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Objectives: Surgical ventricular reconstruction (SVR) is an effective treatment to improve left ventricular (LV) function in patients with ischaemic heart failure and an LV anterior-apical aneurysm. Ventricular arrhythmia (VA) is an important cause for morbidity and mortality in these patients. Therefore, encircling cryoablation targeting the VA substrate may be required. Programmed electrical stimulation (PES) can identify patients at risk for VA. The objective of this study was to evaluate the incidence and type of VA during long-term follow-up after PES-guided encircling cryoablation concomitant to SVR for primary prevention of VA., Methods: Thirty-eight patients without spontaneous VA referred for SVR who underwent preoperative PES were included (PES group); 27 (71%) patients inducible for aneurysm-related VA received cryoablation. A historical cohort of 39 patients without spontaneous VA, preoperative PES and antiarrhythmic surgery served as the control group. Patients were discharged with an implantable cardioverter defibrillator (ICD)., Results: During 74 ± 35 months of follow-up, no arrhythmic deaths occurred. Five-year survival for the total study population was 78%. Twenty-eight (36%) patients experienced ≥1 VA. There were no differences in the number and type of ICD therapies between groups: shocks, P = 0.699 and antitachypacing, P = 0.403. Five-year VA-free survival was 61% for the PES group and 65% for the control group (hazard ratio 1.67, P = 0.290)., Conclusions: The majority of the patients referred for SVR without previously documented VA was inducible for aneurysm-related VA. During the follow-up, more than one-third of the patients experienced sustained VA and 25% received appropriate ICD therapy. No difference in VA occurrence or ICD therapy was observed between groups.

Background: The relationship between changes in N-terminal pro-brain natriuretic peptide (NT-proBNP) and echocardiographic or clinical definitions of response to cardiac resynchronization therapy (CRT) has not been evaluated. The aims of the present evaluation were to assess: (1) the relationship between changes in NT-proBNP after 6 months of CRT and clinical and echocardiographic responses; (2) the association between NT-proBNP changes and long-term outcome., Methods: In 170 patients treated with CRT (age 61 ± 11 years, 75% male), clinical and echocardiographic parameters and circulating NT-proBNP levels were assessed at baseline and 6 months after CRT. At 6 months follow-up, improvement in New York Heart Association class ≥ 1 point, decrease in left ventricular end-systolic volume ≥ 15%, and decrease in NT-proBNP ≥ 15% defined clinical, echocardiographic, and neurohormonal CRT response, respectively. All-cause mortality data were collected and related to neurohormonal response., Results: Neurohormonal, echocardiographic, and clinical response rates were 54%, 58%, and 66%, respectively. The majority of patients (71%) showing echocardiographic response had NT-proBNP reduction ≥ 15%. In contrast, only 58% of patients who showed clinical response also had NT-proBNP reduction ≥ 15%. During a median follow-up of 32 months, 40 patients died. Patients with neurohormonal response demonstrated a superior long-term outcome compared to patients without neurohormonal response (log-rank P = 0.02)., Conclusions: NT-proBNP reduction ≥ 15% showed better agreement with echocardiographic response compared to clinical response. Neurohormonal response was associated with superior long-term outcome compared to insufficient reduction in NT-proBNP levels., (©2013, The Authors. Journal compilation ©2013 Wiley Periodicals, Inc.)

