Evaluation of Clinical and Genetic Modifiers of Long-term Survival in Heart Failure

Evaluation of Beta-adrenergic Receptor Gene Polymorphisms in the Long-term Effects of Beta-blockade in Patients With Chronic Heart Failure

The purpose of this study is to evaluate the beta-adrenergic receptor gene polymorphisms in the long-term effects of beta-blockade in patients with chronic heart failure.

Inclusion Criteria:

1. 18 years of age or older;
2. Patients are required to have chronic heart failure (NYHA II-IV) with a left ventricular ejection fraction lower than 40%;
3. Patients are voluntary and signed informed consent.

Exclusion Criteria:

1. Pregnant women or plan to;
2. Participate in any drug clinical trials within 3 months;
3. Serious neurological disease (Alzheimer's disease, Parkinson syndrome, progressive lower limbs or deaf patients);
4. Previous history of cancer or tumor, or pathological examination confirmed precancerous lesions;
5. Patients refused to comply with the requirements of this study to complete the research work;
6. According to the researchers, patients can not complete the study or not to comply with the requirements of this study (because of the reasons for the management or other reasons).