title: Arterial pulse wave dynamics after percutaneous aortic valve replacement: fall in coronary diastolic suction with increasing heart rate as a basis for angina symptoms in aortic stenosis.
abstract: BACKGROUND
  Aortic stenosis causes angina despite unobstructed arteries. Measurement of conventional coronary hemodynamic parameters in patients undergoing valvular surgery has failed to explain these symptoms. With the advent of percutaneous aortic valve replacement (PAVR) and developments in coronary pulse wave analysis, it is now possible to instantaneously abolish the valvular stenosis and to measure the resulting changes in waves that direct coronary flow.
  
  
  RESULTS
  Intracoronary pressure and flow velocity were measured immediately before and after PAVR in 11 patients with unobstructed coronary arteries. Using coronary pulse wave analysis, we calculated the intracoronary diastolic suction wave (the principal accelerator of coronary blood flow). To test physiological reserve to increased myocardial demand, we measured at resting heart rate and during pacing at 90 and 120 bpm. Before PAVR, the basal myocardial suction wave intensity was 1.9±0.3×10(-5) W · m(-2) · s(-2), and this increased in magnitude with increasing severity of aortic stenosis (r=0.59, P=0.05). This wave decreased markedly with increasing heart rate (β coefficient=-0.16×10(-4) W · m(-2) · s(-2); P<0.001). After PAVR, despite a fall in basal suction wave (1.9±0.3 versus 1.1±0.1×10(-5) W · m(-2) · s(-2); P=0.02), there was an immediate improvement in coronary physiological reserve with increasing heart rate (β coefficient=0.9×10(-3) W · m(-2) · s(-2); P=0.014).
  
  
  CONCLUSIONS
  In aortic stenosis, the coronary physiological reserve is impaired. Instead of increasing when heart rate rises, the coronary diastolic suction wave decreases. Immediately after PAVR, physiological reserve returns to a normal positive pattern. This may explain how aortic stenosis can induce anginal symptoms and their prompt relief after PAVR. Clinical Trial Registration- URL: http://www.clinicaltrials.gov. Unique identifier: NCT01118442.
authors.affiliation: MRCP, International Centre for Circulatory Health, St. Mary's Campus, Paddington, London, W2 1LA, UK. justin.davies@imperial.ac.uk
authors.forename: Justin E
authors.initials: JE
authors.lastname: Davies
authors.forename: Sayan
authors.initials: S
authors.lastname: Sen
authors.forename: Chris
authors.initials: C
authors.lastname: Broyd
authors.forename: Nearchos
authors.initials: N
authors.lastname: Hadjiloizou
authors.forename: John
authors.initials: J
authors.lastname: Baksi
authors.forename: Darrel P
authors.initials: DP
authors.lastname: Francis
authors.forename: Rodney A
authors.initials: RA
authors.lastname: Foale
authors.forename: Kim H
authors.initials: KH
authors.lastname: Parker
authors.forename: Alun D
authors.initials: AD
authors.lastname: Hughes
authors.forename: Andrew
authors.initials: A
authors.lastname: Chukwuemeka
authors.forename: Roberto
authors.initials: R
authors.lastname: Casula
authors.forename: Iqbal S
authors.initials: IS
authors.lastname: Malik
authors.forename: Ghada W
authors.initials: GW
authors.lastname: Mikhail
authors.forename: Jamil
authors.initials: J
authors.lastname: Mayet
mesh_terms: D000368:Aged; D000369:Aged, 80 and over; D000787:Angina Pectoris / Q000209:etiology* / Q000503:physiopathology; D001021:Aortic Valve / Q000601:surgery*; D001024:Aortic Valve Stenosis / Q000150:complications* / Q000503:physiopathology / Q000601:surgery; D003326:Coronary Circulation; D003971:Diastole; D005260:Female; D006339:Heart Rate; D019918:Heart Valve Prosthesis Implantation / Q000379:methods; D006439:Hemodynamics; D006801:Humans; D017379:Hypertrophy, Left Ventricular / Q000209:etiology; D008297:Male; D011446:Prospective Studies; D011673:Pulsatile Flow