Changes of Left Ventricular Diastolic Filling After Sublingual Nitroglycerin in Determining the Severity of Coronary Artery Disease

Abstract

The aim of the study was to evaluate the left ventricular (LV) diastolic filling (DF) in patients with 1, 2, and 3 vessel and left main (LM) coronary artery disease (CAD) and to determine the response of LV DF to nitroglycerin in age‐matched patient groups. The study covers 74 patients with CAD including ten patients with 1 vessel CAD, ten patients with 2 vessel CAD, 43 patients with 3 vessel CAD, and 11 patients with LM CAD who underwent Doppler echocardiographic measurements of early (E) and late (A) diastolic transmitral velocities, their ratio (E/A) and deceleration time (DT) of E before and after sublingual administration of 0.5 mg nitroglycerin. Baseline studies did not reveal any significant differences in E, A, and DT between groups. Baseline E/A ratio differed between 1, 2, and 3 vessel and LM CAD patients (1.07 ± 0.10; 0.89 ± 0.07; 0.87 ± 0.05 vs 0.67 ± 0.06, P < 0.05). After nitroglycerin, significant differences in E between 1 vessel CAD and all the remaining groups, also between 2 and 3 vessel CAD and LM CAD patient groups (50.1 ± 2.4 cm/sec vs 39.6 ± 2.6; 38.4 ± 1.8; 30.2 ± 3.3 cm/sec and 39.6 ± 2.6; 38.4 ± 1.8 cm/sec vs 30.2 ± 3.3 cm/sec, respectively) were observed. A velocity did not differ significantly between the groups, DT differed between 1 vessel CAD and LM CAD patients (162.2 ± 14.6 msec vs 117.0 ± 12.1 msec), differences in E/A ratio appeared between 1 vessel and the remaining groups (1.13 ± 0.10 vs 0.72 ± 0.08; 0.70 ± 0.05 and 0.55 ± 0.07). Thus, Doppler LV DF indices, except E/A ratio, were not sensitive in reflecting the severity of CAD. Therefore, nitroglycerin resulted in more marked decrease of LV DF indices in patients with more severe CAD and in revealing differences between patients with 1, 2, and 3 vessel and LM CAD. These data suggest that a nitroglycerin Doppler test may be proposed for the assessment of the severity of CAD.