Background: The mechanism of the beneficial effects of exercise training on autonomic derangement and neurohumoral activation in chronic heart failure (CHF) is largely unexplained. In our here-presented hypothesis-generating study we propose that part of these effects is mediated by the exercise-accompanying somatosensory nerve traffic. To demonstrate this, we compared the effects of periodic electrical somatosensory stimulation in patients with CHF with the effects of exercise training and with usual care., Methods: In a randomized controlled study we measured, in CHF patients, changes in blood pressure, baroreflex sensitivity (BRS), neurohormones, exercise capacity and quality of life (QOL) in response to periodic somatosensory stimulation in the form of 2 Hz transcutaneous electrical nerve stimulation (TENS) at both feet, in response to conventional exercise training (EXTR) and, as control (CTRL), in patients with usual care only., Results: Group sizes were N=31 (TENS group), N=25 (EXTR group) and N=30 (CTRL group), respectively. Practically all improvements in BRS, neurohormone concentrations, exercise capacity and QOL in the TENS group were comparable to, or sometimes even better than in the EXTR group. These improvements were not observed in the CTRL group., Conclusions: This study demonstrates that periodic electrical somatosensory stimulation is as effective as exercise training in improving BRS, neurohormone concentrations, exercise capacity and QOL in CHF patients. These results encourage exploration of exercise modalities that concentrate on rhythm rather than on effort, with the purpose to normalize autonomic derangement and neurohumoral activation in CHF., (Copyright © 2013 Elsevier Ireland Ltd. All rights reserved.)

Implantation of a left ventricular assist device can be challenging in patients with an altered apical anatomy after cardiac surgery or as the result of the presence of a calcified apical aneurysm. In this paper we present 2 cases with a challenging apical anatomy and introduce a new surgical technique facilitating left ventricular assist device implantation in these patients., (Copyright © 2012 The Society of Thoracic Surgeons. Published by Elsevier Inc. All rights reserved.)

Objective: Remodeling of the left ventricle (LV) in ischemic cardiomyopathy frequently leads to functional mitral regurgitation (MR). The indication for correcting MR in patients undergoing LV reconstruction (LVR) is unclear. In this study, we evaluated our strategy of correcting MR≥grade 2+ by restrictive mitral annuloplasty (RMA) during LVR., Methods: We studied 92 consecutive patients (76 men, mean age 61±10 years) who underwent LVR for ischemic heart failure (IHF). RMA was performed in all patients with MR≥grade 2+ on preoperative echocardiography and in patients who showed increased MR to ≥grade 2+ immediately after LVR. Patients were attributed to a RMA and no-RMA group, depending on whether or not concomitant RMA had been performed. Mean clinical and structured echocardiographic follow-up was 47±20 months and was 100% complete., Results: In 38 out of 40 patients (95%) with preoperative MR≥grade 2+, concomitant RMA was planned and performed. In 17 out of 52 patients (33%) with MR

Background: One of the beneficial effects of exercise training in chronic heart failure (CHF) is an improvement in baroreflex sensitivity (BRS), a prognostic index in CHF. In our hypothesis-generating study we propose that at least part of this effect is mediated by neural afferent information, and more specifically, by exercise-induced somatosensory nerve traffic., Objective: To compare the effects of periodic electrical somatosensory stimulation on BRS in patients with CHF with the effects of exercise training and with usual care., Methods: We compared in stable CHF patients the effect of transcutaneous electrical nerve stimulation (TENS, N = 23, LVEF 30 ± 9%) with the effects of bicycle exercise training (EXTR, N = 20, LVEF 32 ± 7%). To mimic exercise-associated somatosensory ergoreceptor stimulation, we applied periodic (2/s, marching pace) burst TENS to both feet. TENS and EXTR sessions were held during two successive days., Results: BRS, measured prior to the first intervention session and one day after the second intervention session, increased by 28% from 3.07 ± 2.06 to 4.24 ± 2.61 ms/mmHg in the TENS group, but did not change in the EXTR group (baseline: 3.37 ± 2.53 ms/mmHg; effect: 3.26 ± 2.54 ms/mmHg) (P(TENS vs EXTR) = 0.02). Heart rate and systolic blood pressure did not change in either group., Conclusions: We demonstrated that periodic somatosensory input alone is sufficient and efficient in increasing BRS in CHF patients. This concept constitutes a basis for studies towards more effective exercise training regimens in the diseased/impaired, in whom training aimed at BRS improvement should possibly focus more on the somatosensory aspect., (Copyright © 2010 Elsevier Ireland Ltd. All rights reserved.)

