title: An easy and reproducible parameter for the assessment of the pressure gradient in patients with aortic stenosis disease: A magnetic resonance study.
abstract: OBJECTIVE
  Cardiovascular magnetic resonance (CMR) has been increasingly used as an alternative method to evaluate the severity of aortic stenosis. The aim of our study was to evaluate whether the indirect measurement of the aortic gradient (Calc-PG), derived from Gorlin's formula, is a reproducible parameter for gradient assessment. Then, we evaluated if this parameter is correlated with left ventricular hypertrophy, considered as a marker of severity of aortic stenosis, better than phase-contrast sequences-derived pressure gradient (PC-PG) and aortic valve area.
  
  
  METHODS
  Forty-one patients with isolated aortic stenosis underwent CMR. Calc-PG was obtained from the formula (cardiac output/aortic valve area)(2), and it was compared to PC-PG.
  
  
  RESULTS
  We found that the Calc-PG has higher correlation with left ventricle mass than PC-PG (r(2) 0.44, p<0.001 vs. r(2) 0.26, p<0.01), also after multivariate analysis adjusting for age, gender and hypertension (p<0.001). Furthermore, Calc-PG was more reproducible than PC-PG. The receiver operating characteristic comparison curve analysis showed that Calc-PG has a significantly higher ability to describe the presence of left ventricular hypertrophy than PC-PG (area under the curve 0.85, 95% CI 0.70-0.94, p<0.0001 vs. 0.74, 95% CI 0.58-0.87, p=0.03).
  
  
  CONCLUSIONS
  We propose that transaortic gradient indirectly calculated by using the simplified Gorlin's equation could be an alternative method to assess the severity of aortic stenosis.
authors.affiliation: Carnegie Hill Radiology, New York, NY, USA; Department of Radiology, University "La Sapienza," Sant'Andrea Hospital, Rome, Italy. Electronic address: valevale2012@hotmail.com.
authors.forename: Valentina
authors.initials: V
authors.lastname: Valenti
authors.affiliation: IRCCS Neuromed, Pozzilli, IS, Italy.
authors.forename: Sebastiano
authors.initials: S
authors.lastname: Sciarretta
authors.affiliation: Carnegie Hill Radiology, New York, NY, USA.
authors.forename: Matt
authors.initials: M
authors.lastname: Levin
authors.affiliation: Carnegie Hill Radiology, New York, NY, USA.
authors.forename: Leon
authors.initials: L
authors.lastname: Shubayev
authors.affiliation: Carnegie Hill Radiology, New York, NY, USA.
authors.forename: Sophia
authors.initials: S
authors.lastname: Edelstein
authors.affiliation: Carnegie Hill Radiology, New York, NY, USA; Schulich Heart Centre, Sunnybrook Health Sciences Centre, University of Toronto, Toronto, ON, Canada.
authors.forename: Mohammad I
authors.initials: MI
authors.lastname: Zia
authors.affiliation: IRCCS Neuromed, Pozzilli, IS, Italy; Division of Cardiology, Department of Molecular and Clinical Medicine, Sant'Andrea Hospital, University "La Sapienza", Rome, Italy.
authors.forename: Speranza
authors.initials: S
authors.lastname: Rubattu
authors.affiliation: IRCCS Neuromed, Pozzilli, IS, Italy; Division of Cardiology, Department of Molecular and Clinical Medicine, Sant'Andrea Hospital, University "La Sapienza", Rome, Italy.
authors.forename: Massimo
authors.initials: M
authors.lastname: Volpe
authors.affiliation: Department of Cardiovascular Medicine, Morristown Medical Center, Morristown, NJ, USA.
authors.forename: Seth
authors.initials: S
authors.lastname: Uretsky
authors.affiliation: Carnegie Hill Radiology, New York, NY, USA.
authors.forename: Steven D
authors.initials: SD
authors.lastname: Wolff
mesh_terms: D000368:Aged; D000369:Aged, 80 and over; D001021:Aortic Valve / Q000473:pathology / Q000503:physiopathology; D001024:Aortic Valve Stenosis / Q000175:diagnosis* / Q000473:pathology / Q000503:physiopathology*; D002302:Cardiac Output / Q000502:physiology; D005260:Female; D006801:Humans; D017379:Hypertrophy, Left Ventricular / Q000473:pathology / Q000503:physiopathology*; D008279:Magnetic Resonance Imaging / Q000379:methods*; D008297:Male; D008875:Middle Aged; D008955:Models, Cardiovascular; D015999:Multivariate Analysis; D011312:Pressure; D012189:Retrospective Studies; D012720:Severity of Illness Index; D013318:Stroke Volume / Q000502:physiology; D020257:Ventricular Remodeling / Q000502:physiology
keywords: Aortic stenosis; Cardiac magnetic resonance; Gorlin's formula; Hakki's formula; Pressure gradient