Right-sided heart catheterization (RHC) is the gold standard for assessment of pulmonary hemodynamics in patients with pulmonary hypertension.
Even at experienced centers,
RHCprocedures have considerable morbidity and mortality rates (1).
doppler echocardiography ist the most widely adoptednoninvasive method for hemodynamic assessment of pulmonary hypertension.
Limited acoustic window and observer dependency are the major drawbacks of doppler echocardiography.Until now there has been a paucity of MRI data demonstrating the ability of noninvasive phase-contrast MRI (PC-MRI) either with use of 2D- or 4D-techniques to assess pulmonary...
Methods and Materials
Nineteen healthy volunteers underwent high temporal resolution PC-MRI at 1,5T (Figure 1 and 2).
Velocity– and flow–time curves of PC-MRI were used to calculate absolute acceleration time (Ata),
maximum of mean velocities (MV),
volume of acceleration (AV),
and maximum flow acceleration (dQ/dt) (Figure 3 and 4).
On the basis of these parameters,
following linear combination equation was used to calculate mPAP (3): 69.446−(0.521×Ata)−(0.570×MV)+(1.507×AV)+(0.002×dQ/dt).
As a reference the tests persons were also examined by doppler echocardiography and the mPAP was calculated with the modified Bernoulli formula...
PC-MRI derived mPAP from 19 healthy test persons revealed a mean value of 18,8 +/- 3,9 mmHg.
In doppler echocardiography the mPAP mean value of the test persons was 19,4 +/- 2,1 mmHg.
Confirmatory statistical analysis demonstrated a maximum intraindividual difference of echocardiography and PC-MRI obtained mPAP values of +/- 4 mmHg.
With PC-MRI 18 out of 19 healthy test persons were identified as hemodynamically normal.
Only one person had a marginally increased mPAP value of 25,6 mmHg.
High temporal resolution PC-MRI has the capability to measure mPAP.
Patients with normal pulmonary hemodynamics can be identified by PC-MRI.
The role of PC-MRI needs to be further investigated in patients with pulmonary hypertension,
especially in comparison with RHC.
Complications of right heart catheterization procedures in patients with pulmonary hypertension in experienced centers.
J Am Coll Cardiol 2006;48:2546-52
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