Effects of verapamil on left ventricular diastolic filling in children with hypertrophic cardiomyopathy.
The effects of oral verapamil on resting left ventricular (LV) diastolic filling were examined in 10 children and adolescents with hypertrophic cardiomyopathy. Measurements of diastolic filling were made from gated technetium-99m radionuclide angiograms with postbeat rejection of data outside a 5% RR-interval window. LV time-activity curves were generated and the rapid-filling phase fit with a 3 degrees polynomial to calculate the peak filling rate and the time from end-systole to the point of peak filling. All patients had a radionuclide angiogram performed before and after 0.25 to 3 years of oral verapamil therapy. Verapamil did not change the LV ejection fraction but increased the peak filling rate (3.24 +/- 0.15 to 4.62 +/- 1.05 end-diastolic volume/s,p less than 0.01) and reduced the time to peak filling (217 +/- 57 to 168 +/- 63 ms, p less than 0.01). An increase in exercise endurance as measured by exercise treadmill test and subjective symptomatic improvement were also seen after verapamil therapy. Thus, in children with hypertrophic cardiomyopathy, symptomatic improvement and LV diastolic filling parameters improved with long-term oral verapamil.
Shaffer
E M
EM
Department of Pediatric Cardiology, Mott Children's Hospital, University of Michigan Medical Center, Ann Arbor 48109-0204.
Rocchini
A P
AP
Spicer
R L
RL
Juni
J
J
Snider
R
R
Crowley
D C
DC
Rosenthal
A
A
D000284:Administration, Oral; D000293:Adolescent; D002312:Cardiomyopathy, Hypertrophic / Q000000981:diagnostic imaging / Q000188:drug therapy*; D002648:Child; D005080:Exercise Test; D005500:Follow-Up Studies; D006321:Heart / Q000000981:diagnostic imaging; D006801:Humans; D009200:Myocardial Contraction / Q000187:drug effects*; D011875:Radionuclide Angiography; D013667:Technetium; D013997:Time Factors; D014700:Verapamil / Q000627:therapeutic use*
D013667:Technetium; D014700:Verapamil