Cryptogenic stroke and extrasystolic arrythmia: is there any correlation?

Up to 45% of all ischemic strokes (IS) are cryptogenic.

To reveal the possible reasons of cryptogenic IS.

We analyzed the cases of computer tomography verified IS in patients admitted the hospital during the period of 3 years. All these 268 patients had unidentified source of IS. We analyzed hemostasiograms, lipids levels, performed echocardiography, Doppler ultrasound of brachiocephalic arteries, 24-hours ECG monitoring and common carotid arteries sphygmography (SG).

None of the patients had atrial fibrillation, hemodynamically significant stenoses of brachiocephalic arteries or hematological pathology associated with hypercoagulation. 234 (87.3%) patients had atherosclerotic plaques in carotid area bifurcation (in 36 (13.4%) – intima-media thickness was 1.1 mm, in 74 (27.6%)– stenosis <40%, in 124 (46.3%) had 40–69% stenosis in diameter). The internal carotid stenosis in diameter is calculated by ECST, NASCET and St. Mary's ratio criteria. To detect the type of the plaques we used Gray-Weale–Nicolaides ultrasound classification. In 39 (14.5%) was type I: uniformly echolucent plaque; in 88 (32.8%) type II: predominately echolucent plaque; in 71 (26.5%) type III: predominantly echogenic plaque, none had type IV: uniformly echogenic plaque or type V: heavy calcification. In 24-hours ECG monitoring and SG we revealed that most of the patients – 244 (91.0%) had extrasystolic arrhythmia which ventricular contraction of extrasystole appeared in the early phase of cardiocycle – before the transmitral blood flow peak. In 1st post-extrasystolic wave after such extrasystole we detected the growth of linear blood flow speed in carotid bifurcation (2.5 m/sec) and kinetic arteries parameters of SG (2.6 times).

The appearance of IS is higher in patients with extrasystolic arrhythmia appearing in the cardiocycle before the transmitral blood flow peak. In cryptogenic stroke, the reason of it can be the atherosclerotic plaque defragmentation with further embolism, caused by the additional mechanical trauma of increased hemodynamical and kinetic parameters of pulse wave of the 1st post-extrasystolic contraction.

Type of funding sources: None.