Prevalence and characteristics of patients with clinical improvement but not significant left ventricular reverse remodeling after cardiac resynchronization therapy

Gated single-photon emission computed tomography myocardial perfusion imaging phase analysis as an imaging biomarker for mortality prediction in heart failure patients undergoing cardiac resynchronization therapy

OBJECTIVE

Cardiac resynchronization therapy (CRT) reduces morbidity and mortality in heart failure patients. The purpose of this study was to assess the value of gated myocardial perfusion single-photon emission computed tomography (GMPS) phase analysis for predicting survival in heart failure patients undergoing CRT.

METHODS

This retrospective cohort study evaluated heart failure patients who underwent GMPS prior to CRT. Phase histogram bandwidth (PHB) and phase SD (PSD) were calculated using GMPS data. Cox proportional hazards model was used to identify independent predictors of overall survival (OS).

RESULTS

A total of 35 patients (age 65.1 ± 13.3, 27 men and 8 women), who were followed for mean of 4.1 ± 2.9 years, were enrolled in the study. PSD of greater than 45° was found to be an independent predictor of poor OS (hazard ratio = 12.63, P = 0.011) when compared with age (hazard ratio = 1.00, P = 0.922), gender (hazard ratio = 0.31, P = 0.155), NYHA class (hazard ratio = 0.45, P = 0.087), QRS duration greater than 150 ms (hazard ratio = 2.38, P = 0.401), pre-CRT left ventricular ejection fraction (LVEF) (hazard ratio = 0.95, P = 0.175) and etiology of heart failure (hazard ratio = 1.42, P = 0.641). Furthermore, PHB greater than 140° was also found to be an independent predictor of poor OS (hazard ratio = 5.63, P = 0.040) when compared with age, gender, NYHA class, QRS duration greater than 150 ms, pre-CRT LVEF and etiology of heart failure.

CONCLUSIONS

PSD and PHB, measured by GMPS, may serve as biomarkers for the prediction of survival in patients undergoing CRT.

Left ventricular remodelling and change in left ventricular global longitudinal strain after cardiac resynchronization therapy: prognostic implications

AIMS

Cardiac resynchronization therapy (CRT) can reduce left ventricular end-systolic volume (LVESV), and a decrease of ≥15% is defined as a response. CRT can also improve LV global longitudinal strain (GLS). Changes in LVESV and LV GLS are individually associated with outcome post-CRT. We investigated LVESV and LV GLS changes and prognostic implications of improvement in LVESV and/or LV GLS, compared with no improvement in either parameter.

METHODS AND RESULTS

Baseline and 6-month echocardiograms were analysed from CRT recipients with heart failure. LV reverse remodelling was defined as a ≥15% reduction in LVESV at 6 months post-CRT. A ≥5% absolute improvement in LV GLS was defined as a change in LV GLS. A total of 1185 patients were included (mean age 65 ± 10 years, 73% male), and those with an improvement in LVESV and LV GLS (n = 131, 11.1%) had significantly lower mortality compared with other groups. On multivariable analysis, an improvement in both LVESV and LV GLS [hazard ratio (HR): 0.47; 95% confidence interval (CI): 0.31-0.71; P < 0.001] or an improvement in either LVESV or LV GLS (HR: 0.57; 95% CI: 0.47-0.71; P < 0.001) were independently associated with better prognosis, compared with no improvement in either parameter.

CONCLUSION

Either a reduction in LVESV and/or an improvement in LV GLS at 6 months post-CRT are independently associated with improved long-term prognosis, compared with no change in both LVESV and LV GLS. This supports the use of LV GLS as a meaningful parameter in defining CRT response.

Combination of left ventricular reverse remodeling and brain natriuretic peptide level at one year after cardiac resynchronization therapy predicts long-term clinical outcome

Introduction

The aim of this study was to investigate the predictors of long-term clinical outcome of heart failure (HF) patients who survived first year after initiation of cardiac resynchronization therapy (CRT).

