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PubMed1991

The influence of autonomic neuropathy on mortality in insulin-dependent diabetes.

Five-year survival was investigated in 506 randomly selected patients with insulin-dependent diabetes mellitus screened for autonomic neuropathy with a series of cardiac autonomic function tests. Of the 484 diabetics traced, 44 (9 per cent) had died. The cumulative 5-year mortality rate was increased more than five-fold in those with autonomic neuropathy: 27 per cent vs. 5 per cent in those with normal autonomic function. Discriminant analysis of survivors and non-survivors showed that autonomic neuropathy was the most important independent predictor of death. Among those who died, autonomic neuropathy was associated with an increased frequency of retinopathy and peripheral neuropathy and a slightly lower frequency of macrovascular disease. Autonomic neuropathy was associated with an increased mortality rate from renal failure, but not from any other causes.

Adolescent↗
PubMed1998

Fractal dimension and approximate entropy of heart period and heart rate: awake versus sleep differences and methodological issues.

1. Investigations that assess cardiac autonomic function include non-linear techniques such as fractal dimension and approximate entropy in addition to the common time and frequency domain measures of both heart period and heart rate. This article evaluates the differences in using heart rate versus heart period to estimate fractal dimensions and approximate entropies of these time series.2. Twenty-four-hour ECG was recorded in 23 normal subjects using Holter records. Time series of heart rate and heart period were analysed using fractal dimensions, approximate entropies and spectral analysis for the quantification of absolute and relative heart period variability in bands of ultra low (<0.0033 Hz), very low (0. 0033-0.04 Hz), low (0.04-0.15 Hz) and high (0.15-0.5 Hz) frequency.3. Linear detrending of the time series did not significantly change the fractal dimension or approximate entropy values. We found significant differences in the analyses using heart rate versus heart period between waking up and sleep conditions for fractal dimensions, approximate entropies and absolute spectral powers, especially for the power in the band of 0.0033-0.5 Hz. Log transformation of the data revealed identical fractal dimension values for both heart rate and heart period. Mean heart period correlated significantly better with fractal dimensions and approximate entropies of heart period than did corresponding heart rate measures.4. Studies using heart period measures should take the effect of mean heart period into account even for the analyses of fractal dimension and approximate entropy. As the sleep-awake differences in fractal dimensions and approximate entropies are different between heart rate and heart period, the results should be interpreted accordingly.

Adult↗
PubMed1998

Impaired heart rate variability in patients with symptomatic NYHA class II-III hypertrophic cardiomyopathy.

Power spectral analysis of heart rate variability was performed to assess cardiac autonomic function using Holter monitoring in 19 hospitalized patients with symptomatic NYHA class II-III hypertrophic cardiomyopathy (sHCM), 20 ambulatory patients with asymptomatic NYHA class I hypertrophic cardiomyopathy (asHCM) and 20 normal control subjects. Power spectral analysis decomposed the heart rate variability into high-frequency power (HF: 0.15-0.40 Hz) and low-frequency power (LF: 0.04-0.15 Hz). HF was corrected by mean RR intervals (CCVHF). CCVHF values and LF/HF ratios were used as indices of vagal and sympathetic modulations, respectively. The sHCM group demonstrated no significant elevation in CCVHF during the nighttime as compared to the daytime, while asHCM and control groups showed significant CCVHF elevation during the nighttime (p < 0.05-0.01). The nighttime CCVHF, therefore, was significantly lower in the sHCM group than in the control or asHCM group (sHCM, 1.08 +/- 0.36%; control, 1.60 +/- 0.57%; asHCM 1.82 +/- 0.77%; sHCM vs. control or sHCM vs. asHCM, p < 0.01). All of these three groups showed significant reduction in LF/HF ratio during the nighttime as compared to the daytime (p < 0.01). However, the reduction in the sHCM group was not as great as that in the control group and there was a significant difference between the sHCM and control group (2.01 +/- 1.58 vs. 1.08 +/- 0.65, p < 0.05). Two patients in the sHCM group, who later died suddenly, demonstrated very low CCVHF throughout a 24-hour period (0.2-0.8%). Both vagal and sympathetic impairment with a predominance of vagal abnormalities is suggested in patients with symptomatic NYHA class II or III hypertrophic cardiomyopathy.

Adult↗
PubMed2000

Autonomic regulation of cardiac function during sleep in patients with irritable bowel syndrome.

