Chronotropic incompetence: real life observations of a theoretical concept.

The concept of chronotropic incompetence may have to be fine-tuned in an era of proven benefit of heart rate reducing therapy. It is illustrated in three patients with heart failure referred for heart transplantation evaluation. In patients one and two, symptoms of heart failure and exercise capacity improved by reducing the dose of the beta-blocking agent (case 1 and 2) and, in patient three, by additionally lowering the dose of amiodarone. Patient three showed reduced exercise tolerance, particularly during cycling albeit not during walking. Exercise tolerance during cycling improved after adaptation of the rate response parameters of his pacemaker. In conclusion, the three cases illustrate that chronotropic incompetence is a clinical reality, while a correct history taking and specific measures can solve the problem, reduce the complaints and even avoid more aggressive therapeutic options such as orthotopic transplantation.