Page 188 - Assessing right ventricular function and the pulmonary circulation in pulmonary hypertension Onno Anthonius Spruijt

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precapillary pulmonary hypertension was investigated in chapter 3. We found a good prognostic value of a simple right heart score and this score showed a good correlation with more established complex risk scores (REVEAL score and NIH score).
Treatment response in pulmonary hypertension
Since the prognosis of patients with pulmonary hypertension is determined by right ventricular function, monitoring of right ventricular function is of utmost importance. In chapter 4 we summarized available methods for measuring the right ventricular response to therapy. Cardiac magnetic resonance imaging (CMRI) is the gold standard for monitoring right ventricular function. Since CMRI scans are expensive, not widely available and analyses are time-consuming, monitoring right ventricular function using simple echocardiographic measurements would be ideal in daily practice. Therefore, in chapter 5, we investigated the usage of simple echocardiographic parameters for the serial assessment of right ventricular function by comparing four different echo-derived parameters with CMRI-derived right ventricular ejection fraction. The strongest relationship was found between CMRI-derived right ventricular ejection fraction and echo-derived right ventricular fractional area change. However, the sensitivity of echocardiography to predict a deterioration in CMRI-derived right ventricular ejection fraction was poor for all four echo-derived parameters (ranging from 33-56%). Echo-derived parameters of right ventricular systolic function, in particular right ventricular area change, can reasonably distinguish between a decreased or preserved CMRI- derived right ventricular ejection fraction. However, echo-derived parameters are not suitable for the serial assessment of right ventricular systolic function.
Patients with idiopathic pulmonary arterial hypertension and a reduced diffusion capacity of the lung for carbon monoxide (DLCO) have a worse survival compared to idiopathic pulmonary arterial hypertension patients with a preserved DLCO. Whether this poor survival can be explained by unresponsiveness to pulmonary hypertension specific vasodilatory therapy is unknown. Therefore, in chapter 6 we investigated the hemodynamic and cardiac response to PH specific vasodilatory therapy in patients with IPAH and a reduced DLCO. Baseline hemodynamics and cardiac function were not different in the two groups and hemodynamics and cardiac function improved in both groups after PH specific vasodilatory therapy without a worsening of oxygenation at rest or during exercise. Therefore, we concluded that patients with idiopathic pulmonary arterial hypertension and a severely reduced DLCO show a similar response to pulmonary hypertension - specific vasodilatory