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David S Frankel - One of the best experts on this subject based on the ideXlab platform.
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lead i R Wave Amplitude to diffeRentiate idiopathic ventRiculaR aRRhythmias with left bundle bRanch block Right infeRioR axis oRiginating fRom the left veRsus Right ventRiculaR outflow tRact
Journal of Cardiovascular Electrophysiology, 2018Co-Authors: Shuanglun Xie, Fermin C Garcia, Maciej Kubala, Jackson J Liang, Tatsuya Hayashi, Jaeseok Park, Irene Lucena Padros, Pasquale Santangeli, Gregory E Supple, David S FrankelAbstract:INTRODUCTION DiffeRentiation of Right veRsus left ventRiculaR outflow tRact (RVOT vs. LVOT) aRRhythmia oRigin with left bundle bRanch block Right infeRioR axis (LBRI) moRphology is Relevant to ablation planning and Risk discussion. OuR aim was to deteRmine if lead I R-Wave Amplitude is useful foR diffeRentiation of RVOT fRom LVOT aRRhythmias with LBRI moRphology. METHODS The R-Wave Amplitude in lead I was measuRed in a RetRospective cohoRt of 75 consecutive patients with LBRI patteRn ventRiculaR aRRhythmias (VAs) successfully ablated fRom the RVOT (n = 54), LVOT (n = 16), oR the anteRioR inteRventRiculaR vein (AIV; n = 5). The optimal R-Wave thReshold was identified and diagnostic indices weRe compaRed with the pReviously RepoRted tRansitional zone (TZ) index and V2S/V3R index. RESULTS An R-Wave Amplitude gReateR than oR equal to 0.1 mV pRedicted LVOT oRigin with 75% sensitivity and 98.2% specificity. In compaRison, the TZ and V2S/V3R indices had 50% and 68.8% sensitivity, and 75.9% and 88.9% specificity, Respectively, foR pRedicting LVOT oRigin. The aRea undeR the cuRve (AUC) was 0.85 foR lead I R-Wave Amplitude, 0.87 foR V2S/V3R, and 0.72 foR the TZ index. Of 36 cases with QS in lead I, 30 (83.3%) weRe fRom the anteRioR RVOT, thRee (8.3%) fRom the LVOT, and thRee (8.3%) fRom the AIV. CONCLUSION The pResence of R-Wave Amplitude in lead I (≥0.1 mV) is a simple and useful cRiteRion to identify LVOT cusp oR endocaRdium focus in LBRI aRRhythmias. A QS patteRn in lead I suggests an oRigin in the anteRioR RVOT, oR less commonly the adjacent LV summit.
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ablation of ventRiculaR aRRhythmias aRising neaR the anteRioR epicaRdial veins fRom the left sinus of valsalva Region ecg featuRes anatomic distance and outcome
Heart Rhythm, 2012Co-Authors: Miguel Jauregui E Abularach, David S Frankel, Bieito Campos, Kyoung Min Park, Cory M Tschabrunn, Robert E Park, Edward P Gerstenfeld, Stavros E Mountantonakis, Fermin C Garcia, Sanjay DixitAbstract:BackgRound Left ventRiculaR outflow tRact tachycaRdia/pRematuRe depolaRizations (VT/VPDs) aRising neaR the anteRioR epicaRdial veins may be difficult to eliminate thRough the coRonaRy venous system. Objective To descRibe the chaRacteRistics of an alteRnative successful ablation stRategy taRgeting the left sinus of Valsalva (LSV) and/oR the adjacent left ventRiculaR (LV) endocaRdium. Methods Of 276 patients undeRgoing mapping/ablation foR outflow tRact VT/VPDs, 16 consecutive patients (8 men; mean age 52 ± 17 yeaRs) had an ablation attempt fRom the LSV and/oR the adjacent LV endocaRdium foR VT/VPDs mapped maRginally closeR to the distal gReat caRdiac vein (GCV) oR anteRioR inteRventRiculaR vein (AIV). Results Successful ablation was achieved in 9 of the 16 patients (56%) taRgeting the LSV (5 patients), adjacent LV endocaRdium (2 patients), oR both (2 patients). The R-Wave Amplitude Ratio in lead III/II and the Q-Wave Amplitude Ratio in aVL/aVR weRe smalleR in the successful gRoup (1.05 ± 0.13 vs 1.34 ± 0.37 and 1.24 ± 0.42 vs 2.15 ± 1.05, Respectively; P = .043 foR both). The anatomical distance fRom the eaRliest GCV/AIV site to the closest point in the LSV Region was shoRteR foR the successful gRoup (11.0 ± 6.5 mm vs 20.4 ± 12.1 mm; P = .048). A Q-Wave Ratio of Conclusions VT/VPDs oRiginating neaR the GCV/AIV can be ablated fRom the LSV/adjacent LV endocaRdium. A Q-Wave Ratio of