Objective: Nonischemic dilated cardiomyopathy with functional mitral regurgitation carries a poor prognosis. Mitral valve surgery with implantation of a cardiac support device can treat mitral regurgitation and promote left ventricular reverse remodeling. This observational study evaluates clinical and echocardiographic outcomes of an individualized medico-surgical approach, focusing on mitral regurgitation recurrence and left ventricular reverse remodeling., Methods: Sixty-nine consecutive patients with heart failure (New York Heart Association class III/IV) with functional mitral regurgitation (grade 3+/4+) and left ventricular remodeling (end-diastolic volume 227 ± 73 mL, ejection fraction 26% ± 8%) underwent restrictive mitral annuloplasty (median ring size 26), with (n = 41) or without (n = 28) a cardiac support device and optimal postoperative medical treatment. Patients were clinically and echocardiographically evaluated at up to 3.1 years' median follow-up., Results: Early mortality was 5.8%. Actuarial survival at 1, 2, and 5 years was 86% ± 4%, 79% ± 5%, and 63% ± 7%. New York Heart Association class improved from 3.1 ± 0.4 to 2.0 ± 0.5 (P < .01). Cardiac support device implantation in addition to mitral valve surgery, applied in patients with more advanced left ventricular remodeling, resulted in similar clinical outcome, greater left ventricular end-diastolic volume decrease (33% vs 18%; P = .007), and in a trend toward less recurrent mitral regurgitation of grade 2+ or more (actuarial freedom at 3 years 89% ± 8% vs 63% ± 11%; P = .067)., Conclusions: An individualized medico-surgical approach to nonischemic cardiomyopathy combining restrictive mitral annuloplasty, cardiac support device implantation, and optimal medical management leads to favorable survival and improved functional status, low incidence of significant recurrent mitral regurgitation, and sustained left ventricular reverse remodeling., (Copyright © 2011 The American Association for Thoracic Surgery. Published by Mosby, Inc. All rights reserved.)

Background: Restrictive mitral annuloplasty (RMA) is increasingly applied to treat functional mitral regurgitation in heart failure patients. Previous studies indicated beneficial clinical effects with low recurrence rates. However, the underlying pathophysiology is complex and outcome in terms of left ventricular function is not well known. We investigated chronic effects of RMA on ventricular function in relation to clinical outcome., Methods: Heart failure patients (n = 11) with severe mitral regurgitation scheduled for RMA were analyzed at baseline (presurgery) and midterm follow-up by invasive pressure-volume loops, using conductance catheters. Clinical performance was evaluated by New York Heart Association class, quality-of-life-score, and 6-minute hall-walk-test., Results: All patients were alive without recurrence of mitral regurgitation at follow-up (9.4 ± 4.1 months). Clinical parameters improved significantly (all p < 0.05). Global cardiac function, assessed by cardiac output, stroke volume, and stroke work did not change after RMA. Reverse remodeling was demonstrated by decreased end-systolic and end-diastolic volumes (16% and 11%, both p < 0.001). Systolic function improved, evidenced by increased ejection fraction (0.32 ± 0.05 to 0.36 ± 0.07, p = 0.001) and leftward shift of the end-systolic pressure-volume relation (ESV(100): 116 ± 43 to 74 ± 26 mL, p < 0.001). Diastolic function, however, demonstrated impairment by increased tau (69 ± 13 to 80 ± 14 ms, p < 0.001) and stiffness constant (0.022 ± 0.022 to 0.031 ± 0.028 mL(-1), p = 0.001)., Conclusions: Restrictive mitral annuloplasty significantly improved clinical status without recurrence of mitral regurgitation at midterm follow-up in patients with heart failure. Hemodynamic analyses demonstrated significant reverse remodeling with unchanged global function and improved systolic function, but some signs of diastolic impairment. Overall, RMA appears an appropriate therapy for patients with dilated cardiomyopathy and functional mitral regurgitation., (Copyright © 2010 The Society of Thoracic Surgeons. Published by Elsevier Inc. All rights reserved.)

