Internally Recorded Systolic Time Intervals in Hypertrophic Subaortic Stenosis
MILTIADIS A. STEFADOUROS, FACC MARIO 1. CANEDO, MD ELIAS KARAYANNIS, ABDULLA ABDULLA,
MD,
MD MD
MARTlN J. FRANK, MD, FACC Augusta,
Georgia
From the Section of Cardiology, Department of Medicine, Medical College of Georgia, Augusta, Georgia. Manuscript received March 17, 1977; revised manuscript received May 20, 1977, accepted May 31, 1977. Address for reprints: Miltiadis A. Stefadouros, M.D., Associate Professor of Medicine, Medical College of Georgia, Augusta, Georgia, 30901.
700
November1977
The cardiac catheterization records of 20 patients with documented hypertrophic subaortic stenosis were analyzed to evaluate the utility of systolic time intervals in quantitating left ventricular outflow tract obstruction in this disease. The preejection period, ejection time and instantaneous peak outflow pressure gradient were measured from simultaneous recordings of the electrocardiogram and left ventricular and central aortic pressure signals, and the preejection period/ejection time (PEP/ET) ratio was computed. Most patients had a significant spontaneous or induced (with isoproterenol or postextrasystolic potentiation) variation in peak outflow gradient (range 0 to 186, average 85 mm Hg) with a high linear correlation between the peak outflow gradient and the systolic time intervals. For the group, peak outflow gradient correlated best with PEP/ET ratio (r = -0.82, no. = 183) and less well with preejection period (r = -0.62), ejection time (r = 0.56) or their rate-corrected values (r = -0.71 and r = 0.60, respectively j. The PEP/ET ratio for beats recorded at the time of cardiac output measurement correlated with instantaneous mean outflow pressure gradient (r = -0.88, no. = 28, P KO.001) and calculated left ventricular outflow orifice size (r = 0.72, no. = 28, P
MILTIADIS A. STEFADOUROS, FACC MARIO 1. CANEDO, MD ELIAS KARAYANNIS, ABDULLA ABDULLA,
MD,
MD MD
MARTlN J. FRANK, MD, FACC Augusta,
Georgia
From the Section of Cardiology, Department of Medicine, Medical College of Georgia, Augusta, Georgia. Manuscript received March 17, 1977; revised manuscript received May 20, 1977, accepted May 31, 1977. Address for reprints: Miltiadis A. Stefadouros, M.D., Associate Professor of Medicine, Medical College of Georgia, Augusta, Georgia, 30901.
700
November1977
The cardiac catheterization records of 20 patients with documented hypertrophic subaortic stenosis were analyzed to evaluate the utility of systolic time intervals in quantitating left ventricular outflow tract obstruction in this disease. The preejection period, ejection time and instantaneous peak outflow pressure gradient were measured from simultaneous recordings of the electrocardiogram and left ventricular and central aortic pressure signals, and the preejection period/ejection time (PEP/ET) ratio was computed. Most patients had a significant spontaneous or induced (with isoproterenol or postextrasystolic potentiation) variation in peak outflow gradient (range 0 to 186, average 85 mm Hg) with a high linear correlation between the peak outflow gradient and the systolic time intervals. For the group, peak outflow gradient correlated best with PEP/ET ratio (r = -0.82, no. = 183) and less well with preejection period (r = -0.62), ejection time (r = 0.56) or their rate-corrected values (r = -0.71 and r = 0.60, respectively j. The PEP/ET ratio for beats recorded at the time of cardiac output measurement correlated with instantaneous mean outflow pressure gradient (r = -0.88, no. = 28, P KO.001) and calculated left ventricular outflow orifice size (r = 0.72, no. = 28, P