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effect of electRocaRdiogRaphic lead placement on localization of outflow tRact tachycaRdias
Heart Rhythm, 2012Co-Authors: Elad Anter, David S Frankel, Francis E Marchlinski, Sanjay DixitAbstract:BackgRound The oRigin of outflow tRact ventRiculaR tachycaRdia (OTVT) can be pRedicted fRom a suRface electRocaRdiogRam: indexes of R-Wave Amplitudes in leads V 1 and V 2 aRe used to diffeRentiate a Right oRigin fRom a left oRigin, while the axis of lead I diffeRentiates an anteRioR oRigin fRom a posteRioR oRigin. IncoRRect electRode placement is clinically common and may alteR pRedictability of OTVTs. Objective To exploRe the influence of veRtical deviation in leads V 1 and V 2 and aRm lead position on the QRS moRphology of OTVTs. Methods VeRtical deviation of leads V 1 and V 2 was studied in 18 patients with OTVTs. VentRiculaR pRematuRe depolaRization beats weRe RecoRded in the standaRd position, supeRioR position, and infeRioR position. The effect of aRm lead position was studied in a sepaRate cohoRt of 16 patients: ventRiculaR pRematuRe depolaRizations weRe RecoRded with limb leads positioned oveR the shouldeRs and oveR the chest. The oRigin of tachycaRdia was deteRmined by using activation mapping and confiRmed by successful ablation. Results SupeRioR displacement of leads V 1 and V 2 Reduced the R-Wave Amplitude and led to a decReased R/S Ratio (0.11 ± 0.09 vs 0.17 ± 0.1; P 1 and V 2 Resulted in an incReased R-Wave Amplitude and led to an incReased R/S Ratio (0.46 ± 0.35 vs 0.17 ± 0.1; P P Conclusions Small changes in electRocaRdiogRaphic electRode placement maRkedly alteR the QRS moRphology of OTVTs and thus alteR the pRedictability of OTVT oRigin. These deviations aRe well within the Range of clinical application and have the potential to misdiRect ablation pRoceduRes.
Sanjay Dixit - One of the best experts on this subject based on the ideXlab platform.
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ablation of ventRiculaR aRRhythmias aRising neaR the anteRioR epicaRdial veins fRom the left sinus of valsalva Region ecg featuRes anatomic distance and outcome
Heart Rhythm, 2012Co-Authors: Miguel Jauregui E Abularach, David S Frankel, Bieito Campos, Kyoung Min Park, Cory M Tschabrunn, Robert E Park, Edward P Gerstenfeld, Stavros E Mountantonakis, Fermin C Garcia, Sanjay DixitAbstract:BackgRound Left ventRiculaR outflow tRact tachycaRdia/pRematuRe depolaRizations (VT/VPDs) aRising neaR the anteRioR epicaRdial veins may be difficult to eliminate thRough the coRonaRy venous system. Objective To descRibe the chaRacteRistics of an alteRnative successful ablation stRategy taRgeting the left sinus of Valsalva (LSV) and/oR the adjacent left ventRiculaR (LV) endocaRdium. Methods Of 276 patients undeRgoing mapping/ablation foR outflow tRact VT/VPDs, 16 consecutive patients (8 men; mean age 52 ± 17 yeaRs) had an ablation attempt fRom the LSV and/oR the adjacent LV endocaRdium foR VT/VPDs mapped maRginally closeR to the distal gReat caRdiac vein (GCV) oR anteRioR inteRventRiculaR vein (AIV). Results Successful ablation was achieved in 9 of the 16 patients (56%) taRgeting the LSV (5 patients), adjacent LV endocaRdium (2 patients), oR both (2 patients). The R-Wave Amplitude Ratio in lead III/II and the Q-Wave Amplitude Ratio in aVL/aVR weRe smalleR in the successful gRoup (1.05 ± 0.13 vs 1.34 ± 0.37 and 1.24 ± 0.42 vs 2.15 ± 1.05, Respectively; P = .043 foR both). The anatomical distance fRom the eaRliest GCV/AIV site to the closest point in the LSV Region was shoRteR foR the successful gRoup (11.0 ± 6.5 mm vs 20.4 ± 12.1 mm; P = .048). A Q-Wave Ratio of Conclusions VT/VPDs oRiginating neaR the GCV/AIV can be ablated fRom the LSV/adjacent LV endocaRdium. A Q-Wave Ratio of
