Little information is available about the relation between right ventricular infarction (RVI) and the presence of atrioventricular block. Thus, the objective of this study was to analyse a possible correlation between the conditions, which are frequently associated with inferior acute myocardial infarction (AMI).Methods
We studied 107 patients with inferior AMI, of whom 49 had RVI, assessed by ST-segment elevation in right precordial leads (V3R-V4R) and by technetium-99m (99mTc) pyrophosphate scintigraphy. The diagnosis of atrioventricular block was made by continuous ECG monitoring during the first week of admission.Results
The patients were divided into two groups: group A with RVI and group B with isolated inferior AMI. These groups were similar regarding sex, age, coronary risk factors, and time from the onset of precordial pain to hospital admission. Group A had a predominance of atrioventricular block (61.2 versus 15.5%, P < 0.0004), peak creatine kinase MB (82.5 ± 22.4 versus 65.2 ± 25.1 IU/I, P< 0.05), congestive heart failure or cardiogenic shock (57.1 versus 18.9%, P < 0.002), and proximal right coronary artery occlusion (80.4 versus 25.0%, P < 0.001). Non-Q-wave infarction was more frequent in group B patients (14.2 versus 34.4%, P < 0.01). The mortality rate was similar in the two groups (12.2 versus 13.7%).Conclusions
These data suggest that infarction extension from inferior wall to the right ventricle may be related to the development of atrioventricular block and does not increase mortality.