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Repetitive beating after single ventricular extrastimuli: Incidence and prognostic significance in patients with recurrent ventricular tachycardia
ABSTRACTS
REPETITIVE BEATING AFTER SINGLE VENTRICULAR EXTRASTIMULI: INCIDENCE AND PROGNOSTIC SIGNIFICANCE IN PATIENTS WITH RECURRENT VENTRICULAR TACHYCARDIA Jay W. Mason,MD,FACC, Stanford University, Stanford, CA.
MONDAY, MARCH 10, 1980 PM RADIONUCLIDE ANGIOGRAPHY 2:00-5:30
We have tabulated the incidence of repetitiveventricular beating in 59 patients with recurrent ventricular tachycardia in response to programmed single ventricularextrastimuli delivered during spontaneous rhythm to clarify a controversy regarding frequency and prognostic signifiThe 44 males and 15 cance of ventricular repetitions. females had an average age of 51.7 (range 16-75) years. Thirty-four had ischemic heart disease, 28 with prior myocardial infarction; 25 had non-ischemic disease,(8 cardiomyopathies, 8 no identifiable heart disease, 6 valve disease and 3 QT prolongation syndrome.)
DETERMINATION OF ABSOLUTE LEFT VENTRlCUlAR VOLUME FROM GATED BLOOD POOL IMAGING WITH AN ATTENUATION CORRECTED COUNT RATE METHOD Jonathan M. Links, BA; Lewis C. Becker, MD, FACC; J. Gregory Schindledecker, CNMT; Pablo Guzman, MD; Robert D. BUIOW, BS; Edward L. Nickoloff, ScD; Philip 0. Aldemon, MD; and Henry N. Wagner, Jr., MD. The Johns Hopkins Medical Institutions, Baltimore, Maryland.
Repetitive beating occurred in only 9 (15%) of the patients. The repetitive response seemed to be clearly a result of bundle branch reentry in 4 subjects, and possibly due to other mechanisms in 5. There was no difference in the incidence of repetitive beating or in the type of repetitive response in patients with compared to patients without ischemic heart disease. During an average follow-up period of 13.6 months per patient, there Life table anwere 8 sudden and 6 non-sudden deaths. alysis revealed a significantly higher incidence of sudden death in patients with ischemic heart disease compared to subjects with non-ischemic cardiac disease. There was no significant difference in the incidence of sudden death in patients with compared to patients without repetitive beating. We conclude that the repetitive response to single ventricular extrastimulation is infrequent in patients with recurrent ventricular tachycardia, and that repetitive beating is not a prognostic indicator or an indicator of vulnerability to ventricular tachycardia.
A new method for determination of absolute left ventricular volume (LW)was studied in 22 pts who had gated blood pool (GBP) imaging within 24 hrs of single plane (RAO) contrast ventriculography (CV). LAO 46 and anterior views were acquired. A radioactive marker was placed on the skin over the LV in the LAO view, and imaged during the anterior view. A blood sample was withdrawn during the LAO view, and counted on the collimator face after completion of both views. LW at end-diastole (ED) was given by the ratio of the attenuation corrected LVED count rate in the LAO view to the count rate per ml from the blood sample. The LVED count rate was given by dividing the total backgnxmd corrected counts in the LVED region of interestby the time per EDframetimesthe number of cardiac cycles acquired. Attenuation correctionwas made by dividing the LVED count rate by e-ud(u=uofwater, d=distance from skin markerto center of LV in anterior view divided by sin 46 to yield depth of LV in LAO view). This LVEDV was used to calibrate the LV time-activity curve, yielding LW throughout the cardiac cycle. The correlation
between GBP and CV
EDVwos0.96
(GBP=I.WCV
- I2 ml); between GBP and CV ESV was 0.96 (GBP-I.19CV - I3 ml). This method permits determination of absolute LW without geometric assumptions or the use of a regression equation.
SENSITIVITY AND SPECIFICITY OF PROGRAMMED VENTRICULAR STIMULATION IN PATIENTS WITH VENTRICULAR TACHYCARDIA Christine J. VandePol, MD; Ardeshir Farshidi, MD,FACC; Scott R. Spielman, ND: Allan M. Greens~an. MD; Leonard N. Horowitz, MD,FACC; John A. Kastor, MD,FACC: Mark E. Josephson, MD,FACC, Hospital of the University of Pennsylvania, Philadelphia, Pa. Programmed ventricular stimulation (PVS) has been used to evaluate patients (pts) with suspected or documented vantricular tachycardia (VT), however its sensitivity and specificity has not been assessed in a large group of pts. PVS including single and double premature stimuli and rapid pacing was performed in 529 pts during electrophysiSymptomatic clinical VT had been documented ologic study. Clinical VT was sustained (VT-S) in 57 pts and in 86 pts. Of the pts with VT-S nonsustained (VT-NS) in 29 pts. clinically, PVS induced VT-S in 52/57 (91%) pts and VT-NS In 3/57 (5%) of these pts no VT was inin 2/57 (4%) pts. Of the pts with VT-NS clinically, PVS induced duced. VT-NS in 18/29 (62%) pts, in the remaining 11 pts (38%) no VI was induced. Thus, PVS is highly sensitive in identifying pts with VT-S and moderately sensitive for pts with In the 529 pts, VT was induced in 75 pts, 72 of VT-NS. All 52 pts with induced VT-S hadVT whom had clinical VT. clinically and 20/23 (87%) pts with induced VT-NS had VT QRS morphology and axis and tachycardia cycle clinically. lengths of the induced and clinical VTs were similar in each pt. VT-NS was induced in 3/443 (0.7%) pts without clinically documented VT. Thus, PVS is highly specific for identifying pts with VT, either sustained or nonsustained. We conclude that VT resembling clinical VT can be induced by PVS in almost all pts with VT-S clinically, in many pts with symptomatic VT-NS clinically, and rarely in pts without previously documented VT. MO?XOVeT, induction of VT by PVS predicts its clinical occurrence.