Methods

This was a single-center observational cohort study of CRT patients implanted because of symptomatic HF with reduced ejection fraction between 2005 and 2013. Left ventricle (LV) diameters and ejection fraction, New York Heart Association (NYHA) class, and level of N-terminal fragment of pro-brain natriuretic peptide (NT-proBNP) were assessed at baseline and 12 months after CRT implantation. Their predictive power for long-term HF hospitalization and mortality, and cardiac and all-cause mortality was investigated.

Results

A total of 315 patients with left bundle branch block or intraventricular conduction delay who survived >1 year after CRT implantation were analyzed in the current study. During a follow-up period of 4.8±2.1 years from CRT implantation, 35.2% patients died from cardiac (19.3%) or non-cardiac (15.9%) causes. Post-CRT LV ejection fraction and LV end-systolic diameter (either 12-month value or the change from baseline) were equally predictive for clinical events. For NT-proBNP, however, the 12-month level was a stronger predictor than the change from baseline. Both reverse LV remodeling and 12-month level of NT-proBNP were independent and comparable predictors of CRT-related clinical outcome, while NT-proBNP response had the strongest association with all-cause mortality. When post-CRT relative change of LV end-systolic diameter and 12-month level of NT-proBNP (dichotomized at -12.3% and 1230 ng/L, respectively) were combined, subgroups of very-high and very-low risk patients were identified.

Conclusion

The level of NT-proBNP and reverse LV remodeling at one year after CRT are independent and complementary predictors of future clinical events. Their combination may help to improve the risk stratification of CRT patients.

What happens to non-responders in cardiac resynchronization therapy?

INTRODUCTION AND OBJECTIVES

Left ventricular reverse remodeling (LVRR) is strongly related to the long-term prognosis of patients undergoing cardiac resynchronization therapy (CRT). The aim of this study was to assess the long-term clinical outcome of patients without LVRR at six months after CRT implantation and to determine the prognostic impact of clinical response in this population.

METHODS

We analyzed 178 consecutive patients who underwent successful CRT device implantation (age 64±11 years; 69% male; 89% in New York Heart Association [NYHA] functional class III; 35% with ischemic cardiomyopathy). Clinical status and echocardiographic parameters were determined before and six months after CRT implantation. We identified those without criteria for LVRR (≥10% increase in left ventricular ejection fraction with ≥15% reduction in left ventricular end-systolic diameter compared to baseline). Clinical responders were defined by a sustained improvement of at least one NYHA functional class.

RESULTS

At six-month assessment after CRT, 109 (61%) patients showed LVRR. During a mean follow-up of 56±21 months, 47 (26%) patients died, with higher mortality in the group without LVRR (36% vs. 20%, p=0.023). Clinical response was greater in patients with LVRR (88% vs. 55%, p<0.001). In patients without LVRR, clinical response to CRT was the strongest independent predictor of survival (hazard ratio: 0.120; 95% confidence interval: 0.039-0.366; p<0.001).

CONCLUSION

Although patients without LVRR six months after CRT implantation had a worse prognosis, with higher all-cause mortality, clinical response can be an independent predictor of survival in this population.

Combined myocardial deformation to predict cardiac resynchronization therapy response in nonischemic cardiomyopathy

BACKGROUND

20-30% of patients do not benefit from cardiac resynchronization therapy (CRT) when the established selection criteria were applied. We hypothesized that a combined assessment of mechanical dyssynchrony, myocardial deformation, and diastolic function would identify patients who would benefit most from CRT.

METHOD

In 36 CRT patients, clinical evaluation and echocardiography were performed before and after CRT. Patients were classified into three subgroups according to their amount of response: echocardiographic responders, clinical responders, and nonresponders. Radial dyssynchrony and left ventricular (LV) global longitudinal, radial, and circumferential peak strain was assessed by speckle-tracking image. Diastolic function was quantified by conventional echocardiography.

