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[Use of poststimulation potentiation during contrast ventriculography in patients with ischemic heart disease]
Insights
Pacemaker stimulation significantly improved left-ventricular volumes and ejection fraction in patients with heart disease. This method is a sensitive, safe alternative for assessing cardiac function in patients with severe heart rate disorders.
Area of Science:
- Cardiology
- Cardiovascular Physiology
Background:
- Assessing left-ventricular function is crucial in patients with heart conditions.
- Traditional exercise tests may pose risks for patients with severe heart rate disorders or myocardial damage.
Purpose of the Study:
- To evaluate left-ventricular volumes and ejection fraction using single ventriculography during and after pacemaker operation.
- To compare the sensitivity and safety of this method with other exercise tests.
Main Methods:
- Single ventriculography was performed on 33 patients in 5 groups based on arterial and myocardial lesion severity.
- Measurements included dp/tdmax, left-ventricular end-systolic volume, end-diastolic volume, and ejection fraction.
- Data were analyzed during pacemaker operation and after device deactivation.
Main Results:
- Final systolic volume significantly changed only in patients with severe coronary arterial disease.
- All groups showed increased final diastolic volume (20-27%) and ejection fraction (7-24%) after stimulation.
- dp/tdmax patterns differed among groups, with distinct differences observed when compared to final diastolic volume based on myocardial contractility.
Conclusions:
- Pacemaker stimulation effectively enhances left-ventricular performance, indicated by increased diastolic volume and ejection fraction.
- The comparison of dp/dtmax and final diastolic volume effectively differentiates groups based on myocardial contractility.
- This ventriculography method is a sensitive, safe, and convenient alternative for assessing cardiac function in high-risk patients.
Abstract:
Patterns of dp/tdmax, left-ventricular volumes and expulsion fraction were examined with the aid of single ventriculography during pacemaker operation and after the device was switched off in 33 patients, divided into 5 groups on the basis of severity of arterial and myocardial lesions. Final systolic volume only changed significantly in patients with sharp coronary arterial changes (group 4). Final diastolic volume increased by 20-27%, and the expulsion fraction, by 7-24%, at post-stimulation potentiation in all the groups. Patterns of dp/tdmax showed differences among the groups. Comparison of dp/dtmax with final diastolic volume revealed a more distinct difference between the groups depending on the severity of changes in myocardial contractility and functional reserves. Compared to other exercise tests this method is more sensitive, convenient and safe for patients with severe heart rate disorders and massive myocardial lesions.