Performance of an active fixation bipolar left ventricular lead vs passive fixation quadripolar leads in cardiac resynchronization therapy, a randomized trial.

BACKGROUND: Usage of active fixation bipolar left ventricular (LV) leads represents an alternative approach to the more commonly used passive fixation quadripolar leads in cardiac resynchronization therapy (CRT). We compared a bipolar LV lead with a side screw for active fixation and passive fixation quadripolar LV leads. METHODS: Sixty-two patients were before CRT implantations randomly allocated to receive a bipolar (n = 31) or quadripolar (n = 31) LV leads. Speckle-tracking radial strain echocardiography was used to define the LV segment with latest mechanical activation as the target LV segment. The electrophysiological measurements and the capability to obtain a proximal position in a coronary vein placed over the target segment were assessed. RESULTS: Upon implantation, the quadripolar lead demonstrated a lower pacing capture threshold than the bipolar lead, but at follow-up, there was no difference. There were no differences in the LV lead implant times or radiation doses. The success rate in reaching the target location was not significantly different between the two LV leads. CONCLUSIONS: The pacing capture thresholds were low, with no significant difference between active fixation bipolar leads and quadripolar leads. Active fixation leads did not promote a more proximal location of the stimulating electrode or a higher grade of concordance to the target segment than passive fixation leads.

Clinical outcome of cardiac resynchronization therapy in patients randomized to an active fixation bipolar left ventricular lead versus a passive quadripolar lead.

Objectives: To compare the clinical outcome of cardiac resynchronization therapy (CRT) in patients receiving a bipolar left ventricular (LV) lead with a side helix for active fixation to the outcome in patients receiving a quadripolar passive fixation LV lead.Design: Sixty-two patients (mean age 72 ± 11 years) were blindly and randomly assigned to the active fixation bipolar lead group (n = 31) or to the quadripolar lead group (n= 31). The LV leads were targeted to the basal LV segment in a vein concordant to the LV segment with the latest mechanical contraction chosen on the basis of preoperative radial strain (RS) echocardiography.Results: At the 6-month follow-up (FU), the reduction in LV end-systolic volume and LV reverse remodelling responder rate, defined as LV end-systolic volume reduction >15%, was 77% in the active fixation group and 83% in the quadripolar group, which was not significantly different. At the 12-month FU, the LV ejection fraction (LVEF) did not differ between the groups. There were no significant differences between the two groups in changes in New York Heart Association (NYHA) functional class or Minnesota Living with Heart Failure Questionnaire score. The occurrence of phrenic nerve stimulation (PNS) was 19% in the active fixation group versus 10% in the quadripolar group (p=.30), and all cases were resolved by reprogramming the device. All patients were alive at the 12-month FU. There was no device infection.Conclusions: There were no significant differences between the active fixation group of patients and the quadripolar group of patients concerning improvement in echocardiographic parameters or clinical symptoms.ClinicalTrials.gov number, NCT04632472.

Impact of Cardiac Implantable Electronic Device Infection: A Clinical and Economic Analysis of the WRAP-IT Trial.

BACKGROUND: Current understanding of the impact of cardiac implantable electronic device (CIED) infection is based on retrospective analyses from medical records or administrative claims data. The WRAP-IT (Worldwide Randomized Antibiotic Envelope Infection Prevention Trial) offers an opportunity to evaluate the clinical and economic impacts of CIED infection from the hospital, payer, and patient perspectives in the US healthcare system. METHODS: This was a prespecified, as-treated analysis evaluating outcomes related to major CIED infections: mortality, quality of life, disruption of CIED therapy, healthcare utilization, and costs. Payer costs were assigned using medicare fee for service national payments, while medicare advantage, hospital, and patient costs were derived from similar hospital admissions in administrative datasets. RESULTS: Major CIED infection was associated with increased all-cause mortality (12-month risk-adjusted hazard ratio, 3.41 [95% CI, 1.81-6.41]; P<0.001), an effect that sustained beyond 12 months (hazard ratio through all follow-up, 2.30 [95% CI, 1.29-4.07]; P=0.004). Quality of life was reduced (P=0.004) and did not normalize for 6 months. Disruptions in CIED therapy were experienced in 36% of infections for a median duration of 184 days. Mean costs were $55 547±$45 802 for the hospital, $26 867±$14 893, for medicare fee for service and $57 978±$29 431 for Medicare Advantage (mean hospital margin of -$30 828±$39 757 for medicare fee for service and -$6055±$45 033 for medicare advantage). Mean out-of-pocket costs for patients were $2156±$1999 for medicare fee for service, and $1658±$1250 for medicare advantage. CONCLUSIONS: This large, prospective analysis corroborates and extends understanding of the impact of CIED infections as seen in real-world datasets. CIED infections severely impact mortality, quality of life, healthcare utilization, and cost in the US healthcare system. Registration: URL: https://www.clinicaltrials.gov Unique Identifier: NCT02277990.