RESULT

In addition to left bundle branch block, nonspecific intraventricular conduction disturbance with intraventricular dyssynchrony could also improve LV remodeling. Echocardiographic responders had better global longitudinal strain, global circumferential peak strain, and global radial strain at baseline which significantly increased at 12-month follow-up. An improvement in estimates of LV filling pressure and a decrease in mitral regurgitation and left atrial dimensions were observed only in echocardiographic responders to CRT. Patients with clinical but without echocardiographic response showed a significant improvement in atrioventricular (AV) synchrony and a nonsignificant improvement in other parameters. The nonresponder group did not improve the AV and intraventricular dyssynchrony. CRT could not improve restrictive filling pattern with normal filling time. Overall, those patients with AV and intraventricular dyssynchrony and those with best contractile function and short diastolic filling time of restrictive filling pattern at baseline demonstrated the greatest benefit from CRT.

CONCLUSIONS

Mechanical dyssynchrony, contractile function, and filling pattern are important determinants of the benefits in CRT.

Improvement in left ventricular intrinsic dyssynchrony with cardiac resynchronization therapy

Objective:

Cardiac resynchronization therapy (CRT) has been shown to induce a structural and electrical remodeling; the data on whether left ventricle (LV) reverse remodeling is associated with restitution of intrinsic contraction pattern are unknown. In this study, we investigated the presence of improvement in left ventricular intrinsic dyssynchrony in patients with CRT.

Methods:

A total of 45 CRT recipients were prospectively studied. Dyssynchrony indexes including interventricular mechanical delay (IVMD) and tissue Doppler velocity opposing-wall delay (OWD) as well as QRS duration on 12-lead surface electrocardiogram were recorded before CRT device implantation. After 1 year, patients with chronic biventricular pacing were reprogramed to VVI 40 to allow the resumption of native conduction and contraction pattern. After 4–6 h of intrinsic rhythm, QRS duration and all echocardiographic measurements were recorded. Dyssynchrony was defined as IVMD >40 ms and OWD >65 ms. CRT response was defined by a ≥15% reduction in left ventricular end-systolic volume (LVESV) at a 12-month follow-up.

Results:

Thirty-two patients (71%) showed response to CRT. The native QRS duration reduced significantly from 150±12 ms to 138±14 ms (p<0.001), and dyssynchrony indexes showed a significant improvement only in responders. The mean OWD reduced from 86±37 ms to 50±29 ms (p<0.001), and the mean IVMD decreased from 55±22 ms to 28±22 ms (p<0.001) in responders. The reduction in LVESV was significantly correlated with ΔOWD (r=0.47, p=0.001), ΔIVMD (r=0.45, p=0.001), and ΔQRS (r=0.34, p=0.022).

Conclusion:

Chronic CRT significantly improves LV native contraction pattern and causes reverse remodeling in dyssynchrony.

Sex differences in device therapy for heart failure: utilization, outcomes, and adverse events

BACKGROUND

Multiple studies of heart failure patients demonstrated significant improvement in exercise capacity, quality of life, cardiac left ventricular function, and survival from cardiac resynchronization therapy (CRT), but the underenrollment of women in these studies is notable. Etiological and pathophysiological differences may result in different outcomes in response to this treatment by sex. The observed disproportionate representation of women suggests that many women with heart failure either do not meet current clinical criteria to receive CRT in trials or are not properly recruited and maintained in these studies.

METHODS

We performed a systematic literature review through May 2014 of clinical trials and registries of CRT use that stratified outcomes by sex or reported percent women included. One-hundred eighty-three studies contained sex-specific information.

RESULTS

Ninety percent of the studies evaluated included ≤ 35% women. Fifty-six articles included effectiveness data that reported response with regard to specific outcome parameters. When compared with men, women exhibited more dramatic improvement in specific parameters. In the studies reporting hazard ratios for hospitalization or death, women generally had greater benefit from CRT.

