TY - JOUR
T1 - Analysis of intracardiac electrograms showing monomorphic ventricular tachycardia in patients with implantable cardioverter-defibrillators
AU - Saeed, Mohammad
AU - Link, Mark S.
AU - Mahapatra, Srijoy
AU - Mouded, Majd
AU - Tzeng, David
AU - Jung, Vivian
AU - Contreras, Robert
AU - Swygman, Craig
AU - Homoud, Munther
AU - Mark Estes, N. A.
AU - Wang, Paul J.
PY - 2000/3/9
Y1 - 2000/3/9
N2 - Ventricular tachycardia (VT) initiation and its relation to various clinical factors was studied by reviewing infracardiac electrograms from patients with implantable cardioverter-defibrillators. Events were divided into (1) sudden onset without preceding ventricular premature complexes (VPCs), (2) extrasystolic onset with VPCs, or (3) paced, depending on the type and morphology of the last 5 beats before initiation of VT. Prematurity index, sinus rate, cycle length, and presence of shorf-long-short sequence for each episode was noted. A total of 268 episodes of VT among 52 patients were analyzed. Extrasystolic initiation was the most frequent pattern (177; 66%) followed by sudden onset (75; 28%) and paced (16; 6%). Among extrasystolic onset, 99 episodes (56%) were due to multiple VPCs and 149 episodes (84%) had different VPC morphology than the subsequent VT. Among pacing-induced VT, 13 of 16 episodes were due to inappropriate pacing due to undersensing of prior R waves. Sudden-onset episodes were slower (mean cycle length 383 ± 97 ms) than extrasystolic (mean cycle length 336 ± 88 ms, p = 0.002) and paced (mean cycle length 313 ± 85 ms, p = 0.01) onset. Patients in the sudden-onset group had better left ventricular ejection fraction (33 ± 15%) than the extrasystolic (29 ± 11%, p < 0.001) and paced (28 ± 14%, p < 0.01) groups. Extrasystolic onset with multiple, late coupled VPCs was the most common pattern of VT initiation and was associated with lower ejection fraction. Sudden-onset initiation was more common with better preserved systolic function.
AB - Ventricular tachycardia (VT) initiation and its relation to various clinical factors was studied by reviewing infracardiac electrograms from patients with implantable cardioverter-defibrillators. Events were divided into (1) sudden onset without preceding ventricular premature complexes (VPCs), (2) extrasystolic onset with VPCs, or (3) paced, depending on the type and morphology of the last 5 beats before initiation of VT. Prematurity index, sinus rate, cycle length, and presence of shorf-long-short sequence for each episode was noted. A total of 268 episodes of VT among 52 patients were analyzed. Extrasystolic initiation was the most frequent pattern (177; 66%) followed by sudden onset (75; 28%) and paced (16; 6%). Among extrasystolic onset, 99 episodes (56%) were due to multiple VPCs and 149 episodes (84%) had different VPC morphology than the subsequent VT. Among pacing-induced VT, 13 of 16 episodes were due to inappropriate pacing due to undersensing of prior R waves. Sudden-onset episodes were slower (mean cycle length 383 ± 97 ms) than extrasystolic (mean cycle length 336 ± 88 ms, p = 0.002) and paced (mean cycle length 313 ± 85 ms, p = 0.01) onset. Patients in the sudden-onset group had better left ventricular ejection fraction (33 ± 15%) than the extrasystolic (29 ± 11%, p < 0.001) and paced (28 ± 14%, p < 0.01) groups. Extrasystolic onset with multiple, late coupled VPCs was the most common pattern of VT initiation and was associated with lower ejection fraction. Sudden-onset initiation was more common with better preserved systolic function.
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U2 - 10.1016/S0002-9149(99)00815-2
DO - 10.1016/S0002-9149(99)00815-2
M3 - Article
C2 - 11078271
AN - SCOPUS:0034153324
SN - 0002-9149
VL - 85
SP - 580
EP - 587
JO - American Journal of Cardiology
JF - American Journal of Cardiology
IS - 5
ER -