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To investigate the effects of obesity and weight loss on cardiovascular autonomic function, we examined 28 obese patients referred for weight-reducing gastroplasty, 24 obese patients who received dietary recommendations, and 28 lean subjects. Body weight, blood pressure, and 24-hour urinary norepinephrine excretion were measured, and time and frequency domain indexes of heart rate variability (HRV) were obtained from 24-hour Holter recordings. A measure of long-term HRV, the SD of all normal RR intervals (SDANN), was used as an index of sympathetic activity and the high-frequency (HF) component of the frequency domain, reflecting short-term HRV, as an estimate of vagal activity. All 3 study groups were investigated at baseline, and the 2 obese groups were reexamined at 1-year follow-up. Obese patients had higher blood pressure, higher urinary norepinephrine excretion, and attenuated SDANN and HF values than lean subjects (p <0.01). Obese patients treated with surgery had a mean weight loss of 32 kg (28%), whereas the obese group treated with dietary recommendations remained weight stable (p <0.001). At follow-up the weight-loss group displayed decreases in blood pressure and norepinephrine excretion and showed increments in SDANN and HF values. These changes were significantly greater than those observed in the obese control group (p <0.05). Our findings suggest that obese patients have increased sympathetic activity and a withdrawal of vagal activity and that these autonomic disturbances improve after weight loss. [ABSTRACT FROM AUTHOR]

Tigaran S, Mølgaard H, Dam M. Atrio-ventricular block: a possible explanation of sudden unexpected death in epilepsy. Acta Neurol Scand 2002: 106: 229–233. © Blackwell Munksgaard 2002 Introduction – This is the third case report describing the occurrence of total atrio-ventricular (AV)-block as a life threatening cardiac arrhythmia complicating epileptic seizures. Case report – A 56-year-old right-handed man was admitted to our hospital for surgical assessment of his medically intractable epilepsy. During the hospitalization he was enrolled in a study investigating cardiac complication of epileptic seizures as the possible cause of sudden unexplained death among epileptics. Discussion – To the best of our knowledge, we are the first to employ simultaneous video-electroencephalogram-, Holter- and pulse oximetry-recordings of our patients in the description of this complication. These recordings allowed us to discuss the evidence and consequences of this particular cardiac abnormality as an explanation of sudden unexplained death in epileptic seizures, especially those of temporal origin. [ABSTRACT FROM AUTHOR]

Do distraction from- or attention to sural nerve stimulation affect pain, heart rate variability, and a spinal withdrawal reflex? In 26 male volunteers, electrical stimulation at the distal cutaneous receptive field of the sural nerve elicited pain and a nociceptive withdrawal reflex. Intensity of pain was rated on a numeric rating scale. Electromyographic reflex responses were measured from biceps femoris muscle. Cardiac autonomic function was estimated by heart rate variability measures and was expressed in the time domain as mean of RR-intervals for normal heart beats (mean-RR) and standard deviation of all normal RR-intervals (SD-NN) and, in the frequency domain, where pure vagal activity was assessed by high frequency power (0.15–0.4 Hz). Low frequency power (0.04–0.15 Hz) reflects both parasympathetic and sympathetic control. Effect parameters were recorded before and during random distraction and attention. Distraction from sural nerve stimulation was induced by a mental arithmetic test, paced auditory serial addition task (PASAT), while attention was induced by concentrating on painful foot stimulation. Paced auditory serial addition task decreased mean-RR and SD-NN, frequency domain parameters, as well as pain ( P < 0.001). In contrast, PASAT did not change the spinal withdrawal reflex. Attention did not affect any effect parameter. Distraction by PASAT altered autonomic activity and inhibited pain but failed to affect withdrawal reflex responses, while attention had no effect on either parameter. Psychological distraction and attention may have different effects on noxious evoked pain perception and autonomic activity. Pain relief during PASAT probably involves supraspinal mechanisms. [ABSTRACT FROM AUTHOR]