February
VIEWER SPECIFIED PROJECTION: A NEW METHOD OF COMPUTER DISPLAY OF LAO ACQUIRED GATED BLOOD POOL DATA IN ANY PROJECTION DESIRED Robert A. Voqel, MD; David M. Stern, BA; Dennis L. Kirch, MSEE; Michael T. LeFree, BS; Peter P. Steele, MD Veterans Administration Medical Center, Denver, CO. A new method is presented for the computerized display of gated blood pool cineangiograms obtained in the LAO projection into any view specified by the observer. The method is based upon tomographic acquisition of 8 frame per cardiac cycle gated blood pool data using the 7 pinhole collimator - scintillation camera technique. Initially, tomographic cineangiograms are reconstructed for each of 8 planes spaced 1.0-1.5 cm apart. Using maximum radial gradient criteria, the edge of the left ventricle (LV) is then determined by the computer for each frame, which results in a complete spatial map of the LV surface in 3 dimensions. Once accomplished, the ventricular surface can be reprojected as it would be viewed from any point in space, including from inside the ventricle. Surface contours are made distinguishable by use of shading determined using light reflectivity criteria. Included in this process is the determination of the LV volume for each tomographic section and for the whole LV. Volumes calculated by this method correlated well (r=.98) with those of 8 ventricular phantoms of from 65 to 210 cc Of the innumerable views into which gated capacity. blood pool studies can be reprojected, the RAO, LPO, and inferior surface views appear to be the most clinically relevant. The latter, which cannot be obtained directly by any conventional methods, is particularly helpful for determination of the septal extent of apical aneurysms. Finally, multiple viewer specified projections can be displayed simultaneously, all obtained from a single LAO projection initial acquisition.
1980
The American Journal of CARDIOLOGY
Volume 45
407
REPETITIVE BEATING AFTER SINGLE VENTRICULAR EXTRASTIMULI: INCIDENCE AND PROGNOSTIC SIGNIFICANCE IN PATIENTS WITH RECURRENT VENTRICULAR TACHYCARDIA Jay W. Mason,MD,FACC, Stanford University, Stanford, CA.
MONDAY, MARCH 10, 1980 PM RADIONUCLIDE ANGIOGRAPHY 2:00-5:30
We have tabulated the incidence of repetitiveventricular beating in 59 patients with recurrent ventricular tachycardia in response to programmed single ventricularextrastimuli delivered during spontaneous rhythm to clarify a controversy regarding frequency and prognostic signifiThe 44 males and 15 cance of ventricular repetitions. females had an average age of 51.7 (range 16-75) years. Thirty-four had ischemic heart disease, 28 with prior myocardial infarction; 25 had non-ischemic disease,(8 cardiomyopathies, 8 no identifiable heart disease, 6 valve disease and 3 QT prolongation syndrome.)
DETERMINATION OF ABSOLUTE LEFT VENTRlCUlAR VOLUME FROM GATED BLOOD POOL IMAGING WITH AN ATTENUATION CORRECTED COUNT RATE METHOD Jonathan M. Links, BA; Lewis C. Becker, MD, FACC; J. Gregory Schindledecker, CNMT; Pablo Guzman, MD; Robert D. BUIOW, BS; Edward L. Nickoloff, ScD; Philip 0. Aldemon, MD; and Henry N. Wagner, Jr., MD. The Johns Hopkins Medical Institutions, Baltimore, Maryland.
Repetitive beating occurred in only 9 (15%) of the patients. The repetitive response seemed to be clearly a result of bundle branch reentry in 4 subjects, and possibly due to other mechanisms in 5. There was no difference in the incidence of repetitive beating or in the type of repetitive response in patients with compared to patients without ischemic heart disease. During an average follow-up period of 13.6 months per patient, there Life table anwere 8 sudden and 6 non-sudden deaths. alysis revealed a significantly higher incidence of sudden death in patients with ischemic heart disease compared to subjects with non-ischemic cardiac disease. There was no significant difference in the incidence of sudden death in patients with compared to patients without repetitive beating. We conclude that the repetitive response to single ventricular extrastimulation is infrequent in patients with recurrent ventricular tachycardia, and that repetitive beating is not a prognostic indicator or an indicator of vulnerability to ventricular tachycardia.