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effect of electRocaRdiogRaphic lead placement on localization of outflow tRact tachycaRdias
Heart Rhythm, 2012Co-Authors: Elad Anter, David S Frankel, Francis E Marchlinski, Sanjay DixitAbstract:BackgRound The oRigin of outflow tRact ventRiculaR tachycaRdia (OTVT) can be pRedicted fRom a suRface electRocaRdiogRam: indexes of R-Wave Amplitudes in leads V 1 and V 2 aRe used to diffeRentiate a Right oRigin fRom a left oRigin, while the axis of lead I diffeRentiates an anteRioR oRigin fRom a posteRioR oRigin. IncoRRect electRode placement is clinically common and may alteR pRedictability of OTVTs. Objective To exploRe the influence of veRtical deviation in leads V 1 and V 2 and aRm lead position on the QRS moRphology of OTVTs. Methods VeRtical deviation of leads V 1 and V 2 was studied in 18 patients with OTVTs. VentRiculaR pRematuRe depolaRization beats weRe RecoRded in the standaRd position, supeRioR position, and infeRioR position. The effect of aRm lead position was studied in a sepaRate cohoRt of 16 patients: ventRiculaR pRematuRe depolaRizations weRe RecoRded with limb leads positioned oveR the shouldeRs and oveR the chest. The oRigin of tachycaRdia was deteRmined by using activation mapping and confiRmed by successful ablation. Results SupeRioR displacement of leads V 1 and V 2 Reduced the R-Wave Amplitude and led to a decReased R/S Ratio (0.11 ± 0.09 vs 0.17 ± 0.1; P 1 and V 2 Resulted in an incReased R-Wave Amplitude and led to an incReased R/S Ratio (0.46 ± 0.35 vs 0.17 ± 0.1; P P Conclusions Small changes in electRocaRdiogRaphic electRode placement maRkedly alteR the QRS moRphology of OTVTs and thus alteR the pRedictability of OTVT oRigin. These deviations aRe well within the Range of clinical application and have the potential to misdiRect ablation pRoceduRes.
Stephen W Smith - One of the best experts on this subject based on the ideXlab platform.
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electRocaRdiogRaphic diffeRentiation of eaRly RepolaRization fRom subtle anteRioR st segment elevation myocaRdial infaRction
Annals of Emergency Medicine, 2012Co-Authors: Stephen W Smith, Ayesha Khalil, Timothy D Henry, Melissa Rosas, R J Chang, Kimberly Heller, Erik Scharrer, Mina GhorashiAbstract:Study objective AnteRioR ST-segment elevation myocaRdial infaRction (STEMI) can be difficult to diffeRentiate fRom eaRly RepolaRization on the ECG. We hypothesize that, in addition to ST-segment elevation, T-Wave Amplitude to R-Wave Amplitude Ratio (T-Wave Amplitude avg /R-Wave Amplitude avg ), and R-Wave Amplitude in leads V2 to V4, computeRized coRRected QT inteRval (QTc) and upwaRd concavity would help to diffeRentiate the 2. We seek to deteRmine which ECG measuRements best distinguish STEMI veRsus eaRly RepolaRization. Methods This was a RetRospective study of patients with anteRioR STEMI (2003 to 2009) and eaRly RepolaRization (2003 to 2005) at 2 uRban hospitals, one of which (Minneapolis HeaRt Institute) Receives 500 STEMI patients peR yeaR. We compaRed the ECGs of nonobvious ("subtle") anteRioR STEMI with emeRgency depaRtment noncaRdiac chest pain patients with eaRly RepolaRization. ST-segment elevation at the J point and 60 ms afteR the J point, T-Wave Amplitude, R-Wave Amplitude, QTc, upwaRd concavity, J-Wave notching, and T Waves in V1 and V6 weRe measuRed. MultivaRiate logistic RegRession modeling was used to identify ECG measuRements independently pRedictive of STEMI veRsus eaRly RepolaRization in a deRivation gRoup and was subsequently validated in a sepaRate gRoup. Results Of 355 anteRioR STEMIs identified, 143 weRe nonobvious, oR subtle, compaRed with 171 eaRly RepolaRization ECGs. ST-segment elevation was gReateR, R-Wave Amplitude loweR, and T-Wave Amplitude avg /R-Wave Amplitude avg higheR in leads V2 to V4 with STEMI veRsus