Absolute survival after cardiac resynchronization therapy according to baseline QRS duration: a multinational 10-year experience: data from the Multicenter International CRT Study.

BACKGROUND: In the major trials of cardiac resynchronization therapy (CRT), the survival benefit of the therapy, relative to control subjects, increases with QRS duration. In the non-CRT heart failure population, however, a wide QRS duration is associated with a shorter survival. Relative survival benefit from a therapy, however, is not synonymous with a longer absolute survival. We sought to determine whether baseline QRS duration relates to the absolute survival after CRT. METHODS AND RESULTS: In this prospective, longitudinal, observational study, 3,319 consecutive patients undergoing CRT (QRS 120-149 ms 26%, QRS 150-199 ms 58%, and QRS ≥200 ms 16%) were assessed in relation to mortality over 10 years. Overall mortality rates (per 100 patient-years) were 9.2%, 9.3%, and 13.3% in the 3 groups, respectively (all P < .001). Cardiac mortality rates were 6.2, 6.0, and 9.9 per 100 patient-years, respectively (all P < .001). Compared with the QRS 120-149 ms group, cardiac mortality was highest in the QRS ≥200 ms group (hazard ratio [HR] 1.72 [95% CI 1.35-2.19], P < .001), independent of age, gender, New York Heart Association class, presence of atrial fibrillation, heart failure etiology, and left ventricular ejection fraction. Median survival after CRT was longest in patients with a width of QRS 120-149 ms and shortest in patients with a QRS ≥200 ms (P < .001). In multivariable analyses, a QRS ≥200 ms emerged as a powerful independent predictor of both overall (HR 1.44 [95% CI 1.07-1.94], P = .017) and cardiac mortality (HR 1.59 [95% CI 1.14-2.24], P = .007). CONCLUSIONS: At long-term follow-up, absolute overall and cardiac survival after CRT is similar in patients with a preimplant QRS duration of 120 to 149 ms and 150 to 199 ms but markedly shorter in patients with a QRS ≥200 ms.

Rethinking cardiac resynchronization therapy: the impact of ventricular dyssynchrony on outcome.

OBJECTIVE: To analyze whether left ventricular dyssynchrony (LVD) at baseline is predictive for long-term outcome in heart failure (CHF) patients with left ventricular (LV) dysfunction and conduction disturbances treated with cardiac resynchronization therapy (CRT). METHODS: In 535 consecutive individuals with CHF scheduled for implantation of a CRT device, LVD was assessed by tissue Doppler imaging (TDI), defined as an electromechanical delay (EMD) difference of ≥40 ms in 2 opposed left ventricular wall regions (septal vs. lateral, anterior vs. inferior). All-cause mortality, heart transplantation, or assist device implantation was defined as combined primary end point. Secondary end points were measures of reverse LV remodeling and of symptomatic improvement. RESULTS: Mean follow-up was 68 ± 36 [range: 4-150] months. LVD at baseline was present in 308 patients (61%). Of these, 24% reached the combined primary endpoint in contrast to 58% of patients without LVD (p < 0.001). Furthermore, patients with LVD showed pronounced improvement of all secondary end point parameters. In our cohort LVD was an independent predictor for outcome (hazard ratio [95% CI]: 0.30 [0.21-0.42], p < 0.001). CONCLUSIONS: LVD at baseline as assessed by TDI is associated with a more pronounced clinical improvement and is a predictor for transplant-free long-term survival in CRT recipients.

Left ventricular dyssynchrony predicts clinical response to CRT - a long-term follow-up single-center prospective observational cohort study.

