Paradoxical improvement in exercise tolerance and peak VO2 consumption after treatment with ivabradine and beta-blockers in a patient with mild dilated cardiomyopathy and inappropriate sinus tachycardia—a case report

This case highlights a paradoxical improvement in exercise tolerance and peak VO2 with combined ivabradine and beta-blocker therapy in a patient with IST. The treatment optimized the HR response during exercise, suggesting that individualized strategies can enhance exercise performance in patients with IST and mild cardiomyopathy, despite the expected limitations of these medications.