An integrated compliant balloon ultrasound catheter was developed to allow greater deformations in strain imaging with intravascular ultrasound. A 64-element circumferential array was placed inside a compliant silicone balloon catheter to capture real-time, phase-sensitive radio frequency (RF) data during deformation experiments. Strains over 40% could be applied to normal arterial wall tissue with intracatheter pressures as low as 200 kPa (2 atm). Strain images of a hard-soft rubber phantom, thrombus, and fibrotic plaque were produced using the integrated balloon ultrasound catheter. Results show that this catheter can apply large deformations at low pressures and image various vascular pathologies ex vivo. Potentially, it can serve as a multifunctional, intravascular therapeutic device to guide angioplasty and stent deployment.