BACKGROUND: Until now, there is no consensus regarding the definition of a clinical response to cardiac resynchronization therapy (CRT) in patients with chronic heart failure (CHF) and systolic left ventricular (LV) dysfunction. The aim of this study was to evaluate if echocardiography is predictive for an objective improvement in exercise capacity during long-term follow-up of CRT. METHODS: Each patient underwent echocardiography and spiroergometry both at baseline and at last follow-up. Left ventricular dyssynchrony (LVD) before CRT was defined by tissue Doppler imaging (TDI) as intra-LV delay ≥40 msec (septal-lateral or anterior-posterior). Clinical response to CRT was defined as increase of peakVO2 or as increase of maximal workload >10% as compared to baseline. RESULTS: Mean follow-up was 69 ± 37 months. From the 238 consecutive patients included in the study, 141 (59%) were classified as clinical responders and 97 (41%) as nonresponders. Baseline data of responders and nonresponders were comparable. However, clinical responders showed more often LVD (64%) than nonresponders (42%, P = 0.004). On multivariate regression analysis, nonischemic origin of CHF (ß-coefficient in the final model 0.1, P = 0.04) and LVD at baseline (ß-coefficient in the final model 0.2, P < 0.001) were independently associated with clinical response during long-term follow-up. Patients with LVD at baseline had significant more often an improvement of left ventricular ejection fraction >10% (P = 0.02) and a reduction of left ventricular end-diastolic diameter (LVEDD) >10% (P < 0.01) than patients without LVD at baseline. CONCLUSIONS: LVD at baseline as assessed by a straightforward echocardiographic approach predicts the long-term clinical response to CRT and is associated with a more pronounced reverse LV remodeling.

Cardiac resynchronization therapy in patients with atrial fibrillation: the CERTIFY study (Cardiac Resynchronization Therapy in Atrial Fibrillation Patients Multinational Registry).

OBJECTIVES: The purpose of this study is to determine whether, in patients with atrial fibrillation (AF) undergoing cardiac resynchronization therapy (CRT), atrioventricular junction ablation (AVJA) is associated with a better outcome than treatment with rate-slowing drugs. BACKGROUND: Different trials have demonstrated that CRT is effective in treating heart failure (HF) patients who are in sinus rhythm (SR). No trials have addressed whether CRT confers similar benefits on AF patients, with or without AVJA. METHODS: The clinical outcomes of CRT for patients with permanent AF undergoing CRT combined with either AVJA (n = 443) or rate-slowing drugs (n = 895) were compared with those of SR patients (n = 6,046). RESULTS: Median follow-up was 37 months. Total mortality (6.8 vs. 6.1 per 100 person-years) and cardiac mortality (4.2 vs. 4.0) were similar for patients with AF+AVJA and patients in SR (both p = NS). In contrast, the AF+drugs group had a higher total and cardiac mortality than the SR group and the AF+AVJA group (11.3 and 8.1, respectively; p < 0.001). On multivariable analysis, AF+AVJA had total mortality (hazard ratio [HR]: 0.93, 95% confidence interval [CI]: 0.74 to 1.67) and cardiac mortality (HR: 0.88, 95% CI: 0.66 to 1.17) similar to that of the SR group, independent of known confounders. The AF+drugs group, however, had a higher total mortality (HR: 1.52, 95% CI: 1.26 to 1.82) and cardiac mortality (HR: 1.57, 95% CI: 1.27 to 1.94) than both the SR group and the AF+AVJA group (both p < 0.001). CONCLUSIONS: Long-term survival after CRT among patients with AF+AVJA is similar to that observed among patients in SR. Mortality is higher for AF patients treated with rate-slowing drugs.

Long-term follow-up of cardiac resynchronization therapy: mechanical resynchronization and reverse left ventricular remodeling are predictive for long-term transplant-free survival.

We sought to determine whether correction of mechanical left ventricular (LV) dyssynchrony as defined by tissue Doppler imaging (TDI) is predictive for transplant-free long-term survival in patients (pts.) undergoing cardiac resynchronization therapy (CRT). In 76 CRT recipients TDI curves from the septal, lateral, anterior, and inferior basal LV were obtained at baseline and after 6 ± 4 months. A time difference between regional electromechanical delays (EMD) of ≥40 ms was considered dyssynchronous. At follow-up, pts. were classified as TDI-responders (TDI-R: dyssynchrony at baseline, corrected by CRT) versus non-responders (TDI-NR: either not dyssynchronous at baseline, or persisting dyssynchrony). Pts. were then followed by standard echocardiography over 21 ± 6 months and were re-classified as LV remodelers (LV-R: LV volume reduction of >10%) versus non-remodelers (LV-NR). The end-point during clinical long-term follow-up of 65 ± 38 months was all-cause mortality or heart transplantation. 44 out of the 76 pts. (58%) were classified as TDI-R, 32 (42%) as TDI-NR. Significant reverse LV remodeling was observed in 41 (54%) pts., while 35 (46%) did not improve LV size and function. TDI-R was associated with LV-R in 35 pts. (85%; P < 0.001). During long-term follow-up, 38 pts. (50%) reached the end point, 11 (30%) in the TDI-R group, and 27 (70%) in the TDI-NR group (P < 0.0003). Mechanical resynchronization as defined by TDI translates into a significant survival benefit in CRT recipients.

