Rate Deceleration Capacity Research Articles

Pulse rate variability predicted cardiovascular disease in sleep disordered breathing: The Guangdong sleep health study

ObjectivesPulse rate variability (PRV) predicts stroke in patients with sleep disordered breathing (SDB). However, the relationship between PRV and cardiovascular disease (CVD) was unknown in SDB. MethodsThis was a cross-sectional study. Community residents in Guangdong were investigated. Sleep study were conducted with a type Ⅳ sleep monitoring. PRV parameters was assessed from the pulse waveforms derived from the sleep monitoring. Results3747 participants were enrolled. The mean age was 53.9 ± 12.7 years. 1149 (30.7%) were diagnosed as SDB. PRV parameters, except for the averages of pulse-to-pulse intervals (ANN), were higher in participants with SDB than those without. After adjusting for traditional CVD risk factors, deceleration capacity of rate (DC), ANN, and the percentage of pulse-to-pulse interval differences that were more than 50 ms (PNN50) were correlated with CVD risk in participants with SDB (OR were 0.826, 1.002, and 1.285; P were 0.003, 0.009, and 0.010), but not in participants without SDB. There was no interaction effect between DC, ANN, PNN50 and oxygen desaturation index. In hierarchical analysis, DC and ANN were predictors for CVD in SDB patients with age <60 years, male, overweight, diabetes, and normal lipid metabolism. PNN50 was predictor for CVD in the elderly SDB patients without overweight, diabetes or dyslipidemia. ConclusionsPRV parameters may be specific predictors for CVD in SDB. PNN50 was a potent biomarker for CVD risk in the elderly with SDB, event without traditional CVD risk factors.

Turbulence and deceleration capacity of the heart rate in patients with coronary artery disease and implanted cardioverter defibrillator

Aim. To study the possibility of using of heart rate turbulence (HRT) and deceleration capacity (DC) in the risk stratification of fatal events in patients with coronary artery disease (CAD) and implanted cardioverter defibrillator (ICD). Material and methods. The study included 45 patients with sinus rhythm and verified CAD, who had indications for ICD. A 24-hour ECG monitoring was performed with the evaluation of non-invasive predictors of sudden cardiac death. The minimum observation period was 30 months (the average observation period was 48 (42;51) months). Two endpoints were assessed: the onset of deaths and the justified ICD actuations. Results. During the observation period, 10 patients died (5 from progression of heart failure, 2 from recurrent myocardial infarction, 2 from non-cardiac pathology, and 1 died suddenly before implantation of a defibrillator). Arrhythmic events occurred in 13 people. Compared to the surviving patients, deceased patients’ mean DC value was significantly lower (1,25 (0,48;2,23) ms vs 3,3 (1,85;5,40) ms, p=0,016). There were significantly more frequent DC in the high-risk zone (80% vs 34%, p=0,024) and type 2 HRT disorders (80% vs 29%, p=0,009). When comparing patients with arrhythmic events and without them, no significant differences in DC and HRT were detected. According to univariate regression analysis, HRT and DC were risk factors for death (p=0,004 and p=0,006, respectively). Conclusion. Electrophysiological markers reflecting vegetative imbalance (HRT and DC) in patients with CAD and ICD can identify patients with high risk of overall mortality, but it is not associated with the risk of ventricular tachyarrhythmias development.

Clinical value of DC and DRs in warning sudden cardiac death of patients with coronary artery disease

To make risk stratification of aged patients with coronary artery disease by deceleration capacity of rate (DC) and heart rate deceleration runs (DRs) and to investigate the value of the two detection technologies in warning sudden cardiac death. Two hundrend and eighteen patients diagnosed with coronary artery disease (CAD) by coronary angiography (CAG) were selected as observa-tion group:including 55 patients with latent coronary artery disease (LCHD), 56 patients with acute myocardial infarction (AMI), 53 patients with angina pectoris (AP), 54 patients with ischemic heart failure. Fifty-five healthy controls in our hospital were selected at the same time (control group). All patients were detected by 24-hour dynamic electrocardiogram while values of DC and DRs were automatically analyzed and calculated by software. The values of DC and DRs descended significantly in all CHD groups (AMI group, AP group, Ischemic Heart Failure group, LCHD group) and the difference was statistically significant (P < 0.01) compared with normal group; DC and DRs indicated the risk classification of each CAD subgroup was obviously higher than those in normal group and the difference was statistically significant(P < 0.01); CAG showed that the more coronary lesions, the larger the rage, prompt the heavier the illness, which was consistent with the risk classification of each CHD subgroup indicated by DC and DRs. DC and DRs can be used to analyze the function of vagus nerve, it also can be used to make risk classification of patients with CHD, and it has a higher value of pre-warning for high-risk groups. DC and DRs can be used as sensitive indexes in warning sudden cardiac death of patients with CHD.

