ASSESSMENT OF THE DIASTOLIC FUNCTION BY BODY SURFACE POTENTIAL MAPS IN ISCHEMIC HEART DISEASE

摘要

Impaired left ventricular diastolic function may manifest as left atrial enlargement sign on the ECG. Body surface potential mapping (BSPM) provide a more detailed evaluation. We studied the effect of the nitroglycerin administration in cases with positive exercise test. Method: Seventy-seven patients (59 m, 41-76 y, mean 63) with ischemic heart disease were divided into two groups: 39 patients had positive, 38 patients had negative exercise test. The sum of the greatest maximum and the simultaneous minimum potential of the left atrium was examined with BSPM (using the Montreal system, 63 leads) before and 6 minutes after nitroglycerin administration and were evaluated by t-test for dependent samples. Results: We found a mean 27+-11% decrease (p<0.0001) due to nitroglycerin effect in the group of positive exercise test. There was no significant change in the group with negative exercise test. The difference between the two groups was significant (p<0.0001). For clinical evaluation, a corrigated separating score was established: >15% change indicates exercise test positivity with 97% sensitivity and 100% specificity. Conclusion: The significant decrease of the atrial electrical parameter caused by nitroglycerin admission indicates exercise test positivity and may provide a new resting method avoiding the risk of the exercise test.