We present a case of 70 years old man with heart conduction disturbances in whom neurological disorder has been previously recognized. The principal causes of loss of consciousness are vascular, cardiac and neurological disorders, rarely metabolic and psychogenic causes occur. In more than ten per cent the cause is not recognized. Diagnosis is based mainly on clinical history, physical examination and noninvasive diagnostic tests, also specialist evaluation. In some cases invasive tests are conclusive. Typical symptoms accompanied by loss of consciousness, such as rapid onset, presence of prodromal signs, cyanosis or pallor, seizures and urinary incontinence, are not specific and can occur in all cases with different intensification, not depending on the cause. In the current case in our patient the presence of convulsive syncope mimicking epilepsy in clinical presentation caused a delay of proper cardiologic diagnosis. The final diagnosis was based on clinical evaluation and noninvasive diagnostic tests. The confirmation of diagnosis was recording total A-V block without substitute rhythm in 24-h Holter monitoring during a syncopal episode. In a patient with trifascicular block in ECG and syncope without other cause of events should be implanted pacemaker according to the Guidelines of the European Society of Cardiology of 2007. A loss of consciousness is an important clinical problem because they are relatively frequently in a daily practice, they are associated with injuries and they can lead to invalidity or event a death of a patient. In most cases even not clear cause can be recognized thanks to diagnostic tests and experience of a doctor and their knowledge of EBM.