The potential of multi-slice computed tomography based volumetry for demonstrating reverse remodeling induced by cardiac resynchronization therapy.

BACKGROUND: Multi-slice computed tomography (MSCT) was proved to provide precise cardiac volumetric assessment. Cardiac resynchronization therapy (CRT) is an effective treatment for selected patients with heart failure and reduced ejection fraction (HFREF). In HFREF patients we investigated the potential of MSCT based wall motion analysis in order to demonstrate CRT-induced reversed remodeling. METHODS: Besides six patients with normal cardiac pump function serving as control group seven HFREF patients underwent contrast enhanced MSCT before and after CRT. Short cardiac axis views of the left ventricle (LV) in end-diastole (ED) and end-systole (ES) served for planimetry. Pre- and post-CRT MSCT based volumetry was compared with 2D echo. To demonstrate CRT-induced reverse remodeling, MSCT based multi-segment color-coded polar maps were introduced. RESULTS: With regard to the HFREF patients pre-CRT MSCT based volumetry correlated with 2D echo data for LV-EDV (MSCT 278.3+/-75.0mL vs. echo 274.4+/-85.6mL) r=0.380, p=0.401, LV-ESV (MSCT 226.7+/-75.4mL vs. echo 220.1+/-74.0mL) r=0.323, p=0.479 and LV-EF (MSCT 20.2+/-8.8% vs. echo 20.0+/-11.9%) r=0.617, p=0.143. Post-CRT MSCT correlated well with 2D echo: LV-EDV (MSCT 218.9+/-106.4mL vs. echo 188.7+/-93.1mL) r=0.87, p=0.011, LV-ESV (MSCT 145+/-71.5mL vs. echo 125.6+/-78mL) r=0.84, p=0.018 and LV-EF (MSCT 29.6+/-11.3mL vs. echo 38.6+/-14.6mL) r=0.89, p=0.007. There was a significant increase of the mid-ventricular septum in terms of absolute LV wall thickening of the responders (pre 0.9+/-2.1mm vs. post 3.3+/-2.2mm; p<0.0005). CONCLUSION: MSCT based volumetry involving multi-segment color-coded polar maps offers wall motion analysis to demonstrate CRT-induced reverse remodeling which needs to be further validated.

Mitral regurgitation--evaluation of a multidimensional echocardiographic grading system. A study on 177 patients with chronic primary and secondary mitral regurgitation.

INTRODUCTION: In grading mitral regurgitation (MR) magnetic resonance imaging is the gold standard but 2D echo is mostly used in clinical practice. However, each single echo parameter is prone to confounding influences. With regard to chronic primary and secondary MR the purpose of this study was to compare a new multi-dimensional echo-based grading system with an independent pre-operatively used invasive standard. METHODS: In a retrospective study we analyzed 177 patients with different degrees of MR severity, who were examined both by echocardiography and by cardiac catheterization. For MR grading a combination of four echocardiographic parameters was used: density of the regurgitation velocity profile, peak mitral inflow velocity (Vmax E-wave), radius of the proximal flow convergence zone (PISA), and vena contracta (Vc) width. Invasive grading was based on left ventriculography (Seller's method), V wave hight, and regurgitation fraction. Both methods resulted in an integrative score on an eight point scale (

Low night-to-night variability of sleep disordered breathing in patients with stable congestive heart failure.

