The Long-Term Response to Treatment with Calcium Channel Blockers in Patients with Idiopathic Pulmonary Arterial Hypertension.

BACKGROUND

Long-term outcomes in patients with idiopathic pulmonary arterial hypertension (IPAH) treated with calcium channel blockers (CCBs) are not well documented. Therefore, this study aimed to determine the long-term response to treatment with CCBs in patients with IPAH.

METHODS

This retrospective cohort study was performed on 81 patients with IPAH admitted to our center. Vasoreactivity testing with adenosine was performed in all patients. Twenty-five patients showed a positive response to vasoreactivity testing and were included in the analysis.

RESULTS

Of 24 patients, 20 (83.3%) were female, and the mean age of the patients was 45.90±10.42 years. Fifteen patients improved after 1 year on CCB therapy (the long-term CCB responders group), and 9 showed no improvement (the CCB failure group). The CCB responders group had a greater proportion of patients in New York Heart Association (NYHA) functional class I or II (93.3%), a longer distance walked, and less severe hemodynamic parameters. At the 1-year evaluation, the long-term CCB responders had more improvements in the mean 6-minute walk test result (437.43±125.32 vs 268.17±130.06; P=0.040), the mixed venous oxygen saturation level (71.84±9.87 vs 59.03±9.95; P=0.041), and the cardiac index (4.76±1.12 vs 3.15±0.90; P=0.012). Additionally, mPAP was lower in the long-term CCB responders group (47.35±12.70 vs 67.23±14.08; P=0.034). Finally, all the CCB responders were in NYHA functional class I or II (P=0.001).

CONCLUSION

Our study illustrated that long-term treatment with oral CCBs was effective in 60% of acute responders and 18.5% of the entire study population.