CRT Implantation Research Articles

Erratum to: Echocardiography and cardiac resynchronization therapy, friends or foes?

Erratum to: Neth Heart J (2016) 24:25–38 DOI 10.1007/s12471-015-0769-3 Figures ​Figures33 and ​and44 and the captions of figures ​figures2,2, ​,3,3, and ​and44 in the original article were incorrect and should have appeared as presented in this erratum. The editors apologise for this oversight and any confusion this may have caused. Fig. 2 Schematic representation of apical rocking and septal flash. Schematic representation of the left ventricle in echocardiographic AP4CH view, showing both septal flash and apical rocking due to LBBB induced mechanical dyssynchrony. a early septal contraction ... Fig. 3 Example of echocardiographic data obtained from a responder to CRT. Apical four chamber view, colour Doppler, septal strain and pulsed-wave Doppler acquisition of a responder to CRT, before, and 6 and 12 months after implantation. Note the continuous ... Fig. 4 Radial strain analysis of parasternal short axis images. Parasternal short axis (PSAX) views and radial strain analysis of a patient with LBBB, imaged prior to CRT implantation. LV lead placement resulted in a mid-posterolateral position (green curve ...

123I-mIBG imaging predicts functional improvement and clinical outcome in patients with heart failure and CRT implantation

I-metaiodobenzylguanidine (mIBG) Echocardiography Myocardial imaging Adrenergic nervous system Cardiac resynchronization therapy (CRT)

Upgrading and replacement in CRT devices: experience counts.

Cardiac resynchronisation therapy has proven to be highly effective in patients with heart failure and an asynchronous contraction pattern of the left ventricle, due to late activation of the posterolateral wall with left bundle branch block configuration on the ECG of more than 150 ms [1]. In pacemaker patients with a high percentage of right ventricular pacing, pacing-induced left ventricular (LV) dysfunction can appear. This newly developing heart failure is most probably the result of pacing-induced LV asynchrony. These patients with pacing-induced heart failure and ICD patients with heart failure who develop a wide QRS complex during follow-up account for the majority of patients who are eligible for an upgrade to a CRT device. In an European survey, up to 25 % of CRT implants were upgrading procedures [2]. The REPLACE registry demonstrated a high percentage of complications in upgrade and revision procedures in 434 CRT patients from 71 centres. It was not stated how many centres actually contributed to this total number of CRT upgrades [3]. Their conclusion ‘pacemaker and implantable cardioverter-defibrillator generator replacements are associated with a notable complication risk, particularly those with lead additions’ made cardiologists somewhat cautious and even reluctant to perform a therapeutic upgrade to CRT. These REPLACE data support careful decision making before device replacement when managing device advisories and when considering upgrades to more complex systems, concluded the authors [3]. And indeed, an upgrade procedure can be complicated and is in need of an experienced skilled operator or at least her or his direct supervision during the procedure. As experience is a major factor in reducing complications during and after device implantation [4], it is reasonable that experience is an even stronger denominator in complicated procedures as primary CRT implants and CRT upgrades. In this issue, the retrospective data of upgrading procedures to CRT devices were compared with the complications in primary CRT implants during the same period [5]. These retrospective data originate from one tertiary centre with a high patient load. Only three experienced operators performed the majority of procedures or supervised them. A: Total number of individual implants of 165 (62 %), including 82 upgrade procedures. Thirty assists of which 16 assists in an upgrade procedure. B: Total number of individual implants of 30 (11 %), including 13 upgrade procedures. Six assists of which 4 assists in an upgrade procedure. C: Total number of individual implants of 18 (7 %), including 9 upgrade procedures. Three assists of which 0 assists in an upgrade procedure. Though these data are retrospective, the complication rate is considerably lower when compared with the literature [3]. The most determining factor in the difference of complication rate is most likely skill, which comes from experience and cooperation during these complicated procedures. It was not investigated whether the determining factor was cooperation or experience or its combination.