Objectives: Previous studies demonstrated beneficial short-term effects of surgical ventricular restoration on mechanical dyssynchrony and left ventricular function and improved midterm and long-term clinical parameters. However, long-term effects on systolic and diastolic left ventricular function are still largely unknown., Methods: We studied 9 patients with ischemic dilated cardiomyopathy who underwent surgical ventricular restoration with additional restrictive mitral annuloplasty and/or coronary artery bypass grafting. Invasive hemodynamic measurements by conductance catheter (pressure-volume loops) were obtained before and 6 months after surgery. In addition, New York Heart Association classification, quality-of-life score, and 6-minute hall-walk test were assessed., Results: At 6 months' follow-up, all patients were alive and clinically in improved condition: New York Heart Association class from 3.3 ± 0.5 to 1.4 ± 0.7, quality-of-life score from 46 ± 22 to 15 ± 15, and 6-minute hall-walk test from 302 ± 123 to 444 ± 78 m (all P < .01). Hemodynamic data showed improved cardiac output (4.8 ± 1.4 to 5.6 ± 1.1 L/min), stroke work (6.5 ± 1.9 to 7.1 ± 1.4 mm Hg · L; P = .05), and left ventricular ejection fraction (36% ± 10% to 46% ± 10%; P < .001). Left ventricular surgical remodeling was sustained at 6 months: end-diastolic volume decreased from 246 ± 70 to 180 ± 48 mL and end-systolic volume from 173 ± 77 to 103 ± 40 mL (both P < .001). Left ventricular dyssynchrony decreased from 29% ± 6% to 26% ± 3% (P < .001) and ineffective internal flow fraction decreased from 58% ± 30% to 42% ± 18% (P < .005). Early relaxation (Tau, minimal rate of pressure change) was unchanged, but diastolic stiffness constant increased from 0.012 ± 0.003 to 0.023 ± 0.007 mL(-1) (P < .001)., Conclusions: Surgical ventricular restoration with additional restrictive mitral annuloplasty and/or coronary artery bypass grafting leads to sustained left ventricular volume reduction at 6 months' follow-up. We observed improved systolic function and unchanged early diastolic function but impaired passive diastolic properties. Clinical improvement, supported by decreased New York Heart Association class, improved quality-of-life score, and improved 6-minute hall-walk test may be related to improved systolic function, reduced mechanical dyssynchrony, and reduced wall stress., (Copyright © 2010 The American Association for Thoracic Surgery. Published by Mosby, Inc. All rights reserved.)

Objective: Despite the technical developments in surgical procedures, chronic poststernotomy pain (CPSP) is still very common. Many theories for its cause have been proposed in the literature, but the etiology is still not clear. Pain along the sternal scar and in the upper extremities (sometimes accompanied with paresthesia) persists in about 30% of cases. These symptoms have been regarded as two separate complications. This study investigated all pain symptoms in patients following sternotomy., Design: Retrospective pilot study., Setting: Outpatient clinic at the Leiden University Medical Center., Patients: A cohort of patients who underwent open heart surgery by median sternotomy between January 1, 2004 and January 1, 2006., Interventions: A questionnaire was completed by 631 patients, and a selected sample of 277 patients was examined for pain of the head, neck, back, and chest and upper extremities., Outcome Measures: All pain locations were compared in two groups: 189 patients with sternal pain and 88 patients without sternal pain., Results: We found that pain and muscular tenderness in the investigated areas unrelated to the chest wall incision were significantly more common in patients with sternal pain compared to the nonsternal pain group. No surgical or demographic factors with the exception of female gender were consistent predictors of sternal pain., Conclusion: CPSP is an extensive pain syndrome. Sternal pain is frequently accompanied by pain of the head, neck, back, and upper extremities. Further research on the possible etiology is warranted., (Wiley Periodicals, Inc.)