OBJECTIVE: Several studies have provided evidence of abnormal autonomic activity in irritable bowel syndrome (IBS), suggesting that abnormal central nervous system-autonomic nervous system arousal mechanisms may be part of its pathophysiology. The goal was to investigate cardiac sympatho-vagal balance during waking and the different stages of sleep using heart rate variability analysis in IBS patients compared to healthy controls. METHODS: A total of 15 IBS patients (13 female, two male, mean age 34.9 +/- 2.1 yr) and 15 controls (13 female, two male, mean age 36.2 +/- 2.3 yr) were studied during 1 h of pre-sleep quiet waking and during seven-hours of sleep. Polysomnography was used for the determination of state of consciousness. Electrocardiography provided the beat-to-beat intervals, which were then subjected to spectral analysis for determination of the percentage of energy in the low and high frequency bands, respectively. The low frequency/high frequency band ratio was also calculated. For each subject, heart rate variability analysis was performed using 15-min segments of waking, non-rapid eye movement sleep, and rapid eye movement sleep. RESULTS: The low frequency band power was significantly greater in IBS patients during waking. No group differences were found in high frequency band power during any state. The low frequency to high frequency band ratio was significantly greater in IBS patients during rapid eye movement sleep. CONCLUSIONS: IBS patients have greater sympathetic activity during waking and greater overall sympathetic dominance during rapid eye movement sleep. These results support the presence of autonomic abnormalities in patients with IBS. The possibility is discussed that sympathetic dominance during rapid eye movement sleep may play a role in sensitizing the gut to waking stimulation.

Adult↗
PubMed2000

Plasma big-endothelin levels, cardiac autonomic neuropathy, and cardiac functions in patients with insulin-dependent diabetes mellitus.

BACKGROUND: The alteration of endothelin (ET) levels in diabetic patients with cardiac autonomic neuropathy (CAN) has not been studied extensively and its correlation with cardiac function parameters has not been discussed. HYPOTHESIS: The aim of the present study was to discuss the correlation between the degree of cardiac autonomic neuropathy, plasma big-ET levels, and cardiac functions in diabetic patients who were clinically free of cardiovascular disease. METHODS: Twenty subjects (32.1 +/- 7.8 years, 11 men, 9 women) with insulin-dependent diabetes mellitus (IDDM) were studied to evaluate the relationship between circulating big-endothelin (big-ET1) levels, CAN, and cardiac functions. The severity of CAN was scored according to Ewing's criteria. Cardiac functions were assessed using Doppler echocardiography. RESULTS: Left ventricular systolic function in the patient group was within normal limits and comparable with the values of the control group (n = 10). The mean E/A values of diabetics with CAN (1.15 +/- 0.33, p = 0.004) and without CAN (1.34 +/- 0.17) were significantly lower than those of controls (1.57 +/- 0.27). Diabetics with CAN had significantly higher big-ET1 values (81.1 +/- 94 pg/ml) compared with others (12.4 +/- 5.9 and 21.1 +/- 17.7 pg/ml, p = 0.04). Circulating big-ET1 levels showed a significant correlation with E/A values in the control group (p = 0.01, r = -0.7) and with peak A values (p = 0.003, r = 0.64) in diabetics. The CAN score correlated negatively with E/A values (p = 0.01, r = 0.54). CONCLUSIONS: High big-ET levels might have an important role in the pathogenesis or consequences of diastolic dysfunction in diabetics with CAN. Their role in cardiac autonomic neuropathy and diastolic dysfunction should be investigated further.

Adult↗
PubMed2004

A functional-structural model to understand cardiac autonomic nervous system (ANS) dysregulation in affective illness and to elucidate the ANS effects of antidepressive treatment.

