Determination of coronary-myocardial reserve by stress echocardiography in patients with programmed pacemaker
Iskenderov, B.G.; Stepkin, V.A.
Terapevticheskii Arkhiv 72(4): 12-15
2000
ISSN/ISBN: 0040-3660 PMID: 10833790 Document Number: 516845
Aim: To study coronary-myocardial reserve in patients with a programmed pacemaker. Materials and methods: Stress-echocardiography was performed in 64 patients with coronary heart disease (CHD). The stress was induced by a gradual increase in the frequency of electrostimulation (ES) by 10 imp/min from initial 90 imp/min to threshold value which was defined as the frequency threshold of myocardial ischemia induction (FT). Results: Registration of defects in local left ventricular contractility and cardiodynamics in frequent heart ES identified patients with predominant coronary and myocardial failure. Low FT (100-110 imp/min) indicates poor coronary reserve while a considerable rise of the end diastolic pressure in the left ventricle indicates limited myocardial reserve. Positive results of the test in isolated ventricular ES were obtained in 90.9%, in atrial ES in 72.7% of patients. Conclusion: As a highly informative and reproducible method, stress echocardiography can be employed for optimization of antianginal therapy in CHD patients with a pacemaker.