Objective: Advanced ischemic heart failure can be treated with surgical ventricular restoration (SVR). While numerous risk factors for mortality and recurrent heart failure have been identified, no plain predictor for identifying SVR patients with left ventricular damage beyond recovery is yet available. We tested echocardiographic wall motion score index (WMSI) as a predictor for mortality or poor functional result., Methods: One hundred and one patients electively operated between April 2002 and April 2007 were included for analysis. All patients had advanced ischemic heart failure (NYHA-class>or=III and LVEFor=III) at 1-year follow-up were identified by univariable logistic regression analysis. Preoperatively, a 16-segment echocardiographic WMSI was calculated and receiver operating characteristic curve analysis was used to identify cut-off values for WMSI in predicting poor outcome., Results: Early mortality was 9.9%, late mortality 6.6%. NYHA class improved from 3.2+/-0.4 to 1.5+/-0.7. At 1-year follow-up, 10 patients (12%) were in NYHA class III and the remaining patients were in NYHA class I or II (75 patients, 88%). WMSI was found to be the only statistically significant predictor for poor outcome (odds ratio 139, 95% confidence interval (CI) 17-1116, p<0.0001). The optimal cut-off value for WMSI in predicting mortality or poor functional result was 2.19 with a sensitivity and specificity of 82% (95% CI 81.5-82.5% and 81.4-82.6%). The area under the curve was 0.94 (95% CI 0.90-0.99). Positive and negative predictive values were 67% and 92% respectively (95% CI 66.4-67.6% and 91.4-92.6%)., Conclusions: Sufficient residual remote myocardium is necessary to recover from a SVR procedure and to translate the surgically induced morphological changes into a functional improvement. Preoperative WMSI is a surrogate measure of residual remote myocardial function and is a promising tool for better patient selection to improve results after SVR procedures for advanced ischemic heart failure.

Background: Heart failure patients are increasingly subjected to surgery. Left ventricular (LV) function is generally assessed in awake patients, but intra-operative LV function is not well studied., Aim: To investigate the relation between LV function indices obtained in the catheterization laboratory and those obtained intra-operatively., Methods: We enrolled 11 patients with heart failure (NYHA III-IV) scheduled for surgical interventions. LV function was assessed by pressure-volume loops (conductance catheter) during diagnostic catheterizations and intra-operatively under anaesthetized conditions., Results: Compared to awake conditions, cardiac output was unchanged intra-operatively but ejection fraction was significantly reduced (-16%) due to increased end-diastolic volume (+13%). Systolic and diastolic LV pressure and afterload (E(A)) dropped significantly (-32%, -22%, -35%, respectively). LV systolic function assessed by dP/dt(MAX) and the end-systolic pressure-volume relation (E(ES)) was significantly reduced (-34%, -35%). LV diastolic stiffness was reduced (-44%). Ventricular-arterial coupling (E(A)/E(ES)) was maintained., Conclusion: Intra-operative cardiac output was unchanged compared to awake conditions due to a balance between reduced systolic and improved diastolic function. Ventricular-arterial coupling was maintained by a reduced afterload. Presumably, systolic function and afterload were reduced by anaesthesia, whereas diastolic function improved after pericardectomy. These findings provide insight into the combined effects of anaesthesia, thoracotomy and pericardectomy, and help to interpret LV function measurements in intra-operative conditions.

Background and Aim: The oxygen uptake efficiency slope (OUES) is a novel measure of cardiopulmonary reserve. OUES is measured during an exercise test, but it is independent of the maximally achieved exercise intensity. It has a higher prognostic value in chronic heart failure (CHF) than other exercise test-derived variables such as(Equation is included in full-text article.)or(Equation is included in full-text article.)slope. Exercise training improves(Equation is included in full-text article.)and(Equation is included in full-text article.)in CHF patients. We hypothesized that exercise training also improves OUES., Methods and Results: We studied 34 New York Heart Association (NYHA) class II-III CHF patients who constituted an exercise training group T (N=20; 19 men/1 woman; age 60+/-9 years; left ventricular ejection fraction 34+/-5%) and a control group C (N=14; 13 men/one woman; age 63+/-10 years; left ventricular ejection fraction 34+/-7%). A symptom-limited exercise test was performed at baseline and repeated after 4 weeks (C) or after completion of the training program (T). Exercise training increased NYHA class from 2.6 to 2.0 (P<0.05),(Equation is included in full-text article.)by 14% [P(TvsC)<0.01], and OUES by 19% [P(TvsC)<0.01]. Exercise training decreased(Equation is included in full-text article.)by 14% [P(TvsC)<0.05]., Conclusion: Exercise training improved NYHA class,(Equation is included in full-text article.)and also OUES. This finding is of great potential interest as OUES is insensitive for peak load. Follow-up studies are needed to demonstrate whether OUES improvements induced by exercise training are associated with improved prognosis.

