Pulmonary hypertension in systemic sclerosis determines cardiac autonomic dysfunction assessed by heart rate turbulence

1. The prevalence of cardiac autonomic alterations was evaluated in 23 obese subjects with body mass index 37.2 ± 3.03 kg/m2 (mean ± sd), compared with 78 controls with body mass index 22.5 ± 2.6 kg/m2 (P < 0.001). 2. Cardiac autonomic function was assessed by four standard tests (heart rate response to deep breathing and to the Valsalva manoeuvre, systolic blood pressure fall after standing and diastolic pressure rise during handgrip) and by the cross-correlation test, a new method of computerized analysis of respiratory sinus arrhythmia based on spectral analysis of electrocardiographic and respiratory signals. 3. Considering tests indicative of parasympathetic function, only the heart rate response to the deep breathing and the cross-correlation test were significantly lower in the obese than in the control group [deep breathing = 13.95 ± 8.65 beats/min (mean ± sd) vs 24.5 ± 7.65, P < 0.001; cross-correlation 4.28 ± 0.74 units vs 5.14 ± 0.63, P < 0.001]. Deep breathing and/or cross-correlation were abnormal in 10 (43.5%) obese subjects (deep breathing: seven subjects, cross-correlation: eight subjects). No significant difference between groups was found for the response to the Valsalva manoeuvre: the Valsalva ratio was 1.69 ± 0.45 in obese subjects and 1.88 ± 0.33 in controls (P = NS). The Valsalva ratio was abnormal in three obese subjects. 4. No significant differences were found between groups for tests indicative of sympathetic function. The rise in diastolic blood pressure after handgrip was 12.6 ± 6.2 mmHg (1.67 ± 0.82 kPa) in obese subjects and 18.2 ± 4.9 mmHg (2.42 ± 0.65 kPa) in controls (P = NS), and the fall in systolic blood pressure after standing was −6.8 ± 8.6 mmHg (−0.90 ± 1.14 kPa) in obese subjects and −6.9 ± 10.4 mmHg (−0.91 ± 1.38 kPa) in controls (P = NS). The handgrip test was abnormal in four obese subjects, while no obese subject had an abnormal blood pressure response to standing. 5. Our findings suggest a high incidence of cardiac autonomic dysfunction in obese subjects. Since cardiac autonomic alterations have been shown to be involved in the mechanisms of cardiac sudden death, our data suggest a possible role of autonomic dysfunction in the increased risk for sudden death in obesity.

Download Full-text

Heart rate variability in systemic sclerosis. The influence of pulmonary hypertension

Atherosclerosis Supplements ◽

10.1016/s1567-5688(02)80531-1 ◽

2002 ◽

Vol 3 (2) ◽

pp. 180

Keyword(s):

Heart Rate ◽

Pulmonary Hypertension ◽

Heart Rate Variability ◽

Systemic Sclerosis

Download Full-text

EVALUATION OF CARDIAC AUTONOMIC FUNCTION WITH HOLTER ECG MONITORING IN PATIENTS WITH SYSTEMIC SCLEROSIS

Romanian Journal of Rheumatology ◽

10.37897/rjr.2015.3.5 ◽

2015 ◽

Vol 24 (3) ◽

pp. 152-159

Author(s):

Lucian Muresan ◽

◽

Ana Petcu ◽

Crina Muresan ◽

Cristina Pamfil ◽

...

Keyword(s):