Background A maladaptation of the autonomic nervous system may been seen in patients with chronic pain that includes persistent changes in the autonomic tone, increased heart rate, and reduced heart rate variability and baroreflex sensitivity. Baroreflex sensitivity and acute pain intensity have been reported to be inversely correlated. However, it is unknown whether the same correlation applies with regard to post-operative pain. In the present study, autonomic function was measured in patients scheduled for minor hand surgery and correlated with early and persistent pain after the procedure. Thus, the cause (autonomic imbalance) was present before the effect (post-operative pain). Our primary hypothesis was that a lower level of pre-operative baroreflex sensitivity is correlated with increased early post-operative pain. Methods There were 30 patients included and scheduled for open carpal tunnel surgery. Baroreflex sensitivity and heart rate variability were measured before surgery. Efferent cardiac parasympathetic activity was estimated by power spectral analysis of heart rate variability. Post-operative pain was recorded daily for 6 weeks (early post-operative pain) and for 1 week 1 year after surgery (persistent post-operative pain). Results Pre-operative baroreflex sensitivity correlated negatively with early ( P = 0.05) and persistent ( P = 0.04) post-operative pain. Efferent cardiac parasympathetic activity correlated negatively with early ( P = 0.03) but not persistent post-operative pain ( P = 0.12). Conclusions The findings suggest that a low pre-operative level of baroreflex sensitivity is associated with higher post-operative pain intensity. To our knowledge, this is the first study to show the correlation between baroreflex sensitivity and post-operative pain. [ABSTRACT FROM AUTHOR]

Mutations in the gene for desmoplakin ( DSP) may cause arrhythmogenic right ventricular cardiomyopathy ( ARVC) and Carvajal syndrome ( CS). Desmoplakin is part of all desmosomes, which are abundantly expressed in both myocardial and epidermal tissue and serve as intercellular mechanical junctions. This study aimed to investigate protein expression in myocardial and epidermal tissue of ARVC and CS patients carrying DSP mutations in order to elucidate potential molecular disease mechanisms. Genetic investigations identified three ARVC patients carrying different heterozygous DSP mutations in addition to a homozygous DSP mutation in a CS patient. The protein expression of DSP in mutation carriers was evaluated in biopsies from myocardial and epidermal tissue by immunohistochemistry. Keratinocyte cultures were established from skin biopsies of mutation carriers and characterized by reverse transcriptase polymerase chain reaction, western blotting, and protein mass spectrometry. The results showed that the mutation carriers had abnormal DSP expression in both myocardial and epidermal tissue. The investigations revealed that the disease mechanisms varied accordingly to the specific types of DSP mutation identified and included haploinsufficiency, dominant-negative effects, or a combination hereof. Furthermore, the results suggest that the keratinocytes cultured from patients are a valuable and easily accessible resource to elucidate the effects of desmosomal gene mutations in humans. [ABSTRACT FROM AUTHOR]

Objective: The aim of this study was to determine the prevalence of moderate ischemic mitral regurgitation (IMR) in the contemporary CABG population. We also aimed to correlate the effective regurgitant orifice area (ERO) of any regurgitant mitral valve in patients with coronary artery disease with the semiquantitative integrated scale of IMR. Design: From March 15 through June 15, 2006, 510 consecutive CABG patients in three tertiary centres were included in the study. All patients showing any sign of mitral regurgitation (MR) at the referring hospital underwent a preoperative transthoracic echocardiographic estimation of the degree of MR using the integrated scale (1-4) and ERO. Results: IMR was found in 141 patients (28%). The prevalence of moderate 2+ or worse IMR was 4% (95% CI; 2.5-6.1%) and the ERO corresponding to 2+ IMR or more ranged from 5 to 30 mm(2). Fourteen patients had an ERO between 15-30 mm(2). Conclusions: According to our study, patients with moderate IMR, defined as an ERO between 15-30 mm(2), account for only 2.7% (95% CI; 1.5-4.7%) of a non-emergency CABG population. [ABSTRACT FROM AUTHOR]