Numerous studies provide evidence that major depression (MD) is associated with certain disorders of cardiac autonomic nervous system (ANS) function, in particular, with an autonomic neurocardiac imbalance characterized by a low cardiovagal modulation, a raised sympathetic nerve activity and a high resting heart rate. We assume that such MD-associated cardiac ANS disorders are mainly caused by functional-structural abnormalities within the central autonomic network (CAN), in particular, by well-defined abnormalities of hypothalamic structures in MD. In view of the well-known association between an autonomic neurocardiac imbalance and the risk for cardiac arrhythmias, we assume that MD-associated cardiac ANS disorders are at least partly responsible for the high cardiovascular mortality risk in MD. It is, however, still unclear whether antidepressive treatment will lower the risk for cardiovascular complications in MD. There is convincing evidence that a successful antidepressive treatment with electroconvulsive therapy, cognitive behavioral therapy, or pharmacotherapy with primarily non-antimuscarinergic antidepressants can improve an initially disturbed cardiac ANS function in MD. These studies correspond well to our findings that treatment with both, nefazodone or reboxetine, can induce a reduction of central sympathetic nerve activity and an increase of the initially lowered cardiovagal modulation depending on the improvement of depressive symptoms after treatment. Since both effects occured obviously independent from the primarily serotonergic or noradrenergic action of the antidepressants, our findings suggest the existence of a generally supraordinate and uniform mechanism underlying the ANS effects of antidepressive treatment with drugs inhibiting serotonin- or noradrenaline reuptake.

Antidepressive Agents↗
PubMed1987

Effects of autonomic blockade on cardiac function at rest and during upright exercise in humans.

The cardiac function was studied by radionuclide cardiography in eight healthy subjects at rest and during submaximal upright exercise before and after autonomic blockade with metoprolol and atropine. At rest the median stroke volume was reduced by 21% during autonomic blockade (P less than 0.01), but cardiac output was maintained by a concomitant increase in heart rate. The systolic blood pressure was reduced from 120 to 105 mmHg (P less than 0.01), and left ventricular ejection fraction was reduced from 61 to 56% (P less than 0.05). After autonomic blockade the heart rate reached during exercise was the same. Stroke volume and cardiac output were maintained through cardiac dilation. The increase in left ventricular end-diastolic volume was 31 vs. 10% during control conditions (P less than 0.01). The systolic blood pressure was reduced from 174 to 135 mmHg (P less than 0.01). Left ventricular ejection fraction was reduced from 75 to 67% (P less than 0.05), but the increase from rest to exercise was preserved. Total peripheral resistance was reduced by 17% (P less than 0.05). These findings suggest that the heart possesses intrinsic mechanisms to maintain cardiac output during submaximal upright exercise. End-diastolic dilation results in a preserved stroke volume despite a reduced contractility.

Adult↗
PubMed1999

Myocardial 123I-MIBG kinetics in acutely hypothyroid patients with differentiated thyroid carcinoma.

Marked changes in cardiac function have been noted in patients with hyperthyroidism or hypothyroidism due both to changes in sympathetic system function and to biochemical modifications of myocardial tissue. Metaiodobenzylguanidine (MIBG), an analogue of norepinephrine, can be used to evaluate myocardial sympathetic tone. Here, we report myocardial 123I-MIBG kinetics in patients with differentiated thyroid carcinoma undergoing acute hypothyroidism followed by hormonal replacement as part of their routine clinical follow-up. Ten patients with differentiated thyroid carcinoma in acute hypothyroidism (A) and on hormonal replacement with thyroxine (150 micrograms.day-1) and triiodothyronine (20 micrograms.day-1) (B) underwent scintigraphic imaging 20 min and 4 h after injection of 111 MBq of ultra-high specific activity 123I-MIBG. No patient had cardiac disease or was taking medications that could interfere with cardiac or autonomic system function. Cardiac MIBG kinetics (heart-to-mediastinum, H/M, ratio and myocardial washout rate), serum norepinephrine, T3, T4, FT3, FT4, TSH, CPK, CPK-MB, blood pressure and ECG were evaluated. Systolic and diastolic blood pressure did not differ significantly between state A and state B. In the acute hypothyroid state (A), the prevalence of non-specific ST-T abnormalities was 70% and heart rate was significantly different (P < 0.001) than in state B. Norepinephrine and CPK-MB levels were higher during hypothyroidism, but this did not reach statistical significance. A positive correlation between early H/M and delayed H/M in the hypothyroid state (r = 0.57) and an even higher positive correlation between early H/M and delayed H/M in the euthyroid state (r = 0.91) were seen. The myocardial and mediastinal MIBG washout rates were significantly different between the hypothyroid and euthyroid states (P < 0.05), whereas the lung washout rate did not differ significantly between the two metabolic states. We conclude that the myocardial washout rate during hypothyroidism is clearly increased (P < 0.005) with a subclinical derangement of myocardial adrenergic innervation, which is rapidly reversed with hormonal therapy.

