BACKGROUND: The left ventricular (LV) lead local electrogram (EGM) delay from the beginning of the QRS complex (QLV) is considered a strong predictor of response to cardiac resynchronization therapy. We have developed a method for fast epicardial QLV mapping during video-thoracoscopic surgery to guide LV lead placement. METHODS: A three-port, video-thoracoscopic approach was used for LV free wall epicardial mapping and lead implantation. A decapolar electrophysiological catheter was introduced through one port and systematically attached to multiple accessible LV sites. The pacing lead was targeted to the site with maximum QLV. The LV free wall activation pattern was analyzed in 16 pre-specified anatomical segments. RESULTS: We implanted LV leads in 13 patients with LBBB or IVCD. The procedural and mapping times were 142 ± 39 minutes and 20 ± 9 minutes, respectively. A total of 15.0 ± 2.2 LV segments were mappable with variable spatial distribution of QLV-optimum. The QLV ratio (QLV/QRSd) at the optimum segment was significantly higher (by 0.17 ± 0.08, p < 0.00001) as compared to an empirical midventricular lateral segment. The LV lead was implanted at the optimum segment in 11 patients (at an adjacent segment in 2 patients) achieving a QLV ratio of 0.82 ± 0.09 (range 0.63-0.93) and 99.5 ± 0.6% match with intraprocedural mapping. CONCLUSION: Video-thoracoscopic LV lead implantation can be effectively and safely guided by epicardial QLV mapping. This strategy was highly successful in targeting the selected LV segment and resulted in significantly higher QLV ratios compared to an empirical midventricular lateral segment.

• Klíčová slova
• cardiac resynchronization therapy, epicardial mapping, heart failure, implantable cardioverter defibrillator, left ventricular lead, thoracoscopic implantation, video,
• MeSH
• blokáda Tawarova raménka diagnóza   patofyziologie   terapie   MeSH
• časové faktory MeSH
• design vybavení MeSH
• epikardiální mapování * MeSH
• funkce levé komory srdeční MeSH
• hrudní chirurgie video-asistovaná * MeSH
• komorový tlak (srdce) MeSH
• lidé středního věku MeSH
• lidé MeSH
• perikard patofyziologie   MeSH
• prediktivní hodnota testů MeSH
• prostředky srdeční resynchronizační terapie * MeSH
• senioři MeSH
• srdeční komory patofyziologie   chirurgie   MeSH
• srdeční resynchronizační terapie * škodlivé účinky   MeSH
• studie proveditelnosti MeSH
• Check Tag
• lidé středního věku MeSH
• lidé MeSH
• mužské pohlaví MeSH
• senioři MeSH
• ženské pohlaví MeSH
• Publikační typ
• časopisecké články MeSH
• hodnotící studie MeSH

BACKGROUND AND OBJECTIVES: Catheter ablation of ventricular tachycardia (VT) may include induction of VT and localization of VT-exit site. Our aim was to assess localization performance of a novel statistical pace-mapping method and compare it with performance of an electrocardiographic inverse solution. METHODS: Seven patients undergoing ablation of VT (4 with epicardial, 3 with endocardial exit) aided by electroanatomic mapping underwent intraprocedural 120-lead body-surface potential mapping (BSPM). Two approaches to localization of activation origin were tested: (1) A statistical method, based on multiple linear regression (MLR), which required only the conventional 12-lead ECG for a sufficient number of pacing sites with known origin together with patient-specific geometry of the endocardial/epicardial surface obtained by electroanatomic mapping; and (2) a classical deterministic inverse solution for recovering heart-surface potentials, which required BSPM and patient-specific geometry of the heart and torso obtained via computed tomography (CT). RESULTS: For the MLR method, at least 10-15 pacing sites with known coordinates, together with their corresponding 12-lead ECGs, were required to derive reliable patient-specific regression equations, which then enabled accurate localization of ventricular activation with unknown origin. For 4 patients who underwent epicardial mapping, the median of localization error for the MLR was significantly lower than that for the inverse solution (10.6 vs. 27.3 mm, P = 0.034); a similar result held for 3 patients who underwent endocardial mapping (7.7 vs. 17.1 mm, P = 0.017). The pooled localization error for all epicardial and endocardial sites was also significantly smaller for the MLR compared with the inverse solution (P = 0.005). CONCLUSIONS: The novel pace-mapping approach to localizing the origin of ventricular activation offers an easily implementable supplement and/or alternative to the preprocedure inverse solution; its simplicity makes it suitable for real-time applications during clinical catheter-ablation procedures.