Sleep disordered breathing (SDB) has a high prevalence and prognostic impact in patients with chronic heart failure (CHF). Aim of this study was to investigate variability of SDB parameters in patients with stable CHF. Cardiorespiratory polygraphy was used to determine SDB in two consecutive nights in 50 CHF patients (NYHA class > or = II, LV-EF < or = 40%). The apnea-hypopnea-index (AHI) and apnoea-index (AI) were used to quantify SDB severity. Central, obstructive or mixed SDB were classified according to the majority of events. There was an excellent correlation in AHI (r = 0.948, P < 0.001) and AI (r = 0.842, P < 0.001) results of both nights. The overall number of detected apnea and hypopnea during the first night as compared to the maximum of both nights was 85% for the AHI and 77% for the AI. The reproducibility was dependent on SDB severity: AHI 15-29/h = 87%, AHI > or = 30/h = 92% and AI > or = 10/h = 83%. Classification was identical in 17 out of 19 patients with AI > or = 10/h. In patients with stable CHF a single night of cardiorespiratory monitoring leads to representative results on severity and type of SDB. This may enhance the applicability and dissemination of cardiorespiratory polygraphy in clinical practice.

Adaptive servoventilation improves cardiac function in patients with chronic heart failure and Cheyne-Stokes respiration.

BACKGROUND AND AIMS: Sleep disordered breathing (SDB), especially Cheyne-Stokes respiration (CSR) is common in patients with chronic heart failure (CHF). Adaptive servoventilation (ASV) was recently introduced to treat CSR in CHF. The aim of this study was to investigate the effects of ASV on CSR and CHF parameters. METHODS: In 29 male patients (63.9+/-9 years, NYHA> or =II, left ventricular ejection fraction [LV-EF]< or =40%), cardiorespiratory polygraphy, cardiopulmonary exercise (CPX) testing, and echocardiography were performed and concentrations of NT-proBNP determined before and after 5.8+/-3.5 months (median 5.7 months) of ASV (AutoSet CS2, ResMed) treatment. All patients also received guideline-driven CHF therapy. RESULTS: Apnoea-hypopnoea-index was reduced from 37.4+/-9.4/h to 3.9+/-4.1/h (p<0.001). Workload during CPX testing increased from 81+/-26 to 100+/-31 W (p=0.005), oxygen uptake (VO2) at the anaerobic threshold from 12.6+/-3 to 15.3+/-4 ml/kg/min (p=0.01) and predicted peak VO2 from 58+/-12% to 69+/-17% (p=0.007). LV-EF increased from 28.2+/-7% to 35.2+/-11% (p=0.001), and NT-proBNP levels decreased significantly (2285+/-2192 pg/ml to 1061+/-1293 pg/ml, p=0.01). CONCLUSIONS: In selected patients with CHF and CSR, addition of ASV to standard heart failure therapy is able to improve SDB, CPX test results, LV-EF and NT-proBNP concentrations.

Long-term survival in patients undergoing cardiac resynchronization therapy: the importance of performing atrio-ventricular junction ablation in patients with permanent atrial fibrillation.

AIMS: To investigate the effects of cardiac resynchronization therapy (CRT) on survival in heart failure (HF) patients with permanent atrial fibrillation (AF) and the role of atrio-ventricular junction (AVJ) ablation in these patients. METHODS AND RESULTS: Data from 1285 consecutive patients implanted with CRT devices are presented: 1042 patients were in sinus rhythm (SR) and 243 (19%) in AF. Rate control in AF was achieved by either ablating the AVJ in 118 patients (AVJ-abl) or prescribing negative chronotropic drugs (AF-Drugs). Compared with SR, patients with AF were significantly older, more likely to be non-ischaemic, with higher ejection fraction, shorter QRS duration, and less often received ICD back-up. During a median follow-up of 34 months, 170/1042 patients in SR and 39/243 in AF died (mortality: 8.4 and 8.9 per 100 person-year, respectively). Adjusted hazard ratios were similar for all-cause and cardiac mortality [0.9 (0.57-1.42), P = 0.64 and 1.00 (0.60-1.66) P = 0.99, respectively]. Among AF patients, only 11/118 AVJ-abl patients died vs. 28/125 AF-Drugs patients (mortality: 4.3 and 15.2 per 100 person-year, respectively, P < 0.001). Adjusted hazard ratios of AVJ-abl vs. AF-Drugs was 0.26 [95% confidence interval (CI) 0.09-0.73, P = 0.010] for all-cause mortality, 0.31 (95% CI 0.10-0.99, P = 0.048) for cardiac mortality, and 0.15 (95% CI 0.03-0.70, P = 0.016) for HF mortality. CONCLUSION: Patients with HF and AF treated with CRT have similar mortality compared with patients in SR. In AF, AVJ ablation in addition to CRT significantly improves overall survival compared with CRT alone, primarily by reducing HF death.