CONCLUSIONS

Our review confirms women are markedly underrepresented in CRT trials, and when a CRT device is implanted, women have a therapeutic response that is equivalent to or better than in men, while there is no difference in adverse events reported by sex.

Association between resolution of fragmented QRS and response to cardiac resynchronization therapy

BACKGROUND

Cardiac resynchronization therapy (CRT) has been recommended for patients with symptomatic heart failure and a wide QRS. Fragmented QRS (fQRS) on a 12-lead electrocardiography (ECG) has been shown to predict cardiac events. We aimed to investigate the relationship between resolution of fQRS and response to CRT.

METHODS

Sixty-seven consecutive patients (38 men, mean age 65 ± 11) with left bundle branch block and fQRS on ECG undergoing CRT were studied. The presence of fQRS was assessed using standardized criteria. Echocardiographic response to CRT was defined by a ≥15% reduction in left ventricular end-systolic volume (LVESV) and resolution of fQRS was defined as decrease in number of leads with fQRS on ECG at 6 months follow-up.

RESULTS

Thirty-nine patients (58%) had response to CRT. LVESV significantly decreased from 150 ± 64 to 100 ± 48 in responders (P = 0.001). There was not any significant decrease in nonresponders (LVESV; from 157 ± 70 to 153 ± 66, P = 0.45). The number of leads with fQRS was decreased from 4.4 ± 1.8 to 1.7 ± 1.6 in responder patients (P < 0.001). The number of leads with fQRS was not significantly changed in nonresponders. (4.2 ± 2.2 vs. 5.1 ± 2.4, P = 0.06). In multivariate analysis, significant associates of response to CRT was evaluated adjusting for etiology of cardiomyopathy, baseline QRS width, left ventricular ejection fraction, number of leads with fQRS and resolution of fQRS. Resolution of fQRS was the only predictor of response to CRT (OR 0.018, 95% CI, 0.004-0.083, P < 0.001).

CONCLUSIONS

After adjusting for potential confounders, resolution of fQRS, is associated with response to CRT.

Predictors of positive response to cardiac resynchronization therapy

BACKGROUND

Approximately 30% of patients treated with cardiac resynchronization therapy (CRT) do not achieve favourable response. The purpose of the present study was to identify echocardiographic and clinical predictors of a positive response to CRT.

METHODS

The study included 82 consecutive heart failure (HF) patients in New York Heart Association (NYHA) functional class III or IV with left bundle branch block (LBBB), QRS duration ≥ 120 ms and left ventricular ejection fraction (LVEF) ≤ 35%. Statistical analysis was performed using IBM SPSS statistical software (SPSS v.21.0 for Mac OS X). A p value < 0.05 was considered statistically significant.

RESULTS

Echocardiographic response was established in 81.6% and clinical response was achieved in 82.9% of patients. Significant univariate predictors of favourable echocardiographic response after 12 months were smaller left ventricular end-diastolic diameter (LVEDD) (odds ratio [OR] 0.89; 95% confidence interval [CI] 0.82 - 0.97, p = 0.01), and smaller left ventricular end-systolic diameter (LVESD) (OR 0.91; 95% CI 0.85 - 0.98, p = 0.01). Lower uric acid concentration was associated with better echocardiographic response (OR 0.99; 95% CI 0.99 - 1.0, p = 0.01). Non-ischemic HF etiology (OR 4.89; 95% CI 1.39 - 17.15, p = 0.01) independently predicted positive clinical response. Multiple stepwise regression analysis demonstrated that LVEDD lower than 75 mm (OR 5.60; 95% confidence interval [CI] 1.36 - 18.61, p = 0.01) was the strongest independent predictor of favourable echocardiographic response.

CONCLUSIONS

Smaller left ventricular end-diastolic and end-systolic diameters and lower serum uric acid concentration were associated with better response to CRT. Left ventricular end-diastolic diameter and non-ischemic heart failure etiology were the strongest independent predictors of positive response to CRT.

