Heart failure (HF) remains an important heath care problem in the United States. With the aging of the US population, this trend is expected to continue. However, patients have also benefited from advances in pharmacologic and device-based therapies such as angiotensin-converting enzyme inhibitors, β-blockers, aldosterone blockers, and implantable cardioverter-defibrillators. More recently, cardiac resynchronization therapy (CRT) has become another important therapeutic option for treating heart failure due to systolic dysfunction. In this article, we review the physiologic basis for CRT, the clinical trials that support its efficacy, and the current indications for its use. We also examine key clinical questions regarding CRT still under research, including predictors of response. Finally, we look at the future of CRT and how its indications can be expanded to benefit more patients in the future.
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