Effects of Pilates Breathing Versus Diaphragmatic Breathing on Oxygen Saturation and Heart-Rate Variability in Post-Percutaneous Coronary Intervention Patients

Percutaneous Coronary Intervention (PCI) is a common procedure used to restore coronary blood flow in patients with coronary artery disease. Post-PCI patients may experience reduced exercise tolerance, altered breathing patterns, and autonomic imbalance, which may affect oxygen saturation and heart-rate variability (HRV). Breathing exercises are simple, non-pharmacological interventions that may support early recovery. This randomized controlled trial aims to compare the effects of Pilates breathing and diaphragmatic breathing on oxygen saturation and HRV in hemodynamically stable post-PCI patients. A total of 36 participants will be randomly allocated into two groups using a sealed opaque envelope method. The Pilates breathing group and diaphragmatic breathing group will receive supervised breathing exercises for 2 consecutive days, with three sessions per day, in addition to routine care. Oxygen saturation will be assessed using a pulse oximeter, while HRV will be measured using a Polar H10 chest belt. Pre- and post-intervention measurements will be compared between the two groups.