适用于三腔心脏起搏器的冠状动脉介入技术

慢性心力衰竭是临床的常见病及疑难病,心脏再同步化治疗是治疗心力衰竭的有效方法,但是其操作难度大,风险高,尤其是左心室电极的植入尤其困难,冠状动脉介入技术,如双导丝技术,锚定技术,鞘中鞘技术在左心室电极植入中的应用,可以提高手术成功率,增加安全性,值得临床推广.     

Left ventricular inhibition during cardiac resynchronization caused by sensed left-sided ventricular premature complexes

A recently published case documented left ventricular (LV) inhibition of a Boston Scientific device by a premature complex (VPC) that was undetected by the right ventricular channel. We have observed a similar response in two patients with a BIOTRONIK cardiac resynchronization device also designed with LV sensing. A spurious response simulating that of the two true cases was also observed in a third patient with a defective LV lead which created isolated false signals. The responses of the BIOTRONIK devices were identical to that of the previously reported findings with the Boston Scientific device. The observations provide insight into the timing function of cardiac resynchronization devices designed with LV sensing.     

超声无创心肌做功技术在心脏再同步化治疗的应用

近年来,无创心肌做功逐渐发展为评价心肌收缩功能的新技术。它主要依靠二维斑点追踪超声心动图与左心室压力变化构建左室压力应变环(Pressure-Strain Loop, PVL)评估左心室心肌做功。该技术克服了斑点追踪超声心动图的局限性,对后负荷进行了量化测定,有效克服了负荷依赖性,更好地客观评价心肌的功能。对临床上诊断心血管疾病和评估心血管疾病的预后有着广泛应用和发展前景。     

Novel lead anchor technique using an active fixation quadripolar left ventricular lead in cardiac resynchronization therapy

In this report, we present a case of successful advancement of a LV lead into tortuous vessels. This was achieved by deep engagement of the coronary sinus with a cannulation catheter by applying the anchor technique using the Medtronic Attain Stability Quad lead.     

Continuously adjusting CRT therapy: clinical impact of adaptive cardiac resynchronization therapy

Cardiac resynchronization therapy (CRT) is a well-established therapy to reduce morbidity and mortality in patients with moderate and severe symptomatic congestive heart failure. Left ventricular (LV) pacing that fuses with intrinsic right ventricular (RV) conduction results in similar or even better cardiac performance compared to biventricular (Biv) pacing. Optimal programming of the atrio-ventricular (AV) and inter-ventricular (VV) delays is crucial to improve LV performance since suboptimal programming of AV and VV delays affect LV filling as well as cardiac output. CRT optimization using echocardiogram is resource-dependent and time consuming. Adaptive CRT (aCRT) algorithm provides a dynamic, automatic, ambulatory adjustment of CRT pacing configuration (Biv or LV pacing) and optimization of AV and VV delays. aCRT algorithm is safe and efficacious for CRT-indicated patients without permanent atrial fibrillation. It has been shown to improve CRT response and reduce morbidity and mortality for patients with normal AV conduction.     

Morphology of the RV electrogram during LV pacing is related to the hemodynamic effect in cardiac resynchronization therapy

Background: Biventricular (BiV) pacing and left ventricular (LV) pacing both improve LV function in patients with heart failure and LV dyssynchrony. We studied the hemodynamic effect of the atrioventricular (AV) interval and the associated changes in the right ventricular (RV) electrogram (EGM) during LV pacing and compared this with the hemodynamic effect of optimized sequential BiV pacing.
Methods: In 16 patients with New York Heart Association (NYHA) class II to IV, sinus rhythm with normal AV conduction, left bundle branch block (LBBB), QRS > 130 ms, and optimal medical therapy, the changes in RV EGM during LV pacing with varying AV intervals were studied. The hemodynamic effect associated with these changes was evaluated by invasive measurement of LVdP/dt_max and compared with the result of optimized sequential BiV pacing in the same patient.
Results: All patients showed electrocardiographic fusion during LV pacing. The morphology of the RV EGM showed changes in the RV activation that indicated a shift in the extent of fusion from LV pacing. These changes were associated with significant changes in LVdP/dt_max. Baseline LV dP/dt_max was 734 ± 177 mmHg/s, which increased to 927 ± 202 mmHg/s (P<0.0001) with optimized LV pacing and to 920 ± 209 mmHg/s (P<0.0001) with optimized sequential BiV pacing.
Conclusion: The RV EGM is a proper indicator for intrinsic activation over the right bundle during LV pacing and reveals the transition to fusion in the RV EGM that is associated with a decrease in LVdP/dt_max. The hemodynamic effect of optimized LV pacing is equal to optimized sequential BiV pacing.     