Influence of cardiac resynchronisation therapy on different types of sleep disordered breathing.

AIMS: This study investigates the influence of cardiac resynchronisation therapy (CRT) on sleep disordered breathing (SDB) in patients with severe heart failure (HF). METHODS AND RESULTS: Seventy-seven patients with HF (19 females; 62.6+/-10 years) eligible for CRT were screened for presence, type, and severity of SDB before and after CRT initiation (5.3+/-3 months) using cardiorespiratory polygraphy. NYHA class, frequency of nycturia, cardiopulmonary exercise, 6-minute walking test results, and echocardiography parameters were obtained at baseline and follow-up. Central sleep apnoea (CSA) was documented in 36 (47%), obstructive sleep apnoea (OSA) in 26 (34%), and no SDB in 15 (19%) patients. CRT improved clinical and haemodynamic parameters. SDB parameters improved in CSA patients only (apnoea hypopnoea index: 31.2+/-15.5 to 17.3+/-13.7/h, p<0.001; SaO2min: 81.8+/-6.6 to 84.8+/-3.3%, p=0.02, desaturation: 6.5+/-2.3 to 5.5+/-0.8%, p=0.004). Daytime capillary pCO2 was significantly lower in CSA patients compared to those without SDB with a trend towards increase with CRT (35.5+/-4.2 to 37.9+/-5.7 mm Hg, ns). After classifying short term clinical and haemodynamic CRT effects, improved SDB parameters in CSA occurred in responders only. CONCLUSIONS: In patients with severe HF eligible for CRT, CSA is common and can be influenced by CRT, this improvement depends on good clinical and haemodynamic response to CRT.

Clinical utility of intrathoracic impedance monitoring to alert patients with an implanted device of deteriorating chronic heart failure.

AIMS: To evaluate the utility of intrathoracic impedance monitoring for detecting heart failure (HF) deterioration in patients with an implanted cardiac resynchronization/defibrillation device. METHODS AND RESULTS: Patients enrolled in the European InSync Sentry Observational Study were audibly alerted by a device algorithm if a decrease in intrathoracic impedance suggested fluid accumulation. Clinical HF status and device data were assessed at enrolment, during regular follow-up, and if patients presented with an alert or HF deterioration. Data from 373 subjects were analysed. Fifty-three alert events and a total of 53 clinical events (HF deterioration defined by worsening of HF signs and symptoms) were reported during a median of 4.2 months. Adjusted for multiple events per patient, the alert detected clinical HF deterioration with 60% sensitivity (95% CI 46-73) and with a positive predictive value of 60% (95% CI 46-73). Higher NYHA class at baseline was predictive for adequate alert events during follow-up (P < 0.05). In 11 of 20 HF deteriorations without preceding alert, an upstroke of the fluid index occurred without reaching the programmed alert threshold. CONCLUSION: A device-based algorithm that alerts patients in case of decreasing intrathoracic impedance facilitates the detection of HF deterioration. Future randomized, controlled trials are needed to test whether the tailored use of intrathoracic impedance monitoring can improve the ambulatory management of patients with chronic HF and an implanted device.

Long-term survival of patients with heart failure and ventricular conduction delay treated with cardiac resynchronization therapy.