Abstract 18347: Patterns of Physical Activity and Survival Following CRT-D Implantation: The ALTITUDE Activity Study

Background: Device-detected physical activity predicts survival following ICD implantation. CRT is implanted in part to improve the functional status of patients with CHF. Patterns of activity changes following CRT implantation, and their relationship to survival, have not been described. Methods: CRT-D patients in the Boston Scientific ALTITUDE registry from 2008-2012 with activity measurements through 210 days were eligible. Remote monitoring data were used to calculate physical activity differences (mean minutes/day) between baseline post-implant (first 3-10d); short-term (30-60 days) and 6 months (180-210 days). The relationship between activity changes between baseline and 6 months by quintile and survival were modeled using Cox regression. Results: Among 36,699 patients (mean age 70.8 + 10.9, 29.5% women), mean activity was 68.9 + 48.9 min/day at baseline, 97.9+ 60.7 min/day at 30-60 days, and 100.0+ 64.9 min/day at 6 months. Mean paired differences between baseline and 6 month activity was 31.1 min/day (95% CI, 30.6-31.6, P<0.0001). However, mean paired differences between 30-60 days and 6 months was only 2.2 min/day (95% CI 1.8-2.5, P<0.0001). Unadjusted survival from 6-months post-CRT-D implant in the highest vs lowest quintile of activity change (baseline - 6 months) was 96.8% vs 83.9% at 1 year, and 87.6% vs 62.1% at 3 years (log-rank P <0.0001 for both comparisons). After adjustment for age, gender, and baseline activity, change in activity at 6 months strongly predicted survival (HR 1.51 per 30 min change, 95% CI 1.48-1.55, two-sided Wald test P <0.0001). Conclusion: This large, nationwide sample of CRT-D recipients suggests that physical activity following implantation increases an average of over 30 min/day, with most of the change manifest in the 2nd month of therapy. Adjusted survival is markedly improved in patients who demonstrate improved activity levels.

IT IS POSSIBLE TO REDUCE EXPOSURE TO IONIZING RADIATION BY > 90% DURING CARDIAC RESYNCHRONIZATION THERAPY IMPLANT PROCEDURES IN THE EP LAB: THE MONTRÉAL HEART INSTITUTE EXPERIENCE WITH LOW-DOSE FLUOROSCOPY SETTINGS AND MEDIGUIDE

All cardiologists working with ionizing radiations (IR) should apply the ALARA (As Low As Reasonably Achievable) principles. Among all procedures, implantation of cardiac resynchronization devices (CRT) result in the highest IR exposure, to the patients, staff and implanter with average IR doses (Dose-Area-Product: DAP) in the range of 2,500 μGray.cm2. These doses can easily double in difficult procedures (longer fluoroscopic times and higher DAP/min generated by fluoroscopic tube angulations, LAO projection being the worst). Our objective is to report on our recent experience to reduce IR exposure with the new 3-D navigation system (MediGuide, MDG, St Jude Inc.) and low-dose fluoroscopy settings during CRT implant procedures. Since January 2013, we’ve collected for all CRT implantations the procedure duration and fluoroscopy exposure (time in minutes, DAP in μGy.cm2 and DAP/min). In June 2013, MDG was installed in one (of 3) EP lab where CRT are implanted and in December 2014, we changed the fluoroscopy settings in all labs to lower-dose parameters (power and frame rate), sacrificing image quality in favor of lower IR exposure. 283 procedures are included in the data base (table). With lower fluoroscopy settings, DAP non-significantly decreased by 33% (P=0.386) compared to normal settings (non-MDG cases). The benefits of lower DAP/min were offset by longer fluoroscopy times. Usage of MDG (normal settings) resulted in 75% reduction of DAP (P<0.001), mainly due to a 72% reduction in fluoro duration (P<0.001). The most striking effects were noted when low-dose fluoroscopy settings were used in combination with MDG: 94% reduction in DAP (vs. NON-MDG), due both to shorter fluoroscopy duration and reduction of DAP/min (all P<0.001). Of note, these beneficial effects were not obtained at the cost of longer procedure duration (expected with lower image quality). It is possible (and desirable) to reduce by >90% ionization radiation exposure during CRT implantation procedures. Adopting low-dose fluoroscopy settings, failed to reduce IR exposure, the benefits from lower DAP/min being offset by longer fluoroscopy usage times. However, using low-fluoroscopy settings with a 3-D navigating system (MediGuide) during the difficult steps (CS cannulation and LV lead placement) significantly reduced exposure to ionizing radiation by 94% (with benefits coming from both lower fluoroscopy time and IR dose/minute).