Rate-dependent aberrancy and cardiac resynchronization therapy

Left bundle branch block (LBBB) can result in significant dyssynchrony in left ventricular (LV) contraction, ultimately leading to cardiac remodeling. LBBB can be rate dependent and may appear with LV systolic dysfunction. Cardiac resynchronization therapy (CRT) has been demonstrated to improve hemodynamics as well as clinical symptoms in patients with LBBB. We describe the case of a 57-year-old man who underwent CRT implantation due to exertional dyspnea, rate-dependent LBBB, and impaired left LV systolic function.     

Double wire technique to catheterize sharply angulated coronary sinus branches in cardiac resynchronization therapy

Placing a pacing lead for left ventricular pacing through the coronary sinus can be hampered by anatomic obstacles. In this case report we describe a technique that can overcome the problem of sharply angulated coronary sinus branches by using simultaneously two guidewires in the target vessel.     

Atrial transseptal left ventricular lead implantation for cardiac resynchronization therapy using arteriovenous loop technique

To date, several techniques for transseptal left ventricular (LV) endocardial pacing for cardiac resynchronization therapy (CRT) have been proposed in patients for whom routine transvenous LV pacing is infeasible. These techniques are of varying difficulty and complexity, and some requires devices not easily accessible. We herein report a simple, safe and effective approach of atrial transseptal LV lead implantation using arteriovenous loop technique in a patient for whom transvenous LV implantation lead had failed.     

A new endocardial "over-the-wire" or stylet-driven left ventricular lead: first clinical experience

Transvenous left ventricular (LV) leads are primarily inserted "over-the-wire" (OTW). However, a stylet-driven (SD) approach may be a helpful alternative. A new polyurethane-coated, unipolar LV lead can be placed either by a stylet or a guide wire, which can be inserted into the lead body from both ends. The multicenter OVID study evaluates the clinical performance of this new steroid- and nonsteroid eluting lead. The primary endpoint is the LV lead implant success rate after identification of the coronary sinus (CS). Secondary endpoints include complication rate, short- and long-term lead characteristics, overall procedure and LV lead placement duration, total fluoroscopy time, and lead handling characteristics ratings. To date, 96 patients with heart failure (68 +/- 9 years old, 76% men) are enrolled. The CS was identified in 95 patients and, in 85 (88.5%), the LV lead was successfully implanted. The final lead positioning was lateral in 41%, posterolateral in 35%, anterolateral in 18%, and great cardiac vein in 6% of patients. In 70%, the 85 successful implantations, both stylet-driven and guide-wire techniques were used, a stylet only was used in 22%, and a guide wire only in 8%. Mean overall duration of 85 successful procedures was 112 +/- 40 minutes, total fluoroscopy time 28 +/- 15 minutes, and the duration of LV lead placement was 35 +/- 29 minutes. During a 3-month follow-up, the loss of LV capture occurred in three and phrenic nerve stimulation in six patients. The mean long-term pacing threshold is 0.8 V/0.5 ms and pacing impedance is 550 Omega. The OVID data suggest that these new leads are safe and effective. The choice of both OTW and SD techniques during lead implantation offers greater procedural flexibility.     

A New Endocardial "Over-the-Wire" or Stylet-Driven Left Ventricular Lead:

Transvenous left ventricular (LV) leads are primarily inserted "over-the-wire" (OTW). However, a stylet-driven (SD) approach may be a helpful alternative. A new polyurethane-coated, unipolar LV lead can be placed either by a stylet or a guide wire, which can be inserted into the lead body from both ends. The multicenter OVID study evaluates the clinical performance of this new steroid- and nonsteroid eluting lead. The primary endpoint is the LV lead implant success rate after identification of the coronary sinus (CS). Secondary endpoints include complication rate, short- and long-term lead characteristics, overall procedure and LV lead placement duration, total fluoroscopy time, and lead handling characteristics ratings. To date, 96 patients with heart failure (68 ± 9 years old, 76% men) are enrolled. The CS was identified in 95 patients and, in 85 (88.5%), the LV lead was successfully implanted. The final lead positioning was lateral in 41%, posterolateral in 35%, anterolateral in 18%, and great cardiac vein in 6% of patients. In 70%, the 85 successful implantations, both stylet-driven and guide-wire techniques were used, a stylet only was used in 22%, and a guide wire only in 8%. Mean overall duration of 85 successful procedures was 112 ± 40 minutes, total fluoroscopy time 28 ± 15 minutes, and the duration of LV lead placement was 35 ± 29 minutes. During a 3-month follow-up, the loss of LV capture occurred in three and phrenic nerve stimulation in six patients. The mean long-term pacing threshold is 0.8 V/0.5 ms and pacing impedance is 550 Ω. The OVID data suggest that these new leads are safe and effective. The choice of both OTW and SD techniques during lead implantation offers greater procedural flexibility.     