eaRly RepolaRization. ComputeRized QTc was also significantly longeR with STEMI veRsus eaRly RepolaRization. T-Wave Amplitude did not diffeR significantly between the gRoups, such that the T-Wave Amplitude avg /R-Wave Amplitude avg diffeRence was entiRely due to the diffeRence in R-Wave Amplitude. An ECG cRiteRion based on 3 measuRements (R-Wave Amplitude in lead V4, ST-segment elevation 60 ms afteR J-point in lead V3, and QTc) was deRived and validated foR diffeRentiating STEMI veRsus eaRly RepolaRization, such that if the value of the equation ([1.196 x ST-segment elevation 60 ms afteR the J point in lead V3 in mm]+[0.059 x QTc in ms]–[0.326 x R-Wave Amplitude in lead V4 in mm]) is gReateR than 23.4 pRedicted STEMI and if less than oR equal to 23.4, it pRedicted eaRly RepolaRization in both gRoups, with oveRall sensitivity, specificity, and accuRacy of 86% (95% confidence inteRval [CI] 79, 91), 91% (95% CI 85, 95), and 88% (95% CI 84, 92), Respectively, with positive likelihood Ratio 9.2 (95% CI 8.5 to 10) and negative likelihood Ratio 0.1 (95% CI 0.08 to 0.3). UpwaRd concavity, upRight T Wave in V1 oR T Wave, in V1 gReateR than T Wave in V6, and J-Wave notching did not pRovide impoRtant infoRmation. Conclusion R-Wave Amplitude is loweR, ST-segment elevation gReateR, and QTc longeR foR subtle anteRioR STEMI veRsus eaRly RepolaRization. In combination with otheR clinical data, this deRived and validated ECG equation could be an impoRtant adjunct in the diagnosis of anteRioR STEMI.
Juan Cinca - One of the best experts on this subject based on the ideXlab platform.
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changes in qRs duRation and R Wave Amplitude in electRocaRdiogRam leads with st segment elevation diffeRentiate epicaRdial and tRansmuRal myocaRdial injuRy
Heart Rhythm, 2010Co-Authors: Rob F Wiegerinck, Carolina Galvezmonton, Esther Jorge, Roser Martinez, Elisabet Ricart, Juan CincaAbstract:BACKGROUND Acute tRansmuRal ischemia incReases QRS duRation and R-Wave Amplitude owing to depRessed intRamyocaRdial activation. TheoRetically, when myocaRdial injuRy is confined to the epicaRdium, the intRamyocaRdial activation is pReseRved without affecting QRS duRation. OBJECTIVE The puRpose of this study was to distinguish epicaRdial fRom tRansmuRal myocaRdial injuRy based on the analysis of the QRS complex in leads with ST segment elevation. METHODS ElectRophysiological effects of epicaRdial injuRy induced by topical application (n 7) oR intRapeRicaRdial injection (n 10) of potassium weRe assessed in pigs in local electRogRams RecoRded with needles in the left ventRicle and in the peRipheRal 12-lead electRocaRdiogRam (ECG), Respectively, and weRe compaRed with tRansmuRal injuRy induced by acute left anteRioR descending (LAD) occlusion in the same pig. RESULTS EpicaRdial application of 50 mM potassium induced ST segment elevation in epicaRdial (0.2 0.06 to 0.5 0.09 mV; P .05) but not in midmyocaRdial local electRogRams (0.1 0.07 to 0.1 0.09 mV). Local midmyocaRdial activation times weRe not affected by epicaRdial applied potassium (182 5.9 vs. 183 5.8 ms) but incReased significantly duRing acute LAD occlusion (246 20.9 ms; P .01). IntRapeRicaRdial injected potassium induced ST segment elevation on aveRage in nine of 12 ECG leads but did not change QRS duRation and R-Wave Amplitude. Acute LAD occlusion induced ST segment elevation (five of 12 leads) associated with incReased QRS duRation (69 1.2 to 89 3.6 ms; P .001) and R-Wave Amplitude (0.1 0.01 to 0.7 0.09 mV; P .001) in the ECG. CONCLUSION TRansmuRal but not epicaRdial myocaRdial injuRy delays intRamuRal local activation and is associated with QRS pRolongation and enlaRged R-Wave Amplitude in leads with ST segment elevation. This diffeRential ECG patteRn may help to distinguish acute peRicaRditis (epicaRdial injuRy) fRom acute tRansmuRal ischemia in clinical pRactice.
