| Prognostic Heart Failure Trials | Data Sample Set | Results |
|---|---|---|
| Prospective study of heart rate variability and mortality in chronic heart failure: results of the United Kingdom heart failure evaluation and assessment of risk trial (UK-heart) [47] | 482+/-161 days follow-up. 433 patients, 54 deaths. 24 hour Holter records . |
Reduced SDNN is an independent predictor besides cardiothoracic ratio, left ventricular end-systolic diameter, and serum sodium. |
| Depressed low frequency power of heart rate variability as an independent predictor of sudden death in chronic heart failure [48] | 22+/-18 month follow-up. 190 patients, 55 deaths. 24 hour / 10-19h daytime Holter records. |
Reduced SDNN is an independent predictor besides coronary artery disease and cardiothoracic ratio. Reduced LF during daytime is an independent predictor besides coronary artery disease in a sudden death subgroup. |
| Short-term heart rate variability strongly predicts sudden cardiac death in chronic heart failure patients [49] | Three years follow up. 202 patients (total mortality: 37%, sudden death mortality: 9.4%) in derivation sample. 242 patients (total mortality: 22%, sudden death mortality: 8%) in the validation sample. 5 min data sets during controlled breathing. |
In the derivation sample reduced LF was an independent sudden death predictor besides left ventricular end-diastolic diameter. In the validation sample reduced LF was an independent sudden death predictor besides ventricular premature contractions. |
| Different spectral components of 24 h heart rate variability are related to different modes of death in chronic heart failure [50] | Three years follow up. 330 patients, mortality due to pump failure / urgent transplantation: 24%, due to sudden death: 9%. 24 hour, night-time 0-5h, daytime 9-19h Holter records. |
Reduced VLF (night-time), high pulmonary wedge pressure and low left ventricular ejection fraction independently predic death for progressive pump failure / urgent transplantation. Reduced LF (night-time) and increased left ventricular end-systolic diameter independently predict sudden death. |
| Nonlinear indices of heart rate variability in chronic heart failure patients: redundancy and comparative clinical value [44] | 31 (4-36) months follow up. 200 patients, cardiac death n=60, heart transplantation n=37, non-cardiac death n=2, drop out n=2. 24 hour Holter records. |
Only 1VP (symbolic pattern) and IMAI2 (LF-HF related empirical mode decomposition) added independent prognostic value to major clinical and functional predictors: symptom severity, left ventricular ejection fraction, peak VO2 at cardiopulmonary exercise testing and systolic arterial pressure, however other candidates such as sample entropy, DFA, and alpha slope did not. |
| Autonomic response to cardiac dysfunction in chronic heart failure - a risk predictor based on autonomic information flow [45] | 31 (4-36) months follow up. 200 patients, 100 cardiac death or heart transplantation. 24 hour Holter records. |
BDNN and PDmVLF added independent prognostic value to NYHA class, LVEF, SAP, peak_VO2 (see example below). |
| Prognostic Post Myocardial Infarction Trails | ||
| Baroreflex sensitivity and heart-rate variability in prediction of total cardiac mortality after myocardial infarction. ATRAMI (Autonomic Tone and Reflexes After Myocardial Infarction) Investigators [33] | 21 (8) months follow up 1284 patients, 44 cardiac deaths and 5 non-fatal cardiac arrests 24 hour Holter records |
Low values of either BRS or SDNN are independent predictors besides left ventricular ejection fraction and the rate of ventricular premature contractions. The association of low BRS and SDNN further increases risk. |
| Fractal analysis of heart rate dynamics as a predictor of mortality in patients with depressed left ventricular function after acute myocardial infarction. TRACE Investigators (TRAndolapril Cardiac Evaluation) [43] | 4-years follow-up 159 patients with depressed left ventricular ejection fraction after myocardial infarction, 72 patients died. 24 hour Holter records |
DFA based scaling exponent (<11 beats) was independent predictor in a multivariable Cox proportional regression model besides age, history of angina pectoris, diuretic medication, and left ventricular ejection fraction. None of the linear HRV indices had prognostic value. |
| Mortality in patients with unstable angina | ||
| Prognostic value of ventricular arrhythmias and heart rate variability in patients with unstable angina [51] | 6 months follow up 543 patients, 40 death 24 hour Holter records |
Ventricular arrhythmias add independent predictive value to clinical and laboratory variables. SDNNindex, LF, LF/HF are predictive in univariate analysis. But LF only adds independent predictive value in multivariate Cox survival analysis. |