3-Iodobenzylguanidine↗
PubMed2003

[Autonomic control of cardiac function involves modulation of hyperpolarization activated channels in vitro].

We examined the role of hyperpolarization-activated currents (Ih) in heart rate regulation in mongrel white rats. The ZD 7288 blocking agent decreased the heart rate. Vagus stimulation in bradycardia also decreased the heart rate and was dose-depended. Vagotomy following the ZD 7288 administration induced different dose-dependent changes in heart activity. The index figures of the heart activity following beta-AR isoproterenol administration depended on the level of hyperpolarization-activated currents. The data suggest existence of a possible modulating effect of the ANS on the hyperpolarization-activated activity of the channels.

Animals↗
PubMed1994

Altered autonomic regulation of cardiac function during head-up tilt after 28-day head-down bed-rest with counter-measures.

The effects of 28 days continuous 6 degrees head-down tilt bed-rest on heart rate variability and the slope of the spontaneous arterial baroreflex were evaluated during supine rest and the first 10 min of 60 degrees head-up tilt. Twelve healthy men were assigned to either a no counter-measure (No-CM), or a counter-measure (CM) group so that there was no difference in maximal oxygen uptake. Counter-measures consisted of short-term, high resistance exercise for 6 days per week from days 7-28, and lower body negative pressure (-28 mmHg) for 15 min on days 16, 18, 20 and 22-28. In spite of balanced between-group fitness, mean RR-interval was different between the No-CM and the CM group prior to bed-rest, but neither this nor any other variables showed significant counter-measure by bed-rest interaction effects. Therefore, all data presented are from the main effects of bed-rest or tilt from the analysis of variance. RR-interval was reduced significantly by bed-rest and by tilt (P < 0.0001). Indicators from spectral analysis of heart-rate variability suggested reduced parasympathetic nervous system activity with bed-rest (P < 0.01) and head-up tilt (P < 0.05), and increased sympathetic nervous system activity after bed-rest (P < 0.01). An indicator of complexity of cardiovascular control mechanisms, taken from the slope (beta) of log spectral power vs. log frequency relationship, suggested reduced complexity with bed-rest (P < 0.05) and head-up tilt (P < 0.01). The spontaneous baroreflex slope was reduced significantly by bed-rest (P < 0.03) and by head-up tilt (P < 0.04). Taken together, these data support the concept of altered autonomic nervous system function in the aetiology of cardiovascular deconditioning with bed-rest or space travel; and it would appear that no benefit is derived from these specific counter-measures.

Adult↗
PubMed1996

Demonstration of regional sympathetic denervation of the heart in diabetes. Comparison between patients with NIDDM and IDDM.

OBJECTIVE: Global myocardial uptake of 123I-metaiodobenzylguanidine (MIBG) has been shown to be decreased in diabetic patients with autonomic neuropathy, indicating cardiac sympathetic dysfunction. However, possible differences in myocardial MIBG distribution between NIDDM and IDDM diabetic patients are not known. RESEARCH DESIGN AND METHODS: Regional myocardial distribution of 123I-MIBG was studied in seven male IDDM patients (age 45 +/- 2 years, duration of diabetes 30 +/- 3 years, means +/- SE) and 13 NIDDM patients (8 men, 5 women, age 59 +/- 2 years, duration of diabetes 10 +/- 1 years). A dual-tracer single-photon emission tomography was carried out with 123I-MIBG and 99mTc-methoxyisobutylisonitrrile to asses simultaneously myocardial sympathetic innervation and perfusion at rest. Conventional autonomic nervous function tests, power spectral analysis of heart rate variability, and echocardiography were performed for assessments of autonomic function and cardiac dimensions and function. RESULTS: Autonomic nervous function tests and echocardiography showed similar results in IDDM and NIDDM patients. Despite this, global myocardial MIBG uptake (0.43 +/- 0.04 vs. 0.59 +/- 0.06, P = 0.03) and MIBG heart-to-liver ratio (0.59 +/- 0.03 vs. 0.68 = 0.03, P = 0.05) were lower in NIDDM compared with IDDM patients. Regional distribution of MIBG uptake and regional MIBG/perfusion ratio revealed significantly reduced uptake in NIDDM patients especially in the inferoposterior segments of the left ventricle compared with IDDM patients. Difference in age between NIDDM and IDDM patients did not explain the results. CONCLUSIONS: Reduced myocardial MIBG uptake was found in NIDDM patients compared with the uptake in IDDM patients, particularly involving inferoposterior segments. Regional sympathetic damage not detectable with conventional autonomic function tests is relatively common in NIDDM.