Performance of a novel active fixation quadripolar left ventricular lead for cardiac resynchronization therapy: Attain Stability Quad Clinical Study results.

INTRODUCTION: The Medtronic Attain Stability Quad lead is a quadripolar left ventricular (LV) lead with an active fixation helix assembly designed to fixate the lead within the coronary sinus and pace nonapical regions of the LV. The primary objective of this study was to determine the safety and effectiveness of this novel active fixation quadripolar LV lead. METHODS: Patients with standard indications for cardiac resynchronization therapy (CRT) were enrolled. All patients were followed at 3 and 6 months post-implant and every 6 months thereafter until study closure. Pacing capture thresholds (PCTs) were measured at implant and each follow-up and adverse events (AEs) were recorded upon occurrence. RESULTS: Of the 440 patients who underwent implant procedures, placement of the Attain Stability Quad lead was successful in 426 (96.8%). LV lead-related complications occurred in 10 patients (2.3%), including LV lead dislodgement in three patients (0.7%). The percentage of patients with at least one LV pacing vector with a PCT ≤2.5 V at a 6-month follow-up was 96.3%. The LV lead was successfully fixated to the prespecified pacing location in 97.4% of cases. CONCLUSIONS: This large, multinational study of the Attain Stability Quad lead demonstrated a high rate of implant success with a low complication rate. The active fixation mechanism allowed precise placement of the pacing electrodes at the desired target region with good PCTs and a very low dislodgement rate.

Leadless pacemaker implant in patients with pre-existing infections: Results from the Micra postapproval registry.

INTRODUCTION: Leadless pacemakers may provide a safe and attractive pacing option to patients with cardiac implantable electronic device (CIED) infection. We describe the characteristics and outcomes of patients with a recent CIED infection undergoing Micra implant attempt. METHODS AND RESULTS: Patients with prior CIED infection and device explant with Micra implant within 30 days, were identified from the Micra post approval registry. Procedure characteristics and outcomes were summarized. A total of 105 patients with prior CIED infection underwent Micra implant attempt ≤30 days from prior system explant (84 [80%] pacemakers and 13 [12%] ICD/CRT-D). All system components were explanted in 93% of patients and explant occurred a median of 6 days before Micra implant, with 37% occurring on the day of Micra implant. Micra was successfully implanted in 99% patients, mean follow-up duration was 8.5 ± 7.1 months (range 0-28.5). The majority of patients (91%) received IV antibiotics preimplant, while 42% of patients received IV antibiotics postprocedure. The median length of hospitalization following Micra implant was 2 days (IQR, 1-7). During follow-up, two patients died from sepsis and four patients required system upgrade, of which two patients received Micra to provide temporary pacing support. There were no Micra devices explanted due to infection. CONCLUSION: Implantation of the Micra transcatheter pacemaker is safe and feasible in patients with a recent CIED infection. No recurrent infections that required Micra device removal were seen. Leadless pacemakers appear to be a safe pacing alternative for patients with CIED infection who undergo extraction.

Atrioventricular nodal ablation in patients with resynchronization therapy and atrial fibrillation - long term results.

OBJECTIVES: Atrioventricular nodal ablation (AVNA) is recommended for patients (pts) with cardiac resynchronization therapy (CRT) having atrial fibrillation (AF) and incomplete ventricular capture (Class IIa, level B). AVNA reduces mortality and improves the New York Heart Association (NYHA) functional class during intermediate term follow-up. The objectives were to study the long-term outcome regarding quality of life (QoL) and survival of our CRT pts after AVNA. DESIGN: 37 CRT-pts undergoing AVNA due to inadequate biventricular pacing were included in the study. Data were retrospectively obtained from clinical records and through telephone interviews. RESULTS: Twenty pts died during the follow-up period of average 30.6 ± 24 months. After AVNA the ventricular capture improved significantly from 68.4 ± 23% to 98.5 ± 2% (p < 0.001). A significant and sustained improvement of average 0.3 ± 0.5 (p = 0.001) in NYHA functional class was found. Additionally a large percentage of pts discontinued taking rate reducing drugs with potential severe side effects. CONCLUSION: AVNA in CRT pts was safe and effective. The treatment resulted in a sustained improvement in QoL, including long-term improvement in NYHA functional class.