57 Comparison of Upgraded Versus de-novo Cardiac Resynchronisation Therapy (CRT) Devices on Cardiovascular Outcomes and Response: Abstract 57 Table 1

Background CRT is an effective therapy in HF. Pacemakers and defibrillators are implanted for arrhythmogenic indications. Pacing dependency can induce HF and is an established CRT upgrade criterion [LVEF 40%]. We aimed to compare cardiovascular outcomes between upgraded and de-novo CRT’s. Methodology A retrospective study of all consecutive CRT implants over five years (Jan 2009 – Dec 2013) in a UK tertiary centre. Data was collected on baseline demographics, co-morbidities and indications (NYHA class, ECG, echocardiogram). Comparisons were made for these outcomes: acute response [ 2 mths], all-cause mortality and first hospitalisation. CRT response was defined as >1 NYHA class increase. Results 373 CRT implants were performed (79 upgrades). Upgrade and de-novo patients were matched for all comorbidities. [Table 1][1] demonstrates baseline demographics, indications and CRT response. A Kaplan-Meier analysis was performed on all-cause mortality and time to first hospitalisation, with three year rates demonstrated in the table. A significantly worse long-term response (p 0.002) and all-cause mortality (p 0.043) was demonstrated for upgrade patients. View this table: Abstract 57 Table 1 De-Novo vs. upgrade cardiac resynchronisation therapy device: Demographics, indications, response and outcomes Conclusion Upgraded CRT patients have a worse long-term response and higher all-cause mortality. The potential worse outcome for upgrade patients should be considered before implant. [1]: #T1

Incidence of and risk factors for infectious complications in patients with cardiac device implantation

The use of cardiac implantable electronic device (CIED; pacemakers, implantable cardioverter-defibrillators [ICD], cardiac re-synchronized therapy [CRT]) implantation, one essential treatment for cardiac arrhythmias, is increasing. Infectious complications related to implants are the main reason for device removal and patient morbidity. We sought to identify the incidence of infectious complications among patients with cardiac device implantation and analyze the risk factors for infectious complications. A retrospective analysis was conducted of 1307 patients (61.5±14.2 years-old, 49.6% male) with cardiac device implantation from January 1990 to April 2013. We analyzed the incidence of infectious complications during the follow-up period. To investigate risk factors associated with infectious complications, we conducted a 1:2 matched case-control study of patients with infectious complications and controls without infectious complications who had the same implantation period and physician. Among 1307 patients, 12 had a confirmed device-related infection: 7 with a pocket infection and 5 with infective endocarditis. Over a total of 9091.9 device-years, the incidence of infectious complications was 1.3/1000 device-years, based on the 12 patients with an infection. ICD (5.1/1000 device-year) had a higher incidence of infectious complications than other cardiac devices, and no infectious complications were observed among patients with CRT implantation. Mean duration from the time of implantation to infection was 2.02±1.65 years. In a multivariate analysis, the number of prior procedures including wound revision or scar revision was an independent risk factor for infectious complications (OR=10.88, 95% CI 1.11->999, p=0.040). Infection was a rare complication of cardiac device implantation, but repeated procedures were associated with infectious complications.

ECG myocardial scar quantification predicts reverse left ventricular remodeling and survival after cardiac resynchronization therapy implantation: A retrospective pilot study

IntroductionElectrocardiographic (ECG) LV scar quantification may improve prediction of CRT response. Methods and resultsData were abstracted in 76 patients who underwent a first CRT implantation at 2 US centers. Selvester QRS scar quantification was performed using the LBBB modified QRS scoring method. Seven clinical variables previously associated with reverse LV remodeling (RLVR) and QRS score were included in logistic regression analysis. Survival was compared across QRS score quartiles using Kaplan–Meier curves. RLVR occurred more frequently in patients with QRS score≤5 (63%) than QRS score>5 (22%), (OR=5.83, 95% CI=2.11–16.07). After adjustment for clinical variables using logistic regression, QRS score>5 predicted RLVR (Chi-square=20.3, P=0.005, AUC=0.782). Patients in the lowest quartile of QRS score (<4) had improved survival compared to patients in the other QRS score quartiles (P=0.037). ConclusionECG quantified LV scar predicts RLVR and long-term survival in patients with LBBB undergoing CRT implantation.