This multicenter longitudinal observational trial was designed to analyze the long-term outcome of patients with heart failure (HF) treated with cardiac resynchronization therapy (CRT) alone or with implantable cardioverter-defibrillator (ICD) backup in a daily practice scenario. It is unknown whether the magnitude of survival benefits conferred by CRT in a daily practice scenario is comparable to what has been observed in randomized controlled trials and whether this benefit is sustained over the long term. The outcome of 1,303 consecutive patients with ischemic or nonischemic cardiomyopathy on optimal pharmacologic therapy treated from August 1, 1995 to August 1, 2004 at 4 European centers with CRT alone (44%) or with ICD backup for symptomatic HF and prolonged QRS duration was assessed. Cumulative event-free survival was evaluated for a combined end point, defined as death from any cause, urgent transplantation, or implantation of a left ventricular assist device. The cumulative incidence of competing events, HF, sudden cardiac death, and noncardiac death, was also assessed. Event-free survival was similar across the different centers. At 1 and 5 years, cumulative event-free survivals were 92% (95% confidence interval [CI] 91 to 94) and 56% (95% CI 48 to 64), respectively. The cumulative incidence of HF deaths was 25.1% (95% CI 19 to 31.7), whereas that of sudden death was 9.5% (95% CI 5.1 to 15.7). Using multivariate analysis, CRT with an ICD backup was associated with a nonsignificant decrease in mortality by 20% (hazard ratio 0.83, 95% CI 0.58 to 1.17, p = 0.284), with a highly significant protective effect against sudden cardiac death (hazard ratio 0.04, 95% CI 0.04 to 0.28, p <0.002). In conclusion, patients with advanced HF and a wide QRS complex routinely treated with CRT have a favorable long-term outcome that was reproducible at different centers. The leading cause of death in these patients remained HF, and this mode of death was competing with other causes in determining outcome. Total mortality was 20% lower with ICD backup (95% CI 42% lower to 17% higher) due to a protective effect against sudden cardiac death.

Implantation of active fixation leads in coronary veins for left ventricular stimulation: report of five cases.

BACKGROUND: Securing transvenous left ventricular (LV) pacing leads without an active fixation mechanism in proximal coronary vein (CV) segments is usually challenging and frequently impossible. We investigated how active fixation leads can be safely implanted in this location, how to avoid perforating the free wall of the CV, and how to recognize and respond to perforations. MATERIALS AND METHODS: In five patients with no alternative to LV pacing from proximal CV segments, 4 Fr SelectSecure (Medtronic, Minneapolis, MN, USA) leads, which have a fixed helix, were implanted through a modified 6 Fr guide catheter with a pre-shaped tip (Launcher, Medtronic). RESULTS: Active fixation leads were successfully implanted in proximal CVs in five patients. There were no complications. Acute and chronic pacing thresholds were comparable to those of conventional CV leads. The pre-shaped guide catheter tip remains in close proximity to the myocardial aspect of the CV, directing the lead helix toward a safe implantation site. CONCLUSIONS: If only proximal CV pacing sites are available, 4 Fr SelectSecure leads can be safely implanted through a modified Launcher guide catheter, avoiding more invasive implantation techniques. Other than venous stenting or implantation of leads with retractable tines, SelectSecure leads are expected to remain extractable.

Sleep-disordered breathing in patients with symptomatic heart failure: a contemporary study of prevalence in and characteristics of 700 patients.

AIM: Evaluation of the prevalence and nature of sleep-disordered breathing (SDB) in patients with symptomatic chronic heart failure (CHF) receiving therapy according to current guidelines. METHODS AND RESULTS: We prospectively screened 700 patients with CHF (NYHA class> or =II, LV-EF< or =40%) for SDB using cardiorespiratory polygraphy (Embletta). Furthermore, echocardiography, cardiopulmonary exercise and 6-min walk testing were performed. Medication included ACE-inhibitors and/or AT1-receptor blockers in at least 94%, diuretics in 87%, beta-blockers in 85%, digitalis in 61% and spironolactone in 62% of patients. SDB was present in 76% of patients (40% central (CSA), 36% obstructive sleep apnoea (OSA)). CSA patients were more symptomatic (NYHA class 2.9+/-0.5 vs. no SDB 2.57+/-0.5 or OSA 2.57+/-0.5; p<0.05) and had a lower LV-EF (27.4+/-6.6% vs. 29.3+/-2.6%, p<0.05) than OSA patients. Oxygen uptake (VO(2)) was lowest in CSA patients: predicted peak VO(2) 57+/-16% vs. 64+/-18% in OSA and 63+/-17% in no SDB, p<0.05. 6-min walking distances were 331+/-111 m in CSA, 373+/-108 m in OSA and 377+/-118 m in no SDB (p<0.05). CONCLUSIONS: This study confirms the high prevalence of SDB, particularly CSA in CHF patients. CSA seems to be a marker of heart failure severity.