GW26-e1333 The Relationship between Deceleration Capacity of Rate and the Severity of Coronary Artery Lesions

GW26-e1333 The Relationship between Deceleration Capacity of Rate and the Severity of Coronary Artery Lesions

T-wave alternans, heart rate turbulence and ventricular extrasystoles for the prediction of appropriate implantable cardioverter-defibrillator discharges

Purpose: Predictors for survival or Implantable Cardioverter-Defibrillators (ICD) shocks are necessary for improved patient selection and optimized therapeutic strategies. We prospectively studied the prognostic value of Premature Ventricular Contractions (PVC, normalized per 24 hours), non-sustained VT (nsVT), Heart Rate Variability (HRV), Heart Rate Turbulence (HRT) and deceleration capacity from Holter monitoring and exercise T-Wave Alternans (TWA, Cambridge heart method). Methods: Consecutive patients (pts) with sinus rhythm undergoing ICD implantation between 2008 and 2012 at our institution for approved indications were prospectively enrolled, tests were performed within four weeks after ICD implantation. Follow-Up (FU) was scheduled every 6 months (m). Deaths of any cause or appropriate (ap) ICD shocks were defined as endpoints. Data are reported as mean±SD. Risk markers for ap shocks and death were identified using Cox regression analysis. Results: A total of 282 pts [age 65±13 yrs, 75% male, NYHA 2.5±0.7, QRS 123±31 ms, Left Ventricular Ejection Fraction (LVEF) 33±13%, 36% secondary prophylaxis, 24% history of myocardial infarction, 36% dual chamber and 24% biventricular devices] were enrolled. During 24±13 m FU, 34 (12%) pts received ap shocks and 38 (14%) pts died [5 (13%) of the latter received ap shock]. When univariate predictors of [A] ap shock, [B] death and [C] combined endpoint of both were entered in a multivariate cox regression model (using dichotomization by the median for continuous variables), the following variables remained after backward elimination: [A] PVC HR 3.2 (1.23-7.99, p=0.017), HRT category HR 2.32 (0.78-6.84, p=0.129), [B] estimated glomerular filtration rate HR 2.29 (1.09-4.81, p=0.029), Low Frequency/High Frequency quotient (LF/HF) from HRV HR 2.69 (1.25-5.78, p=0.011), LVEF HR 2.90 (1.20-7.04, p=0.019) and [C] PVC HR 2.02 (1.10-3.69, p=0.023), LF/HF from HRV HR 2.01 (1.11-3.65, p=0.022) and HRT category HR 2.24 (1.04-4.84, p=0.039) Specifically, exercise TWA or nsVT did not predict all-cause mortality or ap shocks. Conclusions: The number of PVC independently predicts ap shocks in this ICD population, additionally, HRV and HRT are predictive for a combined endpoint, whereas TWA is not predictive.

Severe cardiac autonomic failure as risk predictor in patients undergoing aortic valve replacement or transcatheter aortic valve implantation

Background: A substantial number of patients with aortic valve stenosis (AS) suffer from severe cardiac autonomic failure (SAF) defined as combination of abnormal heart rate turbulence and deceleration capacity. Here we hypothesized that presence of SAF is a strong and independent predictor of adverse outcome in patients with severe AS undergoing aortic valve replacement (AVR) or transcatheter aortic valve implantation (TAVI). Methods: We included 161 consecutive patients with severe AS in sinus rhythm who underwent AVR (n=53) or TAVI (n=108) at our institution. Twenty-four hour Holter recordings were performed prior to operation. SAF was assessed according previously published technologies. SAF was considered present if Turbulence Onset ≥0%, Turbulence Slope ≤2.5ms/RRI and deceleration capacity ≤4.5ms. Multivariable analyses included SAF, age ≥80 years, increased levels of brain natriuretic peptides and the logistic Euro Score. Primary endpoint was two-year all-cause mortality. Results: During a median follow of 312 days, 11 patients died. Twenty-three of 161 patients (14.3%) were SAF-positive prior to operation. SAF-positive patients had a cumulative mortality rate of 32.6% compared to 4.2% in SAF-negative patients (p<0.0001; Figure 1). Multivariably, SAF was the only independent predictor of mortality (hazard ratio 6.1; 95% CI 1.7-21.5; p=0.006). ![Figure][1] Figure 1 Discussion: Presence of SAF is a strong and independent predictor of mortality in patients who undergo AVR or TAVI. [1]: pending:yes