9LV lead revision rates have not decreased alongside the improvement in procedural success rates for cardiac resynchronisation therapy

Introduction and Methods: The left ventricular lead required for CRT is challenging to place and can displace requiring revision. We investigated the change in the rates of left ventricular lead procedural success and the rate of subsequent need for LV lead revision over time. A literature search was used to identify all studies reporting success rates of CRT implantation via the Coronary Sinus (CS) route. Studies were ascribed to their year of starting recruitment in order to evaluate temporal trends, which were assessed with linear regression. Follow-up time and LV lead revision rates (expressed as percentage of patients per year) were recorded as a secondary outcome. Results: 155 relevant studies were identified for the full analysis, including 26,488 patients: 75% male, aged 66±11 years, NYHA class 2.8±0.8, LV EF 26±10%, QRS 156±31ms. Within these, 81 studies (13,663 patients, 52% of total) reported lead revision rates over a mean follow up of 8.0 months (range 1-24 months), representing 7798 patient-years of follow-up. Studies following patients for 1-3, 3-6 and 6-12 months reported statistically similar lead revision rates (4.7% p.a., 4.7%, 4.5%), but studies with over 12 months follow up reported more frequent lead revision (6.4%, P<0.001 versus <12m). Failure rates of LV lead placement decreased steadily (−0.5%±0.09% per year, R2 0.18, P for non-zero change <0.001). Lead revision decreased when considered over the whole time period (−0.37%±0.1% per year, R2 0.5, P 0.003). Significant decrease in lead revision rates was seen only before 2000, and there was no significant change after that year (P 0.16). This was not the case for failure to place a lead which continued to decrease significantly (P 0.001). These findings persisted after adjustment of lead displacement rates for follow-up duration. Conclusions: The reported rate of failure to implant an LV lead via the coronary sinus has decreased steadily over the years after the introduction of CRT, likely due to a combination of increasing operator experience and improved lead and delivery system technology. Lead revision rates improved significantly in the initial few years of CRT, but have not apparently changed significantly since about the year 2000. Further development of lead technology and implant techniques should aim to improve lead displacement. ![Graphic][1] Figure 1 Rate of failure to place a left ventricular lead and rate of lead revision. [1]: /embed/inline-graphic-1.gif

MitraClip in CRT non-responders with severe mitral regurgitation

BackgroundSevere mitral regurgitation (MR) ≥3+ and left ventricular dyssynchrony in heart failure patients are markers of CRT non response. The MitraClip (MC) implantation is a therapy for MR ≥3+ in patients with high surgical risk of mitral valve reconstruction. Methods and resultsWe investigated 42 patients with CRT and MR ≥3+ who received an MC device at our center. One and two year mortality rates were compared with the predicted mortality by Seattle Heart Failure Model (SHFM) and meta-analysis global group in chronic heart failure (MAGGIC), using the baseline characteristics of patients at the time of MC implantation.The median time interval between CRT and MC implantation was 20.1 (4.5–43.3) months. In 19 patients we observed a functional regurgitation with normal leaflets and in 23 patients a degenerative mechanism for mitral regurgitation. There was no change in mean QRS duration by biventricular pacing or MC implantation. The use of MC led to significant reductions in: median N-terminal pro-brain natriuretic peptide (NT-proBNP) level (pg/ml) from 3923 to 2636 (p=0.02), tricuspid regurgitation pressure gradient (TRPG) from 43 to 35mmHg (p=0.019) and in left ventricular end-diastolic volume (LVEDV) by MC (p=0.008). At the 2year follow-up interval the all-cause mortality was 25%. ConclusionMC implantation leads to an improvement of NT-proBNP level, TRPG and LVEDV in both functional and degenerative MR but does not influence QRS duration. Two year all-cause mortality was 25% and did not differ significantly from that predicted by SHFM and MAGGIC.

Preventing phrenic nerve stimulation by a patch insulation in an intact swine heart model.

