Assessment of heart rate recovery after exercise in patients with systemic sclerosis

systemic sclerosis is chronic,autoimmune disease characterized by excessive accumulation of collagen and other connective tissue macromolecules in the skin and internal organs as a result of fibroproliferative, microvascular and immunological changes. Clinical presentation with skin involvement although severe internal organ involvement the damage started at an early stage. clinical manifestation after organ dysfunctions in the clinic was delayed in treatment and decreased in survival. Cardiac involvement occurs with direct or indirect effects. Cardiac involvement is one of the most important causes of mortality in SSC. Routine examinations, ECG, transthoracic echocardiography are recommended for the detection of asymptomatic involvement, even in the absence of complaints during periodic controls of patients. But the disease is difficult to detect with these tests at early stages. Heart rate recovery (HRR) is a simple measure for determining cardiac autonomic activity in healthy and cardiovascular patients. In our study, there was a notable decrease in HRR in patients compared to control subjects and the sudden decrease between HRR1 and HRR5 was statistically significant. The significant sudden decrease between HRR1 and HRR5 shows that there is a dysfunction in not only in vagus but also in sympathetic system. Considering, the sympathetic system is more effective between HRR1 and HRR5, there should be more studies about dysfunction of sympathetic system in systemic sclerosis.