Global and regional myocardial oxygen consumption and blood flow in severe cardiomyopathy with left bundle branch block.

OBJECTIVE: In patients with dilated cardiomyopathy (DCM), left bundle branch block (LBBB) is a common finding. The characteristic feature is an asynchronous septal wall motion and most frequently a delay of the lateral and/or posterior wall segments. With the onset of cardiac resynchronization therapy, there is a focus on the specific pathophysiology of a LBBB. However, quantitative data on regional myocardial oxygen consumption (MVO(2)) and blood flow (MBF) are missing. METHODS: We studied 31 patients with severe DCM and LBBB (ejection fraction 22.1+/-7.1%) and 14 patients with mild to moderate DCM without LBBB (ejection fraction 46.7+/-7.9%). Global and regional MVO(2) as well as MBF were determined from a dynamic (11)C-acetate positron emission tomography (PET) study. RESULTS: Global MVO(2) and MBF were lower in the DCM group with LBBB than in the control group (P<0.05). Regionally, the LBBB group revealed a higher (P<0.05) MVO(2) and MBF in the lateral wall than in the other walls. The control group did not show significant differences between the myocardial walls and demonstrated a smaller variability of the parameters. CONCLUSION: DCM patients with LBBB exhibit a more heterogeneous distribution of MVO(2) and MBF among the myocardial walls than DCM patients without LBBB. Due to the LBBB associated electromechanical alterations, the highest regional values of MVO(2) and MBF are found in the lateral wall.

Effect of cardiac resynchronization therapy on global and regional oxygen consumption and myocardial blood flow in patients with non-ischaemic and ischaemic cardiomyopathy.

AIMS: We studied the effects of cardiac resynchronization therapy (CRT) on global and regional myocardial oxygen consumption (MVO2) and myocardial blood flow (MBF) in non-ischaemic (NICM) and ischaemic dilated cardiomyopathy (ICM). METHODS AND RESULTS: Thirty-one NICM and 11 ICM patients, all of them acute responders, were investigated. MVO2 and MBF were obtained by 11C-acetate PET before and after 4 months of CRT. In NICM global MVO2 and MBF did not change during CRT, while the rate pressure product (RPP) normalized MVO2 increased (P=0.03). Before CRT regional MVO2 and MBF were highest in the lateral wall and lowest in the septum. Under therapy, MVO2 and MBF decreased in the lateral wall (P=0.045) and increased in the septum (P=0.045) resulting in a more uniform distribution. In ICM, global MVO2, MBF, and RPP did not change under CRT. Regional MVO2 and MBF showed no significant changes but a similar tendency in the lateral and septal wall to that in NICM. CONCLUSION: CRT induces changes of MVO2 and MBF on a regional level with a more uniform distribution between the myocardial walls and improved ventricular efficiency in NICM. Based on the investigated parameters, CRT appears to be more effective in NICM than in ICM.

Coronary vein balloon angioplasty for left ventricular pacemaker lead implantation.

OBJECTIVES: Retrospective analysis of five cases of coronary vein balloon angioplasty performed to allow insertion of left ventricular pacing leads. BACKGROUND: Coronary vein stenoses or an insufficient vessel caliber can preclude transvenous placement of coronary vein leads. METHODS: We compared our total patient population (n = 218), in whom we implanted coronary vein leads, to those five patients who required coronary vein angioplasty to allow lead placement. Standard over-the-wire coronary artery balloon angioplasty catheters were used to dilate the vessel to 2.5 mm (n = 3) or 3.5 mm (n = 2). RESULTS: Transvenous lead placement succeeds in >99% of patients. Four cases of target vein stenoses and one case of a vein of insufficient caliber were successfully treated by balloon angioplasty. There were no complications. CONCLUSIONS: Coronary vein angioplasty is an effective and safe technique to permit transvenous left ventricular pacing lead insertion in cases of target vein stenoses or insufficient target vein caliber.