title: Pulmonary vascular response to exercise in symptomatic heart failure with reduced ejection fraction and pulmonary hypertension.
abstract: OBJECTIVE
  To study pulmonary vascular response patterns to exercise in heart failure with reduced ejection fraction (HFrEF) and pulmonary hypertension (PH).
  
  
  RESULTS
  In this prospective single-centre cohort study, consecutive symptomatic HFrEF patients (n = 40) with mean pulmonary arterial pressure (MPAP) ≥25 mmHg, pulmonary artery wedge pressure (PAWP) >15 mmHg, and cardiac index <2.5 L/min.m(2) , received protocol-driven titrated sodium nitroprusside (SNP) and diuretics to reach mean arterial blood pressure 65-75 mmHg and PAWP ≤15 mmHg. Patients performed symptom-limited supine bicycle testing under continued SNP administration. Afterwards, SNP was gradually withdrawn, renin-angiotensin system blockers uptitrated, and hydralazine added to maintain haemodynamic targets. Subsequently, bicycle testing was repeated. Patients presented with pulmonary vascular resistance (PVR) = 3.8 ± 1.4 Wood Units at rest, decreasing to 2.9 ± 0.9 Wood Units after decongestion, with PH was completely reversed (MPAP <25 mmHg) in 22%. From rest to maximal exercise, the cardiac index did not change significantly (P = 0.334 under SNP; P-value = 0.552 under oral therapy). A dynamic exercise-induced PVR increase >3.5 Wood Units was noted in 19 patients (48%) under oral therapy vs. five (13%) under SNP. Such exercise-induced PVR increase was associated with a 33% relative decrease in right ventricular stroke work index (P = 0.037).
  
  
  CONCLUSIONS
  Even after thorough decongestion and under continuous afterload reduction, PH secondary to HFrEF is completely reversible in only a minority of patients. Others demonstrate an exercise-induced PVR increase, associated with impaired right ventricular stroke work, which might be ameliorated by nitric oxide donor support.
authors: Department of Cardiology, Ziekenhuis Oost-Limburg, Schiepse Bos 6, 3600, Genk, Belgium; Doctoral school for Medicine and Life Sciences, Hasselt University, Diepenbeek, Belgium.
authors: Frederik H
authors: FH
authors: Verbrugge
authors: Matthias
authors: M
authors: Dupont
authors: Philippe B
authors: PB
authors: Bertrand
authors: Petra
authors: P
authors: Nijst
authors: Lars
authors: L
authors: Grieten
authors: Joseph
authors: J
authors: Dens
authors: David
authors: D
authors: Verhaert
authors: Stefan
authors: S
authors: Janssens
authors: W H Wilson
authors: WH
authors: Tang
authors: Wilfried
authors: W
authors: Mullens
mesh_terms: D000368:Aged; D000369:Aged, 80 and over; D001794:Blood Pressure / Q000502:physiology; D002302:Cardiac Output / Q000502:physiology; D015444:Exercise / Q000502:physiology*; D005260:Female; D006333:Heart Failure / Q000503:physiopathology*; D006801:Humans; D006976:Hypertension, Pulmonary / Q000503:physiopathology*; D008297:Male; D008875:Middle Aged; D009569:Nitric Oxide / Q000378:metabolism; D011446:Prospective Studies; D011651:Pulmonary Artery / Q000502:physiology*; D013318:Stroke Volume / Q000502:physiology*; D014655:Vascular Resistance / Q000502:physiology
chemical_list: D009569:Nitric Oxide
keywords: Exercise test; Nitric oxide; Pulmonary hypertension; Systolic heart failure