• Klíčová slova
• 12-lead ECG, body surface potential mapping, catheter ablation, pace-mapping, ventricular tachycardia,
• MeSH
• anatomické modely MeSH
• katetrizační ablace metody   MeSH
• komorová tachykardie diagnostické zobrazování   patofyziologie   chirurgie   MeSH
• lidé MeSH
• mapování potenciálů tělesného povrchu přístrojové vybavení   metody   MeSH
• modely kardiovaskulární * MeSH
• zobrazování trojrozměrné přístrojové vybavení   metody   MeSH
• Check Tag
• lidé MeSH
• Publikační typ
• časopisecké články MeSH
• práce podpořená grantem MeSH

In stable ventricular tachycardia (VT), activation mapping and entrainment mapping are the most important strategies to describe the reentrant circuit and its critical components. In many patients, however, VT is noninducible or hemodynamically unstable and unmappable. Several technological advances have broadened ablation options in unmappable VTs. Preprocedural imaging and intraprocedural imaging play an important role in location and extent of the substrate. Electroanatomic mapping with several technological improvements allows more precise electrical assessment of the substrate. A combination of imaging and electroanatomic mapping allows substantial modification of arrhythmogenic substrate in sinus rhythm or during device pacing without hemodynamic compromise.

• Klíčová slova
• Arrhythmia substrate, Cardiac imaging, Catheter ablation, Electroanatomic mapping, Mechanical circulatory support, Ventricular fibrillation, Ventricular tachycardia,
• MeSH
• algoritmy MeSH
• elektrofyziologické techniky kardiologické * MeSH
• elektrokardiografie MeSH
• infarkt myokardu * diagnostické zobrazování   patofyziologie   chirurgie   MeSH
• kardiologické zobrazovací techniky MeSH
• katetrizační ablace * MeSH
• komorová tachykardie * diagnostické zobrazování   patofyziologie   chirurgie   MeSH
• lidé MeSH
• magnetická rezonanční tomografie MeSH
• Check Tag
• lidé MeSH
• Publikační typ
• časopisecké články MeSH
• přehledy MeSH

BACKGROUND: Biventricular pacing (BiV) is employed as the current standard for cardiac resynchronisation therapy. Other pacing modalities have been proposed as alternatives; however, data on changes in electrical activation sequence caused by pacing from various sites are limited. AIM: To describe changes in activation patterns during different ventricular pacing modes in patients with chronic heart failure. METHODS: A total number of 20 patients (mean age 59.6+/-8 years) with chronic heart failure, intraventricular conduction abnormality (QRS >130 ms) or complete AV block were studied. Endocardial activation maps of both ventricles (CARTOTM, Biosense-Webster) were obtained during spontaneous rhythm and biventricular (BiV, n=9), right ventricular bifocal (BiF, n=7) and single-site left ventricular (LV, n=4) pacing. The following parameters were assessed: activation pattern, total LV endocardial activation time (LVAT) and electrical interventricular delay (IVD). RESULTS: Right ventricular apical pacing was associated with the longest LVAT (145+/-24 ms). On the contrary, both BiV and BiF pacing shortened LVAT with BiV being superior in the degree of LVAT reduction (89+/-13 vs 103+/-10 ms, p<0.05). BiV pacing also significantly shortened IVD and modified the LV activation sequence in a complex manner. Such changes were not observed during BiF pacing. In the presence of fusion with spontaneous activation, single-site LV pacing was comparable to BiV pacing. CONCLUSIONS: Among the different pacing modes, BiV pacing and single-site LV pacing with fusion resulted in the most pronounced changes in ventricular activation that appear to be a prerequisite for successful resynchronization of both ventricles.

