Anikó Ilona Nagy1, Ashwin Venkateshvaran2,3, Béla Merkely1, Lars H Lund4,5, Aristomenis Manouras4,5. 1. Heart and Vascular Center, Semmelweis University, Budapest, Hungary. 2. School for Technology and Health, Royal Institute of Technology, Stockholm, Sweden. 3. Sri Sathya Sai Institute of Higher Medical Sciences, Bangalore, India. 4. Department of Cardiology, Karolinska University Hospital, Stockholm, Sweden. 5. Department of Medicine, Karolinska Institutet, Stockholm, Sweden.
Abstract
AIMS: 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 DPGNEG and undertook this study to clarify the physiological and prognostic implications of DPGNEG . METHODS AND RESULTS: 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). CONCLUSION: Our results advocate against DPGNEG constituting a measurement error. We propose that DPGNEG can partially be ascribed to large V-waves and carries a better prognosis than DPG within the normal positive range.
AIMS: 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 DPGNEG and undertook this study to clarify the physiological and prognostic implications of DPGNEG . METHODS AND RESULTS: 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). CONCLUSION: Our results advocate against DPGNEG constituting a measurement error. We propose that DPGNEG can partially be ascribed to large V-waves and carries a better prognosis than DPG within the normal positive range.
Authors: Christopher S Johns; James M Wild; Smitha Rajaram; Euan Tubman; David Capener; Charlie Elliot; Robin Condliffe; Athanasios Charalampopoulos; David G Kiely; Andrew J Swift Journal: Radiology Date: 2018-07-03 Impact factor: 29.146