IntroductionPhrenic nerve stimulation (PNS) could be prevented by a silastic patch over the epicardial lead. We studied the effects in preventing PNS by placing a silastic patch directly over an epicardial lead or placing a graft around the phrenic nerve (PN).Methods and ResultsFourteen Lanyu swine were enrolled. A bipolar lead was placed epicardially on the left ventricle (LV) inferior to the PN. An implantable cardioverter-defibrillator (ICD) lead was placed into the right ventricle (RV). The maximal influential distance (MID) was measured under 3 pacing configurations to express the influential electrical field on the PN. The threshold of the LV and PN were evaluated epicardially. Then, PTFE patches of different sizes (10×10 mm, 20×20 mm and 30×30 mm) were placed between the LV lead and PN to study the rise in PN threshold in 7 swine. On the other hand, the PN were surrounded by a PTFE graft of different lengths (10 mm, 20 mm, and 30 mm) in the remaining 7 swine. LV-bipolar pacing showed the shortest MID when compared to the other 2 unipolar pacing configurations at pacing voltage of 10 V. The patch was most effective in preventing PNS during LV-bipolar pacing. PNS was prevented under all circumstances with a larger PTFE patch (30×30 mm) or long graft (30 mm).ConclusionsPNS was avoided by placing a PTFE patch over the LV lead or a graft around the PN despite pacing configurations. Hence if PNS persisted during CRT implantation, a PTFE patch on the LV lead or a graft around the PN could be considered.

Long-Term Performance of Modern Coronary Sinus Leads in Cardiac Resynchronization Therapy

BackgroundCardiac resynchronization therapy (CRT) has become an important pillar of contemporary heart failure therapy. The efficacy of CRT, however, critically relies on proper LV lead placement and performance, which is why data regarding the long-term performance of CS leads are of considerable interest. Available studies are limited by a restricted variety of lead vendors, earlier lead models and / or very short follow-up periods. In the current study, we therefore investigated the long-term performance of modern LV leads in a large “real world” cohort of patients undergoing CRT implantation. Methods and ResultsAll 193 patients who had successfullyundergone CRT implantation at the University Hospital Zurich between September 2003 and January 2010 were included in the study. An overall stable course of stimulation energy was observed over time; neither ischemic etiology, lead configuration, or severely reduced EF had an influence on the evolution of energy thresholds over time. Interestingly, patients with a high energy threshold at baseline experienced a significant reduction during follow-up. In contrast, a significant drop in impedance was seen following implantation, followed by a steady course for the rest of the observation period. Only 15 patients (9.7%) showed an impedance > 1000 Ohm at any time during their follow-up. Seven lead dislocations were observed during follow up. ConclusionsThe current comprehensive analysis of long-term performance of modern coronary sinus leads demonstrates excellent stability, performance and safety. These data may have important implications for physicians involved in biventricular pacemaker implantations and in the follow-up care of these patients.

INCREASE IN QTC DISPERSION PREDICTS ARRHYTHMIC EVENTS IN PATIENTS WITH CARDIAC RESYNCHRONIZATION THERAPY

Aim. Benefits of CRT on mortality and morbidity in patients with severe CHF are clear but the effect of CRT on sudden cardiac death is more controversial. It has been suggested that CRT may catalyze arrhythmogenicity by reversing the normal depolarization pattern. The purpose of this study was to examine the effect of CRT on dispersion of repolarization as assessed by ECG. We also sought to determine the value of dispersion of repolarization ECG parameters in predicting the occurrence of major arrhythmic events (MAE) in follow-up. Material and methods . A total of 48 patients with end-stage heart failure and QRS duration &gt;120 ms underwent CRT. QT dispersion (QTd), T peak t end interval (Tpe) and T peak t end dispersion (Tpe dispersion) were measured before and immediately after CRT implantation. All patients were followed at least 12 months for ventricular tachycardia or fibrillation that were treated with antitachicardia pace or cardioversion. Results. Over 16±7.1 months, 14 patients had a MAE. Compared to baseline, after CRT, QTc dispersion (84.66±37.7 vs 100.36±47.4, p=0.04) and Tpe interval (104.1±20.4 vs 122.03±33, p=0.02) increased significantly. Increase in QTD (ΔQTD) (31.66±39.5 vs 5.57±5.59, p=0.03), and QTc dispersion (ΔQTc dispersion) (40.19±46.6 vs 4.39±14.35, p=0.04) from baseline was signifcantly higher in MAE group. In multiple regression analyses, ΔQTc dispersion predicted MAE (p=0.045, CI: 1.000–1.033). Conclusion. Immediately after CRT implantation QTc dispersion and Tpe interval increases and increase in QTc dispersion predicts MAE in one year follow up.