Background: In chronic heart failure (CHF), persistent autonomic derangement and neurohumoral activation cause structural end-organ damage, decrease exercise capacity, and reduce quality of life. Beneficial effects of pharmacotherapy and of exercise training in CHF have been documented at various functional and structural levels. However, pharmacologic treatment can not yet reduce autonomic derangement and neurohumoral activation in CHF to a minimum. Various studies suggest that exercise training is effective in this respect., Methods and Results: After reviewing the available evidence we conclude that exercise training increases baroreflex sensitivity and heart rate variability, and reduces sympathetic outflow, plasma levels of catecholamines, angiotensin II, vasopressin, and brain natriuretic peptides at rest., Conclusions: Exercise training has direct and reflex sympathoinhibitory beneficial effects in CHF. The mechanism by which exercise training normalizes autonomic derangement and neurohumoral activation is to elucidate for further development of CHF-related training programs aimed at maximizing efficacy while minimizing workload.

Background: Treatment of heart failure by advanced surgical procedures such as ventricular restoration (SVR) and restrictive mitral annuloplasty (RMA) is increasingly applied. We studied clinical efficacy of heart failure surgery in patients with severe heart failure., Methods and Results: Thirty-three patients (New York Heart Association (NYHA) class III/IV, left ventricular ejection fraction < or =35%) were included. Patients with moderate to severe mitral regurgitation underwent RMA (85%) and patients with anteroseptal aneurysm underwent SVR (52%). A combined procedure was performed in 12 patients, and additional coronary artery bypass grafting in 27 patients. Clinical and echocardiographic parameters were assessed at baseline and 6 months after surgery. Operative mortality was 3% (n = 1), in-hospital mortality was 9% (n = 3), and there was no late mortality. All clinical parameters were significantly improved at 6 months' follow-up (P < .001); NYHA class improved from 3.4 +/- 0.5 to 1.5 +/- 0.5, Quality-of-life score improved from 44 +/- 22 to 16 +/- 12, and 6-minute walking distance increased from 248 +/- 134 m to 422 +/- 113 m. Left ventricular end-diastolic volume decreased from 107 +/- 32 to 80 +/- 20 mL/m(2) (P < .001) and end-systolic volume decreased from 78 +/- 32 to 53 +/- 15 mL/m(2) (P < .001), whereas ejection fraction improved from 29 +/- 9 to 35 +/- 7% (P < .01)., Conclusions: Surgical treatment of severe heart failure by SVR or RMA was associated with 12% mortality at 6 months. Surviving patients showed highly significant functional and clinical improvements.

Background: Guideline implementation programs for patients with acute myocardial infarction (AMI) enhance adherence to evidence-based medicine (EBM) and improve clinical outcome. Although undertreatment of patients with AMI is well recognized in both acute and chronic phases of care, most implementation programs focus on acute and secondary prevention strategies during the index hospitalization phase only., Hypothesis: Implementation of an all-phase integrated AMI care program maximizes EBM in daily practice and improves the care for patients with AMI., Aim: The objective of this study is to assess the effects of the MISSION! program on adherence to EBM for patients with AMI by the use of performance indicators., Design: The MISSION! protocol is based on the most recent American College of Cardiology/American Heart Association and European Society of Cardiology guidelines for patients with AMI. It contains a prehospital, inhospital, and outpatient clinical framework for decision making and treatment, up to 1 year after the index event. MISSION! concentrates on rapid AMI diagnosis and early reperfusion, followed by active lifestyle improvement and structured medical therapy. Because MISSION! covers both acute and chronic AMI phase, this design implies an intensive multidisciplinary collaboration among all regional health care providers., Conclusion: Continuum of care for patients with AMI is warranted to take full advantage of EBM in day-to-day practice. This manuscript describes the rationale, design, and preliminary results of MISSION!, an all-phase integrated AMI care program.

