The function of the cardiac autonomic nervous system can be estimated by various non-invasive electrocardiographic techniques. The activity in the parasympathetic and sympathetic nervous system plays an important role in the pathophysiology of sudden cardiac death, is significantly altered in diabetic patients where it may play a role in blood pressure regulation and other complications. In malignant vasovagal syncope changes in cardiac autonomic balance plays a salutary role in the final pathways of the hemodynamic collaps. However, many of the cause-effect relations are unclarified.

The ECG laboratorium and syncope clinic offers various ECG techniques for the estimation of cardiac autonomic activity primarily based on heart rate variability and investigations of hemodynamic changes in relation to orthostatic stress.
The techniques have been used in the evaluation of the mechanism of atrial fibrillation post CABG; in the role of the autonomic neuropathy in diabetic patients for blood pressure control and other complications; the impact of vagal activity on the cardiac repolarization process; factors of importance for prolonged depolarization – Late Potentials, and the effects of drugs on the cardiac autonomic balance.
There is also an interdisciplinary research cooperation with neurological departments on the role of myocardial ischemia, myocardial fibrosis – late potentials and autonomic abnormalities for the patophysiology of unexplained death in epilepsy, and studies on the changes in and the role of autonomic imbalance in chronic pain disorders. The techniques are also used in the studies of early cardiac changes in neurodegenerative diseases in children.
The findings in studies of the patophysiology of vasovagal syncope have founded an ongoing international clinical study on closed loop pacing in patients with neurocardiogenic syncope.

Heart failure and metabolism

Myocardial and whole body metabolism is deranged in patents with heart failure. These abnormalities may compromise myocardial substrate uptake and energy generation and contribute to progression of disease. Modulation of myocardial substrate uptake in heart failure patients (Wiggers, Am J Physiol 2005; Halbirk, Am J Physiol 2010a) is a potential treatment modality. Hormonal treatment with glucagon-like peptide-1 (GLP-1) is also a field of future research (Halbirk, Am J Physiol 2010b).

Heart Transplantation

Heart transplantion has excellent short and longterm survival. Renal failure is a long term problem related to nephrotoxicity of immunosuppression with calcineurin inhibitors (CNI). New immunosuppressive treatment regimens including proliferation signal inhibitors and sparing of CNI has been shown to improve renal function in maintenance heart transplant patients (Gullestad L et al, Transplantation. 2010). The effect of treatment with a CNI-free immunosuppressive regimen with high dose of a proliferation signal inhibitor is studied in de novo heart transplant patients in a randomized multicenter Scandinavic study (SCHEDULE). Primary endpoints are renal function and coronary intravascular ultrasound parameters.
Genetic changes arestudied in a cohort of heart transplanted patients with dilated cardiomyopathy.

Pulmonary hypertention

Animal models of pulmonary arterial hypertension (monocrotalin) and right ventricular hypertrophy and failure (pulmonary trunk banding) are used in vivo and in vitro in experimental research. Focus is on pathophysiological mechanisms and pharmacological modulation of the pulmonary circulation and right ventricular hypertrophy and failure (Andersen, Eur J Heart Fail 2008)
A number of clinical trials related to PH and chronic lung disease, pulmonary arterial hypertension (SERAPHIN; PATENT; GRIPHON), chronic thromboembolic pulmonary hypertension (CHEST) and PH associated with left heart disease (LEPHT) are ongoing.

Contacts

Roni Nielsen, MD. PhD- student. roni.r.nielsen@gmail.com
Anders Jorsal, MD. PhD- student. andejors@rm.dk
Henrik Wiggers, MD, PhD, DMSci. Associate professor. henrikwiggers@dadlnet.dk
Tenna Gadgård, MD, PhD- student,
Hans Eiskjær, MD, DMSc., Consultant in cardiology. heis@dadlnet.dk
Asger Andersen, MD. PhD- student. asger.andersen@ki.au.dk
Charlotte Uggerhøj Andersen, MD. PhD- student. cua@farm.au.dk
Mads Dam Vildbrad, MS, Scholar student. mads.dam@studmed.au.dk
Sarah Holmboe, MS, Scholar student. holmboe.sarah@gmail.com
Søren Mellemkjær, MD, PhD. soren.mellemkjaer@skejby.rm.dk
Jens Erik Nielsen-Kudsk, MD, DMSci. Associate professor. jenk@dadlnet.dk