Left Atrial Volume and the Benefit of Cardiac Resynchronization Therapy in the MADIT-CRT Trial

Left atrial volume (LAV) is an important marker of heart failure (HF) severity. We hypothesized that LAV independently correlates with clinical outcomes in patients who receive cardiac resynchronization therapy with a defibrillator (CRT-D) and can be used for improved risk assessment in this population. The benefit of CRT-D versus defibrillator-only therapy in reducing the risk of HF or death was assessed by LAV (dichotomized at the upper quartile>52 mL/m2) among 1785 patients enrolled in the Multicenter Automatic Defibrillator Implantation Trial with Cardiac Resynchronization Therapy (MADIT-CRT) study. Landmark analysis was used to evaluate the relationship between LAV response to CRT-D and subsequent clinical outcomes. Multivariable analysis showed that patients with a higher baseline LAV experienced 69% (P<0.001) and 59% (P=0.02) increased hazard for HF or death and for all-cause mortality, respectively, independently of baseline left ventricular volume. CRT-D was associated with a significant reduction in LAV compared with defibrillator-only therapy (-28% versus -10%, respectively; P<0.001). Landmark analysis showed that after CRT-D implantation each 1% reduction in LAV was independently associated with a corresponding 4% reduction in the hazard of subsequent HF or death (P<0.001). The assessment of LAV change after CRT implantation improved prediction of clinical response to the device compared with assessment of the corresponding changes in left ventricular volume. LAV is an independent correlate of clinical outcomes in mildly symptomatic HF patients treated with CRT-D. CRT exerts pronounced reverse remodeling effects on the left atrium that independently correlate with improved clinical outcomes after device implantation. URL: http://www.clinicaltrials.gov. Unique identifier: NCT00180271.

Outcome after mitral valve surgery for functional mitral regurgitation in idiopathic dilated cardiomyopathy

Methods We retrospectively investigated 146 patients (131 men, 16 women; mean age, 67 years) with severe functional mitral valve (MV) insufficiency due to dilated cardiomyopathy that were operated on between 2004 till 2012. 35 pts were in New York Heart Association class IV and 102 were in class III. Most of pts had severe enlarged LV (mean end-diastolic size 73.7±7,1ml and volume 293 ±80ml) with depressed systolic function (mean ejection fraction – 26.1±5,6%). Concomitant procedures were tricuspid repair (139 pts) and atrial fibrillation ablation (32 pts). In 35 pts (24%) epicardial LV lead was fixed with subsequent CRT implantation during the same hospitalization. Mitral valve annuloplasty with different types of undersized ring were performed in 101 patients, and 45 had mitral valve replacement (in 6 pts mechanical and in 39 pts biological).

Predictors of functional mitral regurgitation improvement in a short-term observation after cardiac resynchronization therapy

Background: There is little knowledge on predictors of the functional mitral regurgitation (FMR) improvement (FMRI) after CRT implantation in a short-term observation. The role of preserved contractile reserve (CR) in prediction of FMRI is unclear. The study was undertaken to define predictors of FMRI and the impact of FMRI on the reversed remodelling (RR). Methods: This study is subanalysis of the multicenter Myocardial Viability in Cardiac Resynchronization Therapy (VIACRT) trial. Among 90 pts. with ischemic and nonischemic left ventricle dysfunction undergoing CRT therapy, in whom Doppler Echocardiography was performed one day before and 6 weeks after CRT implantation, 66 pts with at least moderate FMR [(grade 2+); mean age 64±10, mean ejection fraction LVEF 25,7%±6, ischemic etiology 48%] were included. The severity of FMR was estimated semiquantitavely from colour-flow Doppler images on a four –point scale. The FMRI was defined as the reduction of the severity for at least one grade. The pts were divided into: gr. A with FMRI (n = 30) and gr. B without FMRI (n=36). Baseline dyssynchrony was defined by TDI. Low-dose dobutamine stress echo (LDSE) was performed before CRT implantation. CR was defined as changes in LVEF > 20% and improvement of segmental contractility. The RR was defined as the reduction of the LV endsystolic volume LVESV >15%. Results: There were no differences concerning the age, gender, etiology (ischemic vs nonischemic), NYHA class and QRS width between both groups. No differences related to ejection fraction, dyssynchrony parameters and site of the latest activation were shown. Multivariate logistic regression analysis revealed the following predictive factors for FMRI: the presence of CR (improved contractility in >3 segments) with an OR = 5.7 (95% CI 1.81-17.97), p=0.005 with sensitivity 65.5% and specificity 72.2%; (AUC = 0.727) and baseline LV diastolic diameter LVDD ≤ 74 mm with an OR = 2.09 , (95% CI 0.75-5.78), p<0.05 , with sensitivity 80.0% and specificity 47.2% (AUC = 0.632). The FMRI was associated with significantly higher reduction of LVESV; gr. A: -38±27 mL vs -12±36 mL in gr. B, p=0.002 and higher increase in LVEF; in gr. A: +10.1±8.5% vs +2.3±5.5% in gr. B p<0.001 respectively. The higher rate of RR in gr. A comparing to gr. B (62.8% vs 37.2%, p<0.001) was noted. Conclusion: Preserved contractile reserve and lesser degree of LV dilation emerged as predictive factors of short-term FMRI after CRT implantation. FMRI is associated with higher rate of response to CRT in term of reverse remodelling.