Acute echocardiographic optimization of multiple stimulation configurations of cardiac resynchronization therapy through quadripolar left ventricular pacing: a tailored approach

BACKGROUND

Cardiac resynchronization therapy (CRT) is ineffective in approximately 30% of recipients, in part due to sub-optimal left ventricular (LV) pacing location. The Quartet LV lead, with 2 additional electrodes proximal to conventional bipolar lead electrodes, enables 10 different pacing configurations at four independent LV locations. In a CRT patient cohort, we sought to evaluate the spectrum of echocardiographic and electrocardiographic response over these 10 configurations, to select the optimal one in each patient. Moreover, we sought to evaluate the 6-months clinical and echocardiographic response to a "tailored approach" in which the optimal LV pacing configuration for CRT was determined by echocardiographic measures, QRSd and pacing capture thresholds.

METHODS

Twenty-two consecutive CRT indicated patients were implanted with a quadripolar CRT system (St. Jude Medical). Optimal LV pacing configuration was determined by echocardiographic measures, including velocity time integral (VTI), myocardial performance index (MPI) and mitral regurgitation (MR), and an electrocardiographic measure (QRS duration) during pacing from each of the configurations at pre-discharge. The optimal LV pacing vector was chosen for every patient. Clinical and echocardiographic assessment was repeated after 6 months.

RESULTS

Various configurations provided different VTI, MPI, MR and QRSd values. Conventional bipolar vectors (ie, D1-M2, D1-RVc, M2-RVc) were rarely associated with the best echocardiographic improvements and provided significantly worse VTI, MR, MPI, and QRSd values than the best configuration for every patient (P = .005, P = .05 and P = .03 for VTI; P = .01, P = .005 and P = .001 for MPI; P = .003, P = .01 and P = .005 for MR, P > .5, P = .01 and P = .05 for QRSd) Conversely, "unconventional" proximal configurations (ie, making use of P4 and M3 electrodes) were generally characterized by higher acute VTI, MR and MPI improvements. CRT devices were reprogrammed with an "unconventional" LV pacing configuration in 50% of patients. A significant improvement in New York Heart Association class (81%), LV ejection fraction (76%), end-diastolic and end-systolic volumes was observed after 6 months (P = .02, P < .001, P = .02 and P = .003, respectively).

CONCLUSIONS

In this study, conventional bipolar vectors of quadripolar-CRT were rarely associated with the best echocardiographic improvements. Quadripolar CRT utilizing optimal LV pacing configuration was associated with a significant improvement in New York Heart Association class and LV ejection fraction after 6 months.

Effect of cardiac resynchronization therapy on cardiotrophin-1 circulating levels in patients with heart failure

Cardiotrophin-1 (CT-1) is a member of the interleukin (IL-6) family of cytokines. Plasma CT-1 levels correlate with the left ventricle mass index in patients with dilatated cardiomyopathy and congestive heart failure (CHF). The aim of this paper was to evaluate CT-1 plasma levels, before and after cardiac resynchronization therapy CRT, and to characterizeits prognostic role in patients with CHF. Fifty-two consecutive patients (M/F = 39/13; 56 ± 11 years old) underwent clinical and echocardiographic evaluation, and blood sample collection at baseline. The same evaluation was repeated 6.4 ± 0.79 months after CRT. Patients with a decreased LV end-systolic volume by at least 15% (reverse remodeling) were considered echo responders to CRT. Twenty-nine patients (56%) were responders to CRT. After CRT, only 15 patients (29%) showed increased CT-1 after CRT. They were all non responders to CRT. A multivariate, logistic model showed CT-1 as an independent predictor of CRT echo response (p = 0.005; OR 0.97). During follow-up (18 ± 7 months), 21 cardiac events in 18 patients occurred. A Cox multivariable model showed plasma BNP pre-CRT (p = 0.02; CI 1.2-5.6; OR 3.1) and CT1 post-CRT (p = 0.01; CI 1.4-4.3; OR 2.7) as independent predictors of cardiac events. Analysis of CT-1 plasma levels deserves future consideration for larger, longitudinal studies in patients with CHF.

