Implantable devices for heart failure monitoring and therapy.

Heart failure (HF), the cardiovascular epidemic of the twenty-first century, is associated with significant comorbidities and high mortality. The prevalence of HF is estimated around 6.5 million people and is expected to increase to 8 million by the year 2030. The associated costs to care for these patients continue to increase. Despite the advancement of pharmacologic therapy with significant improvement in morbidity and mortality, the 5-year survival for heart failure still stands at 61%. The challenges faced by HF patients include difficulty with lifestyle modifications, nonadherence to complex medical regimens, financial limitations, lack of access to medical care, and unfavorable side effects. The sickest HF patients, who are ACC/AHA stage D, have advanced therapeutic options such as left ventricular assist devices and orthotopic heart transplant; however, the majority of patients are ACC/AHA stage C and/or not candidates for such advanced care. With constraints placed on hospitals by Medicare on HF readmissions as well as the multiple comorbidities imposed by this disease, intense interest is focused on the development of implantable devices as add-on therapy. This review discusses the innovative devices under varying stages of investigation or approved for monitoring and treatment of HF.