title: The relative myocardial blood volume differentiates between hypertensive heart disease and athlete's heart in humans.
abstract: OBJECTIVE
  The adaptation of the myocardial microcirculation in humans to pathologic and physiologic stress has not been examined in vivo so far. We sought to test whether the relative blood volume (rBV) measured by myocardial contrast echocardiography (MCE) can differentiate between left ventricular (LV) hypertrophy (LVH) in hypertensive heart disease and athlete's heart.
  
  
  RESULTS
  Four groups were investigated: hypertensive patients with LVH (n = 15), semi-professional triathletes with LVH (n = 15), professional football players (n = 15), and sedentary control individuals without cardiovascular disease (n = 15). MCE was performed at rest and during adenosine-induced hyperaemia. The rBV (mL mL(-1)), its exchange frequency (beta, min(-1)), and myocardial blood flow (mL min(-1) g(-1)) were derived from steady state and refill sequences of ultrasound contrast agent. Hypertensive patients had lower rBV (0.093 +/- 0.013 mL mL(-1)) than triathletes (0.141 +/- 0.012 mL mL(-1), P < 0.001), football players (0.129 +/- 0.014 mL mL(-1), P < 0.001), and sedentary individuals (0.126 +/- 0.018 mL mL(-1), P < 0.001). Conversely, the exchange frequency (beta) was significantly higher in hypertensive patients (11.3 +/- 3.8 min(-1)) than in triathletes (7.4 +/- 1.8 min(-1)), football players (7.7 +/- 2.3 min(-1)), and sedentary individuals (9.0+/-2.5 min(-1)). An rBV below 0.114 mL mL(-1) distinguished hypertensive patients and triathletes with a sensitivity of 93% and a specificity of 100%.
  
  
  CONCLUSIONS
  Pathologic and physiologic LVH were differentiated non-invasively and accurately by rBV, a measure of vascularisation assessed by MCE.
authors.affiliation: Department of Cardiology, University Hospital Bern, CH-3010 Bern, Switzerland.
authors.forename: Andreas
authors.initials: A
authors.lastname: Indermühle
authors.forename: Rolf
authors.initials: R
authors.lastname: Vogel
authors.forename: Pascal
authors.initials: P
authors.lastname: Meier
authors.forename: Simone
authors.initials: S
authors.lastname: Wirth
authors.forename: Regula
authors.initials: R
authors.lastname: Stoop
authors.forename: Markus G
authors.initials: MG
authors.lastname: Mohaupt
authors.forename: Christian
authors.initials: C
authors.lastname: Seiler
mesh_terms: D000328:Adult; D000704:Analysis of Variance; D001810:Blood Volume / Q000502:physiology; D016022:Case-Control Studies; D004452:Echocardiography; D005260:Female; D006801:Humans; D006973:Hypertension / Q000175:diagnosis* / Q000503:physiopathology; D017379:Hypertrophy, Left Ventricular / Q000175:diagnosis* / Q000503:physiopathology; D008297:Male; D008833:Microcirculation / Q000502:physiology; D010865:Pilot Projects; D013177:Sports; D013314:Stress, Mechanical