3-Iodobenzylguanidine↗
PubMed2006

Hypoxemia and autonomic nervous dysfunction in patients with chronic obstructive pulmonary disease.

OBJECTIVE: Hypoxemia is known to be associated with abnormal heart rate variability (HRV) that can reflect the severity of the illness and may have prognostic value in patients with chronic obstructive pulmonary disease (COPD). The aim of this study was to examine the relationship between the derangements in cardiac autonomic nervous function and the oxygenation status or degree of airflow obstruction in COPD patients by using HRV analysis. METHODS: Thirty clinically stable COPD patients and 18 age-matched normal subjects were included in this study. The normalized high-frequency power (nHFP) and the low-/high-frequency power ratio (LFP/HFP) were used as indices of vagal activity and sympathovagal balance, respectively. RESULTS: Although global HRV measures were all significantly decreased, the nHFP and LFP/HFP of COPD patients were not significantly different from those of normal controls. There was a negative correlation between nHFP and arterial partial pressure of O2 (PaO2) and a positive correlation between LFP/HFP and PaO2 in COPD patients. No correlation existed between forced expiratory volume in 1.0 s/forced vital capacity (FEV1/FVC), % predicted of FEV1 (%FEV1) and nHFP or LFP/HFP in COPD patients. CONCLUSIONS: The resting autonomic nervous function of COPD patients is not different from that of normal controls. Though the degree of airway narrowing is not related to the cardiac autonomic nervous function, chronic hypoxemia can lead to enhanced cardiac vagal activity and depressed sympathetic activity in COPD patients. A worse oxygenation status is associated with increased cardiac vagal and decreased cardiac sympathetic activities in COPD patients.

Aged↗
PubMed2001

Cardiovascular haemodynamics and cardiac autonomic control in patients with subclinical and overt hyperthyroidism.

OBJECTIVE: To characterize cardiac structure and function and cardiac autonomic control in patients with subclinical and overt hyperthyroidism. DESIGN: Thirty patients with subclinical hyperthyroidism and 30 with overt disease were selected from patients never previously treated for endocrinological disease in the outpatient clinic of our institution. Twenty normal individuals were studied as control group. METHODS: Left ventricular structure and function and cardiac autonomic control were evaluated, respectively, by two-dimensional Doppler echocardiography and by 24-h Holter recording with heart rate variability analysis. RESULTS: Patients with overt hyperthyroidism showed greater values of left ventricular end-diastolic volume (P<0.05) and left ventricular mass (P<0.05) than patients with subclinical disease. In addition, the mean velocity of left ventricular fibre shortening (P<0.05) and left ventricular ejection fraction (P<0.05) were greater in patients with overt hyperthyroidism than in patients with subclinical disease. No difference in any of these parameters was detectable between normal subjects and patients with subclinical disease. The isovolumic relaxation period was shorter in patients with subclinical hyperthyroidism than in control individuals (P<0.05) and in patients with overt hyperthyroidism (P<0.05). As regards cardiac autonomic control, all time and frequency domain measures decreased progressively from control individuals to patients with subclinical hyperthyroidism and those with overt disease (P<0.001). CONCLUSIONS: Thyrotoxic patients show changes in left ventricular structure and increased echocardiographic indexes of myocardial contractility, whereas the only echocardiographic feature detectable in patients with subclinical hyperthyroidism is an increased velocity of left ventricular relaxation. Cardiac parasympathetic withdrawal is evident in patients with overt hyperthyroidism and in patients with subclinical disease.

Adult↗
PubMed1986

Abnormal cardiac function in diabetic patients with autonomic neuropathy in the absence of ischemic heart disease.

