) and mean arterial pressure were significant determinants of the Ao-LV dp/dt(max) relationship in both control and disease groups. LV dp/dt(max) estimated using the regression obtained in the control children (Ao dp/dt(max/)LV dp/dt(max) = 0.64+1.45*10(-4)*Zc-3.73*10(-3)*MAP, r=0.87) correlated well with the measured LV dp/dt(max) in the disease group, including measurements taken after dobutamine and atrial pacing (r=0.89).
  
  
  CONCLUSIONS
  Ao dp/dt(max) and LV dp/dt(max) are closely correlated through the vascular loading properties and LV dp/dt(max) can be derived from Ao dp/dt(max), which has potential as a noninvasive method of determining LV contractility.
authors: Department of Pediatric Cardiology, International Medical Center, Saitama Medical University, Hidaka, Saitama, Japan.
authors: Satoshi
authors: S
authors: Masutani
authors: Yoichi
authors: Y
authors: Iwamoto
authors: Hirotaka
authors: H
authors: Ishido
authors: Hideaki
authors: H
authors: Senzaki
mesh_terms: D001011:Aorta / Q000503:physiopathology*; D001794:Blood Pressure; D006328:Cardiac Catheterization; D002304:Cardiac Pacing, Artificial; D002316:Cardiotonic Agents; D016022:Case-Control Studies; D002648:Child; D002675:Child, Preschool; D004280:Dobutamine; D005260:Female; D006330:Heart Defects, Congenital / Q000175:diagnosis* / Q000503:physiopathology; D006339:Heart Rate; D006801:Humans; D007700:Kinetics; D016014:Linear Models; D008297:Male; D008955:Models, Cardiovascular; D009080:Mucocutaneous Lymph Node Syndrome / Q000503:physiopathology; D009200:Myocardial Contraction; D011237:Predictive Value of Tests; D016277:Ventricular Function, Left; D017725:Ventricular Pressure
chemical_list: D002316:Cardiotonic Agents; D004280:Dobutamine