[Effect of the sinocarotid test on heart bundle-branch block]

The pressing effect of sinus caroticus upon an existing permanent heart bundle branch block is studied. The test was applied on 23 patients with bundle branch block (9 with left and 14- with right). A short-term disappearance of the bundle branch block was observed in five of them, accompanied with sinus bradycardia and in one case the restoration of normal intraventricular conductivity was not accompanied with frequency change. Theoretical reasonings upon the possible explanation of the phenomenon are reported.