A Syndrome Due to Transient or Changing Heart-block

Abstract

EPIDURAL ANALGESIA BRrIISH event 40 minutes or even longer after epidural injection of what might have seemed a not too excessiv_e dose in a patient of normal biological age. SummaryInjection of local anaesthetic solutions into the spinal extradural space results in a segmental type of analgesia.In normal subjects the number of analgesic dermatomos can be predicted with an accuracy of 15 to 30(,%b in terms of age and the concentration and volume of local anaesthetic used. The amount of local anaesthetic required to block a given area declines steadily after the second decade, in a manner reminiscent of some other curves relating biological phenomena to age. Fifty-three patients with occlusive vascular disease reacted abnormally to epidural analgesia. They behaved as if they were 25 to 50 years older than their chronological age, or as if the injected solution had been twice the concentration actually used. In these patients segmental analgesia spread one and a half to three times further than in normal subjects of the same age. This tendency to increased spread can be hazardous if the anaesthetist is not aware of the necessity for reduced dosage in arteriosclerotic patients.The timen taken for epidural analgesia to reach its farthest limits varies quite widely in normal subjects, and does not appear to be dependent on age. This time interval is prolonged in arteriosclerotic patients.The significance of these findings is discussed in relation to the effects of ageing processes, and to the site of action of epidural analgesia. Rec., 68, 63. C-escitelli, F. (1951). Amer. J. Physiol., 166, 229. de Saram, M. (1956). Anaesthzesia, 11, 77. Downie, A. W., and Newell, D. J. (1961). Neuraology (AMinntzeap.), 11, 876. Dyrbye, M. 0. (1959 PhYsician to Charing Cross Hospital, LondonzIt is well recognized that angina pectoris can occur with the paroxysmal tachycardias. Pain can also be a direct result of heart-block, the pain and the block starting and ending at the same time. Four cases of transient or changing heart-block are reported. Two of the patients had normal cardiograms at rest and had severe pain only when exertion was associated with a 2: 1 heart-block. The pain was described as bursting, relieved by a varying period of rest but not by trinitroglycerin, and radiating to the neck and down the arms. The pain was associated with the sudden onset of severe dyspnoea, palpitations, a feeling of marked faintness, weakness of the limbs, and alarm. In the other two cases symptoms were associated with a change from 2: 1 to a complete heart-block.Froment et al. (1959) report three cases of anginal pain associated with heart-block but without evidence of coronary artery disease. They believe that myocardial anoxia results from the decrease in coronary blood flow with the abrupt slowing of the heart rate. This is discussed later.Exercise has an important effect on the ventricular rate in both complete and partial heart-block. It was once thought that the bradycardia of complete heart-block was quite unaltered during exe...

Aetiology of Complete Heart-block

“…This is supported by the papers of Froment et al (1959) and Fowler (1962). Although the work of Starzl et al (1955) suggests that in heart-block the coronary flow diminishes pari passu with the work of the heart so that angina should not occur, yet if there were a minor coronary narrowing the effect of this reduction in flow might be exaggerated.…”

Aetiology of chronic heart block. A clinico-pathological correlation in 65 cases.

“…For example, 6 patients with isolated disease of the conducting tissue had angina of effort and all 3 patients with collagen disease had angina of effort and electrocardiograms suggesting diaphragmatic infarction. It is possible that exercise can cause angina by a change of rhythm, and it precipitates block in some patients (Fowler, 1962). It is more likely, however, that there is some other unrecognized cause for the angina.…”

Bradycardiac Angina: Haemodynamic Aspects and Treatment

“…Haemodynamic studies were made at rest, on exertion, and at varying rates of atrial pacing. Though angina as a symptom in bradycardia has been mentioned previously (Hewlett, 1907 ;Stokes, 1909 ;Cowan, 1939 ;Bouvrain et al, 1967;Silverman et al, 1968), it has only twice been recognized that the anginal pain can be the direct consequence of the slow heart rate (Froment et al, 1959;Fowler, 1962). This is the first haemodynamic study of this condition.…”

“…Anginal pain can be the direct result of bradycardia due to transient heart block (Fowler, 1962). While doing exercise tests on patients with the appropriate symptoms to find further examples of bradycardiac angina associated with heart block, a second group of patients was discovered in whom there was a bradycardia at rest with no significant change in the rate on exertion.…”