Active fixation of a thin transvenous left-ventricular lead by a side helix facilitates targeted and stable placement in cardiac resynchronization therapy.

AIMS: Suboptimal placement, phrenic nerve stimulation, and dislodgements of left-ventricular (LV) leads are main challenges in cardiac resynchronization therapy. We investigated the handling, performance, safety, and stability for a novel 4Fr LV lead with a small side helix located proximal to the ring electrode for active fixation of the LV lead. METHODS AND RESULTS: The novel LV lead was successfully implanted in 103 of 106 patients. Patients with dislodged LV leads and with demanding coronary vein anatomies were included. The lead body was rotated clockwise to engage the active fixation side helix in the vein wall. The stimulating electrode was located in basal LV segment and middle LV segment in 54 and 46% of the patients, respectively. The lead was targeted to a vein concordant to the LV segment with latest mechanical activation. Concordant LV lead placement was achieved in 73% of the patients and in adjacent segment in 24%. The average pacing capture threshold (PCT) at implantation was 1.04 ± 0.6 V (n = 103) and at an average follow-up at 7 months, the PCT remained low and no dislodgements have been observed. During follow-up, four leads have been explanted without complications. CONCLUSION: Active fixation of this 4Fr LV lead by using a side helix, offers flexibility to place the lead precisely in targeted vein segments over a wide range of vein anatomies. The average LV pacing threshold was low at implantation and follow-ups. The lead seems to be extractable and no late dislodgements have been observed.

Cardiovascular complications of spinal cord injury.

BACKGROUND: The aim of this paper is to provide an overview of the autonomic innervation of the cardiovascular system and the cardiovascular sequelae of spinal cord injuries. METHOD: A literature search was carried out in the PubMed database, with the search phrases "traumatic spinal cord injury"/"traumatic spinal cord injuries" together with "autonomic dysfunction", "autonomic dysreflexia" and "cardiovascular disease". RESULTS: The most important cardiovascular complications in the acute phase are bradyarrhythmia, hypotension, enhanced vasovagal reflexes, supraventricular/ventricular ectopic beats, vasodilation and venous stasis. Important in the chronic phase are orthostatic hypotension and impaired regulation of blood pressure, blood volume and body temperature. Tetraplegia is frequently accompanied by autonomic dysreflexia, impaired transmission of cardial pain, loss of muscle mass in the left ventricle and pseudoinfarction. Patients with injuries above the sixth thoracic vertebra have a predisposition for autonomic dysreflexia. This is a condition characterised by sudden, uncontrolled sympathetic response accompanied by a rise in blood pressure. Autonomic dysreflexia usually leads to headaches and erythema on the upper chest. The condition may cause cerebral haemorrhage and is potentially life threatening. Patients with spinal cord injuries have an increased risk of atherosclerotic disease due to overweight, lipid disorders, metabolic syndrome and diabetes. They are predisposed to thrombotic emboli due to venous stasis and hypercoagulopathy, particularly immediately after the injury. INTERPRETATION: Knowledge of cardiovascular sequelae after spinal cord injuries and assessment of these is important for correct diagnostics, planning of preventive measures and optimal treatment.

Clinical implication of right ventricular to left ventricular interlead sensed electrical delay in cardiac resynchronization therapy.

