Objective: To assess right ventricular (RV) function in patients with early systemic sclerosis (SSc) and the acute effects of calcium channel blockers on RV ejection fraction (RVEF).
Methods: Forty-two consecutive patients with SSc with less than 5 years' disease duration and normal pulmonary arterial pressure (35 women, 7 men; mean age 54.3 +/- 9.7 years; 16 with diffuse and 26 with limited cutaneous forms, systolic pulmonary arterial pressure 30.3 +/- 5.4 mmHg) were prospectively evaluated. All underwent pulmonary function testing, echocardiography, and radionuclide ventriculography at rest and 2 hours after receiving 40 mg oral nicardipine, and were compared at baseline with 20 gender and age matched controls.
Results: None of the patients with SSc had clinical evidence of heart failure. At baseline, SSc patients had significantly lower LVEF (68.5% +/- 7.9 vs 72.4% +/- 5.0, p = 0.049) and RVEF (36.5% +/- 7.0 vs 45.8% +/- 5.7, p < 0.0001). Sixteen patients had reduced RVEF (< 35%), 3 had reduced LVEF (< 55%), and 10 had reduced peak filling rate (PFR). RVEF correlated to both LVEF and PFR (r = 0.64, p < 0.0001, and r = 0.36, p = 0.0037, respectively), whereas no correlation was found with pulmonary function impairment or pulmonary arterial pressure. Nicardipine resulted in a significant increase in RVEF (from 36.5% +/- 7.0 to 42.3% +/- 8.4, p < 0.001) whereas afterload indicated by mean arterial pressure did not differ significantly.
Conclusion: Reduced RVEF appears to be a common feature in early SSc; it may be due to intrinsic myocardial involvement and is acutely improved by nicardipine.