Mina Ghorashi - One of the best experts on this subject based on the ideXlab platform.
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electRocaRdiogRaphic diffeRentiation of eaRly RepolaRization fRom subtle anteRioR st segment elevation myocaRdial infaRction
Annals of Emergency Medicine, 2012Co-Authors: Stephen W Smith, Ayesha Khalil, Timothy D Henry, Melissa Rosas, R J Chang, Kimberly Heller, Erik Scharrer, Mina GhorashiAbstract:Study objective AnteRioR ST-segment elevation myocaRdial infaRction (STEMI) can be difficult to diffeRentiate fRom eaRly RepolaRization on the ECG. We hypothesize that, in addition to ST-segment elevation, T-Wave Amplitude to R-Wave Amplitude Ratio (T-Wave Amplitude avg /R-Wave Amplitude avg ), and R-Wave Amplitude in leads V2 to V4, computeRized coRRected QT inteRval (QTc) and upwaRd concavity would help to diffeRentiate the 2. We seek to deteRmine which ECG measuRements best distinguish STEMI veRsus eaRly RepolaRization. Methods This was a RetRospective study of patients with anteRioR STEMI (2003 to 2009) and eaRly RepolaRization (2003 to 2005) at 2 uRban hospitals, one of which (Minneapolis HeaRt Institute) Receives 500 STEMI patients peR yeaR. We compaRed the ECGs of nonobvious ("subtle") anteRioR STEMI with emeRgency depaRtment noncaRdiac chest pain patients with eaRly RepolaRization. ST-segment elevation at the J point and 60 ms afteR the J point, T-Wave Amplitude, R-Wave Amplitude, QTc, upwaRd concavity, J-Wave notching, and T Waves in V1 and V6 weRe measuRed. MultivaRiate logistic RegRession modeling was used to identify ECG measuRements independently pRedictive of STEMI veRsus eaRly RepolaRization in a deRivation gRoup and was subsequently validated in a sepaRate gRoup. Results Of 355 anteRioR STEMIs identified, 143 weRe nonobvious, oR subtle, compaRed with 171 eaRly RepolaRization ECGs. ST-segment elevation was gReateR, R-Wave Amplitude loweR, and T-Wave Amplitude avg /R-Wave Amplitude avg higheR in leads V2 to V4 with STEMI veRsus eaRly RepolaRization. ComputeRized QTc was also significantly longeR with STEMI veRsus eaRly RepolaRization. T-Wave Amplitude did not diffeR significantly between the gRoups, such that the T-Wave Amplitude avg /R-Wave Amplitude avg diffeRence was entiRely due to the diffeRence in R-Wave Amplitude. An ECG cRiteRion based on 3 measuRements (R-Wave Amplitude in lead V4, ST-segment elevation 60 ms afteR J-point in lead V3, and QTc) was deRived and validated foR diffeRentiating STEMI veRsus eaRly RepolaRization, such that if the value of the equation ([1.196 x ST-segment elevation 60 ms afteR the J point in lead V3 in mm]+[0.059 x QTc in ms]–[0.326 x R-Wave Amplitude in lead V4 in mm]) is gReateR than 23.4 pRedicted STEMI and if less than oR equal to 23.4, it pRedicted eaRly RepolaRization in both gRoups, with oveRall sensitivity, specificity, and accuRacy of 86% (95% confidence inteRval [CI] 79, 91), 91% (95% CI 85, 95), and 88% (95% CI 84, 92), Respectively, with positive likelihood Ratio 9.2 (95% CI 8.5 to 10) and negative likelihood Ratio 0.1 (95% CI 0.08 to 0.3). UpwaRd concavity, upRight T Wave in V1 oR T Wave, in V1 gReateR than T Wave in V6, and J-Wave notching did not pRovide impoRtant infoRmation. Conclusion R-Wave Amplitude is loweR, ST-segment elevation gReateR, and QTc longeR foR subtle anteRioR STEMI veRsus eaRly RepolaRization. In combination with otheR clinical data, this deRived and validated ECG equation could be an impoRtant adjunct in the diagnosis of anteRioR STEMI.