Discrepancy between echocardiographic and patient-reported health status response to cardiac resynchronization therapy: results of the PSYHEART-CRT study

AIMS

The current study examined the degree of agreement between echocardiographic and patient-reported health status response to CRT 6 months after implantation, and evaluated the differences in pre-implantation characteristics of patients with concordant and discordant echocardiographic and health status responses.

METHODS AND RESULTS

Consecutively implanted CRT-defibrillator patients (n = 109, mean age = 65.4 ± 10.1 years, 74 men) were recruited from the University Medical Center Utrecht, The Netherlands. Prior to implantation and 6 months post-implantation, all patients underwent echocardiography and completed the Kansas City Cardiomyopathy Questionnaire (KCCQ). Echocardiographic response was defined as a relative reduction of ≥15% in LV end-systolic volume; an improvement of ≥10 points in KCCQ score indicated a health status response. In the 54 patients with discordant responses, 25 (22.9%) had an echocardiographic response but no health status response and 29 (26.6%) had a health status response but no echocardiographic response. Patients with concordant and discordant responses differed on various pre-implantation characteristics, including sex, employment status, LV volumes, and pre-implantation KCCQ score. In multivariable analysis, pre-implantation KCCQ score [odds ratio (OR) = 0.91, 95% confidence interval (CI) = 0.88-0.95, P < 0.001] and QRS duration (OR = 1.03, 95% CI = 1.01-1.06, P = 0.009) were the only characteristics associated with health status response to CRT.

CONCLUSIONS

Our results show a large discrepancy between echocardiographic and patient-reported health status response to CRT. The most important predictor of health status response was the pre-implantation health status score. These results emphasize that disease-specific health status measures may have additional value over 'objective' measures of CRT response and should be incorporated in clinical practice.

Effect of atrioventricular and ventriculoventricular delay optimization on clinical and echocardiographic outcomes of patients treated with cardiac resynchronization therapy: a meta-analysis

BACKGROUND

Optimization of atrioventricular (AV) and ventriculoventricular (VV) delays of cardiac resynchronization therapy (CRT) devices maximizes left ventricular filling and stroke volume. However, the incremental value of these optimizations over empiric device programming remains unclear. The objective of this analysis was to perform a systematic review and meta-analysis of the effects of AV and VV delay optimization on clinical and echocardiographic end points of patients with heart failure treated with CRT.

METHODS

A standardized search strategy was performed and identified 12 trials comparing AV and/or VV delay optimization and conventional CRT device programming and their effects on various clinical and echocardiographic outcomes. Pooled odds ratios were analyzed using random-effect meta-analysis with Mantel-Haenszel method.

RESULTS

Combined data from a total of 4,356 patients with heart failure treated with CRT showed no differences in clinical or echocardiographic outcomes between patients who underwent AV and/or VV delay optimization and patients who underwent empiric device programming (Mantel-Haenszel odds ratio 0.86 [95% CI 0.68-1.09], P value for overall effect = .21 by intention-to-treat analysis).

CONCLUSION

The current literature suggests that routine AV and/or VV delay optimization has a neutral effect on clinical and echocardiographic outcomes based on pooled data from randomized and nonrandomized studies. Standardization of patient selection and optimization timing and method may help to further define the role of CRT device optimization.

Adrenergic receptor gene polymorphism and left ventricular reverse remodelling after cardiac resynchronization therapy: preliminary results

AIMS

Several factors can influence the extent of left ventricular (LV) reverse remodelling after cardiac resynchronization therapy (CRT) in patients with heart failure (HF). Polymorphism in genes involved in cardiac remodelling, namely beta-adrenergic receptors (ARs), may have a role. We studied the influence of beta-1 Arg389Gly, beta-2 Arg16Gly, and beta-2 Gln27Glu ARs gene polymorphisms on the magnitude of reverse remodelling response to CRT and its possible correlations with the incidence of appropriate implantable cardioverter-defibrillator (ICD) shocks.

