Paravertebral Block and the Electrocardiogram in Angina Pectoris

Various surgical procedures in the region of the cervico-thoracic sympathetic system have been proposed for the treatment of angina pectoris. The paravertebral block of the upper thoracic sympathetic ganglia proved to be the most successful and the least dangerous. It was first introduced by Mandl (1925) who, using injections of novocain, reported that he had achieved relief of pain for many weeks. Swetlow (1926) recommended the use of alcohol and thought by this modification to prolong the effect of the paravertebral block. The sensory nerves of the heart and coronary vessels pass through the middle and inferior cardiac nerves to the middle and inferior cervical ganglia. Since there are no white rami com- municantes between the cervical sympathetic chain and the spinal cord these sensory fibres must descend to the upper thoracic ganglia, from where they finally reach the spinal ganglia (Ranson and Billingsley, 1918, and Stohr, 1928). Besides the cervical cardiac nerves, there exist thoracic cardiac nerves which also serve as sensory pathways (Brauecker, 1927; Jonescu, 1927; and White et al., 1933): these nerves pass directly through the posterior mediastinum to the upper four or five thoracic sympathetic ganglia. Thus, all the sensory pathways from the heart converge, uniting in the upper four or five thoracic ganglia. These anatomical facts explain the good results obtained by the paravertebral block of the upper thoracic ganglia (Marvin, 1935; Ochsner and DeBakey, 1937; and Levy and Moore, 1941).