A new method for determination of absolute left ventricular volume (LW)was studied in 22 pts who had gated blood pool (GBP) imaging within 24 hrs of single plane (RAO) contrast ventriculography (CV). LAO 46 and anterior views were acquired. A radioactive marker was placed on the skin over the LV in the LAO view, and imaged during the anterior view. A blood sample was withdrawn during the LAO view, and counted on the collimator face after completion of both views. LW at end-diastole (ED) was given by the ratio of the attenuation corrected LVED count rate in the LAO view to the count rate per ml from the blood sample. The LVED count rate was given by dividing the total backgnxmd corrected counts in the LVED region of interestby the time per EDframetimesthe number of cardiac cycles acquired. Attenuation correctionwas made by dividing the LVED count rate by e-ud(u=uofwater, d=distance from skin markerto center of LV in anterior view divided by sin 46 to yield depth of LV in LAO view). This LVEDV was used to calibrate the LV time-activity curve, yielding LW throughout the cardiac cycle. The correlation
between GBP and CV
EDVwos0.96
(GBP=I.WCV
- I2 ml); between GBP and CV ESV was 0.96 (GBP-I.19CV - I3 ml). This method permits determination of absolute LW without geometric assumptions or the use of a regression equation.
SENSITIVITY AND SPECIFICITY OF PROGRAMMED VENTRICULAR STIMULATION IN PATIENTS WITH VENTRICULAR TACHYCARDIA Christine J. VandePol, MD; Ardeshir Farshidi, MD,FACC; Scott R. Spielman, ND: Allan M. Greens~an. MD; Leonard N. Horowitz, MD,FACC; John A. Kastor, MD,FACC: Mark E. Josephson, MD,FACC, Hospital of the University of Pennsylvania, Philadelphia, Pa. Programmed ventricular stimulation (PVS) has been used to evaluate patients (pts) with suspected or documented vantricular tachycardia (VT), however its sensitivity and specificity has not been assessed in a large group of pts. PVS including single and double premature stimuli and rapid pacing was performed in 529 pts during electrophysiSymptomatic clinical VT had been documented ologic study. Clinical VT was sustained (VT-S) in 57 pts and in 86 pts. Of the pts with VT-S nonsustained (VT-NS) in 29 pts. clinically, PVS induced VT-S in 52/57 (91%) pts and VT-NS In 3/57 (5%) of these pts no VT was inin 2/57 (4%) pts. Of the pts with VT-NS clinically, PVS induced duced. VT-NS in 18/29 (62%) pts, in the remaining 11 pts (38%) no VI was induced. Thus, PVS is highly sensitive in identifying pts with VT-S and moderately sensitive for pts with In the 529 pts, VT was induced in 75 pts, 72 of VT-NS. All 52 pts with induced VT-S hadVT whom had clinical VT. clinically and 20/23 (87%) pts with induced VT-NS had VT QRS morphology and axis and tachycardia cycle clinically. lengths of the induced and clinical VTs were similar in each pt. VT-NS was induced in 3/443 (0.7%) pts without clinically documented VT. Thus, PVS is highly specific for identifying pts with VT, either sustained or nonsustained. We conclude that VT resembling clinical VT can be induced by PVS in almost all pts with VT-S clinically, in many pts with symptomatic VT-NS clinically, and rarely in pts without previously documented VT. MO?XOVeT, induction of VT by PVS predicts its clinical occurrence.
February
VIEWER SPECIFIED PROJECTION: A NEW METHOD OF COMPUTER DISPLAY OF LAO ACQUIRED GATED BLOOD POOL DATA IN ANY PROJECTION DESIRED Robert A. Voqel, MD; David M. Stern, BA; Dennis L. Kirch, MSEE; Michael T. LeFree, BS; Peter P. Steele, MD Veterans Administration Medical Center, Denver, CO. A new method is presented for the computerized display of gated blood pool cineangiograms obtained in the LAO projection into any view specified by the observer. The method is based upon tomographic acquisition of 8 frame per cardiac cycle gated blood pool data using the 7 pinhole collimator - scintillation camera technique. Initially, tomographic cineangiograms are reconstructed for each of 8 planes spaced 1.0-1.5 cm apart. Using maximum radial gradient criteria, the edge of the left ventricle (LV) is then determined by the computer for each frame, which results in a complete spatial map of the LV surface in 3 dimensions. Once accomplished, the ventricular surface can be reprojected as it would be viewed from any point in space, including from inside the ventricle. Surface contours are made distinguishable by use of shading determined using light reflectivity criteria. Included in this process is the determination of the LV volume for each tomographic section and for the whole LV. Volumes calculated by this method correlated well (r=.98) with those of 8 ventricular phantoms of from 65 to 210 cc Of the innumerable views into which gated capacity. blood pool studies can be reprojected, the RAO, LPO, and inferior surface views appear to be the most clinically relevant. The latter, which cannot be obtained directly by any conventional methods, is particularly helpful for determination of the septal extent of apical aneurysms. Finally, multiple viewer specified projections can be displayed simultaneously, all obtained from a single LAO projection initial acquisition.
1980
The American Journal of CARDIOLOGY
Volume 45
407