A reduced nocturnal fall in blood pressure (BP) and increased QT dispersion both predict an increased risk of cardiovascular events in diabetic as well as nondiabetic subjects. The relationship between these two parameters remains unclear. The role of diabetic autonomic neuropathy in both QT dispersion and circadian BP variation has been proposed, but data have been conflicting. The aim of the present study was to describe associations between QT dispersion and circadian BP variation as well as autonomic function in type 1 diabetic patients. In 106 normoalbuminuric (urinary albumin excretion <20 microg/min) normotensive patients, we performed 24-h ambulatory BP (Spacelabs 90207) and short-term (three times in 5 min) power spectral analysis of RR interval oscillations, as well as cardiovascular reflex tests (deep breathing test, postural heart rate, and BP response). No patient had received (or had earlier received) antihypertensive or other medical treatment apart from insulin. In a resting 12-lead electrocardiogram, the QT interval was measured by the tangent method in all leads with well-defined T-waves. The measurement was made by one observer blinded to other data. The QT interval was corrected for heart rate using Bazett's formula. The QTc dispersion was defined as the difference between the maximum and the minimum QTc interval in any of the 12 leads. When comparing patients with QTc dispersion below and above the median (43 ms), the latter had significantly higher night BP (114/67 vs. 109/62 mmHg, P < 0.003/P < 0.001), whereas day BP was comparable (129/81 vs. 127/79 mmHg). Diurnal BP variation was blunted in the group with QTc dispersion >43 ms with significantly higher night/day ratio, both for systolic (88.8 vs. 86.2%, P < 0.01) and diastolic (83.1 vs. 79.5%, P < 0.01) BP. The association between QTc dispersion and diastolic night BP persisted after controlling for potential confounders such as sex, age, duration of diabetes, urinary albumin excretion, and HbA1c. Power spectral analysis suggested an altered sympathovagal balance in patients with QTc dispersion above the median (ratio of low-frequency/high-frequency power: 1.0 vs. 0.85, P < 0.01). In normoalbuminuric type 1 diabetic patients, increased QTc dispersion is associated with reduced nocturnal fall in BP and an altered sympathovagal balance. This coexistence may be operative in the ability of these parameters to predict cardiovascular events. [ABSTRACT FROM AUTHOR]

The objective of this study was to estimate the Danish lifetime hospital costs associated with treatment of ATTRm, before and after carriers convert to patients, respectively. The total hospital costs after a carrier convert to patient is US$ 103,294 per patient. [Extracted from the article]

Wild-type transthyretin amyloid cardiomyopathy (ATTRwt) is associated with substantial delays in diagnosis (>4 years in 42% of patients) in which period, patients are frequently hospitalised with cardiac symptoms. We calculate the total hospital costs pre-diagnosis covering 3 years prior to diagnosis and 3.9 years after diagnosis, based on median survival. [Extracted from the article]

Background: Dietary n-3 polyunsaturated fatty acids (PUFA) derived from fish may reduce the incidence of sudden cardiac death (SCD) probably due to an antiarrhythmic effect. However, such an effect of n-3 PUFA has only been sparsely investigated in humans. Methods and Results: We included 98 patients with ischemic heart disease and treated with an implantable cardioverter defibrillator due to a previous serious arrhythmic event. The number of recorded and treated ventricular fibrillation (VF) and ventricular tachycardia (VT) events were assessed during a 12 month period and related to the concentration of marine n-3 PUFA in serum phospholipids. Patients with more than one arrhythmic event had significantly lower n-3 PUFA levels compared to patients without arrhythmias (mean 7.1 % vs 9.2 %, p <0.01). Dividing the patients into quintiles according to their n-3 PUFA level those with the lowest content of n-3 PUFA had more ventricular arrhythmias than patients with the highest concentration of n-3 PUFA (mean 1.3 event vs 0.2 event, p <0.05). In line with this, 33% of the patients in the two lowest n-3 PUFA quintiles developed arrhythmias compared to 18 % in the other quintiles (p< 0.05). Conclusion: Patients with a low content of n-3 PUFA in the blood had a significantly higher incidence of malignant ventricular arrhythmias compared to patients with high blood levels of n-3 PUFA. The data suggest that the protection offered by n-3 PUFA on SCD observed in previous studies is caused by a direct antiarrhythmic effect of n-3 PUFA. [ABSTRACT FROM AUTHOR]