METHODS AND RESULTS

Beta-ARs were assessed in 101 patients with HF due to idiopathic (50.5%) or ischaemic (49.5%) dilated cardiomyopathy, undergoing CRT for standard indications [left ventricular ejection fraction (LVEF) 23.5 ± 7.5%, QRS ≥ 120 ms]. Left ventricular ejection fraction was measured by echocardiography at baseline, 6 months after CRT, and periodically afterwards. The LVEF change from baseline was of 3.1 ± 11 units among Gln27Gln, 8.3 ± 10.4 units among Gln27Glu, 11 ± 6.4 units among Glu27Glu carriers (P = 0.018 for Gln27Gln vs. Glu27Glu carriers), and 8.8 ± 9.8 units among Gln27Glu + Glu27Glu carriers (P = 0.006 vs. Gln27Gln). Gln27 homozygotes had a higher incidence of appropriate ICD shocks for fast ventricular tachycardia/ventricular fibrillation.

CONCLUSION

Beta-2 Gln27Glu ARs gene polymorphism may influence LV reverse remodelling after CRT with Glu27Glu carriers showing the greatest improvement. It may also influence the incidence of malignant ventricular tachyarrhythmias.

Neutrophil-to-lymphocyte ratio predicts response to cardiac resynchronization therapy

BACKGROUND

Neutrophil-to-lymphocyte (N/L) ratio has been associated with adverse outcomes in patients with acute coronary syndromes and increased risk for long-term mortality in patients with acute decompensated heart failure. We aimed to investigate the prognostic value of neutrophil-to-lymphocyte ratio on response to cardiac resynchronization therapy (CRT).

MATERIAL AND METHODS

Seventy consecutive patients (mean age 58 ± 13 years; 40 men) undergoing CRT were included in the study. Hematological and echocardiographic parameters were measured before and 6 months after CRT. Echocardiographic response to CRT was defined as a ≥ 15% reduction in left ventricular end-systolic volume at 6-month follow-up.

RESULTS

After 6 months of CRT, 49 (70%) patients were responders. After 6 months, left ventricular ejection fraction (LVEF) had significantly increased, from 21 ± 7% to 34 ± 11% in responder patients (p = 0.001). N/L ratio decreased significantly, from 2.4 ± 1 to 2.1 ± 0.7 in responders (p = 0.04). In multivariate analysis, significant associates of echocardiographic response to CRT was evaluated adjusting for age, etiology of cardiomyopathy, baseline LVEF, New York Heart Association functional class, C-reactive protein, and baseline N/L ratio. Baseline N/L ratio was the only predictor of response to CRT (OR 1.506, 95% CI, 1.011-2.243, p = 0.035).

CONCLUSIONS

N/L ratio at baseline could help to identify patients with response to CRT.

Number of leads with fragmented QRS predicts response to cardiac resynchronization therapy

BACKGROUND

Cardiac resynchronization therapy (CRT) is an effective option in the treatment of patients with heart failure (HF) and wide QRS. Fragmented QRS (fQRS) on 12-lead electrocardiography has been shown to predict cardiac events in several patient populations. However, the relationship between the number of leads with fQRS and response to CRT has not been investigated.

HYPOTHESIS

The number of leads with fQRS may predict response to CRT.

METHODS

One hundred five patients with HF undergoing CRT were prospectively studied. The presence of fQRS was assessed using standardized criteria. Echocardiographic response to CRT was defined by a ≥15% reduction in left ventricular end-systolic volume at 6 months follow-up.