AIMS: To evaluate the clinical implication of right ventricular (RV) to left ventricular (LV) interlead sensed electrical delay (RV-LVs) and the relation to ventricular lead position in cardiac resynchronization therapy (CRT). METHODS AND RESULTS: Eighty-five consecutive CRT patients (mean age 66 ± 11 years) received LV lead prospectively targeted to the latest mechanical activated segment (concordant), assessed by two-dimensional speckle tracking radial strain (ST-RS) echocardiography. The RV lead was randomized to RV apex (n= 43) or RV high posterior septum (n= 42). Right ventricular to left ventricular interlead sensed electrical delay was obtained during the CRT implant procedure. Intraventricular dyssynchrony was evaluated by ST-RS echocardiography. Interventricular mechanical delay (IVMD) was measured by using pulse-wave Doppler. Separated by the median RV-LVs (82 ms), a long RV-LVs demonstrated more LV end-systolic volume (LVESV) reduction than a short RV-LVs (-27 ± 20 vs. -16 ± 22%; P= 0.02), 6 months after CRT (6FU). Right ventricular to left ventricular interlead sensed electrical delay correlated to IVMD (r = 0.50; P< 0.001) and intraventricular dyssynchrony (r = 0.25; P= 0.02) at baseline. Concordant LV leads (n= 61) demonstrated superior reduction of LVESV (P= 0.005) 6 months after CRT; however, both RV lead positions had similar effects. Right ventricular to left ventricular interlead sensed electrical delay was irrespective to LV lead concordance and RV lead position (P= ns). Independent predictors to reverse remodelling (reduction of LVESV ≥ 15%) at 6FU were concordant LV lead (odds ratio, 3.210; P= 0.029) and IVMD (odds ratio, 1.028; P= 0.026). CONCLUSION: Right ventricular to left ventricular interlead sensed electrical delay was not predictive to LV reverse remodelling affected by CRT at 6FU. Concordant LV leads demonstrated superior LV reverse remodelling at 6FU. Right ventricular to left ventricular interlead sensed electrical delay was irrespective of ventricular lead position and might be insufficient to target optimal LV lead position in CRT. TRIAL REGISTRATION: http://clinicaltrials.gov. Unique identifier: NCT01035489.

Treatment of cardiogenic shock with left ventricular assist device combined with cardiac resynchronization therapy: a case report.

Cardiogenic shock has a poor prognosis with established treatment strategies. We report a 62 years old man with heart failure exacerbating into refractory cardiogenic shock successfully treated with the combination of a percutaneous left ventricular assist device (LVAD) and subacute cardiac resynchronization therapy (CRT) implantable cardioverter-defibrillator device (CRT-D).

[Cardiac resynchronization therapy in severe congestive heart failure]. / Kardial resynkroniseringsbehandling av alvorlig hjertesvikt.

BACKGROUND: Cardiac resynchronization therapy (CRT) is an established method for treatment of patients with severe congestive heart failure and asynchronous left ventricular contraction. Its clinical and haemodynamic benefits are well documented. We have retrospectively reviewed CRT performed at our centre. MATERIAL AND METHODS: Our department treated 150 patients with CRT according to accepted indications from 1999-2006. The patients were observed for two years and one third reached two-year follow-up. We reviewed operative complications, lead re-implantations, clinical benefits, pacing thresholds, electrogram amplitudes and lead impedance.. RESULTS: There were 20% lead re-implantations after two years of follow-up and a significant improvement in NYHA functional capacity. For the coronary venous lead the average stimulation threshold was stable at 1.2-1.3 V at 0.5 ms, the sensing electrogram amplitude was 10-18 mV and the impedance was 600 ohm at 5.0 V during follow-up. Similar stable electrophysiological values were measured for the right ventricular lead and the atrial lead. INTERPRETATION: There were in general few peroperative complications. All implanted leads in CRT showed stable- and low threshold values during a two-year follow-up period.

Device treatment of atrial tachycardia--minor additional effect of repeating pacing sequences.

PURPOSE: Ramp and burst pacing as treatment for atrial tachycardia (AT), one known trigger mechanism of atrial fibrillation (AF) are available in permanent pacemakers to reduce the burden of AF. An analysis of the success rate of three consecutive antitachycardia pacing sequences is presented. METHOD: The AT 500 (Medtronic) pacemaker was implanted in 36 patients (18 female, mean age 77+/-11 years) with pacemaker indication due to tachybrady arrhythmias (n=34), and other indications (n=2). A standardized AT treatment of 8 sequences of ramp followed by six and four sequences burst pacing was programmed on after 1 month of tachycardia detection only. 5 consecutive sinus beats or 3 min with atrial rhythm not classified as AF or AT defined treatment success and was registered at 3 months follow-up. RESULTS: 2979 episodes (mean 85+/-316) in 17 patients (7 female) were treated and analyzed. The overall treatment success increased from 42+/-27% to 44+/-31% and 45+/-31% during the consecutive ATP sequences (ns). The average ATP success of the first ramp pacing sequences was 95+/-10%, the second ramp ATP sequence was successful in 3+/-6%, and the last ramp ATP sequence in 2+/-5%. CONCLUSION: 95% of the 45% treatment success of a standard AT treatment was achieved by the first ramp pacing sequence. Further antitachycardia pacing sequences did not increase the success rate significantly.