• MeSH
• dospělí MeSH
• dysfunkce pravé srdeční komory komplikace   patofyziologie   MeSH
• kardiostimulace umělá metody   MeSH
• lidé středního věku MeSH
• lidé MeSH
• senioři MeSH
• srdeční komory anatomie a histologie   patofyziologie   MeSH
• srdeční selhání etiologie   chirurgie   MeSH
• srdeční septum patofyziologie   MeSH
• Check Tag
• dospělí MeSH
• lidé středního věku MeSH
• lidé MeSH
• mužské pohlaví MeSH
• senioři MeSH
• ženské pohlaví MeSH
• Publikační typ
• časopisecké články MeSH

BACKGROUND: The optimal method to identify the arrhythmogenic substrate of scar-related ventricular tachycardia (VT) is unknown. Sites of activation slowing during sinus rhythm (SR) often colocalize with the VT circuit. However, the utility and limitations of such approach for guiding ablation are unknown. METHODS: We conducted a multicenter study in patients with infarct-related VT. The left ventricular (LV) was mapped during activation from 3 directions: SR (or atrial pacing), right ventricular, and LV pacing at 600 ms. Ablation was applied selectively to the cumulative area of slow activation, defined as the sum of all regions with activation times of ≥40 ms per 10 mm. Hemodynamically tolerated VTs were mapped with activation or entrainment. The primary outcome was a composite of appropriate implanted cardioverter-defibrillator therapies and cardiovascular death. RESULTS: In 85 patients, the LV was mapped during activation from 2.4±0.6 directions. The direction of LV activation influenced the location and magnitude of activation slowing. The spatial overlap of activation slowing between SR and right ventricular pacing was 84.2±7.1%, between SR and LV pacing was 61.4±8.8%, and between right ventricular and LV pacing was 71.3±9.6% (P<0.05 between all comparisons). Mapping during SR identified only 66.2±8.2% of the entire area of activation slowing and 58% critical isthmus sites. Activation from other directions by right ventricular and LV stimulation unmasked an additional 33% of slowly conducting zones and 25% critical isthmus sites. The area of maximal activation slowing often corresponded to the site where the wavefront first interacted with the infarct. During a follow-up period of 3.6 years, the primary end point occurred in 14 out of 85 (16.5%) patients. CONCLUSIONS: The spatial distribution of activation slowing is dependent on the direction of LV activation with the area of maximal slowing corresponding to the site where the wavefront first interacts with the infarct. This data may have implications for VT substrate mapping strategies.

• Klíčová slova
• ablation, conduction, isthmus, mapping, reentry, ventricular tachycardia,
• MeSH
• akční potenciály MeSH
• časové faktory MeSH
• elektrofyziologické techniky kardiologické MeSH
• katetrizační ablace * škodlivé účinky   mortalita   MeSH
• komorová tachykardie diagnóza   mortalita   patofyziologie   chirurgie   MeSH
• lidé středního věku MeSH
• lidé MeSH
• prospektivní studie MeSH
• rizikové faktory MeSH
• senioři MeSH
• srdeční frekvence MeSH
• výsledek terapie MeSH
• Check Tag
• lidé středního věku MeSH
• lidé MeSH
• mužské pohlaví MeSH
• senioři MeSH
• ženské pohlaví MeSH
• Publikační typ
• časopisecké články MeSH
• multicentrická studie MeSH
• Research Support, N.I.H., Extramural MeSH
• Geografické názvy
• Evropa MeSH
• Korejská republika MeSH
• Spojené státy americké MeSH

BACKGROUND: The presence and extent of ventricular dyssynchrony are currently assessed from the QRS complex morphology and width. However, similar electrocardiography (ECG) pattern may be caused by variable ventricular activation sequence. This may then contribute to interindividually different response to cardiac resynchronization therapy (CRT). METHODS: Electroanatomical mapping and magnetic resonance imaging scan were performed in 11 patients with left bundle branch block (LBBB, QRS 170 ± 14 ms) and heart failure of ischemic (coronary artery disease (CAD), n = 2) and nonischemic (dilated cardiomyopathy (DCM), n = 9) etiology. Ventricular activation sequence was studied during LBBB and final CRT programming. Presence and extent of scarring were analyzed in the 17-segment left-ventricular (LV) model. RESULTS: Regardless of etiology, presence of typical LBBB was associated with diffuse prolongation of impulse conduction with right-to-left activation sequence. Basal lateral wall was constant site of late activation. This activation pattern was present in "true LBBB," but also in LBBB-like pattern (persistent S wave in V5-6) and left axis deviation. Activation started in right vetricular (RV) apex in patients with left axis deviation at RV free wall in normal axis. Individuals with CAD and DCM patient displayed focal scar. Despite that they exhibited typical LBBB and activation sequence mirrored findings in other LBBB individuals. Reverse remodeling (∆LVESV > 15% after 6 months) was evident in 10 patients. CONCLUSIONS: Both typical LBBB and LBBB-like pattern might be associated with constant activation sequence regardless of etiology and scar localization. Activation initiation in RV apex, not LV activation sequence can be surrogate for left axis deviation. CRT caused inter- and intraventricular LV resynchronization without significantly changed RV activation sequence and duration.

