Interventricular septal configuration at mr imaging and pulmonary arterial pressure in pulmonary hypertension.
OBJECTIVE
To investigate whether a relationship exists between septum shape and systolic pulmonary arterial pressure (PAP) in patients with pulmonary hypertension.


METHODS
Study protocol was approved by institutional ethics review committee; all patients gave informed consent. Right-sided heart catheterization with vasodilator testing was performed in 39 adult subjects suspected of having pulmonary hypertension. There were 11 men and 28 women, aged 21-75 years (mean, 46 years). Only two patients showed favorable response to vasodilators, defined by a decrease in PAP of more than 20%. Synchronous right- and left-ventricular pressure measurements and four-chamber magnetic resonance (MR) imaging were used to identify timing of maximal leftward ventricular septal bowing within cardiac cycle. Septal bowing was evaluated with MR, measured on short-axis cine heart images, and expressed as curvature (reciprocal of radius). Curvature was quantified on one image (the one that showed the most severe distortion of normal septal shape). The relationship between systolic PAP and septal curvature was tested with linear regression analysis. P <.05 was considered to indicate a statistically significant difference.


RESULTS
Of 39 subjects, 37 had pulmonary hypertension. Maximal distortion of normal septal shape was found during right ventricular relaxation phase. Systolic PAP was proportional to septal curvature: r=0.77 (P < .001), slope=-114.7, and intercept=67.2. In the two vasodilator responsive subjects, a significant reduction of leftward ventricular septal bowing was observed in response to reduction of right ventricular pressure.


CONCLUSIONS
In 37 patients with pulmonary hypertension, systolic PAP higher than 67 mm Hg may be expected when leftward curvature is observed.
Roeleveld
Roald J
RJ
Departments of Pulmonology and Physics and Medical Technology, VU University Medical Center/Institute of Cardiovascular Research ICaR-VU, De Boelelaan 1117, 1081 HV Amsterdam, the Netherlands. a.vonk@vumc.nl.
Marcus
J Tim
JT
Faes
Theo J C
TJ
Gan
Tji-Joong
TJ
Boonstra
Anco
A
Postmus
Pieter E
PE
Vonk-Noordegraaf
Anton
A
D000328:Adult; D000368:Aged; D005260:Female; D006346:Heart Septum / Q000503:physiopathology*; D006352:Heart Ventricles; D006801:Humans; D006976:Hypertension, Pulmonary / Q000503:physiopathology*; D016014:Linear Models; D019028:Magnetic Resonance Imaging, Cine / Q000379:methods*; D008297:Male; D008875:Middle Aged; D011651:Pulmonary Artery / Q000503:physiopathology; D014665:Vasodilator Agents / Q000008:administration & dosage
D014665:Vasodilator Agents