Improving the efficiency and safety of direct current cardioversion

This ph.d. project has the following aims:

1.  Investigate the cardioversion efficiency and safety of a pulsed biphasic waveform compared with a biphasic truncated exponential waveform.

2. Investigate the cardioversion efficiency and safety of maximum-fixed shocks (360-360-360 J) versus a standard escalating shock protocol with low initial energy selection (125-150-200 J)

3. Investigate the cardioversion efficacy of anterior-lateral versus anterior-posterior electrode placement in cardioverting atrial fibrillation

Study design and setting

The studies are designed as prospective, randomized, single center studies. Patients are enrolled at Randers Regional Hospital Denmark, in an out-patient clinic performing day case cardioversion of patients with atrial fibrillation. All patients admitted for elective cardioversion of atrial fibrillation were eligible for inclusion. Patients for the substudy 3 are also included from Viborg and Horsens Regional Hospitals.


Patients with atrial fibrillation undergoing elective electrical cardioversion of atrial fibrillation.


1.  Cardioversion using pulsed biphasic or truncated exponential biphasic shocks

2. Cardioversion using maximum-fixed shocks (360-360-360 J) or standard escalating shock protocol with low initial energy selection (125-150-200 J)

3. Cardioversion using either anterior-lateral or anterior-posterior electrode


The primary outcome is efficacy, i.e. the proportion of patients in sinus rhythm one minute after cardioversion and efficacy to discharge. Safety outcomes includes cases of arrhythmias, skin burns, patient reported periprocedural pain or discomfort and changes in troponin I levels (for study 1 and 2).


The studies aim to provide warranted data on the optimal procedure for cardioverting atrial fibrillation. The results are available for study 1 and study 2 and has been published in Journal of the American Heart Association and European Heart Journal (#1 ranking cardiovascular journal, impact factor >24). The study results are directly implementable and are likely to change clinical practise:

1.     Anders Sjørslev Schmidt, Kasper Glerup Lauridsen, Kasper Adelborg, Peter Torp, Leif Frausing Bach, Simon Munkesø Jepsen, Nete Hornung, Charles Deakin, Hans Rickers, Bo Løfgren: Cardioversion efficacy using Pulsed Biphasic or Biphasic Truncated Exponential Waveforms – a randomized clinical trial, J Am Heart Assoc, 2017, doi: 10.1161/jaha.116.004853.

2.     Anders Sjørslev Schmidt, Kasper Glerup Lauridsen, Peter Torp, Leif Frausing Bach, Hans Rickers, Bo Løfgren: Maximum-fixed energy shocks for cardioverting atrial fibrillation, European Heart Journal, 2019, doi: 10.1093/eurheartj/ehz585.


Principal Investigator and supervisor

Bo Løfgren, professor, ph.d., FESC, FAHA

Randers Regional Hospital

Hans Rickers, clinical Associate professor, consultant

Viborg Regional Hospital

Andi Eie Albertsen, clinical director, consultant, ph.d.

Dorte Svenstrup Møller, consultant, ph.d.

Per Dahl Christensen, consultant

Horsens Regional Hospital

Karen Kaae Dodt, consultant, ph.d.