Exercise during cardiac catheterization distinguishes between pulmonary and left ventricular causes of dyspnea in systemic sclerosis patients.

Objective: The cause for shortness of breath among systemic sclerosis (SSc) patients is often lacking. We sought to characterize the hemodynamics of these patients by using simple isotonic arm exercise during cardiac catheterization.

Methods: Catheterization was performed in 173 SSc patients when resting echocardiographic pulmonary systolic pressures were <40 but >40 mmHg post stress.