Clinical significance of abnormal postexercise systolic blood pressure response in patients with hypertrophic cardiomyopathy.
The clinical significance of abnormal postexercise systolic blood pressure (SBP) response in patients with hypertrophic cardiomyopathy (HCM) was assessed by treadmill exercise testing in 30 normal subjects and 96 patients with HCM. SBP recovery ratios were derived by dividing the SBP at 1 and 3 min after exercise by the peak exercise SBP. The upper normal limit of the SBP ratio was defined by two standard deviations (SD) from the mean in 30 normal subjects. A postexercise SBP ratio that exceeded the upper normal limits of the SBP ratio was considered to be an abnormal SBP response in patients with HCM. Twenty-seven (28%) of 96 patients with HCM showed an abnormal SBP response. Compared with the normal SBP response group (69 cases) among patients with HCM, the abnormal SBP response group had lower SBP response during exercise (22 +/- 25 vs 62 +/- 26 mmHg : mean +/- 1 SD, p < 0.05), more prolonged QRS width (110 +/- 21 vs 92 +/- 20 msec, p < 0.05), higher incidences of ventricular tachycardia (12 vs 7 cases, p < 0.001), and sudden death (7 vs 0 cases, p < 0.0001). The defect area of Tl-201 myocardial scintigraphy was more extensive in the abnormal SBP response group (2.9 +/- 1.7 segments) than in the normal SBP response group (1.1 +/- 1.3 segments, p < 0.05). During atrial pacing (120/min), pulmonary artery wedge pressure was slightly elevated from 10 +/- 2 (at rest) to 14 +/- 3 mmHg (during pacing) (p<0.001), cardiac index showed no significant changes, and time constant T was shortened from 58 +/- 13 to 48 +/- 10 msec (p < 0.001) in the normal SBP response group, but in the abnormal SBP response group pulmonary artery wedge pressure was highly elevated from 12 +/- 5 to 20 +/- 3 mmHg (p < 0.0001), cardiac index was decreased from 2.5 +/- 0.7 to 2.1 +/- 0.6 l/min/m2 (p < 0.05), and the time constant T had no significant changes. These observations suggest that patients with HCM and abnormal postexercise SBP response have an abnormal cardiac response during exercise and extensive myocardial damage.
Nezuo
S
S
Division of Cardiology, Department of Medicine, Kawasaki Medical School, Kurashiki.
Inoue
S
S
Kawahara
Y
Y
Tanaka
J
J
Tamura
K
K
Saito
Y
Y
Samukawa
M
M
Sawayama
T
T
D001794:Blood Pressure / Q000502:physiology*; D002304:Cardiac Pacing, Artificial; D002312:Cardiomyopathy, Hypertrophic / Q000000981:diagnostic imaging / Q000503:physiopathology*; D016757:Death, Sudden, Cardiac / Q000209:etiology; D005080:Exercise Test; D005260:Female; D006321:Heart / Q000000981:diagnostic imaging; D006801:Humans; D008297:Male; D008875:Middle Aged; D011877:Radionuclide Imaging; D013794:Thallium Radioisotopes
D013794:Thallium Radioisotopes