Optimization of cardiac resynchronization therapy according to the surface ECG

Background: Atrioventricular and interventricular delay (VVD) optimization is an important part of CRT correction. The lack of this procedure or incorrect performance may reduce the positive effect of cardiac resynchronization and enhance Heart Failure (HF). Widely used selection of VVD methods with different ways of echocardiography requires special skills and time-consuming. Aim: To assess the impact of VVD optimization in CRT devices based on changes in the width of the QRS complex using ECG on intracardiac hemodynamic parameters in the long-term period. Materials and methods: 96 patients after CRT implantation were divided into 2 groups (I - with selection of VVD, n=48, II - without selection of VVD, n=48) with sinus rhythm, complete left bundle branch block, ejection fraction (EF) ≤35%.QRS complex was measured before CRT implantation (QRSown), then every 6 months: QRS measurement in the temporary device suppression mode (QRSno-st), measuring the width of the stimulated QRS complex (QRSst) during the VVD optimization process. VVD selection was implemented by gradual change the delay time of stimulation of the right/left ventricle (from 0 to 40 ms) and simultaneous measurement of the stimulated QRS width on ECG. The final VVD result was assumed to the narrowest QRS. Echocardiography was performed in all patients before CRT implantation and then every 6 months. Observation period was 2 years. Results: For 24 month follow-up there was significant reducion in the QRSst width in Group I, p = 0.042. Final values of the QRSst and QRSno-st width were lower in Group I, p = 0.015 and p = 0.001 respectively. There are no significant differences in baseline QRS and QRSst between the groups. End-systolic and end-diastolic LV volume significantly decreased in both groups; reduction in the end-systolic volume was greater in Group I compared to Group II, p = 0.039. EF increased in both groups; percentage increase in EF was significantly higher in Group I, p = 0.048. Functional class (FC) of HF decreased in both groups; the final FC value was significantly lower in Group I, 2.12 versus 2.64 in Group II, p = 0.001. Conclusions: VVD optimization in CRT devices using ECG influences on hemodynamic parameters in the long-term period. The narrowest QRS can be the sign of optimal cardiac synchronization. This safe and reproducible method improves the electrical systole of the myocardium and can adjust the conduction system of ventricles that leads subsequently to a decrease in FC of HF.

The incidence, clinical significance of depression and changes in its clinical course after a cardiac device implantation in patients with congestive heart failure