Background: Acute hemodynamic effects of cardiac resynchronization therapy (CRT) were reported previously, but detailed invasive studies showing hemodynamic consequences of long-term CRT are not available., Methods and Results: We studied 22 patients scheduled for implantation of a CRT device based on conventional criteria (New York Heart Association class III or IV, left ventricular [LV] ejection fraction <35%, left bundle-branch block, and QRS duration >120 ms). During diagnostic catheterization before CRT, we acquired pressure-volume loops using conductance catheters during atrial pacing at 80, 100, 120, and 140 bpm. Studies were repeated during biventricular pacing at the same heart rates after 6 months of CRT. Our data show a significant clinical benefit of CRT (New York Heart Association class change from 3.1+/-0.5 to 2.1+/-0.8; quality-of-life score change from 44+/-12 to 31+/-16; and 6-minute hall-walk distance increased from 260+/-149 to 396+/-129 m; all P<0.001), improved LV ejection fraction (from 29+/-10% to 40+/-13%, P<0.01), decreased end-diastolic pressure (from 18+/-8 to 13+/-6 mm Hg, P<0.05), and reverse remodeling (end-diastolic volume decreased from 257+/-67 to 205+/-54 mL, P<0.01). Previously reported acute improvements in LV function remained present at 6 months: dP/dtmax increased 18%, -dP/dtmin increased 13%, and stroke work increased 34% (all P<0.01). Effects of increased heart rate were improved toward more physiological responses for LV ejection fraction, cardiac output, and dP/dtmax. Moreover, our study showed improved ventricular-arterial coupling (69% increase, P<0.01) and improved mechanical efficiency (44% increase, P<0.01)., Conclusions: Hemodynamic improvements with CRT, previously shown in acute invasive studies, are maintained chronically. In addition, ventricular-arterial coupling, mechanical efficiency, and chronotropic responses are improved after 6 months of CRT. These findings may help to explain the improved functional status and exercise tolerance in patients treated with CRT.

Cardiac resynchronization therapy (CRT) is considered a major advance in the treatment of patients with heart failure. The presence of left ventricular (LV) dyssynchrony seems mandatory for a positive response to CRT. Currently, only patients with wide QRS complexes are considered for CRT, although patients with narrow QRS complexes may also have LV dyssynchrony. In the present study, the incidence of LV dyssynchrony was prospectively evaluated in 64 patients with heart failure and narrow QRS complexes using tissue Doppler imaging.

Introduction: Patients with end-stage heart failure and a wide QRS complex are considered candidates for cardiac resynchronization therapy (CRT). However, 20% to 30% of patients do not respond to CRT. Lack of left ventricular dyssynchrony may explain the nonresponse. Accordingly, we evaluated the presence of left ventricular dyssynchrony using tissue Doppler imaging (TDI) in 90 consecutive patients with heart failure., Methods and Results: Ninety patients with severe heart failure (left ventricular ejection fraction <35%, New York Heart Association class III-IV) were prospectively evaluated. Based on QRS duration, 30 consecutive patients with a narrow QRS complex were included (QRS duration 150 ms). All patients underwent TDI to assess left ventricular dyssynchrony. Extensive left ventricular dyssynchrony was defined as an electromechanical delay on TDI between the septum and lateral wall, the so-called septal-to-lateral delay, of >60 ms. Severe dyssynchrony was observed in 27% of patients with narrow QRS complex, 60% with intermediate QRS duration, and 70% with wide QRS complex. No relation existed between QRS duration and septal-to-lateral delay., Conclusion: From 30% to 40% of heart failure patients with QRS duration >120 ms do not exhibit left ventricular dyssynchrony, which may explain the nonresponse to CRT. Alternatively, 27% of patients with heart failure and a narrow QRS complex show significant left ventricular dyssynchrony and may be candidates for CRT.