Termination of desynchronization rhythm and restoration of cardiac resynchronization by left‐sided ventricular premature complexes

Cardiac resynchronization devices that sense left ventricular (LV) activity and can detect interruptions of resynchronization therapy are able to record all forms of desynchronization rhythms, which are triggered by misalignment of LV timing cycles. We report five cases of this desynchronization rhythm that were terminated by isolated left‐sided ventricular premature complexes (LVPC) undetected by the right ventricular (RV) channel and unaccompanied by changes in the duration of the RV pacing cycles. In three cases, the devices did not even sense the LVPCs responsible for desynchronization termination. The restoration of resynchronization in our cases is in contrast to the traditional termination mode that is invariably associated with changes in the duration of the RV cycles.     

Pacemaker optimization in nonresponders to cardiac resynchronization therapy: left ventricular pacing as an available option

Background: Echocardiographic (ECHO)‐guided pacemaker optimization (PMO) in cardiac resynchronization therapy (CRT) nonresponders acutely improves left ventricular (LV) function. However, the chronic results of LV pacing in this group are less understood. Methods: We retrospectively studied 28 CRT nonresponders optimized based on ECHO to LV pacing and compared them to 28 age‐ and gender‐matched patients optimized to biventricular (BiV) pacing. ECHOs with tissue Doppler imaging assessed LV hemodynamics before, immediately after, and 29 ± 16 months after PMO. Also, 56 age‐ and gender‐matched CRT responders were included for comparison of clinical outcomes. Results: PMO resulted in acute improvements in longitudinal LV systolic function and several measures of dyssynchrony, with greater improvements in the LV paced group. Chronic improvements in ejection fraction (EF) (3.2 ± 7.7%), and left ventricle end‐systolic volume (LVESV) (?11 ± 36 mL) and one dyssynchrony measure were seen in the combined group. Chronically, both LV and BiV paced patients improved some measures of systolic function and dyssynchrony although response varied between the groups. Survival at 3.5 years was similar (P = 0.973) between the PMO (58%) and nonoptimized groups (58%) but survival free of cardiovascular hospitalization was significantly (P = 0.037) better in the nonoptimized group. Conclusions : CRT nonresponders undergoing PMO to either LV or BiV pacing have acute improvements in longitudinal systolic function and some measures of dyssynchrony. Some benefits are sustained chronically, with improvements in EF, LVESV, and dyssynchrony. A strategy of ECHO‐guided PMO results in survival for CRT nonresponders similar to that of CRT patients not referred for PMO. (PACE 2012; 35:685–694))     

Invasive optimization of cardiac resynchronization therapy: role of sequential biventricular and left ventricular pacing

BACKGROUND: Aim of this invasive study was to characterize and quantify changes in left ventricular (LV) systolic function due to sequential biventricular pacing (BV) as compared to right atrial triggered simultaneous BV (BV(0)), LV, and right ventricular (RV) pacing in patients with congestive heart failure (CHF). METHODS: In 22 CHF patients, all in sinus rhythm, temporary multisite pacing was performed prior to implantation of a permanent system. LV systolic function was evaluated invasively by the maximum rate of LV pressure increase (dP/dt(max)). Sequential BV pacing was performed with preactivation of either ventricle at 20-80 ms. RESULTS: In comparison to RV pacing, LV and BV(0) pacing increased dP/dt(max) by 33.9 +/- 19.3% and 34.0 +/- 22.6%, respectively (P < 0.001). In 9 patients, optimized sequential BV pacing further improved dP/dt(max) by 8.5 +/- 4.8% compared to BV(0) (range 3.3-17.1, P < 0.05). In 10 patients exhibiting a PR interval < or =200 ms, LV pacing was either superior (n = 6) or equal to BV(0) pacing (n = 4). In these 10 patients, LV pacing yielded a 7.4 +/- 8.0% higher dP/dt(max) than BV(0) pacing (P < 0.05). CONCLUSIONS: Using sequential BV pacing, generally with LV preactivation, moderate improvements in LV systolic function can be achieved in selected patients. Baseline PR interval may aid in the selection of the optimum cardiac resynchronization therapy (CRT) mode, favoring LV pacing in patients with a PR interval < or =200 ms.     

