title: Determinants and prognostic implications of the negative diastolic pulmonary pressure gradient in patients with pulmonary hypertension due to left heart disease.
abstract: The diastolic pulmonary pressure gradient (DPG) has recently been introduced as a specific marker of combined pre-capillary pulmonary hypertension (Cpc-PH) in left heart disease (LHD). However, its diagnostic and prognostic superiority compared with traditional haemodynamic indices has been challenged lately. Current recommendations explicitly denote that in the normal heart, DPG values are greater than zero, with DPG ≥7 mmHg indicating Cpc-PH. However, clinicians are perplexed by the frequent observation of DPG <0 mmHg (DPGNEG), as its physiological explanation and clinical impact are unclear to date. We hypothesized that large V-waves in the pulmonary artery wedge pressure (PAWP) curve yielding asymmetric pressure transmission might account for DPGNEGand undertook this study to clarify the physiological and prognostic implications of DPGNEG.
  
  
  
  Right heart catheterization and echocardiography were performed in 316 patients with LHD due to primary myocardial dysfunction or valvular disease. A total of 256 patients had PH-LHD, of whom 48% demonstrated DPGNEG. The V-wave amplitude inversely correlated with DPG (r = -0.45, P < 0.001) in patients with low pulmonary vascular resistance (PVR), but not in those with elevated PVR (P > 0.05). Patients with large V-waves had negative and lower DPG than those without augmented V-waves (P < 0.001) despite similar PVR (P >0.05). Positive, but normal DPG (0-6 mmHg) carried a worse 2-year prognosis for death and/or heart transplantation than DPGNEG(hazard ratio 2.97; P < 0.05).
  
  
  
  Our results advocate against DPGNEGconstituting a measurement error. We propose that DPGNEGcan partially be ascribed to large V-waves and carries a better prognosis than DPG within the normal positive range.
authors.affiliation: Heart and Vascular Center, Semmelweis University, Budapest, Hungary.
authors.forename: Anikó Ilona
authors.initials: AI
authors.lastname: Nagy
authors.affiliation: School for Technology and Health, Royal Institute of Technology, Stockholm, Sweden.|Sri Sathya Sai Institute of Higher Medical Sciences, Bangalore, India.
authors.forename: Ashwin
authors.initials: A
authors.lastname: Venkateshvaran
authors.affiliation: Heart and Vascular Center, Semmelweis University, Budapest, Hungary.
authors.forename: Béla
authors.initials: B
authors.lastname: Merkely
authors.affiliation: Department of Cardiology, Karolinska University Hospital, Stockholm, Sweden.|Department of Medicine, Karolinska Institutet, Stockholm, Sweden.
authors.forename: Lars H
authors.initials: LH
authors.lastname: Lund
authors.affiliation: Department of Cardiology, Karolinska University Hospital, Stockholm, Sweden.|Department of Medicine, Karolinska Institutet, Stockholm, Sweden.
authors.forename: Aristomenis
authors.initials: A
authors.lastname: Manouras
mesh_terms: D000328:Adult; D000368:Aged; D006328:Cardiac Catheterization; D003971:Diastole; D004452:Echocardiography; D005260:Female; D006333:Heart Failure / Q000150:complications / Q000000981:diagnostic imaging / Q000503:physiopathology*; D016027:Heart Transplantation; D006801:Humans; D006976:Hypertension, Pulmonary / Q000000981:diagnostic imaging / Q000209:etiology / Q000503:physiopathology*; D008297:Male; D008875:Middle Aged; D009026:Mortality; D011379:Prognosis; D011446:Prospective Studies; D011669:Pulmonary Wedge Pressure / Q000502:physiology*; D014655:Vascular Resistance / Q000502:physiology; D018487:Ventricular Dysfunction, Left / Q000150:complications / Q000000981:diagnostic imaging / Q000503:physiopathology*
keywords: Diastolic pressure gradient; Pulmonary hypertension; V-wave