To determine if cardiac autonomic neuropathy (CAN) contributes to diabetic cardiomyopathy, left ventricular function was assessed by resting and exercise radionuclide ventriculography (RVG) in 30 patients with long-standing insulin-dependent diabetes mellitus who had no clinical, electrocardiographic, or tomographic thallium scan evidence of heart disease. In 11 of 30 patients (37%), RVG revealed abnormal left ventricular performance. CAN was found in 91% of these patients. RVG was abnormal in 59% of patients with CAN and in only 8% of patients without CAN (P less than 0.005). There were significant reductions in mean (+/- SE) ejection fractions (EF) in patients with CAN at rest (62.8 +/- 2.2% vs. 75.2 +/- 2.5%; P less than 0.001) and with maximal exercise (65.8 +/- 2.6% vs. 80.9 +/- 2.3%; P less than 0.001) compared to patients without CAN. There was an inverse correlation between the autonomic function score and both resting EF (r = -0.53; P less than 0.002) and exercise EF (r = -0.55; P less than 0.002). Systolic function did not correlate with age, sex, duration or control of diabetes, microvascular complications, or plasma norepinephrine levels. Thus, approximately one third of our study population had evidence for depressed left ventricular function in the absence of ischemic heart disease, and the cardiac dysfunction was related to the severity of CAN. CAN may be a contributor to cardiac dysfunction in diabetes mellitus.

Adult↗
PubMed2005

Autoantibodies to autonomic nerves associated with cardiac and peripheral autonomic neuropathy.

OBJECTIVE: This study examines whether autonomic nerve autoantibodies (ANabs) are associated with development of autonomic neuropathy using a prospective study design. RESEARCH DESIGN AND METHODS: A group of type 1 diabetic patients were followed prospectively with regard to autonomic nerve function on four occasions. At the third examination, 41 patients were tested for ANabs (complement-fixing autoantibodies to the sympathetic ganglion, vagus nerve, and adrenal medulla), and the results were related to cardiac autonomic nerve function (heart rate variation during deep breathing [expiration/inspiration ratio] and heart-rate reaction to tilt [acceleration and brake index]) and to peripheral sympathetic nerve function (vasoconstriction after indirect cooling [vasoconstriction index]). RESULTS: ANabs were detected in 23 of 41 (56%) patients at the third examination. Compared with patients without ANabs (ANabs-), patients with ANabs (ANabs+) showed significantly higher frequencies of at least one abnormal cardiac autonomic nerve function test at the third examination (17 of 23 [74%] vs. 7 of 18 [39%]; P = 0.03) and fourth examination (15 of 21 [71%] vs. 4 of 16 [25%]; P < 0.01). In contrast, there was no similar difference at the first or second examination. The relative risk for ANabs(+) patients to develop cardiac autonomic neuropathy at follow-up was 7.5 (95% CI 1.72-32.80). The vasoconstriction index was more abnormal in ANabs+ than in ANabs- patients at the fourth examination (median 1.40 [interquartile range 1.58] vs. 0.35 [2.05]; P = 0.01). CONCLUSIONS: ANabs were associated with future development of cardiac and peripheral autonomic neuropathy in diabetic patients, implying an etiological relationship between nervous tissue autoimmunity and these diabetes complications.

Adolescent↗
PubMed2004

Abnormalities of neurohormonal and cardiac autonomic nervous activities relate poorly to functional status in fontan patients.

BACKGROUND: Impaired cardiac autonomic nervous activities and increased neurohumoral activities (CANA, NHA) characterize Fontan patients. However, the clinical significance of these changes is not clearly understood. Our purpose was to clarify the clinical significance of the CANA and NHA in stable Fontan patients. METHODS AND RESULTS: We divided 22 atriopulmonary connection (APC) and 75 total cavopulmonary connection (TCPC) patients into 4 subgroups according to New York Heart Association (NYHA) class (1.8+/-0.6) and measured various CANA and NHA indices. All NHA indices were elevated in the symptomatic patients (P<0.001). Natriuretic peptides were higher in the APC than in the TCPC patients, and the hemodynamics showed no correlation with brain natriuretic peptide in the APC patients. Low arterial oxygen saturation and impaired hemodynamics greatly influenced all elevated NHA indices (P<0.01), except for plasma renin activity, in the TCPC patients. Impaired CANA indices did not relate to NYHA class, although surgeries were associated with lower heart rate variability. In addition to poor correlation between NHA and CANA, age and ventricular morphology had no impact on all CANA and NHA indices, except for high norepinephrine in right ventricular Fontan patients. CONCLUSIONS: Although symptomatic Fontan patients exhibit higher NHA, CANA is not related to either NYHA class or NHA. APC itself is responsible for higher natriuretic peptides, and arterial oxygen desaturation has a great impact on elevated NHA in the TCPC patients. These characteristics of the NHA and CANA differ from those of heart failure patients with biventricular physiology.

Adolescent↗