• Klíčová slova
• ECG, biventricular pacing, electroanatomical mapping, left bundle branch block, resynchronization therapy,
• MeSH
• blokáda Tawarova raménka diagnostické zobrazování   patofyziologie   terapie   MeSH
• elektrokardiografie * MeSH
• epikardiální mapování MeSH
• lidé středního věku MeSH
• lidé MeSH
• magnetická rezonanční tomografie MeSH
• senioři MeSH
• srdeční komory diagnostické zobrazování   patofyziologie   MeSH
• srdeční resynchronizační terapie metody   MeSH
• srdeční selhání diagnostické zobrazování   patofyziologie   terapie   MeSH
• Check Tag
• lidé středního věku MeSH
• lidé MeSH
• mužské pohlaví MeSH
• senioři MeSH
• ženské pohlaví MeSH
• Publikační typ
• časopisecké články MeSH

Cardiac resynchronization therapy is a valuable tool to restore left ventricular function in patients experiencing dyssynchronous ventricular activation. However, the non-responder rate is still as high as 40%. Recent studies suggest that left ventricular torsion or specifically the lack thereof might be a good predictor for the response of cardiac resynchronization therapy. Since left ventricular torsion is governed by the muscle fiber orientation and the heterogeneous electromechanical activation of the myocardium, understanding the relation between these components and the ability to measure them is vital. To analyze if locally altered electromechanical activation in heart failure patients affects left ventricular torsion, we conducted a simulation study on 27 personalized left ventricular models. Electroanatomical maps and late gadolinium enhanced magnetic resonance imaging data informed our in-silico model cohort. The angle of rotation was evaluated in every material point of the model and averaged values were used to classify the rotation as clockwise or counterclockwise in each segment and sector of the left ventricle. 88% of the patient models (n = 24) were classified as a wringing rotation and 12% (n = 3) as a rigid-body-type rotation. Comparison to classification based on in vivo rotational NOGA XP maps showed no correlation. Thus, isolated changes of the electromechanical activation sequence in the left ventricle are not sufficient to reproduce the rotation pattern changes observed in vivo and suggest that further patho-mechanisms are involved.

• Klíčová slova
• Lagrangian particle tracking, NOGA XP, cardiac mechanics, electromechanical mapping, finite element simulation, torsion, wringing,
• Publikační typ
• časopisecké články MeSH

BACKGROUND: Left bundle branch pacing (LBBP) is a novel physiological pacing technique which may serve as an alternative to cardiac resynchronization therapy (CRT) by biventricular pacing (BVP). This study assessed ventricular activation patterns and echocardiographic and clinical outcomes of LBBP and compared this to BVP. METHODS: Fifty consecutive patients underwent LBBP or BVP for CRT. Ventricular activation mapping was obtained by ultra-high-frequency ECG (UHF-ECG). Functional and echocardiographic outcomes and hospitalization for heart failure and all-cause mortality after one year from implantation were evaluated. RESULTS: LBBP resulted in greater resynchronization vs BVP (QRS width: 170 ± 16 ms to 128 ± 20 ms vs 174 ± 15 to 144 ± 17 ms, p = 0.002 (LBBP vs BVP); e-DYS 81 ± 17 ms to 0 ± 32 ms vs 77 ± 18 to 16 ± 29 ms, p = 0.016 (LBBP vs BVP)). Improvement in LVEF (from 28 ± 8 to 42 ± 10 percent vs 28 ± 9 to 36 ± 12 percent, LBBP vs BVP, p = 0.078) was similar. Improvement in NYHA function class (from 2.4 to 1.5 and from 2.3 to 1.5 (LBBP vs BVP)), hospitalization for heart failure and all-cause mortality were comparable in both groups. CONCLUSIONS: Ventricular dyssynchrony imaging is an appropriate way to gain a better insight into activation patterns of LBBP and BVP. LBBP resulted in greater resynchronization (e-DYS and QRS duration) with comparable improvement in LVEF, NYHA functional class, hospitalization for heart failure and all-cause mortality at one year of follow up.