Assessment of regional timing of left ventricular systolic longitudinal movement by Doppler tissue synchronization imaging in structurally normal hearts.

AIMS: To study the feasibility of a new semiautomatic echocardiographic modality called Tissue Synchronization Imaging (TSI) for measurement of the longitudinal left ventricular (LV) movement. METHODS AND RESULTS: TSI was used in 20 subjects with structurally normal hearts to measure the time aspect of the regional longitudinal LV systolic movement in the apical four chamber view. Inter- and intraobserver agreement and the beat to beat variation were tested and compared to previously manually measured peak systolic delay (PSD) between the interventricular septum (IS) and the lateral free wall (LFW) at basal and mid LV, respectively (n=19). TSI showed acceptable reproducibility and close correlation to manually measured PSD. The TSI method did not show false synchronous regional LV movement when synchrony was defined as a PSD<+/-25 ms. After minor adjustment of the TSI interval, 76.9% of the synchronous LV patterns in basal LV were correctly classified as compared to manual measurements. CONCLUSIONS: The TSI method is accurate for clinical screening to reveal synchrony. At the present development the TSI method is not accurate enough to quantify regional systolic LV asynchrony, and still manual measurement of PSD is mandatory.

Reducing atrial tachycardia and atrial fibrillation episodes with a prevention and treatment device and tailored treatment.

BACKGROUND: Pacemaker treatment of known trigger mechanisms for atrial tachyarrhythmias (AT) and atrial fibrillation (AF) has shown reduction in the incidence of AF. A new arrhythmia management device, which included storage of AT/AF (for tailoring treatment) and three prevention algorithms and one for treatment, was examined in order to identify the influence on arrhythmia episodes over a 12-month follow-up (FU) period. METHODS: Twenty-three consecutive patients with known tachybradyarrhythmias were examined. Seven patients had to be excluded (two outliers, four developed permanent AF, one had no detection algorithm turned on at implantation). The remaining 16 patients showed 2723 episodes (675 treated episodes) for evaluation of the effect on episodes/month/patient (e/m/p), treatment success, duration of episodes, circadian distribution and quality of life. RESULTS: The AT/AF e/m/p were reduced from 37 +/- 102 e/m/p at 1-month FU to 16 +/- 48 e/m/p at 3-month FU, 15 +/- 48 e/m/p at 6-month FU and 10 +/- 28 e/m/p at 12-month FU (p < 0.05), according to fewer subjective symptoms. Treatment success remained stable during the observation period (29-40%). Only minor changes in the duration of episodes and the distribution of start times were observed. CONCLUSION: Tailoring treatment by the pacemaker examined with several prevention and treatment algorithms reduces e/m/p and might be a promising supplement in the treatment of selected patients with known AT/AF and bradycardia.

Proportionality of rate response to metabolic workload provided by a rate adaptive pacemaker with automatic rate profile optimization.

OBJECTIVE: The rate response of a pacemaker (PM) was compared with the sinus rate in patients during repeated exercise tests, at different settings of the rate response parameters. METHODS AND RESULTS: In patients with paroxysmal sick sinus syndrome (n=3) or atrioventricular block (n=8), a rate responsive PM was implanted. The activity-dependent pacing rate is represented by the sensor indicated rate (SIR). Each patient performed a treadmill test at 1 month, 1 year, and 2 years after implantation. Prior to the 1 and 2 year tests PM parameters were changed to produce a larger rate increase, especially at moderate levels of daily life activity. During the tests the O(2) consumption and CO(2) production were measured, breath-by-breath, to determine the workload and the anaerobic threshold. On average the workload (oxygen consumption), the patient's sinus rate, and the SIR, showed a linear increase with the workload imposed by the treadmill. In the 1 month and 1 year test the SIR was much lower than the spontaneous rhythm, especially at low or moderate workloads. On the more dynamic setting of several rate adaptive parameters at 2 years, the SIR changed significantly and was close to the spontaneous HR. CONCLUSIONS: The examined PM provides a paced heart rate that is proportional to the workload. For the first time the effect of reprogramming rate response parameters to produce an SIR that is similar to the sinus rate is shown in this study.

