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Comparison between the effect of postextrasystolic potentiation and the effect of nitrates on left ventricular
Insights
The postextrasystolic beat (PES) is a superior method to isosorbide dinitrate (ISDN) for differentiating reversible and irreversible left ventricular (LV) asynergy in coronary heart disease patients. PES provides a more precise assessment of viable myocardium.
Area of Science:
- Cardiology
- Cardiovascular Imaging
- Diagnostic Techniques
Background:
- Differentiating reversible and irreversible left ventricular (LV) asynergy is crucial in managing coronary heart disease (CHD).
- Assessing regional and global LV function is key to understanding myocardial viability.
Purpose of the Study:
- To investigate and compare the effectiveness of the postextrasystolic beat (PES) and isosorbide dinitrate (ISDN) in evaluating LV asynergy.
- To determine which method offers a more precise distinction between reversible and irreversible LV dyskinesis.
Main Methods:
- LV angiography was performed in 24 patients before and after ISDN administration.
- Ejection fraction (EF) and regional LV performance (axis shortening) were measured in sinus beats, post-ISDN, and in the PES.
- Analysis included patients with normal LV function and those with CHD and LV asynergy.
Main Results:
- Both ISDN and PES improved ejection fraction in patients with CHD and LV asynergy.
- PES demonstrated a more significant improvement in EF (.57 +/- .13) compared to ISDN (.47 +/- .13).
- PES improved more asynergic myocardial segments (26/39) than ISDN (23/39), indicating better assessment of viable myocardium.
Conclusions:
- The postextrasystolic beat (PES) is more effective than isosorbide dinitrate (ISDN) in assessing myocardial viability.
- PES is simpler to perform and offers a more precise differentiation of reversible versus irreversible left ventricular dyskinesis.
- PES impacts viable myocardium more significantly, aiding in accurate diagnosis for coronary heart disease patients.
Abstract:
In patients with coronary heart disease (CHD) it is important to differentiate between reversible and irreversible left ventricular (LV) asynergy. Therefore global and regional LV function was investigated in the postextrasystolic beat (PES) and after isosorbide dinitrate (ISDN). In 24 patients LV angiograms were performed before and after ISDN. The ejection fraction (EF) was determined in a sinus beat and in PES. Regional LV performance was measured by the shortening of the length axis and six short hemiaxes. In 12 patients with normal LV function at rest EF increased from .72 +/- .04 (+/- 1 SD) to .77 +/- .04 (P less than 0.05) after ISDN and rose further to .81 +/- .02 in the PES (P less than 0.05). In 12 patients with CHD and LV asynergy EF increased from .43 +/- .12 to .47 +/- .13 after ISDN (P less than 0.05) and rose further to .57 +/- .13 in the PES (P less than 0.02). After ISDN 23/39 asynergic axes improved, 15/39 axes did not change, 1/39 axis decreased its shortening by 12%. In the PES 26/39 axes improved, 6/39 axes did not change; 7/39 axes showed less shortening, presumably due to a systolic shift of blood into dyskinetic regions with LV scar. It is concluded: The PES affects viable myocardium more than does ISDN; the PES is easier to perform and permits a more precise distinction between reversible and irreversible LV dyskinesis.