• Klíčová slova
• Biventricular pacing, Cardiac resynchronization therapy, Left bundle branch pacing, Ventricular activation mapping,
• Publikační typ
• časopisecké články MeSH

In this report, we dealt with ventricular activation abnormalities in 30 patients with previous non-Q myocardial infarction (MI) by means of the CARDIAG 128.1 device, which enables analysis of ECGs, VCGs and body surface potential maps. The diagnosis was verified by left ventriculography, echocardiography and perfusion scintigraphy. Twenty-nine healthy subjects served as the control group. Morphological findings confirmed the presence of a significant subgroup with serious left ventricular asynergy. Seven electrocardiological variables, which significantly differed from control values, disclosed that non-Q MI is responsible for localized activation time prolongation, and that inferoposterior scars tend to delay the entire activation of ventricles, and to cause disturbances of the terminal depolarization phase together with a decrease in voltage production during QRS. Lesions of the anterior wall and the apicomesial part of the inferoposterior wall affect the distribution of the Q wave more often than the posterior basal ones. The probability of such abnormalities increases with the degree of asynergy. Some VCG criteria increase the sensitivity of electrocardiological analysis. These parameters will be used for evaluating the diagnostic value of electrocardiological analysis in the chronic non-Q MI. Non-Q myocardial infarctions represent a heterogeneous group of infarctions from both electrophysiological and morphological aspects.

• MeSH
• chronická nemoc MeSH
• dospělí MeSH
• echokardiografie MeSH
• elektrokardiografie * MeSH
• funkce levé komory srdeční * MeSH
• infarkt myokardu patofyziologie   MeSH
• ischemická choroba srdeční patofyziologie   MeSH
• lidé středního věku MeSH
• lidé MeSH
• radioisotopová scintigrafie MeSH
• srdce - funkce komor * MeSH
• Check Tag
• dospělí MeSH
• lidé středního věku MeSH
• lidé MeSH
• mužské pohlaví MeSH
• ženské pohlaví MeSH
• Publikační typ
• časopisecké články MeSH
• práce podpořená grantem MeSH
• srovnávací studie MeSH

Cardiac repolarization is prolonged in diabetes mellitus (DM), however the distribution of repolarization durations in diabetic hearts is unknown. We estimated the ventricular repolarization pattern and its relation to the ECG phenomena in diabetic mice. Potential mapping was performed on the anterior ventricular surface in healthy (n=18) and alloxan-induced diabetic (n=12) mice with the 64-electrode array. Activation times, end of repolarization times, and activation-recovery intervals (ARIs) were recorded along with limb lead ECGs. ARIs were shorter in the left as compared to right ventricular leads (P<0.05). The global dispersion of repolarization, interventricular and apicobasal repolarization gradients were greater in DM than in healthy animals (P<0.03). The increased dispersion of repolarization and apicobasal repolarization gradient in DM correlated with the prolonged QTc and Tpeak-Tend intervals, respectively. The increased ventricular repolarization heterogeneity corresponded to the electrocardiographic markers was demonstrated in DM.

• MeSH
• akční potenciály MeSH
• alloxan farmakologie   MeSH
• diabetes mellitus patofyziologie   MeSH
• elektrokardiografie MeSH
• experimentální diabetes mellitus patofyziologie   MeSH
• myši MeSH
• srdce - funkce komor fyziologie   MeSH
• srdeční komory metabolismus   MeSH
• zvířata MeSH
• Check Tag
• mužské pohlaví MeSH
• myši MeSH
• ženské pohlaví MeSH
• zvířata MeSH
• Publikační typ
• časopisecké články MeSH
• práce podpořená grantem MeSH
• Názvy látek
• alloxan MeSH