Severe autonomic failure in moderate to severe aortic stenosis: prevalence and association with hemodynamics and biomarkers

Severe autonomic failure (SAF) refers to combined abnormalities in reflex and tonic autonomic function. SAF indicates increased risk of death in post-infarction and heart failure patients, but has not been studied in aortic stenosis (AS). Here, we investigated SAF in patients with AS and tested its correlation with hemodynamic and biochemical markers. We prospectively enrolled 174 patients with moderate to severe AS in sinus rhythm (age 76 ± 9 years; mean aortic valve area 0.9 ± 0.3 cm(2)). Heart rate turbulence (as marker of autonomic reflex activity) and deceleration capacity (as marker of autonomic tonic activity) were calculated from 24-h Holter recordings. According to the previously published technology, SAF was considered present if both factors were abnormal. 44 (25.3%) of the 174 patients had signs of SAF. Patients with SAF had lower left ventricular ejection fraction (LVEF: 48.1 vs. 54.8%; p = 0.002), lower mean aortic gradients (28 vs. 34 mmHg, p = 0.019), higher systolic pulmonary artery pressures (46.8 vs. 40.9 mmHg, p = 0.028), higher levels of brain natriuretic peptide (905 vs. 407 ng/l; p = 0.003) and higher levels of high sensitive troponin I (0.65 vs. 0.24 μg/l; p = 0.013). Impaired LVEF (≤50%) was the only independent factor associated with SAF, but only explained autonomic abnormalities in less than half of the patients. In patients with moderate to severe AS prevalence of SAF is high. SAF correlates with hemodynamic and biochemical markers indicating increased risk. Future studies should evaluate the prognostic value of SAF in patients with AS.

Abstract 2123: ECG Markers to Predict Cardiovascular Death: Heart Rate Variability, Deceleration Capacity and Morphologic Variability in Non-ST-Elevation ACS from the MERLIN-TIMI 36 Trial

Background : ECG parameters such as heart rate variability (HRV), deceleration capacity (DC) and morphologic variability (MV) may help identify patients at high risk post-ACS. These techniques measure specific aspects of cardiac health. HRV studies sympathovagal modulation of heart rate, DC extends heart rate turbulence by measuring acceleration-deceleration patterns, and MV quantifies variability in the shape of the ECG signal associated with myocardial instability. We assessed the relationship among HRV, DC and MV, and cardiovascular (CV) death after NSTEACS. Methods : HRV, DC and MV were calculated in 2164 placebo patients in the MERLIN-TIMI 36 trial using 24 hour Holter ECG after randomization. For each measure, patients were split into high and low risk groups (cutpoints chosen from literature: HRV LF/HF=1.2 [33.5%], DC&lt;2.5 ms [9.7%], MV LF/HF=3.7 [11.6%]). Mean clinical follow-up was 1 year. Results : Each ECG variable was associated with CV mortality when included alone in the multivariate model with the TIMI risk score (TRS) at 30 days (HR 2.8 p=0.008 for HRV, HR 4.5 p&lt;0.001 for DC and HR 5.1 p&lt;0.001 for MV) and at 1 year (HR 2.9 p&lt;0.001 for HRV, HR 2.8 p&lt;0.001 for DC and HR 2.4 p&lt;0.001 for MV). There was a stepwise increase in the risk of CV death at 1 year according to the number of abnormal ECG parameters, even after adjusting for the TRS. Conclusions : HRV, DC and MV are significantly associated with CV death both in the short and medium term following NSTEACS. Patients with multiple ECG abnormalities are at highest risk. These ECG parameters may provide complementary information to better risk-stratify patients following ACS.