Techniques for identification of left ventricular asynchrony for cardiac resynchronization therapy in heart failure.

The most recent treatment option of medically refractory heart failure includes cardiac resynchronization therapy (CRT) by biventricular pacing in selected patients in NYHA functional class III or IV heart failure. The widely used marker to indicate left ventricular (LV) asynchrony has been the surface ECG, but seems not to be a sufficient marker of the mechanical events within the LV and prediction of clinical response. This review presents an overview of techniques for identification of left ventricular intra- and interventricular asynchrony. Both manuscripts for electrical and mechanical asynchrony are reviewed, partly predicting response to CRT. In summary there is still no gold standard for assessment of LV asynchrony for CRT, but both traditional and new echocardiographic methods have shown asynchronous LV contraction in heart failure patients, and resynchronized LV contraction during CRT and should be implemented as additional methods for selecting patients to CRT.

Color Doppler tissue velocity imaging demonstrates significant asynchronous regional left ventricular contraction and relaxation in patients with bundle branch block and heart failure compared with control subjects.

Bundle branch block in patients with severe heart failure (HF) may result in asynchronous regional left ventricular (LV) contraction. Colour Doppler tissue velocity imaging (c-TVI) allows tissue velocity profiles to be measured with a resolution of 10 ms. Normal subjects (n = 30) showed a synchronous regional longitudinal LV pattern of movement, and HF patients with bundle branch block (n = 30) showed asynchronous contraction and relaxation patterns which were quantified by c-TVI as ranging from -22 to 19 ms. This asynchronous LV contraction probably contributes to the deterioration of LV function in HF patients.

Feasibility of color doppler tissue velocity imaging for assessment of regional timing of left ventricular longitudinal movement.

OBJECTIVE--The feasibility of color Doppler tissue velocity imaging (c-TVI) with a high time resolution of 10 ms for simultaneous measurement of the temporal characteristics of regional left ventricular (LV) tissue velocities at different LV sites was examined. Methods and results--In 20 subjects with structurally normal hearts, inter- and intraobserver agreement and the beat-to-beat variation were tested in c-TVI profiles from basal and mid-LV segments of the interventricular septum (IS) and of the lateral free wall (LFW). For peak tissue velocities a mean error of less than 1 cm/s was demonstrated. For systolic regional LV velocity time difference, the mean error was +/- 5 ms, with the best agreement when sampling from basal LV sites. For diastolic regional LV velocity time differences, the mean error was +/- 12 ms. The longitudinal LV movement pattern demonstrated a pattern of incremental tissue velocity from basal to mid-LV, and from IS to LFW sites. Conclusion--The c-TVI method has acceptable inter- and intraobserver agreement and is sufficiently accurate to disclose regional time aspects of LV contraction and relaxation.

Color Doppler tissue velocity imaging can disclose systolic left ventricular asynchrony independent of the QRS morphology in patients with severe heart failure.

UNLABELLED: A QRS width greater than 120 ms is assumed to be a marker of inter- and intraventricular asynchrony in severe heart failure (HF) patients. Color Doppler tissue velocity imaging (c-TVI) with a time resolution of 10 ms was used to study regional left ventricular (LV) longitudinal systolic contraction pattern in HF patients with left and right bundle branch block (LBBB and RBBB) and in patients with normal QRS width. We studied 12 women and 23 men with severe HF, with a mean age of 66 +/- 11 years in New York Heart Association functional Class 2.9 +/- 0.6. Twenty patients had LBBB and 10 of those were accepted for cardiac resynchronization therapy by biventricular pacing (CRT). Ten patients had normal QRS width, and five had RBBB. In the echocardiographic apical four chamber view, regional peak LV tissue velocities and regional LV time differences of peak tissue velocities were compared at basal and mid-LV segments. There were no significant differences in regional mean peak tissue velocities among the patient groups. In patients with LBBB accepted for CRT, the LV lateral free-wall movement at basal LV was 29 ms delayed during main systole, almost significantly different from LBBB patients not accepted for CRT (P = 0.075). Even in HF patients with normal QRS width or RBBB, significant asynchronous longitudinal LV contraction was observed. CONCLUSIONS: For the detection of regional longitudinal LV contraction asynchrony in patients with severe HF, supplementary methods to the surface ECG, such as c-TVI, are strongly recommended.