Purpose: The aim of the study was to assess the incidence, clinical significance of depression and the impact of a cardioverter defibrillator (ICD) or cardiac resynchronization therapy–defibrillator (CRT-D) implantation on the psychiatric status in patients with heart failure (HF). Methods: Prospective, single-center registry encompassed 216 consecutive (HF) patients who were implanted with CRT-D or ICD. The whole population was divided into CRT-Group (n=112; 51.9%) and ICD-Group (n=104; 48.1%). All patients completed the Beck Depression Inventory (BDI-II) and underwent a psychiatric examination at the time of implantation. The assessment of psychiatric status was repeated at 3, 6, 12 months after implantation. Data on long-term follow up were screened to identify patients who developed a composite endpoint defined as death or hospitalization for HF decompensation. Results: Depression was recognized in 52 (46.4%) patients from CRT-Group and in 36 (34.6%) patients from ICD-Group (p=0.078). However the median score in BDI-II at the time of implantation was significantly higher in CRT-Group. The significant reduction in BDI-II score was observed in CRT-Group 6 and 12 months after implantation, whereas in ICD-Group the significant increase was recognized both 6 and 12 months after procedure (Table 1). During median 16.1 months of observation CRT patients with concomitant depression had a significantly higher risk for the development of a composite endpoint than CRT population free of this disorder: 36.5% vs 18.3% (p<0.05). Depression was an independent predictor for a composite endpoint in CRT population (HR 2.2), but not in ICD-Group. The BDI-II score in both groups *p <0.05 vs baseline. BDI-II, Beck Depression Inventory. Conclusions: Depression is a common mental disorder in patients with congestive HF. During long-term follow up a CRT implantation was associated with the significant reduction in the median score in BDI-II, while the significant increase was observed after an ICD implantation. Depression was the independent predictor for a composite endpoint in CRT population, but not in ICD-Group.

Should cardiac resynchronization therapy be considered for patients with severe chronic kidney disease?

Purpose: Chronic kidney disease (CKD) is common in patients with chronic heart failure (CHF) and associated with poor prognosis. Few data are available regarding the benefit of CRT in patients with severe CKD where it may be avoided due to concerns over implant complications. We evaluated whether CRT is safe and beneficial in patients with CKD stage 3b or worse. Methods: Analysis of patients undergoing CRT at 2 centres (2009-11). Patients grouped by estimated glomerular filtration rate (eGFR) ≥45 and <45 ml/min/1.73m2 (CKD class 3b-5). Baseline demographics, complications, change in renal function and outcomes were compared between groups Results: 429 patients were included. Of these 26% had eGFR <45 ml/min/1.73m2 (table). Use of CRT-D was similar between groups. Co-morbidities are common in both groups (overall AF 24%, diabetes 25%, hypertension 44%). Major complication rates were similar between groups; no patients experienced acute renal failure. Both groups exhibited symptomatic benefit: 65% of patients with eGFR≥45 and 71% with eGFR<45 improved by ≥1 NYHA class. The majority of patients had repeat assessment of renal function at 3 months with mean eGFR 60±15 (n=210) in those with eGFR≥45 and 36±12 (n=82) in patients in CKD3b-5. Demographics and outcomes for patients Conclusions: Significant CKD is common in patients undergoing CRT implantation. Whilst 1-yr mortality rates following CRT are greater in those in CKD class 3b-5, a similar improvement in symptom status was seen with no excess of implant related complications. Further evaluation is required to see if CRT may impact on renal function.

Suboptimal heart rate control in heart failure despite optimal medical and device therapy in the real world

Background: Adequate heart rate control is increasingly recognised as an important risk reduction strategy in management of chronic heart failure. We retrospectively analysed our population of heart failure patients undergoing device therapy for adequacy of heart rate control. Methods: Our specialist heart failure nurse-led service oversees treatment initiation, titration and monitoring of patients with heart failure, as per current NICE guidelines. After established medical therapy, eligible patients underwent biventricular pacemaker (CRT) implantation. Data on resting heart rate and rhythm were retrieved and compared before and after device implantation. All continuous data were reported as mean ± standard deviation, categorical data were reported as percentages. SPSS 18 was used for statistical analysis. Results: In the first six months period of 2012, 58 patients underwent CRT implantation (age 68±13 years, female 21%, 84% had ischaemic heart disease or dilated cardiomyopathy, LVEF 25±8%, QRS 154±30ms, 84% had LBBB). Before CRT, majority patients were in sinus rhythm (67%), some (22%) were in atrial fibrillation and minority were paced from the right ventricle apex (11%). On existing medical therapy (55% beta blocker, 65% ACE inhibitor or ARBs, 28% aldosterone blocker, 7% digoxin), baseline heart rate did not differ from heart rate at 6 months after device implantation (68±14 vs. 69±15, p=0.6269). However, after excluding patients with underlying atrial fibrillation at 6 months, 43% patients had HR≥70bpm and would benefit from further heart rate lowering. Conclusions: Our data suggests that a dedicated heart failure specialist team is essential in management of patients with heart failure. Nonetheless despite optimal medical and device therapy in the real world, a large portion of patients had suboptimal heart rate control.