Detection of ventricular ectopy in patients with coronary heart disease and normal subjects by exercise testing and ambulatory electrocardiography.

Maximal exercise testing and 24-hour ambulatory electrocardiographic recording (Holter monitor) were utilized in the detection of ventricular ectopy in 90 patients with stable chronic coronary heart disease and in 30 normal subjects. Although the occurrence of any ventricular ectopic activity, as detected by either or both methods, was common, the incidence was significantly higher (P less than 0.001) in patients with coronary heart disease (86 percent; 77/90), as compared to that in normal subjects (40 percent; 12/30). Ventricular arrhythmia was more frequently detected by the 24-hour continuous electrocardiographic recording, being found in 70 of the 90 patients with coronary heart disease and in ten of the 30 normal subjects. In comparison, exercise testing disclosed ventricular ectopy in 56 of the 90 patients with coronary heart disease and in two of the 30 normal subjects. Multiform and repetitive patterns of ventricular ectopy were detected twice as commonly by continuous electrocardiographic recording than with exercise testing, and these patterns were present in one-half of the patients with coronary heart disease. Both methods of examination adjunctively disclosed more ventricular ectopy than either method alone.

Computer analysis of ventricular conduction defects.

Computer criteria for LAHB and LPHB were described together with limits of normal for ortogonal leads. These differ significantly from those used for conventional 12-lead ECG, indicating the need for specific LAHB and LPHB criteria in orthogonal electrocardiography. Multivariate analysis with a likelihood ratio test was used for the separation of records with conduction defects with and without MI. The total number of records was 847. The recognition rate for MI in the presence of LVCD was 66%. In the presence of RVCD, MI was diagnosed correctly in only 55%. This relatively poor result was probably due to the relatively large number of combinations of RCVD with LAHB or LPHB.

Ventricular arrhythmia 24 hours before and after maximal treadmill testing.

To determine if maximal exercise treadmill testing influences the occurence of ventricular arrhythmia in the hours after exercise, 45 myocardial infarction and 22 angina pectoris patients (New York Heart Association Class I-II), and 23 normal subjects were examined with 24-hour ambulatory electrocardiographic Holter recordings before and after exercise testing. Comparison of qualitative and quantitative ventricular arrhythmia detected during identical chronological two-, four-, and 20- or more hour periods, before and after exercise testing in each patient, revealed no statistically significant difference in any patient group. The prevalence of ventricular ectopy in 80 per cent of ischemic heart disease patients and 30 per cent of normal subjects as detected by 24-hour Holter recordings was similar to previous studies. It is concluded that in ambulatory ischemic heart disease patients (New York Heart Association Class I-II) and normal subjects, maximal treadmill testing does not significantly affect the occurrence of ventricular arrhythmia in the hours after exercise.