Cardiac resynchronization after left ventricular lead extraction: usefulness of angioplasty in coronary sinus stenosis

A 68-year-old man, 54 months after having been implanted with a biventricular device, underwent successful extraction of the malfunctioning left ventricular (LV) lead using mechanical dilation. During LV lead reimplantation, venography documented stenosis of the coronary sinus (CS). To overcome the obstacle, balloon angioplasty was performed and a LV lead was then inserted into a lateral tributary of the CS. The procedure was complicated by local infection and, after 2 months, removal of the entire unit became necessary. During controlateral device implantation, a second angioplasty was carried before insertion of the new LV lead because, in the meantime, restenosis had developed in the CS.     

Electrical remodeling and cardiac dimensions in patients treated by cardiac resynchronization and heart failure controls

BACKGROUND: Cardiac resynchronization therapy (CRT) reduces the left ventricular diameter (LVEDD) in heart failure (HF) patients with left bundle branch block (LBBB). The study compares structural and electrical remodeling in HF patients on CRT and matched HF controls without LBBB. METHODS: In 42 patients (64 +/- 9 years left ventricular ejection fraction [LVEF] 25 +/- 8%, 16 coronary artery disease, 26 nonischemic cardiomyopathy, 21 with LBBB and CRT indication vs 21 controls [matched for gender, age, LVEF, and underlying disease]) an unpaced electrocardiogram (ECG) and echocardiogram were recorded at baseline (bl) and after 20.6 +/- 13.8 months (fup). LVEDD, left atrial (LA) width, mitral regurgitation (MR), P-wave, PR interval, QRS width, QRS vector, and QT interval were analyzed. RESULTS: LVEDD diminished with CRT (bl 68.7 +/- 10.3 vs fup 62.0 +/- 7.7 mm, P = 0.002). Controls showed no change (bl 64.1 +/- 9.4 vs fup 64.8 +/- 8.4 mm, P = n.s.). MR improved with CRT (bl 1.2 +/- 0.6 vs fup 0.8 +/- 0.7, P = 0.02), but not among controls. LA width tended to decrease on CRT (CRT bl 48.9 +/- 4.4 vs fup 46.9 +/- 7.2 mm, P = 0.17, controls bl 48.5 +/- 5.1 vs fup 47.5 +/- 6.5 mm, P = 0.49). PR interval lengthened in both groups (CRT bl 175 +/- 29 vs fup 188 +/- 30 ms, P = 0.03, controls bl 177+/-25 vs fup 187 +/- 19 ms, P = 0.27). QRS increased in both groups (CRT bl 165 +/- 22 vs fup 171 +/- 20 ms, P = 0.07, controls bl 111 +/- 17 vs fup 118 +/- 19 ms, P = 0.01). Analyses revealed no significant association of echocardiographic and ECG parameters. CONCLUSIONS: Despite LVEDD reduction with CRT, electrical activation does not recover. Electrical remodeling does not differ between LBBB patients under CRT and matched controls without CRT indication.     

Usefulness of a Pacing Guidewire to Facilitate Left Ventricular Lead Implantation in Cardiac Resynchronization Therapy

Background: Intraoperative measurements of left ventricular (LV) pacing and sensing values were assessed using a novel 0.014-inch guidewire (Visionwire^®, Biotronik GmbH, Berlin, Germany) enabling pacing and sensing at the distal tip before final LV lead implantation .
Methods: Twenty-two consecutive patients selected for cardiac resynchronization therapy were studied .
Results: Significant correlation was found between the LV pacing threshold as assessed by the Visionwire^® and values after final LV lead implantation (r = 0.92, P < 0.001). Correlation for LV sensing was also significant (r = 0.72, P < 0.001). No significant correlation was present with respect to phrenic nerve stimulation. However, no phrenic nerve stimulation at 10 V/0.5 ms using the Visionwire^® identified 88% of patients without phrenic nerve stimulation at 10 V/0.5 ms with subsequent LV lead measurements .
Conclusion: This technique may facilitate transvenous LV lead implantation by preventing implantation in a unsuitable target vessel with respect to pacing and sensing values or phrenic nerve stimulation, thereby reducing procedure and fluoroscopy time .