RESULTS

Seventy-four patients (71%) had CRT response after 6 months of follow-up. In multivariate analysis, significant associates of response to CRT were evaluated adjusting for gender, etiology of cardiomyopathy, QRS width, baseline left ventricular ejection fraction, and the number of leads with fQRS. The number of leads with fQRS was the only predictor of response to CRT (odds ratio: 0.61, 95% confidence interval: 0.48-0.77, P < 0.001).

CONCLUSIONS

The more leads with fQRS predicts nonresponse to CRT and may help in the selection of CRT candidates.

Relationship between fragmented QRS and response to cardiac resynchronization therapy

PURPOSE

Cardiac resynchronization therapy (CRT) is an effective treatment for heart failure (HF) with a wide QRS. Fragmented QRS (fQRS) on a 12-lead electrocardiography (ECG) has been shown to predict cardiac events in several patient populations. We aimed to investigate the relationship between fragmented wide QRS (f-wQRS) and left ventricular dyssynchrony and response to CRT.

METHODS

Fifty-three patients with HF undergoing CRT were studied. The presence of fQRS was assessed using standardized criteria. Dyssynchrony was defined as interventricular mechanical delay (IVMD) ≥40 ms and tissue Doppler velocity opposing-wall delay ≥65 ms. Echocardiographic response to CRT was defined by a ≥15 % reduction in left ventricular end-systolic volume at 6 months follow-up.

RESULTS

Fragmented wide QRS was present in 17 (32 %) patients. Interventricular and intraventricular dyssynchrony were highly prevalent in both patient groups with f-wQRS and nonf-wQRS (64.7 % vs 75 %, p = 0.44; 70.6 % vs 72.2 %, p = 0.25). Ischemic HF was significantly higher in patients with f-wQRS than patients with nonf-wQRS (64 % vs 33 %, p = 0.03). Reverse remodeling was developed in 32 (89 %) and 6 (35 %) of patients with nonf-wQRS and f-wQRS, respectively (p = 0.001). In multivariate analysis, significant associates of response to CRT were evaluated adjusting for etiology of cardiomyopathy, QRS width, IVMD, intraventricular delay, and f-wQRS. Lack of f-wQRS was the only predictor of response to CRT (OR 1.556, 95 % CI, 0.016-0.806, p = 0.028).

CONCLUSIONS

Presence of dyssynchrony is necessary but not sufficient to select appropriate candidates for CRT. Presence of f-wQRS on baseline ECG may play a role in identifying patients who may not respond to CRT.

[Three-dimensional imaging in cardiac resynchronization therapy]

Cardiac resynchronization therapy improves clinical symptoms and prognosis of heart failure patients. However, it has been shown that up to 40% of patients do not respond to this therapy. Three main determinants of cardiac resynchronization therapy response have been identified: left ventricular dyssynchrony, left ventricular lead position, and extent and location of myocardial scar tissue. Two-dimensional echocardiography is the first imaging technique to evaluate patients who may be candidates for cardiac resynchronization therapy. However, a multimodality approach based on 3-dimensional imaging techniques may provide a more comprehensive evaluation of these patients by combining the assessment of the aforementioned pathophysiological determinants of cardiac resynchronization therapy response.

Visualization and simulated surgery of the left ventricle in the virtual pathological heart of the Virtual Physiological Human

Ischaemic heart failure remains a significant health and economic problem worldwide. This paper presents a user-friendly software system that will form a part of the virtual pathological heart of the Virtual Physiological Human (VPH2) project, currently being developed under the European Commission Virtual Physiological Human (VPH) programme. VPH2 is an integrated medicine project, which will create a suite of modelling, simulation and visualization tools for patient-specific prediction and planning in cases of post-ischaemic left ventricular dysfunction. The work presented here describes a three-dimensional interactive visualization for simulating left ventricle restoration surgery, comprising the operations of cutting, stitching and patching, and for simulating the elastic deformation of the ventricle to its post-operative shape. This will supply the quantitative measurements required for the post-operative prediction tools being developed in parallel in the same project.