Systemic Sclerosis ◽

Autonomic Dysfunction ◽

Raynaud’S Phenomenon ◽

Raynaud's Phenomenon ◽

Control Group ◽

Ecg Monitoring ◽

Premature Ventricular Contractions ◽

Holter Ecg ◽

American College Of Rheumatology ◽

Cardiac Autonomic Dysfunction

Purpose. Cardiac autonomic dysfunction is frequently encountered among patients with systemic sclerosis. Its presence correlates with potentially fatal ventricular arrhythmias, having a good positive predictive value for mortality. The aim of this paper was to identify cardiac autonomic dysfunction in patients with systemic sclerosis using Holter ECG monitoring and to assess the possible correlations between its presence and other disease characteristics. Material and methods. Forty nine patients with diffuse cutaneous and limited cutaneous scleroderma, diagnosed according to the American College of Rheumatology/EULAR 2013 criteria underwent ECG, transthoracic echocardiography, blood sample testing, chest X-ray and spirometry. Subsequently, all patients and a control group of 49 healthy subjects underwent Holter ECG monitoring with time and frequency domain heart rate variability (HRV) analysis. Results. Scleroderma patients had significantly lower HRV values compared to controls: SDNN (123 ± 39.4 vs. 143.2 ± 32, p =0.001), SDANN (137.2 ± 34.9 vs. 127.9 ± 25.7, p=0.001), TI (-) (30.6 ± 9.6 vs. 38.1 ± 8.9, p=0.01) and TINN (758.8 ± 208 vs. 815.1 ± 138, p=0.04). The LF/HF ratio was significantly higher among patients with diffuse scleroderma (1.18 ± 0.34 vs. 1.08 ± 0.43, p= 0.005). There was a positive correlation between the TI values, SDANN and the duration from the onset of Raynaud’s phenomenon (r=0.399, p=0.016) (r=0.419, p=0.011), between the SDANN values and systolic pulmonary arterial pressure (sPAP) values (0.032, p=0.034) and a negative correlation between the LF/HF values and the patients’ age (r=-0.442, p=0.001), the duration from the onset of non-Raynaud’s phenomenon (r=-0.395, p=0.034), echocardiographic value of sPAP(r=-0.330, p=0.035) and the total number of premature ventricular contractions (r=-0.0459, p=0.001). Conclusion. Patients with systemic sclerosis often have cardiac autonomic dysfunction, which can be diagnosed with Holter ECG monitoring.

Download Full-text

Chemical Sympathectomy Restores Baroreceptor-Heart Rate Reflex and Heart Rate Variability in Rats With Chronic Nitric Oxide Deficiency

Physiological Research ◽

10.33549/physiolres.932804 ◽

2015 ◽

pp. 459-466 ◽

Cited By ~ 5

Author(s):

M. CHASWAL ◽

S. DAS ◽

J. PRASAD ◽

A. KATYAL ◽

M. FAHIM

Keyword(s):

Nitric Oxide ◽

Blood Pressure ◽

Heart Rate ◽

Heart Rate Variability ◽

Frequency Domain ◽

Autonomic Dysfunction ◽

Sympathetic Innervation ◽

Chemical Sympathectomy ◽

Principal Mechanism ◽

Cardiac Autonomic Dysfunction

Nitric oxide (NO) plays a crucial role not only in regulation of blood pressure but also in maintenance of cardiac autonomic tone and its deficiency induced hypertension is accompanied by cardiac autonomic dysfunction. However, underlying mechanisms are not clearly defined. We hypothesized that sympathetic activation mediates hemodynamic and cardiac autonomic changes consequent to deficient NO synthesis. We used chemical sympathectomy by 6-hydroxydopamine to examine the influence of sympathetic innervation on baroreflex sensitivity (BRS) and heart rate variability (HRV) of chronic NG-nitro-L-arginine methyl ester (L-NAME) treated adult Wistar rats. BRS was determined from heart rate responses to changes in systolic arterial pressure achieved by intravenous administration of phenylephrine and sodium nitroprusside. Time and frequency domain measures of HRV were calculated from 5-min electrocardiogram recordings. Chronic L-NAME administration (50 mg/kg per day for 7 days orally through gavage) in control rats produced significant elevation of blood pressure, tachycardia, attenuation of BRS for bradycardia and tachycardia reflex and fall in time as well as frequency domain parameters of HRV. Sympathectomy completely abolished the pressor as well as tachycardic effect of chronic L-NAME. In addition, BRS and HRV improved after removal of sympathetic influence in chronic L-NAME treated rats. These results support the concept that an exaggerated sympathetic activity is the principal mechanism of chronic L NAME hypertension and associated autonomic dysfunction.

Download Full-text